Meson spectrum and low-energy constants in large-$N$ QCD

Abstract

We present new non-perturbative results about the meson spectrum and the low-energy constants of QCD in the 't Hooft large-$N$ limit, $N\to \infty$ with $N_{\mathrm{f}}/N\to 0$. These are obtained from lattice Monte Carlo simulations of the Twisted Eguchi-Kawai (TEK) model up to $N=841$. More precisely, we will discuss: our findings for the meson mass spectrum; the determination of the radial Regge trajectories in the $\pi$ and $\rho$ channels; the computation of the coefficients of the $1/N$ expansion of the chiral condensate, of the pion decay constant, and of the next-to-leading-order coupling ${\bar{\ell }}_4$, up to $\mathcal{O}(1/N^3)$ from the combination of TEK and standard finite-$N$ results.

Comments: 10 pages, 3 figures, Contribution to the 42nd International Symposium on Lattice Field Theory (LATTICE2025), 2-8 Nov. 2025, Mumbai, India