The Likely Cause of the EGRET GeV Anomaly and its Implications

Understand

Analysis of data from the EGRET gamma-ray detector on the Compton Gamma Ray Observatory indicated an anomaly in the form of an excess diffuse galactic flux at GeV energies over that which was theoretically predicted.

• Various explanations for this anomaly have been put forth, including the invocation of supersymmetric dark matter annihilation.
• We reexamine these explanations here, including a new discussion of the possible systematic errors in the sensitivity determination of the EGRET detector.
• We conclude that the most likely explanation of the EGRET ``GeV anomaly'' was an error in the estimation of the of the EGRET sensitivity at energies above ~1 GeV.