2021-01-08 11:00  P5A-1

Are the Fermi Bubbles Generated by Past Activity of the Galactic Center Black Hole?

Hsiang-Yi Karen Yang

Fermi bubbles, two giant gamma-ray bubbles extending 50 degrees above and below the Galactic center (GC), are one of the most important discoveries of the Fermi Gamma-ray Space Telescope. The energetics and symmetry about the GC suggest that they likely originate from powerful energy injections from the GC in the past, such as nuclear starburst or activity of the supermassive black hole. Because of the proximity, spatially resolved, multi-messenger data provide stringent constraints on the formation of the Fermi bubbles. For instance, the recently discovered "eRosita bubbles" in X-ray as well as the WMAP/Planck haze in microwave could all provide hints for their formation mechanisms. In this talk, I will review our current understanding of the origin of the Fermi bubbles, and present results from our 3D MHD plus cosmic-ray simulations of whether the Fermi bubbles could be inflated by past jet activity of the GC black hole.