For more than forty years nuclear physicists have proposed experiments at various facilities to measure the strength of attraction between two neutrons. This strength of attraction would be measured by directly colliding neutrons and yet no successful measurements have been done. The two primary obstacles have been a not having an intense enough source of neutrons and not having a sufficiently detailed knowledge of the neutron source characteristics and other experimental parameters.
With support from the NSF, an international collaboration is constructing an experimental apparatus at the All Technical Institute in Snezhinsk, Russia to perform the first ever direct neutron-neutron scattering experiment. The YAGUAR reactor in Snezhinsk has the requisite neutron intensity, and computer modeling of the experimental apparatus has helped with the design of the apparatus and will allow us to extract the quantities of interest from the data. Gettysburg College has a history of incorporating student participation in physics research, and is teaching undergraduates some of the computational techniques necessary for this hallmark experiment.