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  • Letter
  • Open Access

Meson states in the ‘t Hooft model: Hamiltonian approach

Andrei Smilga*

  • SUBATECH, Université de Nantes, 4 rue Alfred Kastler, BP 20722, Nantes 44307, France

  • *Contact author: smilga@subatech.in2p3.fr

Phys. Rev. D 114, L081702 – Published 20 October, 2026

DOI: https://doi.org/10.1103/n9c8-q7g3

Abstract

We point out that the masses of the highly excited bound quark-antiquark states in QCD2 in the infinite N limit may be determined in the framework of a simple quantum-mechanical model with the potential V(x)=σ|x|. In the ultrarelativistic case, the masses follow the pattern μn2=πg2N2n, which coincides with the law derived by ‘t Hooft by solving the Bethe-Salpeter equation. In the nonrelativistic case, the levels follow the asymptotics εn=μn−2m=Cn2/3, where the constant C can be determined by solving the ‘t Hooft equation or, alternatively, the nonrelativistic Schrödinger equation.

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