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7Li induced-reactions have been used with a 186W target to populate nuclei around A∼180-190 at the National Institute of Physics and Nuclear Engineering in Bucharest, Romania. An array of high-purity germanium (HPGe) and cerium-doped lanthanum bromide (LaBr3:Ce) detectors have been used to measure sub-nanosecond half-lives with fast-timing techniques. The yrast 2+ state in 190Os was measured to be t1/2 = 375(20)ps, in excellent agreement with the literature value. The previously unreported half-life of the 564-keV state in 189Ir has also been measured and a value of t1/2 = 540(100)ps ps obtained. [ABSTRACT FROM AUTHOR]

The half-lives of the TZ = -2, 56Zn and TZ = -1, 58Zn isotopes and other nuclei were measured in a β-decay experiment at GANIL. The energy levels populated by the 56Zn β decay were determined. The 56Zn results are compared with the results of the mirror process, the charge exchange reaction 56Fe(3He,t)56Co. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions can be studied in both β decay and charge exchange (CE) reactions. If isospin is a good quantum number, then the Tz = -1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the TZ = -1 fp-shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (33He, t) measurements on the mirror TZ = +1 target nuclei studied in high resolution at RCNP, Osaka. The β decay experiments were performed as part of the STOPPED beam RISING campaign at GSI. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions can be studied in both β decay and charge exchange (CE) reactions. If isospin is a good quantum number, then the Tz = -1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the Tz = -1 fp-shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (3He, t) measurements on the mirror Tz = +1 target nuclei studied in high resolution at RCNP, Osaka. The β decay experiments were performed as part of the STOPPED beam RISING campaign at GSI. [ABSTRACT FROM AUTHOR]

Due to the simplicity of the στ operator that causes Gamow-Teller (GT) transitions, they are the most popular nuclear weak process in the Universe. The GT transitions in pf-shell nuclei, for example, starting from stable Tz = +1 and proton-rich Tz = +1 nuclei, where Tz = (N-Z)/2, play important roles in the supernova-explosion or rp-process nucleosynthesis. In the β-decay study of pf-shell nuclei, half-lives can be measured rather accurately. On the other hand, in a high-resolution (3He, t) charge-exchange reaction at 0°, individual GT transitions up to high excitations can be studied. In order to derive reliable GT transition strengths B(GT), we present a unique analysis that combines the strength distribution form the (3He, t) measurement with the information from the study of mirror β decay, where good isospin symmetry of Tz = ±1→0 transitions is assumed. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions can be studied in both β-decay and charge exchange(CE) reactions. If isospin is a good quantum number, then the Tz = -1→0 and Tz = +1→0 GT mirror transitions, are identical. Therefore, a comparison of the results from studies of β decay and CE should shed light on this assumption. Accordingly we have studied the β decay of the Tz = -1 fp-shell nuclei, 54Ni, 50Fe, 46Cr, and 42Ti, produced in fragmentation and we have compared our results with the spectra from (3He, t) measurements on the mirror Tz = +1 target nuclei studied in high resolution at RCNP, Osaka. The β-decay experiments were performed as part of the STOPPED beam RISING campaign at GSI. [ABSTRACT FROM AUTHOR]

This conference paper outlines the operation and some of the preliminary physics results using the GSI RISING active stopper. Data are presented from an experiment using combined isomer and beta-delayed gamma-ray spectroscopy to study low-lying spectral and decay properties of heavy-neutron-rich nuclei around A∼190 produced following the relativistic projectile fragmentation of 208Pb primary beam. The response of the RISING active stopper detector is demonstrated for both the implantation of heavy secondary fragments and in-situ decay of beta-particles. Beta-delayed gamma-ray spectroscopy following decays of the neutron-rich nucleus 194Re is presented to demonstrate the experimental performance of the set-up. The resulting information inferred from excited states in the W and Os daughter nuclei is compared with results from Skyrme Hartree-Fock predictions of the evolution of nuclear shape. [ABSTRACT FROM AUTHOR]

The nuclear structure of neutron-rich N>=126 nuclei have been investigated following their production via relativistic projectile fragmentation of a E/A = 1 GeV 238U beam on a Be target. The cocktail of secondary beam products were separated and identified using the GSI FRagment Separator (FRS). The nuclei of interest were implanted in a high-granularity active stopper detector set-up consisting of 6 double sided silicon strip detectors. The associated gamma-ray transitions were detected with the RISING array, consisting of 15 Euroball cluster Ge-detectors. Time-correlated gamma decays from individually identified nuclear species have been recorded, allowing the clean identification of isomeric decays. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions starting from stable as well as unstable pf-shell nuclei are of interest not only in nuclear physics, but also in astrophysics, e.g. in violent neutrino-induced reactions at the core-collapse stage of type II supernovae. In the β-decay study of these pf-shell nuclei, half-lives can be measured rather accurately. On the other hand, in high-resolution (3He,t) charge-exchange reactions at 0°, individual GT transitions up to high excitations can be studied. Assuming the isospin symmetry for the strengths of Tz = ±1→0 analogous GT transitions, we present a unique “merged analysis” for the determination of absolute B(GT) values. This method can be applied not only to T = 1 systems, but also to higher T systems. [ABSTRACT FROM AUTHOR]

