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Hazards control progress report No. 58, April-September 1979

Description: Progress is reported on research in the areas of radiation protection and industrial hygiene. Subject areas include: (1) basic computer programs for counting room automation; (2) a computing portable neutron spectrometer; (3) preliminary measurements of the neutron energy response of CR-39 carbonate plastic; (4) effect of high-expansion foam on self-1 contained breathing apparatuses; (5) permeation of organic solvents through glove samples; (6) determining neutron dose rates and 9-to-3 in. sphe… more
Date: February 22, 1980
Creator: Griffith, R.V. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Measurement of the relaxation time of hot electrons in laser-solid interaction at relativistic laser intensities

Description: The authors have measured the relaxation time of hot electrons in short pulse laser-solid interactions using a picosecond time-resolved x-ray spectrometer and a time-integrated electron spectrometer. Employing laser intensities of 10{sup 17}, 10{sup 18}, and 10{sup 19} W/cm{sup 2}, they find increased laser coupling to hot electrons as the laser intensity becomes relativistic and thermalization of hot electrons at timescales on the order of 10 ps at all laser intensities. They propose a simple … more
Date: August 22, 2006
Creator: Chen, H; Shepherd, R; Chung, H K; Dyer, G; Faenov, A; Fournier, K B et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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New Results From the LASS (Large Aperture Superconducting Solenoid) Spectrometer

Description: New results are presented from analyses of several mesonic and baryonic states containing one or more strange quarks. The data are taken from a high statistics (4 events/nb) study of K p interactions at 11 GeV/c carried out in the LASS Spectrometer at SLAC. New information is reported on the underlying K* states and also evidence for selective coupling of K eta to the K*'s; on the strangeonium members of the axial vector nonets in the K anti K channel; and on evidence for an * state.
Date: June 22, 1987
Creator: Aston, D.; Awaji, N.; Bienz, T.; Bird, F.; D'Amore, J.; Dunwoodie, W. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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PILAC: A pion linac facility for 1-GeV pion physics at LAMPF

Description: A design study for a Pion Linac (PILAC) at LAMPF is under way at Los Alamos. We present here a reference design for a system of pion source, linac, and high-resolution beam line and spectrometer that will provide 10{sup 9} pions per second on target and 200-keV resolution for the ({pi}{sup +}, K{sup +}) reaction at 0.92 GeV. A general-purpose beam line that delivers both positive and negative pions in the energy range 0.4-1.1 GeV is included, thus opening up the possibility of a broad experimen… more
Date: November 22, 1991
Creator: Thiessen, H.A. & White, D.H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Formation and evaluation of convex-curved crystals of lithium fluoride for use in analyzing x-ray spectra

Description: Lithium fluoride as received from the vendor in boule form is 38 x 38 x 13 mm thick. This block is cleaved to wafers of the desired thickness, x-ray-evaluated for ''d'' spacing and greatest intensity, bent to the required radius, and then acid-etched to remove foreign material. The diffraction and dispersion characteristics of a wafer are analyzed using well-collimated tungsten x rays that strike the crystal and are diffracted onto no-screen x-ray film. If the crystal is satisfactory, it is mou… more
Date: July 22, 1976
Creator: Sellick, Barton O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High spectral resolution measurements for the ARM Program

Description: This report focuses on the design and fabrication of high spectral resolution FTIR (Fourier Transform Infrared) instrumentation for the CART sites of the Atmospheric Radiation Measurement (ARM) Program. The ultimate objective of this grant is to develop three different types of instruments, named the AERI, AERI-X, and SORT. The Atmospheric Emitted Radiance Interferometer (AERI) is the simplest. It will be available for early deployment at the first ARM site and will be deployable at several loc… more
Date: May 22, 1992
Creator: Revercomb, H. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Single Cell Chromatography, LDRD Feasibility Study

