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Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

A Steerable Laser System for Atmospheric Monitoring at the High Resolution Flys Eye  

E-Print Network [OSTI]

and radiometer . The energy 2 released into the sky is determined by multiplying this measurementOG 4.5.10 A Steerable Laser System for Atmospheric Monitoring at the High Resolution Flys Eye J. R. Mumford , R. C. Gray , L. R. Wiencke for the 1 1 1 High Resolution Flys Eye Collaboration 1. Physics

2

High-Resolution Optical Coherence Tomography-Guided Laser Ablation of Surgical Tissue1  

E-Print Network [OSTI]

High-Resolution Optical Coherence Tomography-Guided Laser Ablation of Surgical Tissue1 Stephen A Hospital, Boston, Massachusetts 02114 Submitted for publication September 17, 1998 Background. Optical coherence tomography (OCT) is a compact high-speed imaging technology which uses infrared light to acquire

Boppart, Stephen

3

Laser hazard analysis for LASIRIS Model MAG-501L-670M-1000-45[degree]-K diode laser associated with high resolution pulsed scanner.  

SciTech Connect (OSTI)

A laser hazard analysis and safety assessment was performed for the LASIRISTM Model MAG-501L-670M-1000-45o-K diode laser associated with the High Resolution Pulse Scanner based on the ANSI Standard Z136.1-2000, American National Standard for the Safe Use of Lasers and the ANSI Standard Z136.6-2000, American National Standard for the Safe Use of Lasers Outdoors. The laser was evaluated for both indoor and outdoor use.

Augustoni, Arnold L.

2004-11-01T23:59:59.000Z

4

Laser Doppler field sensor for high resolution flow velocity imaging without camera  

SciTech Connect (OSTI)

In this paper we present a laser sensor for highly spatially resolved flow imaging without using a camera. The sensor is an extension of the principle of laser Doppler anemometry (LDA). Instead of a parallel fringe system, diverging and converging fringes are employed. This method facilitates the determination of the tracer particle position within the measurement volume and leads to an increased spatial and velocity resolution compared to conventional LDA. Using a total number of four fringe systems the flow is resolved in two spatial dimensions and the orthogonal velocity component. Since no camera is used, the resolution of the sensor is not influenced by pixel size effects. A spatial resolution of 4 {mu}m in the x direction and 16 {mu}m in the y direction and a relative velocity resolution of 1x10{sup -3} have been demonstrated up to now. As a first application we present the velocity measurement of an injection nozzle flow. The sensor is also highly suitable for applications in nano- and microfluidics, e.g., for the measurement of flow rates.

Voigt, Andreas; Bayer, Christian; Shirai, Katsuaki; Buettner, Lars; Czarske, Juergen

2008-09-20T23:59:59.000Z

5

Analysis of high resolution scatter images from laser damage experiments performed on KDP  

SciTech Connect (OSTI)

Interest in producing high damage threshold KH{sub 2}PO{sub 4} (KDP) and (D{sub x}H{sub 1-x}){sub 2}PO{sub 4} (KD*P, DKDP) for optical switching and frequency conversion applications is being driven by the system requirements for the National Ignition Facility (NIF) at Lawrence Livermore National Lab (LLNL). Historically, the path to achieving higher damage thresholds has been to improve the purity of crystal growth solutions. Application of advanced filtration technology has increased the damage threshold, but gives little insight into the actual mechanisms of laser damage. We have developed a laser scatter diagnostic to better study bulk defects and laser damage mechanisms in KDP and KD*P crystals. This diagnostic consists of a cavity doubled, kilohertz class, Nd:YLF laser (527 nm) and high dynamic range CCD camera which allows imaging of bulk scatter signals. With it, we have performed damage tests at 355 nm on four different {open_quotes}vintages{close_quotes} of KDP crystals, concentrating on crystals produced via fast growth methods. We compare the diagnostic`s resolution to LLNL`s standard damage detection method of 100X darkfield microscopy and discuss its impact on damage threshold determination. We have observed the disappearance of scatter sites upon exposure to subthreshold irradiation. In contrast, we have seen scatterers appear where none previously existed. This includes isolated, large (high signal) sites as well as multiple small scatter sites which appear at fluences above 7 J/cm{sup 2} (fine tracking). However, we have not observed a strong correlation of preexisting scatter sites and laser damage sites. We speculate on the connection between the laser-induced disappearance of scatter sites and the observed increase in damage threshold with laser conditioning.

Runkel, M.; Woods, B.; Yan, M. [and others

1996-01-05T23:59:59.000Z

6

High-resolution multi-heterodyne spectroscopy based on Fabry-Perot quantum cascade lasers  

SciTech Connect (OSTI)

In this Letter, we present a method of performing broadband mid-infrared spectroscopy with conventional, free-running, continuous wave Fabry-Perot quantum cascade lasers (FP-QCLs). The measurement method is based on multi-heterodyne down-conversion of optical signals. The sample transmission spectrum probed by one multi-mode FP-QCL is down-converted to the radio-frequency domain through an optical multi-heterodyne process using a second FP-QCL as the local oscillator. Both a broadband multi-mode spectral measurement as well as high-resolution (?15?MHz) spectroscopy of molecular absorption are demonstrated and show great potential for development of high performance FP-laser-based spectrometers for chemical sensing.

Wang, Yin; Wang, Wen; Wysocki, Gerard, E-mail: gwysocki@princeton.edu [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Soskind, Michael G. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08540 (United States); Department of Electrical Engineering, Rutgers University, New Brunswick, New Jersy 08901 (United States)

2014-01-20T23:59:59.000Z

7

High-resolution mapping of quantum efficiency of silicon photodiode via optical-feedback laser microthermography  

SciTech Connect (OSTI)

We map the external quantum efficiency (QE) distribution of a silicon photodiode (PD) sample via a thermographic imaging technique based on optical-feedback laser confocal microscopy. An image pair consisting of the confocal reflectance image and the 2D photocurrent map is simultaneously acquired to delineate the following regions of interest on the sample: the substrate, the n-type region, the pn overlay, and the bonding pad. The 2D QE distribution is derived from the photocurrent map to quantify the optical performance of these sites. The thermal integrity of the sample is then evaluated by deriving the rate of change of QE with temperature T at each point on the silicon PD. These gradient maps function not only as stringent measures of local thermal QE activity but they also expose probable defect locations on the sample at high spatial resolution - a capability that is not feasible with existing bulk measurement techniques.

Cemine, Vernon Julius; Blanca, Carlo Mar; Saloma, Caesar

2006-09-20T23:59:59.000Z

8

An attempt to study LiH and Li{sub 2} molecules by high resolution pulsed laser spectroscopy  

SciTech Connect (OSTI)

As we start a program to study alkali hydrides and dimers, we have developed a two-step photoionisation experiment on Li{sub 2} molecules based on the use of an atomic beam and two pulsed dye lasers. The first resonant step which excites the A {sup 1}{sigma}{sub u}{sup +}-X {sup 1}{sigma}{sub g}{sup +}Li{sub 2} dimer systems is a home-made cw-seeded DCM dye laser with a laser linewidth of 55 MHz (FWHM) and near the Fourier transform limit. The second step is a larger width fixed frequency UV laser which allows the photoionisation of the selectively excited molecules. The three {sup 6}Li{sub 2}, {sup 6}Li {sup 7}Li and {sup 7}Li{sub 2} spectra are recorded simultaneously by the use of a doubly-accelerating time-of-flight ion analyser. Comparison between recorded and calculated absorption spectra using Dunham parameters found in the literature is satisfactory. To develop similar pulsed high-resolution investigations in LiH, we have characterized our molecular beam by using the laser induced fluorescence (LIF) technique with a cw blue dye laser. Two Franck-Condon LiH Doppler-free resonances have been observed.

Bouloufa, Nadia; Cabaret, Louis; Cacciani, Patrice; Camus, Pierre; Pitcheev, Boris; Vetter, Raymond [Laboratoire Aime Cotton, CNRS II, Bat 505, Campus d'Orsay, 91405 Orsay Cedex (France)

1998-12-16T23:59:59.000Z

9

High resolution data acquisition  

DOE Patents [OSTI]

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock (38) pulse train (37) and analog circuitry (44) for generating a triangular wave (46) synchronously with the pulse train (37). The triangular wave (46) has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter (18, 32) forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter (26) counts the clock pulse train (37) during the interval to form a gross event interval time. A computer (52) then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

Thornton, Glenn W. (Los Alamos, NM); Fuller, Kenneth R. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

10

High resolution data acquisition  

DOE Patents [OSTI]

A high resolution event interval timing system measures short time intervals such as occur in high energy physics or laser ranging. Timing is provided from a clock, pulse train, and analog circuitry for generating a triangular wave synchronously with the pulse train (as seen in diagram on patent). The triangular wave has an amplitude and slope functionally related to the time elapsed during each clock pulse in the train. A converter forms a first digital value of the amplitude and slope of the triangle wave at the start of the event interval and a second digital value of the amplitude and slope of the triangle wave at the end of the event interval. A counter counts the clock pulse train during the interval to form a gross event interval time. A computer then combines the gross event interval time and the first and second digital values to output a high resolution value for the event interval.

Thornton, G.W.; Fuller, K.R.

1993-04-06T23:59:59.000Z

11

High resolution soft x-ray spectroscopy of low Z K-shell emission from laser-produced plasmas  

SciTech Connect (OSTI)

A large radius, R = 44.3 m, High Resolution Grating Spectrometer (HRGS) with 2400 line/mm variable line spacing has been designed for laser-produced plasma experiments conducted at the Lawrence Livermore National Laboratory Jupiter Laser Facility. The instrument has been run with a low-noise, charge-coupled device detector to record high signal-to-noise spectra in the 10-50 {angstrom} wavelength range. The instrument can be run with a 10-20 {micro}m wide slit to achieve the best spectral resolving power, approaching 1000 and similar to crystal spectrometers at 12-20 {angstrom}, or in slitless operation with a small symmetrical emission source. We describe preliminary spectra emitted from various H-like and He-like low Z ion plasmas heated by 100-500 ps (FWHM), 527 nm wavelength laser pulses. This instrument can be developed as a useful spectroscopy platform relevant to laboratory-based astrophysics as well as high energy density plasma studies.

Dunn, J; Magee, E W; Shepherd, R; Chen, H; Hansen, S B; Moon, S J; Brown, G V; Gu, M; Beiersdorfer, P; Purvis, M A

2008-05-21T23:59:59.000Z

12

High-resolution multi-MeV x-ray radiography using relativistic laser-solid interaction  

SciTech Connect (OSTI)

When high intensity ({>=}10{sup 19} W cm{sup -2}) laser light interacts with matter, multi-MeV electrons are produced. These electrons can be utilized to generate a MeV bremsstrahlung x-ray emission spectrum as they propagate into a high-Z solid target positioned behind the interaction area. The short duration (<10 ps) and the small diameter (<500 {mu}m) of the x-ray pulse combined with the MeV x-ray spectrum offers an interesting alternative to conventional bremsstrahlung x-ray sources based on an electron accelerator used to radiograph dense, rapidly moving objects. In experiments at the Omega EP laser, a multi-MeV x-ray source is characterized consistently with number of independent diagnostics. An unfiltered x-ray dose of approximately 2 rad in air at 1 m and a source diameter of less than 350 {mu}m are inferred. Radiography of a complex and high area density (up to 61 g/cm{sup 2}) object is then performed with few hundred microns spatial resolution.

Courtois, C.; Compant La Fontaine, A.; Barbotin, M.; Bazzoli, S.; Brebion, D.; Bourgade, J. L.; Gazave, J.; Lagrange, J. M.; Landoas, O.; Le Dain, L.; Lefebvre, E.; Pichoff, N. [CEA, DAM, DIF, F-91297 Arpajon (France); Edwards, R.; Aedy, C.; Biddle, L.; Drew, D.; Gardner, M.; Ramsay, M.; Simons, A.; Sircombe, N. [AWE Plc., Aldermaston, Reading RG7 4PR (United Kingdom)

2011-02-15T23:59:59.000Z

13

High-resolution heterodyne spectroscopy using a tunable quantum cascade laser around 3.5 THz  

E-Print Network [OSTI]

A frequency tunable terahertz heterodynespectrometer, based on a third-order distributed feedback quantum cascade laser as a local oscillator, has been demonstrated by measuring molecular spectral lines of methanol ...

Ren, Y.

14

High Spatial Resolution Thermal Imaging of Multiple Section Semiconductor Lasers Ali Shakouri*  

E-Print Network [OSTI]

and peak wavelength characteristics of active optoelectronic devices. In this paper we describe how for optoelectronic devices such as laser sources, switching/routing elements, and detectors. This is especially true (TE) coolers. However since their integration with optoelectronic devices is difficult [1

15

High-resolution adaptive optics scanning laser ophthalmoscope with multiple deformable mirrors  

DOE Patents [OSTI]

An adaptive optics scanning laser ophthalmoscopes is introduced to produce non-invasive views of the human retina. The use of dual deformable mirrors improved the dynamic range for correction of the wavefront aberrations compared with the use of the MEMS mirror alone, and improved the quality of the wavefront correction compared with the use of the bimorph mirror alone. The large-stroke bimorph deformable mirror improved the capability for axial sectioning with the confocal imaging system by providing an easier way to move the focus axially through different layers of the retina.

Chen, Diana C. (Fremont, CA); Olivier, Scot S. (Livermore, CA); Jones; Steven M. (Livermore, CA)

2010-02-23T23:59:59.000Z

16

Design, assembly, and testing of a high-resolution relay lens used for holography with operation at both doubled and tripled Nd:YAG laser wavelengths  

SciTech Connect (OSTI)

The design and assembly of a nine-element lens that achieves >2000 1p/mm resolution at a 355-nm wavelength (ultraviolet) has been completed. By adding a doublet to this lens system, operation at a 532-nm wavelength (green) with > 1100 1p/mm resolution is achieved. This lens is used with high-power laser light to record holograms of fast-moving ejecta particles from a shocked metal surface located inside a test package. Part of the lens and the entire test package are under vacuum with a 1-cm air gap separation. Holograms have been recorded with both doubled and tripled Nd:YAG laser light. The UV operation is very sensitive to the package window's tilt. If this window is tilted by more than 0.1 degrees, the green operation performs with better resolution than that of the UV operation. The setup and alignment are performed with green light, but the dynamic recording can be done with either UV light or green light. A resolution plate can be temporarily placed inside the test package so that a television microscope located beyond the hologram position can archive images of resolution patterns that prove that the calibration wires., interference filter, holographic plate, and relay lenses are in their correct positions. Part of this lens is under vacuum, at the point where the laser illumination passes through a focus. Alignment and tolerancing of this high-resolution lens are presented. Resolution variation across the 12-mm field of view and throughout the 5-mm depth of field is discussed for both wavelengths.

Sorenson, Danny S [Los Alamos National Laboratory; Pazuchanics, Peter D [Los Alamos National Laboratory; Malone, Robert M [NSTEC; Cox, Brian C [NSTEC; Frogget, Brent C [NSTEC; Kaufman, Morris I [NSTEC; Capelle, Gene A [NSTEC/SB; Grover, M [NSTEC/SB; Stevens, Gerald D [NSTEC/SB; Turley, William D [NSTEC/SB

2009-01-01T23:59:59.000Z

17

Lasers, Electron Beams and New Years Resolutions | Department...  

Broader source: Energy.gov (indexed) [DOE]

Lasers, Electron Beams and New Years Resolutions Lasers, Electron Beams and New Years Resolutions March 2, 2011 - 3:43pm Addthis Charles Rousseaux Charles Rousseaux Senior Writer,...

