A liquid hydrogen-deuterium target

The design of a liquid hydrogen-deuterium target is described in which the gas is liquefied at the expense of boiling off liquid He-vapour. A closed gas circulation system is used in the target; this increases the safety of operation and makes it easy to replace H₂ by D₂. The target design allows the use of detachable heads appropriate to the requirements of a specific experiment. The working time obtainable from one filling of helium is 80h for a liquid hydrogen target, (LHT) and 60 h for a liquid deuterium target (LDT). 2.85 I of liquid He are required to liquefy 1 I of H₂ and 3.8 l for 1 of D₂