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arXiv · 2005.03713

Detection of missing low-lying atomic states in actinium

Ke Zhang·Dominik Studer·Felix Weber·Vadim M. Gadelshin·Nina Kneip·Sebastian Raeder·Dmitry Budker·Klaus Wendt·Tom Kieck·Sergey G. Porsev·Charles Cheung·Marianna S. Safronova·Mikhail G. Kozlov
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Abstract

Two lowest-energy odd-parity atomic levels of actinium, 7s^27p 2P^o_1/2, 7s^27p 2P^o_3/2, were observed via two-step resonant laser-ionization spectroscopy and their respective energies were measured to be 7477.36(4) cm^-1 and 12 276.59(2) cm^-1. The lifetimes of these states were determined as 668(11) ns and 255(7) ns, respectively. In addition, these properties were calculated using a hybrid approach that combines configuration interaction and coupled-cluster methods in good agreement. The data are of relevance for understanding the complex atomic spectra of actinides and for developing efficient laser-cooling and ionization schemes for actinium, with possible applications for high-purity medicalisotope production and future fundamental physics experiments with this atom.

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Ke Zhang, Dominik Studer, Felix Weber, Vadim M. Gadelshin, Nina Kneip, Sebastian Raeder, Dmitry Budker, Klaus Wendt, Tom Kieck, Sergey G. Porsev, Charles Cheung, Marianna S. Safronova, Mikhail G. Kozlov. 2020-05-07. Detection of missing low-lying atomic states in actinium. https://doi.org/10.1103/physrevlett.125.073001

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