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A measurement was performed at the white neutron source Geel Linear Accelerator (GELINA) of the Institute for Reference Materials and Measurements to determine the cross sections for the (n, n'γ) and (n, 2n'γ) reactions on 56Fe. The Gamma Array for Inelastic Neutron Scattering (GAINS) was used. The results are scaled to the neutron-induced fission cross section of 235U. The paper emphasizes the multiple checks performed to assure the consistency of the results. γ production cross sections, total inelastic cross sections, and level production cross sections were determined. A good agreement exists with previous measurements. Theoretical calculations were performed with the talys 1.6 reaction code using default parameters, but also using a microscopic approach. These calculations are discussed in comparison t [ABSTRACT FROM AUTHOR]

The nuclear structure of 69Cu has been investigated by means of the (d, ³He) transfer reaction at the Orsay tandem in direct kinematics using a deuteron beam at Ed = 27 MeV and a target of 70Zn isotopically enriched to 95.4%. The ³He of interest from the transfer reaction were detected with the split-pole spectrometer at different angles in the laboratory frame in order to perform angular distributions and assign the angular momentum for each populated state in 69Cu. In this paper, the transferred angular momenta of the populated states will be presented. [ABSTRACT FROM AUTHOR]

Abstract: Gamma production cross-sections were measured for the neutron inelastic scattering and () reactions on 209Bi using the white neutron spectrum of GELINA with the time-of-flight technique at the 200 m flight-path station. The full energy range, from the inelastic threshold up to 20 MeV was covered in one experiment with an unprecedented energy resolution of 1.1 keV at 1 MeV and 35 keV at 10 MeV. The gamma-rays were detected with large volume HPGe detectors. The flux was determined with a 235U fission chamber based on the 235U() standard cross-section. A metallic Bi sample was used. Inelastic gamma production cross-sections were measured for 39 transitions up to an excitation energy of 3.8 MeV. Based on the adopted level scheme of 209Bi, the total inelastic and the level cross-sections were constructed. A total uncertainty smaller than 5% was obtained for the total inelastic cross-section up to 10 MeV. The gamma production cross-section was measured for the 8 transitions from 208Bi nucleus up to 1.09 MeV excitation energy. The results are compared with earlier experimental works and with model calculations performed with the TALYS code, version 0.72. Calculations with the TALYS model code show good agreement with the deduced total inelastic cross-section in the entire incident energy range and for deduced level cross-sections below 3 MeV. Discrepancies between calculation and experiment that occur for gamma production cross-sections above 3 MeV are discussed. [Copyright &y& Elsevier]

We report the results from the first experiment to measure gyromagnetic factors of μs isomers in neutron-rich nuclei produced by intermediate-energy projectile-fragmentation reactions. The Time Dependent Perturbed Angular Distribution (TDPAD) method was applied in combination with the heavy-ion-gamma correlation technique. The nuclides in the vicinity of 68Ni were produced and spin-oriented following the fragmentation of a 76Ge, 61.4 MeV/u beam at GANIL. The results obtained, |g|(69mCu) = 0.225(25) and |g|(67mNi) = 0.125(6) provide another indication of the importance of proton excitation across the Z = 28 shell gap for the description of these states. [ABSTRACT FROM AUTHOR]

The strength functions of the π f 5 / 2 , π p 3 / 2 and π f 7 / 2 orbitals in neutron-rich 71 Cu were obtained in a 72 Zn(d, 3 He) 71 Cu proton pick-up reaction in inverse kinematics using a radioactive beam of 72 Zn at 38 MeV/u. A dedicated set-up was developed to overcome the experimental challenges posed by the low cross section of the reaction and the low energy of the outgoing 3 He particles. The excitation-energy spectrum was reconstructed and spectroscopic factors were obtained after analysis of the angular distributions with the finite-range Distorted-Wave Born Approximation (DWBA). The results show that unlike for the π f 5 / 2 orbital and contrary to earlier interpretation, the π f 7 / 2 single-particle strength distribution is not appreciably affected by the addition of neutrons beyond N = 40 . [ABSTRACT FROM AUTHOR]

