Shielding for D007

The D007 shielding is composed by three main parts: - The monochomator tourelle; - The moustache; - The casemate. The function of these elements is to protect the environment from the neutrons scattered by the instrument components they cross. They are made put of steel and lead, partly machined and partly cast, and assembled toghetre to insure a tight construction. Some of the parts can be moved (blocs on the tourelle or doors on the casemate), the control of these element is not part of the tender. In particular, the movement of the blocks will be insured by electric drives and guide systems; it will be detected by switches positioned at the top and bottom of every bloc. Most of the shielding elements have to be shaped and linked to neighboring elements in a way that no radiation leakages between blocs are possible in radial direction from the beam axis. The shape of the walls of neighboring shielding blocs should be ‘zig-zag’ (French: ‘chicane’). This principle has also to be respected at the interfaces between all the elements. The moustache allows the link between the trourelle and the secondary spectrometer, making sure that during the rotation movement and the opening of the moving blocs, no direct view of the monochromator is possible. It is made out of lead and it integrates the instrument beam shutter (out of scope). Upstream from the tourelle lays the casemate, made out of a steel support structure holding lead panels for the walls and roof, and equipped with two doors.