An explanation for the muon and electron g − 2 anomalies and dark matter

Abstract

We propose simple models with a flavor-dependent global U(1)ℓ and a discrete ℤ2 symmetries to explain the anomalies in the measured anomalous magnetic dipole moments of muon and electron, (g − 2)μ,e, while simultaneously accommodating a dark matter candidate. These new symmetries are introduced not only to avoid the dangerous lepton flavor-violating decays of charged leptons, but also to ensure the stability of the dark matter. Our models can realize the opposite-sign contributions to the muon and electron g − 2 via one-loop diagrams involving new vector-like leptons. Under the vacuum stability and perturbative unitarity bounds as well as the constraints from the dark matter direct searches and related LHC data, we find suitable parameter space to simultaneously explain (g − 2)μ,e and the relic density. In this parameter space, the coupling of the Higgs boson with muons can be enhanced by up to ∼ 38% from its Standard Model value, which can be tested in future collider experiments.

Power-aligned 2HDM: a correlative perspective on (g − 2)e,μ

“…For a sample of other recent suggestions made for the simultaneous explanation of the ∆a e,µ anomalies, we refer the readers to refs. [62][63][64][65][66][67][68][69][70][71][72][73][74][75][76][77][78].…”

Electron and muon $(g-2)$ in the 2HDM

“…In the literature, various mechanisms have been proposed to address these two anomalies simultaneously, e.g., by introducing lepto-quarks [6,7], in models with gauge-extension [8], by introducing new scalar states and fermionic states [9][10][11][12], etc. Here we discuss a minimal setup in which without extending the gauge sector of the SM or without introducing any exotic fermions or lepto-quarks, one could resolve these two anomalies simultaneously.…”

Leptonic g − 2 anomaly in an extended Higgs sector with vector-like leptons

“…It is important to note that anomalous MDM of the muon is opposite in sign to that of an electron and is much larger in magnitude that can be accounted for, by the electron mass scaling m 2 e /m 2 µ . Various attempts for simultaneous explanation of the leptonic anomalous magnetic moment anomalies have been made in the past several years [12][13][14][15][16][17][18][19][20][21][22][23][24][25][26]. Models with axionlike particles (ALP) [16], lepto-quarks [27,[30][31][32], vector-like leptons (VLL) [33][34][35][36][37][38][39] and super-symmetric models [28,29,[40][41][42] have been employed with varying success to explain the anomaly.…”