The problem of vacuum instability and creation of pairs by external fields
SU(2) is studied. The effective mass operator has complex eigenvalues implying
decay and pair creation. We consider a constant external chromoelectric field
and a region in the parameter space where the vaccum becomes unstable and
decays in pairs. Although the calculation is done in SU(2) color group it is
also valid for SU(3).Comment: 5 pages, 1 figure, to appear in Physical Review