The charm quark mass with dynamical fermions

TL;DR

This paper calculates the charm quark mass using lattice QCD with dynamical fermions, comparing different formulations and quenched data to assess the effects of sea quarks and continuum extrapolation.

Contribution

It provides a comparison of heavy quark formulations and quenched versus dynamical data, highlighting their continuum limits and potential overestimation of charm quark mass.

Findings

Different formulations converge to the same continuum limit in quenched approximation.

Limited evidence suggests quenched approximation overestimates charm quark mass.

Comparison between quenched and dynamical results informs about sea quark effects.

Abstract

We compute the charm quark mass in lattice QCD and compare different formulations of the heavy quark, and quenched data to that with dynamical sea quarks. We take the continuum limit of the quenched data by extrapolating from three different lattice spacings, and compare to data with two flavours of dynamical sea quarks with a mass around the strange at the coarsest lattice spacing. Both the FNAL and ALPHA formalism are used. We find the different heavy quark formulations have the same continuum limit in the quenched approximation, and limited evidence that this approximation overestimates the charm quark mass.