We have made a three-loop quark model calculation of the W-exchange contribution to the nonleptonic two-body decays of the doubly charmed baryons Ξ_cc and Ω_cc. The W-exchange contributions appear in addition to the factorizable tree graph contributions and are not suppressed in general. We make use of the covariant confined quark model previously developed by us to calculate the tree graph...
We present the branching fractions for the rare semileptonic decay $B \to \omega \ell^+ \ell^-$ for $\ell = e, \mu, \tau$. The necessary transition form factors are computed in the entire range of momentum transfer within the Standard Model framework of Covariant Confined Quark Model with built-in infrared confinement. We further compute different physical observables such as forward backward...
The mixing angle of the vector $\omega$ and $\phi$ mesons is estimated in the framework of Nambu - Jona-Lasinio model. The decay $\phi \to \pi^{0} \gamma$ is considered as a basic process to determine this angle. The obtained value is compared with the results of the other authors. Besides, the width of the decay $\phi \to 3\pi$ and the cross-section of the process $e^{+}e^{-} \to \pi^{0}...
In ultrarelativistic heavy-ion collision (NICA, FAIR, etc.) the creation of quark-gluon plasma with a nonzero angular momentum is expected, especially in off-central collision. The rotation of QCD matter shoud leads to a number of nontrivial physical phenomena, and further study of rotation is of a great interest. In this work the influence of the rotation on the confinement/deconfinement...
This report is devoted to lattice study of QCD equation of state (EoS) at finite baryon chemical potential and nonzero magnetic field. The simulations are performed with rooted dynamical staggered $u$, $d$, and $s$ quarks at physical quark masses. In view of the sign problem, the study is carried out at imaginary chemical potential. The results are analytically continued to real chemical...
We study Hamiltonian form of unfree gauge symmetry where the gauge parameters have to obey differential equations. The phenomenon of the unfree gauge symmetry is clarified from viewpoint of involution relations between Hamiltonian and constraints. Given the involution relations for the first-class constraints of all generations, we provide explicit formulas for unfree gauge transformations in...
In this talk we are going to discuss recent results on non-Abelian vortex strings in four-dimensional (4D) $\mathcal{N} = 2$ supersymmetric QCD with U$(N=2)$ gauge group and $N_f=4$ flavors of quark hypermultiplets.
It has been recently shown that these vortices behave as critical superstrings. The spectrum of closed string states in the associated string theory was found and interpreted...
In my talk, I'll briefly describe recent results in the field of calculation of multi-loop and phase-space integrals arising in many QFT problems. Included problems with various masses and scales in different space-time dimensions. We give a review of modern methods and calculation setups needed for performing such complicated problems with available computer resources.
We generalize the dispersive approach to axial anomaly by A.D. Dolgov and V.I. Zakharov to a non-Abelian case with arbitrary photon virtualites. We derive the anomaly sum rule for the singlet current and obtain the $\pi^0,\eta,\eta' \rightarrow \gamma \gamma^{(*)}$ transition form factors. Using them, we established the behavior of a non-perturbative gluon matrix element $\langle 0 |G\tilde{G}...
Although the Standard Model (SM) has become the main theory that describes modern Particle Physics, it fails to answer a number of questions. The most famous of «problems beyond the SM» is the origin of neutrino mass, while SM considers only left massless neutrinos.
To explain «problems beyond the SM», it is necessary to introduce new particles and interactions, which haven't yet been...
Experimental data on $ ^ {96} $Zr indicate in this nucleus the coexistence of spherical and deformed structures with small mixing amplitudes. Several low-lying collective quadrupole states and the probabilities E2 and M1 of transitions between them are known in this nucleus. In our work, the observed properties of low-lying collective states of $ ^ {96} $Zr are investigated on the basis of a...
The coexistence of forms is an interesting phenomenon that can occur in many nuclei. At the moment, there are experimental data that indicate the coexistence of spherical and deformed shapes in $^{96}$Zr and $^{96}$Mo. In this work, the observed properties of low-lying collective excitations $^{96}$Zr and $^{96}$Mo are investigated within the framework of the geometric collective nuclear model...
We investigate the Coulomb breakup of the $^{11}$Be halo nuclei on a heavy target at intermediate (70 MeV/nucleon) energies within non-perturbative time-dependent approach. The convergence of the computational scheme is demonstrated in all considered range of the energy including the low-lying resonances \textit{n}+$^{10}$Be in different partial and spin states of $^{11}$Be. The obtained...
Unlike the standard statistical distribution, for some states the Wigner function takes negative values, and this property is generally considered to be an indicator of quantumness of a system. We analyze the global indicator of classicality for N-level quantum systems, which is based on the negative part of the Wigner function and defined on the orbit space of a quantum system endowed with a...
It was Wigner and Weyl who investigated quantum systems in phase space. The Wigner function determines the density of quasi-probabilities of the random radius vector and momentum. Weyl-Wigner-Moyal-Groenewold formalism is widely used. Also Wigner function has a representation as a trace of the product of the density matrix by the kernel operator.
This paper suggests new explicit...
