An investigation of the effect of surface damage on the intensity of diffracted neutrons

The possible effect of surface damage on the intensity of diffracted neutrons has been investigated by a series of measurements for a plate-shaped crystal of SrF₂ with the large faces alternatively polished and roughened to various degrees. No significant effects were observed until the crystal thickness was reduced to about 1.7 mm and it is concluded that inhomogeneity of the extinction properties within the volume of the crystal is likely to be a far more important effect for normal neutron diffraction experiments.