B-->pi and B-->K transitions in standard and quenched chiral perturbation theory

TL;DR

This paper analyzes the impact of chiral logarithms on heavy-to-light meson transition form factors using chiral perturbation theory, highlighting uncertainties in lattice QCD approximations and providing coefficients for quenched chiral logs.

Contribution

It introduces a method to quantify uncertainties from quenched approximations and missing chiral logs in lattice QCD studies of B meson transitions.

Findings

Quantifies the size of uncertainties due to quenched approximation.

Provides coefficients for quenched chiral logs in B to pi/K transitions.

Assists in systematic error assessment for lattice QCD extrapolations.

Abstract

We study the effects of chiral logs on the heavy-->light pseudoscalar meson transition form factors by using standard and quenched chiral perturbation theory combined with the static heavy quark limit. The resulting expressions are used to indicate the size of uncertainties due to the use of the quenched approximation in the current lattice studies. They may also be used to assess the size of systematic uncertainties induced by missing chiral log terms in extrapolating toward the physical pion mass. We also provide the coefficient multiplying the quenched chiral log, which may be useful if the quenched lattice studies are performed with very light mesons.