Measurements of the anisotropic collective flow of particles produced in relativistic heavy ion collisions play an important role in the study of the transport properties of strongly interacting matter. In this work we present the results of the most complete systematic study of the dependence of the anisotropic collective flow on the collision energy from 2.4 GeV to 5.76 TeV based on the...
Results of simulations of directed flow of various hadrons in Au+Au collisions at collision energies $\sqrt{s_{NN}}=$ 3--4.5 GeV are presented. Simulations are performed within the model three-fluid dynamics and the event simulator based on it (THESEUS). The results are compared with available data. The directed flows of various particles provide information on dynamics in various parts and...
In heavy ion collisions at the beam energy of several GeV per projectile nuclei hot and dense strongly interacting matter being produced at high baryon densities. One of the observables sensitive to the properties of this matter is the azimuthal anisotropy of the created in the collision particles. We present the results on the measured directed flow of protons and deuterons from the recent...
Long-term studies of multiparticle processes indicate an ever-increasing role of the gluon component of hadrons and its active participation in the formation of secondary hadrons. The gluon dominance model, taking into account the stage of the quark-gluon cascade, based on PT QCD and hadronization, described by a phenomenological scheme is consistent with experimental data well.
The...
M.S. Kosarev$^{1,2,3}$, N.V. Antonenko$^{1}$, N.N. Arsenyev$^{1}$, and A.P. Severyukhin$^{1,4}$
$^1$ Bogoliubov Laboratory of Theoretical Physics, Joint Institute for Nuclear Research, 141980 Dubna, Russia
$^2$ Faculty of Physics, Lomonosov Moscow State University, Moscow, 119991, Russia
$^3$ Branch of Lomonosov Moscow State University in Sarov, Sarov, 607328, Russia
$^4$ Dubna State...
The study of the pion photodecay plays an important role in particle physics. The practical interest is explained by the fact that the neutral pion decays electromagnetically in two photons with branching ratio 99%. And a great percentage of photons in the background of heavy ion collision (HIC) is a result of π0 and η decays. The decay width can be considered in terms of the transition form...
The paper will present the results of the study of the influence of relativistic rotation on the properties of quark-gluon matter. To carry out this study, we switch to a reference frame that rotates together with the system we study. In this reference frame, the rotation leads to the appearance of an external gravitational field, and the problem is reduced to the study of the properties of...
The equation of state (EoS) of asymmetric nuclear matter and its isospin dependence play a fundamental role in nuclear structure, reactions, and decays, as well as in neutron star properties and formation. To constrain the EoS robustly, studies must span extreme densities and pressures across nuclear and astrophysical systems. A well-determined EoS would provide critical insights into...
We investigate the sensitivity of the light nuclei and hypernuclei production to the strongly interacting nuclei matter equation-of-state (EoS) within the Parton-Hadron-Quantum-Molecular Dynamics (PHQMD) microscopic transport approach.
We study the effect of finite spin quark density on the chiral and deconfinement thermal transitions using numerical simulations of lattice QCD with two dynamical light quarks. The finite spin density is introduced by the quark spin potential in the canonical formulation of the spin operator. We show that both chiral and deconfinement temperatures are decreasing functions of the spin...
We have investigated the accelarating hot gluonic matter near the critical temperature of the deconfinement phase transition within the framework of lattice quantum field theory (QFT). We used the Tolman-Ehrenfest relation between the temperature gradient and the gravitational field to introduce acceleration into the lattice QFT formalism. We considered several lattice sizes along imaginary...
It has been shown in the framework of effective models that the QCD phase diagram as in three color case as well as in two color one possesses dualities. This means that various phenomena are dual with respect to each other. Then dualities were shown in a more and more general settings. Then finally dualities has been shown from first principles,three dualities as in two color QCD and one in...
In this project, we use the Einstein Gauss Bonnet gravity for this holographic model. The crust contains baryon phase correspond the instanton gas in AdS soliton solution and the core color supeconductivity (CSC) phase correspond to the AdS black hole. We use this model to compute the equation of state of this type of compact star
The thermodynamical approach to light (hyper)nuclei production in heavy-ion collisions and its implementation in the new version of the generator THESEUS (Three-fluid Hydrodynamics-based Event Simulator Extended by UrQMD final State interaction) are reviewed.
In this approach light (hyper)nuclei are treated on the equal basis with hadrons, i.e. using only thermodynamic quantities deduced...
Hypernuclei remain for a long time the major source of information on hyperonic interactions in nuclear environments. This information is useful for neutron star and heavy ion fields.
We discuss some topics on the modern status and recent progress in hypernuclear studies. Particularly, we consider exotic Λ hypernuclei with nuclear cores close to the drip lines. In some cases, the hyperon...
Interplay between recent progress in studies of thermal evolution of neutron stars and dense matter theory is discussed. Consideration is limited to the nucleonic composition of neutron-star interior. Passive cooling of isolated neutron stars is considered along with heating and cooling of accreting neutron stars in binary systems. Cases of practical interest are highlighted, where the usual...
Accurate estimates of (anti)neutrino spectra and luminosities are essential for assessing the possibility of detecting neutrinos from pre-supernova stars. Using the thermal quasiparticle random-phase approximation (TQRPA) method, we studied the effects of nuclear temperature on pre-supernova (anti)neutrino emission. Comparing the $\nu_e$ and $\bar\nu_e$ spectra produced in neutral- and...
