SCIENCE BRINGS NATIONS TOGETHER The XXIII International Scientific Conference of Young Scientists and Specialists (AYSS-2019)

15 Apr 2019, 09:00 → 19 Apr 2019, 16:00 Europe/Moscow

LIT, JINR

The XXIII International Scientific Conference of Young Scientists and Specialists (AYSS-2019) will be held on 15 - 19 April 2019 at the Laboratory of Information Technologies, Joint Institute for Nuclear Research (JINR, Dubna, Russia). The Conference is held annually and attended by students, young scientists and specialists from scientific centers over the world. The selected talks will be recommended to publish in the refereed journal. Participation in the Conference will be confirmed by a certificate. 

This year we celebrate the International Year of the Periodic Table. The year 2019 marks the 150th anniversary of the development of the Periodic Law of the Elements by Dmitri Mendeleev. 

 

TOPICS 

Within the framework of the Conference leading scientists will give lectures on the recent theoretical, experimental and applied investigations conducted all around the world with emphasis on the major results obtained at JINR. All participants are encouraged to submit abstracts on the following topics: 

• Theoretical Physics
• Mathematical Modeling and Computational Physics
• High Energy Physics
• Particle Accelerators and Nuclear Reactors
• Experimental Nuclear Physics
• Information Technology
• Condensed Matter and Applied Physics 
• Life Science

"Deep and Machine Learning methods for document clustering and classification" tutorial will be held by Dr. Alexei I. Streltsov (Senior Data Scientist, SAP SE, Germany) and HybriLIT heterogeneous computation team on Wednesday. All details, including the registration form, can be found at https://indico-hlit.jinr.ru/event/146/

PARTICIPANTS

Students, young scientists and specialists under 35 years from all over the world are invited to participate in the Conference with oral or/and poster presentations. The registration will be open until March 1, 2019. Right after the registration you will receive a confirmation about your participation from the Organizing Committee. The abstracts of presentations will be accepted until March 1, 2019.

 

SCIENTIFIC ADVISORY BOARD:	ORGANIZING COMMITTEE:
Chairman: Grigory Shirkov (JINR)	Co-chairman: Aidos Issadykov
Nikolay Arsenyev (BLTP JINR)	Co-chairman: Alexander Verkheev
Vladimir Chausov (LRB JINR)	Alexey Aparin
Olga Derenovskaya (LIT JINR)	Anton Dolzhikov
Otilia Culicov (FLNP JINR)	Svetlana Gertsenberger
Alexander Karpov (FLNR JINR)	Constantin Hramco
Dmitry Peshekhonov (VLHEP JINR)	Inna Kolesnikova
Dmitry Podgainy (LIT JINR)	Olga Korotchik
Oleg Smirnov (DLNP JINR)	Dmitry Pugachev
	Anna Rybakova
	Andrey Shemchuk

THE WORKING LANGUAGE of the Conference is English.

REGISTRATION FEE is 5000 RUB.
Registration fee covers organizing expenses, coffee breaks and social programme.

SECTIONS

During the conference, the participants will present their reports in eight topical sections.

Circulars 1stCircular.pdf 2ndCircular.pdf

Poster Poster

Monday 15 April

Registration: Guests

What should be description?

Registration: JINR staff

What should be description?

Opening

Plenary session: Prof. Sharkov Boris "JINR – a world center for fundamental physics"

Convener: Dr Olga Derenovskaya (LIT JINR)

Plenary session: Dr. Karpov Alexander "Superheavy Element Factory"

Convener: Dr Olga Derenovskaya (LIT JINR)

12:00 Coffee break

Plenary session: Dr. Lavrik Evgeny "Compressed Baryonic Matter experiment at FAIR"

Convener: Dr Olga Derenovskaya (LIT JINR)

13:30 Lunch

Mathematical Modeling and Computational Physics: Part 1

Conveners: Dr Alexander Gusev (Laboratory of Information Technologies Joint Institute for Nuclear Research), Dr Olga Derenovskaya (LIT JINR)

1 Numerical modeling of superconductors and their application for magnetic shielding

Electron cooling system for the NICA project requires a high homogeneity of the magnetic field in order to obtain the required cooling efficiency. High temperature superconducting open-type shielding could decrease the costs of such system (compared to the conventional high precision solenoid windings). Shielding effect of HTS tape was tested. The experiments were conducted in JINR, Russia, in the magnetic fields up to 40 mT. Numerical model of the shield was created and compared with the results obtained from experiments.

Speaker: Mr Błażej Skiba (Wrocław University of Science and Technology)

2 A “vector finder” approach to track reconstruction in the Inner Tracking System of MPD/NICA.

At present, the accelerator complex NICA [1] is being built at JINR (Dubna). It is intended for performing experiments to study interactions of relativistic nuclei and polarized particles (protons and deuterons). One of the experimental facilities MPD (MultiPurpose Detector) [2] was designed to investigate nucleus-nucleus, proton-nucleus and proton-proton interactions. As one of the possible MPD upgrade steps, an Inner Tracking System (ITS) based on the next generation silicon pixel detectors [3] is being considered to be installed between the beam pipe and the Time Projection Chamber (TPC). It is expected that such a detector will increase the research potential of the experiment for both the proton-proton (high luminosity) and nucleus-nucleus (high particle multiplicity) interactions. According to the proposed design, the MPD ITS will consist of five layers of silicon pixel detectors. The main purpose of the ITS is to provide a better precision of the primary and secondary vertex reconstruction and improve track reconstruction in the MPD in the region close to the interaction point. The existing in the MPD track reconstruction method is based on the Kalman filter in the TPC. Its simple extension to the ITS is not adequate to fully exploit the potential of the new detector, therefore such a method cannot be considered as a good tool to study ITS performance. That is why another algorithm, based on the “vector finder” approach, was developed. This paper describes the proposed track finding algorithm for the ITS of MPD and presents its performance results obtained on Monte-Carlo generated data of nucleus-nucleus collisions. [1] Nuclotron-based Ion Collider fAcility web-site: http://nica.jinr.ru [2] MultiPurpose Detector web-site: http://mpd.jinr.ru [3] B.Abelev et al [ALICE Collaboration], J. Phys., G41 (2014) 087002

Speaker: Mr Dmitry Zinchenko (JINR)

Slides AYSS_Zinchenko.pdf AYSS_Zinchenko.pptx

3 Monte Carlo study of the systematic errors in the measurement of 15N ions scattering from 10,11B.

A series of experiments on the elastic scattering of 15N ions from 10,11B has been done at U-200P cyclotron at Heavy Ion Laboratory, Warsaw University using the charged particles detection system ICARE. The measured differential distributions are used for obtaining the theoretical interpretation in terms of the Optical Model for pure elastic scattering and Distorted wave Born Approximation for the cluster transfer mechanism. The reliability of the interpretation depends on the systematic errors of the experiment. In this work, we report on a Monte Carlo study of such errors using the ExpertRoot simulation and analysis framework based on the FairRoot package. Influence of such factors as angular, spatial and energy spread of the beam, energy loss and multiple scattering in the target and the dimension of the detector slit on the angular resolution of the detector and the reconstructed differential cross section are investigated. The Monte Carlo model allowed to study the influence of the ion identification and detection efficiency and the energy resolution as well. However, in the given experiment these factors were not of any importance. As a result, it has been demonstrated that the reconstructed differential cross section is slightly different from the input one. The main reason for this distinction is the beam spot size at the target. Influence of the slit length is negligible, hence it can be increased for better detection efficiency. The developed software will be used for planning and analyzing similar experiments in the future.

Speaker: Mr Ilyas Satyshev (JINR)

4 Analysis of Passive Heat Removal System by ANSYS FLUENT software

In the current study, the model of Passive Heat Removal System (PHRS) through SG (steam-generator) was developed for computational fluid dynamics (CFD) analysis. Passive Heat Removal System is a protective safety system of Nuclear Power Plant based on the principle of a passive action, designed to provide long-term heat removal from the reactor core via secondary circuit. A thorough description of the steam condensation process in the passive cooling system obtained as a result of the analysis. The rate of the steam condensation in heat exchanger pipeline was assessed and compared with previous results calculated by "ANSYS CFX" software.

Speaker: Mr Taron Petrosyan (Brno University of Technology)

5 Realistic simulation of the MPD Time Projection Chamber with Garfield.

The detailed simulation of electron drifting in the MPD TPC was made with CERN Garfield toolkit for the simulation of gas particle detectors. For electron transporting were used the Ar+CH4 gas mixture with impact of magnetic and electric fields. Ionization processes were investigated in the wire planes area near readout chambers of the TPC.

Speaker: Mr Alexander Bychkov (JINR)

6 High performance simulation of the magnetization reversal phenomenon in the ϕ0 Josephson junction

The φ0-Josephson junction model with direct coupling between magnetic moment and Josephson current is considered. In this framework, effect of the full magnetization reversal is numerically studied in the wide range of parameters of the model. The simulation is based on the implicit two-stage Gauss-Legendre algorithm of the 4th accuracy order. Effect of parallel execution of respective C++ computer code is demonstrated. Calculations have been carried out at the Heterogenius Platform “HybriLIT”.

Speaker: Mr Maxim Bashashin (JINR)

Slides Bashashin_AYSS-2019.pdf

Particle accelerators and nuclear reactors: Part 1

Conveners: Mr Mikhail Nozdrin (LHEP), Mr Mikhail Shandov (Joint Institute for Nuclear Research, Veksler and Baldin Laboratory of High Energy Physics)

7 CRYOGENIC TARGETS OF THE LIGHTEST GASES (HYDROGEN, DEUTERIUM AND HELIUM-4) WITH GM CRYOCOOLER FOR EXPERIMENTS OF HIGH ENERGY PHYSICS

Researches of collision processes of elementary nuclei on the extracted beams of the NICA accelerator complex by the BM@N physics installation need cryogenic targets with unique ratios between the amounts of working substance (liquid hydrogen, deuterium or helium) and the mass of the target's housing, which may have the interaction with an ion beam, result the secondary particles, and initiate the background events. The first part of the article describe the well-known method of cooling the cryogenic targets with polymeric housing by liquid helium and experimental data on the permeability and strength of various materials at low temperatures, as well as starting and operating parameters are given. The installations created according to this method and based on such targets have proven themselves well when working in many accelerator sessions. An exceptional feature of these installations is the double helium heat exchange condenser. In the second part of the article an updated method of cryogenic targets cooling by using the GM cryocooler is given. A maximum cooling capacity of GM cryocooler is 1.5 watts at 4.2 Kelvin, which looks acceptable for such application. The using of GM cryocooler allows creating a fully autonomous and mobile cryogenic target, which not depends from outside cold source. Authors put attention on a serious problem of heat leakage, including heat gain from radiation at a maximum beam intensity of 10 ^ 11 particles / s, and propose using cryocooler's refrigeration power to prevent it. Also, in article the influence of magnetic field with intensity up to 1 Tesla on the operation of the cryocooler is discussed.

Speaker: Mr Дмитрий Климанский (НИКО, ЛФВЭ, ОИЯИ)

8 Dilution cryostats for experiments with the frozen spin polarized target at particle accelerators

The description of design and recent results of the horizontal cryostat for new Bonn frozen spin polarized target developing for the spin physics experiments with tagged photons from Bonn electron accelerator “ELSA” are given. In addition, overview of frozen spin polarized targets cooled by ³He/⁴He dilution refrigerators developed at the DLNP JINR since 1976 for different accelerators is given.

Speaker: Mr Anton Dolzhikov (JINR)

9 Tracking Simulation of the Bunched Beam Stochastic Cooling

Mapping equation for the bunched beam stochastic cooling is formulated. For the NICA project parameters the obtained result is compared with theoretical description. According to the results the preferrable stochastic cooling method for the NICA collider is clarified.

Speaker: Ivan Gorelyshev (VBLHEP JINR)

10 Particle dynamics in an accelerator with a longitudinal magnetic field.

The goal to research is to analyse of the influence of magnetic field perturbations on the dynamics of charged particles in a storage ring with a longitudinal magnetic field LEPTA. The Low Energy Particle Toroidal Accumulator, created in the VP Dzhelepov Laboratory of Nuclear Problems, JINR (Dubna) is designed for generating a directed orthopositronium flux, which is formed as a result of recombination of positrons circulating in the LEPTA ring with a single-turn electron beam of the electron cooling system of the LEPTA. To provide a long-term stability of the circulating positrons a helix quadrupole magnetic field is formed in one of the straight sections of the ring. The report presents an optical transformation matrix for the LEPTA ring, obtained on the basis of the solution of the motion equation in WKB-approximation. The experimentally measured magnetic field contains the perturbation regions and the adiabatic decay regions of the magnetic field of the helix quadrupole. Accordance with the results of measurements, a matrix including these regions is constructed and contained in Full Transformation Matrix (FTM) of the LEPTA ring. The code is built in Wolfram for this matrix made it possible to study the multi-rotational stability of particle motion in the LEPTA ring. The results are presented in the report.

Speaker: Sergey Melnikov (JINR)

11 Modeling and analysis nica accelerator complex superconducting magnets magnetic fields

NICA collider magetic system consist of dipole, quadropole and corrector twin-aperture SC magnets, IN this report design of corrector magnet is presented.

Speaker: Mr Nikita Khromov (JINR)

12 Replacing the lead coolant with Pb-Mg eutectic and the effect of these substitutions on the neutron-physical, thermophysical characteristics of fast reactors

The technical characteristics and safety conditions of the fast reactor are limited by the properties of the metal-free coolant. The lead coolant is chemically neutral, melts and boils easily at high temperatures, but the corrosiveness of lead requires great technological effort. The cause of corrosion activity is the charge polarity of lead, lead is electronegative and is a strong oxidizing agent. If you combine opposites in a eutectic alloy, you can get a compositionally stable liquid metal coolant. Magnesium is an attractive lead modifying agent. Lead - magnesium with a melting point of 248 C, lowers the oxidation potential of the alloy. Comparison of the two coolants were made by neutron and thermal characteristics.

Speaker: Mr Almas Yskakov (Frank Laboratory of Neutron Physics)

Theoretical Physics: Section 1 Part 1

Conveners: Dr Andrey Pikelner (BLTP JINR), Dr Vsevolod Katkov (BLTP JINR), Yaroslav Klopot (BLTP JINR)

13 Variational calculations of the H^+_2 and HD^+ rovibrational energies

We use the exponential explicitly correlated variational basis set of the type exp(−α_n*R−β_n*r_1−γ_n*r_2) to calculate systematically the nonrelativistic bound-state energies for the hydrogen molecular ion H^+_2 and HD^+.We perform calculations for the states of the total orbital angular momentum L=0-4 with the complete set of vibrational quantum numbers v=0–10.

Speaker: Mr Askhat Bekbaev (JINR)

14 Short-range-Induced Resonances in Two-dimensional Dipolar Scattering

We investigate the two-dimensional dipole-dipole scattering problem at low energies, which simulates the polar molecules collisions in the optical traps. The resonances induced by short-range interactions are revealed in the scattering cross section dependence on the short-range interaction radius.

Speaker: Mr Eugene Koval (BLTP, JINR)

15 Tunneling of two interacting atoms from excited states

We consider a tunneling problem of two interacting cold atoms, with the even spatial symmetry, subject to an anharmonic optical trap and linear magnetic-field gradient. The atoms are initially prepared in the two lowest excited states with respect to relative and center-of-mass motions. We calculate the energy spectrum for a wide range of the interatomic coupling strength g. In the limit of zero coupling, an avoided crossing of the energy levels is revealed. We observe monotonic and non-monotonic dependence of a tunneling rate as a function of g. We find a condition to observe a transition from uncorrelated to correlated pair tunneling as a function of g and a size of the external trap barrier. This system, although for lower energy levels, has been recently investigated in the deterministic Heidelberg experiment using two interacting lithium-6 atoms.

Speaker: Mr Ilyas Ishmukhamedov (Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research)

16 Resonance features of the Josephson junction with ferroelectrical barrier

The phase dynamics of Josephson junction with ferroelectric barrier is investigated. The Josephson junction dynamics is described in the framework of RCSJ-model and for description of the ferroelectricity is used Landau-Devonshir theory. The IV-characteristic of Josephson junction with ferroelectric barrier is calculated. Its shown that, due to the resonance between Josephson and polarization oscillations in ferroelectric layer is observed increasing of the polarization amplitude and on IV-curve appears resonance branch.

Speaker: Dr Ilhom Rahmonov (BLTP, Joint Institute for Nuclear Research)

17 How to assemble polydisperse nanoparticles into clusters with predefined fractal dimension?

A generalized non-kinetic off-lattice algorithm to construct stochastic fractal clusters of polydisperse particles with tunable cluster parameters including dimension, is presented. The model is based on a hierarchical procedure and makes it possible to cover the full range of natural mass fractal dimensions between one and three. A morphological study of numerically generated clusters based on the correlation analysis in both direct and reciprocal spaces is given regarding small-angle scattering analysis.

Speaker: Mr Oleksandr Tomchuk (Physics Department, National Taras Shevchenko University of Kyiv)

18 Influence of stationary charge imbalance on Shapiro step features

The nonequilibrium phenomena in the coupled system of Josephson junctions, taking into account the charge imbalance of the elementary excitations spectrum branches has been studied. We investigate the influence of stationary charge imbalance on the Shapiro step properties on the current-voltage characteristics of coupled system of Josephson junctions. It has been found that Shapiro step demonstrates a shift and a slope with respect to its original position, determined by V=Nω. The value of the slope increases with increasing in nonequilibrium parameter. The shift appears due to nonperiodic boundary conditions and its value increase under the influence of stationary charge imbalance in the system. Obtained results are in good agreement with a results published in ref.[1,2,3]. Acknowledgments This work is supported by RFBR grant № 18-32-00950. [1] Yu. M. Shukrinov, M. Nashaat, K. V. Kulikov, R. Dawood, H. El Samman and Th. M. El Sherbini, EPL, 115, 20003 (2016) [2] Kirill Kulikov, Yury Shukrinov, Majed Nashaat, and Akinobu Irie, EPJ Web of Conferences, 173, 03015 (2018) [3] D. A. Ryndyk, J. Keller and C. Helm., J. Phys.: Condens. Matter, 14, 815 (2002)

Speaker: Mr Kirill Kulikov (RF)

16:30 Coffee break

Mathematical Modeling and Computational Physics: Part 2

Conveners: Dr Alexander Gusev (Laboratory of Information Technologies Joint Institute for Nuclear Research), Dr Olga Derenovskaya (LIT JINR)

19 Solving the Optimization Problem for Designing a Pulsed Cryogenic Cell

The paper considers the problem of optimiziation of the heat source characteristics of the cryogenic cell -- a multi-layer cylindrical configuration of the sandwich type, intended for pulse dosed injection of the working gaseous spicies in to the ionization chamber of the multiply charged ion source. For solving the optimization problem, a hybrid MPI+OpenMP parallel computation algorithm based on the brute force method for finding the maximum of the proportional integral of the volume of the gas evaporated from the surface of the cell has been developed and implemented. The solving of the optimisation problem for the particular configuration of cells using the cluster "Govorun" has demonstrated the acceleration of calculations in the tens and hundreds of times.

Speaker: Mr Alexander Ayriyan (Laboratory of Information Technologies, JINR)

20 Numerical analysis of the particle scattering at finite temperature

t.b.d.

Speaker: Elizaveta Rogozhina (Student)

21 Reactor like TGE model

Terrestrial gamma flash (TGF) and thunderstorm ground enhancements(TGE) phenomena are crucial for understanding of atmosphere breakdown and lightning generation physics. The initial theory was developed by Gurevich and included only runway breakdown description. It was later updated by Babich and Dwayer, but even updated model uses a rather simplified field structure and does not fully match observed quantities. The reactor like TGE (RL-TGE) model presented in this work assumes more complicated stochastic field structure and takes into account not only one cell runway breakdown, but the whole global cell structure in the thundercloud. It allows to describe a wide variety of TGF-like events and potentially fills the gap in thundercloud parameters previously unaccounted by other theories.

Speaker: Mr Mikhail Zelenyi (INR RAS, MIPT)

Particle accelerators and nuclear reactors: Part 2

Conveners: Mr Mikhail Nozdrin (LHEP), Mr Mikhail Shandov (Joint Institute for Nuclear Research, Veksler and Baldin Laboratory of High Energy Physics)

22 The new Light-ion Linac for the NICA Collider

Upgrade of NICA injection complex requires the replacement of obsolescent LU-20 DTL linac for the new ion linear accelerator. The R&D plan includes the development of 7 AMeV-linac with future extension by additional normal-conductive RF cavities with output energy up to 13 AMeV and SC cavities up to 30-50 AMeV. The linac will provide a beam of polarised protons and light ions with a mass to charge ratio up to 3. An overview of the Linac is presented in this paper.

Speaker: Mr Andrei Martynov (JINR)

23 NICA booster control system: thermometry

NICA is a new accelerator complex being constructed on the JINR aimed to provide collider experiments with heavy ions. It consists of Electron String Ion Source, 6.2 Mev/u linac, 600 Mev/u booster synchrotron, upgraded Nuclotron and ion collider. The superconducting booster synchrotron is being assembled presently. The report describes a system, developed in JINR, to perform precise temperature measurement of NICA booster superconducting magnets. Thermometry system consists of more than 200 resistive TVO temperature sensors, National Instruments PXIe controllers and data acquisition modules, TangoControls-based software and web-based client application.

Speaker: Mr Georgy Sedykh (JINR)

24 The beam transfer lines for electronics and radiobiology applications of the NICA project.

There are several new studies in applied fields are going to be provided in the framework of the NICA project in the nearest future. These studies are linked to radiobiology and electronics applications. For these aims, three new experimental stations are going to be built. Special cosmic-likened properties of the beams are required. They can be provided by HILAC, Booster and Nuclotron technical facilities and new beam lines integrated into existed NICA channels, which are under development now. The presented results involve floor plan design, beam dynamics modelling, preliminary layout of diagnostic systems and calculations of key parameters of magnetic elements including some suggested technical solutions, which satisfy experimental requirements.

Speaker: Mr Georgy Filatov (JINR)

25 Development of beam diagnostic systems for applied research stations at VBLHEP JINR

Within the framework of NICA project an Innovation block based on three applied research stations is being constructed. The first station includes the research and testing of perspective products of semiconductor microcircuits with package for radiation resistance of heavy charged particles such as ions up to the Au with the energy range of 150-500 MeV/nucleon covering LET range 30-60 MeV/(mg/cm2). The second station is associated with research and modeling of the effects of heavy charged particles on biological objects. The ions up to the Au with energy range of 400-800 MeV/nucleon with an absorbed dose of 1 Gy will be available for experiments. For irradiation testing of decapsulated microcircuits with energy of ions up to 3.2 MeV/nucleon, accelerated in HILAC, a short-range ion irradiation station is being constructed. The specificity of this station associated with the low energy ions which cannot pass through the microcircuit package; therefore the package is decapsulated before irradiation. Diagnostic systems of ion beams in the research stations mentioned above are being designed to measure such beam characteristics as ion flux density, intensity, fluence, beam profile.

