Helium release from aged palladium tritide

Experimental studies of helium release from aged PdT{sub {ital x}} show that the helium-to-metal-atom ratio saturates at a value of (He)/(Pd){congruent}0.5 under conditions of ambient-temperature storage. Below this value, very little helium release occurs. Thermal desorption experiments show that release from a sample with (He)/(Pd){congruent}0.3 requires temperatures in excess of {similar to}600 K, while release from a sample with (He)/(Pd){congruent}0.02 requires temperatures in excess of at least 1300 K. These results are related to the question of the disposition of helium that would be produced by hypothetical fusion reactions in a PdD{sub {ital x}} electrode.