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/sup 56/Ni and the light curve of Type I supernova

Description: The explanation of SN Type I by radioactive decay of /sup 56/Ni requires a relatively small value of the transparency function M/sub ej//v/sub 9//sup 2/ = 0.22 in units of M/sub solar/'s and 10/sup 9/ cm s/sup -1/ to explain the light curve. A minimum mass of /sup 56/Ni is required to explain the peak and near peak luminosity. Subsequent radioactive decay energy must escape in some other form than optical light in order to explain the rapid early and late time decay. Early ultraviolet and infra… more
Date: July 24, 1980
Creator: Colgate, S.A. & Petschek, A.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Parametrization of net radiation at the surface using data from the Wangara experiment

Description: Hourly Wangara boundary layer data (Clark et al., 1971) was used to substantiate previously derived empirical equations of the surface radiation budget. These equations only require measurements taken by a surface observer in order to be evaluated. A parameterization was made for infrared (IR) radiation. From this procedure, a residual radiation was obtained from the measured daytime net radiation data in order to approximate short wave (SW) radiation. Diurnal trends in radiation and other rela… more
Date: Summer 1980
Creator: Edson, Roger T.
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Calculating the vulnerability of synthetic polymers to autoignition during nuclear flash. Final report

Description: The purpose of our investigation was to determine if the rapid progression of fire to flashover conditions in a furnished room, observed in a 1953 nuclear weapons test at the Nevada Test Site (the Encore Event), might be typical behavior rather than an aberration. If flashover under such conditions is indeed likely, this phenomenon is worth pursuing in view of the increased threat to buildings and human life from possible large-scale fires. We placed special emphasis on fires that occurred in m… more
Date: January 1, 1985
Creator: Hickman, R. & Reitter, T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Survey of thermal imaging technology and applications at the Savannah River Site

Description: This memorandum is an introduction to thermal imaging systems and their use. Emission of infrared radiation from ideal and real materials is described, as are methods of detection in modern thermal imaging systems. Typical specifications and features of commercially available thermal imaging systems are described, and uses of thermal imaging are discussed. At the Savannah River Site (SRS), thermal imaging has been used extensively to measure the temperature of surface water that carries heat fr… more
Date: October 9, 1989
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Review of free electron laser theory and experiments

Description: A review of the major Free Electron Laser (FEL) experiments will be presented. These experiments are designed to produce radiation at wavelengths from the far infrared to the ultraviolet. Different categories of FELs (Compton, Raman, optical klystron, two stage, etc.), as well as the suitability of various types of electron accelerators to power FELs, will also be discussed. Potential applications of the FEL will be summarized.
Date: January 13, 1984
Creator: Prosnitz, D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Power transport to the PDX scoop limiter

Description: Power transport to the PDX graphite scoop limiter was measured during both ohmic- and neutral-beam-heated discharges by observing its front face temperatures using an infrared camera. Measurements were made as a function of plasma density, current, position, fueling mode, and heating power for both co- and counter-neutral beam injection. The measured thermal load on the scoop limiter was 25 to 50% of the total plasma heating power. The measured peak front face midplane temperature was 1500/sup … more
Date: July 1, 1986
Creator: Kugel, H.W.; Bol, K.; Budny, R.; Fonck, R.; Goldston, R.; Grek, B. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Investigation of proposed process sequence for the array automated assembly task: Phase II. Quarterly technical progress report for quarter ending December 29, 1979

Description: A sulfur hexaflouride plasma etch was investigated as a possible surface treatment to improve the performance of the cell, the Radiation Technology Infrared Furnace was qualified for use in the process sequence, and work was initiated on junction clean up by laser scribing through the junction. An evaluation of the minority carrier diffusion length of silicon crystals received from various vendors was also included in this quarters activities. Results are presented and discussed.
Date: February 1, 1980
Creator: Mardesich, N.; Bunyan, S. & Sipperly, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Multiphoton ionization and third-harmonic generation in atoms and molecules

Description: We will discuss recent experiments on multiphoton ionization and third-harmonic generation in rare gases and small molecules using focused laser power densities of 10/sup 9/ to 10/sup 11/ W/cm/sup 2/. Also, some elementary experiments using vacuum ultraviolet light generated by frequency tripling in xenon and krypton will be described. These experiments include absorption and ionization studies using vacuum ultraviolet radiation as well as two-photon ionization using one vacuum ultraviolet phot… more
Date: January 1, 1982
Creator: Miller, J. C. & Compton, R. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of heat transport to forced-flow He II

