The Time Reversal Experiment with Kaons (TREK) at J‐PARC

The Time Reversal Experiment with Kaons (TREK) at J‐PARC aims to find CP violation beyond the Standard Model in the semi‐leptonic $Kμ3+$ decay mode by measuring the T‐violating transverse polarization $PT$ of outgoing muons. TREK makes use of the intense kaon beam at J‐PARC stopped in a target and employs an optimized setup with excellent control of systematic uncertainties. The sensitivity at J‐PARC is improved by a factor of 20 compared to the current uncertainty for $PT,$ well in the predicted range of various New Physics models. An overview of the planned experiment and current status will be presented.