Sneutrino Dark Matter in the BLSSM

TL;DR

This paper investigates the sneutrino as a dark matter candidate within the BLSSM, analyzing its relic density, potential detection via gamma-ray spectra, and collider signatures, highlighting the complementarity of different experimental approaches.

Contribution

It provides a comprehensive analysis of sneutrino dark matter in the BLSSM, combining relic density constraints, gamma-ray detection prospects, and collider signatures, which is a novel multi-faceted approach.

Findings

Sneutrino relic density matches Planck data in certain parameter regions.

High-energy gamma-ray spectra can reveal sneutrino annihilations into W+W-.

LHC multi-lepton signatures could potentially detect sneutrino dark matter.

Abstract

In the framework of the $(B-L)$ Supersymmetric Standard Model (BLSSM), we assess the ability of ground and space based experiments to establish the nature of its prevalent Dark Matter (DM) candidate, the sneutrino, which could either be CP-even or -odd. Firstly, by benchmarking this theory construct against the results obtained by the Planck spacecraft, we extract the portions of the BLSSM parameter space compliant with relic density data. Secondly, we show that, based on current sensitivities of the Fermi Large Area Telescope (FermiLAT) and their future projections, the study of high-energy $\gamma$-ray spectra will eventually enable us to extract evidence of this DM candidate through its annihilations into $W^+W^-$ pairs (in turn emitting photons), in the form of both an integrated flux and a differential energy spectrum which cannot be reconciled with the assumption of DM being fermionic (like, e.g., a neutralino), although it should not be possible to distinguish between the scalar and pseudoscalar hypotheses. Thirdly, we show that, while underground direct detection experiments will have little scope in testing sneutrino DM, the Large Hadron Collider (LHC) may be able to do so in a variety of multi-lepton signatures, with and without accompanying jets (plus missing transverse energy), following data collection during Run 2 and 3.