Numerical results for QED ISR corrections to the cross-section of the e+e- annihilation process at future collider energies are presented. Dependence on factorization scale choice and subtraction scheme is discussed.
Masses of tetraquarks with two heavy quarks ($\rm QQ^{'}\bar q\bar q^{'}$) are calculated within the relativistic quark model, based on the quasipotential approach and QCD, and diquark--antidiquark picture of tetraquarks. The relativistic quasipotential equation takes into account all spin-dependent and spin-independent relativistic corrections and the internal structure of the diquarks. The...
In our work, we consider the process of associated charmonium and jet production.
One of the reasons why it is difficult to study charmonium hadronization process is
the non-perturbative nature of this state, which can only be described within the
framework of phenomenological models. Moreover, a double parton scattering
(DPS) contribution can be dominating in certain kinematic regions of...
We analyze Higgs decay $H \rightarrow f \overline{f}$ allowing for final states with nonzero angular momentum ("twisted" states). We construct the two-particle wavefunction from the S-matrix element in momentum space and transform it to coordinates. In the Higgs rest frame the wavefunction depends solely on the relative coordinate $r$ and the spin orientations, enabling a spherical-harmonic...
We demonstrate how extended gravity theories can be derived from the ะฒeformation of topological BF field theory. Initially, BF gravity can be deformed by the disformal modification of theoryโs internal fields. This transformation leads to the appearance of a scalar-tensor gravity action. Thus, one generates the theory that includes the inflaton field, as opposed to earlier models (e.g....
In the report, the off-shell electromagnetic pion form factors in the Bethe-Salpeter formalism are considered. The separable kernel of the first rank quark-antiquark interaction is used to solve the equation analytically. The half-off-shell pion form factors $F_1$ and $F_2$, which are related to each other by the Ward-Takahashi identity, are calculated. The obtained off-shell form factors as...
The Skyrme energy density functional have applied to calculate the nucleus-nucleus interaction potentials for sub-barrier fusion reactions within the framework of double-folding model. It is shown that the calculated potential is sensitive to the velocity-dependent terms in the Skyrme EDF. To accurately capture the height of the Coulomb barrier, it is essential to amplify the contribution from...
Studies of non-perturbative effects of quantum electrodynamics (QED) in extremely strong electromagnetic fields have been carried out for decades and remain one of the most topical problems of modern physics. Special attention is paid to the spontaneous decay of the vacuum in collisions of heavy ions. When nuclei with the total charge $Z > Z_{\text{cr}}$, where $Z_{\mathrm{cr}} \approx 173$,...
The research investigates rare processes in photon-photon collisions (light-by-light scattering and the production of hypothetical scalar and pseudoscalar (ALP) particles) using photon beams of the future project of the NCPhM Compton source, based on the inverse Compton effect: the photon beam generated by the Compton source collides with a photon beam from a laser.
- A previously unknown...
We investigate the properties of $SU(3)$ gluon plasma at high temperature under acceleration using lattice simulations in Rindler coordinate. Our results reveal a spatial crossover transition from confinement to deconfinement opposite to the direction of acceleration, consistent with the Tolman-Ehrenfest (TE) law. Using this law, we renormalize the Polyakov loop in Rindler space. Additionally,...
This study computes the phonon density of states (PhDOS) of graphite using first-principles density functional theory (DFT) with the open-source Quantum ESPRESSO package. The results provide insights into the vibrational properties of crystalline graphite that govern thermal scattering processes. The phonon spectrum, regarded as a probability density function, serves as essential input for...
Third- and fourth-order FEM schemes with multivariate Hermite interpolation polynomials of a $d$ $-$ dimensional hypercube for solving boundary value problems (BVP's) on hyperparallelepipedal meshes are elaborated. An exactly solvable model of a system of several identical particles with pair oscillator interaction known as the Moshinsky atom is used as a test example. To describe the energy...
Rapidly moving neutron stars are believed to gain high linear velocities โ kicks โ in aspherical supernova explosions. The mechanism of the kick formation is probably connected with anisotropic neutrino flash, and/or anisotropic matter ejection during the explosion. In this paper, we investigate a neutron star's kick origin due to a recoil effect in a magnetorotational (MR) supernova explosion...
Using the dispersive approach to the axial anomaly, both Abelian and non-Abelian cases are considered. Anomalous sum rules for isovector, octet and singlet currents are derived, which allow us to extract the nonperturbative gluon matrix element $\langle 0 |G\tilde{G}|\gamma\gamma^{(*)} \rangle$ from experimentally measured transition form factors $\pi^0,\eta,\eta'\rightarrow\gamma\gamma^{(*)}$...
