A Supersymmetric B-L Dark Matter Model and the Observed Anomalies in the Cosmic Rays

TL;DR

This paper introduces a supersymmetric B-L extension model of dark matter that explains cosmic ray anomalies observed by PAMELA and ATIC through specific annihilation channels and Sommerfeld enhancement effects.

Contribution

It presents a novel supersymmetric B-L model with a TeV-scale Higgs that accounts for cosmic ray anomalies and predicts observable signals for future experiments.

Findings

Model fits PAMELA and ATIC data with 1-2 TeV dark matter mass.

Light Higgs mediates dark matter annihilation mainly into taus or muons.

Sommerfeld enhancement increases annihilation cross section significantly.

Abstract

We propose a simple model of supersymmetric dark matter that can explain recent results from PAMELA and ATIC experiments. It is based on a U(1)_B-L extension of the minimal supersymmetric standard model. The dark matter particle is a linear combination of the U(1)_B-L gaugino and Higgsino partners of Higgs fields that break the B-L around one TeV. The dominant mode of dark matter annihilation is to the lightest of the new Higgs fields, which has a mass in the GeV range, and its subsequent decay mainly produces taus or muons by the virtue of B-L charges. This light Higgs also results in Sommerfeld enhancement of the dark matter annihilation cross section, which can be >~ 10^3. For a dark matter mass in the 1-2 TeV range, the model provides a good fit to the PAMELA data and a reasonable fit to the ATIC data. We also briefly discuss the prospects of this model for direct detection experiments and the LHC.