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arXiv · 2504.12081

QCD$_2$ 't Hooft model: 2-flavour mesons spectrum

Aleksandr Artemev·Alexey Litvinov·Pavel Meshcheriakov
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Abstract

We continue analytical study of the meson mass spectrum in the large-$N_c$ 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 non-perturbative 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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Aleksandr Artemev, Alexey Litvinov, Pavel Meshcheriakov. 2025-04-16. QCD$_2$ 't Hooft model: 2-flavour mesons spectrum. https://arxiv.org/abs/2504.12081

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