Description: A limitation in the mass spectrometry of biological materials is the reduced ion formation caused by sample complexity. We proposed to develop an enabling technology, single cell planar chromatography, which will greatly increase the amount of chemical information that can be obtained from single biological cells when using imaging mass spectrometry or other surface analysis methods. The sample preparation methods were developed for the time-of-flight secondary mass spectrometer (ToF-SIMS) at L… more
Date: February 22, 2007
Creator: Knize, M G & Bailey, C G
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Reaction of the C2H radical with 1-butyne (C4H6): Low Temperature Kinetics and Isomer-Specific Product Detection

Description: The rate coefficient for the reaction of the ethynyl radical (C{sub 2}H) with 1-butyne (H-C{triple_bond}C-CH{sub 2}-CH{sub 3}) is measured in a pulsed Laval nozzle apparatus. Ethynyl radicals are formed by laser photolysis of acetylene (C{sub 2}H{sub 2}) at 193 nm and detected via chemiluminescence (C{sub 2}H + O{sub 2} {yields} CH (A{sup 2}{Delta}) + CO{sub 2}). The rate coefficients are measured over the temperature range of 74-295 K. The C{sub 2}H + 1-butyne reaction exhibits no barrier and … more
Date: December 22, 2009
Creator: Soorkia, Satchin; Trevitt, Adam J.; Selby, Talitha M.; Osborn, David L.; Taatjes, Craig A.; Wilson, Kevin R. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Gamma-Ray Spectrometers Using Superconducting Transition Edge Sensors with External Active Feedback Bias

Description: The authors are developing x-ray and gamma-ray spectrometers with high absorption efficiency and high energy-resolution for x-ray and gamma-ray spectroscopy. They are microcalorimeters consisting of a bulk Sn absorber coupled to a Mo/Cu multilayer superconducting transition edge sensor (TES). The authors have measured an energy resolution of 70 eV FWHM for 60 keV incident gamma-rays using electrothermal feedback. They have also operated these microcalorimeters with an external active feedback b… more
Date: September 22, 2000
Creator: Chow, D.T.; van den Berg, M.L.; Loshak, A.; Frank, M.; Barbee, T.W. & Labov, S.E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

X-Ray Photoionized Plasmas in the Laboratory

Description: The advanced spectroscopic capabilities of the new X-ray telescopes Chandra and XMM lead to a need for improved benchmarking of models for the photoionized accretion-disk plasmas which represent over half of known astrophysical X-ray sources. They report the first laboratory experimental results using 120 TW, 180 eV Z-pinch plasmas to drive iron samples into the photoionized equilibrium. The pinch spectrum, temperature, power and uniformity have been characterized in order to qualify it as a ph… more
Date: April 22, 2000
Creator: Heeter, R. F.; Foord, M. E.; Thoe, R. S.; Emig, J. A.; Springer, P. T.; Bailey, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Modification of the x-ray diffraction efficiency of lithium fluoride crystals by surface treatment

Description: Convex-curved crystals of lithium fluoride demonstrate good dispersion and efficiency when used in reflection for x-ray spectral analysis. The crystals are stable and reasonably unaffected by harsh environments. In addition, they are mechanically strong, easily cleavable or machinable, and plastically deformable with heat. In the present study, flat crystal wafers were left either clear as cleaved or were subjected to surface treatment by sandblasting or lapping. Some wafers were then bent in a… more
Date: July 22, 1976
Creator: Sellick, Barton O.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Superconducting High Energy Resolution Gamma-ray Spectrometers

Description: We have demonstrated that a bulk absorber coupled to a TES can serve as a good gamma-ray spectrometer. Our measured energy resolution of 70 eV at 60 keV is among the best measurements in this field. We have also shown excellent agreement between the noise predictions and measured noise. Despite this good result, we noted that our detector design has shortcomings with a low count rate and vulnerabilities with the linearity of energy response. We addressed these issues by implementation of an act… more
Date: February 22, 2002
Creator: Chow, Daniel Tun Lai
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
open access

High spectral resolution measurements for the ARM Program. Year two technical progress report, March 15, 1991--March 15, 1992

