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arXiv · 2408.15525

Study of CP Violation in charm decays

Felipe Cesário Laterza Lopes·Patrícia Camargo Magalhães
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Abstract

The violation of the Charge-Parity (CP) symmetry is a phenomenon described by the Standard Model (SM), however, its predictions for this violation are not enough to explain the matter-antimatter asymmetry in the visible universe. Experimentally, CP violation in hadronic decays had already been observed in various circumstances before 2019, when the LHCb experiment at CERN first published results reporting CPV in D-meson decays [arXiv:1903.08726v2] ($D^0 \to K^- K^+$ and $D^0 \to \pi^- \pi^+$). In this work, a study of CP violation is carried out analysing the phenomenology of charm decays. The study of such topic is guided by the Cabibbo-Kobayashi-Maskawa (CKM) matrix and the process of flavour changing decays caused by the weak interaction (focusing on charm decays). The symmetries attributed to physical conservation laws were recognized, allowing for the possibilities of CP violation predicted by the SM to be examined more closely. Such theoretical studies are then compared to the results obtained by the LHCb Collaboration. Furthermore, a comparison between CPV in charm decays and in neutrino oscillations is made, analysing the CP violating phase in both the CKM and the Pontecorvo-Maki-Nakagawa-Sakata (PMNS) matrices.

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Felipe Cesário Laterza Lopes, Patrícia Camargo Magalhães. 2024-08-28. Study of CP Violation in charm decays. https://arxiv.org/abs/2408.15525

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