Last modified: December 2023

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

xsvmcflow

Context: models

Synopsis

The XSPEC vmcflow model: cooling flow, mekal.

Syntax

xsvmcflow

The xsvmcflow model is an additive model component.

Description

The model is described at [1] . The results of this model depend on the cosmology settings set with set_xscosmo .


Example

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

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

mdl
   Param        Type          Value          Min          Max      Units
   -----        ----          -----          ---          ---      -----
   mdl.lowT     thawed          0.1       0.0808         79.9        keV
   mdl.highT    thawed            4       0.0808         79.9        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.Na       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           10           
   mdl.switch   frozen            1 -3.40282e+38  3.40282e+38           
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

Attribute Definition
lowT The minimum temperature, in keV.
highT The maximum temperature, in keV.
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 mass accretion rate (solar mass per year).

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
xsmkcflow