The vacuum vessel - Experimental Hutch

Instrumentation

Air scattering can be one of the limitations in diffuse scattering experiments. To avoid this, one possibility is to perform such experiments under a complete vacuum in order to decrease the background to the lowest level possible. An evacuable hutch (p = 5 x 10^-3 Torr) has therefore been built for this purpose. It consists of a horizontal cylinder with a cover of 2.8 m diameter, which houses the diffractometer.

View of the vessel containing the diffractometer. The whole vessel and the SAXS nose containing the CCD camera can be pumped down to a pressure of 10-2 Torr in about 60 min.

The ID01 diffractometer. A full description can be found here.

An air lock system and a manipulator can be used to change samples without breaking the vacuum. The second part is a tube for SAXS experiments with a diameter of 100 cm which houses a Vacuum compatible CCD camera (Princeton). This detector tube can be closed and operated under vacuum, while the diffractometer chamber remains at atmospheric pressure. Moreover, a SAXS conical "nose" can be mounted close to the sample, reducing the air-scattering path to a few centimeters only, and still alowing the easy change of the sample (sample can be in air or in a small He-flow cell). In standard operation mode, 45 minutes will be sufficient to pump the whole vessel down to 10^-2 Torr pressure.

Standard equipment such as a furnace, cryostat, reaction cell or sample changer can be implemented on the diffractometer. Special user sample environments may be adapted through an interface plate, the drawing of which will be supplied on request. A room for sample preparation and a small workshop are located at the end of the beamline. There is also access to a machine workshop in the neighbouring Sect. 03. and a Surface Characterisation Laboratory.