New Directions in Kaon Physics

Abstract

Recent measurements of kaon decays provide new information about CKM unitarity, lepton universality, and discrete symmetries. KLOE-2, the proposed extension of the kaon physics program at Frascati, will extend the world data set on kaon decays and conduct interference measurements with neutral kaons. Meanwhile, the decays K → πν ν can be directly related to the CKM matrix elements with minimal theoretical uncertainty, and are the focus of a series of experiments. Several events of K + → π + ν ν have been observed to date; the goal of the NA62 experiment at CERN is to perform an O(100)-event measurement in this channel. Initiatives in Japan-the E391a experiment at KEK, to become E14 at J-PARC-are focused on collecting a few K L → π 0 ν ν events in a first step, while working towards an O(100)-event measurement. Experiments capable of performing O(1000)-event measurements in both channels have been discussed.