Pair production and annihilation in advective accretion disks around black holes

Sporadically Torqued Accretion Disks Around Black Holes

The assumption that black hole accretion disks possess an untorqued inner boundary, the so-called zero torque boundary condition, has been employed by models of black hole disks for many years. However, recent theoretical and observational work suggests that magnetic forces may appreciably torque the inner disk. This raises the question of the effect that a time-changing magnetic torque may hav...

Nucleosynthesis in Advective Accretion Disks around Galactic and Extra-galactic Black Holes

Many of the observational evidences for black hole rely on the fact that the incoming gas has the potential to become as hot as its virial temperature Tvirial ∼ 10 13 K (Rees, 1984). This flow is usually cooled down through bremsstrahlung and Comptonization effects and hard and soft states are produced depending on the degree by which this cooling takes place (Chakrabarti & Titarchuk, 1995). Th...

Computation of Mass-outflow Rates from Advective Accretion Disks around Black Holes

Physics Fundamentals of Luminous Accretion Disks around Black Holes

These lectures provide an overview of the theory of accretion disks with application to bright sources containing black holes. I focus on the fundamental physics of these flows, stressing modern developments and outstanding questions wherever possible. After a review of standard Shakura-Sunyaev based models and their problems and uncertainties, I describe the basic principles that determine the...

Neutrino-cooled Accretion Disks around Spinning Black Holes

Abstract. We calculate the structure of accretion disk around a spinning black hole for accretion rates Ṁ = 0.01− 10M⊙ s−1. The model is fully relativistic and treats accurately the disk microphysics including neutrino emissivity, opacity, electron degeneracy, and nuclear composition. We find that the accretion flow always regulates itself to a mildly degenerate state with the protonto-nucleon ...