Bayesian approach to the first excited nucleon state in lattice QCD

TL;DR

This paper applies the maximum entropy method to lattice QCD data to reconstruct the spectral function of nucleon states, revealing finite size effects on the first excited nucleon state.

Contribution

First attempt to use MEM for spectral function reconstruction in nucleon channels from lattice QCD data, highlighting finite size effects.

Findings

Finite size effects significantly impact the first excited nucleon state.

MEM enables access to excited state spectrum information.

Preliminary results demonstrate the method's potential.

Abstract

We present preliminary results from the first attempt to reconstruct the spectral function in the nucleon and $\Delta$ channels from lattice QCD data using the maximum entropy method (MEM). An advantage of the MEM analysis is to enable us to access information of the excited state spectrum. Performing simulations on two lattice volumes, we confirm the large finite size effect on the first excited nucleon state in the lighter quark mass region.