Institut für Kernchemie, Johannes Gutenberg-Universität Mainz, D-55128 Mainz, Germany.
Phys Rev Lett. 2012 Apr 6;108(14):142501. doi: 10.1103/PhysRevLett.108.142501. Epub 2012 Apr 3.
The nuclear charge radius of (12)Be was precisely determined using the technique of collinear laser spectroscopy on the 2s(1/2)→2p(1/2,3/2) transition in the Be(+) ion. The mean square charge radius increases from (10)Be to (12)Be by δ<r(c)(2)>(10,12)=0.69(5) fm(2) compared to δ<r(c)(2)>(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.
利用贝离子 2s(1/2)→2p(1/2,3/2)跃迁的共线激光光谱技术，精确测定了 (12)Be 的核电荷半径。与单中子晕同位素 ^{11}Be 的 δ<r(c)(2)>(10,11)=0.49(5) fm(2) 相比，(10)Be 到 (12)Be 的平均平方电荷半径增加了 δ<r(c)(2)>(10,12)=0.69(5) fm(2)。在费米分子动力学方法的计算中，电荷半径对 ^{12}Be 的结构表现出很强的敏感性。实验电荷半径与 N=8 壳层闭合的破裂一致。
