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in creator/contributor: "Kelly, J.G."

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Transimssion and compression of an intense relativistic electron beam produced by a converging annular diode with return current feedback through the cathode. Part II. The experiments

The complete results of the experiments with the converging annular diode within return current feedback through the cathode (Triax) are reported herein. The diode was designed to focus a relativistic high-current electron beam to a small focus. It did confirm the Triaxial theory detailed in Part I, and it did achieve a factor of 10 areal compression with 50% efficiency (which was below expectations). There were two principal reasons for this shortfall. First, the rapid diode plasma motion of 1… more

Date: February 1, 1976

Creator: Kelly, J. G. & Schuch, R. L.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Coded aperture imaging of reactor illuminated LMFBR fuel pins

As a part of Sandia Laboratories program to study simulated core disruptive accidents in reactor safety research, a fuel motion detection system based on coded aperture imaging is being developed. Until the experiments reported here were conducted it was not known whether either of two important questions could be properly answered. First, could an actual fuel pin illuminated by a reactor be imaged with a coded aperture and an active detector system with acceptable frame rates and spatial resol… more

Date: January 1, 1977

Creator: Kelly, J. G. & Stalker, K. T.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Characterization of the SPR II generated radiation environments next to and within a guidance system

The neutron fluences and spectra and the gamma ray doses inside and in the vicinity of a guidance system exposed to the Sandia Pulsed Reactor II (SPR II) in four configurations have been determined. This project required customization of the environment and the application of new techniques to determine the spectra within the system. The required radiation environment was achieved, and the experimental results clearly demonstrated that the radiation environment inside the system was very differ… more

Date: February 1994

Creator: Kelly, J. G. & Griffin, P. J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Status of neutron dosimetry cross sections

Several new cross section libraries, such as ENDF/B-VI(release 2), IRDF-90,JEF-2.2, and JENDL-3 Dosimetry, have recently been made available to the dosimetry community. the Sandia National Laboratories (SNL) Radiation Metrology Laboratory (RML) has worked with these libraries since pre-release versions were available. this paper summarizes the results of the intercomparison and testing of dosimetry cross sections. As a result of this analysis, a compendium of the best dosimetry cross sections w… more

Date: December 31, 1992

Creator: Griffin, P. J. & Kelly, J. G.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Fast shutter for low background radiation environments at SPR III

A fast shutter system has been developed and used to isolate experiments from the radiation emitted after the main pulse of the Sandia Pulse Reactor, SPR 3. In about 15 ms the system moves a massive 20 kg shield in front of the beam port aperture in the facility shield wall. A second gravity-driven shutter is dropped into place in about 200 ms. The total attenuation achieved in the beam intensity is about a factor of one hundred. The shutter assembly was used, along with a sensitive detection s… more

Date: August 1, 1994

Creator: Kelly, J. G.; Sites, K. & Scott, W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Updated neutron spectrum characterization of SNL baseline reactor environments. Volume 2, Analysis computer listings

This document provides SAND-II and MANIPULATE output listings from calculations used to derive the new spectrum-averaged integral parameters that were reported in volume 1. When used in conjunction with volume 1, this document provides an audit trail for the neutron radiation field characterization and supports current quality assurance initiatives. This document provides detailed information on the neutron spectrum characteristics of the primary Sandia National Laboratories` (SNL) reactor envi… more

Date: April 1, 1994

Creator: Griffin, P. J.; Kelly, J. G. & Vehar, D. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Updated neutron spectrum characterization of SNL baseline reactor environments. Volume 1, Characterization

The neutron spectrum characteristics of the primary reactor environments are defined for use by facility customers and to provide an audit trail in support of current quality assurance initiatives. The neutron and gamma environments in the four primary customer environments at SPR-III and ACRR facilities are characterized in detail. Enough detail is provided on other frequently-used environments to support the definition of the 3-MeV and 1-MeV(Si) fluence provided on the Radiation Metrology Lab… more

Date: April 1, 1994

Creator: Griffin, P. J.; Kelly, J. G. & Vehar, D. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

User`s manual for SNL-SAND-II code

Sandia National Laboratories, in the process of characterizing the neutron environments at its reactor facilities, has developed an enhanced version of W. McElroy`s original SAND-II code. The enhanced input, output, and plotting interfaces make the code much easier to use. The basic physics and operation of the code remain unchanged. Important code enhancements include the interfaces to the latest ENDF/B-VI and IRDF-90 dosimetry-quality cross sections and the ability to use silicon displacement… more

Date: April 1, 1994

Creator: Griffin, P. J.; Kelly, J. G. & VanDenburg, J. W.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Benchmarking the Sandia Pulsed Reactor III cavity neutron spectrum for electronic parts calibration and testing

The SPR III bare cavity spectrum and integral parameters have been determined with 24 measured spectrum sensor responses and an independent, detailed, MCNP transport calculation. This environment qualifies as a benchmark field for electronic parts testing.

