In an experiment at the SISSI/LISE facility of GANIL, we used the projectile fragmentation of a "Kr primary beam at 73 MeV/nucleon to produce new isotopes of astrophysical interest. We obtained clear evidence for the existence of the five new isotopes Ga, 4As, Kr, and ' Sr. However, we did not find any evidence for Br, whereas comparable nuclei were observed with more than 1000 counts. The isotope 9Br is thus deduced to be a proton-unbound nucleus with a half-life shorter than about 100 ns.

A primary beam of 58 Ni at 600 MeV͞nucleon from the SIS synchrotron at GSI was used to produce proton-rich isotopes in the titanium-to-nickel region by projectile fragmention on a beryllium target. The fragments were separated by a projectile-fragement separator and unambiguously identified. We report here the first observation of the T z 27͞2 nuclei 45 Fe and 49 Ni, the most protonrich nuclei ever synthesized with an excess of seven protons. In addition, the new isotope 42 Cr ͑T z 23͒ was identified. According to commonly used mass predictions, these isotopes are all unbound with respect to two-proton emission from their ground states. From the nonobservation of 38 Ti ͑T z 23͒ in this experiment, an upper limit of 120 ns is deduced for the half-life of this isotope. [S0031-9007(96)

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