Meson spectrum in the large $N$ limit

TL;DR

This study computes the lowest meson masses in SU(N) gauge theory at large N using lattice methods, confirming proper scaling across multiple lattice spacings and N values, and providing detailed results on meson spectra and decay constants.

Contribution

It presents the first-principles lattice calculation of meson spectra in the large N limit, including multiple N values and lattice spacings, with comprehensive error analysis and methodological validation.

Findings

Meson masses scale properly with lattice spacing.

Results are consistent across N=169, 289, 361.

Provides detailed meson spectrum and decay constants at large N.

Abstract

We present the result of our computation of the lowest lying meson masses for SU(N) gauge theory in the large $N$ limit (with $N_f/N\longrightarrow 0$). The final values are given in units of the square root of the string tension, and with errors which account for both statistical and systematic errors. By using 4 different values of the lattice spacing we have seen that our results scale properly. We have studied various values of $N$ (169, 289 and 361) to monitor the N-dependence of the most sensitive quantities. Our methodology is based upon a first principles approach (lattice gauge theory) combined with large $N$ volume independence. We employed both Wilson fermions and twisted mass fermions with maximal twist. In addition to masses in the pseudoscalar, vector, scalar and axial vector channels, we also give results on the pseudoscalar decay constant and various remormalization factors.