Institution: | 1.Laboratory of Photonics, Tampere University of Technology, Korkeakoulunkatu 3, 33720, Tampere, Finland ;2.Helsinki Institute of Physics, Gustaf Hällströmin katu 2, 00014, Helsinki, Finland ;3.STUK-Radiation and Nuclear Safety Authority, Laippatie 4, 00880, Helsinki, Finland ;4.European Commission, Joint Research Centre (JRC), Directorate G—Nuclear Safety and Security, Nuclear Safeguard and Forensics, P.O. Box 2340, 76125, Karlsruhe, Germany ; |