Electron Induced Vibrational Deexcitation of the Molecular Ions H 2 + and D 2 +

Abstract

The interaction of molecular ions with low kinetic energy electrons has been studied extensively at different heavy-ion storage rings during the last ten years. The usage of storage rings made it possible to store infrared-active molecular ion beams, such as HD+, for a time that is sufficiently long so that these ions are completely relaxed to their vibrational ground state by spontaneous emission of radiation. The stored ion beams are then merged with an intense and cold electron beam by using the electron cooling device present in the ion storage ring as a target for electron-ion collision studies. Here we report on the extension of such experiments to the homonuclear hydrogen ions which do not cool radiatively and for which we hence can study electron-impact vibrational de-excitation.