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Information × Registration Number 0224U033501, (0121U108812) , R & D reports Title Studies on the properties of fundamental interactions in nuclear reactions, structure of exotic nuclei, high-energy physics, particle astrophysics, and cosmology popup.stage_title Поляризаційні ефекти в народженні топ-кварків в електрон- позитронній анігіляції при високих енергіях. Аналіз впливу квантових ефектів на механізми генерації частинок ультра- високих енергій поблизу активних галактичних ядер і надмасивних чорних дір. Head Korchyn Oleksandr Yu., д.ф.-м.н. Registration Date 29-12-2024 Organization National Science Center "Kharkiv Institute of Physics and Technology" popup.description1 Analysis of polarization effects in the reaction of electron-positron annihilation into a pair of top quarks (t-quarks) with the decay of the latter into bottom quarks (b-quarks), leptons and neutrinos, in order to study the coupling constants of t-quarks with photons and Z- bosons. Investigation and calculations of observables in semi-leptonic decays of B_c mesons to different states of charmonium. Model-independent analysis of the reaction of scalar- or vector-meson production (with the formation of nucleon-antinucleon pair) in electron-positron collisions. The amplitude of these reactions takes into account contribution of a number of known nucleon resonances with spins 1/2 and 3/2. Calculation of expressions for different observables (including polarization) in terms of transition electromagnetic form factors of the nucleon. A separate consideration of the case in which the amplitude does not include resonances (the Born approximation). An important goal of our research is building a new family of current operators due to exchange of clothed mesons between clothed nucleons. Our search in this direction is based on the clothing procedure, which was put forward a few years ago in relativistic quantum field theory (more precisely for its instantaneous form) by Greenberg and Schweber, and developed by collaboration between LTP (Dubna), INFN (University of Padowa, Italy) and ITP KIPT (Kharkov). Further development and refinement of the Dirac multiple eikonal scattering model for description of the p-A collisions at intermediate energies, based on realistic pN-amplitudes, and calculations of the nuclei structure in the relativistic mean-field approximation, analysis of the corresponding cross sections and spin observables, and investigation of the role of corrections in this model. popup.description2 The paper considers the process of top quark and anti-top quark formation in electron-positron annihilation. The energy distributions of bottom quarks and anti-bottom quarks are investigated within the Standard Model (SM) and taking into account the contributions of physics outside it. The main attention is paid to the analysis of the effects of CP-symmetry violation in the interaction of the photon and Z boson with top quarks. Asymmetries of energy distributions are proposed that depend on the CP-violating terms of the Lagrangian. The dependencies of these asymmetries on the invariant energy up to 1.2 TeV are calculated, and their behavior is analyzed taking into account the partial polarization of the initial electron beam. The obtained results indicate that similar observables can be experimentally measured at future electron-positron colliders. It was shown under which conditions quantum effects in the dynamics of black holes cannot be neglected. Taking into account quantum effects, a singular behavior of the momentum density vector was obtained, corresponding to jets of bipolar radiation from the black hole and energy emissions within the accretion disk. A model was developed that provides a more detailed description of Active Galactic Nuclei than previously proposed models. Product Description popup.authors Korchyn Oleksandr Yu. Nurmahambetov Oleksii Yu. Truten Ivan V. popup.nrat_date 2024-12-29 Close