Speaker: Mr Alexey Slivin (JINR)

26 Optimization of the operating mode of the NICA collider for experiments at SPD: studying the effect of impedance on the dynamics of an intense proton beam

The studies of the nucleon spin structure in the collisions of polarized proton beams is the first priority task for the scientific program of The Spin Physics Detector (SPD) project at the NICA facility. Effective carrying out of these studies is possible with the luminosity of p-p collisions = 1*(10)^32 (сm)^(-2) с^(-1) at the energy E_cm = 27 GeV. This is possible with the accumulation of the ~ 2*(10)^13 particles in each of the rings of the collider NICA. In the report the condition for the implementation of a such regime and the effect of impedance on the total allowed incoherent betatron tune shift are described. The main part of the report gives examples of the calculation of the impedance for the elements which are parts of the arch of the collider NICA. The problem of calculating the effective impedance of the structure and its influence on the betatron beam motion, which is important for obtaining the largest luminosity of the collider, are considered.

Speaker: Mrs Margarita Korobitsina (JINR)

27 HILAC-Booster transport channel: beam diagnostics and the magnetic elements power supply

The new LHEP JINR linear accelerator HILAC is the main element of the NICA heavy ion injector. The HILAC-Booster beam transport channel contains dipole magnets, quadrupole lenses, a debuncher, a set of steerers and beam diagnostics elements. The magnetic elements power supply, the beam profile measurement system and its software are described.

Speaker: Mr Dmitriy Ponkin (JINR)

Theoretical Physics: Section 1 Part 2

Conveners: Dr Andrey Pikelner (BLTP JINR), Dr Vsevolod Katkov (BLTP JINR), Yaroslav Klopot (BLTP JINR)

28 CPT study of the Fermi-surface reconstruction in the t-J model

A number of recent experiments have highlighted a remarkable transformation of a large cuprate Fermi surface into small pockets in the underdoped region signaling a breakdown of a conventional Fermi liquid theory in the PG phase. The qualitatively agreement of the experimental data with Fermi surface calculations within phenomenological models based on the measured parameters of the CDW order, suggests that this reconstruction is caused by the bidirectional charge ordering. To address this problem, we employ the cluster perturbation theory based on the exact diagonalization of small clusters for the low doped t-J model. In this way, we show that the translation symmetry breaking and explicitly accounting of the short range correlations induce the FS reconstruction into a nodal electron pocket accompanied by two hole pockets as predicted by mean field calculation and in agreement with experimental data. In contrast to the phenomenological models this approach does not require the introducing of the CDW modulation term by hand and allows to obtain the FS reconstruction based on strongly electron correlations.

Speaker: Mr Ilya Ivantsov (BLTP JINR.)

29 CORRECT USAGE OF THE VLASOV EQUATION

This work is devoted to the study of the properties of the Vlasov equation, as well as the study of the limits of its applicability in the description of physical phenomena. In this paper were shown, that the well-known Vlasov equation [1], widely used in the scientific literature, is only an approximation obtained from the original chain of Vlaosv equations by introducing assumptions [2]. A generalized Vlasov equation is proposed, which is obtained from first principles without introducing any approximations [3]. The paper considers various types of dissipative systems: a classical harmonic oscillator and a relativistic harmonic oscillator with the presence and absence of dissipative forces. The system of gravitationally interacting particles in the relativistic and classical cases is also considered. The evolution of systems was described by the Vlasov equation by the particle method. It was shown that in the presence of dissipations in the system, as well as in the case of relativistic motion, the classical Vlasov equation becomes inapplicable for the description of such systems, and it is necessary to use the proposed generalized Vlasov equation. In conclusion, the results are discussed. 1. Vlasov A.A., Many-Particle Theory and Its Application to Plasma, New York, Gordon and Breach, 1961, ISBN 0-677-20330-6; ISBN 978-0-677-20330-0 2. Perepelkin E. E., Sadovnikov B. I., Inozemtseva N. G. The new modified Vlasov equation for the systems with dissipative processes // Journal of Statistical Mechanics: Theory and Experi-ment. — 2017. — Vol. 2017, no. 053207. — P. 1–22. 3. Perepelkin E. E., Sadovnikov B. I., Inozemtseva N. G. The properties of the first equation of the Vlasov chain of equations // Journal of Statistical Mechanics: Theory and Experiment. — 2015. — no. P05019.

Speaker: Mr Denis Suchkov (Lomonosov Moscow State University)

30 Role of non-abelian anomaly in transition form factors of $\pi^{0},\eta,\eta'$, generalization for the case of any photon virtuality

In the framework of the anomaly sum rules approach, based on the dispersion representation of the axial anomaly and the global quark-hadron duality hypothesis, expressions of Transition Form Factors(TFF) for the pseudoscalar mesons are derived. The obtained solutions are taking into account the mixing between $\pi^0-\eta-\eta’$ and the gluon anomaly term. Within TFF for $\pi^0-\eta-\eta’$ estimation of the gluon anomaly contribution is performed for the cases of two real photons and one virtual. Correlations between parameters of the vector and axial channels are observed.

Speaker: Mr Sergei Khlebtsov (ITEP, Moscow)

31 Kinetic description of the electron-positron plasma created from vacuum under the action of a strong laser field

We consider a self-consistent kinetic description of a electron-positron-gamma plasma, generated from the vacuum in a focal spot of two counterpropagating laser pulses. At the moment in our model includes purely time-dependent external (laser) field, but properly takes into account the semiclassical internal (plasma) field. While nonperturbative kinetic description of electron-positron pair production from vacuum have been previously addressed, quantum radiation is included in such a model for the first time. The basis of this kinetic description provides by using the BBGKY-chain, which we truncate at second order of perturbation theory by taking into account only the annihilation and bremsstrahlung channels. The goal of this work is an extended generalization of the results [1]. [1] D.B. Blaschke, V.V. Dmitriev, G. Roepke, and S.A. Smolyansky, PRD 84, 085028 (2011).

Speaker: Mr Stanislav Pirogov (Olegovich)

32 Form factors of three-nucleon nuclei in the relativistic case

A relativistic generalization of formulas for form factors of three-nucleon nuclei was obtained.The formulas for the form factors took into account the orbital moments of the nucleons inside the nuclei from 0 to 2, that is, the S P and D states.The form factors were calculated as functions of the transmitted momentum of the scattered electron up to 2 GeV.Moreover, for form factors nucleons used the models of the dipole fit, a model of a relativistic harmonic oscillator and a vector dominance model.The solutions of the Bethe – Salpeter – Faddeev equation were used as the amplitudes of the states of the nucleus used to calculate the form factors.At the same time, the potential of the nucleon-nucleon interaction is taken in a separable form using the Yamaguchi functions for form factors of potential.

Speaker: Mr Sergey Yurev (JOINT INSTITUTE FOR NUCLEAR RESEARCH)

33 Field confinement in infrared effective QCD and thermal field dynamics

Keeping in view the dominance of non-perturbative phenomenas in low energy regime of QCD, an infrared effective dual QCD, based on topologically viable homogeneous fibre bundle approach, has been analysed for exploring the dynamics of confined fields in its dynamically broken phase which has been shown to lead an unique multi-flux tube configuration and a typical glueball spectrum intimately connected to the color confining features of QCD vacuum. In addition, due to the extreme relevance of the QCD studies under varying thermal conditions, the flux-tube picture of dual QCD has further been analysed at finite temperatures for its implications to ultra-RHIC especially for the case of flux tube annihilation and the creation of quark pairs leading to the emergence of QGP in thermalised QCD vacuum. The stability of flux tubes and the associated plasma oscillations at different hadronic scales in full infrared sector of QCD have also been investigated to demonstrate its connection with particle production in the central region in RHIC events.

Speaker: Mr Deependra Singh RAWAT (Kumaun University, Nainital, India)

Tuesday 16 April

Plenary session: Dr. Shvetsov Valery "Fundamental properties of neutrons"

Convener: Dr Aidos Issadykov (Jinr)

11:00 Coffee break

Plenary session: Prof. Rubakov Valery "The Universe before the hot Big Bang"

Convener: Dr Aidos Issadykov (Jinr)

12:30 Lunch

Condensed Matter Physics: Section 1

Conveners: Dr Ivan Bobrikov (JINR), Timur Tropin (Joint Institute for Nuclear Research)

34 Microstructure investigaion of positive electrodes of Li-ion batteries by the method of small-angle neutron scattering

Currently, lithium-ion batteries are the most commonly used chemical sources of current. When considering the evolution of modern electronic devices, there is a clear tendency towards their miniaturization and increased functionality. This leads to a significant increase in energy consumption, which, in turn, requires the creation of more efficient and compact sources (accumulators) of energy. The work is aimed at conducting systematic studies of qualitative and quantitative patterns between the microstructure of electrode coatings and their specific characteristics. Information on the microstructure at all stages of the synthesis and modification of coatings will be obtained using small-angle neutron scattering, which, thanks to the high penetrating power of this radiation, allows us to study industrial systems within nondestructive testing.

Speaker: Meir Yerdauletov (jinr)

35 DIELECTRIC AND PHYSICOCHEMICAL PROPERTIES OF INTERCALATED NONTRONITE

Nontronite belongs to phyllosilicates group. It is an example of layered clay minerals of prominent sorption properties. Layered minerals form structures consisting of tetragonal and octahedral sheets. Our team focused on the unique properties of aluminosilicates and used them for modification using solvents with a constant dipole moment. The process is called intercalation. Products of intercalation have very promising properties. Previously we proved that intercalated kaolinite[1,2] or halloysite[3] can effectively absorb electromagnetic wave. It could be used for protection against negative impact of electromagnetic pollution. Characterization of nontronite composites was made by means of dielectric spectroscopy, thermogravimetry and powder diffraction. As a result, very interesting dielectric permittivity results have been obtained over a wide frequency range. [1] K. Leluk, K. Orzechowski, K. Jerie, A. Baranowski, T. SŁonka, i J. GŁowiński, „Dielectric permittivity of kaolinite heated to high temperatures”, Journal of Physics and Chemistry of Solids, t. 71, nr 5, s. 827–831, maj 2010. [2] K. Orzechowski, T. Słonka, i J. Głowinski, „Dielectric properties of intercalated kaolinite”, Journal of Physics and Chemistry of Solids, t. 67, nr 5–6, s. 915–919, maj 2006. [3] M. Adamczyk, M. Rok, A. Wolny, i K. Orzechowski, „Dielectric properties of halloysite and halloysite-formamide intercalate”, Journal of Applied Physics, t. 115, nr 2, s. 024101, sty. 2014.

Speaker: Mr Karol Kułacz (Faculty of Chemistry, University of Wroclaw)

36 Plasmon mechanism of superconductivity

Using the estimate of the characteristic length by the Heisenberg's uncertainty principle and the WKB method, the relationship between the London penetration length and the coherence length for HTSC is obtained. The relationship between the London penetration length and the wavelength of plasma oscillations is considered, on the basis of which an expression is obtained for the velocity of a Cooper pair and the critical temperature of HTSC in the plasmon mechanism of superconductivity. The calculated values of critical temperatures were checked for compliance with the experimental data for the cuprate, organic and other superconductors, good agreement was obtained.

Speaker: Mr Anton Matasov (National Research University "Moscow Power Engineering Institute")

37 General method for optimization of neutron-energy group structure of cross section libraries for different type of reactors – first approach

Nuclear cross sections strongly depend on neutron energy (e.g. their behaviors in resonance regions). To represent some reactions of resonant nuclides accurately, more than 100,000 energy points are required. Most nuclear codes cannot handle this vast amount of data. That is why, the pointwise cross sections are averaged over energy groups to form multi-group cross sections. These group constants depending on the energy group structure and weight function can be used for specific types of problems, such as thermal reactors, fast reactors, fusion problems or shielding calculations. To improve the accuracy of neutronic calculations, it is necessary to reduce the uncertainties associated with the cross sections. There are three major factors that affect the accuracy of cross section generation. These include energy group structure, self-shielding method, and collapsing methodology. There currently exists very little information that outlines the process used for generating new cross section group structures. There also exists no readily-usable tools for optimizing these group structures. This work has focused on optimizing the group structure of a fine-group libraries (~1000 groups) to a group structure suitable for fast, yet accurate deterministic transport calculations using SCALE code system. This is the first approach to finding a universal method for optimization of neutron-energy group structure of multi-group cross section libraries for any type of nuclear reactor.

Speaker: Mr Lukasz Koszuk (Faculty of Physics, University of Warsaw)

38 Determination of the impurity composition of the B-N-Al-Ti compound materials obtained under the action of high pressures and temperatures

Composite materials based on cubic boron nitride in titanium and aluminum containing systems are promising for use in the manufacturing industry to process the cutting part of the tools. In addition, due to a combination of unique characteristics, composition materials based on dense modifications of boron nitride are widely used as various functional environments of modern micro-, nanoelectronics. Samples of composite materials were synthesized at the SSPA “Scientific-Practical Materials Research Centre of NAS of Belarus” from components AlN, Al, BN and TiN at a pressure of 5 GPa and at different temperatures from 500 C up to 2000 ˚C in tungsten and cobalt carbides high-pressure chambers of the “anvil with a hole” type in containers made of lithographic stone. The duration of the synthesis for all samples was 3 minutes. 69 samples were subjected to neutron activation analysis. Due to the fact that the amount of material provided to the NAA was limited, irradiation was carried out in few stages. The concentrations of 43 elements were determined (Na, Mg, Al, Si, Cl, S, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Rb, Sr, Zr, Mo, Sn, Sb, I, Cs, Ba, La, Ce, Nd, Sm, Eu, Tb, Dy, Yb, Hf, Ta, W, Au, Th, U). The analysis allowed to determine the impurities in the raw materials and synthesized samples.

Speaker: Ms Yulia Aleksiayenak (JINR)

Life Science

Conveners: Dr Inga Zinicovscaia (Joint Institute for Nuclear Research), Mr Vladimir Chausov (LRB JINR)

39 ATMOSPHERIC RELEASES OF TRACE ELEMENTS IN CENTRAL KAZAKHSTAN BY MEANS OF MOSS-BIOMONITORS AND NEUTRON ACTIVATIVE ANALYSIS

A.S. Kabylova1, N.M. Omarov1, L.P. Strelkova2, K.N. Vergel2, M.V. Frontasyeva2 1Eurasian National University. L.N. Gumilyov, Astana, Republic of Kazakhstan 2Joint Institute for Nuclear Research, Dubna, Russian Federation Since the end of the 1970s, Western Europe used a common method proposed by Scandinavian scientists, the moss biomonitor method using moss species common in countries of temperate climate (UNECE ICP Vegetation: https://icpvegetation.ceh.ac.uk/) to study atmospheric deposition of heavy metals and other toxic elements. Mosses are analogous to aerosol filters and are living systems, the elemental composition of which reflects the state of the atmosphere. From the point of view of their prevalence, availability and ease of sampling, they are universal objects for research. For many years, the Laboratory of Neutron Physics of the Joint Institute for Nuclear Research (FLNP JINR) has been working on the study of air pollution by heavy metals using neutron activation analysis (Frontasyeva et al., 2016). Since 2014 Kazazstan has been participating in this program of the UN Commission on the Long-Range Transboundary Transport of Air Pollution in Europe (UNECE LRTAP) using the moss-biomonitor method. Previously, results were obtained for Eastern and Western Kazakhstan (Nurgalieva et al., 2018). This paper presents preliminary results of elemental analysis of (Na, Mg, Al, Cl, K, Ca, Ti, V, Br, Sr, I) based on short-lived isotopes of 39 moss samples collected in early October 2018 in Central Kazakhstan (Karkaraly region of Karaganda region). A full analysis of samples at the IBR-2 reactor of the FLNP JINR will be completed shortly. This study serves the grounds for the master's thesis of the first author of the Abstract. References • Frontasyeva M.V., Steinnes E., Harmens H. Monitoring long-term and large-scale deposition of air pollutants based on moss analysis. Chapter in a book “Biomonitoring of Air Pollution Using Mosses and Lichens: Passive and Active Approach ‒ State of the Art and Perspectives”, Edts. M. Aničić Urošević, G. Vuković, M. Tomašević, Nova Science Publishers, New-York, USA, 2016. • Nurgalieva D.Zh., Nurkassimova M.U., Omarova N.M., Dalelova A.M., Frontasyeva M.V., Morzhukhina S.V.. Atmospheric deposition of heavy metals and radionuclides in Irtush areas of Kazakhstan. The 31st Task Force Meeting of the UNECE ICP Vegetation (March 5-8, 2018, Dessau-Rossblau, Germany), p. 74.

Speaker: Ms Aipara Kabylova (Dubna Uni)

40 Atmospheric deposition studies based on a 20-year period of moss biomonitoring in the vicinity of a lead-zinc plant in Kardzhali, Bulgaria (1995/6-2015/6)

In 2015, for the fifth consecutive time Bulgaria participated in the moss survey carried out in the framework of the UNECE ICP Vegetation (United Nations Economic Commission for Europe, International Coopeative Programme on Effects of Air Pollution on Natural Vegetation and Crops). Over the years, the areas studied included several 'environmental hotspots', one of which was a hazardous industrial enterprise – the Kardzhali lead-zinc smelter. It was known to be the main source of lead, cadmium, zinc, and sulfur oxide contamination in the country. An overview of the available data was made to reveal temporal and spacial deposition trends for the investigated metals and metalloids during the 20-year period of participation. Throughout the surveys, three analytical techniques were used: neutron activation analysis, atomic absorption spectrometry, and inductively coupled plasma-atomic emission spectrometry. Up to 47 elements were determined in 2005/6, 2010/11 and in 2015/16 (Ag, Al, As, Au, Ba, Br, Ca, Cd, Ce, Cl, Co, Cr, Cs, Cu, Dy, Fe, Hf, Hg, I, In, K, La, Li, Mg, Mn, Mo, Na, Nd, Ni, P, Pb, Rb, Sb, Sc, Se, Sm, Sr, Ta, Tb, Th, Ti, Tm, U, V, W, Yb, and Zn). The results were anticipated to be an extension to the available data on a small number of elements investigated by the State regulatory bodies. A temporary shutting down of the production processes took place during the 2010/11 moss survey, as a penalty for failure to observe the state environmental policy. Thus, it could be assumed that biomonitoring took place around the time when the deposition rates from the emissions were the highest, and then continued through 2015/16, while there was no industrial output. Soon, the smelter in Kardzhali is going to re-open after a major renovation. The data could be used to assess the new pollution-control equipment efficacy, and for estimation of health and environmental risks, and aid risk-management decisions.

Speaker: Gergana Hristozova (Joint Institute for Nuclear Research)

41 Synthesis of carborane containing compounds as potential agents for boron neutron cancer therapy of cancer

For many years, studies of biochemically active derivatives of carborane have been mainly continue due to the search for more efficient methods of boron delivery to tumor cells for boron neutron capture therapy (BNCT). This is an important work that continues to this day in many laboratories in the world. More recently, it became known that boron clusters have remarkable properties that can be used in the development of drugs, along with the detection of antitumor effects and other types of biological activity that are inherent in some derivatives of carboranes and metal carboranes. One of the most important methods of synthesis in the carborane compounds is organometallic synthesis. By the beginning of this work, a huge amount of carborane compounds was obtained on its basis and the effect of bulk electron-deficient carborane systems on the course and direction of a significant number of reactions was studied. A significant part of these compounds has a number of practically useful properties, and, in particular, high antitumor activity as classical chemotherapeutic drugs, as well as the possibility of their use as drugs for boron neutron capture therapy of cancer. In this research, novel nitro-containing carborane compounds have been synthesized with potential anticancer activity. Structure of the compounds were elucidated by FTIR and NMR spectroscopy. Moreover, carborane compounds were immobilized on supermagnetic Fe3O4 nanoparticles with average size of 18.9 nm. Attachment of carborane with 21 boron atoms per molecule was carried out through the ionic interaction of carborane borate with amino groups of modified Fe3O4 NPs. The process of functionalization was controlled by FTIR, TEM, SEM, XRD, DLS and Mössbauer spectroscopy.Biocompatibility was evaluated in-vitro using cultured mouse embryonic fibroblasts (MEFs). The results shows us increasing of IC50 from 0.110 mg/ml for Fe3O4 NPs to 0.405 mg/ml for Fe3O4-Carborane NPs. Obtained data confirm biocompatibility and stability of synthesized NPs and potential to use them in BNCT.

Speaker: Ms Lana Lissovskaya (Igorevna)

42 A novel 111In production by irradiation of Sb target with high energy protons (600 MeV) for further Perturbed Angular Correlation measurements

In present work, 3-step separation scheme using ion-exchange chromatography of 111In purification is performed. 1 g of Sb target was irradiated with 600 MeV protons at 1 µA current for 3 hours at the Phasotron facility (DNLP JINR). The activity of desired radionuclide at EOB equaled 53 MBq//µAh. The separation factor at each step was estimated to be 10^3. Along with 111In purification, 119mTe/117mSn separation is presented. 111In (T1/2= 2.8 d) is one of the most used radionuclides in diagnostics, also one of the most suitable isotopes for γγ-Perturbed Angular Correlation (PAC) measurements due to its parameters: t1/2 = 85 ns, I= +5/2, Q= +0.68, µ= -0.7656, cascade 171-245 keV [1]. γγ-PAC is a unique method in investigation of the local environment of the probe in liquids especially with a chelator in the system [2]. Moreover, required concentration of the probe is up to 10^(-12) mol/l which makes this technique very useful for measuring the precursors of the radiopharmaceuticals being used in Nuclear Medicine [3]. [1] A. Jancso et al., “TDPAC and β -NMR applications in chemistry and biochemistry,” J. Phys. G Nucl. Part. Phys., vol. 44, no. 6, p. 064003, 2017. [2] L. Hemmingsen and T. Butz, “Perturbed Angular Correlations of γ-rays (PAC) Spectroscopy,” Encycl. Inorg. Bioinorg. Chem., pp. 1–15, 2011. [3] D. V Filosofov, A. F. Novgorodov, O. I. Kochetov, N. A. Korolev, and N. A. Lebedev, “Investigation of the DTPA complex formations of indium and cadmium by a γγ - perturbed angular correlation method,” Jahresbericht, Inst. für Kernchemie, vol. 3, no. 20-02, 2004.

