INTENSITY AND LIFETIMES OF ZEKE SPECTRA

The questions addressed in this Letter are whether the lifetime or int ensity of long-lived molecular ZEKE/Rydberg states are influenced by t he intensity of background ions and hence whether these background ion s are mechanistically involved in the formation of ZEKE states. We per formed an experiment changing the ion density which had no appreciable effect on the intensity of the ZEKE signal. ZEKE states with a lifeti me of many tens of microseconds are here not changed by background ion s, either in lifetime or intensity.