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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.
Partner: UNT Libraries Government Documents Department
open access

Phased-array antenna control by a monolithic photonic integrated circuit, COMPASS

Description: Phased-array antenna systems are well known for rapid beam steering and their ability to bring high power to the target. Such systems are also quite complex and heavy, which have limited their usefulness. The issues of weight, size, power use, and complexity have been addressed through a system named COMPASS (Coherent Optical Monolithic Phased Array Steering System). All phased-array antenna systems need: (1) small size; (2) low power use; (3) high-speed beam steering; and (4) digitally-control… more
Date: January 1, 1991
Creator: Kravitz, S. H.; Hietala, V. M.; Vawter, G. A. & Meyer, W. J.
Partner: UNT Libraries Government Documents Department
open access

Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: Dense-phase pneumatic transport is an attractive means of conveying solids. Unfortunately, because of the high solid concentrations, this transport method is a difficult regime in which to carry out detailed measurements. Hence most details of the flow are unknown. In this context, the main objective of this work is to develop probes for local measurements of solid velocity and holdup in dense gas-solid flows. Because we anticipate the recent theories of rapid granular flows will bring insight … more
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Recent Developments in Microshell-Tipped Optical Fibers as High-Pressure Shock Detectors

Description: We describe ongoing development and characterization of Microshell-tipped optical fibers used as impact sensors. We observed a risetime of 15 ns when the probe is used to measure a detonation wave in PETN. We report successful development of two nondestructive tests, radiography and fluorescence, to check the integrity of the sensor. The sensor is now commercially available. 5 refs., 3 figs.
Date: January 1, 1985
Creator: Mayer, F. J.; Maynard, R. L.; Musinski, D. L.; Schmerberg, N. W.; Wixom, M. R. & Benjamin, R. F.
Partner: UNT Libraries Government Documents Department
open access

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.
Partner: UNT Libraries Government Documents Department
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Development and utilization of new diagnostics for dense-phase pneumatic transport

Description: In 1988, we proposed a program to develop new diagnostics for dense gas-solid suspensions, with particular interest toward the dense pneumatic transport of cohesive solid plugs. This program included three main objectives, as follows: to develop probes for local measurements of (1) local particle volume fraction and (2) individual particle velocities in dense gas-solid flows; and (3) to construct a bench-scale setup for transporting dense cohesive solid plugs and to analyze data from the result… more
Date: March 2, 1992
Creator: Louge, M. & Jenkins, J.T.
Partner: UNT Libraries Government Documents Department
open access

Support of the NATO Effects Task Group by Los Alamos National Laboratory

Description: A method is outlined for measuring the transient attenuation of optical fibers and/or cables exposed to a pulse of radiation (gamma rays, x-rays, electrons, protons, neutrons, etc). It can be employed to determine the level of radiation-induced attenuation (in units of dB/km as a function of time) produced in single-mode or multi-mode optical fibers, in either cabled or uncabled form, due to pulsed exposure to radiation. Co{sup 60} radiation-induced attenuation is measured by optical time domai… more
Date: January 1, 1991
Creator: Lyons, P. B.
Partner: UNT Libraries Government Documents Department
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Application of pulse compression and shaping to the FEL photoelectric injector

Description: We discuss the application of self-phase modulation and grating pulse compression to the generation of temporally trapezoidal optical pulses for controlling the electron beam emitance and energy spread in an FEL photoelectric injector. Pulse compression i n a single-stage pulse compressor, with background reduction based on the nonlinear birefringence of the optical fiber, yields 3-ps, compressed pulses without background pedestals or sidelopes. Trapezoidal, flat-topped pulses with 20-ps FWHM a… more
Date: January 1, 1988
Creator: Nguyen, D. C.; Watkins, D. E. & Weber, M. E.
Partner: UNT Libraries Government Documents Department
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Optical data transmission at the superconducting super collider

Description: Digital and analog data transmissions via fiber optics for the Superconducting Super Collider have been investigated. The state of the art of optical transmitters, low loss fiber waveguides, receivers and associated electronics components are reviewed and summarized. Emphasis is placed on the effects of the radiation environment on the performance of an optical data transmission system components. Also, the performance of candidate components of the wide band digital and analog transmission sys… more
Date: February 1, 1989
Creator: Leskovar, B.
Partner: UNT Libraries Government Documents Department
open access

Coupling between plastic scintillators and light fibers for remote detection of x-rays

