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arXiv · 1201.1097

Evolution of the N=50 gap from Z=30 to Z=38 and extrapolation towards 78Ni

M. -G. Porquet·O. Sorlin
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Abstract

The evolution of the N=50 gap is analyzed as a function of the occupation of the proton f5/2 and p3/2 orbits. It is based on experimental atomic masses, using three different methods of one or two-neutron separation energies of ground or isomeric states. We show that the effect of correlations, which is maximized at Z=32 could be misleading with respect to the determination of the size of the shell gap, especially when using the method with two-neutron separation energies. From the methods that are the least perturbed by correlations, we estimate the N=50 spherical shell gap in 78Ni. Whether 78Ni would be a rigid spherical or deformed nucleus is discussed in comparison with other nuclei in which similar nucleon-nucleon forces are at play.

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M. -G. Porquet, O. Sorlin. 2012-01-05. Evolution of the N=50 gap from Z=30 to Z=38 and extrapolation towards 78Ni. https://doi.org/10.1103/physrevc.85.014307

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