The set up for the polarized measurements is shown in the scheme above. The spectrum measurements with flipper on and off show that the beam is highly polarized. The flipping ratio has a maximum between 2 and 3 Angstrom. The beam polarization averaged over the whole spectrum has been determined to be 96.6 %
Experiment I: polarized proton spin filter
The spin dependence of the neutron proton nuclear interaction can be exploited to build a spin filter operating efficiently over the whole energy range of neutrons from meV to keV. In a test of principle experiment a polarized proton target based on a novel dynamic nuclear polarization (DNP) process has been used to spin filter the white beam at BOA. The system operates at only 0.3 T and 100 K.
Experiment II: adaptive neutron optics
With a prototype adaptive neutron-optical device it was possible to achieve a tiny focal spot on small samples. By adapting the applied force, the y-position of the device and the angle of incidence, the neutrons could be focused in one dimension on a spot size of below 1mm yielding an intensity gain factor of 7.8.