Baryon Operators and Baryon Spectroscopy

TL;DR

This paper discusses methods for determining the baryon resonance spectrum in lattice QCD, emphasizing the importance of operator construction and smearing techniques for accurate spectroscopy.

Contribution

It introduces a variational method and group-theory-based construction of baryon operators, highlighting the role of smearing in improving spectral analysis.

Findings

Smearing reduces high-frequency mode coupling.

Smearing decreases gauge-field fluctuations.

Current investigations are progressing in baryon spectroscopy.

Abstract

The issues involved in a determination of the baryon resonance spectrum in lattice QCD are discussed. The variational method is introduced and the need to construct a sufficient basis of interpolating operators is emphasised. The construction of baryon operators using group-theory techniques is outlined. We find that the use both of quark-field smearing and link-field smearing in the operators is essential firstly to reduce the coupling of operators to high-frequency modes and secondly to reduce the gauge-field fluctuations in correlators. We conclude with a status report of our current investigation of baryon spectroscopy.