Some applications of Ge(Li) gamma-ray spectroscopy to fuel element assay

"MIT-3944 -5."Also issued as a Ph. D. thesis by the first author and supervised by the second and third author, MIT Dept. of Nuclear Engineering, 1970Includes bibliographical references (pages 195-198)It was the object of this work to study the gamma rays emitted by the products of the interaction of thermal neutrons with the nuclei of U-238, Th-232, U-235 and Pu-239 during and after irradiation and to explore some applications mainly to fuel element assay. An irradiation facility and a Ge(Li) detector cryostat were constructed for this purpose. A new method of assaying a fuel rod containing a mixture of plutonium and uranium oxide, based on the difference in the observed yield of the fission products 1-135 and Sr-92, has been developed. The energies and intensities of the thermal neutron capture gamma rays for U-238 and Th-232 were determined. Four new lines have been found in the energy region previously unexplored for U-238. For Th-232, 66 certain lines were found, compared to 7 lines in the literature. Many prompt gammas emitted 'by the highly excited fission products following the fission of U-235 and Pu-239 were resolved in the energy region above 1.4 MeV. For U-235 fissions, 57 lines were found, and for Pu-239, 51 certain lines were recorded. The use of prompt gammas for assaying fuel rods was investigated. An accuracy of about ± 7% was obtained for the analysis of U-238 content; ± 10% to ± 20% accuracy was obtained for U-235 analysis in the range of 1% to 2% enrichment; and ± 35% accuracy for the analysis of 0.25% Puenriched rods. It has been found that Ge(Li) detectors can be operated as fast neutron detectors and used to determine the relative neutron yield. With this method, the enrichment of uranium rods can be found with an accuracy of ± 1% to ± 2% in the range from 116 to 2% enrichment. Finally, some considerations were given to the use of prompt gamma rays for measuring the initial conversion ratio C and the neutron yield parameter [eta].U.S. Atomic Energy Commission contract AT(30-1)-394

Thermal neutron capture gamma-ray spectra of the elements

"January 1969."Statement of responsibility on title-page reads: Norman C. Rasmussen, Yoshiyuti Hukai, Tamon Inouye, Victor J. Orphan"Prepared for Air Force Cambridge Research Laboratories, Office of Aerospace Research, United States Air Force, Bedford, Mass.""AFCRL-69-0071."Includes bibliographical referencesAF19(628)5551Project no. 5620, Task no. 562003, Work unit no. 5620030

Reactor physics project final report

"September 30, 1970."Statement of responsibility on title-page reads: Editors, M. J. Driscoll, I. Kaplan, D. D. Lanning, N. C. Rasmussen. Contributors: V. K. Agarwala, F. M. Clikeman, M. J. Driscoll, Y. Hukai, L. L. Izzo, I. Kaplan, M. S. Kazimi, D.D. Lanning, T.C. Leung, E.L. McFarland, N.C. Rasmussen, S.S. Seth, G.E. Sullivan, and A.T. SuppleIncludes bibliographical referencesFinal report; January 1, 1968 to September 30, 1970This is the final report in an experimental and theoretical program to develop and apply single- and few-element methods for the determination of reactor lattice parameters. The period covered by the report is January 1, 1968 through September 30, 1970. In addition to summarizing results for the entire contract period, this report also serves as the final annual report; thus, work completed in the period of October 1, 1969 through September 30, 1970 is dealt with in more detail than the earlier work. Methods were developed to measure the heterogeneous parameters 17, [Gamma] [eta] and [Alpha] for single fuel elements immersed in moderator in an exponential tank using foil activation measurements external to the fuel. These methods were applied to clustered fuel rods in D 20 moderator and single fuel rods in H 20 moderator, and the results were extended to and compared with data on complete multi-element lattices reported by other laboratories. Advanced gamma spectrometric methods using Ge(Li) detectors were applied to the analysis of both prompt and fission product decay gammas for the nondestructive analysis of the fuel used in this work. The latter includes both simulated burned fuel containing plutonium and actual burned fuel irradiated to 20,000 MWD/T in the Dresden BWR.U.S. Atomic Energy Commission contract AT (30-1)-394

Reactor physics project progress report

Statement of responsibility on title page reads: Editors: M.J. Driscoll and T.J. Thompson; Contributors: F.M. Clikeman, J.N. Donohew, M.J. Driscoll, J.D. Eckard, T.L. Harper, Y. Hukai, I. Kaplan, C.H. Kim, Y.-M. Lefevre, T.C. Leung, N.R. Ortiz, N.C. Rasmussen, C.S. Rim, S.S. Seth, A.T. Supple C. Takahata, and T.J. Thompson"MIT-3944-1."Progress report; September 30, 1968U.S. Atomic Energy Commission contract AT(30-1)-394

Reactor physics project progress report no. 2

Statement of responsibility on title page reads: Editors: M.J. Driscoll, I. Kaplan, D.D. Lanning; Contributors: V. Agarwala, F.M. Clikeman, J.N. Donohew, M.J. Driscoll, G. T. Hamilton, T.L. Harper, Y. Hukai, I. Kaplan, T. J. Kelley, D.D. Lanning, T.C. Leung, E.L. McFarland, N.C. Rasmussen, S.S. Seth, J.M. Sicilian, G.E. Sullivan, A.T.Supple and T.J. Thompson"September 30, 1969.""MIT-3944-4."Includes bibliographical referencesProgress report no. 2; October 1, 1968 through September 30. 1969This is the second annual report in an experimental and theoretical program to develop and apply single and few element heterogeneous methods for the determination of reactor lattice parameters. During the period covered by the report, October 1, 1968 through September 30. 1969, work was primarily devoted to measurement of the heterogeneous fuel element parameters (F, rl and A) of 19- and 31- rod clusters of plutonium-containing fuel. Methods development research focused on determination of the epithermal absorption constant, A. Calculations and an analysis of data reported in the literature were made to assess the applicability of heterogeneous methods to H 20- moderated systems. Advanced gamma spectrometric methods using Ge(Li) detectors were applied to the analysis of prompt and delayed gamma spectra from fertile and fissile materials and from fuel elements. These methods were used successfully for nondestructive analysis of the composition of fuel elements. A feasibility study was performed on an in-pile gamma spectrometer. Two fuel pins irradiated to a burnup of approximately 20,000 MWD/MT in the Dresden reactor were received and preparations made for their analysis and use in reactor physics experiments.U. S. Atomic Energy Commission contract AT(30-1)-394