YS-SANS – Small Angle Neutron Scattering Instrument Yellow Submarine
Instrument responsible: László Almásy, Adél Len, Renáta Ünnep
The SANS diffractometer Yellow Submarine covers a Q-range from 0.003 to 0.7 Å-1 allowing to probe structures at length scales from 5 Å to 1500 Å. It has a wide range of applications from studies of defects and precipitates in materials, surfactant and colloid solutions, ferromagnetics, magnetic correlations, alloy segregation, polymers, proteins, biological membranes. The instrument is installed on the curved neutron guide No.2, with 4x4 cm2 cross-section, made of (1.5 ϴc) supermirrors. The beam is monochromatized by a multidisc type velocity selector, (L. Rosta: Physica B 174 (1991) 562) the rotation speed can be tuned between 700 and 7000 rot/min (wavelengths between 3 and 12 Å). The width Δλ/λ of the transmitted wavelength distribution can be varied between 12% and 30% by changing the tilt angle between the selector axis and the direction of the neutron beam. The collimation distance is 5 m.
SANS schedule: http://www.kfki.hu/~sans/schedule.htm
In most of the experiments an automatic sample changer with 6 positions is used. It can be thermostated from an external bath between 10°C and 90°C. An 11 position sample changer can be used for ambient temperature experiments. Liquid nitrogen cryostat, or closed cycle refrigerator can be used (from 10K-300K). Electromagnets can also be mounted on the sample table (field 1.6T in the gap 25mm), with a vertical automatic sample holder with 9 sample positions.
The scattered neutrons are detected by a 64 x 64 pixels (1cm x 1cm pixel size) two dimensional position sensitive LETI (Grenoble, France) detector filled with BF3 gas.
The control and data acquisition electronics has been made by Laboratoire Léon Brillouin, Saclay, France, and ANTE Ltd., Budapest, Hungary, the data acquisition software was designed in our Lab.
|Beam tube:||Cold neutron guide No. 2/1|
|Monochromator:||Multidisk velocity selector|
|Detector:||2D position sensitive, 64x64 cm2, filled with BF3 gas|
|Flux at the guide exit:||5 x 107 n/cm2/sec|
|Sample-to-detector distance:||Continuously adjustable between 1 m and 5.5 m|
|Incident wavelength:||3 - 12 Å|
|Wavelength spread:||Adjustable between 12 - 30 %|
Scheme of the SANS diffractometer Yellow Submarine
Figure 1. Scheme of the SANS diffractometer Yellow Submarine