26-30 June 2011
Centro Culturale Altinate, Padova, Italy
Europe/Rome timezone

Coulomb Excitation of Isomeric states of <sup>70</sup>Cu

28 Jun 2011, 09:55
20m
Sala Polivalente (Centro Culturale Altinate, Padova, Italy)

Sala Polivalente

Centro Culturale Altinate, Padova, Italy

Via Altinate 71 Padova Italy

Speaker

Elisa Rapisarda (IKS Katholieke Universiteit Leuven)

Description

Extensive studies on Cu neutron-rich isotopes have been performed in recent years at REX-ISOLDE in the aim to investigate the nuclear structure in the vicinity of the N=40 sub-shell closure. In particular the study of odd-odd 68,70Cu nuclei was reported in [1] where for the first time low-energy Coulomb excitation measurements with isomeric radioactive post-accelerated beams were performed. For the case of 70Cu, a Iπ = 6- isomeric beam was used to study the multiplet of states (3-, 4-, 5-, 6-) arising from the π2p3/2⊗μ1g9/2 configuration. The isomeric nature of the 6- and 3- states was experimentally determined in previous work [2]. The beam was produced at ISOLDE, CERN by selective laser ionization technique and then post-accelerated by REX-ISOLDE to about 2.8 MeV/ nucleon. Gamma rays were detected with the MINIBALL high resolution Ge detector array. The 4- state of the multiplet was populated by Coulomb excitation and the reduced transition probability B(E2, 6-→4-) value was determined. The remaining member of the multiplet, the 5- state, was not observed in this experiment . To provide complementary information about the energy levels and reduced transition probabilities of the connecting transitions within the states of the multiplet, a new experiment was performed using a Iπ = 3- isomeric beam. Besides the known transition deexciting the 4- state [1], gamma rays of 511 keV were observed for the first time and were unambiguously associated to the 5- state deexcitation. This observation fixes the energy, spin and parity of this state, completing the low-energy level scheme of 70Cu. Moreover B(E2) values for all the possible E2 transitions within the multiplet are now precisely measured and will be compared with extensive shell-model calculations to get additional information on the underlying structure of the π2p3/2⊗μ1g9/2 multiplet. [1] I. Stefanescu et al. PRL98, 122701 (2007) [2] J. Van Roosbroek et al. PRC69, 034313 (2004)

Primary author

Elisa Rapisarda (IKS Katholieke Universiteit Leuven)

Presentation Materials