$D_{(s)}^{\ast }\to P$ form factors and their applications to semi-leptonic and non-leptonic weak decays

Abstract

Similar to other heavy flavor mesons, the weak decays of $D_{(s)}^{\ast }$ mesons can provide a platform to verify the standard model, explore new physics, and understand the mechanisms of weak interactions. At present, the theoretical and experimental studies on $D_{(s)}^{\ast }$ mesons are relatively limited. In addition to the dominant electromagnetic decays, the $D_{(s)}^{\ast }$ weak decays should be feasible to explore the $D_{(s)}^{\ast }$ mesons. In this study, we used the covariant light-front quark model to study the form factors of the transitions $D_{(s)}^{\ast }\to \pi ,K,{\eta }_{q,s}$, then calculated the branching ratios of the semi-leptonic decays $D_{(s)}^{\ast }\to P{\ell }^{+}{\nu }_{\ell }$ and the non-leptonic decays $D_{(s)}^{\ast }\to PP,PV$ with $P=\pi ,K,{\eta }^{(\prime )},V=\rho ,K^{\ast },\varphi$ and $\ell =e,\mu$. The channels $D_s^{\ast +}\to \eta {\ell }^{+}{\nu }_{\ell }$ and $D_s^{\ast +}\to \eta {\rho }^{+}$ possess the largest branching ratios, which can reach an order of $10^{-6}$ among these decays, and are most likely to be accessible in experiments at future high-luminosity colliders. Furthermore, we predict and discuss the longitudinal polarization fraction $f_L$ and the forward-backward asymmetry $A_{FB}$ for the considered semi-leptonic $D_{(s)}^{\ast }$ decays.

Comments: 23 pages, 4 figures. arXiv admin note: text overlap with arXiv:2311.04431