Self-regulated accretion disks

We consider a class of fully self-gravitating accretion disks, for which efficient cooling mechanisms are assumed to maintain the disk close to the margin of Jeans instability. For such self-regulated disks, the equations become very simple in the outer regions, where the angular momentum convective transport approximately balances the viscous transport. These latter equations are shown to lead naturally to a self-similar solution with a flat rotation curve, with a circular velocity proportional to (M)(1/3) and an essentially fixed opening angle.