Last modified: December 2022

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/xssimpl.html
AHELP for CIAO 4.15 Sherpa

xssimpl

Context: models

Synopsis

The XSPEC simpl convolution model: comptonization of a seed spectrum.

Syntax

xssimpl

The xssimpl model is a convolution model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.Gamma    thawed          2.3            1            5           
   mdl.FracSctr thawed         0.05            0            1           
   mdl.UpScOnly frozen            1            0          100           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
Gamma The photon power law index.
FracSctr The scattered fraction (between 0 and 1).
UpScOnly A flag to switch between up-scattering only (when greater than zero) or both up- and down-scattering (when zero or less).

Notes

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

References

Changes in CIAO

Added in CIAO 4.13

XSPEC version

CIAO 4.15 comes with support for version 12.12.1c of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.12.1c

Bugs

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