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Direct Interaction Neutrons from 14-Mev Inelastic Neutron Scattering

Description: Abstract: "Neutron nonelastic cross sections measured at different detector biases have been used to determine the cross sections for inelastically scattering 14 Mev neutrons into 9- to 14-Mev energy range. The cross section for producing these high energy neutrons, which may be attributed to direct interaction processes, is roughly 10% of the nonelastic cross section, for all elements. A comparison is made with data of Coon and co workers, who measured angular distributions for the same high-energy inelastically scattered-neutron group."
Date: May 19, 1958
Creator: MacGregor, Malcolm H.
Partner: UNT Libraries Government Documents Department

Evaluated Neutron Cross Sections for Tritium

Description: From foreword: Evaluation of the experimental data on the light isotopes, hydrogen through beryllium, was initiated by LASL in mid-1963. Since the data compilations available were completely inadequate for the task at hand, the tedious program of compiling and plotting was undertaken. As the work progressed an attempt was made to eliminate many of the obvious errors and inconsistencies found in the literature and existing compilations.
Date: February 1965
Creator: Stewart, Leona
Partner: UNT Libraries Government Documents Department

Technical Concept-Operation Henre

Description: From Introduction: "As a result of research accomplished during Operation BREN in 1962, it has been proposed that a monoenergetic point neutron source be constructed and operated on the same tower. The field experiment which would be conducted at this time has been designated as Operation HENRE (High Energy Neutron Reactions Experiment)."
Date: February 1965
Creator: Haywood, F. F. & Auxier, J. A.
Partner: UNT Libraries Government Documents Department

A Low Dead-Time Neutron-Counting-System

Description: From Abstract: "This report describes a counting system capable of processing input pulses at an average rate in excess of 3 x 10 to the fifth power counts per second with less than 10 percent counting loss due to instrumental dead time."
Date: January 1961
Creator: Epstein, Robert J. & Thompson, Donald C.
Partner: UNT Libraries Government Documents Department

Neutron Scattering Angular Distribution

Description: From Introduction: "The remainder of this report describes the experiment and analytical methods which were used to obtain corrected cross sections in the representation shown in the graphs."
Date: June 1956
Creator: Langsdorf, A, Jr.; Lane, R. O. & Monahan, J. E.
Partner: UNT Libraries Government Documents Department

Scintillation Spectrometer System for Measuring Fast-Neutron Spectra in Beam Geometry

Description: A high-energy liquid-organic scintillation spectrometer system is described. This spectrometer was developed to measure neutron spectra in extracted beams from zero-power fast reactors. The highly efficient NE-213 scintillation solution was used as the neutron detection medium. Identification and removal of gamma-ray-induced events was accomplished using electronic pulse shape discrimination. Instrumentation used to process the discrete pulses stemming from neutron and gamma-ray interactions, within the scintillation solution, is described in detail. Evaluation of the system's performance is discussed for a gamma-ray discrimination ratio of nominally 1000:1, a total count-rate of 3000 cps, and a dynamic range corresponding to neutron energies from 1 to 10 MeV. Operation above 10 MeV is certainly possible. However, since the neutron flux above 10 MeV was negligible in the radiation fields of interest in this work, the operating characteristics of the spectrometer were not evaluated above 10 MeV. Neutron spectra are reported for extracted beam measurements made on ZPPR assembly 4, phase 2.
Date: May 1977
Creator: Simons, G. G.; Larson, J. M. & Reynolds, R. S.
Partner: UNT Libraries Government Documents Department

Gamma Ray Response of a CsI(T1) Crystal to 14 Mev Neutrons

Description: The purpose of this paper is to study the possible excited states in the nucleus of Cs133. At North Texas State College a 100-Kev Cockcroft-Walton accelerator has been constructed for use as a neutron source for exciting various nuclei and for studying the gamma spectra obtained to determine their energy levels.
Date: August 1958
Creator: Young, Jack Carter
Partner: UNT Libraries

