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The multipulse Thomson scattering diagnostic on the DIII-D tokamak

Description: This paper describes the design and operation of a 40-spatial channel Thomson scattering system that uses multiple 20 Hz Nd:YAG lasers to measure the electron temperature and density profiles periodically throughout an entire plasma discharge. Interference filter polychromators disperse the scattered light which is detected by silicon avalanche photodiodes. The measurable temperature range from 10 eV to 20 keV and the minimum detectable density is about 2 {times} 10{sup 18} m{sup {minus}3}. Las… more
Date: September 1, 1991
Creator: Carlstrom, T. N.; Campbell, G. L.; DeBoo, J. C.; Evanko, R. G.; Evans, J.; Greenfield, C. M. et al.
Partner: UNT Libraries Government Documents Department
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Magnetic field, closed orbit, and energy measurement in the Bevatron

Description: This report provides the information necessary for a better evaluation of particle energy in the Bevatron. Previously, the nominal magnetic field value and radius were used to calculate the value for the kinetic energy of the particle. This value was good to a few percent. Today, more and more experimenters would like to know the energy to a more precise value. To this end, corrections to the measured magnetic field values and the radial closed orbit are provided.
Date: November 1, 1981
Creator: Crebbin, K. C.
Partner: UNT Libraries Government Documents Department
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Search for the neutrinoless muon decay. mu. /sup +/. -->. e/sup +/. gamma

Description: Separate muon, electron, and tau numbers are conserved in the minimal standard model of electroweak interactions with massless neutrinos. However, in many extensions to the standard model, separate lepton numbers are not expected to be conserved quantities. A new search for muon number non-conserving processes has been undertaken at the Los Alamos Meson Physics Facility (LAMPF), specifically to look for three neutrinoless decay modes of the muon. The search for the decay of a muon to an electro… more
Date: July 1, 1985
Creator: Wilson, S.L.
Partner: UNT Libraries Government Documents Department
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Establishment of viscometer capability for geopressured fluids. Project 61024 final report, November 19, 1978-December 31, 1979

Description: The feasibility of modifying the IGT capillary viscometer for the measurement of methane-saturated brines at 10,000 psi and 200/sup 0/C was evaluated. The viscometer was cleaned, modified, reassembled and pressure treated. The density cells were calibrated to a precision of approximately 7%. The viscosity of pure value was measured and the best value obtained was 6% below values reported in the literature. The operation of the viscometer was time-consuming and required meticulous cleaning betwe… more
Date: October 1, 1980
Creator: Rockar, E. & Randolph, P.
Partner: UNT Libraries Government Documents Department
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Aspects of model selection in multivariate analyses

Description: Analysis of data sets that involve large numbers of variables usually entails some type of model fitting and data reduction. In regression problems, a fitted model that is obtained by a selection process can be difficult to evaluate because of optimism induced by the choice mechanism. Problems in areas such as discriminant analysis, calibration, and the like often lead to similar difficulties. The preceeding sections reviewed some of the general ideas behind assessment of regression-type predic… more
Date: January 1, 1982
Creator: Picard, R.
Partner: UNT Libraries Government Documents Department
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The collaborative program of research in engineering sciences

Description: Research programs in the following areas are briefly described: High-Temperature Gas-Particle Reactions; Mathematical Modelling of Plasma Systems; Metal Transfer in Gas Metal-Arc Welding; Multivariable Control of Gas Metal-Arc Welding; Synthesis of Heat and Work Integration Systems for Chemical Process Plants; Parity Simulation of Dynamic Processes; Fundamentals of Elastic-Plastic Fracture: Three-Dimensional and Mechanistic Modelling; and Comminution of Energy Materials. Publications from each … more
Date: August 1, 1989
Creator: White, D.C.
Partner: UNT Libraries Government Documents Department
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X-ray, soft x-ray, and vuv beam position monitor

Description: An x-ray beam position monitor has been developed and is currently operational at the NIST beamline X-24A of the National Synchrotron Light Source, Upton, NY. It was developed to accurately measure the vertical position of the synchrotron beam and to allow precise positioning of beamline optics. It is an area type monitor positioned 5.6 meters from the Tangent Point and precedes all beamline instrumentation. Vertical beam position is given by the differential photoemission current from two grid… more
Date: January 1, 1991
Creator: Karlin, B.A. (Brookhaven National Lab., Upton, NY (United States)); Cowan, P.L. (Argonne National Lab., IL (United States)) & Woicik, J.C. (National Inst. of Standards and Technology (IMSE), Gaithersburg, MD (United States))
Partner: UNT Libraries Government Documents Department
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Introduction to albedo neutron dosimeters