Speaker: Mrs Elena Kurakina (Dzhelepov Laboratory of Nuclear Problems, Joint Institute for Nuclear Research, Dubna, Russia; Department of High-Energy Chemistry and Radioecology, D. Mendeleev University of Chemical Technology, Moscow, Russia)

43 Determination of Equivalent Uniform Doses for patient treated with the technique of Simulataneous Integrated Boost

Radiotherapy, proton- and carbon-ion therapy, and boron neutron-capture therapy (BNCT) are among the treatment methods for head and neck tumors that are used in addition to surgery and chemotherapy. Of the former group, X-ray based radiotheraphy is the most commonly used. Radiotherapy is based on irradiation of tumors with external beams of ionizing radiation. Its aim is to deliver the correct dose of radiation to a PTV (Planning Target Volume), minimizing it in critical organs, such as the brain. Among the possible methods for delivering this dose, the intensity modulated radiotherapy (IMRT) technique is the most promising one and analyzed in this work. It involves the use of several beams of radiation with a simultaneous modulation of their intensity, which allows to obtain the planned dose distribution. Such method is very good in cases when the patient has several separated areas of cancer cells, which require the deposit of different doses in different areas. An example of such situation is a tumor located around the head and neck, with the cancer cells on the two sides of organs such as the brainstem, spinal cord or eyes. A particular method within IMRT, which is ideally suited for treatment of such cases is the Simultaneous Integrated Boost (SIB) technique, in which all treated volumes are simultaneously irradiated with various doses. In this work, the mutual influences of deposited doses using SIB in individual Planning Treated Volumes was evaluated using the concept of Equivalent Uniform Dose (EUD).

Speaker: Mrs Martyna Araszkiewicz (Faculty of Physics, University of Warsaw, ul.Pasteura 5, 02-093 Warsaw, Poland)

44 Modifying effect of different forms of lipid A on the induction in vitro of DNA double-strand breaks in mice hippocampal cells after exposure to ionizing radiation of different quality

The search for new techniques and preparations modifying the radiosensitivity of different organisms' cells by immune system activity modulation is of immediate interest of radiation biology. A promising approach is studying the modifying influence of lipopolysaccharides and their derivatives that are widely used in biomedical research and pharmacology on the realization of radiation-induced effects. Lipid A is one of such agents; it shows high biological activity at low concentrations and can be an immune response modulator. In this work, the modifying effect of different modifications of lipid A — diphosphoryl lipid A (DLA) and monophosphoryl lipid A (MLA) — on the induction of DNA double-strand breaks (DSBs) in mice hippocampal cells after in vitro exposure to 60Co γ-rays and accelerated 15N ions has been studied. It has been found that the DNA DSB yield is linear for both types of radiation. The highest DSB yield was observed after accelerated 15N ion exposure. For both types of radiation, the studied agents have different influence on cells’ radiosensitivity: DLA has a radiosensitizing effect; MLA, radioprotective. It can be suggested that MLA's radioprotective properties are realized due to signal pathway activation involving TLR4 receptors. The kinetics of DNA DSB repair in mouse hippocampal cells after in vitro exposure to 60Co γ-rays and accelerated 15N ions at a dose of 5 Gy under normal conditions has been studied. It has been found that the DNA DSB kinetics has an exponential character, and repair is practically completed after 6 h of post-irradiation incubation for both types of ionizing radiation.

Speaker: Ms Eugenia Kuzmina (LRB)

45 The scavengers of reactive oxygen species TEMPOL and reactive nitrogen species cPTIO enhance chromosome aberrations induced by low‐dose γ‐irradiation

There is significant evidence that, in living systems, the overproduction of reactive oxygen species (ROS) and nitrogen species (RNS) can damage DNA, proteins, cellular membranes and leads to tissue dysfunction. Ionizing radiation is a strong inducer of ROS and RNS. The SOD-mimetic TEMPOL and nitric oxide scavenger cPTIO were found to detoxify efficiently ROS and RNS, correspondingly, protecting cells from the mutagenic and cytotoxic effects of radiation. In the present study, we investigated the effect of these compounds on chromosome aberration induction in human breast carcinoma cells Cal51 exposed to γ-radiation at low and high doses. At high doses (1 and 2 Gy), treatment with TEMPOL resulted in an about twofold decrease in the yield of aberrant cells, which is in agreement with its declared properties. At the same doses of γ-exposure, the nitric oxide scavenger cPTIO had no effect on chromosome aberration yield compared with untreated and TEMPOL-treated cells. However, an inverse effect was observed at a low-dose irradiation (10 cGy). Both scavengers enhance chromosome aberration induction, and this effect was most pronounced when TEMPOL and cPTIO were used simultaneously. In this case, the frequency of chromosome aberrations increased more than 1.5 times. A measurement of the ROS level with CM-H2DCFDA-staining in cells exposed to this dose showed that in the presence of Tempol ROS yield increased rather than decreased. However, at the dose 1 Gy this compound efficiently detoxified ROS and it can explain pronounced protective effect of TEMPOL on chromosome aberrations induction which was observed at high doses. A pro-oxidant effect of nitroxides like TEMPOL was reported and ascribed to the formation of strongly oxidizing oxoammonium derivatives that can be responsible for its genotoxic effect at low doses of γ-irradiation. Hence, reactions with superoxide overproduced at high doses can reduce oxoammonium cation back to its respective nitroxide are anticipated to improve the antioxidative effect of nitroxides.

Speaker: Mr Denis Komarov (Laboratory assistant)

Theoretical Physics: Section 2

Conveners: Dr Anastasia Golubtsova (Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research), Dr David Edwin Alvarez Castillo (Joint Institute for Nuclear Research)

46 De Sitter space and Entanglement

De Sitter space, unlike its negatively curved relative, consists of two disconnected boundaries and a causally disconnected interior. In this paper, we argue that the connectedness properties of de Sitter space naturally encode the notion entanglement. We propose an holographic description of an inertial observer in terms of a thermofield double state in the tensor product of the past and future Hilbert spaces, whereby the Gibbons--Hawking formula arises as the holographic entanglement entropy between the past and future conformal boundaries. When considering the entanglement between the two interior Rindler wedges, we show--with no need of holography--that the entanglement entropy between two antipodal and causally disconnected observers is given by a quarter of the area of a pair minimal surfaces. These surfaces are the set of fixed points of an $S^2/Z_q$ orbifold and their total area, when restricted to a single Rindler wedge, reduces to the area of the cosmological horizon (hence recovering the Gibbons--Hawking area law).

Speaker: Mr Felipe Diaz (Universidad Andres Bello)

47 Vacuum fluctuations for a charged scalar field in de Sitter spacetime with compact dimensions

We investigate the vacuum expectation values of physical observables for a charged scalar field in de Sitter spacetime with an arbitrary number of toroidally compact spatial dimension and in the presence of a brane. Quasiperiodicity conditions with arbitrary phases are imposed along compact dimensions and on the brane the field obeys Robin boundary condition. It has been shown that the vacuum expectation values of the field squared and the energy flux density are even periodic functions of magnetic fluxes enclosed by compact dimensions with the period equal to flux quantum. Also the behavior of the expectation values in various asymptotic regions is investigated.

Speaker: Mr Davit Simonyan (Yerevan State University)

48 Bimetric gravity from the spectral point of view

Bimetric gravity models originated from the ghost-free Hassan-Rosen theory are known as a possible extensions of the standard cosmological model. These models are characterized by an action that contains few free coefficients which combinations can be used to define parameters that characterize cosmological scenarios.Since even slight change in these parameters may have a huge impact on the resulting scenario and therefore it is crucial to have an explanation of the origin of these at first sight free parameters. We propose a new method to determine these ambiguous freedom that is originated from the Connes’ noncommutative geometry and previously used in the context of Lott’s cosmology and also for the Standard Model of Particle Physics. We propose to use the tools of spectral geometry to determine relations between parameters in the bimetric gravity models using the geometric construction of spectral triples and methods of Wodzicki residuum computation for generalized Dirac operators. The main ideas will be presented together with some preliminary results. This is still work in progress, so the presentation will be mostly dedicated to the overview of the method rather than the computational results.

Speaker: Mr Arkadiusz Bochniak (Institute of Physics, Jagiellonian University)

49 Chameleon mechanism in inhomogeneous astrophysical objects

Observational evidence implying the accelerated expansion of the universe has been the motivation to develop various classes of modified gravity theories. One of them uses the so-called "screening mechanism", which is successful in reproducing the observed gravitational behavior in large scales as well as being in agreement with tests of general relativity in the solar system. In this work, we investigate an example of scalar-tensor theories with screening mechanism, namely the profile of a chameleon field around inhomogenous astrophysical objects. According to [2], one can define two kinds of approaches applicable to the thin shell and thick shell regimes, that allow for a solution to the chameleon equation of motion. For sufficiently large objects, the scalar field can be assumed to propagate from a thin shell of the object instead of the whole body, which simplifies problem. On the other hand, this solution is not practical in small objects. We find that in inhomogeneous objects this is not necessarily true and at least one more factor, which turns out to be the density, can change the way of approaching this problem.

Speaker: Ms Noshad Khosravi Largani (Alzahra university)

50 Cylindrical curves and classical paths of irreducible massive spinning particles in 4D Minkowsky space

We study the dynamics of classical spinning particles such that quantization of classical model leads to an irreducible massive representation of the Poincare group from the viewpoint of recently proposed world sheet concept [1]. The class of gauge equivalent classical particle paths is shown to form a cylindrical surface in Minkowski space, irrespectively to any specifics of the classical model. The radius of cylinder is fixed by representation. Proceeding from the fact that the world lines of irreducible classical spinning particles are cylindrical curves, while all the lines are gauge equivalent on the same world sheet, we deduce the classical equations of motion for particles. It is shown that the spinning particle’s path is defined by two fourth-order differential equations. These equations define the particle path in Minkowski space, and they do not involve auxiliary variables. The main results of the talk are published in [2]. [1] Kaparulin D.S. and Lyakhovich S.L. // Phys. Rev. D. -2017. -V. 96. -P. 105014 [2] Капарулин Д.С., Ляхович С. Л., Ретунцев И.А. // Известия высших учебных заведений. Физика -2018. -Т. 61. -№12. -с. 3-10

Speaker: Mr Ivan Retuntsev (Tomsk State University)

51 Green’s function technique for precise calculation of false vacuum decay rate.

False vacuum decay is an interesting physical process that recently attracted a lot of attention due to the possible metastability of the electroweak vacuum in the Standart Model at large energies. If it is true than the universe will eventually tunnel in some other energy state with other particle masses and possibly other laws of physics. In this regard, it is useful to study in detail the metastable vacuum decay in high precision. In this work we use the Green’s function technique to calculate one and two loop radiative corrections to the false vacuum decay in quantum field theory with a single scalar field. In order to get analytical result we use the thing wall approximation. In this work we use dimensional regularization and in two different renormalization schemes: Coleman-Weinberg and MSbar.

Speaker: Mr Maxim Bezuglov (JINR)

52 Stable interactions between higher derivative extended Chern-Simons and charged scalar field

We consider inclusion of interactions between two different derived field theories. One of them is supposed to be gauge invariant. At free level, the wave operator of derived-type theory is the polynomial of the primary operator that is of the lower order. Every symmetry of the primary operator results in series of higher order symmetries of the field equations of the derived model that, in its turn, gives rise to the series of independent conserved tensors. Particularly, the translation invariance of primary operator results in the series of conserved tensors of the derived theory including canonical energy-momentum. Even if the canonical energy is unbounded, the other conserved tensors in the series can be bounded. If such bounded conserved quantities exist, the theory is considered stable. In this case, we can include stable interactions with inevitably non-Lagrangian interaction vertices. The general construction is exemplified by the most general gauge invariant extended Chern-Simons theory of arbitrary finite order coupled to the Pais-Uhlenbeck-type higher derivative complex scalar field.

Speaker: Ms Victoria Abakumova (Tomsk State University)

Excursion: Superheavy elements factory

Convener: Mr Alexey Voinov (FLNR JINR)

Poster session

Convener: Mr Anton Dolzhikov (JINR)

53 "The properties of excited states in Ni-63 populated in (n, γ) reaction"

Nuclides in the vicinity of double magicity have simple structure, which can be described with the shell model. The nuclei is treated like closed, well bounded core, built with magic number of nucleons, and walence nucleons. The excitation-energy spectrum is dominated by single particle extitations. Therefore, there is a great need of systematic investigation of the nuclear structure of the nuclei in this area, it is crucial to understand how the nuclear structure evolve with addition of susbsequent nuleons. Obtaining Ni-63 decay scheme is part of those systematic investigations. The experiment was performed in Institut Laue–Langevin (ILL) in Grenoble . Excited states of Ni-63 were populated in (n,γ) reaction. During the data analysis there were 9 new or confirmed γ ray transitions found. One excited level proposed within previous investigation of the Ni-63 was unsobserved in the analysed dataset. The branching factors were calculated for all γ ray transitions. Additionaly, shell model calculations with using different effective interactions were performed and compared to the experimental results. This work was done in EXILL collaboration.

Speaker: Ms Ewa Adamska (Faculty of Physics, University of Warsaw)

54 Beta decay of the very neutron-rich nucleus 85Ge

Beta decay of very neutron-rich nucleus 85Ge (Z=32, N=53) was studied at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory. A high-purity beam of 85Ge was obtained by combining two-stage electromagnetic separation with ion-source chemistry. The partial level scheme with several new transitions in the daughter nucleus 85As was proposed for the first time. The low-energy level structure of 85As was interpreted within the shell model framework. To comprehend the evolution of the level structure in N=52 isotones, the shell model calculations were extended to the neighboring 81Cu, 83Ga and 85Br nuclei. According to them, the increasing number of protons leads to a change of the expected ground-state spin values. This suggests that strong competition may appear between πf5/2 and πp3/2 proton single-particle orbitals for N=52 isotones.

Speaker: Ms Monika Piersa (Faculty of Physics University of Warsaw)

55 Calculation of the neutron spectrum shape that has formed in the neutron generator target by taking into account fluctuations of ionization losses and multiple scattering of D and T ions on the target atoms.

The d(t,n)4He neutron production reaction model was created in Geant4 by reason of the work on the study of modern neutron generators properties. The study of the created model showed a discrepancy between the data on the specified reaction cross sections in Geant4 with the real values that are given by ENDF databases. It was also found that Geant4 tools do not allow to take into account the slowing down process of D and T ions in the generator target. In this regard, an analytical model was developed and created that allows calculating the neutron spectrum shape, and taking into account the main processes of interaction of D and T ions with the neutron generator target substance (fluctuation of ionization losses, multiple ion scattering, energy dependence of the nuclear reaction cross section). This model is a program code in C ++ and can be used with any programming environment. In this case, the Clion environment from JetBrains was used. Comparison of the results that given by created model with the results obtained in [1, 2] showed good data convergence. In [1,2], similar results were obtained using such specialized programs as SRIM-2013 (The Stopping and Range of Ions in Matter) and MCNP (Monte Carlo N-Particle Transport Code). With this in mind, we can say that the created analytical model allows one to obtain sufficiently accurate data of the neutron spectrum at the exit of a neutron generator target, without using specialized and hard-to-reach programs. In the future, it is planned to use the developed analytical model for solving problems of monitoring parameters of neutron generators. In particular, it is supposed to use this model in the task of analyzing the fine structure of the neutron spectrum at the exit of the neutron generator target. To solve this problem, detectors based on a diamond single crystal are currently used. The model created in this work has been improved and now also allows to obtain theoretical forms of the responses of a diamond detector to neutrons from the d(t,n)4He reaction. It should be noted that this model allows to obtain the response shape of a diamond detector only for the spectral region, which corresponds to the reaction 12C (n, a) 9Be. 1. Shorin V.S. Features of the D+T neutron spectra for thick targets PROBLEMS OF ATOMIC SCIENCE AND TECHNOLOGY value 1-2, 2011-2012 p.27-36; 2. D. Rigamonti et al Neutron spectroscopy measurements of 14 MeV neutrons at unprecedented energy resolution and implications for deuterium–tritium fusion plasma diagnostics Meas. Sci. Technol. 29, 2018;

Speakers: Mr Ilya Urupa (National Research Nuclear University MEPhI (Moscow Engineering Physics Institute)), Renat Ibragimov (National Research Nuclear University MEPhI (Moscow Engineering Physics Institute))

56 CALIBRATION OF THE NEUTRON MONITOR

The helium-3 proportional counter employed as a neutron monitor, has components of single helium-3 counter and moderator (polyethylene, paraffin). The helium-3 in this detector is responsible for capturing thermal neutrons that produce tritium and protons in the working gas. GEANT4 program is necessary to find the detector efficiency due to the helium-3 capture of neutrons, which can then be used for calibration of the detector. In finding the efficiency we used GEANT4 to model the detector and find the efficiency as a function of neutron energy. GEANT4 is a program that allows input of the system geometry and materials (moderator and helium3), radiation source and geometry. We had a certain number of neutrons of a given energy aimed at the detector alone and coming from a source. We looked at the number of neutrons that captured in counter out of the total number of neutrons, and plotted the results as a function of energy.

Speaker: Mrs Aidana Assylova (jinr)

57 Carbon nanostructures for drug delivery systems

Since carbon nanotubes (CNTs) discovery in the early 1990s, they have become an area of a wide ranging research activity due to their exceptional chemical and physical properties. The development of new and efficient drug delivery system has fundamental importance to improve the pharmacological profiles of many classes of therapeutic molecules. Many different types of drug delivery systems are currently available. Within the family of nanomaterials, CNTs have emerged as a new alternative and efficient tool for transporting and translocating therapeutic molecules. CNTs possess many intriguing features that make them attractive drug delivery carriers. Doxorubicin hydrochloride (DOX), an anthracycline ring antibiotic, is a highly effective anti-neoplastic agent used in leukemia chemotherapy. However, the severe toxic side effects such as cardiotoxicity, alopecia, vomiting, leucopenia and stomatitis have hampered the successful use of DOX. To reduce the undesired effects without reducing drug potency, DOX is usually encapsulated into drug delivery vehicles that have the ability to protect the molecule of interest and selectively target specific compartments without adversely affecting the surrounding tissues.

Speaker: Mrs Assel Nazarova (JINR, FLNP)

58 Charge suscetptibility in t-J-V model

We have considered behavior of the static and dynamic charge susceptibilities in a system of electrons with strong correlations in the framework of the t-J-V model at various hole doping. In contrast to other works where the dynamical susceptibility was calculated in the random-phase-type approximation using the representation for the density operator as a product of single-particle operators we employ an original representation for the density operator and have calculated the collective density-density GF. An exact representation for the dynamic charge susceptibility was derived within the projection method for the relaxation function. The memory function, both its real and imaginary parts, were calculated in the self-consistent Born approximation.

Speakers: Prof. Nikolai Plakida (BLTP_JINR), Mr Tung Nguyen (BLTP-JINR)

59 Determination of the chemical composition of medieval ceramic vessels found in Bolgar using the neutron activation analysis

The work is devoted to the first application of neutron activation analysis (NAA) to determine the chemical composition of the molding mass of archaeological ceramics. For the research of the Institute of Archeology of the Russian Academy of Sciences, 15 fragments of medieval vessels were presented from the city of Bolgar, the capital of Volga Bulgar (now the territory of Tatarstan). NAA was carried out by a group of NAA installations of IREN in the Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research. The results obtained, previously unknown to researchers of medieval ceramics. Prospects for the use of NAA in archeology are promising due to the fact that this method is multi-element and has a sensitivity exceeding the sensitivity allows to obtain data on the chemical composition of ceramic materials. A neutron activation analysis of relative and absolute methods was conducted, as well as an X-ray fluorescence analysis of the samples were obtained.

Speaker: Ms Ayazhan Zhomartova (MEPHI National Research Nuclear University)

60 Determination of the content of major and trace elements in sedimentary rocks based on instrumental neutron activation analysis

Recently, neutron methods play an active role in investigating diverse aspects of geochemistry, related mainly to the determination of the content of various elements in rocks. Knowledge of the elemental composition of rocks lets simple information about their origin. For this target at the Joint Institute for Nuclear Research (JINR) in Dubna, studies have been conducted to determine the distribution of major and trace elements in geological material collected in the south-east end of the Greater Caucasus. Quantitative determination of the content of elements in the studied rocks, was performed with helping instrumental neutron activation analysis utilize the research reactor IBR-2 in the Frank Laboratory of Neutron Physics. The obtained experimental results were interpreted in the Upper Continental Crust (UC), Mid-ocean Ridge Basalts (MORB) and North American Shale Composite (NASC) model systems. This allowed getting a multitude of information about the origin of the investigated samples, as well as about the the geological environment were the sampes were collected.

Speaker: Mr Fuad Aliyev (JINR FLNP)

61 Determination of the total efficiency of registration of reaction products at the MASHA setup

Determination of separation efficiency of mercury and radon isotopes for MASHA setup is presented in this work. Two experiments by using the fusion reactions 40Ar+144Sm and 40Ar+166Er,Ebeam=5-7 MeV/n, were carried out. In the first experiment the absolute cross sections of evaporation residua (radon and mercury isotopes) were obtained. In addition the absolute cross sections for p(xn) and alpha(xn) reactions were also measured. In the second experiment the total efficiency of MASHA setup for mercury and radon isotopes were determined by using the same reactions.The method of moving absorber made of ultra thin aluminium foils, where the reaction products were stopped, was used. The alpha decay of synthesized isotopes was detected by silicon detectors. Energy resolution of alpha-radioactive isotopes was ~ 100 keV. Time moving of aluminium absorbers between two extreme positions was 0.3 s. The using of beam interruption method allowed to measure half-life of synthesized nuclei. As a result the method allowed reliable identification of reaction products.

Speaker: Ms Eleonora Kudaibergenova (JINR)

62 DEVELOPMENT AND MANUFACTURE OF A MUON DETECTOR.

The results of the development of different types of detectors and the analysis of the results are presented. The types of detectors based on a scintillation counter, Geiger counter, digital matrix were developed and manufactured.

Speaker: Ruslan Marzhokhov (Borisovich)

63 Effect of neutron excess on the single-particle structure of silicon and sulfur isotopes

Characteristics of nuclei far from the stability line are of particular interest. The predictions of regular nuclear models that give similar results for stable isotopes can vary greatly with an increase of neutron excess. Therefore, experimental data for neutron-rich nuclei and the chains to which they belong are extremely important. In this paper, we consider chains of silicon and sulfur isotopes with even values of A = 24÷42 and A = 28÷46, respectively. These isotopes hold great interest for astrophysics research. For stable even isotopes 28,30Si and 32,34S the position of single-particle states can be estimated from the experimental data of one-nucleon transfer reactions. The data about pick-up and stripping reactions are often gained from different experiments. Therefore, we used complementary analysis to find the best agreed pairs of experiments. The calculations of the energy levels are based on the known nucleon separation energies and the excitation energy centroids. To describe single-particle states in unstable neutron-rich isotopes, instead of energy centroids, the energies of the first excited states in the neighboring odd isotopes were used. But still the information about shell occupancy of stable isotopes helps to describe characteristics of unstable nuclei. This calculation scheme was used earlier to determine the single-particle structure of the 2s1d shell in silicon isotopes. The position of the proton levels varies greatly due to a significant change in the central potential. At the same time the energy of the neutron states remains almost unchanged. It seems that the excess of external neutrons balances the effect of the potential change with an increase in the total number of nucleons. The results of experimental data evaluation were compared with a model data.

