A "factor method" of evaluating the double-scattering correction for inelastic-neutron-scattering experiments with an infinite-plane-slab specimen has been developed. Using appropriate dynamical models, calculations have been made both for highly compressed room-temperature gaseous methane and for liquid methane at 98 °K. As a result, the agreement between analytical results with measurements is remarkably improved. In addition, the model sensitivity of the correction and the advantages of reflection-type experimental geometry over transmission-type are investigated.

• Received 7 May 1971

DOI:https://doi.org/10.1103/PhysRevA.4.1560