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The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector-response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer

The gamma decay from Coulomb excitation of 68Ni at 600 MeV/nucleon on a Au target was measured using the RISING setup at the fragment separator of GSI. The 68Ni beam was produced by a fragmentation reaction of 86Kr at 900 MeV/nucleon on a 9Be target and selected by the fragment separator. The gamma rays produced at the Au target were measured with HPGe detectors at forward angles and with BaF2 scintillators at backward angles. The measured spectra show a peak centered at approximately 11 MeV, whose intensity can be explained in terms of an enhanced strength of the dipole response function (pygmy resonance). Such pygmy structure has been predicted in this unstable neutron-rich nucleus by theory.

The 'Ni nucleus has been identified among the products of deep-inelastic reactions of Ni projectiles bombarding '3OTe and~o 'Pb targets. Three new states, including the high-lying 2+ (2033 keV) and the 0.86 ms 5 isomer, indicate a substantial subshell closure at neutron number N = 40. The level structure and the observed very slow E3 transition speed are discussed within the shell model. PACS numbers: 27.50.+e, 21.60.Cs, 23.20.Lv, 25.70.Lm In spherical nuclei the 1g9/2 orbital is distinctly separated in energy from all other single-particle levels. This gives rise to the well established magicity of the neutron and proton numbers N, Z = 50 and points towards a somewhat less pronounced closure at N, Z = 40. For protons the Z = 40 subshell closure is clearly demonstrated by the well known level structure of the 9OZr nucleus [1], for which the lowest excitation is the 1.76 MeV 0+ state, the first 2+ state appears at 2.19 MeV, and the lowest lying particle-hole (p,~2g9t2) excitation produces the longlived 5 isomeric state. The study of similar features in