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arXiv · 1310.2344

Extinction of the N=20 neutron-shell closure for 32Mg examined by direct mass measurements

A. Chaudhuri·C. Andreoiu·T. Brunner·U. Chowdhury·S. Ettenauer·A. T. Gallant·G. Gwinner·A. A. Kwiatkowski·A. Lennarz·D. Lunney·T. D. Macdonald·B. E. Schultz·M. C. Simon·V. V. Simon·J. Dilling
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Abstract

The 'island of inversion' around $^{32}$Mg is one of the most important paradigm for studying the disappearance of the stabilizing 'magic' of a shell closure. We present the first Penning-trap mass measurements of the exotic nuclides $^{29-31}$Na and $^{30-34}$Mg, which allow a precise determination of the empirical shell gap for $^{32}$Mg. The new value of 1.10(3) MeV is the lowest observed shell gap for any nuclide with a canonical magic number.

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A. Chaudhuri, C. Andreoiu, T. Brunner, U. Chowdhury, S. Ettenauer, A. T. Gallant, G. Gwinner, A. A. Kwiatkowski, A. Lennarz, D. Lunney, T. D. Macdonald, B. E. Schultz, M. C. Simon, V. V. Simon, J. Dilling. 2013-10-09. Extinction of the N=20 neutron-shell closure for 32Mg examined by direct mass measurements. https://doi.org/10.1103/physrevc.88.054317

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