PoS - Proceedings of Science
Volume 395 - 37th International Cosmic Ray Conference (ICRC2021) - GAD - Gamma Ray Direct
The Mysterious Gamma-Ray Excess of Andromeda: Comparing Millisecond Pulsars to Dark Matter
F. Zimmer
Full text: pdf
Pre-published on: July 04, 2021
Published on: March 18, 2022
The discovery of an excess in gamma rays coming from the center of our Milky Way galaxy in 2009 has opened up an exciting field in the search for dark matter. More recently in 2017, another such an excess has been confirmed to be present in the Andromeda galaxy. In this work we analyze 10 years of Fermi-LAT data in the attempt to rigorously characterize the significance of this excess when accounting for uncertainties coming from difficulties in modeling the gamma-ray background. For this purpose we constructed specific background models for the Andromeda sky region, employing modern inpainting techniques based on algorithms involving neural networks. We furthermore developed models for testing the hypothesis that this signal could be caused by a population of millisecond pulsars (MSPs), which are as of yet unresolved by the Fermi space telescope. Our findings indicate, that the emission of annihilating dark matter is unwarranted when accounting for the emission of the beforementioned pulsars or contributions from interstellar gas and dust. The results of this work build up on previous attempts on this matter, but we use a more sophisticated and robust statistical framework in combination with templates specifically constructed for this purpose alone.
DOI: https://doi.org/10.22323/1.395.0673
How to cite

Metadata are provided both in "article" format (very similar to INSPIRE) as this helps creating very compact bibliographies which can be beneficial to authors and readers, and in "proceeding" format which is more detailed and complete.

Open Access
Creative Commons LicenseCopyright owned by the author(s) under the term of the Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.