About creation of phantoms for calibration of whole-body counting systems used in NPP

A module principle for creation of two phantoms is proposed. The modules have appropriate dimensions and densities allowing formation of human bodies with a weight 40 - 100 kg and a form close to real. The phantoms allow simulation of the homogeneous distributed activity as well as of the activity presented only in a critical organ. The zero phantom (without activity) is used for determining the background radiation of the detector at a chosen geometry of measurement. The modules of the other phantom will be homogeneously filled with reference activity of nuclides allowing determination of absolute efficiency of the semiconductor detector in range 60 keV till above 1400 keV. These phantoms are used for some typical geometries of measurement. Evaluation of the measurement error in a critical organ, using calibration of the homogeneously distributed in the whole body activity, is also done. (V.K.)