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Excited states in 129I were populated with the 124Sn(7Li,2n) reaction at 23 MeV. In-beam measurements of γ-ray coincidences were performed with an array of eight HPGe detectors and five LaBr3(Ce) scintillation detectors. Based on the γγ coincidence data, a positive parity band structure built on the 7/2+ ground state was established and the nπg7/2 configuration at oblate deformation was assigned to it. The results are compared to interacting Boson-Fermion model (IBFM) and total Routhian surface (TRS) calculations. [ABSTRACT FROM AUTHOR]

Background: Nuclei in the A " 190 mass region show gradual shape changes from prolate through nonaxial deformed shapes and ultimately towards spherical shapes as the Pb region is approached. Exploring how this shape evolution occurs will help us understand the evolution of collectivity in this region. Purpose: The level scheme of the 192 Au nucleus in A "190 region was studied in order to deduce its deformations. Methods: High-spin states of 192Au have been populated in the 186W("B, 5n) reaction at a beam energy of 68 MeV and their ? decay was studied using the YRAST Ball detector array at the Wright Nuclear Structure Laboratory (WNSL), Yale University. Results: Based on double and triple ?-ray coincidence data the level scheme of 192 Au has been extended up to Ip = 32+ at an excitation energy of ~6 MeV. Conclusion: The results are discussed in the framework of pairing and deformation self-consistent total Routhian surface (TRS) and cranked shell model (CSM) calculations. The comparison of the experimental observations with the calculations indicates that this nucleus takes a nonaxial shape similar to other Au nuclei in this region. [ABSTRACT FROM AUTHOR]

High level of electromagnetic radiation is produced in the interaction of relativistic ions with matter. A model to simulate it within GEANT4 has been developed in order to evaluate these sources of background and their influence on the experimental spectra. New classes have been added to the standard GEANT4 program libraries, describing the radiative electron capture, primary bremsstrahlung and secondary bremsstrahlung processes. Simulations of experiments within the RISING stopped beam campaign and comparison with the experimental results are presented. [ABSTRACT FROM AUTHOR]

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]

A precise measurement of the g factor of the first-excited state in the self-conjugate (N=Z) nucleus 24Mg is performed by a new time-differential recoil-in-vacuum method based on the hyperfine field of hydrogenlike ions. Theory predicts that the g factors of such states, in which protons and neutrons occupy the same orbits, should depart from 0.5 by a few percent due to configuration mixing and meson-exchange effects. The experimental result, g=0.538±0.013, is in excellent agreement with recent shell-model calculations and shows a departure from 0.5 by almost 3 standard deviations, thus achieving, for the first time, the precision and accuracy needed to test theory. Proof of the new method opens the way for wide applications including measurements of the magnetism of excited states of exotic nuclei produced as radioactive beams. [ABSTRACT FROM AUTHOR]