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arXiv · 1202.4873

Nuclear Charge Radius of $^{12}$Be

Andreas Krieger·Klaus Blaum·Mark L. Bissell·Nadja Frömmgen·Christopher Geppert·Michael Hammen·Kim Kreim·Magdalena Kowalska·Jörg Krämer·Thomas Neff·Rainer Neugart·Gerda Neyens·Wilfried Nörtershäuser·Christian Novotny·Rodolfo Sanchez·Deyan T. Yordanov
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Abstract

The nuclear charge radius of $^{12}$Be was precisely determined using the technique of collinear laser spectroscopy on the $2s_{1/2}\rightarrow 2p_{1/2, 3/2}$ transition in the Be$^{+}$ ion. The mean square charge radius increases from $^{10}$Be to $^{12}$Be by $\delta ^{10,12} = 0.69(5) \fm^{2}$ compared to $\delta ^{10,11} = 0.49(5) \fm^{2}$ for the one-neutron halo isotope $^{11}$Be. Calculations in the fermionic molecular dynamics approach show a strong sensitivity of the charge radius to the structure of $^{12}$Be. The experimental charge radius is consistent with a breakdown of the N=8 shell closure.

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Andreas Krieger, Klaus Blaum, Mark L. Bissell, Nadja Frömmgen, Christopher Geppert, Michael Hammen, Kim Kreim, Magdalena Kowalska, Jörg Krämer, Thomas Neff, Rainer Neugart, Gerda Neyens, Wilfried Nörtershäuser, Christian Novotny, Rodolfo Sanchez, Deyan T. Yordanov. 2012-02-22. Nuclear Charge Radius of $^{12}$Be. https://doi.org/10.1103/physrevlett.108.142501

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