S and P-wave heavy-light mesons in lattice NRQCD

TL;DR

This study computes the mass spectrum of S and P-wave heavy-light mesons using lattice NRQCD, revealing significant higher-order corrections for charmed mesons and negligible corrections for bottom mesons, with results compared to experimental data.

Contribution

It provides a detailed lattice NRQCD calculation of heavy-light meson spectra including higher-order corrections and explores various lattice improvements, enhancing understanding of meson mass splittings.

Findings

Second order correction to charmed S-wave spin splitting is about 20% of the leading order.

Third order correction is about 20% for D^*-D and D_s^*-D_s mass splittings.

Nonleading corrections are very small for bottom mesons and insignificant for P-wave charmed masses.

Abstract

The mass spectrum of S and P-wave mesons containing a single heavy quark is computed in the quenched approximation, using NRQCD up to third order in the inverse heavy quark mass expansion. Previous results found third order contributions which are as large in magnitude as the total second order contribution for the charmed S-wave spin splitting. The present work considers variations such as anisotropic lattices, Landau link tadpole improvement, and a highly-improved light quark action, and finds that the second order correction to the charmed S-wave spin splitting is about 20% of the leading order contribution, while the third order correction is about 20%(10%) for D^*-D(D_s^*-D_s). Nonleading corrections are very small for the bottom meson spectrum, and are statistically insignificant for the P-wave charmed masses. The relative orderings among P-wave charmed and bottom mesons, and the sizes of the mass splittings, are discussed in light of experimental data and existing calculations.