Electron Induced Fluorescence Apparatus (EIFA)
The EIF experiment is aimed at studying excitation reactions of electrons with molecules by analysis of photon emission of the deexciting species. Such processes are abundant in many environments from laboratory and industry (electrical discharges, plasmas) to atmospheres of planets (aurora borealis, lightnings, upper atmosphere processes) and space (stars, nebulae, comet comas, …). The experiment provides reference data for evaluation of emission spectra of these natural phenomena and laboratory/industrial light sources and provides basic data on electron-molecule collisions such as reaction kinetics and cross sections.
The experimental setup is based on crossed beams of electrons and molecules in the vacuum. The electron beam is generated by either an electron gun or trochoidal electron monochromator with energetic resolution of ~300meV and the molecular beam of ambient temperature is formed by effusive capillary (Fig. 1.). These collide in the reaction chamber at low pressures ensuring single collision conditions where various excited species are generated. The photons emitted during their deexcitation are guided by the optical system out of the vacuum chamber into one of the optical monochromators (0.25m Czerny-Turner with optical resolution up to 0.4nm or 1.5m Czerny-Turner with resolution up to 0.002nm) and collected by the photomultiplier tube working in the photon counting regime. The experimental setup provides outstanding sensitivity allowing detection of very weak processes.
Examples of the measured compounds:
Fig. 1. Simplified scheme of the EIF experimental setup and emission spectrum of hydrogen induced by electron impact.
RNDr. Juraj Országh, PhD.
Phone Nr: +421 2 602 95 398
Prof. Dr. Štefan Matejčík, DrSc.
Phone Nr: +421 2 602 95 686
The Open University (UK), Department of Physical Sciences, Nigel Mason
Auburn University (USA), Department of Physics, Dennis Bodewits
EMPA (Switzerland), Laboratory for Mechanics of Materials and Nanostructures, Ivo Utke
University of Innsburck (Austria), Institute for Ion Physics and Applied Physics, Paul Scheier, Andreas Mauracher
This project has received funding from the European Union’s Horizon 2020 research and innovation programme under grant agreement No 871149.