Description: Analytical and experimental studies of heat transport to forced-flow He II are reported. The work is pertinent to the transfer of He II in space. An analytical model has been developed that establishes a condition for two-phase flow to occur in the transfer line. This condition sets an allowable limit to the heat leak into the transfer line. Experimental measurements of pressure drop and flow meter performances indicate that turbulent He II can be analyzed in terms of classical pressure drop co… more
Date: January 1, 1985
Creator: Dresner, L.; Kashani, A. & Van Sciver, S.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Status of NTD Ge bolometer material and devices

Description: This status report is a direct follow-up to the presentation given at the first IR Detector Technology Workshop which took place at NASA Ames Research Center on July 12 and 13, 1983. The conclusions which we presented at that meeting are still fully valid. In the meantime we have learned more about the physics of hopping conduction at very low temperatures which will be important for bolometer design and operation at ever decreasing temperatures. Resistivity measurements have been extended down… more
Date: August 1, 1985
Creator: Haller, E.E.; Haegel, N.M. & Park, I.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infra-red line IR4 at the NSLS

Description: The authors describe the infra-red beam line which is being constructed at the NSLS. In order to maintain the high brightness at long wavelengths (up to 1 mm) where diffraction becomes a problem, a high aperture extraction port is used. Problems of cooling of the first mirror will also be discussed. Large off axis ellipsoids are used to bring the beam to a secondary focus on a mezzanine floor before entering a monochromator or being collimated for an interferometer.
Date: January 1, 1985
Creator: Williams, G. P.; Takacs, P. Z.; Klaffky, R. W. & Shleifer, M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Design of the NSLS Infrared Beam Line Mirror No. 1

Description: The mechanical design of the Infrared Beam Line Mirror No. 1 (IRBL M1) at the NSLS facility was done with the aid of finite element modeling. Preliminary heat load calculations indicated that the Gaussian peak power density incident on M1 is about 345.8 w/sq. cm. The thermal gradient due to this concentrated high heat density striking M1 may result in undesirable distortions that can seriously impair its function. In addition, the thermal stress might reach levels beyond the yield strength of t… more
Date: January 1, 1985
Creator: Alforque, R.; Takacs, P.; Shleifer, M.; Colbert, J. & Williams, J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of proposed process sequence for the array automated assembly task. Phase II. Quarterly technical progress report, March 28, 1980

Description: Evaluation of infrared drying (at approximately 300/sup 0/C) PX-10 diffusion source in about one minute or less, revealed comparable results to the conventional oven drying at 150/sup 0/C for 15 minutes. Initially investigation of the fritted-nickel paste front contact indicated high series resistance. Series resistance was reduced upon solder dipping. Further experimentation on junction isolation by laser scribing the front edge of finished, non-AR coated, solar cells continued this period. Al… more
Date: April 1, 1980
Creator: Garcia, A.; Bunyan, S. & Wong, B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Safeguards applications of far infrared radiometric techniques for the detection of contraband

Description: A new safeguards system under development employs radiometers in the 100 to 300 GHz spectral band to detect contraband, including shielding materials (used to attenuate the gamma ray emissions from nuclear materials), weapons, or explosives covertly concealed on personnel. Clothing is highly transparent at these frequencies and imaging techniques can detect contraband by its emissivity and reflectivity differences relative to human tissues. Experimental data are presented and sample images are … more
Date: February 1, 1980
Creator: Hodges, D. T.; Reber, E. E.; Foote, F. B. & Schellenbaum, R. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Microprocessor-controlled tester for evaluation of the Self-Energized Credential System (SECS)

Description: The Self-Energized Credential System (SECS) was developed for use in the Plutonium Protection System (PPS) installed at Hanford, Washington. Evaluation and development of the SECS system was enhanced by the use of a microprocessor-controlled portal tester. This tester used infrared (ir) beam sensors to provide information on the direction of travel of the credential wearer and to detect inoperative credentials. A printed record of the portal number, actual code read, time, and direction of the … more
Date: March 1, 1980
Creator: Corlis, N.E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Infrared monitoring of gyrotron windows

Description: A technique for monitoring the gyrotron output window surface temperature with an infrared camera while the gyrotron is in operation has been developed. The IR camera views the window through a perforated waveguide wall, and serves both as a guide for the safe operation at high average power of the tube, as well as an aid in the analysis of new window designs. Window temperatures were studied as a function of a number of parameters, including gun anode voltage, beam current, magnetic field, coo… more
Date: January 1, 1983
Creator: Huey, H.; Lopez, N.; Hu, G.; Choi, E. & Mundie, L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Initial-temperature profiles on the PDX inner toroidal limiter

