Doubly Excited States in Helium Close to the Double Ionization Threshold: Angular and Energy Resolved Partial Cross Sections
نویسندگان
چکیده
This is a report about a novel experiment on double excitation of Helium by absorption of synchrotron radiation close to the double ionization threshold at 79 eV. Partial cross-sections for single-ionization from 78.15 eV up to 78,9 eV (photon energy) with an energy resolution of 3meV have been measured. The technique described in this article allows for an angular and energy resolved measurement of low energy electrons with a high detection efficiency due to an angular acceptance of 4 solid angle.
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