Lepton flavor violation in little higgs models

Abstract

We report on our study of the LFV processes μ → eγ, μ → eee and μN → eN in the context of Little Higgs models. Specifically, we examine the Littlest Higgs with T-parity (LHT) and the Simplest Little Higgs (SLH) as examples of a Product group and Simple group Little Higgs models, respectively. The necessary Feynman rules for both models are obtained in the ’t Hooft Feynman Gauge up to the order of v2 / f2 and predictions for the branching ratios and conversion rates of the LFV processes are calculated to leading order (one-loop level). Comparison with current experimental constraints show that there is some tension and, in order to be within the limits, one requires a higher breaking scale f, alignment of the heavy and light lepton sectors or almost degenerate heavy lepton masses. These constraints are more demanding in the SLH than in the LHT case.