Gamow-Teller (GT) transitions starting from unstable pf-shell nuclei play important roles in neutrino-induced reactions that happen under the extremely high temperature conditions in core-collapse (type II) supernovae. In the β decay, it is difficult to obtain GT strengths B(GT) to higher excited states, but accurate half-lives can be measured. On the other hand, high-resolution (3He,t) charge-exchange reactions at 0° and at 420 MeV yield cross-sections, that are proportional to B(GT) values, for individual transitions up to high excitation. Assuming isospin symmetry, we performed a unique analysis to determine absolute B(GT) values for the Tz = ±1→0 analogous GT transitions. Further β-decay studies for unstable pf-shell nuclei to obtain accurate half-lives and feeding ratios are in progress. [ABSTRACT FROM AUTHOR]

This contribution reports on the results of an experiment to study the near-yrast states in selenium- and osmium-like nuclei, following their population in thick-target, multinucleon transfer reactions between an 82Se beam and a 192Os target. The experimental results for the level scheme for 84Se are presented together with investigations into the use of multi-dimensional gamma-ray energy gating to investigate angular momentum population in such heavy-ion binary reactions. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

We have developed a new experimental setup based at the GANIL/SPIRAL facility in Caen, France to measure one-nucleon transfer reactions in inverse kinematics in order to study the evolution of the single particle structure of exotic nuclei. The setup couples together three state-of-the-art detection systems: the TIARA Si array, the large-acceptance magnetic spectrometer VAMOS and the high-efficiency segmented Ge γ-ray array EXOGAM. In a first experiment, the 24Ne(d,p)25Ne reaction has been studied to probe the N=16 shell closure. Details of the setup, data analysis and preliminary results are presented. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

The TIARA+VAMOS+EXOGAM set-up has recently been installed at GANIL to study the single-particle structure of exotic nuclei. The unique characteristics of the TIARA array, combined with the large acceptance spectrometer VAMOS and the high efficiency Germanium detector array EXOGAM, has allowed high-resolution measurements of transfer reactions in inverse kinematics using low intensity exotic beams. We will describe the experimental set-up, data analysis and preliminary results of the first experiments using a 24Ne beam from SPIRAL, concentrating in particular on the performance of VAMOS that has been used to detect the heavy fragments after the (d,p), (d,d) and (d,t) reactions. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

This contribution reports on the results of an experiment to study the near-yrast states in selenium isotopes around N=50, following their population in thick-target, multinucleon transfer reactions between an 82Se beam and a 192Os target. Discrete decays from states with spins of 20h and higher are clearly identified in the Os-like fragments. Information on the size of the energy gap between the f5/2 and p3/2 proton orbitals can be inferred from the spectroscopy of the N=48 isotone, 82Se. The experiment results for the level schemes for 80,82Se derived in the current work are compared with restricted-basis shell model calculations, which give a good description of the yrast sequences of these nuclei using a basis space limited to excitations in the (p3/2 , p1/2 , g9/2 ) neutron and (f5/2 , p3/2 , p1/2 ) proton orbitals. © 2006 American Institute of Physics [ABSTRACT FROM AUTHOR]

Multinucleon transfer reactions between a thin 100Mo target and a 136Xe beam at an energy of 700 MeV have been used to investigate the evolution of structure with increasing angular momentum in a range of nuclei with A∼100. The use of kinematically complete experiments coupled with isomer tagging allow the selection of specific exit channels. The evolution from quasi-vibrational states at low spins to quasi-rotational structures following the population of a low-Ω, ‘rotationally aligned’ h11/2 neutron configuration is demonstrated to be a standard feature of the region using the so-called E-Gamma Over Spin (E-GOS) empirical prescription. This treatment is extended to odd-A nuclei. [ABSTRACT FROM AUTHOR]

A new Total Absorption Spectrometer (TAS) called “Lucrecia” has been installed at ISOLDE (CERN) to investigate the β-decay of some nuclei with A≈70–80 in the vicinity of the N=Z line. In this work we report on the decay of the N=Z nucleus 76Sr, measured with a TAS for the first time. The Gamow-Teller strength distribution B(GT) for this decay is presented and compared with theoretical calculations. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In order to determine the Gamow-Teller strength distribution for the N = Z nucleus 72Kr an experiment was performed with a Total Absorption Gamma Spectrometer. To fully accomplish this task it is crucial to determine the multipolarity of the low energy transitions as the spin-parity of the daughter ground state has been debated. This is done by experimental determination of the conversion coefficients. Preliminary results for the multipolarity and conversion coefficients of the transition connecting the isomeric state at 101 keV with the 72Br ground state are presented. [ABSTRACT FROM AUTHOR]