B→ρB \to \rho Decay Form Factors from Covariant Confined Quark Model

We evaluate $B \rightarrow \rho$ transition form factors in the full kinematical region within the covariant confined quark model. We compare the obtained results with the results from light-cone sum rules. The calculated form factors can be used to calculate the $B^+ \rightarrow \rho^+ {\mu}^+ {\mu}^-$ rare decay branching ratio.Comment: arXiv admin note: substantial text overlap with arXiv:1907.1320

Using Von Mises-fisher Distribution for Polymer Conformation Analysis in Multi-scale Framework

AbstractIn this study we consider the statistical representation of polymer conformations, which is very important when modeling rheology at macroscopic scales. It is impossible to track all relevant microscopic variables for each polymer in a polymer-laden solution due to the huge number degrees of freedom associated with such fluids. We applied this approach to one of the most descriptive kinetic models of polymer, Kramers bead-rod model, where the probability density function models the angle of each rod with respect to the fixed coordinate axes. Towards this goal we apply mixture of von Mises-Fisher distribution for modeling a polymer conformation. The Expectation-Maximization based clustering algorithms are used to estimate the conformation given the ensemble of polymers. Both distribution sampling and parameters estimation have been implemented in parallel using CPU and GPU based platforms

Bc∗B^{*}_c meson parameters and radiative decay width within the covariant confined quark model

In this work we tried to predict the parameters of $B^{*}_c$ meson. Simple assumptions gave us following parametres $m_{B_{c}^{*}}=6329\pm 10$ MeV and $f_{B_{c}^{*}}= 535.5\pm57.8$ MeV (for $\Lambda_{B_{c}^{*}}=2.26\pm 0.14$ GeV in covariant confined quark model). We calculated widths of radiative decays of $B^*_{q}$ mesons, where $q=u/d,s,c$ and compared them with other theoretical works. It was shown that the width of the $B_{c}^{*}$ meson very sensitive to the mass $m_{B_{c}^{*}}$ as expected and less to the size parameter $\Lambda_{B_{c}^{*}}$