XSbwcycl

class sherpa.astro.xspec.XSbwcycl(name='bwcycl')[source] [edit on github]

Bases: XSAdditiveModel

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

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

Changed in version 4.14.0: The D parameter now displays the correct units (kpc) rather than km.

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

Attributes Summary

`cache`	The maximum size of the cache.
`ndim`	A one-dimensional model.
`thawedparhardmaxes`	The hard maximum values for the thawed parameters.
`thawedparhardmins`	The hard minimum values for the thawed parameters.
`thawedparmaxes`	The maximum limits of the thawed parameters.
`thawedparmins`	The minimum limits of the thawed parameters.
`thawedpars`	The thawed parameters of the model.
`version_enabled`

Methods Summary

`apply`(outer, otherargs, *otherkwargs)
`cache_clear`()	Clear the cache.
`cache_status`()	Display the cache status.
`calc`(p, args, *kwargs)	Calculate the model given the parameters and grid.
`freeze`()	Freeze any thawed parameters of the model.
`get_center`()
`guess`(dep, args, *kwargs)	Set an initial guess for the parameter values.
`regrid`(args, *kwargs)	The class RegriddableModel1D allows the user to evaluate in the requested space then interpolate onto the data space.
`reset`()	Reset the parameter values.
`set_center`(args, *kwargs)
`startup`([cache])	Called before a model may be evaluated multiple times.
`teardown`()	Called after a model may be evaluated multiple times.
`thaw`()	Thaw any frozen parameters of the model.

Attributes Documentation

cache = 5: The maximum size of the cache.

ndim = 1: A one-dimensional model.

thawedparhardmaxes

The hard maximum values for the thawed parameters.

The minimum and maximum range of the parameters can be changed with thawedparmins and thawedparmaxes but only within the range given by thawedparhardmins to thawparhardmaxes.

See also

thawedparhardmins, thawedparmaxes

thawedparhardmins

The hard minimum values for the thawed parameters.

The minimum and maximum range of the parameters can be changed with thawedparmins and thawedparmaxes but only within the range given by thawedparhardmins to thawparhardmaxes.

See also

thawedparhardmaxes, thawedparmins

thawedparmaxes

The maximum limits of the thawed parameters.

Get or set the maximum limits of the thawed parameters of the model as a list of numbers. If there are no thawed parameters then [] is used. The ordering matches that of the pars attribute.

See also

thawedpars, thawedarhardmaxes, thawedparmins

thawedparmins

The minimum limits of the thawed parameters.

Get or set the minimum limits of the thawed parameters of the model as a list of numbers. If there are no thawed parameters then [] is used. The ordering matches that of the pars attribute.

See also

thawedpars, thawedarhardmins, thawedparmaxes

thawedpars

The thawed parameters of the model.

Get or set the thawed parameters of the model as a list of numbers. If there are no thawed parameters then [] is used. The ordering matches that of the pars attribute.

See also

thawedparmaxes, thawedparmins

version_enabled = True

Methods Documentation

apply(outer, *otherargs, **otherkwargs) [edit on github]

cache_clear() [edit on github]: Clear the cache.

cache_status() [edit on github]

Display the cache status.

Information on the cache - the number of “hits”, “misses”, and “requests” - is displayed at the INFO logging level.

Example

>>> pl.cache_status()
 powlaw1d.pl                size:    5  hits:   633  misses:   240  check=  873

calc(p, *args, **kwargs) [edit on github]

Calculate the model given the parameters and grid.

Notes

XSPEC models must always be evaluated with low and high bin edges. Although supported by the XSPEC model interface the ability to evaluate using an XSPEC-style grid (n+1 values for n bins which we pad with a 0), we do not allow this here since it complicates the handling of the regrid method.

Keyword arguments are ignored.

freeze() [edit on github]: Freeze any thawed parameters of the model.

get_center() [edit on github]

guess(dep, *args, **kwargs) [edit on github]

Set an initial guess for the parameter values.

Attempt to set the parameter values, and ranges, for the model to match the data values. This is intended as a rough guess, so it is expected that the model is only evaluated a small number of times, if at all.

regrid(*args, **kwargs) [edit on github]

The class RegriddableModel1D allows the user to evaluate in the requested space then interpolate onto the data space. An optional argument ‘interp’ enables the user to change the interpolation method.

Examples

>>> import numpy as np
>>> from sherpa.models.basic import Box1D
>>> mybox = Box1D()
>>> request_space = np.arange(1, 10, 0.1)
>>> regrid_model = mybox.regrid(request_space, interp=linear_interp)

reset() [edit on github]

Reset the parameter values.

Restores each parameter to the last value it was set to. This allows the parameters to be easily reset after a fit.

set_center(*args, **kwargs) [edit on github]

startup(cache=False) [edit on github]

Called before a model may be evaluated multiple times.

Parameters:: cache (bool, optional) – Should a cache be used when evaluating the models.

See also

teardown

teardown() [edit on github]: Called after a model may be evaluated multiple times.

See also

startup

thaw() [edit on github]

Thaw any frozen parameters of the model.

Those parameters that are marked as “always frozen” are skipped.