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arXiv · 2110.05962

Scalar resonances in the hadronic light-by-light contribution to the muon $(g-2)$

Luigi Cappiello·Oscar Catà·Giancarlo D'Ambrosio
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Abstract

We evaluate the contribution of scalar mesons to the hadronic light-by-light piece of the muon anomalous magnetic moment, using a warped five-dimensional model and holographic methods. We assess the contribution of the lightest, sub-GeV scalars $\sigma(500)$, $a_0(980)$ and $f_0(980)$ together with their associated towers of excited states, which the model generates automatically. Our results point at a clearly negative contribution, overwhelmingly dominated by the $\sigma(500)$ meson, that we estimate at $a_\mu^{\rm{HLbL,S}}=-9(2)\cdot 10^{-11}$. This number is in very good agreement with the most recent determinations from dispersive analyses.

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Luigi Cappiello, Oscar Catà, Giancarlo D'Ambrosio. 2021-10-12. Scalar resonances in the hadronic light-by-light contribution to the muon $(g-2)$. https://doi.org/10.1103/physrevd.105.056020

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