Is The Gamma-Ray Source 3FGL J2212.5+0703 A Dark Matter Subhalo?

In a previous paper, we pointed out that the gamma-ray source 3FGL J2212.5+0703 shows evidence of being spatially extended. If a gamma-ray source without detectable emission at other wavelengths were unambiguously determined to be spatially extended, it could not be explained by known astrophysics,...

Ausführliche Beschreibung

Gespeichert in:
Bibliographische Detailangaben
Veröffentlicht in:arXiv.org 2016-02
Hauptverfasser: Bertoni, Bridget, Hooper, Dan, Linden, Tim
Format: Artikel
Sprache:eng
Schlagworte:
Online-Zugang:Volltext
Tags: Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
Beschreibung
Zusammenfassung:In a previous paper, we pointed out that the gamma-ray source 3FGL J2212.5+0703 shows evidence of being spatially extended. If a gamma-ray source without detectable emission at other wavelengths were unambiguously determined to be spatially extended, it could not be explained by known astrophysics, and would constitute a smoking gun for dark matter particles annihilating in a nearby subhalo. With this prospect in mind, we scrutinize the gamma-ray emission from this source, finding that it prefers a spatially extended profile over that of a single point-like source with 5.1 sigma statistical significance. We also use a large sample of active galactic nuclei and other known gamma-rays sources as a control group, confirming, as expected, that statistically significant extension is rare among such objects. We argue that the most likely (non-dark matter) explanation for this apparent extension is a pair of bright gamma-ray sources that serendipitously lie very close to each other, and estimate that there is a chance probability of ~2% that such a pair would exist somewhere on the sky. In the case of 3FGL J2212.5+0703, a model with a second gamma-ray point source at the location of a known BZCAT/CRATES radio source yields fits that are comparable in quality to those obtained for a single extended source. If 3FGL J2212.5+0703 is a dark matter subhalo, it would imply that dark matter particles have a mass of ~18-33 GeV and an annihilation cross section on the order of sigma v ~ 10^-26 cm^3/s (for the representative case of annihilations to bb), similar to the values required to generate the Galactic Center gamma-ray excess.
ISSN:2331-8422
DOI:10.48550/arxiv.1602.07303