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Alignment and focusing device for a multibeam laser system

Description: Large inertial confinement fusion laser systems have many beams focusing on a small target. The Antares system is a 24-beam CO/sub 2/ pulse laser. To produce uniform illumination, the 24 beams must be individually focused on (or near) the target's surface in a symmetric pattern. To assess the quality of a given beam, we will locate a Smartt (point diffraction) interferometer at the desired focal point and illuminate it with an alignment laser. The resulting fringe pattern shows defocus, lateral… more
Date: January 1, 1980
Creator: Sweatt, W.C.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optimization of a VISAR for measuring flyer-plate velocities

Description: VISAR (Velocity Interferometer System for Any Reflector) is commonly used for measuring flyer-plate velocities up to 6 km/s. Flyer plates can travel as much as 1 mm, which is large compared to usual depth-of-focus requirements for VISARs. Flyer plates are explosively driven, or driven by some other very energetic means; as such, they must be tested in a chamber, which will contain the explosion. Routing the laser beam to the chamber and the signal beam to the VISAR can be done safely and easily… more
Date: May 6, 1992
Creator: Sweatt, W. C.; Crump, O. B., Jr. & Brigham, W. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Method and apparatus for aerosol-particle absorption spectroscopy. [DOE patent application]

Description: A method and apparatus are described for determining the absorption spectra, and other properties, of aerosol particles. A heating beam source provides a beam of electromagnetic energy which is scanned through the region of the spectrum which is of interest. Particles exposed to the heating beam which have absorption bands within the band width of the heating beam absorb energy from the beam. The particles are also illuminated by light of a wave length such that the light is scattered by the pa… more
Date: June 25, 1981
Creator: Campillo, Anthony J. & Lin, Horn-Bond
Item Type: Refine your search to only Patent
Partner: UNT Libraries Government Documents Department
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Phase Transformations in Alumina. Technical Report, May to December 1961

Description: e transformation studies showed that synthetic aluminas produced in the laboratory were not transformed to alpha alumina at 400 to 700' deg n the presence of nitric acid and water vapor. Amorphous aluminn produced in the pilot plant was transformed to alpha alumina. This indicated that the amorphous alumina produced in the pilot plant is structurally predisposed to form alpha alumina. Most additives did not appear to have any special effects. Lithium formed zeta alumina, LiAl/sub 5/O/sub 8/. Ph… more
Date: December 1, 1961
Creator: Eding, H J; Huggins, M L & Brown, A G
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Experimental study of the steady natural convection in a horizontal annulus with irregular boundaries

Description: The natural convective heat transfer across an annulus with irregular boundaries was studied using a Mach-Zehnder interferometer. The annulus was formed by an inner hexagonal cylinder and an outer concentric circular cylinder. This configuration models, in two dimensions, a liquid metal fast breeder reactor spent fuel subassembly inside a shipping container. During the test, the annulus was filled with a single gas, either neon, air, argon, krypton, or xenon, at a pressure of about 0.5 MPa. Fro… more
Date: January 1, 1980
Creator: Boyd, R.D.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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VISAR: interferometer quadrature signal recording by electronic streak camera

Description: This short paper describes a demonstration to record the four quadrature signals from a push-pull VISAR velocity interferometer using an electronic streak camera. Optical fibers were used to transmit the interferometer outputs to the camera photocathode. Brightness variations of these signals were recorded on film during the experiment. Velocity information was later recovered from this record to give a continuous velocity history. Anticipated advantages over previous methods are increased time… more
Date: January 1, 1985
Creator: Hemsing, W.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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X-ray intensity interferometer for undulator radiation