Description: The temperature profiles resulting from plasma operation on the PDX vertical, large area, inner toroidal limiter have been measured during both ohmic and neutral-beam-heated discharges using a scanning infrared camera. An asymmetric double-peaked temperature profile is seen after neutral-beam-heated discharges. Disruptions in ohmically heated discharges are found to be preceded by a single-peaked deposition and succeeded by an initially symmetric double-peaked deposition. The results were compa… more
Date: September 1, 1983
Creator: Ulrickson, M. & Kugel, H.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The initial scientific program at the NSLS infrared beamline

Description: Unique extraction optics (90 {times} 90 mrads) at the NSLS U4IR line offer high brightness beams at up to mm wavelengths with a {approximately}1ns pulse structure. Radiation from this port has now been carefully characterized and agrees well with calculations, making it 100--1000 times brighter than conventional sources in the middle and far infrared regions. Using rapid scan Michelson interferometers with liquid He cooled bolometer detectors we have been able for the first time to measure mole… more
Date: January 1, 1989
Creator: Williams, G. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Far infrared Faraday-rotation measurement on a reversed-field-pinch plasma

Description: The integral n/sub e/B/sub theta/.dl is measured on the Los Alamos reversed field pinch plasma (ZT-40) by the rotation of the linear polarization of the 185 ..mu..m emission of a CO/sub 2/-pumped CH/sub 2/F/sub 2/ laser. The essence of the method is to monitor phase distortions of the regular beat frequency produced when two counter-rotating circular polarizations, frequency shifted with respect to each other and sent along a common off-center chord through the plasma, are detected behind a lin… more
Date: January 1, 1981
Creator: Bausman, M.D. & Jahoda, F.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Performance of oblique angle of incidence collection systems in the VUV

Description: High rejection filters are difficult enough to achieve in the UV-VIS-IR with known materials and constants. Even more difficult is the design and manufacture of rejection filters in the EUV and VUV given the uncertainty of optical constants and their wide variation over this spectral range. We have begun work to characterize materials from 584 A to 1300 A to verify reported optical constants, in order to design and realize the optimum collection system. 8 refs., 2 figs., 8 tabs.
Date: January 1, 1986
Creator: Keller, G.L.; Scott, M.L. & Mitchell, K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared thermographic study of laser ignition

Description: Pyrotechnic ignition has been studied in the past by making a limited number of discrete temperature-time observations during ignition. Present-day infrared scanning techniques make it possible to record thermal profiles, during ignition, with high spacial and temporal resolution. Data thus obtained can be used with existing theory to characterize pyrotechnic materials and to develop more precise kinetic models of the ignition process. Ignition has been studied theoretically and experimentally … more
Date: July 21, 1986
Creator: Mohler, J.H. & Chow, C.T.S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Investigation of the Interaction of CO Laser Radiation with n-InSb

Description: The Shubnikov-de Haas magneto-resistance oscillations and photoconductivity were experimentally studied in order to investigate the interaction of CO laser radiation with n-InSb at liquid helium temperatures. The roles of various absorption mechanisms on these effects were considered, particularly near the intrinsic band edge. From these measurements an effective electron temperature Tₑ was defined that increased or decreased under illumination, depending upon the strength of the applied electr… more
Date: December 1982
Creator: Hanes, Larry Kenneth
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries
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National synchrotron light source in the infra-red region

Description: A discussion of the utilization of the NSLS in the 1 to 100 micron infra-red spectral region is presented. A comparison is made of the respective brightnesses of the NSLS and of black-body sources. The way in which each source may be utilized with a monochromator is discussed and comparative exit slit brightnesses are calculated for selected cases.
Date: January 1, 1981
Creator: Williams, G. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Non-thermal AGN models

Description: The infrared, optical and x-ray continua from radio quiet active galactic nuclei (AGN) are explained by a compact non-thermal source surrounding a thermal ultraviolet emitter, presumably the accretion disk around a supermassive black hole. The ultraviolet source is observed as the ''big blue bump.'' The flat (..cap alpha.. approx. = .7) hard x-ray spectrum results from the scattering of thermal ultraviolet photons by the flat, low energy end of an electron distribution ''broken'' by Compton los… more
Date: December 1, 1986
Creator: Band, D.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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