اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدNew Physics in Flavour Observables
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تأليف
Andreas Crivellin
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LHCb found hints for physics beyond the Standard Model (SM) in $Bto K^*mu^+mu^-$, $R(K)$ and $B_stophimu^+mu^-$. These intriguing hints for NP have recently been confirmed by the LHCb measurement of $R(K^*)$ giving a combined significance for NP above the $5,sigma$ level. In addition, the BABAR, BELLE and LHCb results for $Bto D^{(*)}tau u$ also point towards lepton flavour universality (LFU) violating new physics (NP). Furthermore, there is the long-standing discrepancy between the measurement and the theory prediction of the anomalous magnetic moment of the muon ($a_mu$) at the $3,sigma$ level. Concerning NP effects, $bto smu^+mu^-$ data can be naturally explained with a new neutral gauge bosons, i.e. a $Z^prime$ but also with heavy new scalars and fermions contributing via box diagrams. Another promising solution to $bto smu^+mu^-$, which can also explain $Bto D^{(*)}tau u$, are leptoquarks. Interestingly, leptoquarks provide also a viable explanation of $a_mu$ which can be tested via correlated effects in $Ztomu^+mu^-$ at future colliders. Considering leptoquark models, we show that an explanation of $Bto D^{(*)}tau u$ predicts an enhancement of $bto stau^+tau^-$ processes by around three orders of magnitude compared to the SM. In case of a simultaneous explanation of $Bto D^{(*)}tau u$ and $bto smu^+mu^-$ data, sizable effects in $bto staumu$ processes are predicted.
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