Elsevier, Physica B: Condensed Matter, (276-278), p. 52-54
DOI: 10.1016/s0921-4526(99)01323-x
Full text: Unavailable
Presently high-resolution instruments for small-angle neutron scattering use the conventional pinhole collimation. For high resolution these instruments have to be extremely long (80 m for D11). Much shorter instruments with high resolution and better intensity can be built with focusing mirrors. The high-quality mirrors, which were developed for the X-ray telescope ROSAT, served as prototypes for our neutron imaging mirrors. Recently we succeeded in building a 20 m long focusing instrument at the ILL in Grenoble. The image has a very low parasitic halo. Aberrations are mainly due to gravity. Test experiments on polymeric precipitates down to Q=4×10−4 Å−1 were successfully carried out. In Jülich we now are building a focusing SANS-instrument and reflectometer with major geometrical improvements of the mirror design. For the SANS-instrument, a Q-range down to Q≈10−4 Å−1 is expected. For the reflectometer, a perpendicular Q⊥-range between 10−2 Å−1<Q⊥<10−1 Å−1 is envisaged, with a ΔQ⊥ resolution of about ΔQ⊥≈10−2 Å−1.