Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/xsvphabs.html
AHELP for CIAO 4.11 Sherpa v1

xsvphabs

Context: models

Synopsis

The XSPEC vphabs model: photoelectric absorption.

Syntax

xsvphabs

The xsvphabs model is a multiplivative model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.nH       thawed            1            0       100000 10^22 atoms / cm^2
   mdl.He       frozen            1            0         1000           
   mdl.C        frozen            1            0         1000           
   mdl.N        frozen            1            0         1000           
   mdl.O        frozen            1            0         1000           
   mdl.Ne       frozen            1            0         1000           
   mdl.Na       frozen            1            0         1000           
   mdl.Mg       frozen            1            0         1000           
   mdl.Al       frozen            1            0         1000           
   mdl.Si       frozen            1            0         1000           
   mdl.S        frozen            1            0         1000           
   mdl.Cl       frozen            1            0         1000           
   mdl.Ar       frozen            1            0         1000           
   mdl.Ca       frozen            1            0         1000           
   mdl.Cr       frozen            1            0         1000           
   mdl.Fe       frozen            1            0         1000           
   mdl.Co       frozen            1            0         1000           
   mdl.Ni       frozen            1            0         1000           

ATTRIBUTES

The attributes for this object are:

nH

The equivalent hydrogen column (in units of 10^22 atoms/cm^2).

He, C, N, O, Ne, Na, Mg, Al, Si, S, Cl, Ar, Ca, Cr, Fe, Co, Ni

The abundance of the element in solar units.

Notes

The `set_xsxsect` function changes the cross sections used by this model. The `set_xsabund` function changes the relative abundances of the elements.

References

XSPEC version

CIAO 4.11 comes with support for version 12.10.0e of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.10.0e

Bugs

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

See Also

models
xsphabs, xsvarabs, xszphabs, xszvphabs