IBM 7094 program for calculation of fast neutron kinetics by Monte Carlo. Progress report, October, 1963

Progress report; October, 196

IBM 7094 program for calculation of fast neutron kinetics by Monte Carlo. Addendum no. 1, May 1964

Addendum no. 1; May 196

Spatial distribution of the neutron flux on the surface of a graphite-lined cavity

Statement of responsibility on title-page reads: J.T. Madell, T.J. Thompson, A.E. Profio, and I. Kaplan"April 1, 1962.""NYO-9657."Includes bibliographical references (leaves 315-316)U.S. Atomic Energy Commission contract AT(30-1)234

Measurements of the spatial and energy distribution of thermal neutrons in uranium, heavy water lattices

"August 20, 1962."Statement of responsibility on title-page reads: P. S. Brown, T. J. Thompson, I. Kaplan, A. E. ProfioAlso issued by the first author as a Ph. D. thesis, Massachusetts Institute of Technology, Dept. of Nuclear Engineering, 1962"NYO-10205."Includes bibliographical references (pages 185-210)Intracell activity distributions were measured in three natural uranium, heavy water lattices of 1. 010 inch diameter, aluminum clad rods on triangular spacings of 4. 5 inches, 5. 0 inches, and 5. 75 inches, respectively, and in a uranium, heavy water lattice of 0. 25 inch diameter, 1. 03% U 2235, aluminum-clad rods on a triangular spacing of 1. 25 inches. The distributions were measured with bare and cadmium-covered foils of gold, lutetium, and europium. The gold was used as a 1/v absorber to measure the thermal neutron density distribution. Because the activation cross sections of lutetium and europium depart considerably from 1/v behavior, their activation depends strongly on the thermal neutron energy spectrum. Hence, they were used to make integral measurements of the change in the neutron energy spectrum with position in the lattice cell. A method was developed for treating the partial absorption, by cadmium covers, of neutrons at the 0.46 ev europium resonance, and it was found possible to correct the europium activations to energy cutoffs just above and just below the resonance. The measured activity distributions were compared with those computed with the THERMOS code. In the natural uranium lattices, THERMOS gave excellent agreement with the measured gold activity distributions and very good agreement with the lutetium and europium distributions, indicating that THERMOS gives a very good estimate of the spatial and energy distribution of thermal neutrons in these lattices. In the enriched lattice, THERMOS gave a large overestimate of the activity dip in the fuel for all three detectors. The discrepancy was attributed to a breakdown in the Wigner-Seitz cylindrical cell approximation at small cell radii.However, the measured ratios of lutetium and europium activity to gold activity were in good agreement with the THERMOS values, indicating that THERMOS still gave a good estimate of the degree of spectral hardening. Neutron temperature calculations were made from the data by using Westcott effective cross sections. The temperature changes so calculated agreed well with those predicted by THERMOS. Disadvantage factors calculated by the Amouyal-Benoist-Horowitz (ABH) method were in excellent agreement with the measured values in the natural uranium lattices. The agreement was not as good in the enriched lattice because of an expected breakdown in the ABH method at small cell radii. Values of the thermal utilization obtained from experiment, from THERMOS, and with the ABH method were in excellent agreement for all the lattices studied.Radial and axial buckling measurements made with lutetium were in excellent agreement with similar measurements made with gold, indicating that the thermal neutron spectrum was uniform throughout the lattice tank. Measurements of intracell gold activity distributions made in off-center cells differed only slightly from those made in the central cell of the lattice, indicating that the radial flux distribution was almost completely separable into a macroscopic Jo and a microscopic cell distribution.U. S. Atomic Energy Commission contract AT(30-1)234

Studies of reactivity and related parameters in slightly enriched uranium, heavy water lattices

Statement of responsibility as it appears on title page reads: B. K. Malaviya, I. Kaplan, D. D. Lanning, A. E. Profio , T. J. Thompson"May 25, 1964."MIT-2344-1Includes bibliographical referencesU.S. Atomic Energy Commission contract AT(30-1)234

Heavy water, natural uranium research

NY0-10209Summary reportU.S. Atomic Energy Commission AT-30-1 234

Heavy water lattice project annual report / editors: Irving Kaplan, A.E. Profio [and] T.J. Thompson ; contributors P.S. Brown ... [et al.]

Statement of responsibility on title-page reads: editors: Irving Kaplan A.E. Profio, T.J. Thompson; contributors: P.S. Brown, W.H. D'Ardenne, J.Harrington, III, I.Kaplan, B.K. Malaviya, P.F. Palmedo, J.C. Peak. A.E. Profio. R. Simms. T.J. Thompson. A. Weitzberg. J,R. Wolberg"September 30, 1962""NYO-10, 208."Includes bibliographical referencesAnnual report; September 30, 1962U.S. Atomic Energy Commission contract AT(30-1)234

Heavy water lattice project annual report / editors: Irving Kaplan, D.D. Lanning, T.J. Thompson ; contributors H. E. Bliss ... [et al.]

Statement of responsibility on title-page reads: editors: Irving Kaplan, D.D.Lanning, T.J. Thompson; contributors: H. E. Bliss, F.M. Clikeman, W.H. D'Ardenne, J.W. Gosnell, J. Harrington, III, I.Kaplan, H. Kim, D.D. Lanning, B.E.Malaviya, E.E. Pilat, A.E. Profio, E. Sefchovich. R. Simms, T.J. Thompson, G.L. Woodruff"September 30, 1963"Includes bibliographical referencesAnnual report; September 30, 1963U.S. Atomic Energy Commission contract AT(30-1)234