Selected decays of $B_s$ meson in covariant confined quark model

Abstract

We present a study of various $B_s$ meson decays, including hadronic and semileptonic final states with different spins and diagram topologies. The covariant confined quark model is employed to describe hadronic effects, and our analysis serves as a broad test of the current understanding of the underlying dynamics within the Standard Model. The level of agreement with experimental data varies across channels: it is good for the semileptonic decays $B_s^0\to D_s^{-}{\mu }^{+}{\nu }_{\mu }$ and $B_s^0\to K^{-}{\mu }^{+}{\nu }_{\mu }$; acceptable for the hadronic modes $B_s^0\to D_s^{-}{D}^{+}$ and $B_s^0\to K^{-}{\pi }^{+}$; marginal for $B_s^0\to D_s^{-}{\pi }^{+}$, $B_s^0\to D_s^{-}{\rho }^{+}$, and $B_s^0\to \varphi J/\psi$; and significantly discrepant for $B_s^0\to \varphi \overline{D^0}$ and $B_s^0\to \varphi {\eta }_c$. We argue that the observed inconsistencies may arise from the breakdown of naive factorization and unaccounted long-distance effects. In particular, the channels $B_s^0\to D_s^{-}{\pi }^{+}$ and $B_s^0\to D_s^{-}{\rho }^{+}$ are theoretically among the cleanest nonleptonic decays, yet they exhibit persistent discrepancies also reported by other theoretical groups.