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Neutron deficient nuclei near [sup 100]Sn have been produced by projectile fragmentation of a 1 A-GeV [sup 112]Sn beam in a beryllium target. The fragments were separated in the magnetic spectrometer FRS at GSI, Darmstadt. The unambiguously identified ions were stopped in a highly segmented silicon strip detector stack which was designed to measure the halflives and the total energy of emitted particles with very low background and high efficiency. We were able to study [sup 102]Sn in decay spectroscopy for the first time and establish a decay scheme for the daughter nuclide [sup 102]In. With the measurement of the halflife and the Q-value the Gamov-Teller strength could be deduced. Additionally the Q-value of [sup 98]Cd was measured with high precision and we obtained the halflives of [sup 101]Sn, [sup 103]Sn and [sup 100]In and the absolute branching ratio of beta-delayed proton emission of [sup 101]Sn. We report halflives of rp-process waiting point nuclei between [sup 80]Zr and [sup 92,93]Pd and the observation of very fast decays for the heaviest odd-odd N=Z nuclei, [sup 90]Rh, [sup 94]Ag and [sup 98]In, in agreement with superallowed Fermi transitions. In addition halflives of [sup 75]Sr, [sup 77]Y, [sup 79]Zr, [sup 83]Mo, [sup 87]Tc, [sup 91,92,93]Rh and [sup 99]In were measured. Finally, with our highly efficient identification system we were able to identify two new nuclei, [sup 76]Y and [sup 78]Zr, close to the proton dripline. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Properties of exotic nuclei like atomic masses, decay modes, and half-lives can be ideally investigated in storage rings and ion traps. Some experiments can be carried out under conditions which prevail in hot stellar plasmas. The experimental potential of storage and cooling of exotic nuclei is illustrated with recent experimental results and an outlook to future experiments is presented. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Schottky Mass Spectrometry turned out to be an excellent tool for systematic nuclear mass measurements. The newly developed data acquisition system [1] which yields several advantages for the data analysis, was used for the first time in Nov. 1997. Instead of online Fourier transformation as in former measurements [2,3] the signal is now digitized with a sampling rate of 640 kHz (16 bits of resolution) and stored as time-captures. With a continuous data rate of 1.2MB/s nearly 1TB of raw data were stored. The Fast Fourier Transformation offline analysis allows the study of the dynamical behavior of the stored ions in the ESR including cooling forces and decay. The new spectra contain enough reference nuclei to determine the deviations from the constant momentum compaction factor α[sub p]. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present a new method for precise mass measurements of short-lived hot nuclei. These nuclei were produced via projectile fragmentation, separated with the FRS and injected into the storage ring ESR being operated in the isochronous mode. The revolution time of the ions is measured with a time-of-flight detector sensitive to single particles. This new method allows access to exotic nuclei with half-lives in the microsecond region. We report on first results from this novel method obtained with measurements on neutron-deficient fragments of a chromium primary beam with half-lives down to 50 ms. A precision of δm/m≤5·10[sup -6] has been achieved. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]