Energies and radial distributions of B_s mesons - the effect of hypercubic blocking

TL;DR

This study investigates the radial distributions of higher angular momentum states in B_s mesons using lattice QCD with hypercubic blocking, providing new insights into heavy-light meson structure.

Contribution

It introduces hypercubic blocking in the time direction for lattice QCD calculations of B_s mesons, extending analysis to P- and D-wave states with dynamical fermions.

Findings

Radial distributions for P- and D-wave states are computed.

Hypercubic blocking improves heavy quark localization within a hypercube.

Results aid in understanding B_s meson structure in terms of the Dirac equation.

Abstract

This is a follow-up to our earlier work for the energies and the charge (vector) and matter (scalar) distributions for S-wave states in a heavy-light meson, where the heavy quark is static and the light quark has a mass about that of the strange quark. We study the radial distributions of higher angular momentum states, namely P- and D-wave states, using a "fuzzy" static quark. A new improvement is the use of hypercubic blocking in the time direction, which effectively constrains the heavy quark to move within a 2a hypercube (a is the lattice spacing). The calculation is carried out with dynamical fermions on a 16^3 times 32 lattice with a lattice spacing approximately 0.10 fm generated using the non-perturbatively improved clover action. The configurations were generated by the UKQCD Collaboration using lattice action parameters beta = 5.2, c_SW = 2.0171 and kappa = 0.1350. In nature the closest equivalent of this heavy-light system is the B_s meson. Attempts are now being made to understand these results in terms of the Dirac equation.