Application of Accelerators in Research and Industry

Application of Accelerators in Research and Industry - J.L Duggan

Complex molecular systems such as large molecules or clusters are characterised by a large number of degrees of freedom. Energies well in excess of individual thresholds for fragmentation can be stored for long times and metastable excited states become important. We will concentrate in this paper on the study of the response of such nanoscale systems, i.e. we will study excitation and fragmentation mechanisms induced by highly charged ion radiation, reflecting dynamic energy and charge flow processes. We will illustrate these relaxation processes for different molecular systems from Polycyclic Aromatic Hydrocarbons, water or biomolecule targets and their clusters in collision with multiply charged ions. We will emphasize that slow multiply charged ions provide an efficient way to study the stability of complex systems. Indeed, such ions are known to remove several electrons at large impact parameters resulting in a fast and gentle ionization.