Status of Θ 13

The Neutrino mixing angle θ 13 is at the focus of current neutrino research. Till 2010 the value of θ 13 was assumed to be zero. Thanks to a number of consistent experimental efforts now we have a definitive value of θ 13 . Its measured value is sin 2 2 θ 13 ≈ 0.1. This has promising implications for the determination of the two remaining unknown parameters, sign of the ∆ m 2 31 and CP violating phase δ CP from the present and proposed accelerator neutrino experiments in the foreseeable future.