XSgrad¶

class sherpa.astro.xspec.XSgrad(name='grad')[source]¶

Bases: sherpa.astro.xspec.XSAdditiveModel

The XSPEC grad model: accretion disk, Schwarzschild black hole.

The model is described at [1].

Note

Deprecated in Sherpa 4.10.0

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

D¶: The distance to the source in kpc.

i¶: The disk inclination angle, in degrees. A face-on disk has i=0.

Mass¶: The mass of the central object, in solar masses.

Mdot¶: The mass accretion rate in units of 10^18 g/s.

TclovTef¶: The spectral hardening factor, Tcol/Teff. See [1] for more details.

refflag¶: A flag to control the relativistic effects: if positive then a relativistic calculation is used; if zero or negative then a Newtonian calculation is used. See [1] for more details. This parameter can not be thawed.

norm¶: The normalization of the model. It should be fixed to 1.

See also

XSkerbb

References

[1]	(1, 2, 3) https://heasarc.gsfc.nasa.gov/xanadu/xspec/manual/XSmodelGrad.html

Attributes Summary

`thawedparhardmaxes`
`thawedparhardmins`
`thawedparmaxes`
`thawedparmins`
`thawedpars`
`version_enabled`

Methods Summary

`apply`(outer, otherargs, *otherkwargs)
`calc`(pars, xlo, args, *kwargs)
`get_center`()
`guess`(dep, args, *kwargs)	Set an initial guess for the parameter values.
`regrid`(*arrays)
`reset`()
`set_center`(args, *kwargs)
`startup`()	Called before a model may be evaluated multiple times.
`teardown`()	Called after a model may be evaluated multiple times.

Attributes Documentation

thawedparhardmaxes¶

thawedparhardmins¶

thawedparmaxes¶

thawedparmins¶

thawedpars¶

version_enabled = True¶

Methods Documentation

apply(outer, *otherargs, **otherkwargs)¶

calc(pars, xlo, *args, **kwargs)¶

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(*arrays)¶

reset()¶

set_center(*args, **kwargs)¶

startup()¶: Called before a model may be evaluated multiple times.

See also

teardown()

teardown()¶: Called after a model may be evaluated multiple times.

See also

setup()