Schöffler, M. S.Jahnke, T.Waitz, M.Trinter, F.Lenz, U.Stuck, C.Jones, M.Pindzola, M. S.Belkacem, A.Cocke, C. L.Landers, A.Colgan, J.Kheifets, A.Bray, I.Schmidt-Böcking, H.Dörner, R.Weber, Th2023-12-072023-12-072014-04-01https://hdl.handle.net/2097/43918In a kinematically complete experiment we have measured the photo double ionization of Helium at a photon energy of 800 eV and observed He2+ ions with 0 momentum, corresponding to a back-to-back-emission of the two electrons. The results are in good agreement with theoretical calculations.Creative Commons Attribution 3.0 licencehttps://creativecommons.org/licenses/by/3.0/Text