$B_s\to D_s(3040)$ form factors and $B_s$ decays into $D_s(3040)$

TL;DR

This paper calculates the form factors for $B_s$ decays into $D_s(3040)$ using a covariant light-front quark model, predicts decay rates, and explores how polarization and angular measurements can clarify the quantum numbers of $D_s(3040)$.

Contribution

It provides the first detailed calculation of $B_s o D_s(3040)$ form factors and decay predictions within the covariant light-front quark model, considering different classification schemes for $D_s(3040)$.

Findings

Branching ratios for $B_s o D_s(3040) o ext{leptons}$ are around $10^{-3}$ for electrons and muons, and $10^{-5}$ for taus.

Polarization fractions and angular asymmetries can help determine the quantum numbers of $D_s(3040)$.

Nonleptonic decay branching ratios are of order $10^{-3}$ for certain channels like $B_s o D_s(3040) ho$.

Abstract

Under the assignment of $D_s(3040)$ as a radially excited p-wave $\bar cs$ state with $J^P=1^+$, we compute the $B_s\to D_s (3040)$ form factors within the covariant light-front quark model. Two classification schemes for the p-wave $\bar cs$ meson are adopted. We also use our results to predict the branching ratios (BRs), polarization fractions and angular asymmetries in semileptonic $B_s\to D_s(3040)\ell\bar\nu(\ell=e,\mu,\tau)$. The BRs are found to have the order of $10^{-3}$ for $\ell=e,\mu$ and $10^{-5}$ for $\ell=\tau$. We find that the polarization fractions and the angular asymmetries could be useful to pin down the ambiguities of the quantum numbers for $D_s(3040)$. In addition, we investigate the nonleptonic $B_s\to D_s(3040)M$ decays under the factorization method, where $M$ denotes a charged pseudoscalar or a vector meson. The BRs of $B_s\to D_s(3040)\rho$ and $B_s\to D_s(3040)D_s^*$ reach the order of $10^{-3}$, while the other channels are typically smaller by 1-2 orders.