Hamiltonian effective field theory study of the $\mathbf{N^*(1535)}$ resonance in lattice QCD

TL;DR

This paper uses Hamiltonian effective field theory to predict and analyze the finite-volume energy levels of the N*(1535) resonance in lattice QCD, bridging experimental data and lattice results.

Contribution

It introduces a Hamiltonian effective field theory approach constrained by experiment to predict lattice QCD energy levels and extract resonance properties.

Findings

Excellent agreement between HEFT predictions and lattice QCD results.

Lattice data can constrain low-energy coefficients to determine resonance properties.

Analysis highlights the importance of different Hamiltonian components.

Abstract

Drawing on experimental data for baryon resonances, Hamiltonian effective field theory (HEFT) is used to predict the positions of the finite-volume energy levels to be observed in lattice QCD simulations of the lowest-lying $J^P=1/2^-$ nucleon excitation. In the initial analysis, the phenomenological parameters of the Hamiltonian model are constrained by experiment and the finite-volume eigenstate energies are a prediction of the model. The agreement between HEFT predictions and lattice QCD results obtained on volumes with spatial lengths of 2 and 3 fm is excellent. These lattice results also admit a more conventional analysis where the low-energy coefficients are constrained by lattice QCD results, enabling a determination of resonance properties from lattice QCD itself. Finally, the role and importance of various components of the Hamiltonian model are examined.