About possibility of measurement of single-photon spectra under condition of multiple photon generation

In this work, the possibility of different techniques to measure real spect ral-angular distributions of radiation under conditions of multiple photon generation is analyzed in dependence of experimental requirements, The tech nique based on Compton scattering, on narrow collimation of direct gamma-qu anta beams, on pair magnetic spectrometer use and on measured opening angle s of electron-positron pairs are examined. It is shown that for the measure ment of photon spectral-angular distributions and photon multiplicity one c all employ the narrow collimation technique. The real photon spectra within the limited emission angle may be measured with a pair magnetic spectromet er. An estimate of the multiplicity of the photons, which are registered by a total absorption spectrometer as one photos and the average energy of th ese photons may be obtained by measuring the opening angle of the electron- positron pairs generated by the photons in a thin converter. (C) 2001 Elsev ier Science B.V. All rights reserved.