Abstract
We explore a minimal supersymmetric standard model scenario extended by one pair of gauge singlets per generation. In the model, light neutrino masses and their mixings are generated via the inverse seesaw mechanism. In such a scenario, a right-handed sneutrino can be the lightest supersymmetric particle and a cold dark matter (DM) candidate. If the Casas-Ibarra parametrization is imposed on the Dirac neutrino Yukawa coupling matrix () to fit the neutrino oscillation data, the resulting is highly constrained from the lepton-flavor-violating decay constraints. The smallness of requires the sneutrino DM to coannihilate with other sparticle(s) in order to satisfy the DM relic density constraint. We study sneutrino coannihilation with winos and observe that this sneutrino-wino compressed parameter space gives rise to a novel same-sign trilepton signal for the top squark, which is more effective than the conventional top squark search channels in the present framework. We show that the choice of neutrino mass hierarchy strongly affects the signal event rate, making it easier to probe the scenario with the inverted mass hierarchy.
- Received 29 November 2018
DOI:https://doi.org/10.1103/PhysRevD.99.075014
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article’s title, journal citation, and DOI. Funded by SCOAP3.
Published by the American Physical Society