AN AUTOMATED 4-CRYSTAL SCINTILLATION SPECTROMETER FOR THE STUDY OF GAMMA-RADIATION ALBEDO

A four-crystal scintillation spectrometer is described. The spectromet er is intended for studying the angular distributions of bremsstrahlun g gamma-radiation leakage fluxes of an MT-22S microtron. Four 63-mm-di ameter and 63-mm-height NaI(Tl) crystals with phi EU-82 photomultiplie rs are used in the spectrometer to detect gamma-rays. Circuits for pul se selection provide detection of only one gamma-quantum in each of th e spectrometer channels during each electron-acceleration cycle. The s pectrometer permits simultaneous detection of gamma-radiation leakage fluxes at each of the four angles selected, with a count rate of about 400 quanta/s in the 0.05-3-MeV energy range, The spectrometer resolut ion is approximately 10-13% at a gamma-radiation energy of 0.511 MeV.