Figure 7

Figure 7: The spectra emerging from geometrically thin accretion disks around black holes with different spins, but with the same accretion luminosity [41].From left to right, the curves correspond to spins (a ∕M) of 0, 0.2, 0.4, 0.6, 0.78, 0.881, 0.936, 0.966, and 0.99. The spin values were chosen to give roughly equal variation in the position of the spectral peak for spins > 0.8. The other parameters that determine the model are the viscosity parameter, α = 0.01, the inclination of the observer, cosi = 0.5, the mass of the black hole, M = 10M ⊙, and the accretion luminosity, L = 0.1LEdd. The peak energies of the spectra increase with increasing spin, as a consequence of the fact that the ISCO radius decreases with spin.