Last modified: December 2020

URL: https://cxc.cfa.harvard.edu/sherpa/ahelp/xscflux.html
AHELP for CIAO 4.13 Sherpa v1

xscflux

Context: models

Synopsis

The XSPEC cflux convolution model: calculate flux

Syntax

xscflux

The xscflux model is a convolution model component.

Description

The model is described at [1] .


Examples

Example 1

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.Emin     frozen          0.5            0        1e+06        keV
   mdl.Emax     frozen           10            0        1e+06        keV
   mdl.lg10Flux thawed          -12         -100          100        cgs

Example 2

With the following definitions:

>>> xscflux.cflux
>>> xsphabs.absmdl
>>> xspowerlaw.plmdl
>>> xsgaussian.gmdl
>>> srcmdl = plmdl + gmdl

then the model can be applied in a number of ways, such as:

>>> mdl1 = cflux(absmdl * srcmdl)
>>> mdl2 = absmdl * cflux(srcmdl)
>>> mdl3 = absmdl * (plmdl + cflux(gmdl))

ATTRIBUTES

The attributes for this object are:

Attribute Definition
Emin Minimum energy over which the flux is calculated.
Emax Maximum energy over which the flux is calculated.
lg10Flux log (base 10) of the flux in erg/cm^2/s

Notes

Unlike XSPEC, the convolution model is applied directly to the model, or models, rather than using the multiplication symbol.

See [1] for the meaning and restrictions, in particular the necessity of freezing the amplitude, or normalization, of the emission component (or components) at 1.

References

Changes in CIAO

Added in CIAO 4.13

XSPEC version

CIAO 4.13 comes with support for version 12.10.1s of the XSPEC models. This can be checked with the following:

% python -c 'from sherpa.astro import xspec;
print(xspec.get_xsversion())'
12.10.1s

Bugs

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

See Also

models
xsclumin, xscpflux