26th International Conference on Supersymmetry and Unification of Fundamental Interactions (SUSY2018)

23-27 July 2018
Barcelona
Europe/Zurich timezone

Same-sign trilepton signal for a stop in presence of sneutrino LSP

25 Jul 2018, 14:50
20m
Room A

Speaker

Dr Subhadeep Mondal (University of Helsinki)

Description

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

Primary author

Dr Subhadeep Mondal (University of Helsinki)

Co-authors

Prof. DILIP KUMAR GHOSH (INDIAN ASSOCIATION FOR THE CULTIVATION OF SCIENCE) Dr Manimala Mitra (Institute of Physics (IOP)) Prof. Katri Huitu (University of Helsinki)