.. index:: ComptonPeakProfile
The ComptonPeakProfile describes the Neutron Compton profile with either a Voigt or Gaussian approximation, depending on an energy cutoff value. It takes three input parameters:
- Intensity: I
- Position: P
- SigmaGauss: \sigma_G
and three attributes,
- WorkspaceIndex
- Mass
- VoigtEnergyCutOff
The VoigtEnergyCutOff is used to determine whether a Gaussian or Voigt function is used to fit the peak. If the final energy, as read from the input workspace, is greater than the VoigtEnergyCutOff a normalised Gaussian approximation is used,
\frac{I}{2\pi \sigma_T^2}\exp \left( -0.5*\frac{(x-P)^2}{\sigma_T^2} \right)
where \sigma_T^2 is the total variance, defined by
\sigma_T^2 = \sigma_G^2 + \Gamma^2
where \Gamma is the half-width-half-maximum, estimated from the input data.
If instead, the energy is below the cutoff an :ref:`approximation <func-Voigt>` to a Voigt function is used with the following inputs:
\text{LorentzAmp} = I
\text{LorentzPos} = P
\text{LorentzFWHM} = 2\Gamma
\text{GaussianFWHM}= 0.5 \sigma_G \sqrt{\ln(4)}
.. attributes::
.. properties::
.. categories::
.. sourcelink::