The dissociative excitation of MeI and MeBr is investigated by He flowing afterglow technique. The relative populations of various electronically excited products were estimated The formation rate constants of CH(A), CH(B) and CH(C) are obtained from reaction of He(23S) with MeI. The rotational populations of CH(A2D,u' = 0) can be represented in terms of a Boltzmann distribution.

Key words: REACTION MECHANISM, REACTION KINETICS, EXCITED STATE, IODIDE ION, HELIUM, EXCITATION PROCESSES, METASTABLE STATES, BROMIDE ION, PHOSPHORYLASE, MOLECULAR DISSOCIATION