Vol. 587
In section 2. Astrophysical processes

The slimming effect of advection on black-hole accretion flows

Advective energy transport at very high-mass accretion rates affects the structure of the accretion disks. When radiation pressure dominates the structure of the inner disks of accreting compact objects, there are two possible states, either an optically thick but comparatively compressed disk (slim disks that the paper refers to for advection-dominated accretion flows) and optically thin, so-called ADAF models that also have thin disk solutions. The authors provide a clear exposition of the general properties of the physics, especially the stability, of these disks and present comparisons to state-of-the-art, fully relativistic MHD simulations to show that the transition to a thick disk, complete with internal funnel, does not occur. Since the latter model is the dominant picture for launching jets from luminous (super-Eddington) accretion flows, some major modifications are needed for the current scenario.