Accretion of multi-species plasma onto black holes

Matter falling onto a black hole is trans-relativistic, transonic, and close to the horizon it is sub-Keplerian. Such a flow shows the existence of multiple critical point, shocks etc. Employing relativistic equation of state and realistic composition, it has been shown that the solution strongly depend on the composition of the fluid. Electron-positron fluid is the least relativistic, to the extent that multiple critical points, shocks etc do not form. The most relativistic fluid is the one whose ratio of proton to electron number density is ~ 0.2. Since the solution strongly depend on composition, the emitted radiation should strongly depend on the composition too.