Gamma rays and positrons from a decaying hidden gauge boson

TL;DR

This paper explores a hidden gauge boson as a dark matter candidate that decays into standard model particles, producing gamma rays and positrons with distinctive spectral features that could explain existing astrophysical anomalies.

Contribution

It proposes a decaying hidden gauge boson model for dark matter that accounts for gamma ray and positron excesses with unique spectral signatures.

Findings

Gamma rays and positrons from decay match EGRET and HEAT anomalies.

Spectral features include no gamma-ray line and a sharp positron peak.

Predictions are testable by GLAST and PAMELA satellites.

Abstract

We study a scenario that a hidden gauge boson constitutes the dominant component of dark matter and decays into the standard model particles through a gauge kinetic mixing. Interestingly, gamma rays and positrons produced from the decay of hidden gauge boson can explain both the EGRET excess of diffuse gamma rays and the HEAT anomaly in the positron fraction. The spectra of the gamma rays and the positrons have distinctive features; the absence of line emission of the gamma ray and a sharp peak in the positron fraction. Such features may be observed by the GLAST and PAMELA satellites.