  The nucleus 54Zn has been observed for the first time in an experiment at the
SISSI/LISE3 facility of GANIL in the quasi-fragmentation of a 58Ni beam at 74.5
MeV/nucleon in a natNi target. The fragments were analysed by means of the
ALPHA-LISE3 separator and implanted in a silicon-strip detector where
correlations in space and time between implantation and subsequent decay events
allowed us to generate almost background free decay spectra for about 25
different nuclei at the same time. Eight 54Zn implantation events were
observed. From the correlated decay events, the half-life of 54Zn is determined
to be 3.2 +1.8/-0.8 ms. Seven of the eight implantations are followed by
two-proton emission with a decay energy of 1.48(2) MeV. The decay energy and
the partial half-life are compared to model predictions and allow for a test of
these two-proton decay models.
