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arXiv · 2610.03183

Looking at radiative corrections to the $Σ^\pm\toΛe^\pm \barν$ semileptonic decay-rate ratio

Constantia Alexandrou·Simone Bacchio·Antonio Evangelista·Andreas Konstantinou·Nazario Tantalo
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Abstract

We investigate the impact of radiative corrections on the ratio of the semileptonic decay rates $Σ^\pm\toΛe^\pm \barν$. Phenomenological analyses point to sizable radiative effects on the experimentally measured ratio. From a theoretical perspective, this observable is particularly appealing because several hadronic and electroweak contributions partially cancel in the ratio, providing a cleaner probe of electromagnetic effects. We identify the dominant contributions to the radiative corrections and develop the framework for a dedicated calculation. This represents a first step toward a precise theoretical description of baryon semileptonic decays, helping to assess their potential as precision tests of the Standard Model.

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Constantia Alexandrou, Simone Bacchio, Antonio Evangelista, Andreas Konstantinou, Nazario Tantalo. 2026-10-02. Looking at radiative corrections to the $Σ^\pm\toΛe^\pm \barν$ semileptonic decay-rate ratio. https://arxiv.org/abs/2610.03183

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