18

High-resolution measurements of the spatial and temporal evolution of megagauss magnetic fields created in intense short-pulse laser-plasma interactions  

SciTech Connect (OSTI)

A pump-probe polarimetric technique is demonstrated, which provides a complete, temporally and spatially resolved mapping of the megagauss magnetic fields generated in intense short-pulse laser-plasma interactions. A normally incident time-delayed probe pulse reflected from its critical surface undergoes a change in its ellipticity according to the magneto-optic Cotton-Mouton effect due to the azimuthal nature of the ambient self-generated megagauss magnetic fields. The temporal resolution of the magnetic field mapping is typically of the order of the pulsewidth, limited by the laser intensity contrast, whereas a spatial resolution of a few ?m is achieved by this optical technique. High-harmonics of the probe can be employed to penetrate deeper into the plasma to even near-solid densities. The spatial and temporal evolution of the megagauss magnetic fields at the target front as well as at the target rear are presented. The ?m-scale resolution of the magnetic field mapping provides valuable information on the filamentary instabilities at the target front, whereas probing the target rear mirrors the highly complex fast electron transport in intense laser-plasma interactions.

Chatterjee, Gourab, E-mail: gourab@tifr.res.in; Singh, Prashant Kumar; Adak, Amitava; Lad, Amit D.; Kumar, G. Ravindra, E-mail: grk@tifr.res.in [Tata Institute of Fundamental Research, 1 Homi Bhabha Road, Mumbai 400 005 (India)

2014-01-15T23:59:59.000Z

19

Performance predictions for a laser intensified thermal beam for use in high resolution Focused Ion Beam instruments  

E-Print Network [OSTI]

Photo-ionization of a laser-cooled and compressed atomic beam from a high-flux thermal source can be used to create a high-brightness ion beam for use in Focus Ion Beam (FIB) instruments. Here we show using calculations and Doppler cooling simulations that an atomic rubidium beam with a brightness of $2.1 \\times 10^7 A/(m^2\\,sr\\,eV)$ at a current of 1 nA can be created using a compact 5 cm long 2D magneto-optical compressor which is more than an order of magnitude better than the current state of the art Liquid Metal Ion Source.

Wouters, S H W; Notermans, R P M J W; Debernardi, N; Mutsaers, P H A; Luiten, O J; Vredenbregt, E J D

2014-01-01T23:59:59.000Z

20

High resolution time interval meter  

DOE Patents [OSTI]

Method and apparatus are provided for measuring the time interval between two events to a higher resolution than reliability available from conventional circuits and component. An internal clock pulse is provided at a frequency compatible with conventional component operating frequencies for reliable operation. Lumped constant delay circuits are provided for generating outputs at delay intervals corresponding to the desired high resolution. An initiation START pulse is input to generate first high resolution data. A termination STOP pulse is input to generate second high resolution data. Internal counters count at the low frequency internal clock pulse rate between the START and STOP pulses. The first and second high resolution data are logically combined to directly provide high resolution data to one counter and correct the count in the low resolution counter to obtain a high resolution time interval measurement.

Martin, A.D.

1986-05-09T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Investigation of a high spatial resolution method based on polar coordinate maximum entropy method for analyzing electron density fluctuation data measured by laser phase contrast  

SciTech Connect (OSTI)

Laser phase contrast is a powerful diagnostic method to determine the spatial distribution of electron density fluctuations in magnetically confined plasmas, although its applicability depends on magnetic field configurations. The spatial resolution of fluctuations is linked with the resolution of the propagation direction that is derived from the two-dimensional spectral analysis of the wavenumber for the fluctuations. The method was applied to fluctuation measurements in a compact helical system. In order to improve the resolution of the propagation direction with a relatively small number of data points, the maximum entropy method with polar coordinates was employed. A spatial resolution of the order of 1 cm was obtained, which is satisfactory in a plasma with a 20 cm minor radius.

Matsuo, K. [Fukuoka Institute of Technology, Fukuoka 811-0295 (Japan); Iguchi, H.; Okamura, S.; Matsuoka, K. [National Institute for Fusion Science, Toki 509-5292 (Japan)

2012-01-15T23:59:59.000Z

22

A new spectrometer design for the x-ray spectroscopy of laser-produced plasmas with high (sub-ns) time resolution  

SciTech Connect (OSTI)

This paper describes a new type of x-ray crystal spectrometer, which can be used in combination with gated x-ray detectors to obtain spectra from laser-produced plasmas with a high (sub-ns) time resolution. The spectrometer consists of a convex, spherically bent crystal, which images individual spectral lines as perfectly straight lines across multiple, sequentially gated, strip detectors. Since the Bragg-reflected rays are divergent, the distance between detector and crystal is arbitrary, so that this distance can be appropriately chosen to optimize the experimental arrangement with respect to the detector parameters. The spectrometer concept was verified in proof-of-principle experiments by imaging the L?{sub 1}- and L?{sub 2}-lines of tungsten, at 9.6735 and 9.96150 keV, from a micro-focus x-ray tube with a tungsten target onto a two-dimensional pixilated Pilatus detector, using a convex, spherically bent Si-422 crystal with a radius of curvature of 500 mm.

Bitter, M., E-mail: bitter@pppl.gov; Hill, K. W.; Efthimion, P. C.; Delgado-Aparicio, L.; Pablant, N. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lu, Jian [Department of Engineering, Chongqing University, Chongqing 400044 (China); Beiersdorfer, P.; Chen, Hui [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2014-11-15T23:59:59.000Z

23

Enhanced High Resolution RBS System  

SciTech Connect (OSTI)

Improvements in full spectrum resolution with the second NEC high resolution RBS system are summarized. Results for 50 A ring TiN/HfO films on Si yielding energy resolution on the order of 1 keV are also presented. Detector enhancements include improved pulse processing electronics, upgraded shielding for the MCP/RAE detector, and reduced noise generated from pumping. Energy resolution measurements on spectra front edge coupled with calculations using 0.4mStr solid angle show that beam energy spread at 400 KeV from the Pelletron registered accelerator is less than 100 eV. To improve user throughput, magnet control has been added to the automatic data collection. Depth profiles derived from experimental data are discussed. For the thin films profiled, depth resolutions were on the Angstrom level with the non-linear energy/channel conversions ranging from 100 to 200 eV.

Pollock, Thomas J.; Hass, James A.; Klody, George M. [National Electrostatics Corp., Middleton, Wisconsin, U. S. A. 53562-0310 (United States)

2011-06-01T23:59:59.000Z

24

High Resolution Timing with Low Resolution Clocks A Microsecond Resolution Timer for Sun Workstations  

E-Print Network [OSTI]

High Resolution Timing with Low Resolution Clocks and A Microsecond Resolution Timer for Sun for Sun 3 and Sun 4 workstations1. One can measure average service times without a high resolution clock?" 1. Introduction - Who Needs a Microsecond Clock Beginning with its Sun 3 workstations, Sun

Melvin, Stephen

25

advanced high resolution: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Resolution Imaging Spectrometer (MODIS) to calibrate advanced very high resolution radiometer Geosciences Websites Summary: Using Moderate Resolution Imaging Spectrometer (MODIS)...

26

High repetition rate fiber lasers  

E-Print Network [OSTI]

This thesis reports work in high repetition rate femtosecond fiber lasers. Driven by the applications including optical arbitrary waveform generation, high speed optical sampling, frequency metrology, and timing and frequency ...

Chen, Jian, Ph. D. Massachusetts Institute of Technology

2009-01-01T23:59:59.000Z

27

High resolution scintillation detector with semiconductor readout  

DOE Patents [OSTI]

A novel high resolution scintillation detector array for use in radiation imaging such as high resolution Positron Emission Tomography (PET) which comprises one or more parallelepiped crystals with at least one long surface of each crystal being in intimate contact with a semiconductor photodetector such that photons generated within each crystal by gamma radiation passing therethrough is detected by the photodetector paired therewith.

Levin, Craig S. (Santa Monica, CA); Hoffman, Edward J. (Los Angeles, CA)

2000-01-01T23:59:59.000Z

28

Laser Pointer System Intuitive Interaction for Large High-Res Displays  

E-Print Network [OSTI]

Laser Pointer System Intuitive Interaction for Large High-Res Displays LEDs Accelerometer Vibration Buttons Laser & LEDs Unlike conventional input devices like mouse and keyboard, laser pointers do that are displayed on large high-resolution screens. The laser pointer technology was developed in cooperation

Reiterer, Harald

29

Identifying chromatin interactions at high spatial resolution  

E-Print Network [OSTI]

This thesis presents two computational approaches for identifying chromatin interactions at high spatial resolution from ChIA-PET data. We introduce SPROUT which is a hierarchical probabilistic model that discovers high ...

Reeder, Christopher Campbell

2014-01-01T23:59:59.000Z

30

On the possibility of designing a high-resolution heterodyne spectrometer for near-IR range on the basis of a tunable diode laser  

SciTech Connect (OSTI)

The results of heterodyning of broadband radiation in the near-IR range are presented. A stabilised DFB laser was used as a local oscillator, while the role of a broadband radiation source was played by another DFB laser, excited by the pump current below its threshold value. A fibre-optical Y-coupler based on the single-mode silica fibre served as a diplexer. The radiation mixed in the singlemode fibre was incident on the photodetector, the role of which was played by a p - i - n photodiode. The signal from the photodiode was amplified by the preamplifier with the feedback resistance 240 k{Omega} and the bandwidth {approx}1 MHz and then digitised using a 16-digit ADC. The frequency scanning was implemented via the variation of the local oscillator frequency. The developed registration system provides the sensitivity {approx}1.4 % of the shot noise value at the acquisition time {approx}40 min.

Klimchuk, A Yu; Nadezhdinskii, Aleksandr I; Ponurovskii, Ya Ya; Shapovalov, Yu P; Rodin, A V

2012-03-31T23:59:59.000Z

31

arecibo high resolution: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

84 Using Moderate Resolution Imaging Spectrometer (MODIS) to calibrate advanced very high resolution radiometer Geosciences Websites Summary: Using Moderate Resolution Imaging...

32

Laser Fusion Energy The High Average Power  

E-Print Network [OSTI]

Laser Fusion Energy and The High Average Power Program John Sethian Naval Research Laboratory Dec for Inertial Fusion Energy with lasers, direct drive targets and solid wall chambers Lasers DPPSL (LLNL) Kr posters Snead Payne #12;Laser(s) Goals 1. Develop technologies that can meet the fusion energy

33

High-Resolution PET Detector. Final report  

SciTech Connect (OSTI)

The objective of this project was to develop an understanding of the limits of performance for a high resolution PET detector using an approach based on continuous scintillation crystals rather than pixelated crystals. The overall goal was to design a high-resolution detector, which requires both high spatial resolution and high sensitivity for 511 keV gammas. Continuous scintillation detectors (Anger cameras) have been used extensively for both single-photon and PET scanners, however, these instruments were based on NaI(Tl) scintillators using relatively large, individual photo-multipliers. In this project we investigated the potential of this type of detector technology to achieve higher spatial resolution through the use of improved scintillator materials and photo-sensors, and modification of the detector surface to optimize the light response function.We achieved an average spatial resolution of 3-mm for a 25-mm thick, LYSO continuous detector using a maximum likelihood position algorithm and shallow slots cut into the entrance surface.

Karp, Joel

2014-03-26T23:59:59.000Z

34

Supercomputers Fuel Global High-Resolution Climate Models  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Supercomputers Fuel Global High-Resolution Climate Models Supercomputers Fuel Global High-Resolution Climate Models Berkeley Lab Researcher Says Climate Science is Entering New...

35

Sandia National Laboratories: High-Resolution Computational Algorithms...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

WindHigh-Resolution Computational Algorithms for Simulating Offshore Wind Farms High-Resolution Computational Algorithms for Simulating Offshore Wind Farms This Sandia National...

36

Applications of High-Resolution Electrospray Ionization Mass...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

High-Resolution Electrospray Ionization Mass Spectrometry to Measurements of Average Oxygen to Carbon Ratios in Applications of High-Resolution Electrospray Ionization Mass...

37

Analysis of Rotational Structure in the High-Resolution Infrared...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Rotational Structure in the High-Resolution Infrared Spectrum and Assignment of Vibrational Fundamentals of Analysis of Rotational Structure in the High-Resolution Infrared...

38

Accelerated High-Resolution Differential Ion Mobility Separations...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

High-Resolution Differential Ion Mobility Separations Using Hydrogen. Accelerated High-Resolution Differential Ion Mobility Separations Using Hydrogen. Abstract: The resolving...

39

High Resolution and Low-Temperature Photoelectron Spectroscopy...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

High Resolution and Low-Temperature Photoelectron Spectroscopy of an Oxygen-Linked Fullerene Dimer Dianion: C120O2-. High Resolution and Low-Temperature Photoelectron Spectroscopy...

40

Coherent Vibrational Dynamics and High-Resolution Nonlinear Spectrosco...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Vibrational Dynamics and High-Resolution Nonlinear Spectroscopy: A Comparison with the AirDMSO Liquid Interface. Coherent Vibrational Dynamics and High-Resolution Nonlinear...

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

High precision, rapid laser hole drilling  

DOE Patents [OSTI]

A laser system produces a first laser beam for rapidly removing the bulk of material in an area to form a ragged hole. The laser system produces a second laser beam for accurately cleaning up the ragged hole so that the final hole has dimensions of high precision.

Chang, Jim J.; Friedman, Herbert W.; Comaskey, Brian J.

2013-04-02T23:59:59.000Z

42

High-power, high-intensity laser propagation and interactions  

SciTech Connect (OSTI)

This paper presents overviews of a number of processes and applications associated with high-power, high-intensity lasers, and their interactions. These processes and applications include: free electron lasers, backward Raman amplification, atmospheric propagation of laser pulses, laser driven acceleration, atmospheric lasing, and remote detection of radioactivity. The interrelated physical mechanisms in the various processes are discussed.

Sprangle, Phillip [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States); Electrical and Computer Engineering and Physics, University of Maryland, College Park, Maryland 20740 (United States); Hafizi, Bahman [Plasma Physics Division, Naval Research Laboratory, Washington, DC 20375 (United States)

2014-05-15T23:59:59.000Z

43

High-resolution spectroscopic probes of collisions and half-collisions  

SciTech Connect (OSTI)

Research in this program explores the dynamics of gas phase collisions and photodissociation by high-resolution laser spectroscopy. Simultaneous state and velocity detection frequently permits a determination of scalar or vector correlations among products. The correlated product distributions are always more informative, and often easier to interpret than the uncorrelated product state distributions. The authors have recently built an apparatus to record transient absorption spectra with 50 nS time resolution and 20 MHz frequency resolution using a single frequency Ti:sapphire laser. The photodissociation of NCCN and C{sub 2}H{sub 5}SCN at 193 nm is discussed.

Hall, G.E. [Brookhaven National Laboratory, Upton, NY (United States)

1993-12-01T23:59:59.000Z

44

High power laser perforating tools and systems  

DOE Patents [OSTI]

ystems devices and methods for the transmission of 1 kW or more of laser energy deep into the earth and for the suppression of associated nonlinear phenomena. Systems, devices and methods for the laser perforation of a borehole in the earth. These systems can deliver high power laser energy down a deep borehole, while maintaining the high power to perforate such boreholes.

Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F

2014-04-22T23:59:59.000Z

45

High resolution patterning of silica aerogels  

SciTech Connect (OSTI)

Three-dimensional metallic structures are fabricated with high spatial resolution in silica aerogels. In our method, silica hydrogels are prepared with a standard base-catalyzed route, and exchanged with an aqueous solution typically containing Ag{sup +} ions (1 M) and 2-propanol (0.2 M). The metal ions are reduced photolytically with a table-top ultraviolet lamp, or radiolytically, with a focused X-ray beam. We fabricated dots and lines as small as 30 x 70 {micro}m, protruding for several mm into the bulk of the materials. The hydrogels are eventually supercritically dried to yield aerogels, without any measurable change in the shape and spatial resolution of the lithographed structures. Transmission electron microscopy shows that illuminated regions are composed by Ag clusters with a size of several {micro}m, separated by thin layers of silica.

