Lifetimes and collisional quenching cross sections of single rotational states in bromine

Lifetimes and self-quenching cross sections of individual rotational levels in the B 3Pi/sub 0+u/ state of 79Br2 and 81Br2 were measured by observing the fluorescence decay following excitation by acousto-optically chopped, single mode Ar+ and Kr+ lasers. The results, which depend strongly on v' and J', were interpreted in terms of gyroscopic predissociation. This type of predissociation, exhibiting maxima in the neighborhood of v'=33 and v'< or approx. =18, appears to be much stronger in bromine than in iodine