GAMMA-SPECTROMETRY METHOD FOR DETERMINING AMOUNT OF RADIOACTIVE NUCLIDES

摘要

FIELD: technology for determining amount of radioactive nuclides in thin-walled objects.;SUBSTANCE: gamma-spectrometry method for determining amount of radioactive nuclides, evenly distributed in object, includes calibration of gamma-spectrometer with collimated detector using standard and three measurements of count speed of gamma-quanta: from object being examined, from object being examined and additional source positioned behind it, and from additional source only. As standard for calibration, flat standard is used with given surface activity of radioactive nuclide. During calibration, detector is mounted at distance from standard, at which section of aperture of detector by plane of standard does not transcend active spot of standard, and during measurements of count speeds detector is mounted at such a distance from object being examined, so that figure, formed by intersection of aperture of detector and object being examined has shape of truncated circular cone. On basis of measured count speeds of gamma-quanta coefficient of linear weakening of object radiation is determined, and amount of radioactive nuclides in object being examined is determined mathematically.;EFFECT: possible measurements in objects with low activity of gamma radiation, using regular standard sources.;5 dwg