SESAME (Spin Echo Scattering Angle Measurement)

The newest LENS beamline, dubbed SESAME (Spin Echo Scattering Angle Measurement), measured its first neutrons on April 21, 2009. Started in the summer of 2006, this beamline has been the vision of IU professor Roger Pynn at CEEM. SESAME will use polarized neutrons to probe in-plane correlations on solid and liquid samples. The process relies upon precise magnetic fields to encode the scattering angle of neutrons into the final polarization of the beam. A 3He analyzer that is currently being designed and built by Dr. Mike Snow, also of CEEM, will be used as a polarizer filter for SESAME.

Several experiments at national labs over the past three years have provided proof-of-principle results for SESAME. The most recent experiments were performed at the NIST Center for Neutron Research and the Los Alamos Neutron Science Center, in which neutron reflectivity was carried out on a nanopatterned silicon stamp. The results have been confirmed through theoretical calculations, and provide a basis for analysis of future experiments on more complicated structures, such as biomembranes and block copolymers.

SESAME is a neutron scattering technique for probing nanometer-to micron-scale correlations of planer structure of a material. Pictured above is a cartoon of neutrons scattering off a biological membrane. SESAME will provide scientists with a method to ensure a high degree of in-plane uniformity in nanoscale materials.