| DRAFT DICTIONARY CBF/imgCIF Extensions Dictionary | Draft version 1.5 for comment | 
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Definition:
        Beam crossfire in degrees parallel to the laboratory X axis
               (see AXIS category).
               This is a characteristic of the X-ray beam as it illuminates
               the sample (or specimen) after all monochromation and
               collimation.
               This is the standard uncertainty (e.s.d.)  of the directions of
               photons in the XZ plane around the mean source beam
               direction.
               Note that for some synchrotrons this value is specified
               in milliradians, in which case a conversion is needed.
               To convert a value in milliradians to a value in degrees,
               multiply by 0.180 and divide by \p.
Type: float
Mandatory item: no
Category: diffrn_radiation
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