Excess of Diffuse Gamma-ray Emission from the Inner Galaxy: Bubbles, Jets, and Dark Matter
I will first talk about the discovery of a pair of gigantic bubbles in our Galaxy
using data from Fermi Gamma-ray Space Telescope, and the multi-wavelength
observations on this so called "Fermi bubble" structure. Our numerical simulation
demonstrates that the bubble structure could be evidence for past accretion events
of the central supermassive black hole. I will then summarize the current state of dark
matter search with Fermi data, with the focus on gamma-ray line searching from the
Galactic center, galaxy clusters, and dwarf galaxies. I will explain why we got extremely
excited in 2012 with a tentative gamma-ray line signal from the Galactic center. We have
recently proposed to change the survey strategy of Fermi to increase the exposure at
the Galactic center by more than a factor of 2. This new survey strategy has been
initiated since December 2013 and will last for at least one year. I will end up with a
discussion of future gamma-ray space missions.