Bertino, M.F.; Hund, J.F.; Sosa, J.; Zhang, G.; Sotiriou-Leventis, C.; Leventis, N.; Tokuhiro, A.T.; Terry, J. (UMR-MUST); (IIT)

2008-10-30T23:59:59.000Z

46

Compact and highly efficient laser pump cavity  

DOE Patents [OSTI]

A new, compact, side-pumped laser pump cavity design which uses non-conventional optics for injection of laser-diode light into a laser pump chamber includes a plurality of elongated light concentration channels. In one embodiment, the light concentration channels are compound parabolic concentrators (CPC) which have very small exit apertures so that light will not escape from the pumping chamber and will be multiply reflected through the laser rod. This new design effectively traps the pump radiation inside the pump chamber that encloses the laser rod. It enables more uniform laser pumping and highly effective recycle of pump radiation, leading to significantly improved laser performance. This new design also effectively widens the acceptable radiation wavelength of the diodes, resulting in a more reliable laser performance with lower cost.

Chang, Jim J. (Dublin, CA); Bass, Isaac L. (Castro Valley, CA); Zapata, Luis E. (Livermore, CA)

1999-01-01T23:59:59.000Z

47

Characterization of spatially resolved high resolution x-ray spectrometers for high energy density physics and light source experiments  

SciTech Connect (OSTI)

A high resolution 1D imaging x-ray spectrometer concept comprising a spherically bent crystal and a 2D pixelated detector is being optimized for diagnostics of small sources such as high energy density physics (HEDP) and synchrotron radiation or x-ray free electron laser experiments. This instrument is used on tokamak experiments for Doppler measurements of ion temperature and plasma flow velocity profiles. Laboratory measurements demonstrate a resolving power, E/?E of order 10?000 and spatial resolution better than 10 ?m. Initial tests of the high resolution instrument on HEDP plasmas are being performed.

Hill, K. W., E-mail: khill@pppl.gov; Bitter, M.; Delgado-Aparacio, L.; Efthimion, P.; Pablant, N. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Lu, J. [Key Laboratory of Optoelectronic Technology and System of Ministry of Education, Chongqing University, Chongqing 400030 (China); Beiersdorfer, P.; Chen, H.; Magee, E. [Physics Division, Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

2014-11-15T23:59:59.000Z

48

Ultra-high resolution computed tomography imaging  

DOE Patents [OSTI]

A method for ultra-high resolution computed tomography imaging, comprising the steps of: focusing a high energy particle beam, for example x-rays or gamma-rays, onto a target object; acquiring a 2-dimensional projection data set representative of the target object; generating a corrected projection data set by applying a deconvolution algorithm, having an experimentally determined a transfer function, to the 2-dimensional data set; storing the corrected projection data set; incrementally rotating the target object through an angle of approximately 180.degree., and after each the incremental rotation, repeating the radiating, acquiring, generating and storing steps; and, after the rotating step, applying a cone-beam algorithm, for example a modified tomographic reconstruction algorithm, to the corrected projection data sets to generate a 3-dimensional image. The size of the spot focus of the beam is reduced to not greater than approximately 1 micron, and even to not greater than approximately 0.5 microns.

Paulus, Michael J. (Knoxville, TN); Sari-Sarraf, Hamed (Knoxville, TN); Tobin, Jr., Kenneth William (Harriman, TN); Gleason, Shaun S. (Knoxville, TN); Thomas, Jr., Clarence E. (Knoxville, TN)

2002-01-01T23:59:59.000Z

49

Tomography and High-Resolution Electron Microscopy Study of Surfaces...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Tomography and High-Resolution Electron Microscopy Study of Surfaces and Porosity in a Plate-Like ?-Al2O3. Tomography and High-Resolution Electron Microscopy Study of...

50

Communication: Spectroscopic phase and lineshapes in high-resolution...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Communication: Spectroscopic phase and lineshapes in high-resolution broadband sum frequency vibrational spectroscopy: Resolving Communication: Spectroscopic phase and lineshapes...

51

Merging high resolution geophysical and geochemical surveys to...  

Broader source: Energy.gov (indexed) [DOE]

hydrothermal alteration) - Geologic field work - OSU detailed mapping - Geophysics * Gravity - 1km grid collected * High resolution aeromagnetic - currently being collected *...

52

RESEARCH ARTICLE High-resolution climate change mapping with gridded  

E-Print Network [OSTI]

RESEARCH ARTICLE High-resolution climate change mapping with gridded historical climate products of climate research and adaptation efforts around the world. High-resolution gridded historical climate (GHC products to produce high-resolution temperature trend maps for the US Northeast from 1980 to 2009

Vermont, University of

53

Improved methods for high resolution electron microscopy  

SciTech Connect (OSTI)

Existing methods of making support films for high resolution transmission electron microscopy are investigated and novel methods are developed. Existing methods of fabricating fenestrated, metal reinforced specimen supports (microgrids) are evaluated for their potential to reduce beam induced movement of monolamellar crystals of C/sub 44/H/sub 90/ paraffin supported on thin carbon films. Improved methods of producing hydrophobic carbon films by vacuum evaporation, and improved methods of depositing well ordered monolamellar paraffin crystals on carbon films are developed. A novel technique for vacuum evaporation of metals is described which is used to reinforce microgrids. A technique is also developed to bond thin carbon films to microgrids with a polymer bonding agent. Unique biochemical methods are described to accomplish site specific covalent modification of membrane proteins. Protocols are given which covalently convert the carboxy terminus of papain cleaved bacteriorhodopsin to a free thiol. 53 refs., 19 figs., 1 tab.

Taylor, J.R.

1987-04-01T23:59:59.000Z

54

A ber-optic based calibration system for the High Resolution Fly's Eye  

E-Print Network [OSTI]

A ber-optic based calibration system for the High Resolution Fly's Eye cosmic ray observatory J, 800 Yale Blvd NE, Albuquerque, NM 87131-1156 Abstract This article describes the ber-optic based: Highest energy cosmic rays Fly's Eye Experiment HiRes YAG Laser Fiber-optics PMT PACS: 95.45.+i 95.85.Ls

55

High resolution non-contact interior profilometer  

DOE Patents [OSTI]

Apparatus and method for inspecting the interior surfaces of devices such as vessels having a single entry port. Laser energy is launched into the vessel, and the light reflected from the interior surfaces is interfered with reference laser energy to produce an interference pattern. This interference pattern is analyzed to reveal information about the condition of the interior surfaces of the device inspected.

Piltch, Martin S. (Los Alamos, NM); Patterson, R. Alan (Los Alamos, NM); Leeches, Gerald W. (Los Alamos, NM); Nierop, John Van (Largo, FL); Teti, John J. (Tampa, FL)

2001-01-01T23:59:59.000Z

56

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams  

E-Print Network [OSTI]

Submillimeter-resolution radiography of shielded structures with laser-accelerated electron beams (Received 24 March 2010; published 14 October 2010) We investigate the use of energetic electron beams beam (with energy >100 MeV) was generated by the process of laser-wakefield acceleration through

Umstadter, Donald

57

Apparatus for advancing a wellbore using high power laser energy  

DOE Patents [OSTI]

Delivering high power laser energy to form a borehole deep into the earth using laser energy. Down hole laser tools, laser systems and laser delivery techniques for advancement, workover and completion activities. A laser bottom hole assembly (LBHA) for the delivery of high power laser energy to the surfaces of a borehole, which assembly may have laser optics, a fluid path for debris removal and a mechanical means to remove earth.

Zediker, Mark S.; Land, Mark S.; Rinzler, Charles C.; Faircloth, Brian O.; Koblick, Yeshaya; Moxley, Joel F.

2014-09-02T23:59:59.000Z

58

High-performance laser processing using manipulated ultrafast laser pulses  

SciTech Connect (OSTI)

We employ manipulated ultrafast laser pulses to realize microprocessing with high-performance. Efficient microwelding of glass substrates by irradiation by a double-pulse train of ultrafast laser pulses is demonstrated. The bonding strength of two photostructurable glass substrates welded by double-pulse irradiation was evaluated to be 22.9 MPa, which is approximately 22% greater than that of a sample prepared by conventional irradiation by a single pulse train. Additionally, the fabrication of hollow microfluidic channels with a circular cross-sectional shape embedded in fused silica is realized by spatiotemporally focusing the ultrafast laser beam. We show both theoretically and experimentally that the spatiotemporal focusing of ultrafast laser beam allows for the creation of a three-dimensionally symmetric spherical peak intensity distribution at the focal spot.

Sugioka, Koji; Cheng Ya; Xu Zhizhan; Hanada, Yasutaka; Midorikawa, Katsumi [RIKEN - Advanced Science Institute, Wako, Saitama 351-0198 (Japan); State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences (China); RIKEN - Advanced Science Institute, Wako, Saitama 351-0198 (Japan)

2012-07-30T23:59:59.000Z

59

High-resolution ab initio three-dimensional x-ray diffraction microscopy  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

Coherent x-ray diffraction microscopy is a method of imaging nonperiodic isolated objects at resolutions limited, in principle, by only the wavelength and largest scattering angles recorded. We demonstrate x-ray diffraction imaging with high resolution in all three dimensions, as determined by a quantitative analysis of the reconstructed volume images. These images are retrieved from the three-dimensional diffraction data using no a priori knowledge about the shape or composition of the object, which has never before been demonstrated on a nonperiodic object. We also construct two-dimensional images of thick objects with greatly increased depth of focus (without loss of transverse spatial resolution). These methods can be used to image biological and materials science samples at high resolution with x-ray undulator radiation and establishes the techniques to be used in atomic-resolution ultrafast imaging at x-ray free-electron laser sources.

Chapman, Henry N.; Barty, Anton; Marchesini, Stefano; Noy, Aleksandr; Hau-Riege, Stefan P.; Cui, Congwu; Howells, Malcolm R.; Rosen, Rachel; He, Haifeng; Spence, John C.; Weierstall, Uwe; Beetz, Tobias; Jacobsen, Chris; Shapiro, David

2006-01-01T23:59:59.000Z

60

High vertical resolution crosswell seismic imaging  

DOE Patents [OSTI]

A method for producing high vertical resolution seismic images from crosswell data is disclosed. In accordance with one aspect of the disclosure, a set of vertically spaced, generally horizontally extending continuous layers and associated nodes are defined within a region between two boreholes. The specific number of nodes is selected such that the value of a particular characteristic of the subterranean region at each of the nodes is one which can be determined from the seismic data. Once values are established at the nodes, values of the particular characteristic are assigned to positions between the node points of each layer based on the values at node within that layer and without regard to the values at node points within any other layer. A seismic map is produced using the node values and the assigned values therebetween. In accordance with another aspect of the disclosure, an approximate model of the region is established using direct arrival traveltime data. Thereafter, the approximate model is adjusted using reflected arrival data. In accordance with still another aspect of the disclosure, correction is provided for well deviation. An associated technique which provides improvements in ray tracing is also disclosed.

Lazaratos, Spyridon K. (Houston, TX)

1999-12-07T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laser Seeding Yields High-Power Coherent Terahertz Radiation Laser Seeding Yields High-Power Coherent Terahertz Radiation Print Wednesday, 25 April 2007 00:00 Researchers at...

62

Dual wavelength laser damage testing for high energy lasers.  

SciTech Connect (OSTI)

As high energy laser systems evolve towards higher energies, fundamental material properties such as the laser-induced damage threshold (LIDT) of the optics limit the overall system performance. The Z-Backlighter Laser Facility at Sandia National Laboratories uses a pair of such kiljoule-class Nd:Phosphate Glass lasers for x-ray radiography of high energy density physics events on the Z-Accelerator. These two systems, the Z-Beamlet system operating at 527nm/ 1ns and the Z-Petawatt system operating at 1054nm/ 0.5ps, can be combined for some experimental applications. In these scenarios, dichroic beam combining optics and subsequent dual wavelength high reflectors will see a high fluence from combined simultaneous laser exposure and may even see lingering effects when used for pump-probe configurations. Only recently have researchers begun to explore such concerns, looking at individual and simultaneous exposures of optics to 1064 and third harmonic 355nm light from Nd:YAG [1]. However, to our knowledge, measurements of simultaneous and delayed dual wavelength damage thresholds on such optics have not been performed for exposure to 1054nm and its second harmonic light, especially when the pulses are of disparate pulse duration. The Z-Backlighter Facility has an instrumented damage tester setup to examine the issues of laser-induced damage thresholds in a variety of such situations [2] . Using this damage tester, we have measured the LIDT of dual wavelength high reflectors at 1054nm/0.5ps and 532nm/7ns, separately and spatially combined, both co-temporal and delayed, with single and multiple exposures. We found that the LIDT of the sample at 1054nm/0.5ps can be significantly lowered, from 1.32J/cm{sup 2} damage fluence with 1054/0.5ps only to 1.05 J/cm{sup 2} with the simultaneous presence of 532nm/7ns laser light at a fluence of 8.1 J/cm{sup 2}. This reduction of LIDT of the sample at 1054nm/0.5ps continues as the fluence of 532nm/7ns laser light simultaneously present increases. The reduction of LIDT does not occur when the 2 pulses are temporally separated. This paper will also present dual wavelength LIDT results of commercial dichroic beam-combining optics simultaneously exposed with laser light at 1054nm/2.5ns and 532nm/7ns.

Atherton, Briggs W.; Rambo, Patrick K.; Schwarz, Jens; Kimmel, Mark W.

2010-05-01T23:59:59.000Z

63

A High-Resolution Global Climate Simulation  

SciTech Connect (OSTI)

A major factor limiting the quality and usefulness of global climate models is the coarse spatial resolution of these models. Global climate models today are typically run at resolutions of {approx}300 km (or even coarser) meaning that the smallest features represented are 300 km across. As Figure 1 shows, this resolution does not allow adequate representation of small or even large topographic features (e.g. the Sierra Nevada mountains). As a result of this and other problems, coarse-resolution global models do not come close to accurately simulating climate on regional spatial scales (e.g. within California). Results on continental and larger sales are much more realistic. An important consequence of this inability to simulate regional climate is that global climate model results cannot be used as the basis of assessments of potential societal impacts of climate change (e.g. effects on agriculture in the Central Valley, on management of water resources, etc.).

Duffy, P B

2001-01-23T23:59:59.000Z

64

An Automated Platform for High-Resolution Tissue Imaging Using...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

entire image is acquired. The performance of the system is demonstrated by imaging rat brain tissue sections. High resolution mass analysis combined with MSMS experiments enabled...

65

Merging High Resolution Geophysical and Geochemical Surveys to...  

Open Energy Info (EERE)

Buttes, Oregon Geothermal Project Jump to: navigation, search Last modified on July 22, 2011. Project Title Merging High Resolution Geophysical and Geochemical Surveys to Reduce...

66

High-Resolution Desorption Electrospray Ionization Mass Spectrometry...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

between different mechanisms of chemical aging. Citation: Laskin J, A Laskin, PJ Roach, GW Slysz, GA Anderson, S Nizkorodov, DL Bones, and L Nguyen.2010."High-Resolution...

67

Mexico City Aerosol Analysis during MILAGRO using High Resolution...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2: Mexico City Aerosol Analysis during MILAGRO using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0). Part 2: Abstract: Submicron aerosol was analyzed during...

68

Mexico City Aerosol Analysis during MILAGRO using High Resolution...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1: Mexico City Aerosol Analysis during MILAGRO using High Resolution Aerosol Mass Spectrometry at the Urban Supersite (T0). Part 1: Abstract: Submicron aerosol was analyzed during...

