An important discovery Wigner made during the project was the Wigner effect. This is a swelling of the graphite moderator caused by the displacement of atoms by neutron radiation. The Wigner effect was a serious problem for the reactors at the Hanford Site in the immediate post-war period, and resulted in production cutbacks and a reactor being shut down entirely. It was eventually discovered that it could be overcome by controlled heating and annealing.
An important discovery Wigner made du:ring the project was the Wigner effect. This is a swelling of the graphite moderator caused by the displacement of atoms by neutron radiation. The Wigner effect was a serious probl!em for the reactors at the Hanford Site in the immediate post-war period, and resulte:d in production cutbacks ?and a reactor being shut down entirely. It was eventually discovered that it could be overcome by controlled heating and annealing.