Velocity map photoelectron-photoion coincidence imaging on a single detector

LaserLaB Amsterdam, VU University Amsterdam, de Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
The Review of scientific instruments (Impact Factor: 1.61). 09/2012; 83(9):093103. DOI: 10.1063/1.4749843
Source: PubMed


Here we report on a new simplified setup for velocity map photoelectron-photoion coincidence imaging using only a single particle detector. We show that both photoelectrons and photoions can be extracted toward the same micro-channel-plate delay line detector by fast switching of the high voltages on the ion optics. This single detector setup retains essentially all the features of a standard two-detector coincidence imaging setup, viz., the high spatial resolution for electron and ion imaging, while only slightly decreasing the ion time-of-flight mass resolution. The new setup paves the way to a significant cost reduction in building a coincidence imaging setup for experiments aiming to obtain the complete correlated three-dimensional momentum distribution of electrons and ions.

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