Positrons in Cosmic Rays from Dark Matter Annihilations for Uplifted Higgs Regions in MSSM

TL;DR

This paper identifies specific MSSM parameter space regions, like the uplifted Higgs region, where neutralino dark matter annihilations can explain positron excesses observed by PAMELA, while remaining consistent with other astrophysical data.

Contribution

It demonstrates that MSSM can naturally account for positron excesses via resonant annihilation into leptons without extra particles.

Findings

MSSM regions can produce the correct relic density.

Annihilation predominantly into leptons explains positron excess.

Compatible with antiproton and gamma-ray constraints.

Abstract

We point out that there are regions in the MSSM parameter space which successfully provide a dark matter (DM) annihilation explanation for observed positron excess (e.g. PAMELA), while still remaining in agreement with all other data sets. Such regions (e.g. the uplifted Higgs region) can realize an enhanced neutralino DM annihilation dominantly into leptons via a Breit-Wigner resonance through the CP-odd Higgs channel. Such regions can give the proper thermal relic DM abundance, and the DM annihilation products are compatible with current antiproton and gamma ray observations. This scenario can succeed without introducing any additional degrees of freedom beyond those already in the MSSM.