Electromagnetic pion mass splitting using PV-regulated photon propagator
Abstract
Several hadronic observables are nowadays computed in lattice QCD with a sub-percent precision which requires the inclusion of strong isospin-breaking and electromagnetic effects. Most of the methods that implement the photon propagator in finite-volume lead to power-law suppressed finite-size effects and do not allow for a straightforward crosscheck against phenomenology and other calculations. Both issues can be avoided by working with a Pauli-Villars regulated photon propagator defined directly in the continuum and infinite volume. This methodology can be profitably exploited to improve the determination of leading-order electromagnetic corrections to several observables such as the HVP or nucleon masses. In this work we apply the strategy to the charged/neutral pion mass difference using CLS ensembles.
Cite
@article{arxiv.2603.10496,
title = {Electromagnetic pion mass splitting using PV-regulated photon propagator},
author = {Alessandro De Santis and Dominik Erb and Harvey B. Meyer},
journal= {arXiv preprint arXiv:2603.10496},
year = {2026}
}
Comments
Contribution to the 42nd International Symposium on Lattice Field Theory (LATTICE2025), 2-8 November 2025, Tata Institute of Fundamental Research, Mumbai, India