Dependence of ion pair formation on the velocity of high rydberg state argon atoms in collisions with CCl

Ionisation of argon atoms in high Rydberg states (HR) by collisions with CCl4 and CCl3F has been investigated. Absolute cross sections for the dissociative electron attachment are reported, together with the identities of the negatively and positively charged species produced in coincidence in the collision. The dependence of the cross sections on the principal quantum number n and the HR argon velocity alows us to determine the limits of the theoretical "free electron" model and the role of the core Ar+ in the outcome of the reaction