-CRYogenic ProTon and Alpha target system-
CRYPTA provides compact liquid hydrogen, deuterium and helium targets for radioisotope beam experiments at RIKEN. A hydrogen, deuterium or helium gas is liquefied by a Gifford-McMahon cycle refrigerator, rather than being supplied as a cryogenic liquid. The liquefied gas is accumulated in a target cell placed at the center of a γ-ray detector array. The targets have been operated stably in several experiments.