Gamma-radiation characteristics of 1.2 GeV electrons in thick silicon single crystals

The disadvantages of the conventional technique for measuring gamma-radiati on spectra in thick single crystals under the multiple generation of gamma- quanta by a single electron are described. New data on characteristics of g amma-radiation generated by 1.2 GeV electrons in aligned silicon single cry stals with the thickness values 15, 30 and 63 mm are reported. We have obta ined them by applying the technique of measuring the spectra of gamma-quant a, enabling one to obtain "true" spectra free from distortions due to the m ultiple generation of gamma-quanta. The maximum spectral density of radiati on in the energy range omega congruent to 15-20 MeV is shown to be obtained for a silicon crystal 30 mm thick, this value being optimum for the condit ions given. (C) 2001 Elsevier Science B.V. All rights reserved.