The XSPEC powerlaw model: power law photon spectrum.
xspowerlaw The xspowerlaw model is an additive model component.
The model is described at  .
>>> create_model_component("xspowerlaw", "mdl") >>> print(mdl)
Create a component of the xspowerlaw model and display its default parameters. The output is:
mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.PhoIndex thawed 1 -2 9 mdl.norm thawed 1 0 1e+24
The attributes for this object are:
The power law photon index.
The normalization of the model. See  for details, as its meaning depends on whether the "POW_EMIN" or "POW_EMAX" keywords have been set with set_xsxset .
-  https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelPowerlaw.html
CIAO 4.12 comes with support for version 12.10.1n of the XSPEC models. This can be checked with the following:
% python -c 'from sherpa.astro import xspec; print(xspec.get_xsversion())' 12.10.1n
See the bugs pages on the Sherpa website for an up-to-date listing of known bugs.