Last modified: December 2018

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

xsvapec

Context: models

Synopsis

The XSPEC vapec model: APEC emission spectrum.

Syntax

xsvapec

The xsvapec model is an additive model component.

Description

The model is described at [1] , with XSapec describing how it is implemented in Sherpa.


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.kT       thawed          6.5       0.0808       68.447        keV
   mdl.He       frozen            1            0         1000           
   mdl.C        frozen            1            0         1000           
   mdl.N        frozen            1            0         1000           
   mdl.O        frozen            1            0         1000           
   mdl.Ne       frozen            1            0         1000           
   mdl.Mg       frozen            1            0         1000           
   mdl.Al       frozen            1            0         1000           
   mdl.Si       frozen            1            0         1000           
   mdl.S        frozen            1            0         1000           
   mdl.Ar       frozen            1            0         1000           
   mdl.Ca       frozen            1            0         1000           
   mdl.Fe       frozen            1            0         1000           
   mdl.Ni       frozen            1            0         1000           
   mdl.redshift frozen            0       -0.999           10           
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

kT

The temperature of the plasma, in keV.

He, C, N, O, Ne, Mg, Al, Si, S, Ar, Ca, Fe, Ni

The abundance of the element in solar units.

redshift

The redshift of the plasma.

norm

The normalization of the model: see [1] for an explanation of the units.

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
xsapec, xsbapec, xsbvapec, xsbvvapec, xsvvapec