Super-Eddington black hole accretion: Polish doughnuts and slim disks

The theory of highly super-Eddington black hole accretion was developed in the 1980s in Warsaw by Paczynski and his collaborators in terms of "Polish doughnuts", i.e. low viscosity, rotating accretion flows that are optically thick, radiation pressure supported, cooled by advection, and radiatively very inefficient. Polish doughnuts resemble fat tori with two narrow funnels along rotation axis. The funnels collimate radiation into beams with highly super-Eddington luminosities. "Slim disks" introduced later by Abramowicz, Lasota and collaborators, have only moderately super-Eddington accretion rates, rather disk-like shapes, and almost thermal spectra.