报告题目:(g−2)_{mu}Versus Flavor Changing Neutral Current Induced by the Light (B−L)_{mu tau}Boson
报告人:Dr. YoshihiroShigekami
工作单位:华中科技尊龙凯时
报告时间: 2019年11月28日15:00
报告地点:中心校区物理楼333报告厅
摘要:
Wepropose the local (B−L)_{mu tau} model, which minimally retains the local B−Lextension for the sake of neutrino phenomenologies, and at the same timepresents an invisible gauge boson Z' with mass of O(10) MeV to account for thediscrepancy of the muon anomalous magnetic moment. However, to accommodate thecorrect pattern of Cabibbo-Kobayashi-Maskawa matrix, we have to introduceeither a SU(2)_L doublet flavon or vector-like quarks plus a singlet flavon. Ineither case Z' induces flavor changing neutral current (FCNC) in the quarksector at tree-level. We find that the former scheme cannot naturally suppressthe FCNC from the down-type quark sector and thus requires a large fine-tuningto avoid the stringent K --> pi nu nubar bound. Whereas the latter scheme,in which FCNC merely arises in the up-type quark sector, is still free ofstrong constraint. In particular, it opens a new window to test our scenario bysearching for flavor-changing top quark decay mode t --> u/c+(invisible),and the typical branching ratio is O(10^−4).
主办单位:尊龙凯时物理学院
尊龙凯时理论物理中心