    The XSPEC bvrnei model: velocity-broadened non-equilibrium recombining collisional plasma.

xsbvrnei
The xsbvrnei 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("xsbvrnei", "mdl")
>>> print(mdl)

Create a component of the xsbvrnei 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 1 mdl.He frozen 1 0 10000 mdl.C frozen 1 0 10000 mdl.N frozen 1 0 10000 mdl.O frozen 1 0 10000 mdl.Ne frozen 1 0 10000 mdl.Mg frozen 1 0 10000 mdl.Si frozen 1 0 10000 mdl.S frozen 1 0 10000 mdl.Ar frozen 1 0 10000 mdl.Ca frozen 1 0 10000 mdl.Fe frozen 1 0 10000 mdl.Ni frozen 1 0 10000 mdl.Tau thawed 1e+11 1e+08 5e+13 s/cm^3 mdl.Redshift frozen 0 -0.999 10 mdl.Velocity frozen 0 0 10000 km/s 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, He, C, N, O, Ne, Mg, Si, S, Ar, Ca, Fe, Ni
The abundance of the element in solar units.
Tau
The ionization timescale in units of s/cm^3.
Redshift
The redshift of the plasma.
Velocity
The gaussian sigma of the velocity broadening, in km/s.
norm
The normalization of the model: see [1] for an explanation of the units.

References

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

Changes in CIAO

The maximum for the Velocity parameter has been changed from 10^6 to 10^4 km/s.

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