Electric-field effects in photodetachment from Cl- and S- ions in a microwave field

Photodetachment from negative chlorine and sulfur ions has been studied in the presence of electric fields ranging from 0.5 to 2.7 kV/cm. While the applied electric field oscillated at 2.7 GHz, the data are consistent with the assumption that the field was constant during each detachment event. A simple model for the photodetachment cross section in a constant electric field is presented, appropriate to any ion where zero-field detachment is dominated by an s-wave continuum. The model is in good agreement with the data.