FIRST SPECTROSCOPIC STUDY OF SI-22

In an experiment at the LISE3 facility of GANIL, we produced the proto n-rich isotope Si-22 by the fragmentation of a Ar-36 primary beam at 9 5 MeV/nucleon. After implantation in a detector telescope, we studied the decay of Si-22 via a measurement of charged particles emitted duri ng the decay. The most important beta-delayed proton activity is obser ved at an energy of E(p) = (1.99+/-0.05) MeV with a branching ratio of (20 +/-2)%. The spectra allow us also to determine the half-life of S i-22 to be T-1/2 = (29 +/- 2) ms. These results are compared with theo retical estimates and model predictions.