Description: The design, operation, calibration, and performance of albedo neutron dosimeters are discussed. An albedo neutron dosimeter is designed to measure the flux of thermal neutrons which leave the body when a person is exposed to fast energy neutrons. The fast neutrons are scattered and moderated in the body, and many have lost most of their initial energy and emerge as thermal neutrons. The albedo neutron dosimeter is designed to detect this flux of thermal neutrons by using a thermal neutron detec… more
Date: January 16, 1978
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
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The electronics and data acquisition system for the Wire Imaging Synchrotron Radiation Detector at the SLC (Stanford Linear Collider)

Description: The Stanford Linear Collider (SLC) located at the Stanford Linear Accelerator Center collides electrons and positrons produced in the linear accelerator pulse by pulse. We determine the energy of each beam by measuring the angle of deflection of the beam in the SLC extraction lines. Each extraction line consists of two bending magnets that produce synchrotron radiation, and a spectrometer analyzing magnet that deflects the beam. We detect the synchrotron light by using the emission of electrons… more
Date: January 1, 1990
Creator: Rouse, F.; Briggs, D.D. (Stanford Linear Accelerator Center, Menlo Park, CA (USA)); Gomez, J.J.; Von Zanthier, C. & Kent, J. (California Univ., Santa Cruz, CA (USA))
Partner: UNT Libraries Government Documents Department
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Experimental considerations for the calibration of personnel dosimeters with photons

Description: The criteria for irradiating radiation dosimeters for test purposes are defined quite clearly in Draft ANSI Standard N13.11. In this Draft the use of phantoms, constructed of a near tissue equivalent material, is prescribed for backing the dosimeters while being irradiated, thus simulating a dosimeter being irradiated while attached to a person. When the phantom is placed in the photon beam it becomes a major source of scattered radiation. The scatter component into the dosimeter is a function … more
Date: unknown
Creator: Hooker, C.D.; Yoder, R.C. & Courtney, J.W.
Partner: UNT Libraries Government Documents Department
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New technique to improve the accuracy of albedo neutron dosimeter evaluations

Description: The calibration factor for albedo neutron dosimeters varies greatly depending upon the energy of the neutrons in the exposure. Calibration results obtained over an eight-year period at each Lawrence Livermore National Laboratory facility where neutron exposure may occur were reviewed. A stronger relationship than expected was found between the ratio of the readings of the 9-in. to 3-in. spheres and the percent thermal. Readings from personnel and albedo badges were reviewed. The readings were c… more
Date: January 1, 1984
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
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Radiation standards and calibrations. FY-1981 annual report

Description: The research program encompasses: reviewing calibration standards, regulations, and handbooks; assuring that calibration procedures used are in agreement with technically accepted methods; maintaining basic radioactive sources and instruments that serve as radiological standards; and providing traceability to the National Bureau of Standards where possible. In addition, major efforts are being expended to upgrade the 318 calibration facility. This report focuses on major accomplishments during … more
Date: July 1, 1982
Creator: Roberson, P. L.; Yoder, R. C.; Fox, R. A.; Hooker, C. D.; Hogan, R. T.; Holbrook, K. L. et al.
Partner: UNT Libraries Government Documents Department
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Evaluation of the neutron dose received by personnel at the LLNL

Description: This report was prepared to document the techniques being used to evaluate the neutron exposures received by personnel at the LLNL. Two types of evaluations are discussed covering the use of the routine personnel dosimeter and of the albedo neutron dosimeter. Included in the report are field survey results which were used to determine the calibration factors being applied to the dosimeter readings. Calibration procedures are discussed and recommendations are made on calibration and evaluation p… more
Date: May 1, 1982
Creator: Hankins, D.E.
Partner: UNT Libraries Government Documents Department
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Isotopic distributions, element ratios, and element mass fractions from enrichment-meter-type gamma-ray measurements of MOX

Description: The gamma-ray spectra from infinitely'' thick mixed oxide samples have been measured. The plutonium isotopics, the U/Pu ratio, the high-Z mass fractions (assuming only plutonium, uranium, and americium), and the low-Z mass fraction (assuming the matrix is only oxygen) can be determined by carefully analyzing the data. The results agree well with the chemical determination of these parameters. 8 refs., 3 figs., 3 tabs.
Date: January 1, 1991
Creator: Close, D. A.; Parker, J. L.; Haycock, D. L. & Dragnev, T.
Partner: UNT Libraries Government Documents Department
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Lead-Glass Wall addition to the Spear Mark I Magnetic Detector