An experiment aimed at detecting nuclear spin-dependent parity-violating effects in the ยฒโนSiยนโถOโบ cation [1] is currently being prepared by an international collaboration of scientists based at the Massachusetts Institute of Technology. A clear understanding of the electronic structure of this molecule is required for both setting up the experiment and interpreting its results. This topic has...
Most registrations of gravitational waves are made using the matched-filter method, which compares data from detectors (LIGO, VIRGO, KAGRA) with pre-modelled signals (templates). The template banks used by LIGO are based on the post-Newtonian formalism for the inspiral phase and on numerical relativity calculations for the merger and ringdown phases. However, there is a need in faster...
We present a systematic analysis of Coulomb corrections for the interaction of charged leptons in the final state in lepton and semi-lepton decays of neutral $B$-mesons. The calculation is performed within the Furry picture. For scalar systems, a comparison is made between the nonrelativistic Gamow-Sommerfeld-Sakharov approximation, the exact relativistic method of Crater-Alstine-Sazdjian, and...
In this report we present the results of our study of rotating gluodynamics. In particular, we carry out lattice calculation of total angular momentum of rotating gluodynamics for various temperatures and angular velocities within local thermalization approximation. In this approximation, instead of simulating the full action, we use the action with the coefficients being fixed at some...
In continuation of a series of works on the study of medium effects in the heavy-ion collisions at the NICA complex energies [1-4], current investigation is focused on the acceleration and the Unruh temperature of the hadron and parton phases [5]. The analysis is performed within the framework of the Parton-Hadron-String Dynamics (PHSD) model. An acceleration in heavy-ion collisions signifies...
The properties of light and heavy quark-antiquark bound states are investigated within a model featuring a nonlocal interaction. The framework is based on the Bethe-Salpeter equation with Gaussian-type vertex function that defines the nonlocal interaction kernel. The model parameters are constrained by experimental data on electromagnetic and leptonic decay constants. This model is used to...
Photoelectron circular dichroism (PECD) [1] is a well-known phenomenon resulting in asymmetry in the angular distribution of photoelectrons produced in the ionization of randomly oriented chiral molecules in a gas by circularly polarized light relative to the direction of light propagation. Recent advances have extended this concept to vortex electrons, where the ejected photoelectron has a...
The TMD factorisation is a theoretical approach for description of hard processes at small transverse momentum domain [1]. The Soft Gluon Resummation approach is a model to obtain expressions for TMD parton distributions and take into account their evolution [2, 3]. Unpolarised $J/\psi$ production can be quite satisfyingly described within this model [4, 5]. In this study, we estimate angular...
This talk is devoted to calculations in critical dynamic models using parametric integration with Goncharov polylogarithms, previously successfully applied in static problems and stochastic models of fully developed turbulence. The principal difficulty of dynamic calculations compared to static ones lies in the increase in the number of diagrams and the growing complexity of their structure....
The low-energy multipole spectrum in isotopes $^{250-260}No$ is investigated in the framework of fully self-consistent Quasiparticle-Random-Phase-Approximation (QRPA) method [1, 2] with Skyrme forces. The main attention is paid to nuclei $^{250,252,254}No$, where we have most of the experimental spectroscopic information [3, 4]. In general, a good agreement with the experimental data is...
When assessing the potential for discovering new physics beyond the Standard Model (SM) at the ILC and CLIC, a crucial role is assigned to the statistical treatment of experimental data, which is inherently linked to the specifics of the experimental setup and other factors. However, even in the absence of actual experimental data, it is possible to preliminarily estimate and study potential...
In the framework of the well-known trinuclear system (TNS) model, we describe the formation process of fission isomers (considered here as the dinuclear system) in spontaneous ternary fission of $^{252}Cf$. The influence of the Coulomb field of the foil nuclei on decay barriers and half-life times of fission isomers is shown. Calculated results indicate that Coulomb field effects more strongly...
Numerical results for QED ISR corrections to the cross-section of the e+e- annihilation process at future collider energies are presented. Dependence on factorization scale choice and subtraction scheme is discussed.
In the report, the off-shell electromagnetic pion form factors in the Bethe-Salpeter formalism are considered. The separable kernel of the first rank quark-antiquark interaction is used to solve the equation analytically. The half-off-shell pion form factors $F_1$ and $F_2$, which are related to each other by the Ward-Takahashi identity, are calculated. The obtained off-shell form factors as...
