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arXiv · 2105.00923

$U(1)_A$ axial anomaly, $\eta^\prime$, and topological susceptibility in the holographic soft-wall model

Floriana Giannuzzi·Stefano Nicotri
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Abstract

The singlet pseudoscalar sector of light mesons is investigated in the soft-wall model, a bottom-up approach to the AdS/QCD correspondence. The $\eta^\prime$ mass results from the mixing among the fields dual to the axial current, pseudoscalar current and the $G\tilde G$ operator. The topological susceptibility is computed for any quark mass, and the Witten-Veneziano relation is obtained in the large $N_c$ limit.

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Floriana Giannuzzi, Stefano Nicotri. 2021-05-03. $U(1)_A$ axial anomaly, $\eta^\prime$, and topological susceptibility in the holographic soft-wall model. https://doi.org/10.1103/physrevd.104.014021

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