A Prediction of the B*_c mass in full lattice QCD

TL;DR

This paper uses advanced lattice QCD techniques to accurately predict the B*_c meson mass, demonstrating minimal dependence on light quark masses and providing the most precise lattice QCD prediction for a stable hadron to date.

Contribution

It introduces a novel combination of Highly Improved Staggered Quark formalism and NRQCD to precisely predict the B*_c mass, improving accuracy over previous methods.

Findings

Predicted B*_c mass as 6.330 GeV with small uncertainties.

Found the mass splitting ratio (m(B*_c)-m(B_c))/(m(B*_s)-m(B_s)) to be 1.15(15).

Demonstrated minimal light quark mass dependence in the splitting.

Abstract

By using the Highly Improved Staggered Quark formalism to handle charm, strange and light valence quarks in full lattice QCD, and NRQCD to handle bottom valence quarks we are able to determine accurately ratios of the B meson vector-pseudoscalar mass splittings, in particular, (m(B*_c)-m(B_c))/(m(B*_s)-m(B_s)). We find this ratio to be 1.15(15), showing the `light' quark mass dependence of this splitting to be very small. Hence we predict m(B_c*) = 6.330(7)(2)(6) GeV where the first two errors are from the lattice calculation and the third from existing experiment. This is the most accurate prediction of a gold-plated hadron mass from lattice QCD to date.