ϕ1/β Determination

Measurements of time-dependent CP asymmetries in B0→J/ψK0 and related b→c transitions provide precise measurements of sin 2ϕ1. Time-dependent CP asymmetries in B0→ϕK0 and related b→s FCNC transitions also give sin 2ϕ1 to a good approximation within the Standard Model. Deviations from the Standard Model expectations would indicate a new source of CP violation. In this article, the present experimental results, as well as prospects for discoveries at LHC experiments and at SuperKEKB are summarized. In the end, several questions for discussions are raised.