Analytic Models of Super-Eddington Accretion Discs (slim Discs, Polish Doughnuts)
The theory of highly super-Eddington black hole accretion, M>>MEdd, was developed in the 1980s by Abramowicz, Jaroszynski, Paczyński, Sikora and others in terms of "Polish doughnuts" (the name was coined by Rees). Polish doughnuts are low viscosity, optically thick, radiation pressure supported accretion discs cooled by advection. They are radiatively very inefficient. Polish doughnuts resemble in shape a fat torus (a doughnut) with two narrow funnels along the rotation axis. The funnels collimate the radiation into beams with highly super-Eddington luminosities.
Slim discs (name coined by Kolakowska) have only moderately super-Eddington accretion rates, M≥MEdd, rather disc-like shapes, and almost thermal spectra. They are cooled by advection, and are radiatively ineffective. They were introduced by Abramowicz, Lasota, Czerny and Szuszkiewicz in 1988.
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