The specific angular momentum associated with eddies is $J \sim V_tk$ and the specific angular momentum of the accreted gas corresponds to eddies of the order of twice the scale of the capture impact parameter. Thus, the first condition for disk formation requires $$M > 720\left(\frac{u_{\infty}}{50~km.s^{-1}}\right)^4 ~M_\odot$$ whereas the second requires $$M < 3.5\times 10^6\left(\frac{u_{\infty}}{50~km.s^{-1}}\right)^3~ M_\odot$$ The conclusion of this brief analysis is that a disk can be formed after the shock front only if the BH mass is in the range $10^3$ up to $10^6$ $M_\odot$. Notice that these values depend strongly on the black hole velocity. Taking into account the restricted range of BH masses that allows the presence of a disk, the necessity of an adequate balance between the mass flow across the shock front and the flow throughout the disk that is controlled by viscous forces, as well as the variety of instabilities present in the flow after the shock. Under these conditions, the formation of a disk under these circumstances is rather uncertain. In this case, if a disk is not formed inside the accretion cone, the radiated luminosity is only a small fraction of the accretion power.

Intermittent Growth of Black Holes
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As 