Spectra and Dose Fractions of Monoenergetic Neutrons Passed Through Different Shields and Their Application for Dose-meter Evaluation

Leakage neutron spectra for monoenergetic sources and for slab shields of different compositions and thicknesses are calculated. Source energies ranging from 0.34 keV to 10.5 MeV are considered, for the following shield materials: water, concrete, boron-loaded polythene and iron, at thicknesses ranging from 5 to 60 cm. Corrections to readings of several dose-meters are determined, making use of the spectra. The measured percentages of the dose- equivalent are evaluated for the following devicesi thermal neutron detectors, the Harvey albedo dosemeter, Yoshida -Dennis proportional counter, Dennis - Loosemore counter, nuclear emulsion and proton-recoil scintillation coumter. Dose-meter reading calculations are extended up to 15 MeV energy, which is of great practical importance at neutron generator monitoring. Finally recommendations are given concerning the selection of dose-meters for different monoenergetic neutron sources wlth different shieldings. (auth)