Content area
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 19 TeV.
Details
1 Nagoya University, Institute for Advanced Research, Nagoya, Japan (GRID:grid.27476.30) (ISNI:0000 0001 0943 978X); Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya, Japan (GRID:grid.27476.30) (ISNI:0000 0001 0943 978X)
2 Nagoya University, Department of Physics, Nagoya, Japan (GRID:grid.27476.30) (ISNI:0000 0001 0943 978X)
3 Nagoya University, Kobayashi-Maskawa Institute for the Origin of Particles and the Universe, Nagoya, Japan (GRID:grid.27476.30) (ISNI:0000 0001 0943 978X); Nagoya University, Department of Physics, Nagoya, Japan (GRID:grid.27476.30) (ISNI:0000 0001 0943 978X); University of Tokyo, Kavli IPMU (WPI), UTIAS, Kashiwa, Japan (GRID:grid.26999.3d) (ISNI:0000 0001 2151 536X)