Dresden 2006 – wissenschaftliches Programm
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VA: Vakuumphysik und Vakuumtechnik
VA 4: Instruments for neutrons
VA 4.6: Vortrag
Montag, 27. März 2006, 16:20–16:40, HSZ 101
The new V12a diffractometer at HMI and neutron computerized tomography — •Markus Strobl1,2, Wolfgang Treimer1,2, and André Hilger1,2 — 1Hahn Meitner Institut, Glienickerstr. 100 14109 Berlin — 2University of Applied Sciences (TFH) Luxemburger Str. 10 13353 Berlin
Double crystal diffractometers (DCD) are widely used for structural investigations at the limit between macroscopic and microscopic inner structures of sample materials. Operating in an ultra small angle neutron scattering (USANS) q-range between 10^(-4) nm^(-1) and 10^(-1) nm^(-1) structures between 50 nm and nearly 100 micrometer can be resolved. Hence the DCD connects the resolvable ranges of small angle neutron scattering (SANS) instruments and neutron tomography facilities. However, the DCD does not only link the resolvable size ranges but can also be operated to yield both, q-space information on microscopic structures combined with real space information in the range of macroscopic inner structures. This method was developed in recent years at the V12 DCD at HMI by introducing refraction and USANS contrast for tomography. The new V12 DCD set-up has now been optimised to exploit all the opportunities of USANS measurements, refraction and USANS contrast tomography and conventional attenuation contrast tomography with an intense monochromatic neutron beam. The new contrast methods will be introduced as well as the final set-up of the V12 instrument. Additionally several examples and results achieved by the new techniques and instrument will be given.