Search

We consider a smooth hybrid inflation scenario based on a supersymmetric SU(2)L X SU(2)R X U(1)B-L model. The Higgs triplets involved in the model play a key role in inflation as well as in explaining the observed baryon asymmetry of the Universe. We show that the baryon asymmetry can originate via nonthermal triplet leptogenesis from the decay of SU(2)L triplets, whose tiny vacuum expectation values also provide masses for the light neutrinos. [ABSTRACT FROM AUTHOR]

We discuss an extended standard model electroweak sector which contains a stable scalar dark matter particle, the D boson. To search for the D boson at the LHC we exploit the flavor-changing neutral current top quark decay, t→cDD, mediated by the lightest standard model-like Higgs h0 in a two Higgs doublet model framework. The branching ratio for t→cDD in this case can be as high as 10-3, after taking into account constraints arising from the D boson relic abundance. With an integrated luminosity of 10(100) fb-1, the 14 TeV LHC can explore values of this branching ratio that are one (two) order of magnitude smaller in tt¯ production with tt¯ →cb¯ ℓ-(c¯bℓ+)+ET. For a D boson mass ≲60 GeV, mh0≲2MZ, 10 fb-1 luminosity and a branching ratio BR(t→cDD)~10-4, the estimated number of signal events at the 14 TeV LHC is of order 80. [ABSTRACT FROM AUTHOR]

The discovery of the Higgs boson at the Large Hadron Collider (LHC) has a great impact on the minimal supersymmetric extension of the Standard Model (MSSM). In the context of the constrained MSSM (CMSSM) and its extension with nonuniversal masses for the MSSM Higgs doublets, sparticles with masses > 1 TeV are necessary to reproduce the observed Higgs boson mass of 125-126 GeV. On the other hand, there appears to be a significant amount of discrepancy between the measured muon g - 2 and the Standard Model prediction. A successful explanation of this discrepancy in the MSSM requires new contributions involving relatively light sparticles with masses < 1 TeV. In this paper, we attempt to accommodate the two conflicting requirements in a SU(5) inspired extension of the CMSSM. We assign nonuniversal but flavor blind soft supersymmetry breaking masses to the scalar components in 5 and 10 matter supermultiplets. The two MSSM Higgs doublets in the 5, 5 representations of SU(5) are also assigned unequal soft mass² at MGUT. We identify parameter regions which can simultaneously accommodate the observed Higgs boson mass and the muon g - 2 data, and which are compatible with other phenomenological constraints such as neutralino dark matter relic abundance and rare B-meson decays. Some regions of the allowed parameter space will be explored at the upgraded LHC and by dark matter direct detection experiments. [ABSTRACT FROM AUTHOR]

We consider two classes of supersymmetric flipped SU(5) models with gravity mediated supersymmetry breaking such that the thermal neutralino relic abundance provides the observed dark matter density in the universe. We estimate the muon flux induced by neutrinos that arise from neutralino annihilations in the Sun and discuss prospects for detecting this flux in the IceCube/Deep Core experiment. We also provide comparisons with the corresponding fluxes in the constrained minimal supersymmetric and nonuniversal Higgs models. Regions in the parameter space that can be explored by the IceCube/DeepCore experiment are identified. [ABSTRACT FROM AUTHOR]

If the lightest dark matter neutralino has a sufficiently large Higgsino component, its spin-independent and spin-dependent cross sections on nucleons can be sizable enough to be detected soon in direct and indirect surveys. We outline in this paper some characteristic features expected of mixed bino-Higgsino dark matter. If the observed relic density is saturated by the bino-Higgsino dark matter, it fixes the amount of allowable bino-Higgsino mixing and provides predictions for other observables which can be tested at the Large Hadron Collider (LHC). We study the correlation between the cross sections and the branching ratio of Bs→μ+μ-. For a mixed bino-Higgsino dark matter, the mass differences of the neutralinos can be less than MZ. This will cause an excess of lepton pairs, above the standard model predictions, from the decays of the two heavier neutralinos. We discuss implications of the dilepton invariant mass distribution, and outline a way to extract the neutralino parameters for testing gaugino mass unification and deducing the relic density from an interplay of astrophysical detection and LHC measurements. [ABSTRACT FROM AUTHOR]