Possible indications of new physics in Bd-mixing and in sin(2β) determinations

AbstractUsing the hadronic matrix elements from the lattice, BK and ξs, involving only the 4-quark operators for Δ flavor=2 Hamiltonian relevant for K–K¯, Bd–B¯d and Bs–B¯s mixing, along with Vcb, we deduce a non-trivial constraint on the SM, sin(2β)=0.87±0.09. This deviates from direct experimental measurements via the tree process, b→cc¯s as well as the one via the penguin-loop b→s decays by around 2.1 and 2.7σ respectively. If these deviations are confirmed they would imply the presence of new physics rather pervasively in both Bd–B¯d (i.e. very likely in b→d) as well as in b→s transitions requiring a beyond the SM CP-odd phase. Consequently, improvements in the relevant lattice calculations should be given a high priority