A new apparatus for the study of electron impact fragmentation of molecular clusters

This paper reports on the development of a new experiment for the study of electron-impact induced dissociation and fragmentation of molecular clusters and biomolecules and other species solvated in water clusters. The purpose is to look at clusters that are of interest to biophysics, atmospheric physics, and other fields. The experiment consists of a differentially pumped vacuum system, with an expansion chamber to generate a pulsed supersonic beam of clusters, and a collision chamber where the cluster beam intersects with an electron beam. Water clusters can be seeded with biomolecules emerging from a resistively heated oven. Investigation will be possible into both ion yields and long-lived neutral metastable yields produced by electron-impact fragmentation of relevant clusters and biomolecules.