Speaker: Mr Ilya Dashkov (Lomonosov Moscow State University, Moscow, Russian Federation)

64 Electric dipole response of neutron-rich calcium isotopes in relativistic quasiparticle time blocking approximation

New results for electric dipole strength in the chain of even-even Calcium isotopes with the mass numbers A = 40 – 54 are presented. Starting from the covariant Lagrangian of Quantum Hadrodynamics, spectra of collective vibrations (phonons) and phonon-nucleon coupling vertices for J ≤ 6 and normal parity were computed in a self-consistent relativistic quasiparticle random phase approximation (RQRPA). These vibrations coupled to Bogoliubov two-quasiparticle configurations (2q⊗phonon) form the model space for the calculations of the dipole response function in the relativistic quasiparticle time blocking approximation (RQTBA). The results for giant dipole resonance in the latter approach are compared to those obtained in RQRPA and to available data. Evolution of the dipole strength with neutron number is investigated for both high-frequency giant dipole resonance (GDR) and low-lying strength. Development of a pygmy resonant structure on the low-energy shoulder of GDR is traced and analyzed in terms of transition densities. A dependence of the pygmy dipole strength on the isospin asymmetry parameter is extracted.

Speaker: Mrs Irina Egorova (JINR)

65 Forward-backward assymmetry in processes of electron-positron annihilation into a pair of charged pseudoscalar mesons

Forward – backward asymmetry in the processes electron-positron annihilation into charged pions or kaons at low energies is considered. This asymmetry appears due to quantum corrections. New calculations are performed and differences from formulae available in the literature are established. A comparison with experimental data obtained at the VEPP-2000 collider in Novosibirsk for energies near the threshold for the meson pair production is carried out.

Speaker: Mrs Gulnazym Seilkhanova (BLTP JINR)

66 Friction coefficient determination by electrical resistance measurements

We designed and present in the following an alternative method for measuring the coefficient of friction between two surfaces, using a conductive rubber cord as a force sensor, with it’s electrical resistance being dependent on the force and tension in the rubber cord. The advantage of the method is that it is cheap, fiable and easy to realize, properties which are provided by the Arduino programmable interface and board and thanks to this it also provides high quantities of data. The research project had several steps and components: the calibration of the electrical conductor rubber cord force sensor; writing the code for driving the stepper motor and for reading data from the sensors; realizing the experiment itself and acquiring the experimental data; respectively the analysis and interpretation of the experimental data, drawing the conclusions of the project, and also identifying the possibilities of enhancing and further developing this research. Our work is indented, first of all, to High School and/or University level laboratory projects, but the perspectives of further developing the experiments and our system encourages us to think and work on the implementation possibilities for studying more advanced systems, such as complex dynamic systems, modeling of various phenomena and other similar experimental setups in the near future.

Speaker: Mr Konrad Kandrai (Babes-Bolyai University, Cluj-Napoca, Romania)

67 Heavy ion beam diagnostic of MASHA setup

Implementation and testing of new beam diagnostics for modernized MASHA setup is presented in this work by using the high-speed digitizers and high-speed digital I/O modules based on PXI and PXIe standards from XIA, Agilent and National Instrument companies. The software system for beam diagnostics written in C/C++ was also developed and implemented. The new system was tested in the experiments on the beam with heavy ions at cyclotron U400M in complete fusion reactions: 40Ar + 144Sm, 40Ar + 166Er. Two independent methods are used for energy measurement of the beam. The first one uses two pick-up detectors (energy resolution ~ 1%), the second one includes two MCP and one silicon detectors (energy resolution ~ 0.5%). Due to the new system all parameters concerning the beam diagnostics (beam energy, beam intensity, isotope identification and so on) are written directly into data word of DAQ, which is very important for reliability of experimental results especially in so rare processes like synthesis of heavy and su-perheavy elements.

Speaker: Ms Assylkhan Seitkali (JINR)

68 Interaction of 11Li and 9 Be in the framework of the time-dependent Schrodinger equation

Neutron transfer and nucleus breakup cross sections in 11Li+9Be reaction are calculated at energy range up to 32 MeV/nucleon. The evolution of probability density of external weakly bound neutrons of 11Li and the probabilities of neutron transfer and nucleus breakup are determined based on a numerical solution of the time-dependent Schrodinger equation. Our calculation results are agree with the experiment.

Speaker: Mr Aidos Azhibekov (L.N. Gumilyov Eurasian National University)

69 Investigation of changes of physical properties of Mo-Cu-Diamond material collimator irradiated with a 35 MeV proton beam

Practically all materials from which various structural units and working parts of nuclear and thermonuclear facilities are made, both research and industrial, are exposed to radiation and radiation from various high-energy particles [6] during their work. Radiation, acting on materials, change their structure, and hence their strength, electrical and other properties. It is necessary to carry out tests for irradiation with various fast particles and to investigate changes in the microstructure and mechanical properties at different temperatures and doses of irradiation to understand the physical mechanisms of radiation resistance of ODS materials. The results of irradiation of molybdenum-diamond collimator materials of different sizes on the cyclotron of NRC “Kurchatov institute”at different doses at room temperature for measurements of thermal conductivity coefficient, the thermal expansion coefficient (CTE, α), thermal conductivity (λ) and specific resistivity (ρ) of these irradiated materials are presented.. The materials of molybdenum-diamond collimators were irradiated with protons up to 35 MeV on the cyclotron of NRC KI at low temperature (below 100 ºC) and various doses: F1= 1017 p/cm2, F2 = 1018 p/cm2. Measurement temperature should not be higher than those one for irradiation to prevent radiation defects from annealing. The measurements we performed up to 120 °С after first irradiation and up to 200 °С for the second one. The SRIM-2008 program was used to estimate the rate of formation of defects and proton ranges in the irradiated materials. Since both materials are non-uniform, their damageability was evaluated in two ways: by the average density of the material and for the material, which is alternating layers of metal and diamond in the direction perpendicular to the propagation of charged particles. The latter approach is due to the fact that high-energy protons in the process of propagation in materials weakly deviate from the initial direction, since they spend energy mainly on ionization. Since the mileage of protons in the molybdenum composite is about 2 mm, the samples were irradiated from both sides alternately. The dose uniformity in the irradiation zone was controlled after irradiation by the gamma value of the induced activity. Based on the estimated value of the path (2–2.5 cm) in the irradiated materials for protons with an energy of 35 MeV, which indicates a large number of such layers, the fact of the initial penetration of protons into one or another layer was not taken into account. For irradiation at each dose, NRC KI used three different samples of molybdenum-diamond (one point) to change the thermal conductivity (λ) of irradiated specimens of cylindrical molybdenum-diamond with a diameter of 10 mm and a thickness of 4 mm. Researches of the samples after the 1st and 2nd irradiation with fast protons were carried out to measure the value of the coefficient of thermal expansion of the CTE (α). Three samples with length 16 mm and cross-section 4x4 mm2 were irradiated. Three samples with cross-section 4x4 mm and 16 mm length were chosen for measurements of thermal conductivity. The samples were irradiated with 30 MeV protons in the cyclotron of Ф1 = 1017. Irradiation was performed in a water flow at temperature 70-100 оС up to a dose 1017 p/cm2. Second irradiation was performed to a dose 10 times higher, 1018 p/cm2. Magnitude of specific resistivity for Mo-Cu-Diamond samples was measured using “ampere-voltmeter” technique. In this method, voltage is applied to the sample ends via current contacts, while measured voltage is monitored from the side of the sample through potential contacts separated by 9.4 mm from each other. The measurements were carried out on 3 samples of molybdenum-diamond with a parallelepiped shape of dimensions: 60 mm x 5.5 mm x 4 mm at room temperature. It was found that thermal conductivity (λ) of Mo-Cu-Diamond material is significantly lower than the same value for Cu-Diamond (approximately 1.5 times). Corresponding values at 200 оС equal to 40-45 mm 2/c and 55-95 mm 2/c. It was established that the value of specific resistivity in non-irradiated samples significantly differs from 8.5·10-8 Ohm·m to 11.0·10-8 Ohm·m. The value of specific resistivity for Mo-Cu-Diamond samples has increased by 30-50 % after irradiation. Besides this, it should be noted that the value of specific resistivity for Cu-Diamond samples is significantly lower (an order of magnitude), than those one for Mo-Cu-Diamond samples.

Speaker: Mr Alexander Sluchevskiy (NRC “Kurchatov institute”)

70 Investigation of damages in Y3Fe5O12 single crystals irradiated with swift heavy ions using Raman spectroscopy

The Raman spectroscopy method was used to study the radiation damage formed along the path of swift heavy ions in a yttrium iron garnet (Y3Fe5O12, YIG). YIG single crystals have been irradiated with swift Xe and Bi ions with energies of 167 and 715 MeV, respectively. Irradiation was carried out at room temperature in the range of fluences from 1011 to 1013 ions /cm2. Analysis of the Raman spectra showed that for fluence values greater than 1012 ion/cm2 for Xe and Bi ions, the irradiated near-surface layer is completely amorphous, which made it possible to indirectly estimate the effective damage radius from one ion (latent track radius). Measuring the thickness of the amorphous layer in YIG after irradiation with high-energy Xe and Bi ions made it possible to estimate the threshold for the formation of latent tracks. In addition, shifts in the position of peaks in the Raman spectra were recorded depending on the penetration depth of the ions, which indicates the appearance of internal mechanical stresses in the crystals after irradiation. The results obtained in this work is compared with previously obtained direct data (transmission electron microscopy) and indirect methods (Rutherford backscattering spectroscopy, X-ray diffraction).

Speaker: Alisher Mutali (Joint Institute for Nuclear Research)

71 Investigation of the response of PRISMA-32 and URAN facilities to single hadrons using their models

Hadrons are one of the main components of EAS, which is formed at the interaction of high-energy primary cosmic rays (CR) with the atmosphere. A new method has been developed for studying the hadron component of EAS. This method is based on registration of thermal neutrons that are generated as a result of interactions of shower hadrons with atomic nuclei in the atmosphere and at the surface of the Earth, and then thermalized. For registration of thermal neutrons, scintillation detectors based on ZnS(Ag) + LiF or ZnS(Ag) + B2O3 are used. The advantages of such detectors are good speed, high efficiency, ease of use and low cost. At the Scientific and Educational Center NEVOD (MEPhI) in cooperation with INR RAS, PRISMA-32 array (overall area of the facility ⁓ 500 m^2) and URAN array (overall area of the facility is ⁓ 1000 m^2) were created to register the neutron component of EAS corresponding to E ⁓ 10^15 eV energy range of primary particles. To correctly interpret the experimental data obtained from these facilities, it is necessary to carry out model calculations. For this purpose, the models of PRISMA-32 and URAN arrays were done on the base on the Geant4 simulation toolkit. Installations' geometry is close to real conditions. The thermal neutron detector is a thin layer of inorganic scintillator ZnS(Ag) + LiF for PRISMA-32 and ZnS(Ag) + B2O3 for URAN. The physical processes that are used in the model take into account the peculiarities of the interaction of thermal neutrons with matter. Calculations of the response of the installations to pions and neutrons of various energies generated in the roof of the building were carried out. The time distributions of thermal neutrons detected by the detectors were obtained. The influence of the location of the facilities on the response of the detectors was investigated. The obtained simulation results on the temporal distribution of neutrons show a qualitative agreement with experimental data obtained at PRISMA-32 and URAN.

Speaker: Zarina Izhbulyakova (Tagirovna)

72 Low-coherence reflectometry as the technic of random media characterisation in material science and biomedicine

Low-coherence reflectometry (LCR) is one of the most powerful techniques for characterization of random inhomogeneous media. This article presents results of the analysis of stochastic interference signals in the case of LCR probes applied to various scattering systems. Suppression of the stochastic interference modulation in the LCR output signal was studied depending on the probing conditions (the coherence length of probe light, the scan depth). Examples of two modifications of low-coherence reflectometry units (such as the reference-less unit and the conventional interferometric scheme) are given. These units are considered as the tools for evaluation of optical and morphological characteristics of various scattering systems including biotissues and composite materials.

Speaker: Ms Ekaterina Ushakova (Yuri Gagarin State Technical University of Saratov)

73 Measurement of the time of flight of charged particles using the MCP detector

Experiments with radioactive isotope beams become the direction of nuclear physics, which is currently very intensively developed. Using of such beams for modern nuclear physics research is highlighted by some problems, such as obtaining the required intensity beams themselves, accelerating them to the required energy and registering the products of nuclear reactions. The task of recording and further studying the results obtained, due to the complexity of experiments of a similar level (a large variety of reaction channels, the presence of neutron and gamma background, etc.), places special requirements on the characteristics of the recording equipment used. Under these conditions, one of the most efficiently used methods for determining the energy of a particle is the time-of-flight method, in which the energy is determined by measuring the time of flight of a particle of a given distance. An important element of the time-of-flight technique is the start detector, which must have a high temporal resolution, minimal stopping losses when registering heavy reaction products, low sensitivity to the background of light particles and resistance to radiation damage. In our work, the MCP-detector (a detector based on microchannel plates) was chosen as the starting detector. As the primary test results for this setup, a time resolution was obtained. The results of such studies are of practical importance for modern nuclear physics measurements. In particular, it is possible to use the electronic equipment described in the work as part of the data collection system of a nuclear physical installation.

Speaker: Dauren Aznabayev (JINR)

74 Measurements of the spatial resolution of the first straw tube prototype for SHiP Spectrometer Tracker

The poster presents a developing design of the SHiP Straw Tracker (SST) and its detecting elements - straw tubes. Beam Test measurements of spatial resolution performed with the first prototype of the SST straw tube are presented as well.

Speaker: Mr Andrew Zelenov (Peter the Great St.Petersburg Polytechnic University (SPbPU))

75 Measuring of the neutron generator radiation field characteristics by activation detectors

The possibility of determining with activation detectors the spectral characteristics of the neutron generator radiation field was consider in this work. For measuring the neutron yield from a generator target there has been developed a technique that use threshold detectors which made of copper and aluminum and a screen made of cadmium. The experimental neutron yield values that has been obtained with activation detectors coincide with the readings of the certified dosimeter-radiometer, within the limits of error. There was also performed an simulation of this experiments with the Monte Carlo method. A significant effect on the simulation results of the design of the neutron generator and the measurement geometry is shown. The results of the experiment coincide with the simulation results within the error.

Speaker: Yakov Kokorev (National Research Nuclear University MEPhI)

76 Measuring the optical characteristics at the Baikal Neutrino Telescope site

The deep underwater Neutrino Telescope Baikal NT1000 has been deployed in Lake Baikal since 2015. Detector is mainly designed to study astrophysical neutrino fluxes at energies from a few TeV up to 100 PeV. The first stage NT1000 will be an array of 2300 optical modules with an instrumented volume of about 0.4 cubic kilometers, which is planned to be completed by 2020-2021. The properties of Baikal water and a combination of other related circumstances make it possible to create a unique installation in the world practice in sensitivity and angular resolution, opening up new horizons in astronomy and astrophysics. In this work are providing basic information about the NT1000 and the being developed method to measure the optical characteristics at the detector's water medium using a high-power laser light source.

Speaker: Ms Tokzhan Orazgali (JINR)

77 Method for obtaining the hydrosols of detonation nanodiamond with particle size less than 5 nm

Detonation nanodiamond is a commercially available synthetic diamond that is obtained from the carbon of explosives. It is known that the average particle size of detonation nanodiamond is about 4–6nm [1]. There is a size distribution particles in typical hydrosols, so it is possible to separate smaller particles. In this report we suggest a simple smaller nanodiamond separating method. This method based on using a modified centrifugation and dialysis. The method does not require hazardous or rare chemicals and high-energy or specific laboratory equipment. The method allows for the production of the detonation nanodiamond hydrosol with a very sharp distribution in size, where more than 85% of particles have a size ranging 1–4 nm. Obtained particles can be used as a raw material for constructing neutron reflector [2] or for medicine investigations [3]. A.V. Shvidchenko expresses gratitude to the Russian Foundation for Basic Research for its support (grant № 17-03-01217 А). TEM and AFM measurements were performed using equipment owned by the Joint Research Center “Material science and characterization in advanced technology” (Ioffe Institute, St.-Petersburg, Russia) with financial support by Ministry of Education and Science of the Russian Federation (id RFMEFI62114X0007). References: [1] Aleksenskii, A.E. Technology of Preparation of Detonation Nanodiamond in Detonation Nanodiamonds: Science and Applications. Ed. by Vul’ A.Ya., Shenderova O.A. Pan Stanford Publishing, Singapore, 2014, pp. 37-73. ISBN 9789814411271 [2] V. Nesvizhevsky, U. Köster, M. Dubois, N. Batisse, L. Frezet, Alexeï. Bosak, L. Gines, O. Williams, Fluorinated nanodiamonds as unique neutron reflector, Carbon (2018), doi: 10.1016/j.carbon.2018.01.086 [3] Ansari, S., Satar, R., Jafri, M., Rasool, M., Ahmad, W., Zaidi, S. (2016). Role of Nanodiamonds in Drug Delivery and Stem Cell Therapy. Iranian Journal of Biotechnology, 14(3), 130-141. doi: DOI:10.15171/ijb.1320

Speaker: Mr Andrey Trofimuk (Ioffe Institute)

78 Numerical analysis of the particle scattering at finite temperature

t.b.d

Speaker: Любовь Голяткина (Игоревна)

79 Optimum Relaxation Factor for the SOR Method Applied to 9-point Laplacian

This paper presents two different approaches for evaluating the successive overrelaxation (SOR) factor for the 9-point Laplacian obtained after discretizing the classical model problem consisting of two-dimensional Poisson’s equation and the Dirichlet boundary conditions. The first approach is numerical and uses the golden section search method. The second approach gives an explicit formula for the optimum relaxation factor. For the sake of deriving this formula a spectrum analysis is conducted. A theorem which gives the formulae for the eigenvalues of the Jacobi iteration matrix of the 9-point Laplacian is formulated and proven. Formula for the maximum by an absolute value eigenvalue of the Jacobi matrix is given. The results from the two approaches are compared between themselves and with the known results from the literature.

Speaker: Mr Alexander Ayriyan (Laboratory of Information Technologies, JINR)

80 Preparation and Investigation of Morphological and Thermal Properties of High-Density Polyethylene/SiO2 Nanocomposite Films

A. A. Nabiyev1,2, R.S. Ismayilova1, A. Pawlukojc2, 4, M. Bunoiu5, A.K. Azhibekov2,3, A. A. Imamalieva1, A. M. Maharramov1 1ANAS Institute of Radiation Problems, Baku, Azerbaijan 2Joint Institute for Nuclear Research, Dubna, Russia 3L.N.Gumilyov Eurasian National University, Astana, Kazakhstan 4Institute of Nuclear Chemistry and Technology, Warsaw, Poland 5West University of Timisoara, Timisoara, Romania Nowadays polymer nanocomposites are materials of great commercial and economic importance. Especially, high-density polyethylene (HDPE) based nanocomposites. It exhibits a wide range of properties such as lightweight, chemical resistance, flexibility, toughness, good dielectric properties, thermal stability, electrical insulation, heat shrinkable properties, and relatively low cost compared with other plastics, which make it suitable for many applications [1, 2]. Nanocomposite samples of high density polyethylene matrix (HDPE+%SiO2) were obtained by thermal pressing (under a pressure of 15 MPa) at a temperature 165 °C, followed by rapid cooling in water-ice system. As a filler it has been used an amorphous silica dioxide α-SiO2 (Sky Spring Nanomaterials, Inc. Houston, USA) with 20 nm size of spherical particles, specific surface area of S=160 m2/g and density of 2,65 g/sm3 [3]. Thermal and morphological properties of the nanocomposites were investigated using scanning electron microscopy (SEM), differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA).

Speaker: Mr Asif Nabiyev (JINR, ANAS Institute of Radiation Problems)

81 Preparation of gels of a hydrophobically modified polyacrylamide with high molecular weight and high content of hydrophobic units

Associating polymers represent a very interesting type of macromolecular objects, which can self-assemble in aqueous solutions and form complex structures. Hydrophobically modified polymers, which have a hydrophilic backbone and hydrophobic side chains attached to some monomers, form self-assembled structures due to association of their hydrophobic parts into hydrophobic micellar-like domains. In dilute solutions, such polymers can form “flower-like” micelles with a core formed by hydrophobic moieties, and petals comprised of hydrophilic polymer fragments. Upon the increase of polymer concentration, the solutions enter into semi-dilute regime, and a network of bridged flower-like micelles is formed, resulting in the appearance of viscoelastic properties. The goal of this work is to study the formation, structure and mechanical properties of solutions of a hydrophobically modified polyacrylamide (HM-PAA) with high molecular mass, content of hydrophobic units and degree of blockiness. It was shown that HM-PAA with high molecular weight (1300000 g/mol) forms semi-dilute solutions already at very low concentrations (about 0.05 wt.%), which are characterized by gel-like behavior: their storage (G’) and loss (G’’) moduli are independent of frequency in a wide frequency range, and viscosity diverges at low shear rates. The plateau storage modulus of the gels grows with increasing polymer concentration, which is explained by the increase of number of both flower-like micelles and bridges between them. NMR analysis shows that the hydrophobic side chains of the polymer are grouped in blocks of ca. 8 groups along the backbone, and small-angle neutron scattering (SANS) data confirm that around 70 hydrophobic units (e.g. 9 hydrophobic blocks) form one micellar domain. At the same time, the conformation of hydrophilic parts of the polymer in micellar shell is described by a model of a polymer in a good solvent. Addition of surfactant results in the increase of the plateau storage modulus of the gels due to the formation of “hybrid” micelles comprised of surfactant molecules with hydrophobic polymer groups embedded inside them. Acknowledgement. This work was financially supported by the Russian Science Foundation (project № 18-73-10162).

Speakers: Ms Anna Aleshina (Moscow State University), Mr Anton Makarov (Moscow State University)

82 Preparation of the data for further CNN training to atomized and optimized histological researches

This work aims to adapt convolutional neural network for neuromorphological researches of brain tissue. The standard stain Nissle method allows identifying different types of brain cells with damages. The stained histologic sections are investigated for damages in ones using optical microscope. It is important to bear in mind that this research method is rather judgmental and energy intense. Therefore, this work consists analysis free and existing services/platforms that allow studding neural network. Because of such factors as personality trait, physiological make-up of every pathologist it may happen that the neuron would be identified wrong. Therefore, the human factor is important and may have a prominent influence. Consequently, the project is currently important. By this research it is made the preparation data for further recognition of convolutional neural network. The development of such programme code of detection brain cells allows cutting research time shorter, the method is more objective, the calculating is more correct. A faster and more accurate analysis speeds up the process of obtaining the final result in the study of the effect of any factor on the brain structure.

