[22p-F307-1~11] 2.2 Radiation physics fundamentals & applications, radiation generators, new technology

△ [22p-F307-4] Evaluation of Self-Shielding Factors for Self-activation Method using a CsI scintillator

〇Masakazu Horiuchi¹, Genichiro Wakabayashi¹, Akihiro Nohtomi², Nayuta Nagatomo¹, Riku Mastumura¹ (1.Kindai Univ., 2.Kyusyu Univ.)

Keywords:CsI scintillator, thermal neutron, activation method

Low neutron fluxes can be measured with high accuracy by the self-activation method using a CsI scintillator in a short irradiation time. However, as the volume of the CsI scintillator as a target material is larger than that of the conventional activation method, the effect of self-shielding is larger, and the neutron flux in the scintillator is largely attenuated. Therefore, the result obtained by the self-activation method needs to be corrected with a self-shielding factor. In this study, a self-shielding factor was calculated for the thermal neutron flux measurement in a thermal reactor, and the measured thermal neutron flux were corrected by the self-shielding factor.