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arXiv · 2603.01583

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

Claudio Bonanno·Margarita García Pérez·Antonio González-Arroyo·Ken-Ichi Ishikawa·Masanori Okawa
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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 $N_{\scriptscriptstyle{\rm f}}/N\to 0$. 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.

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Claudio Bonanno, Margarita García Pérez, Antonio González-Arroyo, Ken-Ichi Ishikawa, Masanori Okawa. 2026-03-02. Meson spectrum and low-energy constants in large-$N$ QCD. https://arxiv.org/abs/2603.01583

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