The excited states of the odd nucleus La140 populated by the beta decay of Ba140

摘要: Abstract Coincidence measurements between γ-rays and conversion electrons β-rays verify the existence of 43 keV 580 levels in odd nucleus La140. By delayed coincidence techniques mean lifetime level has been determined as τ=(7.5±2) × 10−10 sec upper limits for 466, 162 29.6 were found to be τ ≦ 1.1 10−11 sec, 1.5 6 respectively. The γ-γ angular correlation 304-162 cascade yielded result: W (θ)=1+(0.055±0.01)P2(cos θ)−(0.009±0.015)P4(cos θ). 29.6, 13.3, 132 transitions have M1 multipolarities with very low E2 admixture. present results are consistent spin assignments 3−, 2−, 1−, 1− (0−) ground state, 43, 162, 466 levels, Comparison made observed transition probabilities those derived from shell model calculations terms coupling neutron proton.