Recombination

class sherpa.astro.optical.Recombination(name='recombination')[source]

Bases: sherpa.models.model.ArithmeticModel

Optically-thin recombination continuum model.

It is for use when the independent axis is in Angstroms.

refer

The reference point, in Angstroms.

ampl

The amplitude of the emission; it is defined at the reference point but its numerical value there also depends on the temperature.

temperature

The temperature in Kelvin.

fwhm

The full-width half-maximum of the model in km/s.

Notes

The functional form of the model for points is:

f(x) = ampl * (refer / x)^2 *
       exp(-1.440E8 * (1 / x - 1 / refer) / temperature)

       if x < refer

     = ampl * exp(-0.5 * (x - refer)^2 / g(fwhm, refer)^2)

       otherwise

g(fwhm, refer) = refer * fwhm / (2.354820044 * c)

where c is the speed of light in km/s. For integrated data sets the low-edge of the grid is used.

Attributes Summary

thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars

Methods Summary

apply(outer, \*otherargs, \*\*otherkwargs)
calc(p, x[, xhi])
get_center()
guess(dep, \*args, \*\*kwargs) Set an initial guess for the parameter values.
reset()
set_center(\*args, \*\*kwargs)
startup()
teardown()

Attributes Documentation

thawedparhardmaxes
thawedparhardmins
thawedparmaxes
thawedparmins
thawedpars

Methods Documentation

apply(outer, *otherargs, **otherkwargs)
calc(p, x, xhi=None, **kwargs)[source]
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.

reset()
set_center(*args, **kwargs)
startup()
teardown()