A model of electroweakly interacting non-abelian vector dark matter

Abstract

We propose an electroweakly interacting spin-1 dark matter (DM) model. The electroweak gauge symmetry, SU(2)L×U(1)Y , is extended into SU(2)0×SU(2)1×SU(2)2×U(1)Y . A discrete symmetry exchanging SU(2)0 and SU(2)2 is imposed. This discrete symmetry stabilizes the DM candidate. The spin-1 DM particle (V0) and its SU(2)L partners (V±) interact with the Standard Model (SM) electroweak gauge bosons without any suppression factors. Consequently, pairs of DM particles efficiently annihilate into the SM particles in the early universe, and the measured value of the DM energy density is easily realized by the thermal freeze-out mechanism. The model also predicts a heavy vector triplet (W′± and Z′) in the visible sector. They contribute to the DM annihilation processes. The mass ratio of Z′ and V0 determines values of various couplings, and constraints on W′ and Z′ restrict regions of the parameter space that are viable for DM physics. We investigate the constraints from perturbative unitarity of scalar and gauge couplings, the Higgs signal strength, W′ search at the LHC, and DM direct detection experiments. It is found that the relic abundance of V0 explains the right amount of the DM energy density for 3 TeV $$ \underset{\sim }{<}{m}_Vo\underset{\sim }{<} $$ < ∼ m V o < ∼ 19 TeV.

Gamma-ray line from electroweakly interacting non-abelian spin-1 dark matter

“…To reveal the general features of spin-1 DM, we construct the renormalizable fourdimensional model of electroweakly interacting non-abelian spin-1 DM [15]. This model is the minimal setup that realizes the fundamental features of the five-dimensional model of the spin-1 DM such as the Z 2 -parity and the degenerated mass spectrum.…”

“…We briefly introduce a model of electroweakly interacting non-abelian vector DM [15]. We extend the electroweak gauge symmetry in the SM into SU (2)…”

“…In the following discussion, we focus on φ h 0.1 to evade the direct detection constraints [15]. 2 The U(1)em symmetry generator is expressed as Q = T 3 0 + T 3 1 + T 3 2 + Y where T 3 n denote the third generators of SU(2)n (n = 0, 1, 2).…”

Vector dark matter from split SU(2) gauge bosons

“…gauge groups, such as SU(2) [21,[30][31][32][33][34][35][36][37][38][39][40][41][42][43], SU(2)⊗U(1) [44][45][46][47], SU(2)⊗SU(2) [48], SU(3) [21,35,[49][50][51][52], and general SU(N ) [21,35]. Typically, some discrete or global continuous symmetries remain after gauge symmetry breaking, stabilizing the vector DM particle.…”

Feebly coupled vector boson dark matter in effective theory

“…Vector boson DM (VDM) candidate can only appear in models with extended gauge group, the simplest being an Abelian U(1). Many possibilities of an Abelian VDM have been studied [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37], while non-Abelian extensions to adopt VDM are fewer [38][39][40][41][42][43][44][45][46]. The VDM can become massive after spontaneous symmetry breaking of the additional gauge group and often requires additional stabilizing symmetry G DM [20,38].…”