Last modified: December 2018

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

xsacisabs

Context: models

Synopsis

The XSPEC acisabs model: Chandra ACIS q.e. decay.

Syntax

xsacisabs

The xsacisabs model is a multiplivative model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.Tdays    frozen          850            0        10000       days
   mdl.norm     frozen      0.00722            0            1           
   mdl.tauinf   frozen        0.582            0            1           
   mdl.tefold   frozen          620            1        10000       days
   mdl.nC       frozen           10            0           50           
   mdl.nH       frozen           20            1           50           
   mdl.nO       frozen            2            0           50           
   mdl.nN       frozen            1            0           50           

ATTRIBUTES

The attributes for this object are:

Tdays

Days between Chandra launch and ACIS observation.

norm

tauinf

Slope of linear quantum efficiency decay.

tefold

Offset of linear quantum efficiency decay.

nC

Number of carbon atoms in hydrocarbon.

nH

Number of hydrogen atoms in hydrocarbon.

nO

Number of oxygen atoms in hydrocarbon.

nN

Number of nitrogen atoms in hydrocarbon.

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.