Small-scale inviscid accretion discs around black holes

Gas falling quasi-spherically on to a black hole forms an inner accretion disc if its specific angular momentum l exceeds l∗∼rgc, where rg is the Schwarzschild radius. The standard disc model assumes l≫l∗. We argue that, in many black hole sources, accretion flows have angular momenta just above the threshold for disc formation, l≳l∗, and assess the accretion mechanism in this regime. In a range l∗