Form factors of the B-S-transitions in the covariant quark model

Abstract

In the wake of exploring uncertainty in the full angular distribution of the $B\to K\pi +{\mu }^{+}{\mu }^{-}$ caused by the presence of the intermediate scalar $K_0^{\ast }$ meson, we perform the straightforward calculation of the $B(B_s)\to S$ (S is a scalar meson) transition form factors in the full kinematical region within the covariant quark model. We restrict ourselves by the scalar mesons below 1 GeV: $a_0(980),f_0(500),f_0(980),K_0^{\ast }(800)$. As an application of the obtained results we calculate the widths of the semileptonic and rare decays $B(B_s)\to S\ell \bar{\nu }$, $B(B_s)\to S\ell \bar{\ell }$ and $B(B_s)\to S\nu \bar{\nu }$. We compare our results with those obtained in other approaches.

Comments: 13 pages, 5 figures, discussion and references added, to appear in Phys. Rev. D