Speaker: Inna Kolesnikova (by friend)

83 Properties of self-assembled gels formed by crosslinked hydrophilic polymer and surfactant wormlike micelles

A.V.Makarov 1, A.L.Aleshina1, A.V. Shibaev1, A.I. Kuklin2,3, O.E. Philippova1, A.R.Khokhlov1 1M.V.Lomonosov Moscow State University, Moscow, Russia 2Joint Institute for Nuclear Research, Dubna, Russia 3Moscow Institute of Physics and Technology, Dolgoprudniy, Russia E-mail: a_makarov@polly.phys.msu.ru One of the most critical properties of surfactant molecules is the ability to self-assemble due to weak non-covalent interactions into micelles, which may have different shapes. Example of such aggregates is long wormlike micelles which interlace and form a network of topological entanglements, which gives viscoelastic properties to the solutions. Mechanical properties of such gels are not always high; but they can be increased by adding a polymer. As a result, a double network of wormlike micelles and polymer chains is formed. Such polymer-surfactant networks may find application in oil recovery as a thickening agent for hydraulic fracturing fluids. The aim of this work is to study the structure and responsive properties of the systems containing mixed anionic/cationic wormlike micelles and hydrophilic polymer. Firstly, it was shown that the polymer single network, as well as the micellar single network, is sensitive to the change of pH. Moreover, for these networks, the pH values at which there is a drop in mechanical properties (viscosity and elastic modulus) almost coincide. However, double networks at the same pH value have high mechanical properties. It is explained by the fact that the wormlike micellar network inside the double network breaks up with the formation of vesicles (as evidenced by SANS). These vesicles stabilize the cross-links between polymer chains (by electrostatic interaction), and the polymer network does not break up. Complete loss of mechanical properties for double networks occurs at a pH value that is significantly lower than for each of the networks separately. Acknowledgement. This work was financially supported by the Russian Science Foundation (project № 19-73-20133).

Speakers: Ms Anna Aleshina (Moscow State University), Mr Anton Makarov (Moscow State University)

84 Radiation-induced long period changes of hippocampal neurons in rats

For spaceflights it is important to consider the radiobiological effects of cosmic radiation on the central nervous system (CNS). During long flight is possible that damage of the central nervous system occurs, which can cause disturbances of the crew’s operator activity during the flight, and that in turn threatens the fulfillment of the entire space mission. We applied 1 Gy/min 171 MeV proton irradiation on Sprague Dawley outbred rats. Open field tests showed statistically significant differences in comparison with control. On first day, the indicator for the orientation-exploratory reaction (OER) is lowered in both periods, the indicator of emotional status (ES) was lowered from 1-3 minutes 1.5 times. On the 7th day the OER index is lower from 1-3 minutes. On day 14, the ES was increased from 4-6 minutes 1.5 times. On both the 30th day and 90th day, the OER index was increased.  The changes in irradiated animals were observed also in the histological study, the number of intact neurons decreased 1.5 times relative to the control in both periods. Modified cells (both altered and dystrophic) in irradiated rats in the hippocampus increased 1.5 times on the 30th and 90th day. There are structural and cognitive changes observed in hippocampal neurons as a result of proton irradiation, which can be harmful in context of human space flight missions.

Speaker: Dr Lalkovicova Maria (JINR)

85 Radionuclide vectors for radioactive gas-aerosol releases of NPPs with WWER and PWR power units

The research focusing on the gas-aerosol releases of 7 European NPPs with Soviet Union design of power units and 40 other European NPPs with PWR power units was conducted. List 1 was created. It consists of all controlled and accounted during observation period radionuclides, which were noted in releases of the researched NPPs. List 1 consists of radionuclides, which existed technical instruments can detect. The List 1 consists of 82 radionuclides in comparison with the IAEA List [1], which consists of 803 radionuclides. List 2 was created. It consists of all radionuclides, which give the main benefit to the total exposure dose under NPP normal operation conditions established before 2017 year. This List (Total NG, 110mAg, 14C, 58Co, 60Co, 134Cs, 137Cs, 3H, 181Hf, 131I, 124Sb, 90Sr, 75Se, 106Ru, 239Pu + 240Pu) is universal for all researched NPPs. List 3 is created. Using this List it is possible to reduce the list of controlled and accounted radionuclides to 20 units (taking into account virtual radionuclide “Total NG“ – to 15 units) in comparison with the Governmental List of 94 radionuclides [2]. List 4 is created. It consists of radionuclides, which give benefit over 99 % of total exposure dose of radioactive releases of 40 researched NPPs with PWR units. This List consists of 12 radionuclides: Total NG (41Ar, 85Kr, 85mKr, 87Kr, 88Kr, 131mXe, 133Xe, 133mXe, 135Xe, 135mXe, 138Xe), 14C, 3H, 131I, 58Co, 60Co, 137Cs, 11C, 90Sr, 134Cs, 110mAg, 124Sb, 65Zn. It is proved that Lists of radionuclides, which give benefit over 99 % of total exposure dose of radioactive releases of soviet design NPPs with WWER-440 and WWER-1000 power units and NPPs with PWR units are equal. Thus it’s possible to make a conclusion that creation of radionuclides processes and radionuclide’ migration and processes of release are equal for WWER and PWR. The common list is created for 47 NPPs with WWER and PWR power units. It consists of radionuclides, which give benefit over 99 % of total exposure dose of radioactive releases. This list includes 27 radionuclides. Nevertheless, it generated a question if 11 radionuclides, which were detected only on 2 % of the researched NPPs, stay legitimately in this List. This question needs additional discussion. List of References 1. Radiation Protection and Safety of Radiation Sources: International Basic Standarts// General Safety Requirements Part 3 № GSR Part 3 (Interim) – IAEA, 2011. 2. Government Regulation No. 1316-P, dated 08 July 2015

Speaker: Ms Angelina-Nataliya Vukolova ("Kurchatov Institute" NRC)

86 Status and perspectives of VEGA-M setup at the MT-25 microtrone for studying of the cluster effects in heavy nuclei.

Motivation and status of the VEGA-M (Velocity-Energy Guide based Array on Microtrone) project is presented. The one armed fission fragments spectrometer with an electrostatic guide system is mounted at the MT-25 microtrone at the FLNR of the JINR. The obtained recently test results are reported.

Speaker: Alexey Solodov (JINR FLNR)

87 STRUCTURE OF THE CARRIER-DRUG SYSTEMS BASED ON FULLERENE

Fullerenes due to pleiotropic activity are promising agent for different medical applications. They are used as a separate active component and as a carrier of modifications in targeted delivery and/or prolonged therapy. The fullerenes water solutions, which were prepared by extraction from C60/NMP, characterized by unique small cluster sizes of fullerenes that lead to improved biocompatibility of fullerenes. Based on the aqueous dispersions of fullerene, it was designed a number of drug delivery system as fullerenes-polyphenols, fullerenes-alkaloids, polysaccharides-fullerenes. These systems were investigated by small-angle neutron scattering, dynamic light scattering, and UV-Vis spectroscopy. In addition, a computer model of carrier-drug interaction was proposed based on quantum chemical calculations.

Speaker: Mrs Maryna Kuzmenko (Frank Laboratory of Neutron Physics Joint Institute for Nuclear Research)

88 Study of archaeological object by neutron resonance capture analysis

Neutron resonance capture analysis is based on the registration of neutron resonances inradiative capture. One of the main advantages of this method is nondestructive property. The investigations were carried out at the Intense Resonance Neutron source (IREN) in Frank laboratory of Neutron Physics. The gamma-quanta liquid scintillator detector was used at this experiment. The analyzed sample, in our case it was horse figurine, was provided by the Institute of Archeology of the Russian Academy of Sciences. The artifact is the silver vessel's handle from the 1 Chebotarev-V excavations burials on the Lower Don (rich female burial). This burial ground dates from the Sarmatian period (about 1st century AD).

Speaker: Ms Saltanat Mazhen (JINR)

89 Temperatures of entrance window and target operating at high intensive heavy ion beams in the future experiments on synthesis of superheavy nuclei

The detailed study of properties of superheavy nuclei (SHN) in the experiments with the complete fusion reactions induced by the 48Ca projectile on actinide target nuclei, which lead to 112≤Z≤118 nuclei, implies the use of heavy ion (HI) beams with the intensity significantly higher than the one used earlier in the discovery experiments with the 48Ca beam. Synthesis of SHN with Z>118 implies the use of the heavier than 48Ca beam particles (50Ti, 54Cr etc.). And also to improve the efficiency of SHN yield, it is necessary to increase the thickness of the actinide oxide deposited onto the target backing. In this report, the durability of the entrance window and target working at high intensive heavy ion beams is considered. The durability of the entrance window and target is estimated as the result of the action of an intense heavy ion beam. The assessments of these actions that determine the durability of the entrance window and target are discussed. The temperature of the entrance window is calculated as a function of time in the conditions of its pulsed heating by means of a heavy ion beam, followed by radiative cooling with radiation emitted from its surface. The entrance window temperatures are calculated for heavy ion beams, such as 48Ca, 50Ti, 54Cr and 58Fe, with their intensities expected for the DC-280 accelerator. With these calculations of the temperature dependences against the time of the beam action the optimal parameters of the entrance window operation are chosen. The optimal rotational speed of the target is determined by varying the thickness of the actinide oxide and radius of the target.

Speaker: Mr Dastan Ibadullayev (JINR, FLNR)

90 The facility for neutron radiography and tomography at the research reactor WWR-K

At the research reactor VVR-K (Institute of nuclear physics, Ministry of energy, Almaty, Kazakhstan) began work on the creation of a new experimental facility for research using neutron radiography and tomography methods. It is planned to form a neutron beam with a cross section of 200x200 mm, with the characteristic parameter L/D equal to 140-1400, using a vacuum collimator system. To obtain neutron radiographic images, a specially designed detector system based on the 6LiF/ZnS scintillation screen and a high-resolution high-sensitivity video camera with a mirror will be used. To protect the camera from radiation it is proposed to use two mirror optical system. This report will present the schematic diagram and description of the main components of the experimental setup.

Speaker: Kuanysh Nazarov (JINR)

91 The magnetic properties of intermetallic cobalt compounds under high pressure

The study of YCo5-xMx (M = Fe, Co, Ni) intermetallides is one of the actual task of condensed matter physics, due to the large variety of physical phenomena found in materials based on them. Such phenomena as the magnetism of collectivized electrons, giant magnetoresistance, magnetocaloric effects (FEM), and the volume collapse of the crystal lattice were found in these compounds, which makes them promising materials for magnetic refrigerators, permanent magnets, etc. The RCo5 and YCo5-xMx compounds crystallize in CaCu5-type structure with space group P6/mmm. In this lattice, the cobalt atoms occupy 2c and 3g sites and form ferromagnetic ordering. These compounds are sensitive to changes in interatomic distances that can lead to significant changes in their magnetic properties and the simultaneous using of high-pressure cells give opportunity to control the changes of the interatomic distances. In our work the results of the investigation of YCo5 and YCo4Si by the method of neutron diffraction at high pressures are presented. The crystal structure and magnetic properties of YCo5 compound have been studied by neutron diffraction, in the pressure range 0 ≤ p ≤ 7.2 GPa at room temperature. A lattice collapse is detected due to a change of cobalt ions spin states from the high spin to the low spin in YCo5. YCo4Si have been studied in a wide range of pressures and temperatures 0 ≤ p ≤ 5.3 GPa and 10 ≤ T ≤ 300 K, respectively. The Curie temperature reducing with same baric coefficients -10 K/GPa for cobalt atoms in both 2c and 3g positions is observed under pressure. The suppression of cobalt magnetic moments in these positions has been found as well. This phenomena is associated with change of cobalt ions spin states from the high spin to the low spin in YCo4Si. This work was supported by the Russian Foundation for Basic Research (project no. 17-02-00112)

Speaker: Mr Anton Rutkauskas (Joint Institute for Nuclear Research)

92 The possibilities of neutron diffraction to study lipid membranes

In this paper, the internal structure of the lipid membrane was investigated by neutron diffraction method. Lipid membrane consists of a mixture of dipalmitoylphosphatidylcholine and cholesterol in a ratio of 80/20 by weight. An important methodological issue was the dependence of the neutron scattering length density ρ(x) on the number of diffraction peaks taken into account in the calculations and their minimum number required to obtain information about the internal structure of the lipid bilayer. To find the answer to this question, the calculations of the function ρ(x) for the different number of diffraction reflection orders taken into account at 8%, 20% and 50% D2O (heavy water) in vapors hydrating the membrane were performed. The use of contrast variation allowed to determine the function of water distribution inside the lipid bilayer in the direction of normal to the bilayer.

Speaker: Mrs Aru Nurkasova (JINR)

93 The results of electron and positron anisotropy study with PAMELA calorimeter

The work is dedicated to study of the anisotropy of the combined fluxes of high-energy cosmic ray electrons and positrons in the PAMELA satellite experiment using a PAMELA calorimeter. As a result of analysis of data, collected by the nearly decade measurements, the upper limits for the dipole anisotropy of the total fluxes of electrons and positrons were established for the two energy ranges: 25-100 GeV and 100 GeV - 1 TeV.

Speaker: Dr Alexander Karelin (MEPhI)

94 Uncertainty and sensitivity analysis of the ANNA critical assembly benchmark using SCALE

Between 1961-1972 four critical assemblies were constructed at the Institute of Nuclear Research (now National Centre for Nuclear Research - NCBJ) in Swierk, near Warsaw known under the names: ANNA, MARYLA, AGATA and PANNA, and one exponential assembly HELENA. ANNA was a graphite-light water moderated assembly with enriched fuel, designed primarily as a mock-up of the high-flux reactor. ANNA consisted of a core, top and bottom reflectors, all surrounded by the radial graphite reflector. The whole system was 240 cm high and its horizontal cross section, octagonal in form, has an equivalent radius of 137.5 cm. The core was composed of 21% U-235 enriched fuel elements immersed in vertical coolant channels passing through a graphite matrix. The coolant channels and the graphite matrix extend throughout the top and bottom reflectors. The first critical experiment was carried out in June, 1963. The Polish Ministry of Energy commissioned the benchmarking of this reactor for the needs of the OECD database “The International Handbook of Evaluated Criticality Safety Benchmark Experiments”. Sensitivity and uncertainty methods have been developed to aid in the establishment of areas of applicability and validation of computer codes and nuclear data for nuclear criticality safety studies. This work presents the determination of uncertainties of effective multiplication factor (k-eff) associated with geometry, masses and compositions of the constituents of the critical assembly. The uncertainty of k-eff, caused by nuclear data, were determined by TSUNAMI/SCALE code, which uses the Generalized Perturbation Theory (GPT) for cross-sections perturbations.

Speaker: Mr Lukasz Koszuk (Faculty of Physics, University of Warsaw)

Wednesday 17 April

Plenary session: Prof. Kazakov Dmitry "At the edge of discoveries in particle physics (worldwide and with JINR participation)"

Convener: Dr Aidos Issadykov (Jinr)

11:00 Coffee break

Plenary session: Dr. Eremin Roman "Computer modeling of disordered crystals"

Convener: Dr Aidos Issadykov (Jinr)

12:30 Lunch

Condensed Matter Physics: Section 2 Part 1

Conveners: Dr Ivan Bobrikov (JINR), Timur Tropin (Joint Institute for Nuclear Research)

95 The study of change of phases and structural, corrosive properties and cytotoxicity of nanoparticles based on the magnetite

Today, magnetic nanoparticles based on metal oxides have great interest by both scientific world and industry. Magnetite Fe3O4, which nanoparticles have wide range of application in different fields of science and techniques, is the most popular form of synthesized nanoparticles. There is huge interest to these nanoparticles due to their adsorption properties, good biocompatibility and superparamagnetic properties. Despite the great potential of the application of magnetic nanoparticles in biomedicine, the concentration degree that results toxicity of nanoparticles is still unclear. The results of the research of dependency of structural and corrosive properties as well as phase transformation from toxicity of nanoparticles based on the magnetite Fe3O4 are presented at this work.

Speaker: Ms Assel Yermekova (Yermekovna)

96 Effect of annealing temperature on the phase state of perovskite systems based on Fe3O4 and CeO2

Introduction. One of the important problems of modern material is the development of new materials with desired properties. Oxide compounds with structural-perovskite properties as a new material with multiple physicochemical properties. Among perovskite systems, materials with dielectric, magnetic, and conductive properties are most often used, which can be used not only in engineering, but also in modern energy. The variety of perovskite compounds is due to the great flexibility. Currently, compounds in the structural composition of ABO3 are well studied, however, the creation of materials in practice differs significantly from the ideal structural perovskite. Variants of defects, which can be fossilized when cations are replaced by crystal structures, make it possible to obtain unique properties that allow the use of perovskites of oxide compounds in various areas. Thus, the study of perovskite systems with different composition and methods of modification. Materials and methods. The paper presents the results of studies of changes in the structure of the perovskite system based on Fe3O4 and CeO2 on the annealing temperature. After mechanical grinding of metal powders in the proportions 1: 1, 1: 2, 2: 1, 1: 3 and 3: 1, thermal separation was carried out in the temperature range of 600°C, 800°C, 1000°C for 5 hours. In a muffle Nubertherm LE / 11 / r6 furnaces.

Speaker: Mrs Dina Mustakhieva (Adilkhankyzy)

97 NEUTRON AND X-RAY REFLECTOMETRY STUDY OF STRUCTURE IN THIN FILMS OF POLYSTYRENE-FULLERENE NANOCOMPOSITES

Thin polymer films have numerous technological applications in various industrial and biomedical sectors[1]. In many cases, the films can be of complex composition with different types of polymers with complex architecture and other components such as nanoparticles. Polymers in thin films and nanocomposite structures can exhibit unusual physical properties due to the geometric constraints imposed by the presence of surfaces and interfaces. Polystyrene-fullerene films present a suitable model system for investigation of these properties. Neutron and x-ay reflectometry have proved to be effective methods for studying PS/C60 thin films, allowing evaluating the structural peculiarities of nanoparticles ordering in the polymer matrix [2]. Several physically based models of structural organization of the nanoparticles in polymer matrix are considered – a uniform distribution, a dense substrate layer, a layer on the surface of a polymer. Our modeling shows that it is possible to apply neutron and x-ray reflectometry for clarifying the structural organization of nanoparticles in the nanocomposites with the mass concentration of fullerenes exceeding 1%. In the present work, we performed study of structure in thin films of polystyrene-fullerene nanocomposites. PS/C60 and PS/C70 solutions in toluene were spin-coated on Si (111) at 2000-6000 rpm after filtering through 0.22 Milipore filter. Series of thin films samples with different concentration of fullerenes were prepared and investigated for the internal structure. Neutron measurements of polymer thin films in the temperature range up to 130°C were performed at the GRAINS instrument of the IBR-2, JINR. For this purpose, a special cell for samples was designed and created. Possible internal structure of films has been analyzed. [1] E.Slaver. Polymer Thin Films, 304 (2016). [2] Yaklin, M. a., Duxbury, P. M., & Mackay, M. E. (2008). Control of nanoparticle dispersion in thin polymer films. Soft Matter, 4(12), 2441.

Speaker: Mr Maksym Karpets (Taras Shevchenko national university)

98 Studies of coins of medieval Volga Bulgaria by neutron diffraction and tomography

Studies of the physicochemical properties of ancient coins are one of the important areas in the non-destructive testing of cultural heritage sites. Numismatic material stores valuable information about the trade, economic and social development of ancient civilizations and states. It is known that the study of the chemical composition and internal structure of coins can provide important information about the deposits of silver or gold ore, from which coins are made, conformity with a specific historical period or features of minting, and identification of fakes. Compared with the methods of X-ray fluorescence analysis, electron microscopy and metallography used in archaeological scientific communities, neutron research methods have high penetrating power into the thickness of metal objects. Since, due to the peculiarities of casting and chasing medieval silver coins, they are characterized by an uneven distribution of chemical components throughout the volume, the use of methods of neutron diffraction, radiography and tomography is justified. Two coins from the territory of the Volga Bulgaria were selected as objects of research: the Samanid multidirham, dating back to the 10th century, and the dirham of Emir Bulat-Timur (late 14th century), referring to the two most active periods of development of commodity-money relations in the region and the maximum distribution in trade metal coin operations. The study of the crystal structure and phase composition of the coins was carried out using the neutron diffraction method on a specialized diffractometer for the study of micro samples DN-6 at a high-flux IBR-2 reactor. Analysis of diffraction data was performed by the Rietveld method using the FullProf program. The spatial distribution of chemical elements in coins was studied by neutron radiography and tomography at a specialized experimental station on the 14th channel of the high-flux IBR-2 reactor. Due to the varying degree of attenuation of the intensity of the neutron beam when passing through components of different chemical composition, it is possible to obtain information on the distribution of phases within the volume of the material under study with a spatial resolution at the micron level. As a result of the work, it was established that both of the investigated coins consist of a copper-silver alloy. However, the multidircham is characterized by a very high content of copper - on average, about 50% of the total volume of the material of the coin. The spatial distribution of silver and copper in this coin is inhomogeneous, which may be associated with both the characteristics of the original ore and the processes of coin minting. Dirham is almost entirely made of silver. The volume content of copper in this studied coin is quite low - 5.2%. Neutron data indicate a uniform distribution of silver in the material of the coin. This may indicate an increase in the quality of the source metal and changes in technology.

Speaker: Bulat Bakirov (JINR FLNP)

99 The high-pressure effect on the crystal structure of cobaltite LaSrCoO4

Recently studies of complex cobalt oxides have attracted wide scientific interest, due to the large variety of physical properties found in these materials. In contrast to manganites or cuprates, cobaltites have a unique feature - the ability to change the spin state of Co3+ ions with variations in thermodynamic parameters (temperature or pressure). So, depending on the balance of comparable in magnitude intra-atomic exchange energy JH and the splitting energy of the crystal field CF, nonmagnetic low-spin LS (t2g6, S = 0), magnetic intermediate-spin IS (t2g5eg1, S = 1) and high-spin HS (t2g4eg2, S = 2) states can be realized in cobaltites. It should be noted that the model layered cobaltite LaSrCoO4, which has only trivalent Co3+ cobalt ions, attracts the attention of researchers by a complex mixed spin configuration of low-spin LS and high-spin HS states. Such a model of the ground spin state of cobalt ions is often debated in opposition to the existence of an intermediate spin IS state in this cobaltite. The effect of high pressure is a direct method for the controlled change in the spin states of cobalt ions due to the variation of interatomic distances and the corresponding valence angles. Studies at high pressures provide a unique opportunity to determine the structural mechanisms of changes in spin states in cobaltites. Detailed studies of the crystal structure of LaSrCoO4 were carried out using neutron diffraction on a DN-6 diffractometer of a pulsed high-flux IBR-2 reactor (FLNP, JINR, Dubna, Russia) using a high-pressure chamber with sapphire anvils in the pressure range up to 5.8 GPa and a temperature range of 7-300 K. The baric and temperature dependences of the unit cell parameters, the volume and the interatomic bond lengths of the LaSrCoO4 compound were obtained. It has been established that the apical and axial Co-O bond lengths are compressed isotopically but the apex Co-O distance reduces faster than that for the in-plane up to 5.8 GPa, namely the ratio Co-O2/Co-O1 decrease with high pressure from 1.06 to 1.039. The LS state could become the ground state when this ratio is larger than 1.065, so for the LaSrCoO4 was observed the HS ground state due to the decrease of 10Dq and of the eg splitting from the reduction of Co-O2/Co-O1. The ratio of the lattice parameters c/a increase with high pressure, so the octahedra is more symmetrical and the LS state become more stabilized.

