Neutron dosimetry by the spark counting of tracks in boron-doped film.
Thin cellulose nitrate films are doped with a boron compound. After thermal neutron irradiation, the films are etched in an aqueous solution of 10% NaOH, at 50 degrees C, for 1.5 hr, during which the 27 microns thick films are reduced to about 7 microns. The etch-pits caused by 10B(n, alpha)7Li reactions are punched twice at 600 V and then counted at 500 V. The ratio of the spark density to the thermal neutron fluence was found to be 1.0 X 10(-4) for a boron concentration of 1%. After due consideration of background counts, a thermal neutron dose of 0.3 mrem (3 X 10(-6) Sv) can be measured with this system.
D001895:Boron; D005373:Film Dosimetry / Q000295:instrumentation* / Q000379:methods; D009502:Neutrons
D001895:Boron