69

High resolution, high rate x-ray spectrometer  

DOE Patents [OSTI]

It is an object of the invention to provide a pulse processing system for use with detected signals of a wide dynamic range which is capable of very high counting rates, with high throughput, with excellent energy resolution and a high signal-to-noise ratio. It is a further object to provide a pulse processing system wherein the fast channel resolving time is quite short and substantially independent of the energy of the detected signals. Another object is to provide a pulse processing system having a pile-up rejector circuit which will allow the maximum number of non-interfering pulses to be passed to the output. It is also an object of the invention to provide new methods for generating substantially symmetrically triangular pulses for use in both the main and fast channels of a pulse processing system.

Goulding, F.S.; Landis, D.A.

1983-07-14T23:59:59.000Z

70

High Energy Laser for Space Debris Removal  

SciTech Connect (OSTI)

The National Ignition Facility (NIF) and Photon Science Directorate at Lawrence Livermore National Laboratory (LLNL) has substantial relevant experience in the construction of high energy lasers, and more recently in the development of advanced high average power solid state lasers. We are currently developing new concepts for advanced solid state laser drivers for the Laser Inertial Fusion Energy (LIFE) application, and other high average power laser applications that could become central technologies for use in space debris removal. The debris population most readily addressed by our laser technology is that of 0.1-10 cm sized debris in low earth orbit (LEO). In this application, a ground based laser system would engage an orbiting target and slow it down by ablating material from its surface which leads to reentry into the atmosphere, as proposed by NASA's ORION Project. The ORION concept of operations (CONOPS) is also described in general terms by Phipps. Key aspects of this approach include the need for high irradiance on target, 10{sup 8} to 10{sup 9} W/cm{sup 2}, which favors short (i.e., picoseconds to nanoseconds) laser pulse durations and high energy per pulse ({approx} > 10 kJ). Due to the target's orbital velocity, the potential duration of engagement is only of order 100 seconds, so a high pulse repetition rate is also essential. The laser technology needed for this application did not exist when ORION was first proposed, but today, a unique combination of emerging technologies could create a path to enable deployment in the near future. Our concepts for the laser system architecture are an extension of what was developed for the National Ignition Facility (NIF), combined with high repetition rate laser technology developed for Inertial Fusion Energy (IFE), and heat capacity laser technology developed for military applications. The 'front-end' seed pulse generator would be fiber-optics based, and would generate a temporally, and spectrally tailored pulse designed for high transmission through the atmosphere, as well as efficient ablative coupling to the target. The main amplifier would use either diode-pumped or flashlamp-pumped solid state gain media, depending on budget constraints of the project. A continuously operating system would use the gas-cooled amplifier technology developed for Mercury, while a burst-mode option would use the heat capacity laser technology. The ground-based system that we propose is capable of rapid engagement of targets whose orbits cross over the site, with potential for kill on a single pass. Very little target mass is ablated per pulse so the potential to create additional hazardous orbiting debris is minimal. Our cost estimates range from $2500 to $5000 per J depending on choices for laser gain medium, amplifier pump source, and thermal management method. A flashlamp-pumped, Nd:glass heat-capacity laser operating in the burst mode would have costs at the lower end of this spectrum and would suffice to demonstrate the efficacy of this approach as a prototype system. A diode-pumped, gas-cooled laser would have higher costs but could be operated continuously, and might be desirable for more demanding mission needs. Maneuverability can be incorporated in the system design if the additional cost is deemed acceptable. The laser system would need to be coupled with a target pointing and tracking telescope with guide-star-like wavefront correction capability.

Barty, C; Caird, J; Erlandson, A; Beach, R; Rubenchik, A

2009-10-30T23:59:59.000Z

71

High-Pulse-Energy Ultrafast Laser for  

E-Print Network [OSTI]

High-Pulse-Energy Ultrafast Laser for Spectroscopy & Micromachining PROBLEM THIS TECHNOLOGY SOLVES. In addition to the OPO, a custom designed ultrafast pump source, provides high pulse energy (.res.hw.ac.uk Professor Derryck Reid (Principal Investigator) www.ultrafast.hw.ac.uk BENEFITS & APPLICATIONS: · High pulse

Painter, Kevin

72

Detection of Underground Marlpit Quarries Using High Resolution Seismic  

E-Print Network [OSTI]

Detection of Underground Marlpit Quarries Using High Resolution Seismic B. Piwakowski* (Ecole of high resolution reflection seismic for the detection and location of underground marlpit quarries of the geological structure, the results show that the detection of marlpit underground quarries, often considered

Boyer, Edmond

73

High resolution x-ray microscope  

SciTech Connect (OSTI)

The authors present x-ray images of grid meshes and biological material obtained using a microspot x-ray tube with a multilayer optic and a 92-element parabolic compound refractive lens (CRL) made of a plastic containing only hydrogen and carbon. Images obtained using this apparatus are compared with those using an area source with a spherical lens and a spherical lens with multilayer condenser. The authors found the best image quality using the multilayer condenser with a parabolic lens, compared to images with a spherical lens and without the multilayer optics. The resolution was measured using a 155-element parabolic CRL and a multilayer condenser with the microspot tube. The experiment demonstrates about 1.1 {mu}m resolution.

Gary, C. K.; Park, H.; Lombardo, L. W.; Piestrup, M. A.; Cremer, J. T.; Pantell, R. H.; Dudchik, Y. I. [Adelphi Technology, Inc. 981-B Industrial Road, San Carlos, California 94070 (United States); Department of Electrical Engineering, Stanford University, Stanford, California 94305 (United States); Institute of Applied Physics Problems, Kurchatova 7, Minsk 220064 (Belarus)

2007-04-30T23:59:59.000Z

74

Exploring electronic structure through high-resolution hard x...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Laboratory Modern high brilliance beamlines coupled with recent advances in hard-x-ray optics are establishing high-resolution hard x-ray spectroscopies as a powerful analytical...

75

assays high resolution: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Malbet 1995-09-14 31 High-resolution x-ray telescopes CERN Preprints Summary: High-energy astrophysics is a relatively young scientific field, made possible by space-borne...

76

analysing high resolution: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Malbet 1995-09-14 34 High-resolution x-ray telescopes CERN Preprints Summary: High-energy astrophysics is a relatively young scientific field, made possible by space-borne...

77

High density laser-driven target  

DOE Patents [OSTI]

A high density target for implosion by laser energy composed of a central quantity of fuel surrounded by a high-Z pusher shell with a low-Z ablator-pusher shell spaced therefrom forming a region filled with low-density material.

Lindl, John D. (San Ramon, CA)

1981-01-01T23:59:59.000Z

78

High Resolution, Ultrafast SFG Vibrational Spectroscopy | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickr FlickrGuidedCH2M HILLAdministration |BasicResolution, Ultrafast

79

High resolution data base for use with MAP  

SciTech Connect (OSTI)

A high resolution cartographic data base of thw World is available from the CIA. We obtained this data, extracted portions of the data, and produced cartographic files of varying resolutions. The resulting data files are of the proper format for use with MAP (2), our in-house cartographic plotting program.

Tapley, W.C.; Harris, D.B.

1987-05-05T23:59:59.000Z

80

High resolution image reconstruction with constrained, total-variation minimization  

E-Print Network [OSTI]

in computed tomography (CT), see for example [1], because it is possible to account for noise in the data the resolution is arbitrarily high, because the system resolution is still limited by the discrete data sampling of the volume and ideal conditions of perfect data consistency: g = Xf, (1) where g represents the projection

Kurien, Susan

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

High resolution linkage and association study of quantitative trait loci  

E-Print Network [OSTI]

As a large number of single nucleotide polymorphisms (SNPs) and microsatellite markers are available, high resolution mapping employing multiple markers or multiple allele markers is an important step to identify quantitative trait locus (QTL...

Jung, Jeesun

2005-11-01T23:59:59.000Z

82

Thin, Free-Standing Films For High Resolution Neutron Imaging.  

E-Print Network [OSTI]

??Thin, free-standing boro-phosphosilicate glass (BPSG) films were fabricated at PSU Nanofab to serve as prototype neutron converters for a proposed high resolution neutron imaging system… (more)

Trivelpiece, Cory

2010-01-01T23:59:59.000Z

83

Sapphire analyzers for high-resolution x-ray spectroscopy.  

SciTech Connect (OSTI)

We present a sapphire (Al{sub 2}O{sub 3}) analyzer for high-resolution X-ray spectroscopy with 31-meV energy resolution. The analyzer is designed for resonant inelastic X-ray scattering (RIXS) measurements at the CuK{sub a} absorption edge near 8990 eV. The performance of the analyzer is demonstrated by measuring phonon excitations in beryllium because of its known dynamical structure and high counting rates.

Yavas, H.; Alp, E.; Sinn, H.; Alatas, A.; Said, A.; Shvydko, Y.; Toellner, T.; Khachatryan, R.; Billinge, S.; Hasan, Z.; Sturhahn, W.; Michigan State Univ.; Princeton Univ.; DESY

2007-11-11T23:59:59.000Z

84

Phase conjugation of high energy lasers.  

SciTech Connect (OSTI)

In this report we explore claims that phase conjugation of high energy lasers by stimulated Brillouin scattering (SBS) can compensate optical aberrations associated with severely distorted laser amplifier media and aberrations induced by the atmosphere. The SBS media tested was a gas cell pressurized up to 300 psi with SF6 or Xe or both. The laser was a 10 Hz, 3J, Q-switched Nd:YAG with 25 ns wide pulses. Atmospheric aberrations were created with space heaters, helium jets and phase plates designed with a Kolmogorov turbulence spectrum characterized by a Fried parameter, ro , ranging from 0.6 - 6.0 mm. Phase conjugate tests in the laboratory were conducted without amplification. For the strongest aberrations, D/ro ~ 20, created by combining the space heaters with the phase plate, the Strehl ratio was degraded by a factor of ~50. Phase conjugation in SF6 restored the peak focusable intensity to about 30% of the original laser. Phase conjugate tests at the outdoor laser range were conducted with laser amplifiers providing gain in combination with the SBS cell. A large 600,000 BTU kerosene space heater was used to create turbulence along the beam path. An atmospheric structure factor of Cn2 = 5x10-13 m2/3 caused the illumination beam to expand to a diameter 250mm and overfill the receiver. The phase conjugate amplified return could successfully be targeted back onto glints 5mm in diameter. Use of a lenslet arrays to lower the peak focusable intensity in the SBS cell failed to produce a useful phase conjugate beam; The Strehl ratio was degraded with multiple random lobes instead of a single focus. I will review literature results which show how multiple beams can be coherently combined by SBS when a confocal reflecting geometry is used to focus the laser in the SBS cell.

Bliss, David Emery; Valley, Michael T.; Atherton, Briggs W.; Bigman, Verle; Boye, Lydia Ann; Broyles, Robin Scott; Kimmel, Mark W.; Law, Ryan J.; Yoder, James R.

2013-01-01T23:59:59.000Z

85

Coherent beam combiner for a high power laser  

DOE Patents [OSTI]

A phase conjugate laser mirror employing Brillouin-enhanced four wave mixing allows multiple independent laser apertures to be phase locked producing an array of diffraction-limited beams with no piston phase errors. The beam combiner has application in laser and optical systems requiring high average power, high pulse energy, and low beam divergence. A broad range of applications exist in laser systems for industrial processing, especially in the field of metal surface treatment and laser shot peening.

Dane, C. Brent (Livermore, CA); Hackel, Lloyd A. (Livermore, CA)

2002-01-01T23:59:59.000Z

86

Toward atomic resolution diffractive imaging of isolated molecules with x-ray free-electron lasers  

E-Print Network [OSTI]

We give a detailed account of the theoretical analysis and the experimental results of an x-ray-diffraction experiment on quantum-state selected and strongly laser-aligned gas-phase ensembles of the prototypical large asymmetric rotor molecule 2,5-diiodobenzonitrile, performed at the Linac Coherent Light Source [Phys. Rev. Lett. 112, 083002 (2014)]. This experiment is the first step toward coherent diffractive imaging of structures and structural dynamics of isolated molecules at atomic resolution, i. e., picometers and femtoseconds, using x-ray free-electron lasers.

Stern, Stephan; Filsinger, Frank; Rouzée, Arnaud; Rudenko, Artem; Johnsson, Per; Martin, Andrew V; Barty, Anton; Bostedt, Christoph; Bozek, John D; Coffee, Ryan N; Epp, Sascha; Erk, Benjamin; Foucar, Lutz; Hartmann, Robert; Kimmel, Nils; Kühnel, Kai-Uwe; Maurer, Jochen; Messerschmidt, Marc; Rudek, Benedikt; Starodub, Dmitri G; Thøgersen, Jan; Weidenspointner, Georg; White, Thomas A; Stapelfeldt, Henrik; Rolles, Daniel; Chapman, Henry N; Küpper, Jochen

2014-01-01T23:59:59.000Z

87

Trends in packaging of high power semiconductor laser bars  

SciTech Connect (OSTI)

Several different approaches to packaging high power diode laser bars for pumping solid state lasers or for direct diode laser applications are examined. The benefit and utility of each package is strongly dependent upon the fundamental optoelectronic properties of the individual diode laser bars. Factors which influence these properties are outlined and comparisons of packaging approaches for these materials are made.

Solarz, R.W.; Emanuel, M.A.; Skidmore, J.A.; Freitas, B.L.; Krupke, W.F.

1997-07-01T23:59:59.000Z

88

Phosphate glass useful in high energy lasers  

DOE Patents [OSTI]

In a high energy laser system utilizing phosphate laser glass components to amplify the laser beam, the laser system requires a generated laser beam having an emission bandwidth of less than 26 nm and the laser glass components consist essentially of (on an oxide composition basis) in mole percent: P{sub 2}O{sub 5}, 50--75; Al{sub 2}O{sub 3}, {gt}0--10; K{sub 2}O, {gt}0--30; MgO, 0--30; CaO, 0--30; Li{sub 2}O, 0--20; Na{sub 2}O, 0--20; Rb{sub 2}O, 0--20; Cs{sub 2}O, 0--20; BeO, 0--20; SrO, 0--20; BaO, 0--20; ZnO, 0--20; PbO, 0--20; B{sub 2}O{sub 3}, 0--10; Y{sub 2}O{sub 3}, 0--10; La{sub 2}O{sub 3}, 0--8; Ln{sub 2}O{sub 3}, 0.01--8; wherein the sum of MgO and CaO is >0--30; the sum of Li{sub 2}O, Na{sub 2}O, Rb{sub 2}O, and Cs{sub 2}O is 0--20; the sum of BeO, SrO, BaO, ZnO, and PbO is 0--20; the sum of B{sub 2}O{sub 3} and Y{sub 2}O{sub 3} is 0--10; and Ln{sub 2}O{sub 3} represents the sum of the oxides of active lasing lanthanides of atomic number 58--71. 21 figs.

Hayden, Yuiko T. (Clarks Summit, PA); Payne, Stephen A. (Castro Valley, CA); Hayden, Joseph S. (Clarks Summit, PA); Campbell, John H. (Livermore, CA); Aston, Mary Kay (Moscow, PA); Elder, Melanie L. (Dublin, CA)

1996-01-01T23:59:59.000Z

89

Phosphate glass useful in high energy lasers  

DOE Patents [OSTI]

In a high energy laser system utilizing phosphate laser glass components to amplify the laser beam, the laser system requires a generated laser beam having an emission bandwidth of less than 26 nm and the laser glass components consist essentially of (on an oxide composition basis) in mole percent: P{sub 2}O{sub 5}, 50--75; Al{sub 2}O{sub 3}, {gt}0--10; K{sub 2}O, {gt}0--30; MgO, 0--30; CaO, 0--30; Li{sub 2}O, 0--20; Na{sub 2}O, 0--20; Rb{sub 2}O, 0--20; Cs{sub 2}O, 0--20; BeO, 0--20; SrO, 0--20; BaO, 0--20; ZnO, 0--20; PbO, 0--20; B{sub 2}O{sub 3}, 0--10; Y{sub 2}O{sub 3}, 0--10; La{sub 2}O{sub 3}, 0--8; Ln{sub 2}O{sub 3}, 0.01--8; wherein the sum of MgO and CaO is >0--30; the sum of Li{sub 2}O, Na{sub 2}O, Rb{sub 2}O, and Cs{sub 2}O is 0--20; the sum of BeO, SrO, BaO, ZnO, and PbO is 0--20; the sum of B{sub 2}O{sub 3} and Y{sub 2}O{sub 3} is 0--10; and Ln{sub 2}O{sub 3} represents the sum of the oxides of active lasing lanthanides of atomic number 58--71. 21 figs.

