Heidelberg 2015 – wissenschaftliches Programm
A 32.1: Hauptvortrag
Donnerstag, 26. März 2015, 14:30–15:00, C/HSW
Time-Resolved Measurement of Interatomic Coulombic Decay in Ne2 — •Kirsten Schnorr — Max-Planck-Institut für Kernphysik, Heidelberg
Interatomic Coulombic Decay (ICD) is a radiationless relaxation mechanism where deexcitation of one atom is achieved via energy transfer to a weakly bound neighbouring atom, which then emits an electron. The process has been theoretically predicted by Cederbaum et al. in 1997 and experimentally confirmed in clusters and molecules a few years later. Although the decay time of ICD is a crucial parameter for understanding the underlying mechanism, no time-resolved investigation was performed so far.
In our measurement we determine the ICD lifetime in Ne2: A 58 eV pump pulse of approximately 60 fs creates a 2s hole at one of the Ne atoms, thereby initiating the decay process, which is then probed after an adjustable time delay by an exact copy of the first pulse. Only if the decay has happened by the time the probe pulse arrives, a certain energy level may be populated. This leads to a characteristic fragmentation channel that can be separated by using a Reaction Micrsoscope, which allows us to study charged particles in coincidence.