| We first present a new model of composite Higgs based on a gauged SU(N)group with 4 Dirac fermions in the fundamental representation.At low energy,the model has a global symmetry S U(4)L × S U(4)R broken to the diagonal S U(4)D,containing 2 Higgs doublets in the coset.We study in detail the issue of the vacuum alignment.In particular,we prove that,without loss of generality,the vacuum can always be aligned with one doublet.This model has a good symmetry.Under certain conditions on the top preYukawas,the second doublet and the additional triplets is protected by this symmetry and can thus play the role of Dark Matter.So it is the first fundamental composite higgs model that contain a dark matter candidate naturally and it has the same available space of parameters as the minimal fundamental composite higgs model S U(4)/S p(4).We then study its phenomenology to constrain its available parameter space under this symmetry.we generally analyze the physical property of all the additional scalars and find the singlet scalar has similar physics to the singlet in the minimal composite higgs model.The lightest mass eigenstate among the second higgs doublet and the triplets can play the role of dark matter if this symmetry is conserved.We fully analyze the phenomenology of this dark matter candidate in LHC.We calculate its relic density to get the upper bound of its mass by comparing with dark matter relic density in cosmology.We find its mass need to be several TeV for producing enough relic density.We also give its mass a lower bound based on current dark matter direct and indirect detection. |
PDF Full Text Request