<?xml version="1.0"?>
<!--
URL:
Editor: Mark Koennecke <Mark.Koennecke@psi.ch>
version: October 2006
$Id$

Instrument definition for a single crystal diffractometer at a monochromatic
neutron or X-ray beam.  This is the single detector version.

General Notes:
 - A Eulerian cradle is assumed. If you do not have this, or you are
   using a rotation camera, feel free to adapt the Nxsample group. 
 - If you put measurements for multiple reflections in one file, they 
   should go into separate entries.
 - The definition assumes the measurement to be an omega - two-theta or 
   omega scan of a given reflection. If this is not the case,  i.e. a 
   general scan is performed, feel free to make HKL, chi and phi arrays
   with the length of the scan as a dimension. As the  NeXus scan 
   paradigm of the day requires.
- This definition is fairly minimal and shall cater for standard data
  reduction needs. If your most favourite items are missing, feel free to
  add them. If you think something is missing which is required for standard
  data reduction tasks, please contact the maintainer of this definition.
- NP is again the number of scan points.
-->
<NXroot >
  <NXentry name="{Entry Name}">+
     <title type="NX_CHAR">{Title of the experiment}</title>
     <start_time type="ISO8601">{start time of measurement}
     </start_time>
     </end_time>
     <NXinstrument name="instrument">
        <NXcrystal name="{Name of Monochromator Crystal}">
       <wavelength type="NX_FLOAT32" units="Angstroems">
               {nominal wavelength selected}
           </wavelength>
        </NXcrystal>
        <NXdetector name="{Name of Detector}">+
       <polar_angle type="NX_FLOAT32[np]" axis="1">
             {Polar Angle, commonly known as two theta}
             {Polar Angle, or two theta as an array with values for each
              detector element}
           </polar_angle>
       <data type="NX_INT32[np]" signal="1" axes="polar_angle">
          {The counts detected in the detector}
       </data>
        </NXdetector>
     </NXinstrument>
     <NXmonitor name="control">
        <mode type="NX_CHAR">monitor | timer</mode>
        <preset type="NX_FLOAT32">
          {preset value for monitor or timer}
        </preset>
        <data type="NX_INT32">
          {Monitor counts}
        </data>
     </NXmonitor>
   <NXsample name="{Name of Sample}">
     <name type="NX_CHAR">
      {Descriptive name of sample}
     </name>
     <rotation type="NX_FLOAT[np]" units="degree">
        { Sample rotation, aslo known as omega }
     </rotation>
     <chi type="NX_FLOAT[np]" units="degree">
        { chi angle }
     </chi>
     <phi type="NX_FLOAT[np]" units="degree">
        { phi angle }
     </phi>
     <orientation_matrix type="NX_FLOAT32[3,3]">
       {Orientation matrix of single crystal according to conventions
        established by Busing,  Levy, 1967 }
      </orientation_matrix>
      <miller_indices type="NX_FLOAT[3]">
       { Miller indices of the target reflection}
      </miller_indices>
   </NXsample>
   <NXdata name="{Name of Data Block}">+
      <data type="NX_INT32[np]" signal="1">
         {Link to detector counts in NXdetector}
      </data>
      <polar_angle type="NX_FLOAT32[np]" axis="1">
         {Link to polar angle data in NXdetector}
      </polar_angle>
   </NXdata>
  </NXentry>
</NXroot>