    The XSPEC bwcycl model: Becker-Wolff self-consistent cyclotron line model.

xsbwcycl
The xsbwcycl model is an additive model component.

The model is described at [1] . Please review the restrictions on the model and parameter values at this reference before using the model.

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

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

mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.Radius frozen 10 5 20 km mdl.Mass frozen 1.4 1 3 Solar mdl.csi thawed 3 0.01 20 mdl.delta thawed 1 0.01 20 mdl.B thawed 4 0.01 100 1e12G mdl.Mdot thawed 1 1e-06 1e+06 1e17g/s mdl.Te thawed 5 1.3 100 keV mdl.r0 thawed 44 10 1000 m mdl.D frozen 5 1 20 kpc mdl.BBnorm frozen 0 0 100 mdl.CYCnorm frozen 1 -1 100 mdl.FFnorm frozen 1 -1 100 mdl.norm frozen 1 0 1e+24

ATTRIBUTES

The attributes for this object are:

Attribute
Definition
Radius
The radius of the Neutron star, in km. Keep frozen.
Mass
The mass of the Neutron star, in solar units. Keep frozen.
csi
Parameter linked to the photon escape time (order of some unities).
delta
Ratio between bulk and thermal Comptonization importances.
B
The magnetic field in units of 10^12 G.
Mdot
The mass accretion rate, in 10^17 g/s.
Te
The electron temperature in units of keV.
r0
The column radius in m.
D
The source distance in kpc. Keep frozen.
BBnorm
The normalization of the blackbody seed photon component (fix it to zero at first).
CYCnorm
The normalization of the cyclotron emission seed photon component (fix it to one).
FFnorm
The normalization of the Bremsstrahlung emission seed photon component (fix it to one).
norm
The normalization of the model (fix it to one).

References

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

Changes in CIAO

The D parameter now displays the correct units (kpc) rather than km.

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