Last modified: December 2018

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

xslyman

Context: models

Synopsis

The XSPEC lyman model: Voigt absorption profiles for H I or He II Lyman series.

Syntax

xslyman

The xslyman model is a multiplivative model component.

Description

The model is described at [1] .

Deprecated in Sherpa 4.10.0

The nHeI and redshift parameters have been renamed to n and z respectively to match the XSPEC definition. The names nHeI and redshift can still be used to access the parameters, but they will be removed in a future release.


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.n        thawed        1e-05            0        1e+06 10^22 atoms / cm^2
   mdl.b        thawed           10            1       100000       km/s
   mdl.z        thawed            0       -0.001       100000           
   mdl.ZA       thawed            1            1            2           

ATTRIBUTES

The attributes for this object are:

n

The H I or He II column density, in 10^22 atoms/cm^2.

b

The b value, in km/s.

z

The redshift of the absorber.

ZA

The atomic number of the species being calculated.

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
xsheilin