Last modified: December 2023

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

xszlogpar

Context: models

Synopsis

The XSPEC zlogpar model: log-parabolic blazar model.

Syntax

xszlogpar

The xszlogpar model is an additive model component.

Description

The model is described at [1] .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.alpha    thawed          1.5            0            4           
   mdl.beta     thawed          0.2           -4            4           
   mdl.pivotE   frozen            1 -3.40282e+38  3.40282e+38        keV
   mdl.Redshift frozen            0       -0.999           10           
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
alpha The slope at the pivot energy.
beta The curvature term.
pivotE The pivot energy, in keV.
Redshift The redshift.
norm The normalization of the model: see [1] for more details.

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
xslogpar