  We studied the magnetic field dependence of the inelastic decay of an
ultracold, optically trapped 6-Li gas of different spin compositions. The spin
mixture of the two lowest hyperfine states showed two decay resonances at 550 G
and 680 G due to two-body collisions, close to the predicted Feshbach resonance
of the elastic s-wave collisions at 800 G. The rapid decay near Feshbach
resonances found in bosonic gases was found to be suppressed by the Pauli
exclusion principle. The observed lifetimes of several hundred milliseconds are
much longer than the expected time for Cooper pair formation and the phase
transition to superfluidity in the vicinity of the Feshbach resonance.
