Direct Constraints on Minimal Supersymmetry from Fermi-LAT Observations of the Dwarf Galaxy Segue 1

TL;DR

This study uses Fermi-LAT gamma-ray data from the dwarf galaxy Segue 1 to constrain the parameter space of the Constrained Minimal Supersymmetric Standard Model, focusing on neutralino dark matter.

Contribution

It provides the first detailed analysis combining gamma-ray observations with comprehensive supersymmetric model constraints, including spectral, spatial, and background modeling.

Findings

Low neutralino mass and high annihilation cross-section models are marginally disfavored.

Most disfavored models are already excluded by other experimental or relic density constraints.

Extrapolation suggests increased data may further constrain supersymmetric dark matter models.

Abstract

The dwarf galaxy Segue 1 is one of the most promising targets for the indirect detection of dark matter. Here we examine what constraints 9 months of Fermi-LAT gamma-ray observations of Segue 1 place upon the Constrained Minimal Supersymmetric Standard Model (CMSSM), with the lightest neutralino as the dark matter particle. We use nested sampling to explore the CMSSM parameter space, simultaneously fitting other relevant constraints from accelerator bounds, the relic density, electroweak precision observables, the anomalous magnetic moment of the muon and B-physics. We include spectral and spatial fits to the Fermi observations, a full treatment of the instrumental response and its related uncertainty, and detailed background models. We also perform an extrapolation to 5 years of observations, assuming no signal is observed from Segue 1 in that time. Results marginally disfavour models with low neutralino masses and high annihilation cross-sections. Virtually all of these models are however already disfavoured by existing experimental or relic density constraints.