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An overview of the main directions of present-day studies with quasimonochromatic γ beams are discussed with an emphasis on the research opportunities which will be offered at the Extreme Light Infrastructure Nuclear Physics (ELI-NP) facility at Magurele near Bucharest in Romania. Experiments with γ beams at the extremes of high temperature and high neutron-to-proton ratios are outlined. Some of the experimental setups for nuclear structure, reaction and astrophysics studies, which are available at ELI-NP, are described. Perspectives for studies of exotic nuclei within the Gamma Factory experiment at CERN are discussed. The expected fission-fragment yields at the Gamma Factory are presented. The perspectives for nuclear structure studies with γ rays with orbital angular momentum are outlined. [ABSTRACT FROM AUTHOR]

The mission of the Extreme Light Infrastructure - Nuclear Physics (ELI-NP) facility is to use extreme electromagnetic fields for nuclear physics research. At ELI-NP, high-power lasers together with a very brilliant γ-ray beam are the main research tools. Their targeted operational parameters are described. The emerging experimental program of the facility in the field of nuclear physics is reported and the main directions of the research envisioned are presented. The experimental instrumentation, which will operate at ELI-NP for the realization of the research program, is discussed. The expected impact of ELI-NP on the future advance of the field is summarized. [ABSTRACT FROM AUTHOR]

Information on the first excited states in the N = Z = 41 nucleus 82Nb sheds light on the competition of isospin T = 0 and T = 1 states in the A ∼ 80 region. The measurement was performed at the GSI laboratory using fragmentation of a 107Ag primary beam at 750 MeV/u on a 4 g/cm² 9Be target. The fragments were separated and identified unambiguously in the FRagment Separator. Three excited states were observed and the half-life estimate for the isomeric state was extracted. A tentative spin assignment based on the isobaric analogue states systematics in the Tz = 1 nucleus 82Zr, and transition probabilities indicate T = 1 character of the first two excited states, and T = 0 for the isomeric state. [ABSTRACT FROM AUTHOR]

Lifetimes of excited states in 128Ce were measured using the recoil distance Doppler-shift (RDDS) and the Doppler-shift attenuation (DSAM) methods. The experiments were performed at the Wright Nuclear Structure Laboratory of Yale University. Excited states of 128Ce were populated in the 100Mo(32Si,4n) reaction at 120 MeV and the nuclear γ decay was measured with an array of eight Clover detectors positioned at forward and backward angles. The deduced yrast transition strengths together with the energies of the levels within the ground-state (gs) band of 128Ce are in agreement with the predicted values for the X(5) critical point symmetry. Thus, we suggest 128Ce as a benchmark X(5) nucleus in the mass A ≈ 130 region. [ABSTRACT FROM AUTHOR]

Lifetimes of exited states in 134Pr were measured be means of the recoil distance Doppler-shift and Doppler-shift attenuation techniques. The experiments were performed at IReS, Strasbourg using the EUROBALL IV spectrometer, in conjunction with the inner BGO ball and the Cologne coincidence plunger apparatus. Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn(19F, 4n)134Pr. Reduced transition probabilities in 134Pr are compared to the predictions of the two quasiparticle+triaxial rotor and interacting boson fermion-fermion models. The experimental results do not support the presence of static chirality in 134Pr underlying the importance of shape fluctuations. Only within a dynamical context the presence of intrinsic chirality in 134Pr can be supported. [ABSTRACT FROM AUTHOR]

We report on the first use of post-accelerated radioactive isomeric beams. Long-lived isomeric states in 68Cu and 70Cu have been produced and separated at ISOLDE, CERN. Subsequently they were post-accelerated to 2.86 MeV/u and sent to a target in the center of the MINIBALL spectrometer, used for the detection of the γ-rays of interest. The preliminary results from the Coulomb excitation of the Iπ=6-, 1+ states in 68Cu and the Iπ=6- one in 70Cu, compared to a large-scale shell model calculations, hint the importance of the excitations across the Z=28 gap for the understanding of the nuclear structure in the neutron-rich N=40 region. [ABSTRACT FROM AUTHOR]

We report results from a pioneering experiment to measure the g factors of isomeric states of neutron-rich nuclei around [sup 68]Ni, far from the valley of β stability. For the first time, the timedependent perturbed angular distribution method was applied in combination with the heavy-ion-γ correlation technique to study g factors of spin-aligned isomers produced in a projectile fragmentation reaction and mass-separated. Some technical aspects are discussed and illustrated with preliminary results. [ABSTRACT FROM AUTHOR]

Exited states in 134Pr were populated in the fusion-evaporation reaction 119Sn( 19F, 4n) 134Pr. Recoil distance Doppler-shift and Doppler-shift attenuation measurements using the Euroball spectrometer, in conjunction with the inner BGO ball and the Cologne plunger were performed at beam energies of 87MeV and 83MeV, respectively. The measured B( E2) values within the two chiral candidates bands are not identical while the corresponding B( M1) values have a similar behaviour within the experimental uncertainties. [ABSTRACT FROM AUTHOR]

We report on the spectroscopic quadrupole moment measurement of the 7/2¡" isomeric state in "JgS27 [E* = 320.5(5) keV, Tt/2 = 415(3) ns], using the time dependent perturbed angular distribution tech-nique at the RIKEN RIBF facility. Our value, | Qs |= 23(3)

The g-factor of the ground state of 31Al (T1/2=640 ms) has been measured by the β-NMR technique on a polarized secondary fragment beam at GANIL, Caen, France. The measured value of |g|=1.517(20) is compared with sd-shell model calculations, which allows the assignment of spin and parity Iπ=5/2+ to this state. The spectroscopy of neutron-rich Al isotopes on the border of the “island of inversion” is discussed in terms of the persistence of the N=20 shell closure for Z=13 nuclei. [Copyright &y& Elsevier]