Comptes Rendus
CP violation in B decays
Comptes Rendus. Physique, Volume 21 (2020) no. 1, pp. 61-74.

The experimental study of CP violation in B decays has led to significant progress in our understanding of nature: (i) It demonstrated that the Kobayashi-Maskawa mechanism is the dominant source of CP violation in meson decays. (ii) It improved significantly the precision in the determination of the parameters of the Cabibbo–Kobayashi–Maskawa quark-mixing matrix. (iii) It proved that new physics that has order-one flavour-changing couplings to the b quark should be characterised by a mass scale higher than 𝒪(10 3 TeV). Further progress is expected from the Belle II and LHC experiments during the next decade and beyond. Present status and perspectives are here discussed.

L’étude expérimentale de la brisure de la symétrie CP dans les désintégrations de mésons beaux (B) a apporté des contributions majeures à notre compréhension de la nature  : (i) Elle a établi que le mécanisme de Kobayashi-Maskawa est la source dominante de brisure de la symétrie CP dans les systèmes des mésons K et B. (ii) Elle a amélioré significativement la précision des paramètres qui décrivent la matrice de mélange des quarks Cabibbo–Kobayashi–Maskawa. (iii) Elle a prouvé que l’échelle d’énergie d’une nouvelle physique avec des couplages de changement de saveurs d’ordre unité, devait être supérieure à 𝒪(10 3 TeV). Des progrès sont attendus, dans cette décennie et la suivante, des expériences du LHC et Belle II. L’état de l’art de cette Physique et les perspectives des expériences futures sont discutés dans cet article.

Published online:
DOI: 10.5802/crphys.11
Keywords: Meson, Decay, LHC, Large Hadron Collider, CP symmetry violation
Mot clés : Méson, Désintégration, LHC, Grand collisionneur de hadrons, Violation de symétrie CP

Yosef Nir 1; Vincenzo Vagnoni 2

1 Weizmann Institute, Department of Particle Physics and Astrophysics, Rehovot 7610001, Israel
2 Istituto Nazionale di Fisica Nucleare, Sezione di Bologna, Italy
License: CC-BY 4.0
Copyrights: The authors retain unrestricted copyrights and publishing rights
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Yosef Nir; Vincenzo Vagnoni. $C{\hspace{-1.69998pt}}P$ violation in $B$ decays. Comptes Rendus. Physique, Volume 21 (2020) no. 1, pp. 61-74. doi : 10.5802/crphys.11. https://comptes-rendus.academie-sciences.fr/physique/articles/10.5802/crphys.11/

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