Description: A ''Lead-Glass Wall,'' consisting of 318 lead-glass Cherenkov shower counters and three wire spark chambers, has been added to one octant of the SPEAR Mark I Magnetic Detector. The wall covers a solid angle of approximately 6 percent of 4..pi.. steradians and has been used to identify and measure the energies of electrons and photons produced in electron-positron collisions. The design, calibration, gain-monitoring, and performance of the system are described.
Date: October 1, 1977
Creator: Feller, J. M.; Barbaro-Galtieri, A. & Dorfan, J. M.
Partner: UNT Libraries Government Documents Department
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Time-Resolved Doubly Bent Crystal X-Ray Spectrometer

Description: X-ray spectroscopy is an essential tool in high temperature plasma research. We describe a time-resolved x-ray spectrometer suitable for measuring spectra in harsh environments common to many very high energy density laboratory plasma sources. The spectrometer consisted of a doubly curved Si(111) crystal diffraction element, a WL-1201 (ZnO:Ga) phosphor, a coherent fiber optic array, and two visible streak cameras. The spectrometer design described here has a minimum time resolution of 1.3 ns wi… more
Date: January 1, 1988
Creator: Hockaday, M. P.; Wilke, M. D.; Blake, R. L.; Vaninetti, J.; Gray, N. T. & Nedrow, P. T.
Partner: UNT Libraries Government Documents Department
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Physics at hadron colliders: Experimental view

Description: The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.
Date: August 1, 1987
Creator: Siegrist, J.L.
Partner: UNT Libraries Government Documents Department
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Robotic sample preparation for radiochemical plutonium and americium analyses

Description: A Zymate robotic system has been assembled and programmed to prepare samples for plutonium and americium analyses by radioactivity counting. The system performs two procedures: a simple dilution procedure and a TTA (xylene) extraction of plutonium. To perform the procedures, the robotic system executes 11 unit operations such as weighing, pipetting, mixing, etc. Approximately 150 programs, which require 64 kilobytes of memory, control the system. The system is now being tested with high-purity … more
Date: January 1, 1985
Creator: Stalnaker, N.; Beugelsdijk, T.; Thurston, A. & Quintana, J.
Partner: UNT Libraries Government Documents Department
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Multivariate calibration applied to the quantitative analysis of infrared spectra

Description: Multivariate calibration methods are very useful for improving the precision, accuracy, and reliability of quantitative spectral analyses. Spectroscopists can more effectively use these sophisticated statistical tools if they have a qualitative understanding of the techniques involved. A qualitative picture of the factor analysis multivariate calibration methods of partial least squares (PLS) and principal component regression (PCR) is presented using infrared calibrations based upon spectra of… more
Date: January 1, 1991
Creator: Haaland, D. M.
Partner: UNT Libraries Government Documents Department
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Calibration of a Hopkinson bar with a transfer standard

Description: During the past year, program field test temperatures, that are beyond the test accelerometer operational limits of {minus}30{degrees}F and +150{degrees}F, required the calibration of accelerometers at high shock levels and at the temperature extremes of {minus}50{degrees}F and +160{degrees}F. The purposes of these calibrations were to insure the accelerometers operated at the field test temperatures and to provide an accelerometer sensitivity at each test temperature. Since there is no NIST-tr… more
Date: January 1, 1991
Creator: Bateman, V. I.; Leisher, W. B.; Brown, F. A. & Davie, N. T.
Partner: UNT Libraries Government Documents Department
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Calculated thickness of tungsten alloy required for specified attenuation of gamma radiation from sup 137 CS

Description: The traditional method of evaluating and calibrating health physics instruments is to use a calibrator that consists of a single high-activity gamma radiation source with different attenuators to select the radiation level desired for tesing. To have accurate radiation intensities inside the calibrator cavity, the attenuators must be designed from precise absorption calculations. This paper reports calculations made to determine the thickness of tungsten alloy metal required for specific attenu… more
Date: January 1, 1991
Creator: Chiles, M. M.; Allin, G. W. & Pace, J. V. III
Partner: UNT Libraries Government Documents Department
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1991 Yearly calibration of Pacific Northwest Laboratory's gross gamma-ray borehole geophysical logging system

Description: This report describes the 1991 yearly calibration of a gross gamma-ray geophysical pulse logging system owned by the US Department of Energy (DOE) and operated by the Pacific Northwest Laboratory. The calibration was conducted to permit the continued use of this system for geologic and hydrologic studies associated with remedial investigations at the Hanford Site. Primary calibrations to equivalent uranium units were conducted in DOE borehole model standards that reside on the Hanford Site. The… more
Date: August 1, 1991
Creator: Arthur, R.J.
Partner: UNT Libraries Government Documents Department
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