mu-e conversion with four generations

作者：Deshpande, N. G.; Enkhbat, T.; Fukuyama, T.; He, X. -G.^*; Tsai, L. -H.; Tsumura, K.

来源：Physics Letters B, 2011, 703(5): 562-566.

DOI：10.1016/j.physletb.2011.08.045

• 4TH GENERATION
• CP-VIOLATION
• WEAK-INTERACTIONS
• SEARCH
• FAMILY
• MODEL
• NONCONSERVATION
• ELECTRON
• LIMIT

We study mu-e conversion with sequential four generations. A large mass for the fourth generation neutrino can enhance the conversion rate by orders of magnitude. We compare constraints obtained from mu-e conversion using experimental bounds on various nuclei with those from mu -> e gamma and mu -> e(e) over bar e. We find that the current bound from mu-e conversion with Au puts the most stringent constraint in this model. The relevant flavor changing parameter lambda(mu e) = V*V-mu 4(e4) is constrained to be less than 1.6 x 10(-5) for the fourth generation neutrino mass larger than 100 GeV. Implications for future mu-e conversion, mu -> e gamma and mu -> e(e) over bar e experiments are discussed.

• 出版日期2011-9-26
• 单位上海交通大学