Last modified: December 2022

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

xscomptt

Context: models

Synopsis

The XSPEC compTT model: Comptonization, Titarchuk.

Syntax

xscomptt

The xscomptt model is an additive model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.redshift frozen            0       -0.999           10           
   mdl.T0       thawed          0.1        0.001          100        keV
   mdl.kT       thawed           50            2          500        keV
   mdl.taup     thawed            1         0.01          200           
   mdl.approx   frozen            1            0          200           
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
redshift The redshift of the source.
T0 The input soft photon (Wien) temperature in keV.
kT The plasma temperature, in keV.
taup The plasma optical depth.
approx The geometry setting: a value less than or equal to 1 is a disk, above 1 it is a sphere. See [1] for more details on how this parameter affects the model. It must remain frozen.
norm The normalization of the model.

References

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.