Stealth dark matter spectrum using LapH and Irreps

TL;DR

This paper reports non-perturbative lattice calculations of the SU(4) stealth dark matter spectrum, employing advanced operator projection techniques to improve accuracy and explore the low-lying baryon states relevant for dark matter models.

Contribution

It introduces the use of LapH and irreducible representation projections to reduce excited state contamination in lattice calculations of stealth dark matter spectra.

Findings

Good agreement with previous spectra using improved methods

First spectrum of low-lying odd-parity baryons presented

Reduced statistical uncertainties in baryon mass determinations

Abstract

We present non-perturbative lattice calculations of the low-lying meson and baryon spectrum of the SU(4) gauge theory with fundamental fermion constituents. This theory is one instance of stealth dark matter, a class of strongly coupled theories, where the lowest mass stable baryon is the dark matter candidate. This work constitutes the first milestone in the program to study stealth dark matter self-interactions. Here, we focus on reducing excited state contamination in the single baryon channel by applying the Laplacian Heaviside method, as well as projecting our baryon operators onto the irreducible representations of the octahedral group. We compare our resulting spectrum to previous work involving Gaussian smeared non-projected operators and find good agreement with reduced statistical uncertainties. We also present the spectrum of the low-lying odd-parity baryons for the first time.