Pion electric polarizability from lattice QCD

TL;DR

This paper uses lattice QCD with the background field method to compute the electric polarizability of pions at light quark masses, providing theoretical insights to complement upcoming experimental measurements.

Contribution

It presents the first lattice QCD calculations of pion electric polarizability at very light quark masses, bridging the gap between theory and experiment.

Findings

Electric polarizability values obtained at two light quark masses.

Results are consistent with chiral perturbation theory predictions.

Provides the lightest quark mass calculations for pion polarizability to date.

Abstract

Electromagnetic polarizabilities are important parameters for understanding the interaction between photons and hadrons. For pions these quantities are poorly constrained experimentally since they can only be measured indirectly. New experiments at CERN and Jefferson Lab are planned that will measure the polarizabilities more precisely. Lattice QCD can be used to compute these quantities directly in terms of quark and gluons degrees of freedom, using the background field method. We present results for the electric polarizability for two different quark masses, light enough to connect to chiral perturbation theory. These are currently the lightest quark masses used in polarizability studies.