Galactic center gamma-ray excess and the Fermi bubbles

TL;DR

This paper examines how modeling the Fermi bubbles at low latitudes affects the gamma-ray excess observed at the Galactic center, which is crucial for understanding potential dark matter signals.

Contribution

It introduces a new template for the Fermi bubbles at low latitudes and analyzes its impact on the gamma-ray excess spectrum at the Galactic center.

Findings

Fermi bubbles near the GC significantly influence the gamma-ray spectrum above 10 GeV.

Modeling the bubbles alters the interpretation of the gamma-ray excess.

The presence of bubbles may affect dark matter signal analysis.

Abstract

Galactic center (GC) is expected to be the brightest source of possible dark matter (DM) annihilation signal. Excess gamma-ray emission has been detected by several groups. Both DM and more conventional astrophysical explanations of the excess have been proposed. In this report, we discuss possible effects of modeling the Fermi bubbles at low latitudes on the GC excess. We consider a template of the Fermi bubbles at low latitudes derived by assuming that the spectrum between 1 GeV and 10 GeV at low latitudes is the same as at high latitudes. We argue that the presence of the Fermi bubbles near the GC may have a significant influence on the spectrum of the GC excess, especially at energies above 10 GeV.