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  POLARISATION EFFECT

Simulates the effect of beam polarisation on Bragg diffracted intensities.

A graphical form is used to control the polarisation factor, the pixel sizes, the sample to detector distance, and the position of the direct beam on the detector. The detector is assumed to be orthogonal to the direct beam.

The polarisation factor is defined as $(I_h - I_v) / (I_h + I_v)$, where $I_h$ is the horizontal component and $I_v$ is the vertical component. (Horizontal should normally correspond to the X-direction of the image.)

Intensities in the ROI are reduced by the effect that the defined polarisation and geometry would produce.



Andrew Hammersley
2004-01-09