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Image CIF dictionary (imgCIF) version 3.00.04

_diffrn_scan_frame.polarizn_Stokes_U

Name:
_diffrn_scan_frame.polarizn_Stokes_U

Definition:

   
     (Ip-In)*sin(2*theta), where where Ip is the intensity
     (amplitude squared) of the electric vector in the plane of
     polarization, In is the intensity (amplitude squared) of
     the electric vector in the plane of the normal to the
     plane of polarization, and theta is the angle as viewed
     from the specimen, between the normal to the polarization
     plane and the laboratory Y axis as defined in the
     AXIS category.
     This is an average or other representative sample of the scan.  
     This is the third of the Stokes polarization parameters,
     I, Q, U, V (also known as I, M, C, S).  See
     H. H. Berry, G. Gabrielse, A. E. Livingston (1977),
     "Measurement of the Stokes parameters of Light",
     Applied Optics, 16:12, 3200 -- 3205.
     If the absolute intensity is not known, the value 1.
     is assumed for I, and all 4 Stokes parameters are
     dimensionless.  When the absolute intensity is known,
     all 4 Stokes parameters are in units of Watts per
     square meter.

Type: Real

Category:
diffrn_scan_frame