Seminarium "Teoria cząstek elementarnych i kosmologia"

I will review recent results from LHCb with emphasis on recent precise measurements of rare decays and tests of Lepton Flavour Universality (LFU) at LHCb. Any violation of LFU would be a clear sign of physics beyond the SM. I will mainly focus on flavour-changing b → sll transitions, which are exceptionally sensitive to NP effects and in particular to NP particles that are too massive to be directly produced at present colliders. These particles can appear as virtual contributions that may induce significant effects on branching fractions and angular observables. In the last few years, hints of LFU violation have been observed, mainly by LHCb, in both loop-level b → sll and tree-level b → clν transitions. These measurements, combined with the tensions observed in angular observables and branching fractions of rare semileptonic b decays, have generated considerable interest in the community and, if confirmed, open up interesting prospects for the future.

Link: https://meet.google.com/urv-ctmy-xhs