Hayden, Y.T.; Payne, S.A.; Hayden, J.S.; Campbell, J.H.; Aston, M.K.; Elder, M.L.

1996-06-11T23:59:59.000Z

90

High resolution amorphous silicon radiation detectors  

DOE Patents [OSTI]

A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n-type, intrinsic, p-type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography. 18 figs.

Street, R.A.; Kaplan, S.N.; Perez-Mendez, V.

1992-05-26T23:59:59.000Z

91

High resolution amorphous silicon radiation detectors  

DOE Patents [OSTI]

A radiation detector employing amorphous Si:H cells in an array with each detector cell having at least three contiguous layers (n type, intrinsic, p type), positioned between two electrodes to which a bias voltage is applied. An energy conversion layer atop the silicon cells intercepts incident radiation and converts radiation energy to light energy of a wavelength to which the silicon cells are responsive. A read-out device, positioned proximate to each detector element in an array allows each such element to be interrogated independently to determine whether radiation has been detected in that cell. The energy conversion material may be a layer of luminescent material having a columnar structure. In one embodiment a column of luminescent material detects the passage therethrough of radiation to be detected and directs a light beam signal to an adjacent a-Si:H film so that detection may be confined to one or more such cells in the array. One or both electrodes may have a comb structure, and the teeth of each electrode comb may be interdigitated for capacitance reduction. The amorphous Si:H film may be replaced by an amorphous Si:Ge:H film in which up to 40 percent of the amorphous material is Ge. Two dimensional arrays may be used in X-ray imaging, CT scanning, crystallography, high energy physics beam tracking, nuclear medicine cameras and autoradiography.

Street, Robert A. (Palo Alto, CA); Kaplan, Selig N. (El Cerrito, CA); Perez-Mendez, Victor (Berkeley, CA)

1992-01-01T23:59:59.000Z

92

A High-resolution TOF Detector _ A Possible Way to Compete with a RICH Detector  

SciTech Connect (OSTI)

Using two identical 64-pixel Burle/Photonis MCP-PMTs to provide start and stop signals, they have achieved a timing resolution of {sigma}{sub Single{_}detector} {approx} 7.2 ps for N{sub pe} {approx} 50 photoelectrons (N{sub pe}) with a laser diode providing a 1 mm spot on the MCP window. The limiting resolution achieved was {sigma}{sub Single{_}detector} {approx} 5.0 ps for N{sub pe} {approx} 180, for which they estimate the MCP-PMT contribution of {sigma}{sub MCP-PMT} {approx} 4.5 ps. The electronics contribution is estimated as {sigma}{sub Electrons} = 3.42 ps. These results suggest that an ultra-high resolution TOF detector may become a reality at future experiments one day.

Va'vra, J; /SLAC; Ertley, C.; /Argonne; Leith, D.W.G.S.; Ratcliff, B.; Schwiening, J.; /SLAC

2008-07-25T23:59:59.000Z

93

Isotope specific resolution recovery image reconstruction in high resolution PET imaging  

SciTech Connect (OSTI)

Purpose: Measuring and incorporating a scanner-specific point spread function (PSF) within image reconstruction has been shown to improve spatial resolution in PET. However, due to the short half-life of clinically used isotopes, other long-lived isotopes not used in clinical practice are used to perform the PSF measurements. As such, non-optimal PSF models that do not correspond to those needed for the data to be reconstructed are used within resolution modeling (RM) image reconstruction, usually underestimating the true PSF owing to the difference in positron range. In high resolution brain and preclinical imaging, this effect is of particular importance since the PSFs become more positron range limited and isotope-specific PSFs can help maximize the performance benefit from using resolution recovery image reconstruction algorithms. Methods: In this work, the authors used a printing technique to simultaneously measure multiple point sources on the High Resolution Research Tomograph (HRRT), and the authors demonstrated the feasibility of deriving isotope-dependent system matrices from fluorine-18 and carbon-11 point sources. Furthermore, the authors evaluated the impact of incorporating them within RM image reconstruction, using carbon-11 phantom and clinical datasets on the HRRT. Results: The results obtained using these two isotopes illustrate that even small differences in positron range can result in different PSF maps, leading to further improvements in contrast recovery when used in image reconstruction. The difference is more pronounced in the centre of the field-of-view where the full width at half maximum (FWHM) from the positron range has a larger contribution to the overall FWHM compared to the edge where the parallax error dominates the overall FWHM. Conclusions: Based on the proposed methodology, measured isotope-specific and spatially variant PSFs can be reliably derived and used for improved spatial resolution and variance performance in resolution recovery image reconstruction. The benefits are expected to be more substantial for more energetic positron emitting isotopes such as Oxygen-15 and Rubidium-82.

Kotasidis, Fotis A. [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva, Switzerland and Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, M20 3LJ, Manchester (United Kingdom)] [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva, Switzerland and Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, M20 3LJ, Manchester (United Kingdom); Angelis, Georgios I. [Faculty of Health Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2006, Sydney (Australia)] [Faculty of Health Sciences, Brain and Mind Research Institute, University of Sydney, NSW 2006, Sydney (Australia); Anton-Rodriguez, Jose; Matthews, Julian C. [Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester M20 3LJ (United Kingdom)] [Wolfson Molecular Imaging Centre, MAHSC, University of Manchester, Manchester M20 3LJ (United Kingdom); Reader, Andrew J. [Montreal Neurological Institute, McGill University, Montreal QC H3A 2B4, Canada and Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas’ Hospital, London SE1 7EH (United Kingdom)] [Montreal Neurological Institute, McGill University, Montreal QC H3A 2B4, Canada and Department of Biomedical Engineering, Division of Imaging Sciences and Biomedical Engineering, King's College London, St. Thomas’ Hospital, London SE1 7EH (United Kingdom); Zaidi, Habib [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland) [Division of Nuclear Medicine and Molecular Imaging, Geneva University Hospital, CH-1211 Geneva (Switzerland); Geneva Neuroscience Centre, Geneva University, CH-1205 Geneva (Switzerland); Department of Nuclear Medicine and Molecular Imaging, University of Groningen, University Medical Center Groningen, PO Box 30 001, Groningen 9700 RB (Netherlands)

2014-05-15T23:59:59.000Z

94

Laser for high frequency modulated interferometry  

DOE Patents [OSTI]

A Stark-tuned laser operating in the 119 micron line of CH.sub.3 OH has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers. Provision is made for introducing a buffer gas into the resonator tube for increasing laser output power and its operating bandwidth.

Mansfield, Dennis K. (E. Windsor, NJ); Vocaturo, Michael (Columbus, NJ); Guttadora, Lawrence J. (Iselin, NJ)

1991-01-01T23:59:59.000Z

95

Laser for high frequency modulated interferometry  

DOE Patents [OSTI]

A Stark-tuned laser operating in the 119 micron line of CH[sub 3]OH has an output power of several tens of milliwatts at 30 Watts of pump power while exhibiting a doublet splitting of about ten MHz with the application of a Stark field on the order of 500 volts/cm. This output power allows for use of the laser in a multi-channel interferometer, while its high operating frequency permits the interferometer to measure rapid electron density changes in a pellet injected or otherwise fueled plasma such as encountered in magnetic fusion devices. The laser includes a long far-infrared (FIR) pyrex resonator tube disposed within a cylindrical water jacket and incorporating charged electrodes for applying the Stark field to a gas confined therein. With the electrodes located within the resonator tube, the resonator tube walls are cooled by a flowing coolant without electrical breakdown in the coolant liquid during application of the Stark field. Wall cooling allows for substantially increased FIR output powers. Provision is made for introducing a buffer gas into the resonator tube for increasing laser output power and its operating bandwidth. 10 figures.

Mansfield, D.K.; Vocaturo, M.; Guttadora, L.J.

1991-07-23T23:59:59.000Z

96

Lynx: A High-Resolution Synthetic Aperture Radar  

SciTech Connect (OSTI)

Lynx is a high resolution, synthetic aperture radar (SAR) that has been designed and built by Sandia National Laboratories in collaboration with General Atomics (GA). Although Lynx may be operated on a wide variety of manned and unmanned platforms, it is primarily intended to be fielded on unmanned aerial vehicles. In particular, it may be operated on the Predator, I-GNAT, or Prowler II platforms manufactured by GA Aeronautical Systems, Inc. The Lynx production weight is less than 120 lb. and has a slant range of 30 km (in 4 mm/hr rain). It has operator selectable resolution and is capable of 0.1 m resolution in spotlight mode and 0.3 m resolution in stripmap mode. In ground moving target indicator mode, the minimum detectable velocity is 6 knots with a minimum target cross-section of 10 dBsm. In coherent change detection mode, Lynx makes registered, complex image comparisons either of 0.1 m resolution (minimum) spotlight images or of 0.3 m resolution (minimum) strip images. The Lynx user interface features a view manager that allows it to pan and zoom like a video camera. Lynx was developed under corporate finding from GA and will be manufactured by GA for both military and commercial applications. The Lynx system architecture will be presented and some of its unique features will be described. Imagery at the finest resolutions in both spotlight and strip modes have been obtained and will also be presented.

Doerry, A.W.; Hensley, W.H.; Pace, F.; Stence, J.; Tsunoda, S.I.; Walker, B.C.; Woodring, M.

1999-03-08T23:59:59.000Z

97

High-Power Solid-State Lasers from a Laser Glass Perspective  

SciTech Connect (OSTI)

Advances in laser glass compositions and manufacturing have enabled a new class of high-energy/high-power (HEHP), petawatt (PW) and high-average-power (HAP) laser systems that are being used for fusion energy ignition demonstration, fundamental physics research and materials processing, respectively. The requirements for these three laser systems are different necessitating different glasses or groups of glasses. The manufacturing technology is now mature for melting, annealing, fabricating and finishing of laser glasses for all three applications. The laser glass properties of major importance for HEHP, PW and HAP applications are briefly reviewed and the compositions and properties of the most widely used commercial laser glasses summarized. Proposed advances in these three laser systems will require new glasses and new melting methods which are briefly discussed. The challenges presented by these laser systems will likely dominate the field of laser glass development over the next several decades.

Campbell, J H; Hayden, J S; Marker, A J

2010-12-17T23:59:59.000Z

98

Greenhouse Gas Laser Imaging Tomography Experiment (GreenLITE): Evaluation of a new method to look at high resolution spatial/temporal distributions of carbon over key sub km sites  

SciTech Connect (OSTI)

Recently a new laser based approach for measuring area with potential for producing 2D estimates of the concentration spatial distribution has been developed through a cooperative agreement with the National Energy and Technology Laboratory of the Department of Energy, Exelis Inc. and AER Inc. The new approach is based on a pair of continuous wave intensity modulated laser absorption spectrometer transceivers, combined with a series of retro reflectors located around the perimeter of the area being monitored. The main goal of this cooperative agreement is monitoring, reporting and verification for ground carbon capture and storage projects. The system was recently tested at the Zero Emission Research and Technology site in Bozeman, MT, with underground leak rates ranging from 0.1 – 0.3 metric ton per day (T/d), as well as a 0.8 T/d surface release. Over 200 hours of data were collected over a rectangular grid 180m x 200m between August 18th and September 9th. In addition, multiple days of in situ data were acquired for the same site, using a Licor gas analyzer systems. Initial comparisons between the laser-based system and the in situ agree very well. The system is designed to operate remotely and transmit the data via a 3G/4G connection along with weather data for the site. An all web-based system ingests the data, populates a database, performs the inversion to ppm CO2 using the Line-by-Line Radiative Transfer Model (LBLRTM), and displays plots and statistics for the retrieved data. We will present an overview of the GreenLITE measurement system, outline the retrieval and reconstruction approach, and discuss results from extensive field testing.

Dobler, Jeremy; Zaccheo, T. Scott; Blume, Nathan; Braun, Michael; Perninit, Timothy; McGregor, Doug; Botos, Chris; Dobeck, Laura

2015-01-01T23:59:59.000Z

99

High resolution collimator system for X-ray detector  

DOE Patents [OSTI]

High resolution in an X-ray computerized tomography (CT) inspection system is achieved by using a collimator/detector combination to limit the beam width of the X-ray beam incident on a detector element to the desired resolution width. In a detector such as a high pressure Xenon detector array, a narrow tapered collimator is provided above a wide detector element. The collimator slits have any desired width, as small as a few mils at the top, the slit width is easily controlled, and they are fabricated on standard machines. The slit length determines the slice thickness of the CT image.

Eberhard, Jeffrey W. (Schenectady, NY); Cain, Dallas E. (Scotia, NY)

1987-01-01T23:59:59.000Z

100

High energy femtosecond fiber laser at 1018 nm and high power Cherenkov radiation generation  

E-Print Network [OSTI]

Two novel laser systems for ultrafast applications have been designed and built. For the seeding of a high energy cryogenically cooled Yb:YLF laser, a novel 1018 nm fiber laser system is demonstrated. It produces >35 nJ ...

Yang, Hongyu, S.M. Massachusetts Institute of Technology

2014-01-01T23:59:59.000Z

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to obtain the most current and comprehensive results.


101

High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens  

E-Print Network [OSTI]

High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens M. S, representing the highest resolution subsurface thermography to date. Keywords: thermal imaging, high

102

Development of Superconducting High-Resolution Gamma-Ray Spectrometers for Nuclear Safeguards  

E-Print Network [OSTI]

Counting 2.4.3 High-Resolution Gamma Spectrometry 2.5coincidence counting and gamma spectrometry system (CANEGA)High-Resolution Gamma Spectrometry Isotopic correlation

Dreyer, Jonathan

2012-01-01T23:59:59.000Z

103

An Investigation of the Rotamers of Butadiene by High-Resolution...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Investigation of the Rotamers of Butadiene by High-Resolution Infrared Spectroscopy. An Investigation of the Rotamers of Butadiene by High-Resolution Infrared Spectroscopy....

104

Laser spectroscopy of hyperfine structure in highly-charged ions: a test of QED at high fields  

E-Print Network [OSTI]

An overview is presented of laser spectroscopy experiments with cold, trapped, highly-charged ions, which will be performed at the HITRAP facility at GSI in Darmstadt (Germany). These high-resolution measurements of ground state hyperfine splittings will be three orders of magnitude more precise than previous measurements. Moreover, from a comparison of measurements of the hyperfine splittings in hydrogen- and lithium-like ions of the same isotope, QED effects at high electromagnetic fields can be determined within a few percent. Several candidate ions suited for these laser spectroscopy studies are presented.

D. F. A. Winters; M. Vogel; D. M. Segal; R. C. Thompson; W. Noertershaeuser

2007-04-26T23:59:59.000Z

105

Unsupervised Feature Learning for High-Resolution Satellite Image Classification  

SciTech Connect (OSTI)

The rich data provided by high-resolution satellite imagery allow us to directly model geospatial neighborhoods by understanding their spatial and structural patterns. In this paper we explore an unsupervised feature learning approach to model geospatial neighborhoods for classification purposes. While pixel and object based classification approaches are widely used for satellite image analysis, often these approaches exploit the high-fidelity image data in a limited way. In this paper we extract low-level features to characterize the local neighborhood patterns. We exploit the unlabeled feature measurements in a novel way to learn a set of basis functions to derive new features. The derived sparse feature representation obtained by encoding the measured features in terms of the learned basis function set yields superior classification performance. We applied our technique on two challenging image datasets: ORNL dataset representing one-meter spatial resolution satellite imagery representing five land-use categories and, UCMERCED dataset consisting of 21 different categories representing sub-meter resolution overhead imagery. Our results are highly promising and, in the case of UCMERCED dataset we outperform the best results obtained for this dataset. We show that our feature extraction and learning methods are highly effective in developing a detection system that can be used to automatically scan large-scale high-resolution satellite imagery for detecting large-facility.

