    The XSPEC vvrnei model: non-equilibrium recombining collisional plasma.

xsvvrnei
The xsvvrnei model is an additive model component.

The model is described at [1] . The set_xsxset and get_xsxset

functions are used to set and query the XSPEC XSET parameters, in particular the keyword "NEIVERS".

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

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

mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.kT thawed 0.5 0.0808 79.9 keV mdl.kT_init thawed 1 0.0808 79.9 keV mdl.H frozen 1 0 1000 mdl.He frozen 1 0 1000 mdl.Li frozen 1 0 1000 mdl.Be frozen 1 0 1000 mdl.B frozen 1 0 1000 mdl.C frozen 1 0 1000 mdl.N frozen 1 0 1000 mdl.O frozen 1 0 1000 mdl.F 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.P frozen 1 0 1000 mdl.S frozen 1 0 1000 mdl.Cl frozen 1 0 1000 mdl.Ar frozen 1 0 1000 mdl.K frozen 1 0 1000 mdl.Ca frozen 1 0 1000 mdl.Sc frozen 1 0 1000 mdl.Ti frozen 1 0 1000 mdl.V frozen 1 0 1000 mdl.Cr frozen 1 0 1000 mdl.Mn frozen 1 0 1000 mdl.Fe frozen 1 0 1000 mdl.Co frozen 1 0 1000 mdl.Ni frozen 1 0 1000 mdl.Cu frozen 1 0 1000 mdl.Zn frozen 1 0 1000 mdl.Tau thawed 1e+11 1e+08 5e+13 s/cm^3 mdl.redshift frozen 0 -0.999 10 mdl.norm thawed 1 0 1e+24

ATTRIBUTES

The attributes for this object are:

Attribute
Definition
kT
The temperature of the plasma, in keV.
kT_init
The initial temperature of the plasma, in keV.
H
The H abundance: it should be set to 0 to switch on and 1 to switch off the free-free continuum.
He, Li, Be, B, C, N, O, F, Ne, Na, Mg, Al, Si, P, S, Cl, Ar, K, Ca, Sc, Ti, V, Cr, Mn, Fe, Co, Ni, Cu, Zn
The abundance of the element, with respect to Solar.
Tau
The ionization timescale in units of s/cm^3.
redshift
The redshift of the plasma.
norm
The normalization of the model: see [1] for an explanation of the units.

References

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

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

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

December 2023