Persistence of the $Z=28$ Shell Gap Around $^{78}\mathrm{Ni}$: First Spectroscopy of $^{79}\mathrm{Cu}$

L. Olivier (1) , S. Franchoo (1) , M. Niikura , Z. Vajta , D. Sohler , P. Doornenbal , A. Obertelli (2) , Y. Tsunoda , T. Otsuka , G. Authelet (2) , H. Baba , D. Calvet (2) , F. Château (2) , A. Corsi (2) , A. Delbart (2) , J.M. Gheller (2) , A. Gillibert (2) , T. Isobe , V. Lapoux (2) , M. Matsushita , S. Momiyama , T. Motobayashi , H. Otsu , C. Péron (2) , A. Peyaud (2) , E.C. Pollacco (2) , J.Y. Roussé (2) , H. Sakurai , C. Santamaria (2) , M. Sasano , Y. Shiga , S. Takeuchi , R. Taniuchi , T. Uesaka , H. Wang , K. Yoneda , F. Browne , L.X. Chung , Z. Dombradi , F. Flavigny (1) , F. Giacoppo , A. Gottardo (1) , K. Hadyńska-Klęk , Z. Korkulu , S. Koyama , Y. Kubota , J. Lee , M. Lettmann , C. Louchart , R. Lozeva (3) , K. Matsui , T. Miyazaki , S. Nishimura , K. Ogata , S. Ota , Z. Patel , E. Sahin , C. Shand , P.A. Söderström , I. Stefan (1) , D. Steppenbeck , T. Sumikama , D. Suzuki (1) , V. Werner , J. Wu , Z. Xu

1 IPNO - Institut de Physique Nucléaire d'Orsay
2 IRFU - Institut de Recherches sur les lois Fondamentales de l'Univers
3 IPHC - Institut Pluridisciplinaire Hubert Curien

In-beam γ-ray spectroscopy of Cu79 is performed at the Radioactive Isotope Beam Factory of RIKEN. The nucleus of interest is produced through proton knockout from a Zn80 beam at 270  MeV/nucleon. The level scheme up to 4.6 MeV is established for the first time and the results are compared to Monte Carlo shell-model calculations. We do not observe significant knockout feeding to the excited states below 2.2 MeV, which indicates that the Z=28 gap at N=50 remains large. The results show that the Cu79 nucleus can be described in terms of a valence proton outside a Ni78 core, implying the magic character of the latter.

Domaines: Physique Nucléaire Expérimentale [nucl-ex]

L. Olivier, S. Franchoo, M. Niikura, Z. Vajta, D. Sohler, et al.. Persistence of the $Z=28$ Shell Gap Around $^{78}\mathrm{Ni}$: First Spectroscopy of $^{79}\mathrm{Cu}$. Physical Review Letters, 2017, 119 (19), pp.192501. ⟨10.1103/PhysRevLett.119.192501⟩. ⟨hal-01645659⟩