Semileptonic B Decays from an NRQCD/D234 Action

TL;DR

This paper investigates semileptonic B decays using advanced lattice QCD techniques, providing new form factor calculations and analyzing systematic uncertainties, especially from chiral extrapolation.

Contribution

It introduces a combined use of NRQCD and D234 actions on anisotropic lattices for more precise B decay form factor calculations.

Findings

Form factors for B --> pi, l nu decay computed and compared with previous results.

Systematic errors mainly from chiral extrapolation, excluding quenching errors.

Results contribute to more accurate theoretical predictions of B decay processes.

Abstract

Semileptonic B decays are studied on quenched anisotropic lattices using Symanzik improved glue, NRQCD heavy quark and D234 light quark actions. We employ constrained fits to extract ground state contributions to two- and three-point correlators. Results for the B --> pi, l nubar decay form factors are compared with previous lattice results. We find that our systematic errors (excluding quenching errors) are dominated by chiral extrapolation uncertainties.