Speaker: Ms Olga Lis (JINR)

100 Research of the structure of cement materials with the addition of graphite for storage of radioactive waste by neutron radiography and tomography

Nowadays, the question of radioactive waste storage is relevant. Special storages are being created for this which require constant monitoring of structural wear. The new categories of cement are being used for extending the lifestyle of such storage. Particular attention is paid to the corrosion resistance of reinforcing materials of concrete structures under different environmental conditions, as well as their micro pore structure, which is formed at an early stage of solidification of cement . The experimental neutron scattering methods obtained to detailed data on phase analysis or features of the crystal structure, formation of nanoparticles and grains inside the matrix, aging, cracks and pore evolution. They are used to determine the structural characteristics of cement materials and concretes and allow us to understand the nature and origin of the mechanical and chemical properties of cement, predicting the functional properties, presenting ways to optimize the composition of new cement materials. Experiments on neutron radiography were carried out at the installation of NRT, neutron diffraction at the DN-12 diffractometer in the high-flux pulsed reactor IBR-2. The formation of cracks at the point of contact of the aluminum container and cement paste was found. The dependence of the attenuation coefficient of the neutron beam of cement paste over time is constructed. Anomalies in the behavior of neutron beam attenuation realted with the beginning of the process of gas and water vapor release during cement paste solidification were revealed and a lot of pores found inside dried cement.

Speaker: Murat Kenessarin (Старший Лаборант)

101 Mobility of alkali metal atoms in graphene systems with geometric distortions.

One of the limiting factors of the charge/discharge rate of lithium-ion batteries and related systems is the low mobility of alkali metal atoms in the anode material. Graphene-based anode materials can improve this and a number of other characteristics. The mobility of atoms in graphene or other intercalates is determined by a number of characteristics associated with lattice vibrations. In the case of highly disordered graphene, small low-layered structures act as a highly deformed matrix material. This work is dedicated to a theoretical study of the influence of geometry distortion on the mobility of alkali metal atoms in graphene structures. The molecular dynamics simulations have been used to determine the diffusion characteristics of lithium and sodium for a number of single and bilayer structures with different geometric constraints. Significant changes in lattice vibration modes were observed, depending on the nature of the structure constraint. In the case of bilayer structures, this led to a significant isotropy of alkali atoms mobility. This result may be useful for developing advanced batteries and related systems. The work was financially supported by the Russian Science Foundation (grant №17-73-10226).

Speaker: Mr Ruslan Yamaletdinov (NIIC SB RAS)

102 Structural modification of 12-thungstophoshoric acid by ion beam irradiation

Polyoxometalates are a large group of transition metal oxides with characteristic complex structures and interesting physicochemical properties that are important in catalysis, sensing and storage of energy. The 12-thungstophosphoric acid (WPA) is typical heteropolyanion; it is composed of 12 WO6 octahedrons that are placed around central PO4 tetrahedron (PW12O403-). This structure, known as Keggin anion, has multiple redox reactions that are very useful in electrochemical charge storage applications. In present study, we have investigated effects of ion beam irradiation on structural properties of WPA. The WPA films (~120 nm) were irradiated with 10 keV C+ ions at fluencies between 5×10^14 and 2.5×10^15 ions/cm2. As-prepared and irradiated samples were characterized by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy and UV–Vis diffuse reflectance spectroscopy. Characteristic bands of the Keggin anion structure were observed in ATR-FTIR and Raman spectra of as-prepared samples. Shifting and broadening of these bands was observed for irradiated samples, indicating structural changes in WPA. UV–Vis diffuse reflectance spectroscopy of irradiated samples showed changes in the spectra of WPA and increase of band-gap. The obtained results suggest that ion beam irradiation with 10 keV C+ ions at the lower fluencies alters WPA structure while higher fluencies cause amorphization of Keggin anion.

Speaker: Mr Željko Mravik (Laboratory of Physics, Vinča Institute of Nuclear Sciences, University of Belgrade, P.O. Box 522, 11001 Belgrade, Serbia)

High energy physics: Section 1

Conveners: Dr Alexey Aparin (Joint Institute for Nuclear Research), Oleg Samoylov (JINR)

103 The Microscopic Black Hole Production at the LHC with CMS experiment

The work is devoted to the study of microscopic black hole production with the CMS experiment at LHC. One of the predictions of theoretical models with extra spatial dimensions and low-scale quantum gravity is the possibility of production of microscopic black holes in particle collisions, in particular, at colliders. Based on the simulation with the BlackMax and the Charybdis2 event generators, I will present the analyses of different scenarios of microscopic black hole production at the LHC energy of 13 TeV. The obtained values of the cross sections for black holes, as well as for alternative objects of strong gravity (near-threshold quantum black holes, string balls) will be used to establish the experimental observability limits of these effects, which is an important and actual task for the long-term program of LHC on the search for new physics.

Speaker: Ms Diana Seitova (LHEP JINR)

104 Measurment of Angular Coefficients in Drell-Yan process with the CMS experiment at the LHC

The main subject of my reserach is the Drell-Yan process, in particular measurement of the polarization angular coefficients of Z boson which sesnsetive to (V –A) structure of weak interactions and can be indicators of effects from higher orders and QCD twists, as well as the nontrivial QCD vacuum structure. Also measurment of this coefficients is important for subsequent precision measurement of parameters of the electroweak model at the LHC, such as the sine of Weinberg electroweak mixing angle sin2 θ W and the W boson mass.

Speaker: Vladislav Shalaev (JINR, Dubna State University)

105 Simulation of the long-baseline neutrino experiments with Global Neutrino Analysis package

Neutrino physics is a major part of modern science. Now in Dzhelepov Laboratory of Nuclear Problems of JINR, we are developing a global neutrino analysis software (GNA). The main goal of this program is to create some universal way to analyze any kind of neutrino experiments. At first, this problem has been being solved only for reactor neutrino experiments such as Day Bay, JUNO. This talk will be devoted to including long-baseline neutrino experiments into this package.

Speaker: Ms Anastasia Kalitkina (JINR, DLNP, University Centre, MSU)

106 Monte-Carlo study of the Higgs boson production in association with a single top quark at sqrt(s) = 13TeV at LHC

А direct search for the production of a Higgs boson in association with single top quark is performed. The analysis considers single top quark production via t channel and uses Higgs boson decays to a bottom quark-antiquark pair and semileptonic top quark decays. Such process is strongly suppressed in the Standard Model. An observation of this production mode would be an unambiguous indication of the New Physics providing an important insight on the nature of the Higgs mechanism. The production is sensitive to the relative sign of the coupling parameters describing its interaction with fermions and gauge bosons. We present a Monte-Carlo study of the pp → tHqb process and discuss the experimental signatures that can help to discover it at the LHC. Two scenarios have been considered, the Standard Model case and the Inverted Top Coupling scenario.

Speaker: Oksana Koval (JINR)

107 Analysis of the rare decay K+→mu nu mu mu

The main goal of the NA62 experiment at CERN is a study of the ultrarare decay К+ → pi nu nu. The collected statistics allows to analyse other rare decays, in particular, К+→ mu nu mu mu. Rare decays make it possible to experimentally investigate one of the aspects of the Standard Model, the chiral perturbative theory (ChPT). ChPT predicts decay probability of К→ mu nu mu mu: 1.35 х 10^(-8). This decay channel is also of great interest due to the fact, that it was not experimentally observed, there is only an upper limit < 4.1 х 10^(-7) CL 90%. We present the research methodology, the first results of signal selection and the study of the background sources for the decay.

Speaker: Ms Aigul Baeva (JINR,LHEP)

108 Performance studies of anisotropic flow with MPD at NICA

The Multi-Purpose Detector (MPD) at NICA collider has a substantial discovery potential concerning the exploration of the QCD phase diagram in the region of high net-baryon densities and moderate temperatures. The anisotropic transverse flow is one of the key observables to study the properties of dense matter created in heavy-ion collisions. The MPD performance for anisotropic flow measurements is studied with Monte-Carlo simulations of gold ions at NICA energies \sqrt{s_{NN}}=4−11 GeV using different heavy-ion event generators. Different combinations of the MPD detector subsystems are used to investigate the possible systematic biases in flow measurements, and to study effects of detector azimuthal non-uniformity.

Speaker: Mr Peter Parfenov (MEPhI, Moscow)

Slides MPD_CM_15042019.pdf

109 A study of the VH associated production process

Analyzed the experimental data of ATLAS obtained in proton-proton collisions in Run-2 LHC at a centre-of-mass energy of 13 TeV for the period 2015-2017, corresponding to an integrated luminosity of 79.8fb^-1. The Run 2 VH, H → bb result is further combined with the results of other Run 2 searches for the Higgs boson produced in the VH production mode, but decaying into either two photons or four leptons via ZZ decays. For a Higgs boson mass of 125 GeV, and assuming the relative branching fractions of the three decay modes considered to be as predicted by the SM, the observed significance for VH production is 5.3 standard deviations, to be compared with an expectation of 4.8 standard deviations. Assuming the branching fractions are as predicted by the SM, the fitted value of the VH signal strength for all channels combined is: µ = 1.13 ± 0.15(stat.)+0.18−0.17(syst.). These observation is direct evidence of the discovery of associative production of the Higgs boson and the vector boson.

Speaker: Mr Faig Ahmadov (JINR)

110 Primary processing of hits in cylindrical GEM tracker of the BESIII experiment

The inner part of the BESIII drift chamber is expected to be replaced with a cylindrical GEM (CGEM) tracker in summer 2019. Despite providing generally similar performance to the currently installed inner drift chamber, in may improve tracking of the low-momentum charged particles, which is strongly affected by the beam-induced background. Moreover, it can be seen as testing ground for trackers in proposed high event rate experiments like super c-tau factories. For high background and high multiplicity events application of advanced neural network track reconstruction methods may provide gains both in tracking efficiency and reconstruction time. In this talk the very first step, namely primary event processing for the BESIII CGEM subdetector which involves cluster finding and 3d-coordinate hit reconstruction, will be considered.

Speaker: Igor Denisenko (JINR)

Slides Denisenko_AYSS2019.pdf

Nuclear Physics: Section 1

Conveners: Dr Dmitry Testov (JINR), Mrs Yulia parfenova (Joint Institute for Nuclear Research)

111 BINARY BRAKE-UP OF FISSION FRAGMENTS AT CROSSING OF METAL FOILS

In our previous publications [1–3] we discussed new original effect appeared at crossing of the metal foils by fission fragments (FFs). In the series of recent experiments we have compared the mass of the FF before (Mtt) and after (Mte) it passes the foil event by event. In the light of the obtained results, a FF from conventional binary fission is supposed to be born in the shape isomer state which looks like a di-nuclear system consisting of the a magic core and lighter cluster. Comparison of the correlation mass distributions Mtt-Mte for different metal foils is presented aimed at testing possible models of the effect. References 1. Yu.V. Pyatkov et al., Proceedings of the 22th International Seminar on Interaction of Neutrons with Nuclei, Dubna, Russia, 27–30 May 2014. Dubna 2015, p. 83. 2. Yu.V. Pyatkov et al., International Symposium on Exotic Nuclei "EXON-2014", Kalaningrad, Russia, 08–13 September 2014. Conference proceedings, Editors: Yu. E. Penionzhkevich, and Yu. G. Sobolev. Published by World Scientific Publishing Co. Pte. Ltd., 2015. p. 383. 3. Yu. V. Pyatkov et al., Int. Symposium on Exotic Nuclei "EXON-2016", Kazan, Russia, 04-10 September 2016. Conference proceedings, Editors: Yu. E. Penionzhkevich, and Yu. G. Sobolev. Published by World Scientific Publishing Co. Pte. Ltd., 2017. p. 284

Speaker: Mr Alexandr Strekalovsky (JINR)

112 γ emission from neutron-unbound states in 133Sn

The study of 133Sn provides excellent conditions to investigate single-particle transitions relevant in the neutron-rich 132Sn region due to the simplicity of its nuclear structure. After many experimental activities employing one-neutron transfer reactions [1–4], traditional β-decay studies are an attractive technique to refine our knowledge on 133Sn. Since the positions of neutron single-particle states in 133Sn were established and confirmed in many measurements [1–5], our focus moves to single-hole states expected at higher excitation energies. Because of the low neutron-separation energy of 133Sn, Sn=2.4 MeV [6], all of them are supposed to be neutron-unbound. β-decay studies are therefore a natural choice to investigate their nature since there is a large energy window for their population in the β decay of 133In (Q_β =13.4(2) MeV [6]). Our experiment was performed at the ISOLDE Decay Station, where excited states in 133Sn were investigated via the β decay of 133In. Isomer-selective ionization using the ISOLDE RILIS enabled the β decays of 133gIn (Iπ =9/2+) and 133mIn (Iπ=1/2−) to be studied independently for the first time. Thanks to the large spin difference of those two β-decaying states, it is possible to investigate separately the lower- and higher-spin states in the daughter 133Sn and thus to probe independently different single-particle and single-hole levels. We identified new γ transitions following the 133In→133Sn decay. Single-hole states in 133Sn were found at energies exceeding S_n up to 3.7 MeV [7]. Due to centrifugal barrier hindering the neutron from leaving the nucleus, the contribution of electromagnetic decay of those unbound states was found to be significant. [1] K. L. Jones et al., Nature (London) 465, 454 (2010). [2] K. L. Jones et al., Phys. Rev. C 84, 034601 (2011). [3] J. M. Allmond et al., Phys. Rev. Lett. 112, 172701 (2014). [4] V. Vaquero et al., Phys. Rev. Lett. 118, 202502 (2017). [5] P. Hoff et al., Phys. Rev. Lett. 77, 1020 (1996). [6] M. Wang et al., Chin. Phys. C 41, 030003 (2017). [7] M. Piersa et al., Phys. Rev. C 99, 024304 (2019).

Speaker: Ms Monika Piersa (Faculty of Physics University of Warsaw)

113 Development and testing of a neutron radiation spectrometer in the fields of radionuclide sources

The personal dosimetry of neutron exposure is one of the most difficult problems at workplaces. Behind the biological protection of nuclear physics facilities neutron radiation has continuous spectrum, spanning up to 11 orders in magnitude – from thermal up to several GeV. It is necessary the energy response function of personal dosimeter has to be as close as possible to the appropriate fluence-to-personal dose equivalent conversion function (Hp(10)) to provide adequate value of effective dose estimation. Due to there are no personal dosimeters with appropriate energy response function, readings of current personal dosimeters radically differ from the actual values of the neutron effective dose. Nevertheless, there are some approaches to solve this problem. The easiest way to achieve adequate value of effective dose estimation is using of a correction factor to a personal dosimeter reading, which is calculated using the known dosimeter response function and the energy spectrum of the operational field. To obtain information about operational neutron spectrum it is possible to use Bonner sphere spectrometer. Development and testing of one of such spectrometers are presented in this work. The detector system consists of active neutron detector based on He-3 and a set of the 12 polyethylene sphere-moderators with diameters from 3” up to 12”. Spectrometer was exposed in fields of 238Pu(α,n)Be and 252Cf radionuclide sources. Well-known mathematical technique of integral equations solving was used to spectrum unfolding (deconvolution).

Speaker: Mariia Pyshkina (IIE UB RAS)

114 Detailed study of No and Rf isotopes radioactive decay properties.

More than 20 years experiments to synthesis and study of super heavy elements radioactive decay property are carried out in the Laboratory of Nuclear Reactions. Basically complete fusion reactions of 48Ca accelerated beam with targets heavier than Uranium are used. Isotopes of super heavy elements (SHE) are synthesized in the complete fusion reaction of heavy ions with target nuclei followed by neutron evaporation from exciting compound nucleus. Complete fusion reaction with neutron evaporation can be used for synthesis of limited SHE isotopes number. It is premised on presence of limited number of transuranium isotope elements which are used as a target. The detailed study experiments of Rf and No radioactive decay properties were carried out on cyclotron U400 FLNR JINR 2018-2019 years. 256Rf was studied in the complete fusion reactions 50Ti +207 Pb → 257 Rf* and 50Ti + 208 Pb → 258 Rf*. The half-life times by spontaneous fission and alpha-decay were determined and decay modes probabilities were specified (bα = 0.0029 bSF = 0.9971) in a good agreement with existing data [1][2]. 254No, 252No and 250No isotopes were synthesized in the complete fusion reactions 48Ca+208Pb→256No*, 48Ca+206Pb→254No* and 48Ca+204Pb→252No* respectively. These isotopes were studied for isomer stations. 1. F.P. Hessberger et. al.,//Spontaneous fission and alpha-decay properties of neutron deficient isotopes 257-253104 and 258106// Z. Phys. A 359, 415-425 (1997). 2. A.I. Svirikhin, A.V. Yeremin, I.N. Izosimov et. all., // Spontaneous Fission of 256 Rf, New Data// Physics of Particles and Nuclei Letters. 2016. V. 13. № 4. P. 480-482.

Speaker: Mrs Mereigul Tezekbayeva (FLNP, JINR)

115 The separation time and the total efficiency measurements of complete fusion reactions products at MASHA

The mass-spectrometer MASHA designed for determination of the masses of superheavy elements. The system separates complete fusion reaction products induced by heavy ion beams. The polygraphene foil is used as a hot absorber of the reaction products. The results of a total efficiency and a separation time measurement of short-lived mercury and radon isotopes are presented. The total efficiency measurement as a function of time was carried out at the intense heavy ion beams (up to 0,5 pA). It means that a decrease of the total separation efficiency is due to sintering (thermal destruction) of the hot absorber structure. A new hot catcher design is proposed based on thin sheet made of carbon nanotubes and graphene. The test experiments showed a good potential of using such materials for the reactions studied.

Speaker: Ms Meruyert Mamatova (JINR)

116 SIMULAION OF PRECISE EXPERIMENT OF LOSS COEFFICIENT MEASUREMENT AT DIFFERENT UCN VELOCITIES USING GRAVITATIONAL SPECTROSCOPY.

Very low energy neutrons (≈〖10〗^(-7) eV) called ultracold neutrons have a unique property – they can be stored in material or magnetic traps [1]. This gives a new opportunity to carry out experiments to study fundamental physics issues. Most of UCN experiments are statistically limited. And we are today at a point at which fundemantal physics application require larger UCN intensities in order to further advance. But nowadays the intensities of UCN that we have are not enough and require further advance. Thus, most of researches centres are working on increasing of existing UCN sources or on building new intense sources of UCN to develop experiments of neutron measurement and to improve their accuracy. Various developments have allowed one to increase the intensity of UCN considerably over the years. One of them is work, which was provided by FLNP JINR physicists [2]. One of the important parts of this work is storage vessel of UCN, which has to store maximum number of UCN. Consequently, one should note that task of building a UCN production trap from a technologically convenient material with minimum loss coefficient and high optical potential. This work is devoted to simulation of precise experiment of loss coefficient measurement depending on velocities of UCN with gravitational spectroscopy and to choose optimal parameters of storage volume. The effect of various covers and materials of trap on loss coefficients preliminary was estimated.

Speaker: Kylyshbek Turlybekuly (Turlybekuly)

117 "Gamma and fast-timing spectroscopy of 85Se isotopes populated in fission"

Nuclides in the vicinity of double magicity have simple structure, possible to explain with the shell model. Then, the nuclei is described as well bounded core (built with magic number of nucleons) and walence nucleons. The excitation-energy spectrum is dominated by single particle extitations. Understading how single particle states evolve as a function of neutron (or proton) number is of the main importance. Thus, there is a great need of systematic investigation of the nuclear structure of the nuclei in the the vicinity of the double magic nuclei. In the double magic 78Ni region it was observed that proton single particle states 2p3/2 and 1f5/2 evolve as a function of neutron number and reverse in 73Cu nad 75Cu [1,2]. It is also crucial to observe neutron single particle states evolution as a function of proton number. Such investigations showed that the neutron gap between 3s1/2 and 2d5/2 orbitals reduce with decreasing Z for N = 51 isotones down to 83Ga, but the gap seems to enlarge again for 81Zn. Recognition of 85Se nuclei structure is the next step in this investigations. The experiment was performed in IPN, Orsay on LICORNE and NUBALL facility. Excited states in 85Se were populated in fission 232Th(n,f) for the first time. This work was done in Nuball 2 collaboration. Bibliography [1] Phys. Rev. C 80, 054304 (2009) [2] Phys. Rev. C 83, 014322 (2011)

Speaker: Ms Ewa Adamska (Faculty of Physics, University of Warsaw)

118 Instrumentation for synthesis of superheavy elements at SHE factory

Talk will cover instrumentation being prepared for the Dubna Gas-filled recoil separator II (GNS-2) at Superheavy elements factory (SHE factory). Talk will cover DAQ electronics of various kinds, TOF technique, spectrometer status for detection of SHE, remote control of PSUs for GNS-2 magnets. Custom electronics blocks developed by author.

Speaker: Mr Leo Schlattauer (Palacky University Olomouc, Czech Republic)

Deep and Machine Learning methods for document clustering and classification

Convener: Dr Alexej Streltsov

16:00 Coffee break

Condensed Matter Physics: Section 2 Part 2

Conveners: Dr Ivan Bobrikov (JINR), Timur Tropin (Joint Institute for Nuclear Research)

119 Peculiarities of magnetization loops forms of highly anisotropic NbTi superconducting tapes in an inclined magnetic field

At the present time the various composite superconducting wires (mainly based on conventional Nb-Ti alloy and intermetallic compound Nb3Sn, or on modern high-temperature superconductors) have application to superconducting magnetic systems. All these materials demonstrate pronounced anisotropy of current carrying capacity caused by: 1) internal physical properties of vortex matter (in HTS layered compounds there is the high anisotropy of the effective mass of carriers, values of the coherence length ξ and the magnetic field penetration length λ); 2) due to anisotropic pinning system (even in metals with cubic cell) which appears during wire drawing process and observed in practical superconductors such as Nb3Sn and Nb-Ti. In the present work we used thin superconducting Nb-Ti tapes to investigate anisotropic pinning processes. The degree of critical current anisotropy of narrow-width Nb-Ti samples can be varied by cutting from wide Nb-Ti tape at different angles to rolling direction or by high-temperature (380-450°C) aging. We used Vibrating Sample Magnetometer to measure magnetization in field up to 1 Т with different orientation of field vector to samples. Some peculiarities in magnetization loop form were registered in low-field area in inclined field. It was shown that these features can be explained in taking into account inhomogeneous current distribution over the sample cross section due to the high anisotropy of the current-carrying capacity of Nb-Ti tape and the effect of the self-field. The results are discussed in comparison with magnetization loops for HTS.

