Small Energy Transfer Scattering of Cold Neutrons from Liquid Argon

The quasielastic scattering of 4.1-{} neutrons from liquid argon at 94±{}2^∘{}K has been studied for wave-vector transfers in the region 1.3 ^-1<Q<2.6 ^-1 which covers the main peak in the liquid structure factor. The peak intensity and peak width exhibit the same type of oscillatory behavior as observed earlier in other coherently scattering liquids. A simple modification of Vineyard's convolution approximation is described by which these oscillations are quantitatively explained.