Finite-volume effects and the electromagnetic contributions to kaon and pion masses

Understand

We report on the MILC Collaboration calculation of electromagnetic effects on light pseudoscalar mesons.

• The simulations employ asqtad staggered dynamical quarks in QCD plus quenched photons, with lattice spacings varying from 0.12 to 0.06 fm.
• Finite volume corrections for the MILC realization of lattice electrodynamics have been calculated in chiral perturbation theory and applied to the lattice data.
• These corrections differ from those calculated by Hayakawa and Uno because our treatment of zero modes differs from theirs.