Field effects on the Rydberg product-state distribution from dielectronic recombination

The effects of state mixing by extrinsic fields in the collision region have been investigated for the dielectronic recombination process ${\mathrm{Mg}}^{+}$(3s)+e→Mg(3p,nl)→Mg(3s ,nl)+hν. By field ionization of the Rydberg atoms produced, cross sections σ($n_f$) have been measured. The observed large changes of σ($n_f$) with alteration of the extrinsic field provide the first incontrovertible experimental evidence that dielectronic recombination can be changed by external fields.