Description: Plastic scintillators can be coupled to light fibers to make small, simple, and inexpensive x-ray detectors. These detectors have been developed for use at the Nevada Test Site (NTS) for the remote detection of x-rays. Light produced in the scintillator can be transmitted by the fiber for several hundred meters to a photodetector, which is usually a streak camera or a photomultiplier tube. The use of a streak camera allows many channels to be recorded simultaneously. A parameter study has been … more
Date: July 18, 1985
Creator: Perry, T.S. & Molitoris, J.J.
Partner: UNT Libraries Government Documents Department
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(Gene sequencing by scanning molecular exciton microscopy)

Description: This report details progress made in setting up a laboratory for optical microscopy of genes. The apparatus including a fluorescence microscope, a scanning optical microscope, various spectrometers, and supporting computers is described. Results in developing photon and exciton tips, and in preparing samples are presented. (GHH)
Date: January 1, 1991
Partner: UNT Libraries Government Documents Department
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Progress in the development of scintillating optical fibers

Description: Starting with 1 inch diameter PVT scintillator as a preform, the authors have drawn fibers of several diameters ranging from 1 to 4 mm. These fibers have been coated in line with the draw to form optical fibers. Several cladding materials whose index of refraction ranges from 1.35 to 1.55 have been used. The most successful fiber has been obtained with an extra thick (200 micron) cladding of silicone in combination with a linear draw, as opposed to a spool draw. This fiber is acceptable, but it… more
Date: January 1, 1983
Creator: Borenstein, S.R. & Strand, R.C.
Partner: UNT Libraries Government Documents Department
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Demonstration of Femtosecond-Phase Stabilization in 2 km OpticalFiber

Description: Long-term phase drifts of less than a femtosecond per hour have been demonstrated in a 2 km length of single-mode optical fiber, stabilized interferometrically at 1530 nm. Recent improvements include a wide-band phase detector that reduces the possibility of fringe jumping due to fast external perturbations of the fiber and locking of the master CW laser wavelength to an atomic absorption line. Mode-locked lasers may be synchronized using two wavelengths of the comb, multiplexed over one fiber,… more
Date: June 1, 2007
Creator: Staples, J. W.; Wilcox, R. & Byrd, J. M.
Partner: UNT Libraries Government Documents Department
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Condition monitoring through advanced sensor and computational technology : final report (January 2002 to May 2005).

Description: The overall goal of this joint research project was to develop and demonstrate advanced sensors and computational technology for continuous monitoring of the condition of components, structures, and systems in advanced and next-generation nuclear power plants (NPPs). This project included investigating and adapting several advanced sensor technologies from Korean and US national laboratory research communities, some of which were developed and applied in non-nuclear industries. The project team… more
Date: May 1, 2005
Creator: Kim, Jung-Taek (Korea Atomic Energy Research Institute, Daejon, Korea) & Luk, Vincent K.
Partner: UNT Libraries Government Documents Department
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Accuracy of Analog Fiber-Optic Links in Pulsed Radiation Environments

Description: Interferometric fiber-optic links used in pulsed-power experiments are evaluated for accuracy in the presence of radiation fields which alter fiber transmission. Amplitude-modulated format (e.g., Mach-Zehnder) and phase-modulated formats are compared. Historically, studies of radiation effects on optical fibers have focused on degradation and recovery of the fibers transmission properties; such work is either in the context of survivability of fibers in catastrophic conditions or suitability of… more
Date: December 1, 2007
Creator: E. K. Miller, G. S. Macrum, I. J. McKenna, et al.
Partner: UNT Libraries Government Documents Department
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Diagnostic Components in Harsh Radiation Environments: Possible Overlap in R&D Requirements of IC and MF Systems

Description: The next generation of large scale fusion devices--ITER/LMJ/NIF--will require diagnostic components to operate in environments far more severe than those encountered in present facilities. This harsh environment will be induced by fluxes of neutrons, gamma rays, energetic ions, electromagnetic radiation, and in some cases debris and shrapnel, at levels several orders of magnitude higher than those experienced in today's devices. For several years the question of possible synergy between inertia… more
Date: May 8, 2008
Creator: Bourgade, J. L.; Costley, A. E.; Reichle, R.; Hodgson, E. R.; Hsing, W.; Glebov, V. et al.
Partner: UNT Libraries Government Documents Department
open access

