We used the flowing afterglow technique to study the energy transfer a
nd chemical reaction processes of metastable CO(a) with CS(X) radical.
We measured the formation rate constants of CS(A) and CS(a) from the
reaction of CO(a) with CS, and they are (1.3 +/- 0.4) x 10(-11) cm3 mo
lecule-1 s-1 and (1.1 +/- 0.6) x 10(-10) cm3 molecule-1 s-1, respectiv
ely. A discussion of the formation mechanism of the electronically exc
ited fragments is presented.