Multi-component dark matter with magnetic moments for Fermi-LAT gamma-ray line

Abstract

We propose a model of multi-component dark matter with magnetic moments to explain the 130 GeV gamma-ray line hinted by the Fermi-LAT data. Specifically, we consider a U (1) X dark sector which contains two vector-like fermions besides the related gauge and Higgs fields. A very heavy messenger scalar is further introduced to construct the Yukawa couplings of the dark fermions to the heavy [SU (2)]-singlet leptons in the SU (3) c ×SU (2) L ×SU (2) R ×U (1) B−L left-right symmetric models for universal seesaw. A heavier dark fermion with a very long lifetime can mostly decay into a lighter dark fermion and a photon at one-loop level. The dark fermions can serve as the dark matter particles benefited from their annihilations into the dark gauge and Higgs fields. In the presence of a U (1) kinetic mixing, the dark matter fermions can be verified by the ongoing and forthcoming dark matter direct detection experiments. PACS numbers: 95.35.+d, 12.60.Cn, 12.60.Fr

Two dark matter candidates: the case of inert doublet and singlet scalars

“…Processes such as semi-annihilation [32][33][34] where two DM annihilate into a DM and a SM particle, or processes called dark annihilation or DM conversion where a pair of DM particles annihilate into another pair of DM particles [35] as well as the decay of one DM into another component can all play an important role in the early Universe. Examples of simple extensions of the SM that have these features include models with two scalars [30,[36][37][38][39][40][41], two fermions [29,[42][43][44][45][46] or two vectors [47,48] as DM candidates, models with a combination of scalar, fermion and vector DM [49][50][51][52][53][54][55][56] as well as other multi-component models [57][58][59][60]. In such models the DM components can be stabilized by a discrete symmetry such as Z 2 × Z 2 [61][62][63][64] or Z N with N > 4 [31,[65][66][67][68][69] The modifications to DM formation not only impacts the value of the relic density but also of various observables such as DM direct detection through DM scattering in a large underground detector, and/or specific indirect det...…”

Type III seesaw for neutrino masses in U(1)B−L model with multi-component dark matter

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Neutron stars with spin polarized self-interacting dark matter

“…In that study, the dipole moments for the WIMP have been applied with the conventional magnetism and also dark magnetism and both magnetic-magnetic and magnetic-electric scattering. Moreover, a model of multi-component DM with magnetic moments has been presented to describe the 130 GeV gamma-ray line hinted by the Fermi-LAT data [40]. Another aspects of the magnetic properties of DM particles has been suggested in Ref.…”