Searching for light from a dark matter clump

TL;DR

This paper investigates the possibility of detecting gamma-ray signals from a dark matter clump suggested by DAMPE data, but finds no such excess in Fermi-LAT observations, challenging the dark matter interpretation.

Contribution

It provides a critical analysis comparing DAMPE's dark matter interpretation with Fermi-LAT gamma-ray data, ruling out the expected gamma-ray excess.

Findings

No gamma-ray excess observed in Fermi-LAT data.

Challenges the dark matter annihilation explanation for DAMPE's electron spectrum.

Highlights the need for alternative explanations or further data.

Abstract

The DAMPE experiment has recently reported an electron spectrum that can be explained by dark matter annihilation into charged lepton pairs in a nearby dark matter clump. The accompanying bremsstrahlung may yield a gamma-ray excess with a known spectral shape that extends over an angular scale of $O(10^\circ)$. We show that such an excess is not present in Fermi-LAT data.