Lepton non-universality in B to tau decays?

by Dr Greg Ciezarek

Previous measurements of the B -> D(*) tau nu branching fractions exceed the Standard Model expectations by more than three sigma. These decays are sensitive to new physics contributions which are relatively unconstrained by other processes. I present a new measurement of the B -> D* tau nu branching fraction at LHCb, the first measurement of any B -> tau X process at a hadron collider.