A combined radial collimator and cooled beryllium filter for neutron scattering

A flexible, combined, radial collimator and beryllium (Be) filter have been designed and manufactured at the Paul Scherrer Institut (PSI), Switzerland. The Be is integrated in the radial collimator by placing thin Be slices between the collimator lamellas. The filter/collimator is mounted within a vacuum vessel and dry cooled. The flexible design allows for different degrees of collimation and for different Be lengths. Results of measurements carried out at the BOA beamline at PSI are presented. These experiments include rotation scans determining the focal full width half maximum (FWHM), transmission measurements, test of different collimator lamellas and performance tests of the cooling of the filter. This new combined device will be a crucial part of the CAMEA spectrometer at SINQ, PSI.