Evidence for a new nuclear ‘magic number’ from the level structure of 54Ca

  title={Evidence for a new nuclear ‘magic number’ from the level structure of 54Ca},
  author={David Steppenbeck and Satoshi Takeuchi and Nori Aoi and Pieter Doornenbal and Michio M. Matsushita and H. W. Wang and H Baba and N. Fukuda and Shintaro Go and Michio Honma and Jinho Lee and Keishi Matsui and S. Michimasa and Tohru Motobayashi and Daiki Nishimura and Takaharu Otsuka and H. Sakurai and Yoshiaki Shiga and P.-A. S{\"o}derstr{\"o}m and T. Sumikama and H. Suzuki and R. Taniuchi and Yutaka Utsuno and J. J. Valiente-Dob{\'o}n and Ken-ichiro Yoneda},
Atomic nuclei are finite quantum systems composed of two distinct types of fermion—protons and neutrons. In a manner similar to that of electrons orbiting in an atom, protons and neutrons in a nucleus form shell structures. In the case of stable, naturally occurring nuclei, large energy gaps exist between shells that fill completely when the proton or neutron number is equal to 2, 8, 20, 28, 50, 82 or 126 (ref. 1). Away from stability, however, these so-called ‘magic numbers’ are known to… Expand
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