Hints of a Charge Asymmetry in the Electron and Positron Cosmic-Ray Excesses

TL;DR

This paper analyzes combined AMS-02 and Fermi-LAT data to reveal a potential charge asymmetry in cosmic-ray electron and positron excesses, suggesting asymmetric production mechanisms may be involved.

Contribution

It introduces the first evidence of charge asymmetry in cosmic-ray excesses and classifies models based on their predictions for this asymmetry and its energy dependence.

Findings

Charge asymmetry slightly favors electrons over positrons.

Astrophysical and dark matter models differ in their predictions for asymmetry.

Future data could confirm asymmetric production mechanisms.

Abstract

By combining the recent data from AMS-02 with those from Fermi-LAT, we show the emergence of a charge asymmetry in the electron and positron cosmic-ray excesses, slightly favoring the electron component. Astrophysical and dark matter inspired models introduced to explain the observed excesses can be classified according to their prediction for the charge asymmetry and its energy dependence. Future data confirming the presence of a charge asymmetry, would imply that an asymmetric production mechanism is at play.