Fermi Gamma-ray Space Telescope

The Fermi Bubbles as Pair Haloes

Demosthenes Kazanas
(Tonia Venters)


We propose that the relativistic electrons responsible for the gamma ray emission of the Fermi bubbles are the result of photon-photon interactions of high energy gamma rays, produced at an earlier active stage of the Galactic center black hole, with the ambient, lower energy photons of the Galaxy and the CMB. This explains the sharp gamma-ray contours of the Fermi bubbles and the dearth of lower energy radiation. It also provides an estimate of the "bubble" age at roughly 1 Myr.