Abstract
In the Standard Model the three charged leptons are identical copies of each other, apart from mass differences, and the electroweak coupling of the gauge bosons to leptons is expected to be independent of the flavour. This prediction is called lepton flavour universality (LFU) and is well tested in tree-level decays; any violation of LFU would be a clear sign of physics beyond the Standard Model. Experimental tests of LFU in semileptonic decays of b hadrons and in rare b decays are highly sensitive to models of New Physics in which new, heavy particles couple preferentially to the 2nd and 3rd generations of leptons. Recent results from LHCb on LFU in semileptonic transitions and rare decays are discussed.
Highlights
‣ Forward spectrometer optimised for heavy flavour physics at the LHC: - Acceptance of 2 < η < 5 - Large boost: B mesons fly ~ 1 cm
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Summary
Annarita Buonaura on behalf of the LHCb collaboration University of Zurich 22 August 2018. XIIth International Workshop on the Interconnection between Particle Physics and Cosmology. ‣ Introduction - What is lepton flavour universality - Tests of lepton flavour universality - The LHCb detector. ‣ Lepton flavour universality violation in b→sll decays - R(K) and R(K*) - The P5’ anomaly
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