Description: Intensity interferometry is well established with visible light but has never been demonstrated with x-radiation. We propose to measure the transverse coherence of an x-ray beam, for the first time, using the method of Hanbury Brown and Twiss. The x-ray interferometer consists of an array of slits, a grazing incidence reflective beamsplitter, a pair of fast multichannel plate detectors and a broadband, low-noise correlator circuit. The NSLS X1 or X13 soft x-ray undulator will supply the partial… more
Date: January 1, 1991
Creator: Gluskin, E.; McNulty, I.; Viccaro, P.J. (Argonne National Lab., IL (United States)) & Howells, M.R. (Lawrence Berkeley Lab., CA (United States))
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Undulator based scanning microscope at the National Synchrotron Light Source

Description: A second generation scanning soft x-ray microscope is under construction, designed to utilize the dramatic increase in source bightness available at the soft x-ray undulator. The new instrument is expected to reduce image acquisition time by a factor of about 100, and to improve resolution, stability, and reproducibility.
Date: January 1, 1986
Creator: Rarback, H.; Shu, D.; Ade, H.; Jacobsen, C.; Kirz, J.; McNulty, I. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Optical diagnostics on dense Z-pinch plasmas

Description: A novel point-diffraction'' interferometer has been implemented on the Los Alamos Solid Fiber Z-Pinch experiment. The laser beam is split into two legs after passing through the plasma. The reference leg is filtered with a pin-hole aperture and recombined with the other leg to form an interferogram. This allows compact mounting of the optics and relative ease of alignment. The Z-Pinch experiment employs a pulsed-power generator that delivers up to 700 KA with a 100ns rise-time through a fiber o… more
Date: January 1, 1992
Creator: Riley, R.A. Jr.; Lovberg, R.H.; Shlachter, J.S. & Scudder, D.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental study of finite Larmor radius effects

Description: Linear Z-pinches in Ar, Kr, Xe, N/sub 2/, and He are experimentally studied in regimes where strong finite Larmor radius effects could provide a significant stabilizing effect. Scaling arguments show that for deuterium such a pinch has an electron line density of order 2 x 10/sup 15//cm. For higher Z plasmas a higher line density is allowed, the exact value of which depends on the average ion charge. The pinch is formed by puffing gas axially through the cathode towards the anode of an evacuate… more
Date: August 1, 1980
Creator: Struve, K.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Streak camera recording of interferometer fringes

Description: The use of an electronic high-speed camera in the streaking mode to record interference fringe motion from a velocity interferometer is discussed. Advantages of this method over the photomultiplier tube-oscilloscope approach are delineated. Performance testing and data for the electronic streak camera are discussed. The velocity profile of a mylar flyer accelerated by an electrically exploded bridge, and the jump-off velocity of metal targets struck by these mylar flyers are measured in the cam… more
Date: July 14, 1977
Creator: Parker, N. L. & Chau, H. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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VISAR: 2 1/2 minutes for data reduction

Description: Starting with a pair of signals obtained by electronically subtracting photodetector outputs from any VISAR, it is possible to plot velocity vs time, velocity vs distance, and distance vs time in 2 1/2 min using an LSI-11/23 computer. This includes time for six iterations of time shift with the resulting polar plots and operator interactions. The velocity calculating algorithm and a flow chart of the computer program are presented.
Date: January 1, 1983
Creator: Hemsing, W.F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experimental and theoretical research in applied plasma physics

Description: This report discusses research in the following areas: fusion theory and computations; theory of thermonuclear plasmas; user service center; high poloidal beta studies on PBX-M; fast ECE fluctuation diagnostic for balloning mode studies; x-ray imaging diagnostic; millimeter/submillimeter-wave fusion ion diagnostics; small scale turbulence and nonlinear dynamics in plasmas; plasma turbulence and transport; phase contrast interferometer diagnostic for long wavelength fluctuations in DIII-D; and c… more
Date: January 1, 1992
Creator: Porkolab, M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Spatially resolved localized vibrational mode spectroscopy of carbon in liquid encapsulated Czochralski grown gallium arsenide wafers