MUFT Revision : A Fast Neutron Spectrum Code for the IBM-650

Description: Report documenting the MUFT-R program, which is "designed to solve the fast neutron transport problem for general mixtures of elements and obtain sets of average fast neutron diffusion constants for specified portions of the fast energy spectrum" (p. iii). Includes detailed derivations of utilized equations.
Date: 1962
Creator: Grimesey, Robert A.; Mullin, Frank Edward & Gannon, L. J.
Partner: UNT Libraries Government Documents Department

The Investigation of Fundamental Interactions with Cold Neutrons

Description: Abstract: The National Bureau of Standards is establishing a National Cold Neutron Facility at its 20 MW reactor located in Gaithersburg, Maryland. In order to provide guidance in the development of research plans for the Facility, the Department of Energy and NBS sponsored, on November 14-15, 1985, a workshop on the Investigation of Fundamental Interactions with Cold Neutrons. The 25 papers presented at the workshop are printed in the proceedings.
Date: February 1986
Creator: Greene, G. L.
Partner: UNT Libraries Government Documents Department

The Bragg Reflection of Neutrons by a Single Crystal

Description: From cover page: This document has been assigned the above MDDC (Manhattan District Declassification) number, as given in the List of Declassified Documents issued semi-monthly by the Research Division, Manhattan District. In the case of Los Alapnos reports, LADC (Los Alamos Declassification) numbers are listed on the title page if known. This declassified document may differ materially from the original classified document by reason of deletions necessary to accomplish declassification. Hence, this copy of a declassified document does not constitute authority for declassification of classified copies of a similar document which may bear the same title and authors. Reference is made to District Circular Letter (Research Control 47-3) dated 31 October 1946, subject: "Instructions for Use of List of Declassified Documents," which outlines the procedure by means of which declassification of classified copies may be effected. Every effort has been made to reproduce with accuracy of detail the declassified document as certified for declassification. No corrections or changes have been made in the content of the document.
Date: June 14, 1946
Creator: Zinn, Walter H.
Partner: UNT Libraries Government Documents Department

MeV Total Neutron Cross Sections

Description: From Introduction: "This report is a compilation of the MeV Total Neutron Cross Section data measured at the U.S. National Bureau of Standards."
Date: January 1974
Creator: Schwartz, Robert B.; Schrack, Roald A. & Heaton, H. Thompson, Jr.
Partner: UNT Libraries Government Documents Department

The Diffusion Length and the Utilization of Thermal Neutrons in a Heterogeneous Pile

Description: Abstract: "An accurate calculation is given for the quantity which corresponds to the diffusion length in the theory of the pile. The procedure is to establish a relationship between the diffusion length and the change in thermal utilization from a pile with infinite sides to one with sides of a finite length. The calculation of this change in the thermal utilization is then carried through. Approximation to the answer and numerically exact calculations are given in the report. The results show that for radif very near the optimum values the exact diffusion length is slightly larger than the one obtained from the usual formula...However, over most of the range of radii the exact diffusion length is smaller than the approximate one."
Date: October 6, 1943
Creator: Plass, Gilbert N.
Partner: UNT Libraries Government Documents Department

Angular distribution of neutrons from a plane surface

Description: From introduction: "This report determines lattice losses by considering the angular distribution of the neutrons emitted from the interior faces of the lattice and the exterior faces of the target. The purpose of this report is to investigate this problem by considering the dimensions of the faces to be large compared to the total mean free path."
Date: 1951
Creator: Harker, Wesley H.
Partner: UNT Libraries Government Documents Department

Effect of Boron Liner on Neutron Background in Cavity

Description: Introduction: "In connection with conducting neutron experiments in a pit with earth and concrete walls, it was proposed that the background flux of neutrons might be reduced by lining the walls of the pit with a neutron absorber such as boron. To determine how much liner material would be desirable and what diminution in the neutron background could be expected, the following measurements were undertaken."
Date: January 16, 1953
Creator: Benveniste, Jack
Partner: UNT Libraries Government Documents Department

Effect of Epithermal Capture on η

Description: The purpose of this report is to investigate the effect of neutrons being captured before they are completely slowed down and have the chance to leak out and thus correspondingly increase the multiplication factor of the lattice.
Date: 1952
Creator: Cohen, E. Richard, 1922-
Partner: UNT Libraries Government Documents Department