The spectrum of D_s mesons from lattice QCD

TL;DR

This paper computes the spectrum of orbitally excited D_s mesons using lattice QCD, confirming experimental observations and theoretical predictions, including the structure of mass splittings and resonance interpretations.

Contribution

It provides the first study of orbitally excited D_s mesons with two dynamical quark flavors and compares quenched and unquenched results, advancing understanding of meson spectra.

Findings

Results align with experimental resonance in D_s π^0 channel.

Mass splittings match heavy hadron chiral effective theory predictions.

Unquenched results are consistent with quenched data.

Abstract

The spectrum of orbitally excited $D_s$ mesons is computed in the continuum limit of quenched lattice QCD. The results are consistent with the interpretation that the narrow resonance in the $D_s \pi^0$ channel discovered by the BABAR Collaboration is a $J^P=0^+$ $c\bar{s}$ meson. Furthermore, within statistical errors, the $1^+-1^-$ and the $0^+-0^-$ mass splittings are equal, in agreement with the chiral multiplet structure predicted by heavy hadron chiral effective theory. On our coarsest lattice we present results from the first study of orbitally excited $D_s$ mesons with two flavors of dynamical quarks, with mass slightly larger than the strange quark mass. These results are consistent with the quenched data.