Absolute Thermal Neutron Fluence Determination By Thin Film Of Natural Uranium

An absolute monitor of thermal neutron fluence based on the 235U induced fission was developed. This monitor is constituted by a solid state nuclear track detector juxtaposed to a natural uranium film with a negligible self-absorption to fission fragments. In order to perform the calibration of the films, the alpha-activity was measured by using nuclear emulsions. The preparation, calibration and employment procedures of this monitor are presented. © 1995.3523588591International Atomic Energy Agency, (1970) Neutron Fluence Measurements, Technical Reports Series No. 107, , ViennaFleischer, Price, Walker, (1975) Nuclear Tracks in Solids: Principles and Applications, , Univ. of California Press, BerkeleyHurford, (1990) Chem. Geol. (Isot. Geosci. Sect.), 80, p. 171Hurford, Green, (1983) Isot. Geosci., 1, p. 285Tagami, Nishimura, (1992) Chem. Geol. (isot. Geosci. Sect.), 102, p. 277Green, Hurford, (1984) Nucl. Tracks, 9, p. 231Gold, Armani, Roberts, (1968) Nucl. Sci. Eng., 34, p. 13Wall, (1986) Nucl. Tracks, 12, p. 887Ruddy, (1986) Nucl. Tracks Radiat. Meas., 11, p. 197Lederer, Shirley, (1978) Table of Isotopes, , 7th ed., Wiley, New YorkYagoda, (1949) Radioactive Measurements With Nuclear Emulsions, , Wiley, New YorkBigazzi, Hadler, Iunes, Osorio, (1991) Nucl. Tracks Radiat. Meas., 19, p. 451Hadler, (1979) Master Thesis, , Universidade Estadual de Campinas, Campinas, SP, BrazilJ.C. Hadler N., P.J. Iunes, T.C.W.P. Mello, L.M.S. Navia and S.R. Paulo, On The Nuclear Emulsion Detection Efficiency For Alpha Particles And Fission Fragments, to be submitted to Radiation MeasurementsIunes, (1990) Master Thesis, , Universidade Estadual de Campinas, Campinas, SP, BrazilWestcott, Effective Cross Section Values For Well-Moderated Thermal Reactor Spectra, Atomic Energy Of Canada Limited (1960) AECL Rep. 1101, , (3rd ed. corrected