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arXiv · 0909.5618

A new derivation of symmetry energy from nuclei beyond the β-stability line

V. M. Kolomietz·A. I. Sanzhur
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Abstract

We suggest the procedure of direct derivation of the symmetry energy from the shift of neutron-proton chemical potentials Δλ=λ_{n}- λ_{p} for nuclei beyond the beta-stability line. We observe the presence of anomalous strong (about 15%) shell oscillations at the symmetry energy coefficient b_{sym}. Our results do not confirm the existence of exceptionally large values of the symmetry energy coefficient at mass number A\approx 100 which was earlier reported in Ref.[2]. Using the fitting procedure, we have evaluated the volume, b_{sym,vol}, and surface, b_{sym,surf}, contributions to the symmetry energy. We have estimated the experimental value of surface-to-volume ratio as r_{S/V}=|b_{sym,surf}}|/b_{sym,vol}\approx 1.7 for the fitting interval A\geq 50.

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V. M. Kolomietz, A. I. Sanzhur. 2009-12-22. A new derivation of symmetry energy from nuclei beyond the β-stability line. https://doi.org/10.1103/physrevc.81.024324

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