Description: Substitutional carbon on an arsenic lattice site is the shallowest and one of the most dominant acceptors in semi-insulating Liquid Encapsulated Czochralski (LEC) GaAs. However, the role of this acceptor in determining the well known W'' shape spatial variation of neutral EL2 concentration along the diameter of a LEC wafer is not known. In this thesis, we attempt to clarify the issue of the carbon acceptor's effect on this W'' shaped variation by measuring spatial profiles of this acceptor alon… more
Date: April 1, 1988
Creator: Yau, Waifan.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Short wavelength interferometer for ITER

Description: There is a need for a real time, reliable density measurement compatible with the restricted access and radiation environment on ITER. Due to the large plasma path length, high density and field, refraction and Faraday rotation effects makes the use of contemporary long wavelength (>50{mu}m) interferometers impractical. In this paper we consider the design of a short wavelength vibration compensated interferometer which allows operation without a prohibitively large vibration isolated structure… more
Date: April 1, 1992
Creator: Snider, R. T. & Carlstrom, T. N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Versatile real-time interferometer phase-detection system using high-speed digital techniques

Description: This paper describes the basic design and philosophy of a versatile real-time interferometer phase-detection system to be used on the 2XIIB and TMX magnetic-fusion experiments at Lawrence Livermore Laboratory. This diagnostics system is a satellite to a host computer and uses high-speed emitter-coupled logic techniques to derive data on real-time phase relationships. The system's input signals can be derived from interferometer outputs over a wide range of reference frequencies. An LSI-11 micro… more
Date: October 1, 1977
Creator: Mendell, D.S. & Willett, G.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Infrared synchrotron radiation instrumentation and applications

Description: Infrared synchrotron radiation (IRSR) in the wavelength range from 1{mu}m to {approximately}1cm has now been used quite extensively both in Japan at UVSOR, Okasaki and in the United States at the NSLS, Brookhaven. The use of IRSR poses many new challenges, none the least of which is the fact that the radiation covers four decades of energy and is also very divergent and subject to diffraction. However the advantages are particularly significant due to the 1000 fold increase in brightness availa… more
Date: January 1, 1991
Creator: Williams, G. P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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VISAR: Line-imaging interferometer

Description: A line-imaging Velocity Interferometer System for Any Reflector (VISAR) was applied to measure velocity across the diameter of a metal plate explosively accelerated to 5.5 km/s. Amplified, single- frequency laser light was focused to illuminate a line on the metal surface. The line's image was focused through the interferometer to a streak camera that swept in time and recorded directly on film. During the experiment, the Doppler-shift caused motion of the interference fringes. Analysis of the … more
Date: January 1, 1991
Creator: Hemsing, W. F.; Mathews, A. R.; Warnes, R. H.; George, M. J. & Whittemore, G. R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Lower hybrid heating associated with mode conversion on the Wisconsin octupole

Description: This thesis addresses the following key issues in the lower hybrid frequency range: 1. What are the importent physics aspects of wave propagation and heating in an experimental situation. 2. How effective is plasma heating in the complex magnetic field configuration of the octupole. Experimental work is accomplished by launching 1-10ms pulses of up to 40kW of radio frequency power at 140MHz corresponding to the hot plasma lower hybrid resonance in the octupole. A diploe antenna which is moveabl… more
Date: August 1, 1979
Creator: Owens, T. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Fizeau plasma interferometer

Description: This paper describes a technique by which the sensitivity of plasma interferometers can be increased. Stabilization and fractional fringe measurement techniques have improved to the point where additional optical sensitivity could be useful. (MOW)
Date: January 1, 1980
Creator: Frank, A.M.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Applications of the lateral shearing interferometer in measurement of synchrotron radiation optical elements

Description: The use of a single plate shearing, or Murty, interferometer for measuring the surface quality of several optical elements is reviewed and several results are given. The principle of the Murty interferometer is also explained. (LEW)
Date: November 1, 1987
Creator: Liu, Wu-ming; Takacs, P. Z. & Siddons, D. P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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