Last modified: December 2018

URL: http://cxc.harvard.edu/sherpa/ahelp/xsc6pvmkl.html
AHELP for CIAO 4.11 Sherpa v1

xsc6pvmkl

Context: models

Synopsis

The XSPEC c6pvmkl model: differential emission measure using Chebyshev representations with multi-temperature mekal.

Syntax

xsc6pvmkl

The xsc6pvmkl model is an additive model component.

Description

The model is described at [1] . It differs from XSc6vmekl by by using the exponential of the 6th order Chebyshev polynomial.


Example

>>> create_model_component("xsc6pvmkl", "mdl")
>>> print(mdl)

Create a component of the xsc6pvmkl model and display its default parameters. The output is:

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.CPcoef1  thawed            1           -1            1           
   mdl.CPcoef2  thawed          0.5           -1            1           
   mdl.CPcoef3  thawed          0.5           -1            1           
   mdl.CPcoef4  thawed          0.5           -1            1           
   mdl.CPcoef5  thawed          0.5           -1            1           
   mdl.CPcoef6  thawed          0.5           -1            1           
   mdl.nH       frozen            1        1e-05        1e+19      cm^-3
   mdl.He       frozen            1            0           10           
   mdl.C        frozen            1            0           10           
   mdl.N        frozen            1            0           10           
   mdl.O        frozen            1            0           10           
   mdl.Ne       frozen            1            0           10           
   mdl.Na       frozen            1            0           10           
   mdl.Mg       frozen            1            0           10           
   mdl.Al       frozen            1            0           10           
   mdl.Si       frozen            1            0           10           
   mdl.S        frozen            1            0           10           
   mdl.Ar       frozen            1            0           10           
   mdl.Ca       frozen            1            0           10           
   mdl.Fe       frozen            1            0           10           
   mdl.Ni       frozen            1            0           10           
   mdl.redshift frozen            0       -0.999           10           
   mdl.switch   frozen            1            0            2           
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

CPcoef1, CPcoef2, CPcoef3, CPcoef4, CPcoef5, CPcoef6

Chebyshev polynomial coefficients.

nH

H density, in cm^-3.

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

The abundance relative to Solar.

redshift

The redshift of the plasma.

switch

If 0, the mekal code is run to evaluate the model; if 1 then interpolation of the mekal data is used; if 2 then interpolation of APEC data is used. See [1] for more details. This parameter can not be thawed.

norm

The normalization of the model.

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
xsc6mekl, xsc6pmekl, xsc6vmekl