Measuring the size of a neutron wave packet

Quantum particles, such as electrons and neutrons, can produce interference patterns similar to those observed with light waves in the famous Young's two-slit experiment. Even though each particle must pass through only one slit, it must sense the presence of both slits in order for the interference pattern to be formed. Within the framework of quantum mechanics, this phenomenon is "explained' by representing each particle as a wave packet of a particular spatial extent. Several experiments have been carried out to measure the wave packet width for neutrons with results varying up to 80 microns. Our goal is to use the SESANS method on Larmor and a diffraction-grating sample to improve current measurements, utilizing the fact that SESANS is inherently less sensitive to conventional resolution effects.