For question about this experiment and not covered in the following user guide, you can mail d2am.


Overview of the experiment.

The material science diffractometer is a general purpose instrument which was designed to record intensities over a wide dynamical range. It consists in a kappa goniometer  allowing users to record data in and out of the polarization plane. The whole instrument lies on a table used for its alignment.

kappa_goniometer

   
   

 

  • The sample can be oriented through 4 circles of the instrument which can be defined both as physical axis or virtual Eulerian ones:
    1. MU : sample rotation around a vertical axis (z).
    2. ETA - virtual eulerian angle : sample rotation around a horizontal axis perpendicular to the incident beam (y).
    3. CHI - virtual eulerian angle: sample rotation around x, it is carried by THETA. On figure 1 chi=90.
    4. PHI - virtual eulerian angle: sample rotation around the sample normal. It is carried by CHI and THETA, so that the sample lies horizontal at chi=90 (its normal is z) and vertical at chi=0 (its normal is then y). Note that at CHI=0, ETA and PHI axis are parallel and horizontal.
    5. KETA : physical rotation associated with ETA
    6. KAPP : physical rotation around the Kappa axis.
    7. KPHI : physical rotation associated with PHI

 

kappa_goniometer_head

  • The detection line uses  2 circles :
    1. NU : horizontal motion of the detector arm to allow measurement out of the polarization plane, its full use needs a special configuration of the experiment control program.
    2. DEL : vertical motion of the detector arm. It is carried by NU.

 

kappa_goniometer_detector

  • An optional 3 circles analyzer can be used

 

analyseur

top of page

 

Sample environments available :

  • A simple x,y,z-motorized sample holder. At room temperature, a vacuum chamber with a 80mm diameter Be hemisphere can be used to reduce the sources of diffusion, still allowing a wide access to the reciprocal space

 

weeding_cake

  • A heavy huber goniometer head allowing grazing incidence provide 2 circles ROY and ROX carrying 2 translation TOX and TOY, can be mounted. Its allows to keep a good confusion sphere (less than 40 microns ).

 

huber_stack