XScompth

class sherpa.astro.xspec.XScompth(name='compth')[source] [edit on github]

Bases: XSAdditiveModel

The XSPEC compth model: Paolo Coppi’s hybrid (thermal/non-thermal) hot plasma emission models.

The model is described at [1].

Note

Deprecated in Sherpa 4.10.0

The AbHe parameter has been renamed Ab_met to match the XSPEC definition. The name AbHe can still be used to access the parameter, but this name will be removed in a future release.

theta
showbb
kT_bb

The temperature of the blackbody if greater than 0. When less than zero then the absolute value is used as the T_max parameter of the XSdispkpn model. The units are in eV.

RefOn
tau_p

The Thomson scattering depth.

radius

The size of the scattering region in cm.

g_min

The minimum Lorentz factor of the pairs.

g_max

The maximum Lorentz factor of the pairs.

G_inj

If less than zero then the non-thermal spectrum is assumed mono-energetic at g_max, otherwise a power law is used from g_min to g_max.

pairinj

If zero then accelerated particles are electrons from thermal pool. If one then accelerated particles are electrons and positrons.

cosIncl

The cosine of the inclination angle of the reflecting material to the line of sight.

Refl

The fraction of the scattering region’s emission intercepted by reflecting material.

Fe_abund

The iron abundance with respect to solar.

Ab_met

The abundance of the other metals with respect to solar.

T_disk

The temperature of the reflecting disk, in K.

xi

The ionization parameter of the reflector.

Beta

The power-law index with radius of disk reflection emissivity.

Rin

The inner radius of the reflecting material, in units of GM/c^2.

Rout

The outer radius of the reflecting material, in units of GM/c^2.

redshift

The redshift of the source.

norm

The normalization of the model: see [1] for more details.

See also

XSeqpair, XSeqtherm

Notes

The precision of the numerical integration can be changed by using the set_xsxset function to set the value of the EQPAIR_PRECISION keyword, which defines the fractional precision. The default is 0.01 (1%).

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.

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.

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.

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
>>> from sherpa.utils import linear_interp
>>> 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.