Malgré la solidité du modèle standard de la physique des particules, il a y de bonnes raisons de penser que ce n'est pas la théorie « ultime ». En particulier, le modèle standard ne peut expliquer, ni la matière noire, ni l'asymétrie matière–antimatière dans l'Univers. LHCb est un spectromètre du LHC (Large Hadron Collider) consacré à des mesures de précision des particules de saveurs lourdes. Comme des particules de nouvelle physique peuvent contribuer de manière virtuelle aux désintégrations de particules de saveurs lourdes et ainsi modifier leurs propriétés, de telles mesures sont sensibles à des masses bien plus élevées que celles accessibles grâce aux mesures directes. Dans le présent article, nous expliquons comment la présence de particules nouvelles peut être détectée en testant l'universalité du couplage aux leptons dans les désintégrations de hadrons contenant un quark b.
Despite the enduring resilience of the Standard Model of particle physics, there remain reasons to expect that it is not a “final” theory. In particular, the Standard Model can not explain either dark matter or the observed matter–antimatter asymmetry of the universe. LHCb is a forward acceptance spectrometer at the Large Hadron Collider, dedicated to precision measurements of heavy flavour particles. Because new particles can appear virtually in the decays of heavy flavour particles, and thus alter their properties, such measurements are inherently sensitive to much higher mass scales that direct searches. We present in this article how the presence of new particles can be probed by testing Lepton Universality in the decay of hadrons containing a b-quark.
Mot clés : LHCb, Modèle standard, Recherche indirecte
Yasmine Amhis 1
@article{CRPHYS_2017__18_5-6_358_0, author = {Yasmine Amhis}, title = {On the universality (or not) of beautiful penguins}, journal = {Comptes Rendus. Physique}, pages = {358--364}, publisher = {Elsevier}, volume = {18}, number = {5-6}, year = {2017}, doi = {10.1016/j.crhy.2017.09.010}, language = {en}, }
Yasmine Amhis. On the universality (or not) of beautiful penguins. Comptes Rendus. Physique, Volume 18 (2017) no. 5-6, pp. 358-364. doi : 10.1016/j.crhy.2017.09.010. https://comptes-rendus.academie-sciences.fr/physique/articles/10.1016/j.crhy.2017.09.010/
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