We have explored a minimal supersymmetric Standard Model scenario extended by one pair of gauge singlets per generation, where light neutrino masses and mixing are generated via inverse seesaw mechanism. In such a scenario, a right-handed sneutrino can be the lightest supersymmetric particle and a cold Dark Matter (DM) candidate. We have studied the constraints on such a scenario arising from non-observation lepton flavor violating (LFV) decays and DM data. We have observed that if the Dirac neutrino Yukawa coupling matrix is used to fit the neutrino oscillation data by Casas-Ibarra parametrisation, the resulting off-diagonal matrix is highly constrained from the LFV data. The resultant Yukawa parameter(s), also responsible for the sneutrino DM couplings, produces a very small direct detection cross-section lying orders of magnitude below the present XENON limit. However, the smallness of the Yukawa parameters also requires the sneutrino DM to co-annihilate with other sparticle(s) in order to satisfy DM relic density constraints. We have studied sneutrino co-annihilation with wino and observed that this sneutrino-wino compressed parameter space gives rise to a novel same-sign trilepton signal for the stop quark in this scenario.
|Parallel Session||Supersymmetry: Models, Phenomenology and Experimental Results|