PAMELA/Fermi-LAT electron cosmic ray spectrum at $\sim$100 GeV: implication for dark matter annihilation signal in accordance with the 130 GeV $\gamma$-ray line

TL;DR

This paper explores the possible connection between a tentative 130 GeV gamma-ray line signal and subtle features in cosmic ray electron spectra, suggesting a potential dark matter annihilation signature detectable by AMS-02.

Contribution

It proposes that tiny wiggle-like structures in cosmic ray electron spectra may indicate dark matter annihilation at 130 GeV, and discusses the prospects for detection by AMS-02.

Findings

Cosmic ray electron spectra show wiggle-like features near 100 GeV.

These features could be linked to dark matter annihilation at 130 GeV.

AMS-02 could potentially detect this weak dark matter signal.

Abstract

Recently, a tentative 130 GeV $\gamma$-ray line signal was identified by quite a few groups. If correct it would constitute a ``smoking gun'' for dark matter annihilations. Interestingly, the spectra of the cosmic ray electrons detected by PAMELA and Fermi-LAT both show tiny wiggle-like structure at $\sim 100$ GeV, which might indicate a weak signal of the annihilation of $\sim 130$ GeV dark matter particles into electrons/positrons with a velocity-weighted cross section $\langle\sigma v\rangle_{\rm \chi\chi\rightarrow e^{+}e^{-}} \sim 4\times10^{-26}~{\rm cm^{3}~s^{-1}}$. The prospect of identifying such a potential weak dark-matter-annihilation electron and/or positron component by AMS-02, a mission to measure the high energy cosmic ray spectra with unprecedented accuracy, is investigated.