AN ELECTRON-ION COINCIDENCE SPECTROMETER FOR SINGLE AND DOUBLE PHOTOIONIZATION STUDIES

A new electron ion coincidence spectrometer for the study of single an d double photoionization in the gas phase is described. The spectromet er employs a pulse scheme, which allows high mass and electron energy resolutions to be achieved simultaneously; the mass resolution is grea ter than 200 (M/Delta M, FWHM definition) and the electron energy reso lutions are 55 meV and 300 meV for studying single and double photoion ization respectively. A position-sensitive electron detector enables m ultiplex electron detection which significantly enhances the sensitivi ty of the instrument.