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arXiv · 2203.13454

Measuring CP violation in rare $W$ decays at the LHC

Peng-Cheng Lu·Zong-Guo Si·Zhe Wang·Xing-Hua Yang
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Abstract

Heavy Majorana neutrinos beyond the standard model can simultaneously explain the origin of tiny neutrino masses and matter-antimatter asymmetry in our Universe. The existence of heavy Majorana neutrinos will also lead to lepton number violation and the rare lepton-number-violating $W$ decays are possible. With contributions from two different Majorana neutrinos, a nonzero CP asymmetry may be generated from the rate difference between $W$ decay and its CP-conjugate process. The aim of this paper is to investigate the prospects for measuring CP violation in rare $W$ decays via Majorana neutrinos at the LHC. Our calculations show that the induced CP asymmetry is independent of the Majorana neutrino mass for $10~ \rm GeV < m_N < 70 ~\rm GeV$. Such a CP asymmetry if observed, would in turn provide unambiguous evidence of new physics beyond the standard model.

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Peng-Cheng Lu, Zong-Guo Si, Zhe Wang, Xing-Hua Yang. 2022-03-25. Measuring CP violation in rare $W$ decays at the LHC. https://doi.org/10.1088/1674-1137/ac7eb2

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