xsbkn2pow

Context: models

Synopsis

The XSPEC bkn2pow model: broken power law with two breaks.

Syntax

xsbkn2pow

The xsbkn2pow model is an additive model component.

Description

The model is described at [1] .

Example

>>> create_model_component("xsbkn2pow", "mdl")
>>> print(mdl)

Create a component of the xsbkn2pow model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.PhoIndx1 thawed            1           -3           10           
   mdl.BreakE1  thawed            5            0        1e+06        keV
   mdl.PhoIndx2 thawed            2           -3           10           
   mdl.BreakE2  thawed           10            0        1e+06        keV
   mdl.PhoIndx3 thawed            3           -3           10           
   mdl.norm     thawed            1            0        1e+24

ATTRIBUTES

The attributes for this object are:

Attribute	Definition
PhoIndx1	The power law photon index for energies less than BreakE1.
BreakE1	The first break energy, in keV.
PhoIndx2	The power law photon index for energies greater than BreakE1 but less than BreakE2.
BreakE2	The second break energy, in keV.
PhoIndx3	The power law photon index for energies greater than BreakE2.
norm	The normalization of the model. See [1] for details, as its meaning depends on whether the "POW_EMIN" or "POW_EMAX" keywords have been set with set_xsxset .

References

[1] https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelBkn2pow.html

XSPEC version

CIAO 4.17 comes with support for version 12.14.0k of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.14.0k

Bugs

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