$CP$-violation and $U$-spin symmetry in four-body bottom baryon decays

Shibasis Roy

doi:10.1016/j.physletb.2025.139838

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arXiv · 2504.10891

$CP$-violation and $U$-spin symmetry in four-body bottom baryon decays

Shibasis Roy

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Abstract

In view of the recent observation of $CP$-violation in bottom baryon decays, we explore $CP$-asymmetry relations in charmless four-body decays of bottom baryons featuring fully charged hadronic final states. Starting with a general effective Hamiltonian, we derive amplitude relations among various decay modes within the framework of $U$-spin symmetry. These relations lead to symmetry-based predictions for $CP$-violating rate asymmetries in $U$-spin conjugate decay channels. Furthermore, we demonstrate that all leading-order amplitude relations are violated once $U$-spin breaking effects are taken into account.

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Shibasis Roy. 2025-04-15. $CP$-violation and $U$-spin symmetry in four-body bottom baryon decays. https://doi.org/10.1016/j.physletb.2025.139838

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