# Light Quark Masses with an O(a)-Improved Action

## TL;DR

This paper reports on Fermilab's lattice QCD calculations of light quark masses using an improved action, providing a precise estimate within the quenched approximation.

## Contribution

It introduces a calculation of light quark masses employing tadpole-improved SW quarks and analyzes systematic errors for improved accuracy.

## Key findings

- Average light quark mass in quenched approximation: 3.6 ± 0.6 MeV
- Uses tadpole-improved Sheikholeslami-Wohlert (SW) quarks
- Systematic errors are thoroughly studied

## Abstract

We present the recent Fermilab calculations of the masses of the light quarks, using tadpole-improved Sheikholeslami-Wohlert (SW) quarks. Various sources of systematic errors are studied. Our final result for the average light quark mass in the quenched approximation evaluated in the $\bar{MS}$ scheme is $\bar{m}_q(\mu=2 GeV;n_f=0)= (m_u+m_d)/2=3.6 \pm 0.6 MeV$.