Last modified: December 2021

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/xsthcomp.html
AHELP for CIAO 4.14 Sherpa

xsthcomp

Context: models

Synopsis

The XSPEC thcomp convolution model: Thermally comptonized continuum.

Syntax

xsthcomp

The xsthcomp model is a convolution model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.Gamma_tau thawed          1.7        1.001           10           
   mdl.kT_e     thawed           50          0.5          150        keV
   mdl.cov_frac thawed            1            0            1           
   mdl.z        frozen            0            0            5           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
Gamma_tau The low-energy power-law photon index when positive and the Thomson optical depth (multiplied by -1) when negative.
kT_e The electron temperature (high energy rollover)
cov_frac The scattering fraction (between 0 and 1). If 1 then all of the seed photons will be Comptonized, and if 0 then only the original seed photons will be seen.
z redshift

Notes

Unlike XSPEC, the convolution model is applied directly to the model, or models, rather than using the multiplication symbol.

References

Changes in CIAO

New in CIAO 4.14

The xsthcomp model (added in XSPEC 12.11.0) is new in CIAO 4.14.

XSPEC version

CIAO 4.14 comes with support for version 12.12.0 of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.12.0

Bugs

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

See Also

models
xsnthcomp