Bs→Ds(3040)form factors andBsdecays intoDs(3040)

Abstract

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