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Gamma-ray spectroscopy is intensively used at GANIL to measure low lying states in exotic nuclei on the neutron-rich as well as on the neutron-deficient side of the nuclear chart. On the neutron deficient border, gamma-rays have been observed for the first time in 92Pd. The level scheme which could be established points to the role of isoscalar pairing. On the neutron rich side, the lifetime of excited states in nuclei around 68Ni have been been measured using the plunger technique. This allows us to study the evolution of collectivity in a broad range of nuclei. In 2014 GANIL will host the AGATA array for a campaign of at least 2 years. This array is based on the gamma-ray tracking technique, which allows an impressive gain in resolving power. [ABSTRACT FROM AUTHOR]

High spin states in Bismuth and Thallium nuclei near the Z = 82 shell closure and Cesium nuclei near the N = 82 shell closure in A = 190 and A = 130 regions, respectively, have been experimentally investigated using heavy-ion fusion evaporation reaction and by detecting the gamma rays using the Indian National Gamma Array (INGA). Interesting shape properties in these transitional nuclei have been observed. The results were compared with the neighboring nuclei in these two regions. The total Routhian surface (TRS) calculations have been performed for a better understanding of the observed properties. In mass region A = 190, a change in shape from spherical to deformed has been observd around neutron number N = 112 for the Bi (Z = 83) isotopes with proton number above the magic gap Z = 82, whereas, the shape of Tl (Z = 81) isotopes with proton number below the magic gap Z = 82 remains stable as a function of neutron number. An important transition from aplanar to planar configuration of angular momentum vectors leading to the occurance of nuclar chirality and magnetic rotation, respectively, has been proposed for the unique parity πh11/2 ⊗ vh11/2 configuration in Cs isotopes in the mass region A ~ 130 around neutron number N = 79. These results are in commensurate with the TRS calculations. [ABSTRACT FROM AUTHOR]

The β decay properties of the neutron-rich isotopes with neutron number N = 126, out of reach by any reaction well established so far, are very interesting from the astrophysical point of view. We will propose β decay lifetime measurements with a new isotope separation system, which is supposed to separate a single species of the radioactive nuclei among target-like fragments produced via multi-nucleon transfer reactions in binary heavy ion collisions, by using a gas catcher cell combined with laser resonance ionization technique. The present proposal aims to measure β decay properties of several nuclei around A∼200 with N = 126 and nearby nuclei by using a stable 136Xe beam on a 198Pt target. [ABSTRACT FROM AUTHOR]

The imminent commissioning of the Japan Proton Accelerator Research Complex (J-PARC) and the planned construction of the Facility for Antiproton and Ion Research (FAIR) will offer the opportunity to pursue a systematic program of high-precision and high-statistics studies in the field of hypernuclear physics. This subject will represent as well an important topic in the physics program approved for the upgraded Continuous Electron Beam Accelerator Facility (CEBAF) at the Thomas Jefferson National Accelerator Facility (JLab). A survey of the future experimental initiatives is presented, with particular emphasis on the activities that will be carried out by Italian and Japanese researchers. [ABSTRACT FROM AUTHOR]

Neutron-rich nuclei from A = 50 to A = 80 have been studied through multi-nucleon transfer reactions by bombarding 208Pb and 238U targets with beams of 48Ca, 64Ni, 70Zn and 82Se. The gamma-array CLARA coupled to the large-acceptance magnetic spectrometer PRISMA gave unambiguous identification of prompt γ rays belonging to each nucleus. The existence of the N = 32 sub-shell closure has been corroborated through the study of odd V isotopes, whereas a sizable gap at N = 34 has been evidenced from the spectroscopy of 51Ca and 52Sc. The evolution of the N = 50 shell closure far from stability has been studied down to Z = 31. With the 48Ca beam we have applied for the first time the Recoil Distance Dopple Shift technique to measure lifetimes of neutron-rich nuclei populated in multi-nucleon transfer reactions. Effective charges in the fp shell above 48Ca have been derived. The first implementation of the tracking array AGATA (the so called “Demon-strator”) will be soon coupled to the PRISMA spectrometer at Legnaro. The future prospects with the use of the Demonstrator are also presented. [ABSTRACT FROM AUTHOR]

The TRIUMF-ISAC Gamma-Ray Escape Suppressed Spectrometer (TIGRESS) is a state-of-the-art γ-ray spectrometer being constructed at the ISAC-II radioactive ion beam facility at TRIUMF. TIGRESS will be comprised of twelve 32-fold segmented high-purity germanium (HPGe) clover-type γ-ray detectors, with BGO/CsI(Tl) Compton-suppression shields, and is currently operational at ISAC-II in an early-implementation configuration of six detectors. Results have been obtained for the first experiments performed using TIGRESS, which examined the A = 20, 21, and 29 isotopes of Na by Coulomb excitation. [ABSTRACT FROM AUTHOR]

The SAGE spectrometer will combine a segmented Si-detector with a Ge-detector array aiming to take the simultaneous in-beam γ-ray and conversion electron spectroscopy to the next level. It will be coupled with the GREAT focal plane spectrometer and the RITU gas-filled recoil separator at the accelerator laboratory of the University of Jyväskylä, Finland. Its high efficiency and resolution will open the door to a new era of complete spectroscopy directed, amongst others, at the study of superheavy nuclei aiming to investigate the properties of the next spherical proton shell above Z = 82. [ABSTRACT FROM AUTHOR]

Positron-electron pair creation near the threshold energy is extremely difficult to investigate by both experiments and theory. First test experiments were performed at the ILL to determine the cross sections for positron-electron pair creation near threshold using prompt γ-rays from different targets after neutron capture and conventional radioactive sources. Pair creation was studied in a Ge detector, which simultaneously acted as sample and detector. First results are presented which show a significant deviation from theoretical values near threshold. [ABSTRACT FROM AUTHOR]

The ΛNN three-body force, through ΛN-ΣN coupling, plays an important role in the structure of Λ hypernuclei. We have been studying the ΛN interaction via hypernuclear γ-ray spectroscopy experiments and obtained the effective interaction strengths of the spin-dependent ΛN interactions. In addition, a possible effect of the ΛNN three-body force is being investigated from precise level schemes of light Λ hypernuclei. The ΛNN three-body force can also be studied from the structure of neutron-rich Λ hypernuclei by using the (π-,K+) reaction. [ABSTRACT FROM AUTHOR]

We report on our recent experimental studies of reactions relevant for the g process nucleosynthesis. Applying the activation method using the Cologne Clover Counting Setup total cross sections of the reactions 168Yb(α,γ), 168Yb(α,n), and 187Re(α,n) could be obtained. Furthermore, the reaction 89Y(p,γ) was investigated via the in-beam technique with HPGe detectors at the high-efficiency g-ray spectrometer HORUS in Cologne in order to determine partial and total cross sections. [ABSTRACT FROM AUTHOR]