Cheriyadat, Anil M [ORNL

2013-01-01T23:59:59.000Z

106

High power laser workover and completion tools and systems  

DOE Patents [OSTI]

Workover and completion systems, devices and methods for utilizing 10 kW or more laser energy transmitted deep into the earth with the suppression of associated nonlinear phenomena. Systems and devices for the laser workover and completion of a borehole in the earth. These systems and devices can deliver high power laser energy down a deep borehole, while maintaining the high power to perform laser workover and completion operations in such boreholes deep within the earth.

Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F

2014-10-28T23:59:59.000Z

107

High-Resolution, Parallel Visualization of Turbomachinery Flowelds  

E-Print Network [OSTI]

High-Resolution, Parallel Visualization of Turbomachinery Flowelds Michael G. List , Mark G Turbomachinery post- and co-processing and visualization tools are under development. The result has been in the analysis of turbomachinery. It has always been the way of the CFD analyst to expand and resolve simulations

Cincinnati, University of

108

Greenland Observed at High Resolution by the Seasat Scatterometer  

E-Print Network [OSTI]

Greenland Observed at High Resolution by the Seasat Scatterometer D.G. Long', P.J. Hardin2, and RA to SASS data for the study of Greenland's ice sheet. We present a time series of the radar backscatter images over Greenland covering the time period July-September 1978. The images provide an island

Long, David G.

109

Absolute shape measurements using high-resolution optoelectronic holography methods  

E-Print Network [OSTI]

Absolute shape measurements using high- resolution optoelectronic holography methods Cosme Furlong optoelectronic holography (OEH) methodology is described. This description addresses apparatus and analysis-Optical Instrumentation Engineers. [S0091-3286(00)02601-5] Subject terms: CAD/CAE models; fiber optics; optoelectronic

Furlong, Cosme

110

A High-Resolution Single Nucleotide Polymorphism Genetic Map  

E-Print Network [OSTI]

A High-Resolution Single Nucleotide Polymorphism Genetic Map of the Mouse Genome Sagiv Shifman1 humans. Using more than 10,000 single nucleotide polymorphisms evenly spaced across the mouse genome, we nucleotide polymorphism genetic map of the mouse genome. PLoS Biol 4(12): e395. DOI: 10.1371/journal

Nachman, Michael

111

High-resolution terahertz atmospheric water vapor continuum measurements  

E-Print Network [OSTI]

High-resolution terahertz atmospheric water vapor continuum measurements David M. Slocum,* Thomas M such as pollution monitoring and the detection of energetic chemicals using remote sensing over long path lengths through the atmosphere. Although there has been much attention to atmospheric effects over narrow

Massachusetts at Lowell, University of

112

High-Resolution Triple Resonance Autoionization of Uranium Isotopes  

SciTech Connect (OSTI)

The near-threshold autoionization (AI) spectrum of uranium has been investigated by triple-resonance excitation with single-mode continuous lasers. Spectra were recorded over the first {approx}30 cm-1 above the first ionization limit at a resolution of 3x10-4 cm 1 using intermediate states with different J values (6, 7, 8) to assign AI level total angular momentum JAI = 5 to 9. Resonances with widths ranging from 8 MHz to 30 GHz were observed; the strongest ones have JAI = 9 and widths of {approx} 60 MHz. Hyperfine structures for 235U and isotope shifts for 234,235U have been measured in the two intermediate levels and in the final AI level for the most favorable excitation path. These measurements were performed using aqueous samples containing sub-milligram quantities of uranium at natural isotopic abundances, indicating the potential of this approach for trace isotope ratio determinations.

Schumann, Philipp G.; Wendt, K; Bushaw, Bruce A.

2005-11-01T23:59:59.000Z

113

High-resolution laser spectroscopy between 0.9 and 14.3 THz in a supersonic beam: Rydberg-Rydberg transitions of atomic Xe at intermediate n values  

SciTech Connect (OSTI)

A laser-based, pulsed, narrow-band source of submillimeter-wave radiation has been developed that is continuously tunable from 0.1 THz to 14.3 THz. The source is based on difference-frequency mixing in the nonlinear crystal trans-4{sup Prime }-(dimethylamino)-N-methyl-4-stilbazolium tosylate. By varying the pulse length, the bandwidth of the submillimeter-wave radiation can be adjusted between 85 MHz and 2.8 MHz. This new radiation source has been integrated in a vacuum-ultraviolet-submillimeter-ware double-resonance spectrometer, with which low-frequency transitions of atoms and molecules in supersonic beams can be detected mass-selectively by photoionization and time-of-flight mass spectrometry. The properties of the radiation source and spectrometer are demonstrated in a study of 33f Leftwards-Arrow nd Rydberg-Rydberg transitions in Xe with n in the range 16-31. The frequency calibration of the submillimeter-wave radiation was performed with an accuracy of 2.8 MHz. The narrowest lines observed experimentally have a full-width at half-maximum of {approx}3 MHz, which is sufficient to fully resolve the hyperfine structure of the Rydberg-Rydberg transitions of {sup 129}Xe and {sup 131}Xe. A total of 72 transitions were measured in the range between 0.937 THz and 14.245 THz and their frequencies are compared with frequencies calculated by multichannel quantum defect theory.

Haase, Christa; Agner, Josef A.; Merkt, Frederic [Laboratorium fuer Physikalische Chemie, ETH Zuerich, 8093 Zuerich (Switzerland)

2013-06-28T23:59:59.000Z

114

A low-cost, high-resolution, video-rate imaging optical radar  

SciTech Connect (OSTI)

Sandia National Laboratories has developed a unique type of portable low-cost range imaging optical radar (laser radar or LADAR). This innovative sensor is comprised of an active floodlight scene illuminator and an image intensified CCD camera receiver. It is a solid-state device (no moving parts) that offers significant size, performance, reliability, and simplicity advantages over other types of 3-D imaging sensors. This unique flash LADAR is based on low cost, commercially available hardware, and is well suited for many government and commercial uses. This paper presents an update of Sandia`s development of the Scannerless Range Imager technology and applications, and discusses the progress that has been made in evolving the sensor into a compact, low, cost, high-resolution, video rate Laser Dynamic Range Imager.

Sackos, J.T.; Nellums, R.O.; Lebien, S.M.; Diegert, C.F. [Sandia National Labs., Albuquerque, NM (United States); Grantham, J.W.; Monson, T. [Air Force Research Lab., Eglin AFB, FL (United States)

1998-04-01T23:59:59.000Z

115

Broadband high resolution X-ray spectral analyzer  

DOE Patents [OSTI]

A broad bandwidth high resolution x-ray fluorescence spectrometer has a performance that is superior in many ways to those currently available. It consists of an array of 4 large area microcalorimeters with 95% quantum efficiency at 6 keV and it produces x-ray spectra between 0.2 keV and 7 keV with an energy resolution of 7 to 10 eV. The resolution is obtained at input count rates per array element of 10 to 50 Hz in real-time, with analog pulse processing and thermal pile-up rejection. This performance cannot be matched by currently available x-ray spectrometers. The detectors are incorporated into a compact and portable cryogenic refrigerator system that is ready for use in many analytical spectroscopy applications as a tool for x-ray microanalysis or in research applications such as laboratory and astrophysical x-ray and particle spectroscopy.

Silver, Eric H. (Berkeley, CA); Legros, Mark (Berkeley, CA); Madden, Norm W. (Livermore, CA); Goulding, Fred (Lafayette, CA); Landis, Don (Pinole, CA)

1998-01-01T23:59:59.000Z

116

High-resolution ionization detector and array of such detectors  

DOE Patents [OSTI]

A high-resolution ionization detector and an array of such detectors are described which utilize a reference pattern of conductive or semiconductive material to form interaction, pervious and measurement regions in an ionization substrate of, for example, CdZnTe material. The ionization detector is a room temperature semiconductor radiation detector. Various geometries of such a detector and an array of such detectors produce room temperature operated gamma ray spectrometers with relatively high resolution. For example, a 1 cm.sup.3 detector is capable of measuring .sup.137 Cs 662 keV gamma rays with room temperature energy resolution approaching 2% at FWHM. Two major types of such detectors include a parallel strip semiconductor Frisch grid detector and the geometrically weighted trapezoid prism semiconductor Frisch grid detector. The geometrically weighted detector records room temperature (24.degree. C.) energy resolutions of 2.68% FWHM for .sup.137 Cs 662 keV gamma rays and 2.45% FWHM for .sup.60 Co 1.332 MeV gamma rays. The detectors perform well without any electronic pulse rejection, correction or compensation techniques. The devices operate at room temperature with simple commercially available NIM bin electronics and do not require special preamplifiers or cooling stages for good spectroscopic results.

McGregor, Douglas S. (Ypsilanti, MI); Rojeski, Ronald A. (Pleasanton, CA)

2001-01-16T23:59:59.000Z

117

Turbine component casting core with high resolution region  

DOE Patents [OSTI]

A hollow turbine engine component with complex internal features can include a first region and a second, high resolution region. The first region can be defined by a first ceramic core piece formed by any conventional process, such as by injection molding or transfer molding. The second region can be defined by a second ceramic core piece formed separately by a method effective to produce high resolution features, such as tomo lithographic molding. The first core piece and the second core piece can be joined by interlocking engagement that once subjected to an intermediate thermal heat treatment process thermally deform to form a three dimensional interlocking joint between the first and second core pieces by allowing thermal creep to irreversibly interlock the first and second core pieces together such that the joint becomes physically locked together providing joint stability through thermal processing.

Kamel, Ahmed; Merrill, Gary B.

2014-08-26T23:59:59.000Z

118

Space to Think: Large, High-Resolution Displays for Sensemaking  

SciTech Connect (OSTI)

Space supports human cognitive abilities in a myriad of ways. The note attached to the side of the monitor, the papers spread out on the desk, diagrams scrawled on a whiteboard, and even the keys left out on the counter are all examples of using space to recall, reveal relationships, and think. Technological advances have made it possible to construct large display environments in which space has real meaning. This paper examines how increased space affects the way displays are regarded and used within the context of the cognitively demanding task of sensemaking. A study was conducted observing analysts using a prototype large, high-resolution display to solve an analytic problem. This paper reports on the results of this study and suggests a number of potential design criteria for future sensemaking tools developed for large, high-resolution displays.

Andrews, Christopher P.; Endert, Alexander; North, Chris

2010-05-05T23:59:59.000Z

119

High resolution reservoir geological modelling using outcrop information  

SciTech Connect (OSTI)

This is China`s first case study of high resolution reservoir geological modelling using outcrop information. The key of the modelling process is to build a prototype model and using the model as a geological knowledge bank. Outcrop information used in geological modelling including seven aspects: (1) Determining the reservoir framework pattern by sedimentary depositional system and facies analysis; (2) Horizontal correlation based on the lower and higher stand duration of the paleo-lake level; (3) Determining the model`s direction based on the paleocurrent statistics; (4) Estimating the sandbody communication by photomosaic and profiles; (6) Estimating reservoir properties distribution within sandbody by lithofacies analysis; and (7) Building the reservoir model in sandbody scale by architectural element analysis and 3-D sampling. A high resolution reservoir geological model of Youshashan oil field has been built by using this method.

Zhang Changmin; Lin Kexiang; Liu Huaibo [Jianghan Petroleum Institute, Hubei (China)] [and others

1997-08-01T23:59:59.000Z

120

High Spatial Resolution Observations of Loops in the Solar Corona  

E-Print Network [OSTI]

Understanding how the solar corona is structured is of fundamental importance to determining how the Sun's upper atmosphere is heated to high temperatures. Recent spectroscopic studies have suggested that an instrument with a spatial resolution of 200km or better is necessary to resolve coronal loops. The High Resolution Coronal Imager (Hi-C) achieved this performance on a rocket flight in July 2012. We use Hi-C data to measure the Gaussian widths of 91 loops observed in the solar corona and find a distribution that peaks at about 270km. We also use Atmospheric Imaging Assembly (AIA) data for a subset of 79 of these loops and find that their temperature distributions are narrow. These observations provide further evidence that loops in the solar corona are structured at a scale of several hundred kilometers, well above the spatial scale of proposed physical mechanisms.

Brooks, David H; Ugarte-Urra, Ignacio; Winebarger, Amy R

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

HIGH SPATIAL RESOLUTION OBSERVATIONS OF LOOPS IN THE SOLAR CORONA  

SciTech Connect (OSTI)

Understanding how the solar corona is structured is of fundamental importance to determine how the Sun's upper atmosphere is heated to high temperatures. Recent spectroscopic studies have suggested that an instrument with a spatial resolution of 200 km or better is necessary to resolve coronal loops. The High Resolution Coronal Imager (Hi-C) achieved this performance on a rocket flight in 2012 July. We use Hi-C data to measure the Gaussian widths of 91 loops observed in the solar corona and find a distribution that peaks at about 270 km. We also use Atmospheric Imaging Assembly data for a subset of these loops and find temperature distributions that are generally very narrow. These observations provide further evidence that loops in the solar corona are often structured at a scale of several hundred kilometers, well above the spatial scale of many proposed physical mechanisms.

Brooks, David H.; Ugarte-Urra, Ignacio [College of Science, George Mason University, 4400 University Drive, Fairfax, VA 22030 (United States); Warren, Harry P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375 (United States); Winebarger, Amy R. [NASA Marshall Space Flight Center, ZP 13, Huntsville, AL 35812 (United States)

2013-08-01T23:59:59.000Z

122

Future scientific applications for high-energy lasers  

SciTech Connect (OSTI)

This report discusses future applications for high-energy lasers in the areas of astrophysics and space physics; hydrodynamics; material properties; plasma physics; radiation sources; and radiative properties.

Lee, R.W. [comp.

1994-08-01T23:59:59.000Z

123

A high resolution cavity BPM for the CLIC Test Facility  

E-Print Network [OSTI]

In frame of the development of a high resolution BPM system for the CLIC Main Linac we present the design of a cavity BPM prototype. It consists of a waveguide loaded dipole mode resonator and a monopole mode reference cavity, both operating at 15 GHz, to be compatible with the bunch frequencies at the CLIC Test Facility. Requirements, design concept, numerical analysis, and practical considerations are discussed.

Chritin, N; Soby, L; Lunin, A; Solyak, N; Wendt, M; Yakovlev, V

2012-01-01T23:59:59.000Z

124

The investigation of high intensity laser driven micro neutron sources  

E-Print Network [OSTI]

, access to high temperature states of mat- ter capable of thermonuclear fusion and/or the effi- cientThe investigation of high intensity laser driven micro neutron sources for fusion materials. The application of fast pulse, high intensity lasers to drive low cost DT point neutron sources for fusion

Ghoniem, Nasr M.

125

High energy resolution, high angular acceptance crystal monochromator  

DOE Patents [OSTI]

A 4-bounce dispersive crystal monochromator reduces the bandpass of synchrotron radiation to a 10-50 meV range without sacrificing angular acceptance. The monochromator includes the combination of an asymmetrical channel-cut single crystal of lower order reflection and a symmetrical channel-cut single crystal of higher order reflection in a nested geometric configuration. In the disclosed embodiment, a highly asymmetrically cut (.alpha.=20) outer silicon crystal (4 2 2) with low order reflection is combined with a symmetrically cut inner silicon crystal (10 6 4) with high order reflection to condition a hard x-ray component (5-30 keV) of synchrotron radiation down to the .mu.eV-neV level. Each of the crystals is coupled to the combination of a positioning inchworm and angle encoder via a respective rotation stage for accurate relative positioning of the crystals and precise energy tuning of the monochromator.

