Photography of Neutron Diffraction Patterns

Photography of slow neutron radiation can be accomplished through use of fluorescent screens in which secondary radiation (beta particles, gamma rays, or visible light) is used to produce photographic action. Thus, as part of a comprehensive study on screen-film combinations, a study is made of the sensitivity and spatial resolution of Li/sup 6/ metal-zinc sulfide systems and Li/ sup 6/F-- ZnS systems in v-arious forms of combination. Hence, the relative neutron exposures required for the different screens to produce a photographic density of 0.5 on Tri-X film with monochromatic neutrons of wavelength 1.5 A are tabulated. It is seen that the homogeneously-mixed screen is more sensitive by an order of magnitude than the heterogeneous screens. Results are also given which show the screen response as a function of mixing ratio (ZnS to Li/sup 6/F) for different neutron wavelengths and an optimum weight ratio of about 4 is suggested. (N.W.R.)