Quasar Spectra Parameters

Black Hole Mass

Choose a black hole mass. The choices are an integer power of 2 times 10^9 solar masses.

Black Hole Spin

Choose either a nonrotating (Schwarzschild) black hole or a maximally rotating (a/m=0.998) Kerr black hole. At the moment, Schwarzschild models are only available for M=10^9 solar masses and alpha=0.01.

Disk Inclination

Choose the cosine of the observer viewing angle i, defined as the angle between the rotation axis of the disk and the observer line of sight. Small values of (cos i) correspond to near edge-on viewing, while large values correspond to near face-on viewing.

Accretion Rate Mdot

Choose a mass accretion rate through the disk. The choices are an integer power of 2 times 1 solar mass per year, for the case of a Kerr hole. In the case of a Schwarzschild hole, the choices are a power of 2 times 5.613 solar masses per year, in order to give the same set of values of the Eddington ratio.

Viscosity Parameter alpha

Choose between two values of the Shakura-Sunyaev viscosity parameter, alpha=0.01 or 0.1. Note that alpha=0.1 is not yet available for all models.

LTE vs. Non-LTE

Spectra have been calculated in the local thermodynamic equilibrium (LTE) approximation, and in full non-LTE. In the latter case the atomic level populations are calculated self-consistently with the local, ambient radiation field.

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