Alp, Ercan E. (Bolingbrook, IL); Mooney, Timothy M. (Westmont, IL); Toellner, Thomas (Green Bay, WI)

1996-06-04T23:59:59.000Z

126

High power solid state laser modulator  

DOE Patents [OSTI]

A multi-stage magnetic modulator provides a pulse train of .+-.40 kV electrical pulses at a 5-7 kHz repetition rate to a metal vapor laser. A fractional turn transformer steps up the voltage by a factor of 80 to 1 and magnetic pulse compression is used to reduce the pulse width of the pulse train. The transformer is fabricated utilizing a rod and plate stack type of construction to achieve a high packing factor. The pulses are controlled by an SCR stack where a plurality of SCRs are electrically connected in parallel, each SCR electrically connected to a saturable inductor, all saturable inductors being wound on the same core of magnetic material for enhanced power handling characteristics.

Birx, Daniel L.; Ball, Don G.; Cook, Edward G.

2004-04-27T23:59:59.000Z

127

ON THE IMPACT OF SUPER RESOLUTION WSR-88D DOPPLER RADAR DATA ASSIMILATION ON HIGH RESOLUTION NUMERICAL MODEL FORECASTS  

SciTech Connect (OSTI)

Assimilation of radar velocity and precipitation fields into high-resolution model simulations can improve precipitation forecasts with decreased 'spin-up' time and improve short-term simulation of boundary layer winds (Benjamin, 2004 & 2007; Xiao, 2008) which is critical to improving plume transport forecasts. Accurate description of wind and turbulence fields is essential to useful atmospheric transport and dispersion results, and any improvement in the accuracy of these fields will make consequence assessment more valuable during both routine operation as well as potential emergency situations. During 2008, the United States National Weather Service (NWS) radars implemented a significant upgrade which increased the real-time level II data resolution to 8 times their previous 'legacy' resolution, from 1 km range gate and 1.0 degree azimuthal resolution to 'super resolution' 250 m range gate and 0.5 degree azimuthal resolution (Fig 1). These radar observations provide reflectivity, velocity and returned power spectra measurements at a range of up to 300 km (460 km for reflectivity) at a frequency of 4-5 minutes and yield up to 13.5 million point observations per level in super-resolution mode. The migration of National Weather Service (NWS) WSR-88D radars to super resolution is expected to improve warning lead times by detecting small scale features sooner with increased reliability; however, current operational mesoscale model domains utilize grid spacing several times larger than the legacy data resolution, and therefore the added resolution of radar data is not fully exploited. The assimilation of super resolution reflectivity and velocity data into high resolution numerical weather model forecasts where grid spacing is comparable to the radar data resolution is investigated here to determine the impact of the improved data resolution on model predictions.

Chiswell, S

2009-01-11T23:59:59.000Z

128

Application Of High-Resolution Thermal Infrared Sensors For Geothermal...  

Open Energy Info (EERE)

the distribution surrounding the most active geothermal features. The higher spectralspatial resolution SEBASS data were used to validate the lower spectralspatial resolution...

129

High-resolution NMR process analyzer for oxygenates in gasoline  

SciTech Connect (OSTI)

We report a high-resolution 42-MHz[sup 1]HFT-NMR instrument that is suitable for use as a process analyzer and demonstrate its use in the determination of methyl tert-butyl ether (MTBE) in a flowing stream of gasoline. This spectrometer is based on a 55-kg permanent magnet with essentially no fringe field. A spectral resolution of 3 Hz was typically obtained for spinning samples, and this performance was only slightly degraded with flowing samples. We report a procedure for magnet drift compensation using a software procedure rather than a field-frequency lock channel. This procedure allowed signal averaging without loss of resolution. Regulatory changes to be implemented in the near future have created a need for the development of methods for the determination of MTBE and other oxygenates in reformulated gasolines. Existing methods employing gas chromatography are not fast enough for process control of a gasoline blender and suffer from other limitations. This study demonstrates that process analysis NMR is well-suited to the determination of MTBE in a simulated gasoline blender. The detection limit of 0.5 vol % MTBE was obtained with a measurement time of 1 min. The absolute standard deviation of independent determinations was 0.17% when the MTBE concentration was 10%, a nominal value. Preliminary results also suggest that the method may be applicable to gasolines containing mixtures of oxygenate additives as well as the measurement of aromatic and olefinic hydrogens. 33 refs., 9 figs.

Skloss, T.W.; Kim, A.J.; Haw, J.F. (Texas A M Univ., College Station, TX (United States))

1994-02-15T23:59:59.000Z

130

High-resolution SIMS depth profiling of nanolayers.  

SciTech Connect (OSTI)

Although the fundamental physical limits for depth resolution of secondary ion mass spectrometry are well understood in theory, the experimental work to achieve and demonstrate them is still ongoing. We report results of high-resolution TOF SIMS (time-of-flight secondary ion mass spectrometry) depth profiling experiments on a nanolayered structure, a stack of 16 alternating MgO and ZnO {approx}5.5 nm layers grown on a Si substrate by atomic layer deposition. The measurements were performed using a newly developed approach implementing a low-energy direct current normally incident Ar{sup +} ion beam for ion milling (250 eV and 500 eV energy), in combination with a pulsed 5 keV Ar{sup +} ion beam at 60{sup o} incidence for TOF SIMS analysis. By this optimized arrangement, a noticeably improved version of the dual-beam (DB) approach to TOF SIMS depth profiling is introduced, which can be dubbed gentleDB. The mixing-roughness-information model was applied to detailed analysis of experimental results. It revealed that the gentleDB approach allows ultimate depth resolution by confining the ion beam mixing length to about two monolayers. This corresponds to the escape depth of secondary ions, the fundamental depth resolution limitation in SIMS. Other parameters deduced from the measured depth profiles indicated that a single layer thickness is equal to 6 nm so that the 'flat' layer thickness d is 3 nm and the interfacial roughness {sigma} is 1.5 nm, thus yielding d + 2{sigma} = 6 nm. We have demonstrated that gentleDB TOF SIMS depth profiling with noble gas ion beams is capable of revealing the structural features of a stack of nanolayers, resolving its original surface and estimating the roughness of interlayer interfaces, information which is difficult to obtain by traditional approaches.

Baryshev, S. V.; Zinovev, A. V.; Tripa, C. E.; Pellin, M. J.; Peng, Q.; Elam, J. W.; Veryovkin, I. V. (Energy Systems); ( MSD)

2012-10-15T23:59:59.000Z

131

High-resolution radio observations of X-ray binaries  

E-Print Network [OSTI]

I present an overview of important results obtained using high-resolution very long baseline interferometry (VLBI) observations of X-ray binary systems. These results derive from both astrometric observations and resolved imaging of sources, from black holes to neutron star and even white dwarf systems. I outline a number of upcoming developments in instrumentation, both new facilities and ongoing upgrades to existing VLBI instruments, and I conclude by identifying a number of important areas of investigation where VLBI will be crucial in advancing our understanding of X-ray binaries.

James Miller-Jones

2008-09-15T23:59:59.000Z

132

High resolution coherent diffractive imaging with a table-top extreme ultraviolet source  

SciTech Connect (OSTI)

We demonstrate a resolution of 45?nm with a sample size down to 3??m × 3??m is achieved in a short exposure time of 2?s, from the diffraction pattern generated by a table-top high harmonic source at around 30?nm. By using a narrow-bandwidth focusing mirror, the diffraction pattern's quality is improved and the required exposure time is significantly reduced. In order to obtain a high quality of the reconstructed image, the ratio of the beam size to the sample size and the curvature of the focused beam need to be considered in the reconstruction process. This new experimental scheme is very promising for imaging sub-10?nm scale objects with a table-top source based on a small inexpensive femtosecond laser system.

Vu Le, Hoang, E-mail: vuhoangle@swin.edu.au; Ba Dinh, Khuong; Hannaford, Peter; Van Dao, Lap [Centre for Quantum and Optical Science, Swinburne University of Technology, Melbourne 3122 (Australia)

2014-11-07T23:59:59.000Z

133

Laser device  

DOE Patents [OSTI]

A laser device includes a target position, an optical component separated a distance J from the target position, and a laser energy source separated a distance H from the optical component, distance H being greater than distance J. A laser source manipulation mechanism exhibits a mechanical resolution of positioning the laser source. The mechanical resolution is less than a spatial resolution of laser energy at the target position as directed through the optical component. A vertical and a lateral index that intersect at an origin can be defined for the optical component. The manipulation mechanism can auto align laser aim through the origin during laser source motion. The laser source manipulation mechanism can include a mechanical index. The mechanical index can include a pivot point for laser source lateral motion and a reference point for laser source vertical motion. The target position can be located within an adverse environment including at least one of a high magnetic field, a vacuum system, a high pressure system, and a hazardous zone. The laser source and an electro-mechanical part of the manipulation mechanism can be located outside the adverse environment. The manipulation mechanism can include a Peaucellier linkage.

Scott, Jill R. (Idaho Falls, ID); Tremblay, Paul L. (Idaho Falls, ID)

2007-07-10T23:59:59.000Z

134

Microsoft PowerPoint - High Gradient Inverse Free Electron Laser...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Hi h G di t Hi h i High Gradient High energy gain Inverse Free Electron Laser at BNL P. Musumeci UCLA Department of Physics and Astronomy ATF user meeting April 2-3 2009 Outline...

135

Sub 400 nm spatial resolution extreme ultraviolet holography with a table top laser  

E-Print Network [OSTI]

. J. E. Trebes, S. B. Brown, E. M. Campbell, D. L. Matthews, D. G. Nilson, G. F. Stone, and D. A Society of America OCIS codes: (090.0090) Holography; (100.2960) Image analysis References and Links 1. D, C. Jacobsen, E. Anderson, M. R. Howells, and D. P. Kern, "High resolution imaging by Fourier

Rocca, Jorge J.

136

High energy XeBr electric discharge laser  

DOE Patents [OSTI]

A high energy XeBr laser for producing coherent radiation at 282 nm. The XeBr laser utilizes an electric discharge as the excitation source to minimize formation of molecular ions thereby minimizing absorption of laser radiation by the active medium. Additionally, HBr is used as the halogen donor which undergoes harpooning reactions with Xe.sub.M * to form XeBr*.

Sze, Robert C. (Santa Fe, NM); Scott, Peter B. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

137

Laser-Plasma Acceleration of Electrons and Plasma Diagnostics at High Laser Fields  

E-Print Network [OSTI]

Laser-Plasma Acceleration of Electrons and Plasma Diagnostics at High Laser Fields Mike Downer-GeV electron energies. I will review initial results in this regime, and discuss plasma diagnostics needed.5395) Plasma diagnostics 1. Introduction 30 years ago, Tajima and Dawson proposed the idea of accelerating

Shvets, Gennady

138

Analysis of the rotational structure in the high-resolution infrared...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

rotational structure in the high-resolution infrared spectra of cis,cis- and trans,trans-1,4-difluorobutadiene-1 Analysis of the rotational structure in the high-resolution...

139

Analysis of the Rotational Structure in the High-Resolution Infrared...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Rotational Structure in the High-Resolution Infrared Spectrum of trans-Hexatriene-1-13C1; a Semiexperimental Analysis of the Rotational Structure in the High-Resolution Infrared...

140

E-Print Network 3.0 - alto high-resolution search Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

. CARMENES, Calar Alto high-Resolution search for M dwarfs with Exo-earths with a Near-infrared Echelle... -velocity noise. As a high-resolution ... Source: Gutirrez,...

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Target isolation system, high power laser and laser peening method and system using same  

DOE Patents [OSTI]

A system for applying a laser beam to work pieces, includes a laser system producing a high power output beam. Target delivery optics are arranged to deliver the output beam to a target work piece. A relay telescope having a telescope focal point is placed in the beam path between the laser system and the target delivery optics. The relay telescope relays an image between an image location near the output of the laser system and an image location near the target delivery optics. A baffle is placed at the telescope focal point between the target delivery optics and the laser system to block reflections from the target in the target delivery optics from returning to the laser system and causing damage.

Dane, C. Brent (Livermore, CA); Hackel, Lloyd A. (Livermore, CA); Harris, Fritz (Rocklin, CA)

2007-11-06T23:59:59.000Z

142

High-level waste issues and resolutions document  

SciTech Connect (OSTI)

The High-Level Waste (HLW) Issues and Resolutions Document recognizes US Department of Energy (DOE) complex-wide HLW issues and offers potential corrective actions for resolving these issues. Westinghouse Management and Operations (M&O) Contractors are effectively managing HLW for the Department of Energy at four sites: Idaho National Engineering Laboratory (INEL), Savannah River Site (SRS), West Valley Demonstration Project (WVDP), and Hanford Reservation. Each site is at varying stages of processing HLW into a more manageable form. This HLW Issues and Resolutions Document identifies five primary issues that must be resolved in order to reach the long-term objective of HLW repository disposal. As the current M&O contractor at DOE`s most difficult waste problem sites, Westinghouse recognizes that they have the responsibility to help solve some of the complexes` HLW problems in a cost effective manner by encouraging the M&Os to work together by sharing expertise, eliminating duplicate efforts, and sharing best practices. Pending an action plan, Westinghouse M&Os will take the initiative on those corrective actions identified as the responsibility of an M&O. This document captures issues important to the management of HLW. The proposed resolutions contained within this document set the framework for the M&Os and DOE work cooperatively to develop an action plan to solve some of the major complex-wide problems. Dialogue will continue between the M&Os, DOE, and other regulatory agencies to work jointly toward the goal of storing, treating, and immobilizing HLW for disposal in an environmentally sound, safe, and cost effective manner.

Not Available

1994-05-01T23:59:59.000Z

143

Application of soft X-ray lasers for probing high density plasmas  

SciTech Connect (OSTI)

The reliability and characteristics of collisionally pumped soft x-ray lasers make them ideal for a wide variety of plasma diagnostics. These systems now operate over a wavelength range extending from 35 to 400 {Angstrom} and have output energies as high as 10 mJ in 150 ps pulses. The beam divergence of these lasers is less than 15 mrad and they have a typical linewidth of {Delta}{lambda}/{lambda} {approximately} 10{sup -4} making them the brightest xuv sources available. In this paper we will describe the use of x-ray lasers to probe high density plasmas using a variety of diagnostic techniques. Using an x-ray laser and a multilayer mirror imaging system we have studied hydrodynamic imprinting of laser speckle pattern on directly driven thin foils with 1-2 {mu}m spatial resolution. Taking advantage of recently developed multilayer beamsplitters we have constructed and used a Mach-Zehnder interferometer operating at 155 {Angstrom} to probe 1-3 mm size laser produced plasmas with peak electron densities of 4 x 10{sup 21} cm{sup -3}. A comparison of our results with computer simulations will be presented.

