Positron fraction from dark matter annihilation in the CMSSM

Abstract

We investigate, if the cosmic ray positron fraction, as reported by the HEAT and AMS collaborations, is compatible with the annihilation of neutralinos in the supergravity inspired Constrained Minimal Supersymmetric Model (CMSSM), thus complementing previous investigations, which did not consider constraints from unification, electroweak symmetry breaking and the present Higgs limits at LEP. We consider in a global analysis the complete SUSY parameter space and find that in the acceptable regions that neutralino annihilate dominantly into $\text{b}\text{b}$ quark pairs. The positrons from $\text{b}\text{b}$ improve the fit to the experimental positron fraction data considerably compared to a fit with background only.