Last modified: December 2018

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

xsbvrnei

Context: models

Synopsis

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

Syntax

xsbvrnei

The xsbvrnei model is an additive model component.

Description

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".


Example

>>> 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         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.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.Tau      thawed        1e+11        1e+08        5e+13     s/cm^3
   mdl.Redshift frozen            0       -0.999           10           
   mdl.Velocity frozen            0            0        1e+06       km/s
   mdl.norm     thawed            1            0        1e+24           

ATTRIBUTES

The attributes for this object are:

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.

New in CIAO 4.11

The xsbvrnei model (added in XSPEC 12.10.0) is new in CIAO 4.11

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
xsbrnei, xsbvvrnei