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QCD2 ’t Hooft model: Two-flavor mesons spectrum

Aleksandr Artemev1,2,*, Alexey Litvinov1,†, and Pavel Meshcheriakov1,2,3,‡

  • *Contact author: artemev.aa@phystech.edu
  • †Contact author: A.Litvinov@skoltech.ru
  • ‡Contact author: meshcheriakov.pa@phystech.edu
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Phys. Rev. D 111, 125001 – Published 3 June, 2025

DOI: https://doi.org/10.1103/7311-kdbj

Abstract

We continue analytical study of the meson mass spectrum in the large-Nc two-dimensional QCD, known as the ’t Hooft model, by addressing the most general case of quarks with unequal masses. Based on our previous work, we develop nonperturbative methods to compute spectral sums and systematically derive large-n WKB expansion of the spectrum. Furthermore, we examine the behavior of these results in various asymptotic regimes, including the chiral, heavy quark, and heavy-light limits, and establish a precise coincidence with known analytical and numerical results obtained through alternative approaches.

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Phys. Rev. D 111, 125001– Published 3 June, 2025
  • Received 22 April 2025
  • Accepted 12 May 2025
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