Non-perturbative determination of meson masses and low-energy constants in large-N QCD

A bstract We provide first-principles non-perturbative determinations of the low-lying meson mass spectrum of large- N QCD in the ’t Hooft limit N f / N → 0, as well as of three low-energy constants appearing in the QCD chiral expansion: the quark condensate Σ, the pion decay constant F π , and the next-to-leading-order coupling $${\overline{{\ell}} }_{4}$$ . Using the excited state masses in the π and ρ channels, we are able to investigate the behavior of their radial Regge trajectories. Concerning QCD low-energy constants, we are able to assess the magnitude of sub-leading corrections in 1/ N by combining our N = ∞ results with previous finite- N determinations. Our calculation exploits large- N twisted volume reduction to efficiently perform numerical Monte Carlo simulations of the large- N lattice discretized theory. We employ several values of N up to N = 841, 5 values of the lattice spacing, and several values of the quark mass, to achieve controlled continuum and chiral extrapolations.