The effects of multiple scattering on the analysis of USANS data

Abstract

Small-angle neutron scattering (SANS) and ultra-small-angle neutron scattering (USANS) are widely used to investigate the micro- and nano-structure of condensed matter. However, measurements on materials such as cements, clays etc. are often affected by multiple scattering. If a substantial number of neutrons experience more than one scattering event within a sample, the result is broadening of the angular distribution profile. Often samples cannot be made thin enough to guarantee single scattering and even in cases where it is possible to make thin samples, surface effects can sometimes lead to results that are not representative of the bulk material. In addition, for many SANS and USANS measurements there is no reliable method for determining whether or not a sample is thin enough to produce predominantly single scattering. Here we present a new method for extracting singly-scattered data from data affected by multiple scattering. One of the main advantages over our previously published method [1] is that this method is much easier to apply as it requires no initial modeling and fitting of the data.