Last modified: December 2023

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/xspwab.html
AHELP for CIAO 4.16 Sherpa

xspwab

Context: models

Synopsis

The XSPEC pwab model: power-law distribution of neutral absorbers.

Syntax

xspwab

The xspwab model is a multiplicative model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.nHmin    thawed            1        1e-07        1e+06 10^22 atoms / cm^2
   mdl.nHmax    thawed            2        1e-07        1e+06 10^22 atoms / cm^2
   mdl.beta     frozen            1          -10           20           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
nHmin The minimum equivalent hydrogen column (in units of 10^22 atoms/cm^2).
nHmax The maximum equivalent hydrogen column (in units of 10^22 atoms/cm^2).
beta The power law index for the covering fraction.

References

XSPEC version

CIAO 4.16 comes with support for version 12.13.1e of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.13.1e

Bugs

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

See Also

models
xspcfabs, xszxipab