Applied Ultracold Neutrons: Surface Contamination Profiles

Ultracold neutrons (UCN) are free neutrons of energies less than 300 neV, routinely trapped and manipulated for fundamental particle physics measurements. Their primary characteristic – total internal reflection off of materials of high enough Fermi Potential relative to their energy – causes them to thoroughly explore the surfaces within their space, lending them utility as a surface probe. This surface probe capability is being developed to map the corrosion of actinides – hydrogen content that upscatters the UCN probe. A novel technique involving kinematic imaging of these upscattered UCN from a sample surface is being developed. The upscattered UCN position is projected onto a lithium-6 doped scintillator film and the light output read into a PIMAX CCD camera for reconstruction. This allows us to reconstruct the surface of the hydrided actinide.