Astroparticle Seminar

Excess of Galactic Diffuse Gamma-ray Emission:
Astrophysics, Dark Mater, or Statistical Fluke

Meng Su

MIT

In this talk, I will first describe a pair of gigantic gamma-ray emitting bubbles — dubbed the Fermi bubbles we found recently using NASA's Fermi Gamma-ray Space Telescope. This double-bubble structure spans more than half of the visible sky and may be only a few million years old. It was most likely created as the remnant of a gigantic eruption of the super-massive black hole which sits in the Galactic center. By studying the bubbles from the inner Galaxy, there have been recent claims of a diffuse ~GeV excess extended up to ~20 degrees from the Galactic center, which can be explained by thermally produced WIMP annihilation. Finally, I will give an update about the recent claims of a gamma-ray line in the Galactic center at ~130 GeV.