Synopsis
The XSPEC kerrbb model: multi-temperature blackbody model for thin accretion disk around a Kerr black hole.
Syntax
xskerrbb The xskerrbb model is an additive model component.
Description
The model is described at [1] .
Example
>>> create_model_component("xskerrbb", "mdl")
>>> print(mdl)Create a component of the xskerrbb model and display its default parameters. The output is:
mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.eta frozen 0 0 1 mdl.a thawed 0 -1 0.9999 mdl.i frozen 30 0 85 deg mdl.Mbh thawed 1 0 100 Msun mdl.Mdd thawed 1 0 1000 Mdd0 mdl.Dbh frozen 10 0 10000 kpc mdl.hd frozen 1.7 1 10 mdl.rflag frozen 1 -3.40282e+38 3.40282e+38 mdl.lflag frozen 0 -3.40282e+38 3.40282e+38 mdl.norm thawed 1 0 1e+24
ATTRIBUTES
The attributes for this object are:
| Attribute | Definition |
|---|---|
| eta | The ratio of the disk power produced by a torque at the disk inner boundary to the disk power arising from accretion. See [1] for more details. |
| a | The specific angular momentum of the black hole in units of the black hole mass M (when G=c=1). It should be in the range [-1, 1). |
| i | The disk inclination angle, in degrees. A face-on disk has i=0. It must be less than or equal to 85 degrees. |
| Mbh | The mass of the black hole, in solar masses. |
| Mdd | The "effective" mass accretion rate in units of 10^18 g/s. See [1] for more details. |
| Dbh | The distance from the observer to the black hole, in units of kpc. |
| hd | The spectral hardening factor, Tcol/Teff. See [1] for more details. |
| rflag | A flag to switch on or off the effect of self irradiation: when greater than zero the self irradition is included, otherwise it is not. This parameter can not be thawed. |
| lflag | A flag to switch on or off the effect of limb darkening: when greater than zero the disk emission is assumed to be limb darkened, otherwise it is isotropic. This parameter can not be thawed. |
| norm | The normalization of the model. It should be fixed to 1 if the inclination, mass, and distance are frozen. |
References
- [1] https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelKerrbb.html
XSPEC version
CIAO 4.17 comes with support for version 12.14.0k of the XSPEC models. This can be checked with the following:
% python -c 'from sherpa.astro import xspec; print(xspec.get_xsversion())' 12.14.0k
Bugs
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.