Single-Slit Diffraction of Neutrons

Abstract

Observations are reported on single-slit diffraction of monochromatic slow neutrons (wavelength 4.43 \AA{}) upon passage through fine slits of width between 21 and 4.1 \ensuremath{\mu}. Gadolinium-edged slits were used because of the high-absorption cross section for this material, and the angular broadening effects in the range up to 20\ensuremath{''} of arc were studied on a high-resolution double-crystal spectrometer utilizing perfect crystals of silicon. The observed broadening agrees well with that calculated, and this supplies evidence on the width of the coherent wavefront of a neutron wave packet.