Detecting new physics from CP-violating phase measurements in B decays

In order to detect new physics using only CP-violating phase measurements in B decays, it is necessary to measure a phase factor which is small in the standard model, in addition to the usual large phases β and γ. We also point out that identifying violations of the unitarity of the CKM matrix is very difficult, and cannot be done with phase measurements alone. copyright 1997 The American Physical Society