XScompmag

class sherpa.astro.xspec.XScompmag(name='compmag')

Bases: sherpa.astro.xspec.XSAdditiveModel

The XSPEC compmag model: Thermal and bulk Comptonization for cylindrical accretion onto the polar cap of a magnetized neutron star.

The model is described at 1.

kTbb

The seed blackbody temperature, in keV.

kTe

The electron temperature of the accretion column, in keV.

tau

The vertical optical depth of the accretion column, with electron cross-section equal to 10^-3 of the Thomson cross-section.

eta

The index of the velocity profile when the accretion velocity increases towards the neutron star (valid when betaflag is 1).

beta0

The terminal velocity of the accreting matter at the neutron star surface (valid when betaflag is 1).

r0

The radius of the accretion column in units of the neutron star Schwarzschild radius.

A

The albedo at the surface of the neutron star.

betaflag

A flag for setting the velocity profile of the accretion column, described at 1. It has values of 1 or 2 and can not be thawed.

norm

The normalization of the model: see 1 for an explanation of the units.

References

1(1,2,3)

https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelCompmag.html

Attributes Summary

ndim
thawedparhardmaxes	The hard maximum values for the thawed parameters.
thawedparhardmins	The hard minimum values for the thawed parameters.
thawedparmaxes	Access to the maximum limits for the thawed parameters
thawedparmins	Access to the minimum limits for the thawed parameters
thawedpars	Access to the thawed parameters of the model
version_enabled

Methods Summary

apply(outer, *otherargs, **otherkwargs)
calc(pars, xlo, *args, **kwargs)	Evaluate the model on a grid.
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.

Attributes Documentation

ndim = 1

thawedparhardmaxes

The hard maximum values for the thawed parameters.

thawedparhardmins

The hard minimum values for the thawed parameters.

thawedparmaxes

Access to the maximum limits for the thawed parameters

thawedparmins

Access to the minimum limits for the thawed parameters

thawedpars

Access to the thawed parameters of the model

version_enabled = True

Methods Documentation

apply(outer, *otherargs, **otherkwargs)

calc(pars, xlo, *args, **kwargs)

Evaluate the model on a grid.

Parameters

• p (sequence of numbers) – The parameter values to use. The order matches the pars field.

• *args – The model grid. The values can be scalar or arrays, and the number depends on the dimensionality of the model and whether it is being evaluated over an integrated grid or at a point (or points).

get_center()

guess(dep, *args, **kwargs)

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)

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()

Reset the parameter values.

set_center(*args, **kwargs)

startup(cache=False)

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()

Called after a model may be evaluated multiple times.

See also

setup()