Development and actual tests of airborne gamma ray survey system

Airborne gamma ray survey system has been developed by IBRAE for radiation safety and emergency response tasks of EMERCOM. Basic design decisions of the system were verified during actual tests of constructed prototypes for manned and unmanned aircraft. For data processing tasks background modeling method, based on least squares fitting and pulse response function calculations, was developed. It uses count rates in several energy windows corresponding to photo peaks of natural radioactive nuclides and experimental assessments of terrestrial and spectrometer construction background. Application of this method may significantly increase sensitivity of the system and stability of results with relation to background variations. It is also possible to use it for radionuclide concentrations evaluation (for example Cs 137). Among many others appropriate function is included in designed program software.