Heavy light decay constants on the lattice

TL;DR

This paper reports lattice QCD calculations of heavy-light meson decay constants, including preliminary results for f_Ds with dynamical fermions, and discusses systematic effects in extrapolations from charm to bottom quarks.

Contribution

It provides new lattice QCD results for heavy-light decay constants with dynamical fermions and analyzes the systematic uncertainties in quark mass extrapolations.

Findings

No significant difference between f_Ds with Nf=2 and Nf=0.

Extrapolation from charm to bottom quark mass is under control.

Preliminary results for f_Ds with dynamical fermions are presented.

Abstract

We present results for the leptonic decays of heavy-light mesons in the quenched approximation and a preliminary result for f_Ds with dynamical fermions for Nf=2. We examine the systematic effects of extrapolating the decay constants from the charm to the bottom quark mass, and find this extrapolation to be under control. We present a preliminary result for f_Ds{Nf=2} and compare to f_Ds{Nf=0} matched to have the same lattice spacing set by the Sommer scale, r0. We find no significant difference.