KEK素粒子原子核研究所・理論セミナー(北原 鉄平氏)

開始2020/05/28 (木) 13:30
終了2020/05/28 (木) 14:30
会場Online (Zoom)
講演タイトルDirect CP violation in K→μ+μ−K→μ+μ− and new physics search
講演者北原 鉄平氏(名古屋大学)


A rare decay KL→μ+μ−KL→μ+μ− has been measured precisely, while a similar rare decay KS→μ+μ−KS→μ+μ− has not been seen yet, which will be measured by an upgrade of the LHCb experiment. Although both processes are almost CP conserving, I will point out that an interference contribution between KLKL and KSKS in a neutral kaon beam emerges from a genuine direct CP violation. It will be shown that the interference contribution can be a comparable size to the standard-model prediction of BR(KS→μ+μ−)(KS→μ+μ−). I will also introduce several new physics effects in K→μ+μ−K→μ+μ−, and a connection with ϵ′/ϵϵ′/ϵ, which is a direct CP violation in K→ππK→ππ. References: arXiv:1707.06999, Phys.Rev.Lett. 119 (2017) 20, 201802 arXiv:1711.11030, JHEP 05 (2018) 024 arXiv:1712.04959, JHEP 04 (2018) 019