Reflectivity and Advanced Scattering from Ordered Regimes (RASOR)

RASOR is a soft x-ray diffractomer, equipped with a full polarisation analyser, and low temperature capabilities. It is equipped with a Janis liquid helium cryostat enabling the sample to reach temperatures of 12 K.

Diffraction Circles

RASOR has two main rotation circles, theta for the sample and two theta for the detector, that both provide a full range of motion. In addition there is a chi rotation for the sample, however this is limited to +/- 4 deg. The sample position can be translated within these rotations by +/- 20mm perpendicular to the diffraction plane, and +/- 5mm crossed within the plane. A phi rotation (infinite range) can be added which rotates the sample about its surface normal. Note: this limits the lowest temperature that the sample can reach.

Detection

The scattered beam can be detected using a photodiode or a channeltron (a single channel electron multiplier).

The detector arm is equipped with a polarisation analyser. The polarisation analyser can be used with multilayers that are optimised specifically for each element of interest. These elements are K edges of O and Al and L_2,3 edges for Mn, Fe, Co, Ni and Cu.

Sample Mounts

There are a number of sample mounts available optimised for different use:

• Very low temperature
• Piezo rotation stage providing a phi rotation (this will compromise the lowest temperature attainable at sample position)

Most of the sample mounts allow multiple sample position, such that it is possible to mount a number of samples in the diffractometer simultaneously, and translate from one to the next.

Geometry