Last modified: December 2022

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

xszbabs

Context: models

Synopsis

The XSPEC zbabs model: EUV ISM attenuation.

Syntax

xszbabs

The xszbabs model is a multiplicative model component.

Description

The model is described at [1] .

Deprecated in Sherpa 4.10.0

The redshift parameter has been renamed z to match the XSPEC definition. The name redshift can still be used to access the parameter, but this name will be removed in a future release.


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.nH       thawed       0.0001            0        1e+06 10^22 atoms / cm^2
   mdl.nHeI     thawed        1e-05            0        1e+06 10^22 atoms / cm^2
   mdl.nHeII    thawed        1e-06            0        1e+06 10^22 atoms / cm^2
   mdl.z        thawed            0            0        1e+06           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
nH The H column density, in 10^22 atoms/cm^2.
nHeI The He I column density, in 10^22 atoms/cm^2.
nHeII The He II column density, in 10^22 atoms/cm^2.
z The redshift of the absorber.

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.