We review how the muon anomalous magnetic moment (g − 2) and the quest for lepton flavor violation are intimately correlated. Indeed the decay µ → eγ is induced by the same amplitude for different choices of in-and outgoing leptons. In this work, we try to address some intriguing questions such as:Which hierarchy in the charged lepton sector one should have in order to reconcile possible signals coming simultaneously from g − 2 and lepton flavor violation?What can we learn if the g − 2 anomaly is confirmed by the upcoming flagship experiments at FERMILAB and J-PARC, and no signal is seen in the decay µ → eγ in the foreseeable future? On the other hand, if the µ → eγ decay is seen in the upcoming years, do we need to necessarily observe a signal also in g − 2?.In this attempt, we generally study the correlation between these observables in a detailed analysis of simplified models. We derive master integrals and

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The scotogenic model proposed by Ernest Ma represents an attractive and minimal example for the generation of small Standard Model neutrino masses via radiative corrections in the dark matter sector. In this paper, we demonstrate that, in addition to neutrino masses and dark matter, the scotogenic model also allows to explain the baryon asymmetry of the Universe via low-scale leptogenesis. First, we consider the case of two right-handed neutrinos (RHNs) N 1;2 , for which we provide an analytical argument why it is impossible to push the RHN mass scale below M min 1 ∼ 10 10 GeV, which is identical to the value in standard thermal leptogenesis in the type-I seesaw scenario with the same washout strength. Then, we present a detailed study of the three-RHN case based on both an analytical and a numerical analysis. In the case of three RHNs, we obtain a lower bound on the N 1 mass of around 10 TeV. Remarkably enough, successful low-scale leptogenesis can be achieved without any degeneracy in the RHN mass spectrum. The only necessary condition is a suppression in the N 1 Yukawa couplings, which results in suppressed washout and a small active neutrino mass of around 10 −12 eV. This leads to the fascinating realization that low-scale leptogenesis in the scotogenic model can be tested in experiments that aim at measuring the absolute neutrino mass scale.

Abstract:The scotogenic scenario provides an attractive approach to both Dark Matter and neutrino mass generation, in which the same symmetry that stabilises Dark Matter also ensures the radiative seesaw origin of neutrino mass. However the simplest scenario may suffer from inconsistencies arising from the spontaneous breaking of the underlying Z 2 symmetry. Here we show that the singlet-triplet extension of the simplest model naturally avoids this problem due to the presence of scalar triplets neutral under the Z 2 which affect the evolution of the couplings in the scalar sector. The scenario offers good prospects for direct WIMP Dark Matter detection through the nuclear recoil method.