Deuterium heat pipes—cryogenic targets for COSY experiments

A new target version with a long gravity-assisted heat pipe section was constructed. The target material deuterium (D2) is used as a heat transport medium and high heat transfer is achieved by convection. This design drastically reduces the weight of the system to less than 10 g in the 32 cm long standard geometry, as compared with the previous copper heat conductors of 600 g. There are no massive metallic parts left close to the interaction area. The cycle time of cooling down to the operating temperature or heating up to room temperature is much shorter than that with the previous solid heat conductors. The characteristics at steady-state operating conditions of the heat pipe–target system were measured for deuterium as the working fluid.