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arXiv · 1010.2103

Early onset of ground-state deformation in the neutron-deficient polonium isotopes

T. E. Cocolios·W. Dexters·M. D. Seliverstov·A. N. Andreyev·S. Antalic·A. E. Barzakh·B. Bastin·J. Buscher·I. G. Darby·D. V. Fedorov·V. N. Fedosseyev·K. T. Flanagan·S. Franchoo·S. Fritzsche·G. Huber·M. Huyse·M. Keupers·U. Koster·Yu. Kudryavtsev·E. Mane·B. A. Marsh·P. L. Molkanov·R. D. Page·A. M. Sjoedin·I. Stefan·J. Van de Walle·P. Van Duppen·M. Venhart·S. G. Zemlyanoy·M. Bender·P. -H. Heenen
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Abstract

In-source resonant ionization laser spectroscopy of the even-$A$ polonium isotopes $^{192-210,216,218}$Po has been performed using the $6p^37s$ $^5S_2$ to $6p^37p$ $^5P_2$ ($λ=843.38$ nm) transition in the polonium atom (Po-I) at the CERN ISOLDE facility. The comparison of the measured isotope shifts in $^{200-210}$Po with a previous data set allows to test for the first time recent large-scale atomic calculations that are essential to extract the changes in the mean-square charge radius of the atomic nucleus. When going to lighter masses, a surprisingly large and early departure from sphericity is observed, which is only partly reproduced by Beyond Mean Field calculations.

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T. E. Cocolios, W. Dexters, M. D. Seliverstov, A. N. Andreyev, S. Antalic, A. E. Barzakh, B. Bastin, J. Buscher, I. G. Darby, D. V. Fedorov, V. N. Fedosseyev, K. T. Flanagan, S. Franchoo, S. Fritzsche, G. Huber, M. Huyse, M. Keupers, U. Koster, Yu. Kudryavtsev, E. Mane, B. A. Marsh, P. L. Molkanov, R. D. Page, A. M. Sjoedin, I. Stefan, J. Van de Walle, P. Van Duppen, M. Venhart, S. G. Zemlyanoy, M. Bender, P. -H. Heenen. 2010-10-11. Early onset of ground-state deformation in the neutron-deficient polonium isotopes. https://doi.org/10.1103/physrevlett.106.052503

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