High Altitude Aerial Natural Gas Leak Detection System

Description: The objective of this program was to develop and demonstrate a cost-effective and power-efficient advanced standoff sensing technology able to detect and quantify, from a high-altitude (> 10,000 ft) aircraft, natural gas leaking from a high-pressure pipeline. The advanced technology is based on an enhanced version of the Remote Methane Leak Detector (RMLD) platform developed previously by Physical Sciences Inc. (PSI). The RMLD combines a telecommunications-style diode laser, fiber-optic comp… more
Date: December 31, 2006
Creator: Wainner, Richard T.; Frish, Mickey B.; Green, B. David; Laderer, Matthew C.; Allen, Mark G. & Morency, Joseph R.
Partner: UNT Libraries Government Documents Department
open access

Intelligent Monitoring System With High Temperature Distributed Fiberoptic Sensor For Power Plant Combustion Processes

Description: The objective of the proposed work is to develop an intelligent distributed fiber optical sensor system for real-time monitoring of high temperature in a boiler furnace in power plants. Of particular interest is the estimation of spatial and temporal distributions of high temperatures within a boiler furnace, which will be essential in assessing and controlling the mechanisms that form and remove pollutants at the source, such as NOx. The basic approach in developing the proposed sensor system … more
Date: December 26, 2005
Creator: Lee, Kwang Y.; Yin, Stuart S. & Boheman, Andre
Partner: UNT Libraries Government Documents Department
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Limitations on High Data Rate Optical Fiber Transmission Systems Due to Transmission Impairment

Description: This project supplemented our regular DOE grant from the Basic Energy Sciences organization with the goal of fostering industrial partnerships and student internships. During the project period, we have interacted with between 15 and 20 companies in the optical fiber telecommunications equipment industry, and our students have participated in a number of highly visible projects with companies such as Ciena, Science Applications International Corporation, KDD, ATT, Virtual Photonics, Inc., Phaet… more
Date: March 15, 2002
Creator: Menyuk, Curtis R.
Partner: UNT Libraries Government Documents Department
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Fiberoptics-Based Instrumentation for Storage Ring BeamDiagnostics

Description: In several cases, coupling synchrotron light into opticalfibers can substantially facilitate the use of beam diagnosticinstrumentation, that measures longitudinal beam properties by detectingsynchrotron radiation. It has been discussed in [1]with some detail, howfiberoptics can bring the light at relatively large distances from theaccelerator, where a variety of devices can be used to measure beamproperties and parameters. Light carried on a fiber can be easilyswitched between instruments so th… more
Date: April 18, 2007
Creator: Byrd, John M.; De Santis, Stefano & Yin, Yan
Partner: UNT Libraries Government Documents Department
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Optical Fiber Sensor Instrumentation for Slagging Coal Gasifiers

Description: Coal gasifier is one of the most promising solutions for clean fossil energy. Refractory thickness monitoring and online real-time temperature measurement is needed for improved reliability and advanced process control for current and future generation power plants. The objective of this program is to design and implement an optical fiber based sensing system that could potentially be used to monitor refractory wall thickness and temperature inside a coal gasifier. For the thickness monitoring,… more
Date: July 19, 2008
Creator: Wang, Anbo & Cooper, Kristie
Partner: UNT Libraries Government Documents Department
open access

Hydrogen Optical Fiber Sensors

Description: Optically-based hydrogen sensors promise to deliver an added level of safety as hydrogen and fuel cell technologies enter the mainstream. More importantly, they offer reduced power consumption and lower cost, which are desirable for mass production applications such as automobiles and consumer appliances. This program addressed two of the major challenges previously identified in porous optrode-based optical hydrogen sensors: sensitivity to moisture (ambient humidity), and interference from the… more
Date: July 28, 2008
Creator: Lieberman, Robert A.; Beshay, Manal & Cordero, Steven R.
Partner: UNT Libraries Government Documents Department
open access

Optical Comb Generation for Streak Camera Calibration for Inertial Confinement Fusion Experiments

Description: The National Ignition Facility (NIF) at Lawrence Livermore National Laboratory (LLNL) is coming on-line to support physics experimentation for the U.S. Department of Energy (DOE) programs in Inertial Confinement Fusion (ICF) and Stockpile Stewardship (SS). Optical streak cameras are an integral part of the experimental diagnostics instrumentation at NIF. To accurately reduce streak camera data a highly accurate temporal calibration is required. This article describes a technique for simultaneou… more
Date: September 18, 2008
Creator: Ronald Justin, Terence Davies, Frans Janson, Bruce Marshall, Perry Bell, Daniel Kalantar, Joseph Kimbrough, Stephen Vernon, Oliver Sweningsen
Partner: UNT Libraries Government Documents Department
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