Abstract: This paper presents the prototype of portable radionuclide identification system developed by the Institute of Nuclear Physics and Chemistry of China Academy of Engineering Physics. This portable radionuclide identification system which is a gamma ray spectrometer using a LaBr₃(Ce) detector and a pulse height multi-analyzer, can be applied in radionuclide detection, dosimetry, radioactive source searching and environmental radiation inspection. With this system, if any exceptional radioactivity was reported in the outflow from a nuclear power plant or nuclear material manufacturer, the type of radionuclides and the radioactivity as well can be identified and evaluated efficiently and precisely at the outflow securing the radiation safety to the operating staffs.

Key words: LaBr₃(Ce) crystal, nuclide detection, energy resolution