Cosmic Ray Proton Background Could Explain ATIC Electron Excess

TL;DR

The paper suggests that the observed electron excess in ATIC data may be due to misidentified proton events, and removing this component resolves the excess, impacting interpretations of cosmic ray data.

Contribution

It introduces a simple method to account for proton contamination in ATIC electron measurements, explaining the excess without new physics.

Findings

Proton contamination can mimic electron signals in ATIC.

Subtracting proton contribution removes the electron excess.

The excess may not indicate new phenomena, but detector effects.

Abstract

We show that the excess in the Galactic electron flux recently published by Chang, et al. (Nature, 20 Nov. 2008) can have a simple methodical origin due to a contribution from misidentified proton induced electron-like events in the ATIC detector. A subtraction of the cosmic ray proton component from the published ATIC electron flux eliminates this excess in the range of 300 to 800 GeV.