At the radioactive ion beam facility REX-ISOLDE, neutron-rich zinc isotopes were investigated using lowenergy Coulomb excitation. These experiments have resulted in B(E2, 2 74,76 Zn and the determination of the energy of the first excited 2 + 1 states in 78,80 Zn. The zinc isotopes were produced by high-energy proton-(A = 74, 76, 80) and neutron-(A = 78) induced fission of 238 U, combined with selective laser ionization and mass separation. The isobaric beam was postaccelerated by the REX linear accelerator and Coulomb excitation was induced on a thin secondary target, which was surrounded by the MINIBALL germanium detector array. In this work, it is shown how the selective laser ionization can be used to deal with the considerable isobaric beam contamination and how a reliable normalization of the experiment can be achieved. The results for zinc isotopes and the N = 50 isotones are compared to collective model predictions and state-of-the-art large-scale shell-model calculations, including a recent empirical residual interaction constructed to describe the present experimental data up to 2004 in this region of the nuclear chart.

Abstract. The Miniball germanium detector array has been operational at the REX (Radioactive ion beam EXperiment) post accelerator at the Isotope Separator On-Line facility ISOLDE at CERN since 2001. During the last decade, a series of successful Coulomb excitation and transfer reaction studies have been performed with this array, utilizing the unique and high-quality radioactive ion beams which are available at ISOLDE. In this article, an overview is given of the technical details of the full Miniball setup, including a description of the γ-ray and particle detectors, beam monitoring devices and methods to deal with beam contamination. The specific timing properties of the REX-ISOLDE facility are highlighted to indicate the sensitivity that can be achieved with the full Miniball setup. The article is finalized with a summary of some physics highlights at REX-ISOLDE and the utilization of the Miniball germanium detectors at other facilities.

The 9 Li + 2 H reaction has been investigated at 2.36 MeV/u at the REX-ISOLDE facility. In this Letter we focus on the 10 Li + p channel which potentially holds spectroscopic information on the unbound nucleus 10 Li. The experimental excitation energy spectrum and angular distribution are compared with CCBA calculations. These calculations clearly support the existence of a low-lying (s) virtual state, with a (negative) scattering length of the order a s ∼ 13-24 fm and a p 1/2 resonance with an energy of E r 0.38 MeV and a width of Γ 0.2 MeV.

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