Pion Decay Constant, $Z_A$ and Chiral Log from Overlap Fermions

TL;DR

This paper presents a lattice QCD calculation of the pion decay constant, axial renormalization constant, and chiral logarithms using overlap fermions on a quenched lattice, providing insights into chiral symmetry breaking.

Contribution

It introduces a calculation of key chiral parameters using overlap fermions on a quenched lattice, highlighting the effects of chiral logs and renormalization.

Findings

Calculated $f_$ and $Z_A$ with overlap fermions

Observed quenched chiral logarithms at pion masses down to 280 MeV

Demonstrated the effectiveness of overlap fermions in chiral studies

Abstract

We report our calculation of the pion decay constant $f_\pi$, the axial renormalization constant $Z_A$, and the quenched chiral logarithms from the overlap fermions. The calculation is done on a quenched $20^4$ lattice at $a=0.148$ fm using tree level tadpole improved gauge action. The smallest pion mass we reach is about 280 MeV. The lattice size is about 4 times the Compton wavelength of the lowest mass pion.