Studies of fast negative ions in superfluid helium

Abstract

The normal negative ion in liquid helium consists of an electron confined in a bubble of radius approximately 19 Å. These bubbles have been studied in many experiments. Time-of-flight mobility measurements have revealed that there are other types of negative ion of higher mobility and unknown structure. In this note we report on a study of the fastest of these and discuss the conditions under which it can be observed. © Published under licence by IOP Publishing Ltd.