Neutron and gamma-ray source-term characterization of AmBe sources in Osaka University

Abstract

Thermal / epi-thermal columns were constructed in the OKTAVIAN facility of Osaka University for basic studies of BNCT. For characterization of the columns, the spectrum and intensity of neutrons and the intensity of gamma-rays emitted from the AmBe sources used in the columns as a neutron source were measured. Neutrons were measured with the foil activation and multi-foil activation techniques, and gamma-rays were measured directly with an HpGe detector. The measured absolute intensity of neutrons is 2.4E6 n/sec. The measured neutron spectrum was fairly consistent with the previous result. The gamma-ray intensity was 1.8E6 photons/sec, which a little smaller than that of neutrons. The measured data are used for normalization of various experiments carried out for BNCT.