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arXiv · 2412.13800

$e^+ e^- \to \mu^+ \mu^-$ in the Asymptotically Safe Standard Model

Álvaro Pastor-Gutiérrez·Jan M. Pawlowski·Manuel Reichert·Giacomo Ruisi
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Abstract

We study the electron-positron to muon--anti-muon cross-section in the asymptotically safe Standard Model. In particular, we include the graviton contributions to the scattering amplitude, which is computed from momentum-dependent timelike one-particle-irreducible correlation functions. Specifically, we employ reconstruction techniques for the graviton spectral functions. We find that the full asymptotically safe quantum cross section decreases in the ultraviolet with the centre-of-mass energy, and is compatible with unitarity bounds. Importantly, our findings provide non-trivial evidence for the unitarity of the asymptotically safe Standard Model.

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Álvaro Pastor-Gutiérrez, Jan M. Pawlowski, Manuel Reichert, Giacomo Ruisi. 2024-12-18. $e^+ e^- \to \mu^+ \mu^-$ in the Asymptotically Safe Standard Model. https://doi.org/10.1103/physrevd.111.106005

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