Decay constants ofP-wave heavy-light mesons from unquenched lattice QCD

Abstract

We review some decays that require knowledge of the decay constants of ${0}^{+}$ heavy-light mesons. We compute the decay constants of $P$-wave heavy-light mesons from unquenched lattice QCD, with two degenerate flavours of sea quarks, at a single lattice spacing. The lightest sea quark mass used in the calculation is a third of the strange quark mass. For the charm-strange meson we obtain the decay constant: ${f}_{{D}_{s{0}^{+}}}=340(110)\text{ }\text{ }\mathrm{MeV}$ using our normalization conventions. We obtain the ${f}_{{P}_{s}}^{\mathrm{static}}$ (static-strange $P$-wave) decay constant as $302(39)\text{ }\text{ }\mathrm{MeV}$.