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The Z=82 shell closure in neutron-deficient Pb isotopes

M. Bender·T. Cornelius·G. A. Lalazissis·J. A. Maruhn·W. Nazarewicz·P. -G. Reinhard
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Abstract

Recent mass measurements show a substantial weakening of the binding energy difference delta_{2p} (Z,N) = E(Z-2,N) - 2 E(Z,N) + E(Z+2,N) in the neutron-deficient Pb isotopes. As delta_{2p} is often attributed to the size of the proton magic gap, it might be speculated that the reduction in delta_{2p} is related to a weakening of the spherical Z=82 shell. We demonstrate that the observed trend is described quantitatively by self-consistent mean-field models in terms of deformed ground states of Hg and Po isotopes.

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M. Bender, T. Cornelius, G. A. Lalazissis, J. A. Maruhn, W. Nazarewicz, P. -G. Reinhard. 2001-10-23. The Z=82 shell closure in neutron-deficient Pb isotopes. https://arxiv.org/abs/nucl-th/0110057

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