Coulomb excitation of the 3 isomer in 70Cu

Post-accelerated isomerically purified radioactive beams, available at the CERN On-Line Isotope Mass Separator facility using the resonant ionization laser technique, have been used to study the Coulomb excitation of the 𝐼𝜋 = 3− state in 70Cu (𝑍=29, 𝑁=41). While first results using a 𝐼𝜋=6− beam were reported previously, the present complementary experiment allows us to complete the study of the multiplet of states (3−, 4−, 5−, 6−) arising from the 𝜋⁢2⁢𝑝3/2⁢𝜈⁢1⁢𝑔9/2 configuration. Besides the known 𝛾-ray transition deexciting the 4− state, a ground-state 𝛾 ray of 511(3) keV was observed for the first time and was unambiguously associated with the 5− state deexcitation. This observation fixes the energy, spin, and parity of this state, completing the low-energy level scheme of 70Cu. 𝐵⁡(𝐸⁢2) values for all possible 𝐸⁢2 transitions within the multiplet were determined. A comparison with large-scale shell model calculations using different interactions and valence spaces shows the importance of proton excitation across the 𝑍=28 shell gap and the role of the 2⁢𝑑5/2 neutron orbital.

Authors: E. Rapisarda, I. Stefanescu, D. L. Balabanski, B. Bastin, A. Blazhev, N. Bree, M. Danchev, B. Bruyneel T. Davinson, P. Delahaye, J. Diriken, J. Eberth, G. Georgiev, D. Fedorov, V. N. Fedosseev, E. Fiori, S. Franchoo, Ch. Fransen, K. Geibel, K. Gladnishki, K. Hadyńska, H. Hess, K. Heyde, M. Huyse, O. Ivanov, J. Iwanicki, J. Jolie, M. Kalkuehler, Th. Kröll, R. Krücken, U. Köster, G. Lo Bianco, R. Lozeva, B. A. Marsh, S. Nardelli, F. Nowacki, N. Patronis, P. Reiter, M. Seidlitz, K. Sieja, N. Smirnova, J. Srebrny, J. Van de Walle, P. Van Duppen, N. Warr, F. Wenander, K. Wimmer, K. Wrzosek, S. Zemlyanoi and M. Zielińska

Doi: 10.1103/PhysRevC.84.064323

Issue number:

Journal: Phys. Rev. C

Page number: 064323

Published on: 2011-12-27

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