New Charm Spectroscopy: Insights from Theory

Abstract

We discuss several new observations of mesons with open charm. In particular, we consider $D_{sJ}(2317)$ and $D_{sJ}(2460)$ and compare their isospin violating decays into $D^{(*)}_s \pi$ to the radiative decays analysed using light-cone QCD sum rules. The results support the interpretation of these two mesons as ordinary $c{\bar s}$ states. In the case of $D_{sJ}(2860)$ and $D_{sJ}(2710)$ we compute the strong decays in the heavy quark limit. Comparison of the results with recent measurements of the BaBar Collaboration leads to identify $D_{sJ}(2710)$ with the first radial excitation of $D_s^*$, while the identification is still uncertain in the case of $D_{sJ}(2860)$.