Speaker: Mr Valentin Guryev (National research centre "Kurchatov Institute")

120 Structural studies of the ancient Iranian bowl by means of the neutron radiography and tomography methods

One of the most important tasks of archeology and other history-related sciences is the comprehensive study of cultural heritage items. The results of these studies have a significant application value, because they provide a way to penetrate into the far past and allow us to understand the formation and evolution of civilizations and ethnic groups. One of the non-destructive methods is neutron radiography and tomography. The fundamental difference in the nature of neutron interactions with matter compared to X-rays provides additional benefits to neutron methods, including sensitivity to light elements, a notable difference in contrast between different metals, and high penetration ability. The non-destructive character of the neutron radiography and tomography method has prompted the rising interest in studying rare archaeological items and museum rarities, especially metallic artifacts, weapons and ancient jewelry. My talk presents the visual 3D structural volume data of the studied cultural heritage object, as well as the results of the corresponding analysis. The attenuation of the neutron beam corresponds to the scattering and absorption losses inside the matter. The neutron attenuation coefficients for a neutron beam of a glue material are larger in comparison to the relevant parameters for the glass. Due to this fact, it is quite easy to recover the hidden glue tracks in the glass bowl. Morphological calculations based on the experimental tomography data were used to analyze the spatial arrangement of different components of the studied bowl.

Speaker: Mr Evgenii Kolupaev (MSU, JINR)

121 Study of the local atomic structure of silver ions in silicate glasses based on X-ray absorption spectroscopy and computer modeling by using density functional theory.

Noble metal nanoparticles are of great interest for a wide range of disciplines due to their unique optical properties. In particular, silver nanoparticles exhibit strong light absorption in the UV range. This phenomenon arises due to the plasmon resonance effect, which can be configured by changing the synthesis technology. To predict the properties of the final product one has to understand the mechanisms which are responsible for forming this product. Despite the fact that the growth process of silver nanoparticles is being actively investigated, we have to pay additional attention to the fixing process of silver ions in glass and the formation of initial stable structures. One of the possible mechanisms for the fixing of silver ions can be so-called hole traps centers. Their study is hampered by the amorphous glass structure. In this work we propose an approach to determining the local atomic structure of silver ions in glass matrices with the help of computer modeling by using density functional theory methods which are supported by X-ray absorption spectroscopy. To get the initial parameters we will use the EXAFS analysis and then we will verify our results by comparing the calculated XANES spectra with the experimental data. Research performed by support of grant RFFR 18-32-00818 mol_a

Speaker: Mr Veniamin Durymanov (Aleksandrovich)

122 Influence of preparation conditions on the electrochemical properties of layered cathodes for lithium-ion batteries

Most of the layered cathode materials for lithium-ion batteries (for example LiNi0.8Co0.2O2, LiCo1/3Ni1/3Mn1/3O2, LiNi0.8Co0.15Al0.05O2, LiNi0.5Mn0.5O2, LiNi0.95Fe0.05O2 and etc) show abnormal phase separation during the first charge instead of solid solution behavior [1]. Among them, LixNi0.8Co0.15Al0.05O2 (NCA) is one of the most common cathode materials for Li-ion batteries. It has a high practical specific capacity (~200 mA∙h/g) and exhibits a good cyclability at room temperature. The abnormal phase-separated state in this compound disappears completely during the first discharge and it is never observed in the following charge-discharge cycles. There is a possibility the abnormal state in layered cathode material depends on preparation conditions. Thus in our previous work [1], it was established that stronger compaction of the electrodes partially suppresses the phase separation of the NCA cathode material. The observed correlations made it possible to suggest that the widespread morphology of layered cathode materials (10-20 μm framboid-like secondary particles which consist of 0.5-1 μm primary particles) affects the phase separation of NCA. In the present work, this assumption has been verified. X-ray diffraction was used for new investigations of the phase-separated state of NCA. In addition to the compaction degree, parameters such as grinding of the cathode material and the amount of binder were changed. The electrode preparation procedure was developed, which allows obtaining only primary particles of the cathode material in the battery electrodes and uniform distribution of the components (NCA, carbon black and binder). It was shown the grinding of the cathode material fully changes abnormal phase separated state to solid solution state in NCA during the first cycle. The observation for NCA could be expanded to layered cathode materials with similar morphology. [1] Bobrikov I.A., Samoylova N.Yu., Ivanshina O.Yu., Vasin R.N., Sumnikov S.V., Kornieieva K.A., Balagurov A.M. Abnormal phase-separated state of LixNi0.8Co0.15Al0.05O2 in the first charge: effect of electrode compaction. // Electrochimica Acta (2018) 265 PP. 726-735.

Speaker: Dr Olga Ivanshina (JINR)

123 A combined approach for solid electrolytes investigations: handling geometrical/topological screening datasets

Search for potential conducting materials with promising electrochemical properties is of increasing interest due to electronic gadgets of all kinds and modern electric vehicles demand reliable, robust and safe storage devices of electrochemical energy. Both theoretical [1] and experimental [2] ways are possible, nevertheless computer modelling is a powerful tool for high-throughput searching of conducting/intercalating materials that meet the requirements of safety, durability and cost. One of the existing methods for fast screening of the the crystal structure databases is based on Voronoi-partition approach and is implemented in the ToposPro program package [3]. By now, it was applied for searching for the promising (from the geometrical/structural point of view) lithium [4], sodium [1], potassium [5] solid electrolytes. Amount of the structures (several hundred structures or less) in the obtained datasets is much lower than the initial set of structures. However, the subsequent investigation of the proposed materials within the precise quantum chemical methods is still complicated by their computational complexity. On of the possible solutions is to apply bond valence landscape approach [1]. Another approach that is being developed currently rests upon topological analysis of model electron density distributions for the big sets of promising solid electrolytes. The main idea of the proposed approach is to find correlations between topological properties of the electron density distribution calculated using the procrystal method with the DFT-modelled migration barriers in tested compounds. The proposed approach can be used for making an initial guess for nudged elastic band method on the ion trajectory in the crystal field individually or in a combination with the existing approaches. Present report summarizes the current results obtained for different sample sets of crystal structures, obtained by screening of Inorganic Crystal Structure Database. The authors thank hardware and software facilities of the ‘Zeolite’ supercomputer at the Samara Center for Theoretical Materials Science and the ‘HybriLIT’ heterogeneous platform at the Laboratory of Information Technologies of the Joint Institute for Nuclear Researches (Dubna, Russia). The study was funded by Ministry of Science and Higher Education of the Russian Federation (project No.3.6588.2017/9.10) and Russian Foundation for Basic Researches (project No.18-33-00477). [1] Meutzner, F., Münchgesang, W., Kabanova, N. A., Zschornak, M., Leisegang, T., Blatov, V. A., & Meyer, D. C. (2015). On the Way to New Possible Na‐Ion Conductors: The Voronoi–Dirichlet Approach, Data Mining and Symmetry Considerations in Ternary Na Oxides. Chemistry–A European Journal, 21(46), 16601-16608. [2] Yan, G., Mariyappan, S., Rousse, G., Jacquet, Q., Deschamps, M., David, R., Tarascon, J. M. (2019). Higher energy and safer sodium ion batteries via an electrochemically made disordered Na3V2PO4)2F3 material. Nature communications, 10(1), 585. [3] V.A. Blatov, A.P. Shevchenko, D.M. Proserpio, Applied Topological Analysis of Crystal Structures with the Program Package ToposPro, Cryst. Growth Des. 14 (2014) 3576–3586 [4] N.A. Anurova, V.A. Blatov, G.D. Ilyushin, O.A. Blatova, A.K. Ivanov-Schitz, L.N. Dem’yanets, Migration maps of Li+ cations in oxygen-containing compounds, Solid State Ionics. 179 (2008) 2248-2254. [5] R.A. Eremin, N.A. Kabanova, Y.A. Morkhova, A.A. Golov, V.A. Blatov, High-throughput search for potential potassium ion conductors: A combination of geometrical-topological and density functional theory approaches, Solid State Ionics. 326 (2018) 188–199.

Speaker: Dr Pavel Zolotarev (SCTMS)

124 Synthesis and temperature changes of the properties of magnetite nanoparticles

In recent decades, the study of metal nanoparticles is one of the leading areas of materials science. Particular attention is caused by magnetite nanoparticles (Fe3O4), which have a number of promising properties that distinguish them from macromaterials, which allows them to be used in nanomedicine for targeted drug delivery, visualization of objects and tissues in vivo in vitro by MRI, cancer treatment, and malignant hyperthermia , as well as in electric batteries [1]. Magnetite nanoparticles are used for the pharmacocorrection of anemic conditions, since iron is part of the blood [2]. This paper presents the results of the synthesis of thermal annealing of magnetite nanoparticles. The results obtained showed that an increase in the annealing temperature leads to a change in the mass and elemental composition of the synthesized nanoparticles. According to the data of energy dispersion analysis, at the processing temperature of 400-500 ° C, the iron content in the samples increases, followed by a sharp drop in the iron concentration and an increase in the oxygen concentration, which indicates phase and structural transformations of the nanoparticles in the annealing process.

Speaker: Mrs Kamila Yegizbek (Bakhtzhankyzy)

125 Modeling of Copper Nanoclusters Interaction with Metals at Energies of 100 eV - 10 keV

In this work, the molecular dynamics method was used to study the processes of interaction of copper nanoclusters by energies in the range of 100 eV - 10 keV with metal targets of various sizes. The results of the formation of shock waves depending on energy of a nanocluster and the size of a target are obtained. The effects of shock waves were also investigated to explain the effect of long-range action. Classification of the arising structural changes in target depth depending on energy of a nanocluster and the size of a target is carried out. The obtained results show the action of shock waves by one of the possible mechanisms for the formation of a long-range effect.

Speaker: Zafar Tukhliev (JOINT INSTITUTE FOR NUCLEAR RESEARCH)

High energy physics: Theory

Conveners: Dr Alexey Aparin (Joint Institute for Nuclear Research), Oleg Samoylov (JINR)

126 Cross-checks for the particle-identification algorithm in nue analysis by the means of muon removal procedure at the NOvA experiment

Neural networks become a wide-spread way to identify particles in the high energy experiments and neutrino physics follows this tendency. Primarily goal of the NOvA experiment is neutrino oscillation studies which require good identification for the nue and numu interactions. For this purpose, NOvA developed a convolutional neural network based particle identification algorithm CVN. We check the selection efficiency of this procedure in nue analysis with muon removal algorithm. By creating a control sample of “electron neutrino” events we can monitor any possible differences in the data and Monte-Carlo behavior.
 This talk will be devoted to the description of this procedure for NOvA’s nue analysis.

Speaker: Ms Liudmila Kolupaeva (JINR)

127 Cross channel Radon tomography

We review crossed channel Radon tomography of generalized parton distributions (GPD). We present a procedure to derive separate channel contributions to double distributions (DD) via limited angle inverse Radon transform (RT). The LO photon GPDs has been considered as a clear analytical test. Recently the pressure distribution inside proton has been derived where besides negative sign of the D-term has been found which in accordance with hadron mechanical stability criteria on energy momentum formfactor. We show that photon fulfills necessary stability criterion as well.

Speaker: Mr Ilnur Gabdrakhmanov (JINR VBLHEP)

128 Correlation observables in ΥD pair production at the LHC within the parton Reggeization approach

We study angular correlations in associated hadroproduction of Υ(1S) with the D± and D0 mesons at the LHC in the Leading Order of the parton Reggeization approach. This approach is based on the kT-factorisation and the gauge-ivariant effective field theory of L. N. Lipatov. Hadronization of a $\bar{b}b$-pair to Υ(1S) is described within the NRQCD-factorization framework. Production of D−mesons is described in the fragmentation model with scale-dependent fragmentaion functions. We have found good agreement with LHCb data for various differential distributions, except for the case of spectra on azimuthal angle differences at the small values. The total cross-section in our Single Parton Scattering model, calculated under conservative assumptions, accounts for almost one half of observed cross-section, thus dramatically shrinking the room for Double Parton Scattering mechanism.

Speaker: Mr Anton Karpishkov (Samara National Research University)

129 MEASUREMENT OF THE VECTOR AND TENSOR ANALYSING POWERS FOR DP-ELASTIC SCATTERING AT THE ENERGY OF 800 MeV

The vector Ay and tensor analyzing powers Ayy and Axx for dp-elastic scattering were measured at the energy of 800 MeV and in the angular range from 60° to 140° in the center-of-mass system at the JINR Nuclotron. The experimental data are compared with the calculations obtained within framework of relativistic multiple scattering approach.

Speaker: Mrs Olena Mezhenska (P. J. Šafárik University in Kosice)

130 Decay $B_s\to K^{*0} \mu^+ \mu^-$ in covariant quark model

TBA

Speaker: Dr Aidos Issadykov (Jinr)

Slides Issadykov_AYSS2019.pptx

131 Pion production in the 84Kr-Emulsion interactions at around 1GeV/n

Relativistic nucleus-nucleus (A-A) and hadrons - nucleus (h-A) collisions are very useful to understand the particle production mechanism. The present work is devoted to the investigation on emitted charged pions from 84Kr36 - Emulsion interaction at 1 GeV/n. Here we have calculated the total number of wounded nucleons (W) and the total number of interactions (ν) using wounded nucleon model. The obtained results revealed that the estimated number of wounded nucleons and the total number of interactions are strongly dependent on the mass number of the colliding nuclei. We have also observed that the mean multiplicity of pions increases with increasing the total number of wounded nucleons and the total number of interactions.

Speaker: Mr N MARI MUTHU (Banaras Hindu University)

Nuclear Physics: Section 1

Conveners: Dr Dmitry Testov (JINR), Mrs Yulia parfenova (Joint Institute for Nuclear Research)

132 Measurements of ambient thermal neutrons with modern lithium containing scintillation detectors

For all stages of low-background experiments starting from concept of the shields, modeling as well during the operation comprehensive knowledge of gamma and neutron ambient backgrounds at the experimental sites is between of the most important tasks. Many various types of detectors are usually applied for experimental studies and monitoring of these backgrounds. In general completely different detectors serve for neutron and a gamma-ray measurements. Each of the detectors is required own acquisition chain, data analysis and a place for installation which is always limited in tighten conditions of low background underground laboratories. Therefore, for optimization of experiments the use of a detector, which can measure both the neutron and gamma background simultaneously, is very promising. One of these detectors are lithium-6 containing scintillators. Some of the modern types of such detectors are inorganic crystals CLYC (Cs2LiYCl6: Ce) and CLLB (Cs2LiLaBr6: Ce). Detectors based on these scintillators have a high energy resolution on gamma lines (~ 4% FWHM on Cs-137 662 keV line), moreover such detectors provide the separation of neutrons and gammas by pulse shape discrimination (PSD). This work presents first measurements of ambient neutron and gamma backgrounds performed in JINR with these detectors. Detectors' response (energy resolution and stability, efficiency, PSD capability, etc), to gamma and neutrons has been determined. Own gamma background of the detectors and their contamination by alpha isotopes in neutron detection region was investigated. Thus, the possibility of using such detectors in low-background experiments with low neutron flux was evaluated.

Speaker: Mr Dmitriy Ponomarev (engineer)

133 A new in-flight fragment separator Acculinna-2 at the U-400M cyclotron in FLNR for experimental evidence of unbound 7H

RIBs (Radioactive Ion Beams) research is an important direction in modern Nuclear Physics to provide full coverage of the nuclear chart for nuclear-stable isotopes and to promote our knowledge to the limits of nuclear structure existence. The information obtained in the RIB studies is indispensable to resolve fundamental problems of nuclear physics (structure, reactions, origins of the nuclear forces) and nuclear astrophysics (nucleosynthesis, properties of the neutron matter). How do protons and neutrons make stable nuclei and rare isotopes? What are properties of neutron matter? What are the heaviest nuclei that can exist? The nuclear structure and reaction mechanisms are being done more than ever, radioactive isotope beams brought the discovery of new forms of nuclei such as the neutron halo and neutron skin by using an in-flight method with a magnetic spectrometer, which leads a wide range of radioactive nuclei is produced as projectile fragments. ACCULINNA-2 is a part of Dubna Radioactive Ion Beam (DRIBs) project. It is a new in-flight facility at the U-400M cyclotron developed for studies of exotic nuclear systems with atomic number Z<20. At ACCULINNA-2, the use of secondary beams of radioactive nuclei considerably widens the possibilities to investigate the properties of atomic nuclei and nuclear reactions: investigation of the properties of atomic nuclei far from the stability line, including nuclei at the neutron drip-line, study of the peculiarities of the dynamics of nuclear reactions induced by neutron-rich nuclei, synthesis and study of the properties of new elements and isotopes. The new facility fragment separator ACCULINNA-2 was put into operation at the beginning of 2015 in FLNR, JINR. The new separator is applicable to study of the structure of light unstable nuclei and resonant reactions for astrophysical studies. The 8He secondary beam was successfully produced with a high intensity of 10 4 particle per second and a purity of 87% at 26 MeV/amu by using the in-flight method for experimental evidence to observe the resonance state of unbound nuclei 7H.

Speaker: Ms Anh Mai (Joint Institute for Nuclear Research)

134 Study of interaction of charged light particles with 1p shell nuclei

The work is devoted to experimental and theoretical study of charged light particles elastic and inelastic scattering processes from 9Be,11B and 12C nuclei by measuring differential cross sections of these processes and their further analysis.

Speaker: Dr Daniyar Janseitov (BLTP/INP)

Deep and Machine Learning methods for document clustering and classification

Convener: Dr Alexej Streltsov

Thursday 18 April

Plenary session: Prof. Kisiel Adam "Towards realisation of the MPD project"

Convener: Dr Alexey Aparin (Joint Institute for Nuclear Research)

11:00 Coffee break

Plenary session: Dr. Chudoba Vratislav "Exotic nuclei in everyday life"

Convener: Dr Alexey Aparin (Joint Institute for Nuclear Research)

12:30 Lunch

High energy physics: Section 2 Part 1

Conveners: Dr Alexey Aparin (Joint Institute for Nuclear Research), Mr Vadim Babkin (Joint Institute for Nuclear Research)

135 Prototype of light collection module for LAr TPC (ArgonCube).

Light collection module (LCM) is intended for registration a vacuum ultraviolet light in a liquid argon time projection chamber. The core of the LCM is a WLS-fiber array, coated by TPB solution, which is fixed on a PVC plate. LCM is being developed and made as a part of a light registration system of ArgonCube in Dzelepov Laboratory of nuclear problems at JINR. ArgonCube is a modular pixilated LAr TPC, which is being developed for it possible usage as a near detector of the Deep Underground Neutrino Experiment (DUNE).

Speaker: Alexey Chetverikov (LNP)

136 The cross section of the inelastic interaction of protons and helium nuclei with the tungsten obtained with the PAMELA space experiment

We present the energy dependence of the cross section for the inelastic interaction of protons and helium nuclei with the tungsten in the energy range from a few hundred MeV to a hundred GeV using the data of the PAMELA space experiment. It was intended for the precision measurements of the cosmic ray fluxes of different nature and include a set of detectors for the reliable determination of the particle characteristics (their type and energy). Identification of particles was carried out with the tracker system in magnetic field, time-of-flight and anticoincidence systems. A coordinate-sensitive calorimeter with a tungsten absorber, in turn, allows us to study the topology of the interaction of particles inside it, and calculate the cross-section of their inelastic interaction. We present the comparison of the obtained results with the measurements at accelerators and with existing theoretical models. The results of the work can be demanded for the development of numerical models describing particle’s interactions.

Speaker: Ms Olga Golub (NRNU MEPHi)

137 Stand to test preamplifiers of SiPM signals for electromagnetic calorimeter of the MU2E experiment.

In this work a stand to test preamplifiers for electromagnetic calorimeter of the MU2E experiment (Tevatron, Fermilab) is presented. For this stand the control board has been developed, assembled and tested. Methods to test preamplifiers are proposed. A software for stand is being debugged.

Speaker: Mr Ilya Moroz (JINR, TGU)

138 Studies of the 16- channel scintillation detector prototype with SIPM readout.

Modern silicon photomultipliers are widely used in detectors of a wide class of experiments CERN, FAIR and NICA/Nuclotron. One example of their application is electromagnetic and hadron calorimeters. In the Laboratory of high energy physics, 16-channel prototypes of detectors (with SIPM readout from Ketek, Sensl and Hamamatsu) were developed which can be used both in Zero Degree calorimetry and for measuring the profile of a low-energy neutron beam. The paper presents the measurement of the noise characteristics of the detectors in the temperature range from 27.7 °C to 39.1 °C and the study of the response from the light source (LED) at different voltages. The correlation of the breakpoint of the noise characteristic with the breakdown voltage in the silicon photomultiplier was revealed. The prototype based on the Ketek SiPM was tested at the deuteron beam of the JINR Nuclotron at an energy of 4 GeV/nucleon. The time resolution and amplitude of the signal were estimated.

Speaker: Mr Aleksey Tishevskiy (VBLHEP,JINR)

139 Application of the Prony least squares method for fitting signal waveforms measured by sampling ADC

At present, new forward hadron lead/scintillator sampling calorimeters are constructed for the Compressed Baryonic Matter (CBM) experiment at the future Facility for Antiproton and Ion Research (FAIR) and the Multi Purpose Detector (MPD) at Nuclotron-based Ion Collider Facility (NICA). These calorimeters will be used for centrality and the reaction plane orientation measurements in heavy-ion collisions. A wide dynamic range requires reliable determination of the scintillation signal parameters. Digitizing of an analog signal with sampling ADC results in strong fluctuation of the measured charge. To improve the response, the new procedure of fitting signals based on the Prony least squares method has been proposed. This method represents waveform as a linear combination of exponential functions and allows to obtain the charge more accurately. Moreover, fitting the waveforms with the Prony method requires minimum machine time. The procedure of fitting the waveforms of calorimeter signals using the Prony least squares method will be presented. The application of this method will be shown for the processing of signals, obtained in hadron calorimeter tests on cosmic muons and on hadron beams at CERN using sampling ADC board ADC64s2 (AFI Elecronics, Dubna). It will be shown that fitting of the signals with a known function allows to isolate weak signals comparable to the level of electronic noise, which is important for performing a muon calibration of calorimeter sections.

Speaker: Mr Nikolay Karpushkin (Institute for Nuclear Research of the Russian Academy of Sciences)

Slides karpushkin_AYSS.pdf

140 Performance of the ALICE charged-particle veto detector in PbPb and pp collisions at LHC

The charged-particle veto (CPV) detector of the ALICE experiment is a multi-wire proportional chamber with pad readout. It is designed to improve photon identification in the photon spectrometer PHOS. One module of the CPV detector was put in operation during LHC Run2 in 2015. In this talk we will present the performance of the CPV during PbPb collisions at \sqrt{s}=5.02 TeV and compare these to the previously obtained results for pp collisions at \sqrt{s}=13 TeV. We will discuss the efficiency of charged-particle track reconstruction in the CPV and photon identification in the ALICE photon spectrometer using the CPV detector both in pp and Pb-Pb collisions.

