A Precise Determination of the Half-Life and Average Energy of Tritium Decay

A precise determination of the half-life of tritium and of the average energy released by the decay has been carried out. The half-life was determined from measurements of the quantity of tritium contained in a sample and the rate at which that quantity gave rise to He³. The average energy release was determined from additional measurements on the same sample of the rate at which the sample liberated heat. The value found for the half-life was 12.46±{}0.1 years. That found for the average energy released by decay of neutral tritium to neutral helium was 5.69±{}0.04 kev.