Atomic effects accompanying the beta decay of tritium

The results of the first experiment designed to measure the difference between the beta-decay constants of atomic and molecular tritium Δλ=λ_a–λ_m are presented. The experimental scheme calls for the creation of two identical samples of a gas mixture containing helium-4 and molecular tritium followed by the treatment of one of them for the purpose of bringing the tritium into the atomic state. The value of Δλ is determined by comparing the growth rates of the ratio of the concentration of radiogenic helium-3 to the concentration of helium-4 in the samples with molecular and atomic tritium. The value Δλ=(4.6±0.8)×10⁻¹² s⁻¹, which corresponds o a relative change in the decay constant amounting to ∼0.26%, is obtained. Zh. Tekh. Fiz. 69, 19–21 (September 1999)