If you’re a long-time astrobites reader with interests that extend to the fascinating and vibrant field of particle physics, you’ll love the work being published at our sister site particlebites. Like astrobites, particlebites authors are graduate students that cover the latest research in their field, particle physics, by posting concise and engaging summaries of newly published research and preprints. Below is an excerpt from a post by particlebites guest author Chris Karwin.
The center of the galaxy is brighter than astrophysicists expected. Could this be the result of the self-annihilation of dark matter? Chris Karwin, a graduate student from the University of California, Irvine presents the Fermi collaboration’s analysis.
Presenting: Fermi-LAT Observations of High-Energy Gamma-Ray Emission Toward the Galactic Center
Authors: The Fermi-LAT Collaboration (ParticleBites blogger is a co-author)
Reference: 1511.02938, Astrophys.J. 819 (2016) no.1, 44
Like other telescopes, the Fermi Gamma-Ray Space Telescope is a satellite that scans the sky collecting light. Unlike many telescopes, it searches for very high energy light: gamma-rays. The satellite’s main component is the Large Area Telescope (LAT). When this detector is hit with a high-energy gamma-ray, it measures the the energy and the direction in the sky from where it originated. The data provided by the LAT is an all-sky photon counts map:
In 2009, researchers noticed that there appeared to be an excess of gamma-rays coming from the galactic center. This excess is found by making a model of the known astrophysical gamma-ray sources and then comparing it to the data.
What makes the excess so interesting is that its features seem consistent with predictions from models of dark matter annihilation.