Volume Effects on the Method of Extracting Form Factors at Zero Momentum

TL;DR

This paper examines finite volume effects in the Rome method for extracting form factors at zero momentum, using chiral perturbation theory to quantify these effects on the pion charge radius.

Contribution

It develops a framework to evaluate finite volume effects in zero-momentum form factor extraction methods, generalizable to other low-energy matrix elements.

Findings

Finite volume effects can significantly impact form factor calculations.

Chiral perturbation theory effectively estimates these effects.

Framework applicable to various low-energy physics studies.

Abstract

The Rome method allows one to extract form factors using lattice computations performed strictly at zero momentum. We investigate the size of finite volume effects resulting from this method. As a test case, we focus on the pion charge radius and show how to ascertain the finite volume effect with the aid of chiral perturbation theory. The framework developed can easily be generalized to account for modified infrared physics of other low-energy matrix elements extracted at zero momentum.