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arXiv · 2606.29885

The topological susceptibility slope $\chi^\prime$ in the large-$N$ limit

Claudio Bonanno
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Abstract

This paper presents the first non-perturbative lattice determination of the Yang--Mills topological susceptibility slope $\chi^\prime$ in the large-$N$ limit. This quantity represents the $\mathcal{O}(p^2)$ term of the momentum expansion of the topological charge density two-point correlator, and has important theoretical and phenomenological implications for strong interactions. This calculation is based on a novel algorithm that avoids topological freezing at large $N$ on fine lattices, and on a novel method to reliably compute $\chi^\prime$ on the lattice. The results of this study are relevant for the description of the proton spin in deep inelastic scattering experiments via the Shore--Veneziano formula.

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Claudio Bonanno. 2026-06-29. The topological susceptibility slope $\chi^\prime$ in the large-$N$ limit. https://arxiv.org/abs/2606.29885

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