Whereabouts are you from?
asslick
The gamma ray radiation is produced by processes involving shock waves from material ejected by the black hole "engine" that was formed when the star collapsed. "Shells" of material traveling at different speeds -- all very close the the speed of light -- pile up on each other, like snow in front of a shovel, creating internal shocks that emit low-energy gamma rays. But the lead edge of the beam also collides with the interstellar medium, producing a massive external shock and emitting high-energy gamma rays, x-rays, visible light and other radiation, known as the afterglow.