V19 PONTO II
In the framework of two BMBF funded projects the new instrument PONTO II (Polarized Neutron Tomography) was installed and tested successfully at the Helmholtz Zentrum Berlin. PONTO II is an improvement of PONTO I. Neutron guide NL1A reflects neutrons in a wave length range of 3 Å to 4,5 Å from a graphite crystal C (002) with a mosaicity of 0.4° to an optical bank. The wavelength can easily be varied infinitively between the limit values (+ 0.005°). Premium optical components such as collimators and polarizers make it possible to set up PONTO II for polarized as well as for unpolarized neutrons with a space resolution of . 55µm (unpolarized) and 130µm (polarized), respectively. At this high resolution radiographs and tomographs can be taken of the magnetic fields of a sample and their influence on the surrounding with a field of view of 40mm x 40mm. The detector is a 2k x 2k Andor CCD camera, mounted to a rail system so that the detector can be moved up to 4 m from the monochromator. The neutron flux density ranges from 5 x 106 to 2 x 106 n/cm2.sec. Neutron radiographs and tomographs can easily be extended with the help of other components such as cryostats, external magnetic fields, ovens etc. The instrument is operated by the Beuth Hochschule für Technik.
V12 Bent-crystal Diffractometer (USANS)
The instrument V12a (ultra small angle scattering, USANS) at the Helmholtz Zentrum Berlin is a new design which improves the old V12 instrument in several ways.. V12a is an ultra small angle scattering experiment jointly operated by the Beuth Hochschule für Technik and the Helmholtz Zentrum Berlin. It covers a Q range of 5x10-4 nm-1
3 n/cm2. The detector, is a DENEX TN200 area detector, and it can measure the position dependent intensity distribution as well as the total beam rate.