Description: This report focuses on the design and fabrication of high spectral resolution FTIR (Fourier Transform Infrared) instrumentation for the CART sites of the Atmospheric Radiation Measurement (ARM) Program. The ultimate objective of this grant is to develop three different types of instruments, named the AERI, AERI-X, and SORT. The Atmospheric Emitted Radiance Interferometer (AERI) is the simplest. It will be available for early deployment at the first ARM site and will be deployable at several loc… more
Date: May 22, 1992
Creator: Revercomb, H. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Integration and Evaluation of a Position Sensor with Continuous Read-Out for use with the Environmental Measurement-While-Drilling Gamma Ray Spectrometer System

Description: The Environmental Measurement-While-Drilling-Gamma Ray Spectrometer (EMWD-GRS) system represents an innovative blend of new and existing technology that provides real-time environmental and drill bit data during drilling operations. The EMWD-GRS technology was demonstrated at Savannah River Site (SRS) F-Area Retention Basin. The EMWD-GRS technology demonstration consisted of continuously monitoring for gamma-radiation-producing contamination while drilling two horizontal boreholes below the bac… more
Date: February 22, 1999
Creator: Lockwood, G. J.; Normann, R. A.; Selph, M. M. & Williams, C. V.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Multichannel CdZnTe Gamma Ray Spectrometer

Description: A 3 cm{sup 3} multichannel gamma spectrometer for DOE applications is under development by Digirad Corporation. The device is based on a position sensitive detector packaged in a compact multi-chip module (MCM) with integrated readout circuitry. The modular, multichannel design will enable identification and quantitative analysis of radionuclides in extended sources, or sources containing low levels of activity. The MCM approach has the advantages that the modules are designed for imaging appli… more
Date: July 22, 1998
Creator: Doty, F. P.; Lingren, C. L.; Apotovsky, B. A.; Brunsch, J.; Butler, J. F.; Collins, T. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Spectral Analysis of Airborne Effluents from Nuclear Facilities and Design of AOTF Spectroradiometer

Description: This report summarizes the spectral analysis and design of an acousto optic tunable filter (AOTF) imaging spectroradiometer for the project SR003. This system will use passive open-path infrared absorption to detect the presence of various source gases.
Date: March 22, 1995
Creator: Villa, E.; Suhre, D. R. & Taylor, L. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Real-Time Analysis of Individual Airborne Microparticles Using Laser Ablation Mass Spectroscopy and Genetically Trained Neural Networks

Description: We are developing a method for analysis of airborne microparticles based on laser ablation of individual molecules in an ion trap mass spectrometer. Airborne particles enter the spectrometer through a differentially-pumped inlet, are detected by light scattered from two CW laser beams, and sampled by a pulsed excimer laser as they pass through the center of the ion trap electrodes. After the laser pulse, the stored ions are separated by conventional ion trap methods. The mass spectra are then a… more
Date: January 22, 1999
Creator: Parker, Eric P.; Rosenthal, Stephen E.; Trahan, Michael W. & Wagner, John S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Sensor systems for the Altair Lunar Lander:

Description: The Altair Lunar Lander will enable astronauts to learn to live and work on the moon for extended periods of time, providing the experience needed to expand human exploration farther into the solar system. My overriding recommendation: Use independent and complementary [sometimes referred to as 'orthogonal'] techniques to disambiguate confounding/interfering signals. E.g.: a mass spectrometer ['MS'], which currently serves as a Majority Constituent Analyzer ['MCA'] can be very valuable in detec… more
Date: December 22, 2009
Creator: Mariella, Raymond, Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Science & Technology Review October 2005

Description: This month's issue has the following articles: (1) Important Missions, Great Science, and Innovative Technology--Commentary by Cherry A. Murray; (2) NanoFoil{reg_sign} Solders with Less Heat--Soldering and brazing to join an array of materials are now Soldering and brazing to join an array of materials are now possible without furnaces, torches, or lead; (3) Detecting Radiation on the Move--An award-winning technology can detect even small amounts An award-winning technology can detect even sma… more
Date: August 22, 2005
Creator: Aufderheide, M. B., III
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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