Measurement of neutron capture cross-section of indium in the energy region from 0.003 eV to 30 keV

Abstract

The neutron capture cross-section of indium (In) has been measured in the energy region from 0.003 eV to 30 keV by the neutron time-of-flight (TOF) method with a 46-MeV electron linear accelerator (linac) of the Research Reactor Institute, Kyoto University. An assembly of Bi 4Ge 3O 12 (BGO) scintillators, which was composed of 12 pieces of BGO and placed at a distance of 12.7±0.02 m from the neutron source, was employed as a total energy absorption detector for the prompt capture γ-ray measurement from the sample. In order to determine the neutron flux impinging on the capture sample, a plug of 10B powder sample and the 10B(n,α) standard cross-section were used. The data measured by Haddad et al. (Haddad, E., Friesenhahn, S., Lopez, W.M., 1963. Report of Gulf Energy and Environmental Systems, p. 3874) seem to be in good agreement with the present measurement. Popov et al. obtained the poor energy resolution data in the resonance region with a lead slowing-down spectrometer and the consistent data with the present above about 300 eV. The experimental data measured by Kononov et al. (Kononov, U.N., Jurlov, B.D., Poletaev, E.D., Timokhov, V.M., Manturov, G.N., 1977. Report of Obninsk, pp. 22–29) and Gibbons et al. (Gibbons, J.H., Macklin, R.L., Miller, P.D., Neiler, J.H., 1961. Phys. Rev. 122, 182) showed good agreement with the present values in the higher energy region. However, the data measured by Block et al. (Block R.C., Kaushal, N.N., Hockenbury, R.W., 1972. Conference on New Developments in Reactor Physics and Shielding at Kiamesha Lake, Vol. 2, p. 1107) seem to be a little higher than the present measurement above 800 eV. The evaluated data in ENDF/B-VI, JENDL-3.2, and JEF-2.2 have been in general agreement with the present result in the relevant energy region, although the JENDL-3.2 are higher than the measurement, the ENDF/B-VI and the JEF-2.2 from 2 to about 10 keV. Most of the previous experimental and the evaluated thermal neutron cross-sections are generally close to the present value of 199.6±5.6 b at 0.0253 eV.