Neutrons are wonderful travelers. They pass right through all sorts of materials, take all obstacles in stride and arrive on the other side with lots of stories to tell. Scientists just love them!
In neutron scattering, you send a beam of neutrons into a piece of known or unknown material and pick up the individual neutrons on the other side. From the paths they took through the material you can draw conclusions about the material’s structure, the geometrical arrangement of the atoms, while the speed of the neutrons on their way through the material tells you a lot about the atoms’ energy states, the directions of their spins, things like that.
Together, all this information helps you to map new terrain in new materials and to explore the mysteries of seemingly well-known stuff.
But catching the neutrons is the trick. Because you can never tell which path they will be taking. So to catch them you have to cast a very wide net. Which in the case of nearly light-speed neutrons means a detector chamber of submarine steel and with an outer-space vacuum, the size of a beached blue whale or two. In other words: a massive thing.
This is what NEAT will be. A time-of-flight spectrometer nested in a large vacuum chamber full of detectors, equipped with exchangeable neutron guides and a custom-made airlock system for speedy sample exchange. So, despite its bulk, it will be a pretty nimble instrument, flexible, fast and strong.
But first, the ‘bulky beast’ has to be installed. Which brings some challenges of its own…