Solving the muon g-2 anomaly in CMSSM extension with non-universal gaugino masses

Abstract

We propose to generate non-universal gaugino masses in SU(5) Grand Unified Theory (GUT) with the generalized Planck-scale mediation SUSY breaking mechanism, in which the non-universality arises from proper wavefunction normalization with lowest component VEVs of various high dimensional representations of the Higgs fields of SU(5) and an unique F-term VEV by the singlet. Different predictions on gaugino mass ratios with respect to widely studied scenarios are given. The gluino-SUGRA-like scenario, where gluinos are much heavier than winos, bino and universal scalar masses, can be easily realized with appropriate combinations of such high-representation Higgs fields. With six GUT-scale free parameters in our scenario, we can solve elegantly the tension between mSUGRA and the present experimental results, including the muon g-2, the dark matter (DM) relic density and the direct sparticle search bounds from the LHC. Taking into account the current constraints in our numerical scan, we have the following observations: (i) The large-tan β (≳35) samples with a moderate M3 (∼5 TeV), a small |A0/M3| (≲0.4) and a small mA (≲4 TeV) are favoured to generate a 125 GeV SM-like Higgs and predict a large muon g-2, while the stop mass and μ parameter, mainly determined by |M3| (≫ M0, |M1|, |M2|), can be about 6 TeV; (ii) The moderate-tan β (35 ∼ 40) samples with a negative M3 can have a light smuon (250 ∼ 450 GeV) but a heavy stau (≳1 TeV), which predict a large muon g-2 but a small Br(Bs → μ+μ−); (iii) To obtain the right DM relic density, the annihilation mechanisms should be stau exchange, stau coannihilation, chargino coannihilation, slepton annihilation and the combination of two or three of them; (iv) To obtain the right DM relic density, the spin-independent DM-nucleon cross section is typically much smaller than the present limits of XENON1T 2018 and also an order of magnitude lower than the future detection sensitivity of LZ and XENONnT experiments.