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Measurement of the Slow Neutron Absorption Cross Section of Some Heavy Isotopes

Description: The following report investigates cross sections for the absorption of slow neutrons of heavy isotopes. The purpose of these measurements was to determine the cross section of an isotope of element 94 for the process of fission by the absorption of a slow neutron, relative to the cross section of U235 for the same process, that is, to measure R.
Date: 1943
Creator: English, Spofford Grady
Partner: UNT Libraries Government Documents Department

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

Notes on Predicted Fast Neutron Dose from Thermal Neutron Data in Water

Description: Abstract: "An appropriate method has been applied to predict fast neutron dosimeter data from thermal neutron measurements. Results are compared with actual dosimeter data and it is concluded that the method presented gives a good approximation for fast neutron dose. This is important since in many previous experiments fast neutron dosimeter data had not been taken, but thermal neutron data had been obtained."
Date: 1953
Creator: Stone, Henry E.
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

Neutrons from High Current Gaseous Discharges

Description: Abstract: "Experiments on the neutrons produced in a high-current pulse discharge in deuterium are described. With 15 kv applied to a straight discharge tube 30 cm in length neutrons are produced at ~1.4 [mu]sec after gas break-down in a pulse 0.1 [mu]sec in length. The yield, 10-7 - 10-8 neutrons per discharge, is quite sensitive to gas purity and discharge tube wall material. The axial asymmetry in neutron energy indicates that the neutrons were produced in reactions whose center of mass moves preferentially towards the cathode. Several mechanisms for the production of these neutrons are discussed."
Date: 1957
Creator: Dunaway, Robert 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 Effects of Internal Conversion on Critical Mass and Operating Life of a Thermal Reactor

Description: "This report was prepared for preliminary use only in the course of work under W31-109 Eng. 52, and the information contained herein may not be correct or in agreement with more recent experimental and operating data. Any values or opinions expressed in the report may only be those of the author, and the General Electric Company makes no representation or warranty (1) as to the value of this report for any purpose or (2) that any use of the report will not infringe the rights of others."
Date: July 21, 1952
Creator: Snyder, T. M.
Partner: UNT Libraries Government Documents Department