Selective population of the [1s2s] {sup 1}S{sub 0} and [1s2s] {sup 3}S{sub 1} states of He-like uranium

• Published in: Physical review. A, Atomic, molecular, and optical physics Atomic, molecular, and optical physics, 2006-07, Vol.74 (1)
• Main Authors: Rzadkiewicz, J., The Soltan Institute for Nuclear Studies, 05-400 Swierk, Stoehlker, Th, Gumberidze, A., Reuschl, R., Spillmann, U., Tashenov, S., Trotsenko, S., Institut fuer Kernphysik, Universitaet Frankfurt, Banas, D., Beyer, H. F., Bosch, F., Brandau, C., Ionescu, D. C., Kozhuharov, C., Nandi, T., Dong, C. Z., Fritzsche, S., Surzhykov, A., Gojska, A., Hagmann, S., Sierpowski, D.
• Format: Article
• Language: English
• Subjects: ATOMIC AND MOLECULAR PHYSICS; CATIONS; CORRECTIONS; DECAY; DISTRIBUTION; EMISSION SPECTRA; IONIZATION; MOLECULE COLLISIONS; MOLECULES; PHOTON EMISSION; PROBABILITY; RELATIVISTIC RANGE; S STATES; URANIUM; URANIUM IONS; X RADIATION; X-RAY SPECTRA
• ISSN: 1050-2947; 1094-1622
• DOI: 10.1103/PHYSREVA.74.012511

The formation of the [1s2s] S states in heliumlike uranium (U{sup 90+}) has been studied in relativistic collisions of initially lithiumlike uranium (U{sup 89+}) ions with N{sub 2} target molecules. By measuring projectile x-ray emission in coincidence with projectile ionization, a strong selectivity for the formation of the [1s2s] S states in heliumlike uranium is observed. This selectivity is found to be unaffected by the subsequent rearrangement of the atomic orbitals involved. By measuring the photon emission associated with the decay of the [1s2s] {sup 1}S{sub 0} and the [1s2s] {sup 3}S{sub 1} substates, we obtain for their relative population probabilities a ratio of close to 1. This finding deviates considerably from the assumption of a statistical distribution 2J+1.