4-circle diffraction with a 3He dilution cryostat

In the four-circle mode, the offset C-shaped Eulerian cradle can be equipped with a helium-flow cryostat (1.6 K to 450 K, or 0.1 K to 10 K in dilution mode). This dilution cryostat is of an innovative design which allows it to work in any orientation and to follow all the movements of the diffractometer. A similar technique is used for satellite cryostats.

The movie shows the mounting of a new sample into the cryostat.

• the detector and the eulerian cradle are rotated to a position suitable for dismounting the previous sample
• the three vacuum/thermal shields of the cold head of the cryostat are removed to give access to the sample holder
• a new crystal (blue) is mounted and aligned
• a new indium vaccum seal is placed
• the three shields are re-mounted
• various cables, nitrogen & vacuum supply are disconnected or reconnected
• the diffractometer is ready to use in the four-circle mode for low temperature diffraction studies.