The design of generation IV nuclear reactors and the studies of new fuel cycles require knowledge of the cross sections of various nuclear reactions. Our research is focused on (n,xnγ) reactions occurring in these new reactors. The aim is to measure unknown cross sections and to reduce the uncertainty on present data for reactions and isotopes of interest for transmutation or advanced reactors. The present work studies the 235U(n, n'γ) and 235U(n, 2nγ) reactions in the fast neutron energy domain (up to 20 MeV). The experiments were performed with the Geel electron linear accelerator GELINA, which delivers a pulsed white neutron beam. The time characteristics enable measuring neutron energies with the time-of-flight (TOF) technique. The neutron induced reactions [in this case inelastic scattering and (n, 2n) reactions] are identified by on-line prompt γ spectroscopy with an experimental setup including four high-purity germanium (HPGe) detectors. A fission ionization chamber is used to monitor the incident neutron flux. The experimental setup and analysis methods are presented and the model calculations performed with the TALYS-1.2 code are discussed. [ABSTRACT FROM AUTHOR]

We report here the first direct lifetime measurement of the 2+ state in 72,74Zn. The neutron-rich beam was produced by in-flight fragmentation of 76Ge at the Grand Accélérateur National d'Ions Lourds and separated with the LISE spectrometer. The 2\ state was excited by inelastic scattering and knock-out reaction on a CD2 target and its lifetime was measured by the recoil-distance Doppler-shift method with the Köln plunger device combined with the EXOGAM detectors. The lifetimes of the 2* states in 72,74Zn were determined to be 17.9(18) and 27.0(24) ps, which correspond to reduced transition probabilities B(E2\2\ -> 0+) = 385(39) and 370(33) e2 fm4, respectively. These values support the idea of a systematic maximum of collectivity at N = 42 for Zn, Ge, and Se nuclei. In addition, the available systematics in the neighboring nuclei point toward a transition from a spherical oscillator at N = 40 to complete y-softness at N = 42. [ABSTRACT FROM AUTHOR]

Abstract: In a series of experiments at the SISSI/LISE3 facility of GANIL conducted between 1999 and 2004, we have collected decay information for proton-rich nuclei between 36Ca and 56Zn. The data allowed us to study the decay properties of 26 nuclei. The main experimental information obtained for all nuclei is their β-decay half-life and their total β-delayed proton emission branching ratio. For many nuclei, individual proton groups and γ rays were identified and allowed us to establish first partial decay schemes for some of the nuclei studied. In addition, mass-excess values have been determined for some of the nuclei by means of the isobaric multiplet mass equation. For 50Ni, the decay via β-delayed two-proton emission could be tentatively identified. The decay of 49Ni allowed for the first time to identify the first state in 48Fe. The experimental data are confronted to model predictions for the half-life and the mass-excess values. [Copyright &y& Elsevier]

Transfer reactions are verified to be an important tool for the study of light unbound nuclei. We have studied the proton-rich nuclei 9C and 15F respectively through the 10B(14N, 15C)9C and 16O(14N, 15C)15F reactions. Resonance energies and widths were obtained for the first levels of the unbound 15F nucleus. The angular distributions corresponding to these resonances were analysed using the coupled-channels transfer code FRESCO. For the bound 9C nucleus only the ground state was observed. [Copyright &y& Elsevier]

Proton reaction cross-section measurements on various stable and neutron-rich nuclei (4,6He, 7–9Li, 9–11Be, 21–24F, 22–26Ne, 25–29Na and 29–32Mg) were performed via the attenuation method at intermediate energies (∼35–75AMeV) and using a cryogenic hydrogen target. The results are discussed in the framework of different approaches of the nucleon–nucleus potential. [Copyright &y& Elsevier]