Possible 2S and 1D charmed and charmed-strange mesons

TL;DR

This paper analyzes possible excited charmed and charmed-strange mesons, using Regge trajectories and decay calculations, to identify their quantum states and propose new meson candidates based on recent experimental data.

Contribution

It provides a detailed theoretical interpretation of newly observed mesons, suggesting their quantum states and possible mixing, and predicts the existence of an unobserved meson.

Findings

D(2550)^0 is a good candidate for 2^1S_0 state.

D*(2600) and D_{s1}*(2700) are likely mixtures of 2^3S_1 and 1^3D_1 states.

D*(2760) and D_{sJ}*(2860) are possible 1^3D_3 states.

Abstract

Possible $2S$ and $1D$ excited $D$ and $D_s$ states are studied, the charmed states $D(2550)^0$, $D^\ast(2600)$, $D(2750)^0$ and $D^\ast(2760)$ newly observed by the BaBar Collaboration are analyzed. The masses of these states are explored within the Regge trajectory phenomenology, and the strong decay widths are computed through the method proposed by Eichten {\it et al.}\cite{Eichten}. Both the mass and the decay width indicate that $D(2550)^0$ is a good candidate of $2^1S_0$. $D^\ast(2600)$ and $D_{s1}^\ast(2700)^\pm$ are very possible the admixtures of $2^3S_1$ and $1^3D_1$ with $J^P=1^-$ and a mixing angle $\phi\approx 19^0$. $D^\ast(2760)$ and $D_{sJ}^\ast(2860)^\pm$ are possible the $1^3D_3$ $D$ and $D_s$, respectively. $D(2750)^0$ and $D^\ast(2760)$ seem two different states, and $D(2750)^0$ is very possible the $1D(2^-, \frac{5}{2})$ though the possibility of $1D(2^-, \frac{3}{2})$ has not been excluded. There may exist an unobserved meson $D_{sJ}(2850)^\pm$ corresponding to $D^\ast_{sJ}(2860)^\pm$.