Speaker: Mr Evgeny Kondratyuk (IHEP)

Slides kondratyuk_ayss_18.04.2019.pdf

141 Multi-channel pulse counter based on the Altera field programmable gate array

Currently active work on preparation of JUNO reactor neutrino experiment in China is underway. The primary goal of the experiment is the determination of neutrino mass hierarchy. Alongside with that the precision of some other neutrino mixing parameters can be improved. In order to reach these ambitious goals the detector of the experiment is supposed to have unprecedented resolution on the incident particles energy (3%/MeV). It places high demands on the photomultiplier tubes (PMT) efficiency and the properties of the scintillator. PMTs are being thouroughly examined and tested. They must have high degree of uniformity of gain and photon detection efficiency along the photocathode surface. Besides that this experiment is supposed to be ongoing at least for twenty years after its beginning. When the experiment starts there will be no possibility to replace non-working PMTs. Concerning this the long-term PMT stability tests come to play. Multi-channel pulse counters are required to carry out such tests. The operation of such counters will be implemented on the basis of Intel (Altera) field programmable gate arrays. The report will describe the schematic diagram of the device as well as the implementation of basic functional units by means of Verilog hardware description language.

Speaker: Mr Ilya Butorov (JINR)

142 Study of the BM@N GEM/CSC tracking system performance

BM@N (Baryonic Matter at the Nuclotron) is the fixed target experiment aimed to study nuclear matter in the relativistic heavy ion collisions at the Nuclotron accelerator in JINR. Detectors based on Gas Electron multipliers (GEM) have been identified as appropriate for the BM@N central tracking system, which is located inside the BM@N analyzing magnet. Cathode Strip Chamber (CSC) is installed outside the magnet to improve momentum resolution of the experimental setup. The structure of the GEM and CSC detectors and the results of study of their characteristics are presented.Both GEM and CSC detectors are integrated into the BM@N experimental setup and data acquisition system. Their performance at the last Nuclotron run is shortly reviewed.

Speaker: Mr Andrei Galavanov (JINR, MEPhI)

Slides Galavanov_AYSS_2019.pdf

Information Technologies: Part 1

Conveners: Mr Igor Pelevanyuk (JINR), Dr Olga Derenovskaya (LIT JINR)

143 Kotlin language for science and kmath library

Kotlin is a new but astonishingly fast developing general purpose language. It already conquered android and currently fighting for web back-end market. The important part is that being "better Java", Kotlin has a potential to be a good language for scientific purposes. Especially with arrival of multi-platform compilation and support of JavaScript and native targets. In this talk I would like to describe the advantages (and some disadvantages) of kotlin language for scientific purposes. And present a kmath library for multiplatform mathematics in kotlin, which utilizes unique kotlin context-oriented features.

Speaker: Dr Alexander Nozik (INR RAS, MIPT)

Slides AYSS-2019.pptx

144 Govorun supercomputer engineering infrastructure . Monitoring system of engineering infrastructure.

A complex engineering infrastructure has been developed to support Govorun supercomputer that is expansion of the HybriLIT heterogeneous cluster. This infrastructure combines integration of two solutions on cooling systems: air cooling system for the GPU-component and water cooling system for the CPU-component based on the solution of the RSC Group. The report provides a review of the engineering infrastructure of the supercomputer, and it is important to note that a special emphasis is put on the water cooling system. Review on the monitoring system based on the solution of the "RSC BazIS" which allows managing both separate nodes and all nodes of the infrastructure component will be also presented in the report.

Speaker: Alexey Vorontsov (LIT, JINR)

145 Monitoring system development for the GOVORUN supercomputer

The GOVORUN ssupercomputer is designed for the development of parallel applications and for carrying out parallel computations required by a wide range of tasks in JINR. To increase the efficiency of the GOVORUN supercomputer, the following should be done: a) supercomputer’s accounting system - helps supervisors and system administrators evaluate performance of the supercomputer; b) nodes utilization and services monitoring system- helps users to optimize usage of the supercomputer nodes and improve their own code; c) monitoring of servers – notifies system administrators about failure statistics; d) engineering infrastructure monitoring system – notifies system engineers about failures.

Speaker: Ivan Kashunin (JINR)

146 IT-environment of the HybriLIT platform

To be done

Speaker: Ms Shushanik Torosyan (LIT)

147 Remote desktop configuration fo rwork with high performance graphical applications

TBD

Speaker: Mikhail Matveyev (JINR)

148 Software environment for computing of NICA megaproject

To be done

Speaker: Mr Maxim Zuev (JINR)

Slides 2019_ayss.pdf

149 Particle track reconstruction with the TrackNETv2

Modern high-energy physical detectors provide a huge amount of data, and for future high-luminosity colliders such as NICA, an Exabyte data scale is expected. Particle track reconstruction in such a dense environment is a very challenging task. Common algorithms make use of hand-engineered features and do not scale well with detector occupancy. This work is a logical continuation of the research presented on the XXII International Scientific Conference of Young Scientists and Specialists (AYSS-2018), where we have already introduced the approach of sequential tracking with the help of ad-hoc deep recurrent neural network named TrackNET. But that first version had a number of problems. To address these shortcomings, we introduce here the TrackNETv2, which is faster, has much fewer parameters and is able to train directly from Monte-Carlo simulated events.

Speaker: Mr Pavel Goncharov (Sukhoi State Technical University of Gomel, Gomel, Belarus)

Slides P._Goncharov.pdf

150 Graph neural network application to the particle track reconstruction for data from the GEM detector

Tracking particles is a challenging problem in modern high-energy physics detectors producing a vast amount of data, such as experiments on the future NICA collider. Particle track reconstruction is one of the important parts of such experiments, but existing tracking algorithms do not scale well with a growing data stream. In the same time, new effective tracking methods based on graph neural network (GNN) are actively developed and tested in the HEP.TrkX project at CERN. We introduce our GNN approach for the GEM detector of BM@N experiment of the NICA megaproject. Our approach is well-adapted for solving the known fake hit problem inherent to strip detectors like GEM. Preliminary results are presented.

Speaker: Mr Egor Shchavelev (Saint Petersburg State University)

Slides e_shchavelev.pdf

Nuclear Physics: Theory

Conveners: Dr Alexey Severyukhin (BLTP, JINR), Dr Nikolay Arsenyev (Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research)

151 Analytical description of shape transition in nuclear alternating parity bands

Angular momentum dependencies of the parity splitting and electric dipole transitions in the alternating parity bands of heavy nuclei have been analyzed. It is shown that these dependencies can be treated in a universal way with a single parameter of critical angular momentum, which characterizes phase transition from octupole vibrations to the stable octupole deformation. Using the simple but useful model of axially-symmetric reflection-asymmetric mode, the analytical expression for the parity splitting and electric dipole transitional moment have been obtained. The results obtained are in a good agreement with the experimental data for various isotopes of Ra, Th, U, and Pu.

Speaker: Evgenii Mardyban (Vasilevich)

152 Pauli-principle driven correlations in four-neutron nuclear decays

Mechanism of simultaneous non-sequential four-neutron (4n) emission (or ``true'' 4n-decay) has been considered in phenomenological five-body approach. This approach is analogous to the model of the direct decay to the continuum often applied to 2n- and 2p-decays. It is demonstrated that 4n-decay fragments should have specific energy and angular correlations reflecting strong spatial correlations of ``valence'' nucleons orbiting in their 4n-precursors. Due to the Pauli exclusion principle, the valence neutrons are pushed to the symmetry-allowed configurations in the 4n-precursor structure, which causes a ``Pauli focusing'' effect. Prospects of the observation of the Pauli focusing have been considered for the $4n$-precursor \isotope[7]{H} Fingerprints of it nuclear structure or/and decay dynamics are predicted.

Speaker: Mr Pavel Sharov (JINR)

153 Beta-decay and electron capture rates of hot nuclei in stellar matter

Thermal effects on the electron capture and beta-decays rates are studied for 56Ni embedded in dense and hot matter of the collapsing core of a massive star. The influence of temperature on the strength distributions of GT transitions is considered in the framework of the Skyrme-TQRPA model. It is shown that thermal effects make possible negative- and low-energy GT transitions which are Pauli blocked at zero temperature. The obtained weak-interaction rates are compared with those from the large-scale shell model calculations.

Speaker: Mr Semyon Sidorov (Moscow State University named after M.V. Lomonosov)

154 Interference patterns in angular distributions observed for 10He decay products

Representing extreme nuclear matter asymmetry 10He nucleus is attracted a lot of attention. Despite a long story of trying to research this unbound system, there are still many contradictions in obtained results. Partly it is connected with a difficult recognition of broad states in the continuum. In recent experimental research, the spectrum of low-lying states in the 10He was populated in two neutron transfer reaction from tritium target (S.I. Sidorchuk et al., Phys. Rev. Lett. 108 (2012) 202502). It was investigated with full kinematics techniques allowing for correlation studies. Demonstrating prominent interference patterns, internal correlations helped establish spin/parity of states in the 10He spectrum. A proposed negative parity of the first excited state contradicts to theoretical expectations. The theoretical approach in this work was simple enough and calls for more rigorous justification (L.V. Chulkov et al., Phys. Lett. B 720 (2013) 344). We testify our statements by Monte-Carlo simulating of the decay. Based on HH formalism these simulations allow for description all range of experimental data with the one set of parameters taking into account reaction mechanism, efficiency, alignment and interference of states. This unique technique for three-body decays studies was successfully applied in the analysis of 6Be, 17Ne, 45Fe and it has no analogs in the world.

Speaker: Mrs Irina Egorova (JINR)

155 The study of Coulomb breakup of 11Be

This work is devoted to a theoretical study of the Coulomb breakup of halo nuclei in a quantum mechanical approach. Exotic nuclei are the subject of intensive experimental and theoretical research. Coulomb breakup are relevant for interpretation and planning of experiments in radioactive beams. The 11Be nucleus is regarded as a neutron halo consisting of 10Be core and one neutron. Energy levels of 11Be were calculated solving Schrodinger equation by means of numerical methods. This work is the initial stage of the work on the investigation of the breakup of halo nuclei. A detailed investigation is planned to research the breakup of the halo nucleus, using the numerical method for solving the nonstationary Schrodinger equation.

Speaker: Mr Dinara Valiolda (BLTP/KAZNU)

16:00 Cofee break

High energy physics: Section 2 Part 2

Conveners: Dr Alexey Aparin (Joint Institute for Nuclear Research), Mr Vadim Babkin (Joint Institute for Nuclear Research)

156 The synchronization modules of calorimeter for display in Event Display MPD

Studying of the extremal hot and dense matter is the most pressing challenge of modern physics. The particular interest to such environments is connecting with the chance to learn new and until the poorly studied state of matter, so-called quark-gluon plasma. Is supposed by MPD installation to use all the advantages of the accelerator with high NICA luminosity. Installation MPD consists of various detector types located around bunches collision area. This paper describes the simulation of hadron calorimeter for registration particles, flying under zero angles to the axis of colliding bunches and solving the problem of energy display, absorbed in the towers of the calorimeter.

Speaker: Ms Gaukhar Zhanabergen (JINR)

157 Study of noise characteristics of irradiated pixel detectors for the new ALICE Inner Tracking System and the NICA MPD Inner Tracking Detector

The Inner Tracking System (ITS) plays a key role in the precise determination of secondary vertices in high energy hadron collisions in A Large Ion Collider Experiment (ALICE) at the Large Hadron Collider (LHC). After the upgrade in 2020 the beam luminosity of the LHC will be increased by a factor of ten refers to Pb-Pb collisions. This will provide new opportunities of studies of rare processes in high energy hadron collisions including the formation of short-lived particles containing heavy-flavour quarks. New Monolithic Active Pixel Sensors (MAPS) will be used to meet the challenging requirements of high precision tracking of charged particles and of secondary-vertices determination. These sensors can work at high radiation doses with low noise rates and therefore could also be used for the Inner Tracking System of the new Multi-Purpose Detector (MPD) at the collider NICA (Nuclotron-based Ion Collider fAcility). Extensive studies of new sensors were conducted in the course of preparations for the upgrade. As a part of this activity, the given report presents the investigations of some main characteristics and noise performance of several irradiated MAPS sensors. These studies were performed at various temperatures using special experimental set-up equipped with a cryogenic module. The reported study was supported by RFBR, research project No. 18-02-40075 mega.

Speaker: Mr Dmitrii Nesterov (St Petersburg State University)

158 Nuclear matter effects in the pion-induced Drell-Yan process at COMPASS

Cold nuclear matter effects such as parton energy loss in nuclear matter and nuclear modification of parton distribution functions in the Drell-Yan process in πA and pA collisions have been extensively studied during the last 30 years. Various theoretical models have been proposed to explain these effects, but its full understanding is still lacking. COMPASS studies nuclear effects in Drell-Yan through cross section ratios on nuclear targets using a 190 GeV π− beam scattering on ammonia and tungsten targets. The present understanding of these effects and experimental possibilities of COMPASS in this context will be discussed.

Speaker: Mr Evgenii Mitrofanov (JINR)

159 Comparison of hadron shower data in the PAMELA experiment with Geant 4 simulations

The sampling imaging electromagnetic calorimeter of $\approx 16.3$ radiation lengths and $\approx 0.6$ nuclear interaction length designed and constructed by the PAMELA collaboration as a part of the large magnetic spectrometer PAMELA. Calorimeter consists of 44 single-sided silicon sensor planes interleaved with 22 plates of tungsten absorber (thickness of each tungsten layer $0.26$ cm). Silicon planes are composed of a $3\times 3$ matrix of silicon detectors, each segmented into 32 read-out strips with a pitch of $2.4$ mm. The orientation of the strips of two consecutive layers is orthogonal and therefore provides two-dimensional spatial information. Due to the high granularity, the development of hadronic showers can be study with a good precision. In this work a Monte Carlo simulations (based on Geant4) performed using different available models, and including detector and physics effects, compared with the experimental data obtained on the near Earth orbit. The response of the PAMELA calorimeter to hadronic showers investigated including shower radius, longitudinal and transverse shower profiles etc.

Speaker: Mr Vladislav Alekseev (Yaroslavl State University)

Slides 20190418 Alekseev Mayorov

160 Tests of modules of Forward hadron calorimeter at MPD/NICA.

At present, in Dubna, Russia a new acceleration complex NICA is being constructed. One of its two detectors and most integral parts of the collider (NICA) is a Multi-Purpose Detector (MPD). MPD experiment is intended for study of properties of dense baryonic matter. One of the most important parts of MPD is Forward Hadron Calorimeter (FHCal), whose purpose is to measure centrality and determine orientation of reaction plane of collisions. Forward Hadron Calorimeter consists of two arms: left and right, which are situated symmetrically respective the beam collision point. Both arms have module structure, consist of 44 modules. Every module has a sandwich structure of 42 pairs of lead-scintillator plates and has a total length near four nuclei interaction lengths, which correspond to NICA energies. Each module has a transversal size of 15x15 cm2, which is chosen to be bigger than transversal size of hadronic shower that propagates inside modules. FHCal needs to register particles in a wide dynamic range. Registering low energy signals is a challenging mission to accomplish. In order to minimize the noise/signal ratio every scintillator plate has a spiral WLS-fiber imbedded in spiral grooves. Fiber has a thin mirror adjacent to it at one end in order to reflect signal from it and is connected to MPPC(multi-pixel photomultiplier) in order to ensure maximum efficiency of photoelectron detection.

Speaker: Mr Alexander Strijak (INR RAS)

Slides decapitator

161 First tests of the ECAL detector at HADES experiment

HADES is a large acceptance spectrometer operating at SIS18, GSI, Germany. It is aimed at exploration of QCD phase diagram at the ion beam energies of 1-2 AGeV in the region of high hadron densities. HADES setup includes a superconducting toroidal magnet, sets of drift chambers, ring-imaging Cherenkov detector, TOF systems and a new electromagnetic calorimeter (ECAL). The application of an electromagnetic calorimeter to HADES allows to study new reaction channels as the production of neutral mesons, neutral resonances in elementary and heavy-ion reactions. An additional advantage of ECAL is the improvement of the electron-to-pion separation at large momenta. The detector is based on 978 lead glass Cherenkov modules, that are divided into 6 sectors and cover almost the full azimuthal angle. Currently only 4 sectors are assembled and installed. The rest 2 sectors will be added in the second half of 2019. Before the installation in the experimental area each module was calibrated with cosmic rays in vertical position in the Lab. For this purpose, two scintillator counters (up and down) were triggered in coincidence to select the cosmic muons passed along the module. After the installation in the experimental hall, the ECAL modules were tested again with cosmic rays using a self-trigger mode. In the end of 2018 the first ECAL beam data were collected at the test runs with Ar- and Ag-ion beams. Initial analysis of the first data from the electromagnetic calorimeter was performed. These beam data were used to adjust the signal delays of the modules, to check the HV settings and to make the preliminary amplitude calibration.

Speaker: Mr Arseniy Shabanov (INR RAS)

162 Study of RPC detector with different gas mixture compositions using HARDROC front-end ASIC

The present study includes the integration and commissioning of Resistive Plate Chambers (RPCs) detector with HARDROC front-end electronics. HARDROC is a 64 input channel ASIC that amplifies, shapes and discriminates the negative fast detector signals. This paper reports the performance of glass RPC detector under different R134a/i-C4H10/SF6 gas mixture compositions. The preamplifier gain, DAC threshold and the window size of data acquisition with respect to external trigger were optimized according to RPC signals and kept uniform during data taking in all gas compositions. The performance measures include the cosmic muon detection efficiency as well as the cluster size and count rate for the single gap RPC operated in avalanche mode. The detectors are readout by 2.8 cm X 30 cm copper strips. The number of consecutive strips or readout channels fired at the same time by the passage of charged particle as a function of electronegative SF6 gas is presented.

Speaker: Mr Aman Phogat (University of Delhi)

163 Panda Muon System Prototype

The PANDA Experiment will be one of the key experiments at the Facility for Antiproton and Ion Research (FAIR) which is under construction now in the territory of the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany. PANDA is aimed to study hadron spectroscopy and various topics of the weak and strong forces. Muon System is chosen as the most suitable technology for detecting the muons. The Prototype of the PANDA Muon System is installed on the test beam line T9 at the Proton Synchrotron (PS) at CERN. Status of the PANDA Muon System prototype is presented with few preliminary results.

Speaker: Dr Alexander Verkheev (JINR)

Slides RS.pdf

Information Technologies: Part 2

Conveners: Mr Igor Pelevanyuk (JINR), Dr Olga Derenovskaya (LIT JINR)

164 Development of the Web-service for the database of the BM@N experiment

The NICA megaproject implementing at Joint Institute for Nuclear Research (JINR) is aimed at recreating and investigating a nuclear matter under extreme conditions. One of the experiments of the NICA project is the BM@N (Baryonic Matter at Nuclotron) setup proposed to study a dense matter produced in collisions of elementary particles and heavy ions with a fixed target. To solve the task of storing information on the BM@N experiment, which is necessary for further processing of the obtained experimental data, a specialized database is under development now. For convenient user management of the data stored in the database, it is required to develop a Web-service for viewing, modifying and visualizing the information on the BM@N conducted runs. The report briefly presents the scheme of the NICA complex and the BM@N experiment. The modern development tools and libraries for implementation are shown. The developed Web-interface is described in details. Its structure and tasks to be solved (such as viewing and modifying the BM@N experiment data in tabular form, showing the summary information on the stored data and visualizing the detector geometries in the conducted sessions) is also noted.

Speaker: Mr Alexander Chebotov (JINR, LHEP)

165 Development of user interface for top tracker control software of Juno experiment

The Jiangmen Underground Neutrino Observatory (JUNO) is a multipurpose reactor neutrino experiment currently under construction in Jiangmen, China. The main physics goal of Juno is to determine the neutrino mass hierarchy by measuring the reactor antineutrino flux from two Nuclear Power Plants located in southern China. The experiment will be a record in energy resolution (3% at 1 MeV) required to achieve main goal, in the number of large photomultipliers installed (20000 20 inch PMTs) and unprecedented wide photocatode coverage (77%). The JUNO detector will consist of three main systems: a central liquid scintillation detector, ultrapure water Cherenkov veto around the central detector and a muon tracker veto which will be installed on top of of the detector. Using of two veto systems allows to reduce different sources of background more accurate. The muon tracker will use a plastic scintillator taken from the OPERA experiment currently being decommissioned. However the electronics of top tracker is developing completely separated from what was used in OPERA which requires to develop from scratch the top tracker control software. The important task is development of graphical user interface for control software. One should take into account that to achieve required energy resolution and be able distinguish neutrino mass hierarchies Juno must collect data more than 6 years. The problem of developing and creating a convenient, reliable and friendly (ergonomic) graphical interface is particularly relevant in this regard. As the basis of the graphical interface, it was decided to use the web-interface. This choice is done due to the rapid development of web technologies, as the basis for building modern interfaces, and existing solutions in this area.

Speaker: Mr Vladislav Sharov (Laboratory of nuclear problems. V. P. Dzhelepova)

166 Creating osciloscope driver with Tango Controls

Automatic control system of the NICA complex is based on Tango Controls technology. Tango possibility to create device server is illustrated on example of fast digital oscilloscope in this report.

Speaker: Mr Maxim Efimov (JINR)

167 Merging multidimensional histograms via hypercube algorithm

Scientists in high energy physics produce their output mostly in form of histograms. Set of histograms are saved in output file for each grid job. As the next step is to merge these files/histograms to one file where scientist can produce final plots for publication. Merging of these out files may be done sequentially as one job or do it in parallel via binary tree algorithm as it is done by many users. Using histogram with low dimensions (1D or 2D) one can fit in memory with final merged objects. On the other side, if dimensions or binning of histograms are increaced, sparse implementation of histogram has to be used in analysis and final object might grow so much that user will not be able to merge or open final merged object because it will not fit in memory at some point. Our task is merge these multidimensional histograms to N independed objects to multiple files, where each file will contain uniqe part of merged object sorted by some axis in histogram dimension. For optimalization reasons hypercube algorithm is used.

Speaker: Andrey Bulatov (State University Dubna, JINR)

168 Creating osciloscope GUI with Tango Controls

Automatic control system of the NICA complex is based on Tango Controls technology. Tango possibility to create client application is illustrated on example of fast digital oscilloscope in this report.

Speaker: Mr Anton Shekhovtsov (JINR)

Banquet

Friday 19 April

Plenary session: Dr. Zinicovscaia Inga "Application of neutron activation analysis in the environmental studies"

Convener: Dr Alexander Verkheev (JINR)

11:00 Coffee break

Closing

12:00 Lunch

Excursion: IBR-2

Convener: Dr Inga Zinicovscaia (Joint Institute for Nuclear Research)

Excursion: NICA

Convener: Mr Andrey Shemchuk (VBLHEP)