Searching for SUSY and decaying gravitino DM at the LHC and Fermi-LAT with the $\mu\nu$SSM

TL;DR

This paper explores the $$SSM model's unique signatures at the LHC and Fermi-LAT, focusing on supersymmetry detection and gravitino dark matter constraints through collider and gamma-ray observations.

Contribution

It introduces novel signatures of supersymmetry in the $$SSM and analyzes gamma-ray constraints on gravitino dark matter from Fermi-LAT data.

Findings

Fermi-LAT data constrains gravitino mass to 5-20 GeV.

Lower bounds on gravitino lifetime are around 10^{25-28} seconds.

New supersymmetry signatures involve multi-leptons, jets, photons, and displaced vertices.

Abstract

The `$\mu$ from $\nu$' supersymmetric standard model ($\mu\nu$SSM) solves the $\mu$ problem of supersymmetric models and reproduces neutrino data, simply using couplings with the three families of right-handed neutrinos $\nu$'s. Novel signatures of supersymmetry at the LHC are expected through these new states, and couplings breaking $R$ parity. All supersymmetric particles are potential candidates for the lightest one, which is not stable leading to prompt or displaced vertices and producing final states with multi-leptons/taus/jets/photons and missing energy. Besides, a decaying gravitino turns out to be an interesting candidate for dark matter. It can be searched through gamma-ray observations, such as those of the Fermi Large Area Telescope. The latter, depending on the region of the parameter space of the model, already imposes an upper bound on the gravitino mass of the order of $5-20$ GeV and a lower bound on the lifetime of about $10^{25-28}$ s.