The spectrum of Ds mesons from lattice QCD

The spectrum of orbitally excited Ds mesons is computed in the continuum limit of quenched lattice QCD. The results are consistent with the interpretation that the narrow resonance in the Dsπ0 channel discovered by the BaBar Collaboration is a JP=0+ cs̄ 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 Ds mesons with two flavors of dynamical quarks, with mass slightly larger than the strange quark mass. These results are consistent with the quenched data.