Electron-Ion-Coincidence

Recording electron and ion hits in coincidence - the electron-ion delay being essentially the ion time of flight – is a powerful technique for detailed reconstruction of the relaxation processes yielding to charged particles emission after photo-excitation of a large variety of systems in the gas phase, from atoms and molecules to clusters or nanoparticles. Single events of molecular or nanoscale-object ionization and possible eventual fragmentation are recorded individually within a momentum imaging spectrometer upon excitation with suitable light sources and eventually sorted against relevant parameters with the chance of recoil-frame reorientation of each event. This allows to study photoionization, dissociation, and chemical reactions dynamics with unprecedented detail, which motivates the current development of similar instruments at the major synchrotron radiation facilities worldwide.