There are plenty of models for the neutron star (NS) equation of state (EoS) on the astrophysical market. While they are very diverse (nucleonic, hyperonic, or hybrid, based on different microphysics), it is widely known that some macroscopic NS properties show universal correlations which are largely independent of a specific EoS model. Such universalities have several astrophysical...
Medium effects, which can be introduced in the Skyrme formalism as density-dependent or three-body forces, are an essential part of describing hyperonic interactions. In neutron stars, these effects are especially important due to the extremely high densities.
We study the influence of the different aspects of these medium effects on neutron stars characteristics. In particular, the role...
$R$-modes are oscillations of rotating stars, restored primarily by Coriolis force. Of all oscillations, they are the most susceptible to the Chandrasekhar-Friedmann-Schutz instability with respect to emission of gravitational waves. This instability makes them particularly promising targets for current and future gravitational wave searches. In order to develop, the CFS instability should...
Fragmentation reactions at energies from 35 to 140 MeV per nucleon are a powerful tool to obtain new isotopes far from stability line. To plan the future experiments model calculations should be performed. Usually models developed to describe relativistic heavy-ion collisions are used for this purpose, like the EPAX and the Abration-Ablation models. They perfectly predict the cross-sections...
Dynamics of heated droplets of particles interacting with Lennard-Jones potential are simulated by employing the classical molecular dynamics (CMD). Such large aggregates represent an example a finite system exhibiting the van der Waals equation of state in thermodynamic limit which properly characterizes the existence of spinodal region relevant for liquid-gas phase transition. We analyze an...
A strange star is a hypothesized compact star that is dense enough to literally break down ordinary neutrons into their constituent quarks. Furthermore, the up and down quarks are squeezed into an even rarer sort of quark known as a strange quark, which explains the name strange star. Technically, up, down, and strange quarks make up the "strange" matter of a strange star. This mixture of...
The equation of state (EoS) of neutron-rich matter defines the neutron star properties and structure of finite nuclei via the density dependence of symmetry energy. This calls for simultaneous description of both nuclear ground state characteristics, collective nuclear responses to external fields and mass-radii dependence for neutron stars within universal nuclear energy density functional. A...
One of the important processes leading to neutrino emission from the interior of superfluid neutron stars is the process of neutrino emission during Cooper pairing of neutrons. For instance, its rate is crucial for the explanation of the rapid cooling of the neutron star in the Cassiopeia A supernova remnant (if one assumes that the pair breaking and formation process is responsible for this...
We use the functional renormalization group to study the superfluid phase transition in unitary $SU(n)$-symmetric Fermi gases. For $n \geq 4$ critical fluctuations invalidate mean‐field theory and drive the transition first‑order. We calculate the critical temperature and the jumps in the superfluid gap and the entropy density as functions of spin multiplicity $n$. All discontinuities grow...
To gain a deeper insight into the dynamics of the quark-hadron phase transition
under a magnetic field, the thermal characteristics of the non-perturbative
QCD vacuum have been studied. The dynamic arrangement of the resulting
dual QCD vacuum and its flux tube structure has been examined to investigate
the non-perturbative features of QCD. The partition function of quarks
and gluons in...
I present an overview of recent developments in the measurements of spin-polarization in heavy ion collisions and the formulation of spin-hydrodynamics.
The influence of environmental effects and proton superconductivity in the matter of neutron stars on the evolution of stellar cooling is studied. It is shown that using cooling models and observational data on the temperature and age of pulsars, it is possible to extract the masses of the observed objects and the mass spectrum of neutron stars.
We will discuss the computation of spectral functions of bound states using the real-time formulation of a functional renormalization group (FRG) approach on the example of the O(4) model. The computation is based on the Kallen-Lehmann spectral representation of dressed propagators used in the Wetterich equation -- the flow equation of the effective action. We consider an approximation of...
The confinement problem still remains an important topic in quantum chromodynamics (QCD). At the moment, there is no acceptable way to describe the low-energy limit of QCD, at which non-pertubative effects appear, except for lattice modeling. In my work, using lattice QCD methods, I considered flux tubes connecting a quark - antiquark pair, with additional boundary conditions in the form of a...
Percolation models are widely recognized in statistical physics for providing the simplest example of a phase transition and critical phenomenon. Bonds of an infinite lattice chosen to be open at random with probability $p$ and closed otherwise form an infinite cluster when $p$ exceeds a critical value. The statistics of open clusters show typical critical behavior at the critical point, like...
The talk offers a concise overview of recent advancements in the study of the inner crust, focusing on refinements in trial functions for extended Thomas-Fermi (ETF) calculations and their impact on predictions regarding the structure of the pasta phase. We will also discuss the specifics of thermodynamically consistent calculations of pressure and chemical potential within ETF framework...
Conditions are found, at which in the nuclear matter there may appear a spatially nonuniform $p$ wave $\pi^0$ condensate supplemented by a spatially varying spontaneous magnetization. The pion-nucleon interaction and the anomaly contributions to the magnetization are taken into account. Response of the system on the external magnetic field is also considered. Then the model of...
Heavy ion collisions produce matter with extreme vorticity and acceleration, sparking strong theoretical and experimental interest. I will discuss theoretical results on the (acceleration-temperature) phase diagram for spin-1/2 particles, predicting a new phase transition below the Unruh temperature. This transition links to an effective black hole in an accelerated frame, namely, with the...
