Phenomenology of Light Sneutrino Dark Matter in cMSSM/mSUGRA with Inverse Seesaw

TL;DR

This paper explores a light sneutrino dark matter candidate within a cMSSM framework extended by an inverse seesaw mechanism, demonstrating it can satisfy experimental constraints and produce distinctive collider signatures.

Contribution

It introduces a novel light sneutrino dark matter scenario in cMSSM with inverse seesaw, highlighting unique collider signals and implications for Higgs decay.

Findings

Light sneutrino DM below 100 GeV is viable under current constraints.

Enhanced same-sign dilepton signals with large missing energy are predicted.

Implications for Higgs invisible decay width are discussed.

Abstract

We study the possibility of a light Dark Matter (DM) within a constrained Minimal Supersymmetric Standard Model (cMSSM) framework augmented by a SM singlet-pair sector to account for the non-zero neutrino masses by inverse seesaw mechanism. Working within a 'hybrid' scenario with the MSSM sector fixed at high scale and the singlet neutrino sector at low scale, we find that, contrary to the case of the usual cMSSM where the neutralino DM cannot be very light, we can have a light sneutrino DM with mass below 100 GeV satisfying all the current experimental constraints from cosmology, collider as well as low-energy experiments. We also note that the supersymmetric inverse seesaw mechanism with sneutrino as the lightest supersymmetric partner can have enhanced same-sign dilepton final states with large missing transverse energy (mET) coming from the gluino- and squark-pair as well as the squark-gluino associated productions and their cascade decay through charginos. We present a collider study for the same-sign dilepton+jets+mET signal in this scenario and propose some distinctions with the usual cMSSM. We also comment on the implications of such a light DM scenario on the invisible decay width of an 125 GeV Higgs boson.