On the nuclear emulsion detection efficiency for alpha particles and fission fragments

Abstract In this work, the efficiency (ϵ) of the Fuji ET2F nuclear emulsion loaded with samarium was determined, for the detection of α-particles with energies ⩾ 2 MeV. By performing measurements of the superficial track density in five different exposure times varying between 15 and 54 days, the result ϵ = 1.000 ± 0.022 was obtained. Practically the same result, 0.999 ± 0.021, was obtained for α-particles having energies higher than 4.2 MeV, in the case of K0 Ilford uranium loaded emulsions developed 1.359 and 2.273 days after the loading. Since the linear density of Ag grains is high in both emulsions, the result obtained for the ET2F can be extended to the K0 one. In this way, the final results for the efficiency of K0 Ilford and ET2F Fuji nuclear emulsions for α-particles having energies higher than 4.2 MeV, can be adopted as equal to 1.000 ± 0.015. By means of using an adequate development process, these results can be used in the case of fission fragments detection.