Matrix elements of bound states in a finite volume

TL;DR

This paper discusses a formalism for extracting infinite volume form factors of bound states from finite volume lattice QCD calculations, with a focus on the deuteron, highlighting the importance of the full formalism to control systematics.

Contribution

It applies a recent finite volume formalism to bound states like the deuteron, emphasizing the need for the complete approach to accurately determine form factors.

Findings

Finite volume effects can significantly impact bound state form factors.

The full formalism is necessary to avoid systematic errors in lattice QCD studies.

Application to the deuteron demonstrates the formalism's relevance for nuclear physics.

Abstract

Recently, a framework was developed for studying form factors of two-body states probed with an external current. Finite volume matrix elements that may be computed via lattice QCD are converted to infinite volume generalized form factors. These generalized form factors allow us to study the structure of composite states. In this talk, we consider the application of this formalism to bound states, and compare the leading finite volume effects to the general results of the framework. Specifically, we consider the implications for the deuteron at the physical point, and conclude that it's necessary to use the full formalism to not be saturated by systematics