New Physics and Evidence for a Complex CKM

We carefully analyse the present experimental evidence for a com- plex CKM matrix, even allowing for New Physics contributions to ǫK, a J/�KS , �MBd , �MBs , and theI = 1/2 piece of B → ρρ and B → ρπ. We emphasize the crucial role played by the angle γ in both providing irrefutable evidence for a complex CKM matrix and placing constraints on the size of NP contributions. It is shown that even if one allows for New Physics a real CKM matrix is excluded at a 99.92% C.L., and the probability for the phase γ to be in the interval (−170 ◦ ; −10 ◦ ) ∪ (10 ◦ ;170 ◦ ) is 99.7%.