Last modified: December 2023

AHELP for CIAO 4.16 Sherpa


Context: models


The XSPEC slimbh model: Stationary slim accretion disk.



The xsslimbh model is an additive model component.


The model is described at [1] . The set_xsxset and get_xsxset functions are used to set and query the XSPEC XSET "SLIMBB_DEBUG", "SLIMBB_DIR", and "SLIMBB_TABLE" parameters.


>>> create_model_component("xsslimbh", "mdl")
>>> print(mdl)

Create a component of the xsslimbh model and display its default parameters. The output is:

   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.M        frozen           10            0         1000       Msun
   mdl.a        thawed            0            0        0.999       GM/c
   mdl.lumin    thawed          0.5         0.05            1      L_Edd
   mdl.alpha    frozen          0.1        0.005          0.1           frozen           60            0           85        deg
   mdl.D        frozen           10            0        10000        kpc
   mdl.f_hard   frozen           -1          -10           10           
   mdl.lflag    frozen            1 -3.40282e+38  3.40282e+38           
   mdl.vflag    frozen            1 -3.40282e+38  3.40282e+38           
   mdl.norm     frozen            1            0        1e+24           


The attributes for this object are:

Attribute Definition
M The mass of the black hole, in M_sol.
a The black hole spin parameter.
lumin The total disk luminosity in Eddington units.
alpha alpha-viscosity
inc The inclination, in degrees.
D The distance to the source, in kpc.
f_hard The hardening factor. A negative value means to use TLUSTY spectra.
lflag A flag to control the effect of limb-darkening. If greater than zero then the disk emission is limb-darkened, otherwise it is assumed to be isotropic.
vflag A flag to control the surface profile. If greater than zero, raytracing is done from the actual photosphere, otherwise the spectrum is raytraced from the equatorial plane ignoring the height profile of the disk.
norm The normalization of the model: see [1] for an explanation of the units.


XSPEC version

CIAO 4.16 comes with support for version 12.13.1e of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;


See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.