Evidence for Z=6 `magic number' in neutron-rich carbon isotopes
Abstract
The nuclear shell structure, which originates in the nearly independent motion of nucleons in an average potential, provides an important guide for our understanding of nuclear structure and the underlying nuclear forces. Its most remarkable fingerprint is the existence of the so-called `magic numbers' of protons and neutrons associated with extra stability. Although the introduction of a phenomenological spin-orbit (SO) coupling force in 1949 helped explain the nuclear magic numbers, its origins are still open questions. Here, we present experimental evidence for the smallest SO-originated magic number (subshell closure) at the proton number 6 in 13-20C obtained from systematic analysis of point-proton distribution radii, electromagnetic transition rates and atomic masses of light nuclei. Performing ab initio calculations on 14,15C, we show that the observed proton distribution radii and subshell closure can be explained by the state-of-the-art nuclear theory with chiral nucleon-nucleon and three-nucleon forces, which are rooted in the quantum chromodynamics.
Keywords
Cite
@article{arxiv.1709.03355,
title = {Evidence for Z=6 `magic number' in neutron-rich carbon isotopes},
author = {D. T. Tran and H. J. Ong and G. Hagen and T. D. Morris and N. Aoi and T. Suzuki and Y. Kanada-En'yo and L. S. Geng and S. Terashima and I. Tanihata and T. T. Nguyen and Y. Ayyad and P. Y. Chan and M. Fukuda and H. Geissel and M. N. Harakeh and T. Hashimoto and T. H. Hoang and E. Ideguchi and A. Inoue and G. R. Jansen and R. Kanungo and T. Kawabata and L. H. Khiem and W. P. Lin and K. Matsuta and M. Mihara and S. Momota and D. Nagae and N. D. Nguyen and D. Nishimura and T. Otsuka and A. Ozawa and P. P. Ren and H. Sakaguchi and C. Scheidenberger and J. Tanaka and M. Takechi and R. Wada and T. Yamamoto},
journal= {arXiv preprint arXiv:1709.03355},
year = {2018}
}
Comments
7 pages, 5 figures