KWS 2 High Intensity / Wide-Q
Small Angle Neutron Diffractometer

- the flux (measurements Summer 2007 for a CS filling of 10.6l):

(higher flux achieved for a better CS filling - nominal volume 15l)

- monochromatization: Astrium velocity selector 20% wavelength smearing (additional two-discs chopper planned to be installed in Summer 2009)

- the actual Q-range (with max. 8m detection range):

(the nominal Q range - between 0.002 and 0.2 1/Angstroem - achieved by using only 7 Angstroem neutrons will be possible after the installation of the entire detection range, up to 20m - Summer 2009)

- the actual maximal Q value:

- sample environments:

- the detector: based on the Anger principle and consists of an array of 8 x 8 photomultipliers, a 60 cm x 60 cm 6Li glass scintillator and a light disperser glass, which spread the light produced by a neutron event to an array of 3 x 3 photomultipliers

Source ZEL, Forschungszentrum Jülich

- actual dead-time (20kHz for 10% dead-time):

(faster detection electronics with dead-time constant lower than 1 microsec - allowing for counting rates of 250kHz for 10% dead-time - planned to be installed in Summer 2009)

- variable size beam-stop with monitor in the middle for measuring the transmission simultaneously with the sample measurement

Source: ZAT, Forschungszentrum Jülich

- the high resolution detector: to be installed in Summer 2009

- example of 2D rawdata measured at KWS-2:

- example of 2D data corrected for the detector sensitivity:

- Software for data correction and calibration: DAN - for Linux; QtiKWS for Windows and Linux