Time and position sensitive photon detector for coincidence measurements in the keV energy range

The detection efficiency η of any particle detector is important, concerning acquisition time, but becomes even more critical when two particles are detected in coincidence, with a total efficiency η₁η₂, in order to allow a deeper understanding of complex processes induced by light or particle interaction with matter. Efficiency and resolution of a time and position sensitive x-ray detector are reported here. This system consists of a multilayer transmission photocathode and two micro-channel plates (MCPs) equipped with a delay line anode (DLA). The efficiency is found to be about 20% for Al Kα photons, while the spatial resolution is comparable to that of a standard DLA detector (about 100 μm). The fast response time of the detector combined with its efficiency should allow coincidence experiments between x-ray photons and other particles (electron, ions, etc.).