1. Testing the Sensitivity of the Galactic Center Excess to the Point Source Mask
- Author
-
Yi-Ming Zhong, Patrick J. Fox, Samuel D. McDermott, and Ilias Cholis
- Subjects
Physics ,Point source ,Astrophysics::High Energy Astrophysical Phenomena ,Galactic Center ,Gamma ray ,General Physics and Astronomy ,Astrophysics::Cosmology and Extragalactic Astrophysics ,Astrophysics ,01 natural sciences ,Galaxy ,law.invention ,Telescope ,law ,0103 physical sciences ,Point (geometry) ,010306 general physics ,Astrophysics::Galaxy Astrophysics ,Luminosity function ,Fermi Gamma-ray Space Telescope - Abstract
The Fermi Large Area Telescope (Fermi-LAT) Collaboration has an updated point source catalog, referred to as 4FGL. We perform the first template fit using a mask based on this new catalog and find that the excess in gamma rays detected at the Galactic Center in Fermi-LAT data persists. On the other hand, we find that a search for point sources is highly sensitive to the use of the 4FGL catalog: no sizable excess of bright pixels is apparent in the inner Galaxy when we mask out 4FGL point sources. Combining these observations restricts the ability of point sources to contribute to the Galactic Center excess. After identifying which bright sources have no known counterpart, we place strong constraints on any point source luminosity function capable of explaining the smooth emission identified in the template fit.
- Published
- 2020