Photoabsorption edge model.
This model can be used when the independent axis is in energy or wavelength space.
>>> create_model_component("edge", "mdl") >>> print(mdl)
Create a component of the edge model and display its default parameters. The output is:
mdl Param Type Value Min Max Units ----- ---- ----- --- --- ----- mdl.space thawed 0 0 1 0 - energy | 1 - wave mdl.thresh thawed 1 0 3.40282e+38 mdl.abs thawed 1 0 3.40282e+38
The attributes for this object are:
Switch to select whether the independent axis is energy or wavelength. This parameter is not fit ( alwaysfrozen is set), and should be set to either 0, when the independent axis is energy with units of keV, or 1 when the axis is wavelength with units of Angstrom.
The edge position (in energy or wavelength units matching the data grid).
The absorption coefficient.
A phenomenological photoabsorption edge model as a function of energy:
f(x) = exp(-abs * (x / thresh)^-3) if x >= thresh = 1.0 otherwise
or, as a function of wavelength:
f(x) = exp(-abs * (x / thresh)^3) if x <= thresh = 1.0 otherwise
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