Focusing Monochromators for Neutron Diffraction

Recent advances in bent crystal monochromators for neutron powder diffraction are reviewed. As monochromators for high resolution instruments, bent perfect crystals may be superior to flat mosaic crystals. They can provide both real-space focusing on sample and scattering-space focusing in diffraction for a wide range of detector angles. Double crystal monochromators with anti-parallel (+,+) settings can condense large area neutron beams into millimeter-size spots. Their focusing range for diffraction is narrow, but the situation is of interest for microfocus stress profiling measurements. The design of single and double monochromators for stress measurements by neutron diffraction is discussed. To take full advantage of focusing, techniques for plastic bending of crystals will have to be developed.

Hali tarjima qilinmagan