Challenges in Hadronic Form Factor Calculations

TL;DR

This paper introduces a new technique to improve the calculation of excited-state and high-momentum transfer form factors in lattice QCD, addressing longstanding challenges and providing more accurate theoretical inputs for experimental programs.

Contribution

The work presents a simple method to enhance signal extraction for excited states and large-$Q^2$ form factors in lattice calculations, applicable to both anisotropic and isotropic lattices.

Findings

Improved signals for excited-state quantities on anisotropic lattices.

Potential application of the technique to isotropic lattices for high-$Q^2$ form factors.

Addresses difficulties in extracting signals at large transfer momenta.

Abstract

There is an extensive history of form factor calculations on the lattice, primarily with ground states for both initial and final states. However, there have never been any radially excited transition form factor calculations. Furthermore, the lattice faces difficulty in extracting signal from noise at large transfer momenta ($Q^2$). These measurements could give important theoretical input to experiments, such as those of JLab's 12 GeV program and studies of deformation of the nucleon. In this work, I will present a simple technique to resolve both of these difficulties and present results from anisotropic configurations showing improved signals for excited-state quantities. It should also be possible to apply this technique to isotropic lattices for calculating large-$Q^2$ form factors.