First -and -spectroscopic decay studies of the N 82 r-process ''waiting-point'' nuclide 130 Cd have been performed at CERN/ISOLDE using the highest achievable isotopic selectivity. Several nuclear-physics surprises have been discovered. The first one is the unanticipatedly high energy of 2.12 MeV for the [g 9=2 g 7=2 1 level in 130 In, which is fed by the main Gamow-Teller transition. The second surprise is the rather high Q value of 8.34 MeV, which is in agreement only with recent mass models that include the phenomenon of N 82 shell quenching. Possible implications of these new results on the formation of the A ' 130 r-process abundance peak are presented.

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The isotopes 68 74 Ni, of interest both for nuclear physics and astrophysics, have been produced in proton-induced fission of 238 U and ionized in a laser ion guide coupled to an on-line mass separator. Their b decay was studied by means of b-g and g-g spectroscopy. Half-lives have been determined and production cross sections extracted. A partial level scheme is presented for 73 Cu and additional levels for 71 Cu, providing evidence for a sharply lowered position of the p1f 5͞2 orbital as occupancy of the n1g 9͞2 state increases. The latter may have a clear impact on the predicted structure and decay properties of doubly magic 78 Ni. [S0031-9007 (98)07340-2]

The new proton radioactivities 165,166,167 Ir and 171 Au have been observed. The Ir isotopes were produced via the 92 Mo( 78 Kr,pxn) 165,166,167 Ir reactions at 357 and 384 MeV. 171 Au was produced via the 96 Ru( 78 Kr,p2n) 171 Au reaction at 389 MeV. The proton emitters were each identified by position, time, and energy correlations between the implantation of a residual nucleus into a double-sided silicon strip detector, the observation of a decay proton, and the subsequent observation of a decay alpha particle from the daughter nucleus ͑ 164,165,166 Os and 170 Pt, respectively͒. Both 166 Ir and 167 Ir have proton-emitting ground and isomeric states, which also decay by alpha emission. The proton-decay rates have been reproduced by calculations using the WKB barrier penetration approximation and a low-seniority shell-model calculation of the spectroscopic factors. The alpha decays of the four nuclei are followed by chains of alpha decays, allowing the determination of single-particle orbital orderings. Mass information has also been obtained from the alpha-decay chains because a connection to a known mass can be obtained for one of the nuclei. Ground-state mass excesses are reported for 151 Tm, 154 Yb, 155 Lu, 158 Hf, 159 Ta, 162 W, 163 Re, 166 Os, 167 Ir, and 170 Pt. The mass excess for 171m Au is also given. Proton separation energies are also deduced for the odd-Z alpha daughter nuclei of the Ir proton emitters.

The yields of over 200 projectile-like fragments (PLFs) and target-like fragments (TLFs) from the interaction of (E c.m. =450 MeV) 136 Xe with a thick target of 208 Pb were measured using Gammasphere and off-line γ-ray spectroscopy, giving a comprehensive picture of the production cross sections in this reaction.The measured yields were compared to predictions of the GRAZING model and the predictions of Zagrebaev and Greiner using a quantitative metric, the theory evaluation factor, tef. The GRAZING model predictions are adequate for describing the yields of nuclei near the target or projectile but grossly underestimate the yields of all other products. The predictions of Zagrebaev and Greiner correctly describe the magnitude and maxima of the observed TLF transfer cross sections for a wide range of transfers (∆Z = -8 to ∆Z = +2). However for ∆Z =+4, the observed position of the maximum in the distribution is four neutrons richer than the predicted maximum. The predicted yields of the neutron-rich N=126 nuclei exceed the measured values by two orders of magnitude. Correlations between TLF and PLF yields are discussed.