KL →πγγ in KOTO experiment at JPARC
Jay Lin1*, Yee Bob Hsiung1
1Physics, National Taiwan University, Taipei, Taiwan
* presenting author:Jay Lin, email:jay@hep1.phys.ntu.edu.tw
KL → π⁰γγ has been predicted by O(6) calculation in chiral perturbation theory that includes vector meson exchange contribution. This decay mode is also important for the determination of the direct CP violation amplitude of KL → π⁰l+l-. Fermilab E832 and Cern NA48 have measured the branching ratio and pole parameter αV around 1.3Χ10-6 and -0.4 respectively. With a higher resolution in the calorimeter and efficiency of photon vetoes in KOTO experiment at JPARC, we expect to get a more precise measurement in both branching ratio and αV

Keywords: KOTO, ChPT, rare decay