Cryostat for Irradiating at 4.2°K

A cryostat for irradiating at 4.2°K is described. In this device, it is possible to irradiate samples with no intervening foils, to measure at 4.2°K, to study annealing in situ to over 100°K, and to achieve recovery beyond 350°K. A sample holder utilizing the high thermal conductivity of copper and sapphire is discussed.