Strong decays of newly observed charm-strange meson states based on a relativistic model

Abstract

The mass spectra of charm-strange mesons including ground, radial and orbital excitations have been calculated within a relativistic Dirac framework. The predicted masses of the ground state $1S$ and the first orbital excited state $1P$ exhibits excellent agreement with values reported by the PDG. Utilizing these mass predictions and an effective Lagrangian approach based on heavy quark and chiral symmetries, we have computed the OZI allowed two body strong decay widths of higher excited state candidates of charm-strange sector. The resulting partial widths and branching ratios enable the assignment of spin-parity quantum numbers to several newly observed charm-strange states. In particular, we identify $D_{sJ}(2700)$ as the $2^3{S}_1$, $D_{s0}(2590)$ as the $2^1{S}_0$, $D_{sJ}(2860)$ as the $1^3{D}_3$, $D_{s1}(2860)$ as the $1^3{D}_1$, and $D_{sJ}(3040)$ as the $2^1{P}_1$ states. The effective coupling constants $g_T$, $g_X$, $g_Y$, ${\tilde{g}}_S$ and ${\tilde{g}}_H$ extracted from present analysis. Furthermore, the $D^{\ast }K$ decay channel emerges as the most promising mode for the experimental search of the missing $1^3{D}_2$ and $1^1{D}_2$ states, while the $2^3{P}_0$ state is more likely to be observed through the $DK$ channel.