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            kerrbb: multi-temperature blackbody model for thin accretion disk around a Kerr black hole

A multi-temperature blackbody model for a thin, steady state, general relativistic accretion disk around a Kerr black hole. The effect of self-irradiation of the disk is considered, and the torque at the inner boundary of the disk is allowed to be non-zero. This model is intended as an extension to grad, which assumes that the black hole is non-rotating. For details see Li et al., ApJSuppl, 157, 335, 2005.

 

 par1   = eta, ratio of the disk power produced by a torque at the disk

          inner boundary to the disk power arising from accretion. It must

           be >= 0 and <=1. When eta = 0, the solution corresponds to that

          of a standard Keplerian disk with zero torque at the inner boundary.

 par2   = specific angular momentum of the black hole in units of the black

          hole mass M (geometrized units G=c=1). Should be >= -1 and < 1.

 par3   = disk's inclination angle (the angle between the axis of the disk

          and the line of sight). It is expressed in degrees. i=0 is for a

          "face-on" accretion disk. i should be <= 85 degree.

 par4   = the mass of the black hole in units of the solar mass.

 par5   = the "effective" mass accretion rate of the disk in units of

          10^18 g/sec. When eta = 0 (zero torque at the inner boundary),

          this is just the mass accretion rate of the disk. When eta is

          nonzero, the effective mass accretion rate = (1+eta) times

          the true mass accretion rate of the disk. The total disk

          luminosity is then "epsilon" times "the effective mass accretion

          rate" times "c^2", where epsilon is the radiation efficiency of a

          standard accretion disk around the Kerr black hole

 par6   = the distance from the observer to the black hole in units of kpc.

 par7   = spectral hardening factor, T_col/T_eff. It should be greater than

          1.0, and considered to be 1.5-1.9 for accretion disks around a

          stellar-mass black hole. See, e.g., Shimura and Takahara 1995,

          ApJ, 445, 780

 par8   = a flag to switch on/off the effect of self-irradiation (never

          allowed to be free). Self-irradiation is included when > 0.

          Self-irradiation is not included when <= 0.

 par9   = a flag to switch on/off the effect of limb-darkening (never

          allowed to be free). The disk emission is assumed to be

          limb-darkened when > 0. The disk emission is assumed

          to be isotropic when lflag is <= 0.

 K      = normalization.  Should be set to 1 if the inclination, mass and distance are frozen.


 

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Next: Kerrd Up: Additive Model Components Previous: Grbm