A HIGHLY EFFICIENT ALPHA-SPECTROMETER, BETA-SPECTROMETER, GAMMA-SPECTROMETER WITH LOW-BACKGROUND

A highly efficient low-background spectrometer based on phoswich detec tor design and characteristics are described. The spectrometer allows measurements in a broad energy range of alpha-, beta- and gamma-radiat ion emitted from the natural radionuclides to be carried out. The phos wich detector consists of a fast scintillator based on the doped p-ter phenyl single crystal and a slow CWO scintillator. Separate detection of each type of radiation is made possible by means of signal discrimi nation over the pulse shape. The minimum detectable activity of Sr-90 + Y-99 equal to 1 Bq was achieved. Advantages of the proposed spectrom eter are discussed, and quantitative data on the minimum detectable ac tivities for each type of radiation are presented.