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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 (Ih - Iv) / (Ih + Iv), where Ih is the horizontal component and Iv is the vertical component. (Horizontal should normally correspond to the X-direction of the image.)

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



Andy Hammersley
8/26/1998