Kaon experiments at J-PARC

The newly constructed high-intensity proton synchrotron, J-PARC ( J apan P roton A ccelerator R esearch C omplex), has completed its first stage of construction and started accelerator commissioning. Many experiments using slowly extracted proton beam are proposed and being prepared. Among them, two experiments to study Kaon decays, KOTO to search for a K L → π 0 ν ν ¯ decay and TREK for violation of Time-Reversal invariance, are under preparation. In this article, current status of the experiments is reported.