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Register a new userDark Matter and Solar Neutrinos in SUSY
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D. Tommasini
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In the Supersymmetric extension of the Standard Model with minimal particle content the three neutrinos can have non trivial masses and mixings, generated at 1 loop due to renormalizable lepton number violating interactions. We show that the resulting mass matrix can provide simultaneously a significant amount of the Dark Matter of the Universe and solve the solar neutrino problem, if the free parameters of the model are fixed to values which are consistent with all the present accelerator and cosmological constraints. The theory also predicts new effects in future experiments looking for neutrino oscillations.
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The coherent contribution of all neutrons in neutrino nucleus scattering due to the neutral current is examined considering the boron solar neutrinos. These neutrinos could potentially become a source of background in the future dark matter searches aiming at nucleon cross sections in the region well below the few events per ton per year.
Null results from dark matter (DM) direct detection experiments and the 125 GeV Higgs both pose serious challenges to minimal supersymmetry. In this paper, we propose a simple extension of the MSSM that economically solves both problems: a dark sector consisting of a singlet and a pair of $SU(2)$ doublets. Loops of the dark sector fields help lift the Higgs mass to 125 GeV consistent with naturalness, while the lightest fermion in the dark sector can be viable thermal relic DM, provided that it is mostly singlet. The DM relic abundance is controlled by s-wave annihilation to tops and Higgsinos, leading to a tight relation between the relic abundance and the spin-dependent direct detection cross section. As a result, the model will be fully probed by the next generation of direct detection experiments. Finally we discuss the discovery potential at LHC Run II.
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The searches for heavy Higgs bosons and supersymmetric (SUSY) particles at the LHC have left the minimal supersymmetric standard model (MSSM) with an unusual spectrum of SUSY particles, namely, all squarks are beyond a few TeV while the Higgs bosons other than the one observed at 125 GeV could be relatively light. In light of this, we study a scenario characterized by two scales: the SUSY breaking scale or the squark-mass scale $(M_S)$ and the heavy Higgs-boson mass scale $(M_A)$.We perform a survey of the MSSM parameter space with $M_S < 10^{10}$ GeV and $M_A < 10^4$ GeV such that the lightest Higgs boson mass is within the range of the observed Higgs boson as well as satisfying a number of constraints. The set of constraints include the invisible decay width of the $Z$ boson and that of the Higgs boson, the chargino-mass limit, dark matter relic abundance from Planck, the spin-independent cross section of direct detection by LUX, and gamma-ray flux from dwarf spheroidal galaxies and gamma-ray line constraints measured by Fermi LAT. Survived regions of parameter space feature the dark matter with correct relic abundance, which is achieved through either coannihilation with charginos, $A/H$ funnels, or both. We show that future measurements, e.g., XENON1T and LZ, of spin-independent cross sections can further squeeze the parameter space.
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