Date: August 1, 1993

Creator: Kelly, J. G.; Griffin, P. J. & Fan, W. C.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Theory and application of the coded aperture fuel motion detection system

A fuel motion detection system based on coded aperture imaging has been developed for the Annular Core Research Reactor. Its configuration evolved after investigations were carried out to determine the required system capabilities. The reactor environment, developments in the theory of coded apertures for nuclear radiations and compatibility with prototypical geometries were considered. The system was fabricated and inserted into the ACRR where it has recorded the fuel motion from a single pin … more

Date: January 1, 1979

Creator: Kelly, J.G.; Stalker, K.T.; McArthur, D.A.; Chu, K.W. & Powell, J.E.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

SNL RML recommended dosimetry cross section compendium

A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty … more

Date: November 1, 1993

Creator: Griffin, P. J.; Kelly, J. G.; Luera, T. F. & VanDenburg, J.

Item Type: Report

Partner: UNT Libraries Government Documents Department

open access

Characterization of reactor neutron environments at Sandia National Laboratories

To assure quality in the testing of electronic parts in neutron radiation environments, Sandia National Laboratories (SNL) has incorporated modern techniques and procedures, developed in the last two decades by the radiation effects community, into all of its experimental programs. Attention to the application of all of these methodologies, experiment designs, nuclear data, procedures and controls to the SNL radiation services has led to the much more accurate and reliable environment character… more

Date: August 1, 1994

Creator: Kelly, J. G.; Luera, T. F.; Griffin, P. J. & Vehar, D. W.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Factors affecting use of fission foils as dosimetry sensors

Fission foils are commonly used as dosimetry sensors. They play a very important role in neutron spectrum determinations. This paper provides a combination of experimental measurements and calculations to quantify the importance and synergy of several factors that affect the fission response of a dosimeter. Only when these effects are properly treated can fission dosimeters be used with sufficient fidelity.

Date: December 31, 1996

Creator: Griffin, P. J.; Vehar, D. W.; Kelly, J. G. & Holm, C. V.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Neutron dosimetry with the {sup 58}Ni(n,p){sup 58}Co reaction at short-decay times

The {sup 58}Ni(n,p){sup 58}Co reaction is a very attractive choice for use as shown a neutron fluence monitor foil in reactor irradiations. The most important drawback to this reaction is the interference from the 9.15-h half-life {sup 58m}Co metastable state. A methodology is presented in this paper to allow the {sup 58g}Co ground-state activity to be read at short decay times and to be converted into the total {sup 58t}Co activity with no significant increase in the measurement uncertainty. T… more

Date: December 31, 1992

Creator: Griffin, P. J.; Holm, C. V.; Vehar, D. W. & Kelly, J. G.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

An examination of the 1-MeV equivalent silicon damage methodology

The assumptions, approximations, and uncertainty in the 1-MeV equivalent silicon damage methodology are reviewed. A new silicon displacement kerma function, based on ENDF/B-VI cross sections, is presented and its shape is experimentally confirmed. The issue of an associated 1-MeV equivalent reference kerma value is discussed. 19 refs., 4 figs.

Date: January 1, 1990

Creator: Griffin, P. J.; Kelly, J. G.; Luera, T. F. & Lazo, M. S.

Item Type: Article

Partner: UNT Libraries Government Documents Department

open access

Interlaboratory verification of neutron spectra used for the testing of electronic parts

A methodology has been developed for verifying that a neutron energy spectrum measured for an environment correctly predicts the bulk displacement damage that would be observed in a silicon electronic device. The technique makes use of a package of silicon bipolar transistors (2N2222A), monitor activation foils (such as sulfur pellets), and thermoluminescence detectors (TLDs) that is placed in the test environment. The TLDs and monitors are then used to correct for the gamma-induced damage and … more

Date: December 31, 1992

Creator: Kelly, J. G.; Griffin, P. J.; Raupach, D. C.; Daubenspect, T. H.; Bennion, J. S. & Newell, D. L.

Item Type: Article

Partner: UNT Libraries Government Documents Department