Hunting the lightest lightest neutralinos

Abstract

The lightest neutralino in the minimal supersymmetric extension of the Standard Model can be, in principle, massless. If super-light neutralinos are the dark matter, structure formation constrains their mass to be above a few keV. We show that relaxing the assumption of radiation domination and entropy conservation prior to Big Bang Nucleosynthesis, the relic abundance of very light neutralinos can be consistent with the inferred cold dark matter density. We study how we can hunt for light neutralino dark matter, with a mass at or below a GeV, focusing on both direct and indirect searches. We argue that the two most promising channels are spin-dependent direct detection and the search for monochromatic gamma rays from the prompt pair-annihilation of neutralinos into photons with GLAST. Our study indicates that the lightest lightest neutralinos can be detected as long as their mass is above a few tenth of a GeV, a mass range where a future linear collider could provide important information on the details of the particle dark matter model.

14 pages, 5 figures, accepted for publication in Phys.Rev.D

References in corpus (6)

• How cold is cold dark matter? Small scales constraints from the flux power spectrum of the high-redshift Lyman-alpha forest
• Measuring superparticle masses at hadron collider using the transverse mass kink
• Neutralino Dark Matter Detection in Split Supersymmetry Scenarios
• Zooming in on light relic neutralinos by direct detection and measurements of galactic antimatter
• Challenges for MSSM Higgs searches at Hadron Colliders
• Light neutralinos at LHC in cosmologically-inspired scenarios: new benchmarks in the search for supersymmetry

Cited by in corpus (2)

• Conservative Constraints on Dark Matter Annihilation into Gamma Rays
• Direct/indirect detection signatures of nonthermally produced dark matter