Da Silva, L.B.; Barbee, T.W. Jr.; Cauble, R. [and others

1996-08-01T23:59:59.000Z

144

Final report: high resolution lensless 3D imaging of nanostructures with coherent x-rays  

SciTech Connect (OSTI)

Final report on the project "High resolution lensless 3D imaging of nanostructures with coherent x-rays"

Jacobsen, Chris

2014-12-07T23:59:59.000Z

145

High-resolution X-ray spectroscopy of Theta Car  

E-Print Network [OSTI]

Context : The peculiar hot star Theta Car in the open cluster IC2602 is a blue straggler as well as a single-line binary of short period (2.2d). Aims : Its high-energy properties are not well known, though X-rays can provide useful constraints on the energetic processes at work in binaries as well as in peculiar, single objects. Methods : We present the analysis of a 50ks exposure taken with the XMM-Newton observatory. It provides medium as well as high-resolution spectroscopy. Results : Our high-resolution spectroscopy analysis reveals a very soft spectrum with multiple temperature components (1--6MK) and an X-ray flux slightly below the `canonical' value (log[L_X(0.1-10.)/L_{BOL}] ~ -7). The X-ray lines appear surprisingly narrow and unshifted, reminiscent of those of beta Cru and tau Sco. Their relative intensities confirm the anomalous abundances detected in the optical domain (C strongly depleted, N strongly enriched, O slightly depleted). In addition, the X-ray data favor a slight depletion in neon and iron, but they are less conclusive for the magnesium abundance (solar-like?). While no significant changes occur during the XMM-Newton observation, variability in the X-ray domain is detected on the long-term range. The formation radius of the X-ray emission is loosely constrained to <5 R_sol, which allows for a range of models (wind-shock, corona, magnetic confinement,...) though not all of them can be reconciled with the softness of the spectrum and the narrowness of the lines.

Yael Naze; Gregor Rauw

2008-08-25T23:59:59.000Z

146

Array detector for high energy laser based on diffuse transmission sampling  

SciTech Connect (OSTI)

In order to improve the ability and accuracy of measuring the temporal–spatial distribution of the intensity of a large-size, high-energy laser beam, a novel array detecting method based on diffuse transmission sampling is proposed. The measurement principle and the design of the sampling and attenuating unit are presented. High-temperature-resistant diffuse transmission material is used to sample and attenuate a high energy laser beam. Pure copper, whose surface is first sand-blasted and then gold-plated, is applied to scatter the incident high-energy laser beam. The formula for the attenuation ratio was derived in detail. We developed two large-aperture array detectors with spatial resolution of 5 mm, spatial duty ratio of 20%, and useable angle range of ±30° without varying the responsivity, the non-uniformity in the laser profile measurement is below 1%, and the repeatability error in the laser power measurement is approximately 1%. The maximal energy density that the array detector can endure is more than 10 kJ/cm{sup 2}.

Pang, Miao [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China) [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang, 621900 China (China); Key Laboratory of High Energy Laser, CAEP, Mianyang 621900 (China); Rong, Jian [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China)] [School of Physical Electronics, University of Electronic Science and Technology of China, Chengdu 610054 (China); Zhou, Shan; Wu, Juan; Zhang, Wei; Hu, Xiaoyang [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang, 621900 China (China)] [Institute of Applied Electronics, China Academy of Engineering Physics, Mianyang, 621900 China (China); Fan, Guobin [Key Laboratory of High Energy Laser, CAEP, Mianyang 621900 (China)] [Key Laboratory of High Energy Laser, CAEP, Mianyang 621900 (China)

2014-01-15T23:59:59.000Z

147

Safety approaches for high power modular laser operation  

SciTech Connect (OSTI)

Approximately 20 years ago, a program was initiated at the Lawrence Livermore National Laboratory (LLNL) to study the feasibility of using lasers to separate isotopes of uranium and other materials. Of particular interest has been the development of a uranium enrichment method for the production of commercial nuclear power reactor fuel to replace current more expensive methods. The Uranium Atomic Vapor Laser Isotope Separation (U-AVLIS) Program has progressed to the point where a plant-scale facility to demonstrate commercial feasibility has been built and is being tested. The U-AVLIS Program uses copper vapor lasers which pump frequency selective dye lasers to photoionize uranium vapor produced by an electron beam. The selectively ionized isotopes are electrostatically collected. The copper lasers are arranged in oscillator/amplifier chains. The current configuration consists of 12 chains, each with a nominal output of 800 W for a system output in excess of 9 kW. The system requirements are for continuous operation (24 h a day, 7 days a week) and high availability. To meet these requirements, the lasers are designed in a modular form allowing for rapid change-out of the lasers requiring maintenance. Since beginning operation in early 1985, the copper lasers have accumulated over 2 million unit hours at a >90% availability. The dye laser system provides approximately 2.5 kW average power in the visible wavelength range. This large-scale laser system has many safety considerations, including high-power laser beams, high voltage, and large quantities ({approximately}3000 gal) of ethanol dye solutions. The Laboratory`s safety policy requires that safety controls be designed into any process, equipment, or apparatus in the form of engineering controls. Administrative controls further reduce the risk to an acceptable level. Selected examples of engineering and administrative controls currently being used in the U-AVLIS Program are described.

Handren, R.T.

1993-03-01T23:59:59.000Z

148

High resolution A/D conversion based on piecewise conversion at lower resolution  

DOE Patents [OSTI]

Piecewise conversion of an analog input signal is performed utilizing a plurality of relatively lower bit resolution A/D conversions. The results of this piecewise conversion are interpreted to achieve a relatively higher bit resolution A/D conversion without sampling frequency penalty.

Terwilliger, Steve (Albuquerque, NM)

2012-06-05T23:59:59.000Z

149

Compact and mobile high resolution PET brain imager  

DOE Patents [OSTI]

A brain imager includes a compact ring-like static PET imager mounted in a helmet-like structure. When attached to a patient's head, the helmet-like brain imager maintains the relative head-to-imager geometry fixed through the whole imaging procedure. The brain imaging helmet contains radiation sensors and minimal front-end electronics. A flexible mechanical suspension/harness system supports the weight of the helmet thereby allowing for patient to have limited movements of the head during imaging scans. The compact ring-like PET imager enables very high resolution imaging of neurological brain functions, cancer, and effects of trauma using a rather simple mobile scanner with limited space needs for use and storage.

Majewski, Stanislaw (Yorktown, VA); Proffitt, James (Newport News, VA)

2011-02-08T23:59:59.000Z

150

Towards wide-field high-resolution retinal imaging  

E-Print Network [OSTI]

Adaptive optical correction is an efficient technique to obtain high-resolution images of the retinal surface. A main limitation of adaptive optical correction, however, is the small size of the corrected image. For medical purposes it is important to increase the size of the corrected images. This can be done through composite imaging, but a major difficulty is then the introduction of reconstruction artifacts. Another approach is multi-conjugate adaptive optics. MCAO comes in two flavors. The star- oriented approach has been demonstrated on the eye and allows to increase the diameter of the corrected image by a factor of approximately 2-3. Difficulties in the tomographic reconstruction precludes the correction of larger fields. Here we have investigate the possibility to apply a layer-oriented MCAO approach to retinal imaging.

Kellerer, Aglae

2015-01-01T23:59:59.000Z

151

Diamond-machined ZnSe immersion grating for NIR high-resolution spectroscopy  

SciTech Connect (OSTI)

ZnSe immersion gratings (n {approx} 2.45) provide the possibility of high-resolution spectroscopy for the near-infrared (NIR) region. Since ZnSe has a lower internal attenuation than other NIR materials, it is most suitable for immersion grating, particularly in short NIR region (0.8-1.4 {micro}m). We are developing an extremely high-resolution spectrograph with {lambda}/{Delta}{lambda} = 100,000, WINERED, customized for the short NIR region, using ZnSe (or ZnS) immersion grating. However, it had been very difficult to make fine grooves on ZnSe substrate with a small pitch of less than 50 {micro}m because ZnSe is a soft/brittle material. We have overcome this problem and successfully machined sharp grooves with fine pitch on ZnSe substrates by nano precision fly-cutting technique at LLNL. The optical testing of the sample grating with HeNe laser shows an excellent performance: the relative efficiency more than 87.4 % at 0.633 {micro}m for a classical grating configuration. The diffraction efficiency when used as an immersion grating is estimated to be more than 65 % at 1 {micro}m. Following this progress, we are about to start machining a grating on a large ZnSe prism with an entrance aperture of 23mm x 50mm and the blaze angle of 70{sup o}.

Ikeda, Y; Kobayashi, N; Kuzmenko, P J; Little, S L; Yasui, C; Kondo, S; Minami, A; Motohara, K

2008-07-25T23:59:59.000Z

152

A high-resolution imaging x-ray crystal spectrometer for high energy density plasmas  

SciTech Connect (OSTI)

Adapting a concept developed for magnetic confinement fusion experiments, an imaging crystal spectrometer has been designed and tested for HED plasmas. The instrument uses a spherically bent quartz [211] crystal with radius of curvature of 490.8 mm. The instrument was tested at the Titan laser at Lawrence Livermore National Laboratory by irradiating titanium slabs with laser intensities of 10{sup 19}–10{sup 20} W/cm{sup 2}. He-like and Li-like Ti lines were recorded, from which the spectrometer performance was evaluated. This spectrometer provides very high spectral resolving power (E/dE > 7000) while acquiring a one-dimensional image of the source.

Chen, Hui, E-mail: chen33@llnl.gov, E-mail: bitter@pppl.gov; Magee, E.; Nagel, S. R.; Park, J.; Schneider, M. B.; Stone, G.; Williams, G. J.; Beiersdorfer, P. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550-9234 (United States); Bitter, M., E-mail: chen33@llnl.gov, E-mail: bitter@pppl.gov; Hill, K. W. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Kerr, S. [Department of Applied Science, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada)

2014-11-15T23:59:59.000Z

153

Design of high efficiency Mid IR QCL lasers  

E-Print Network [OSTI]

The proposed research is a study of designing high-efficiency Mid-IR quantum cascade lasers (QCL). This thesis explores "injector-less" designs for achieving lower voltage defects and improving wall plug efficiencies through ...

Hsu, Allen Long

2008-01-01T23:59:59.000Z

154

Cryogenic, high-resolution x-ray detector with high count rate capability  

DOE Patents [OSTI]

A cryogenic, high-resolution X-ray detector with high count rate capability has been invented. The new X-ray detector is based on superconducting tunnel junctions (STJs), and operates without thermal stabilization at or below 500 mK. The X-ray detector exhibits good resolution (.about.5-20 eV FWHM) for soft X-rays in the keV region, and is capable of counting at count rates of more than 20,000 counts per second (cps). Simple, FET-based charge amplifiers, current amplifiers, or conventional spectroscopy shaping amplifiers can provide the electronic readout of this X-ray detector.

Frank, Matthias (Oakland, CA); Mears, Carl A. (Windsor, CA); Labov, Simon E. (Berkeley, CA); Hiller, Larry J. (Livermore, CA); Barfknecht, Andrew T. (Menlo Park, CA)

2003-03-04T23:59:59.000Z

155

High-quality electron beam from laser wake-field acceleration in laser produced plasma plumes  

SciTech Connect (OSTI)

Generation of highly collimated ({theta}{sub div}{approx}10 mrad), quasi-monoenergetic electron beam with peak energy 12 MeV and charge {approx}50 pC has been experimentally demonstrated from self-guided laser wake-field acceleration (LWFA) in a plasma plume produced by laser ablation of solid nylon (C{sub 12}H{sub 22}N{sub 2}O{sub 2}){sub n} target. A 7 TW, 45 fs Ti:sapphire laser system was used for LWFA, and the plasma plume forming pulse was derived from the Nd:YAG pump laser of the same system. The results show that a reproducible, high quality electron beam could be produced from this scheme which is simple, low cost and has the capability for high repetition rate operation.

Sanyasi Rao, Bobbili; Moorti, Anand; Rathore, Ranjana; Ali Chakera, Juzer; Anant Naik, Prasad; Dass Gupta, Parshotam [Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)] [Laser Plasma Division, Raja Ramanna Centre for Advanced Technology, Indore 452013 (India)

2013-06-10T23:59:59.000Z

156

Laser-Energy Transfer and Enhancement of Plasma Waves and Electron Beams by Interfering High-Intensity Laser Pulses  

E-Print Network [OSTI]

Laser-Energy Transfer and Enhancement of Plasma Waves and Electron Beams by Interfering High-Intensity) The effects of interference due to crossed laser beams were studied experimentally in the high- intensity regime. Two ultrashort (400 fs), high-intensity (4 1017 and 1:6 1018 W=cm2) and 1 m wavelength laser

Umstadter, Donald

157

High Power Lasers... Another approach to  

E-Print Network [OSTI]

as an integrated system Simultaneously addressing the science and engineering Direct Drive Pellet Designs Computer and technologies together, using the end goal of a practical power source as a guide Lasers DPPSL (LLNL) KrF (NRL) Target Fabrication Target Injection Chamber/Materials Final Optics Target Design (+NRL & LLE ) #12

158

Ultra-high Resolution Optics for EUV and Soft X-ray Inelastic Scattering  

E-Print Network [OSTI]

16. Yu. Shvyd’ko, X-Ray Optics, Berlin: Springer-Verlag,Ultra-high Resolution Optics for EUV and Soft X-rayspectral resolution soft x-ray optics. Conventionally in the

Voronov, Dmitry L.

2010-01-01T23:59:59.000Z

159

High resolution neutron imaging of water in PEM fuel cells  

SciTech Connect (OSTI)

Optimal water management in Polymer Electrolyte Membrane (PEM) fuel cells is critical to improving the performance and durability of fuel cell systems especially during transient, start-up and shut-down operations. For example, while a high water content is desirable for improved membrane and catalyst ionomer conductivity, high water content can also block gas access to the triple-phase boundary resulting in lowered performance due to catalyst and gas diffusion layer (GDL) flooding. Visualizing liquid water by neutron imaging has been used over the past decade to study the water distribution inside operating fuel cells. In this paper, the results from our imaging at NIST using their recently installed higher resolution ({approx} 25 mm) Microchannel Plate (MCP) detector with a pixel pitch of 14.7 mm are presented. This detector is capable of quantitatively imaging the water inside the MEA (Membrane Electrode Assembly)/GDL (Gas Diffusion Layer) of working fuel cells and can provide the water profiles within these various components in addition to the channel water. Specially designed fuel cells (active area = 2.25 cm{sup 2}) have been used in order to take advantage of the full detector resolution. The cell design is illustrated in a figure where one of the current collector/end plates is shown. The serpentine pattern was machined into a block of aluminum and plated with nickel and then gold to form the flow field. The measurements were performed using beam no. 1 and aperture no. 2 with a fluence rate of 1.9 x 10{sup 6} neutrons cm{sup -2} sec{sup -1}. The cells were assembled with Gore{sup TM} Primea{sup R} MEAs and SGL Sigracet {sup R} 24 series GDLs (PRIMEA, GORE-SELECT and GORE are trademarks of W. L. Gore & Associates, Inc). All the cells were tested at 80 {sup o}C with 1.2 stoichiometry H{sub 2} and 2.0 stoichiometry air flows.

Mukundan, Rangachary [Los Alamos National Laboratory; Borup, Rodney L [Los Alamos National Laboratory; Davey, John R [Los Alamos National Laboratory; Spendelow, Jacob S [Los Alamos National Laboratory

2008-01-01T23:59:59.000Z

160

High-power laser source evaluation  

SciTech Connect (OSTI)

This document reports progress in these areas: EXPERIMENTAL RESULTS FROM NOVA: TAMPED XENON UNDERDENSE X-RAY EMITTERS; MODELING MULTI-KEV RADIATION PRODUCTION OF XENON-FILLED BERYLLIUM CANS; MAPPING A CALCULATION FROM LASNEX TO CALE; HOT X RAYS FROM SEEDED NIF CAPSULES; HOHLRAUM DEBRIS MEASUREMENTS AT NOVA; FOAM AND STRUCTURAL RESPONSE CALCULATIONS FOR NIF NEUTRON EXPOSURE SAMPLE CASE ASSEMBLY DESIGN; NON-IGNITION X-RAY SOURCE FLUENCE-AREA PRODUCTS FOR NUCLEAR EFFECTS TESTING ON NIF. Also appended are reprints of two papers. The first is on the subject of ``X-Ray Production in Laser-Heated Xe Gas Targets.`` The second is on ``Efficient Production and Applications of 2- to 10-keV X Rays by Laser-Heated Underdense Radiators.``

Back, C.A.; Decker, C.D.; Dipeso, G.J.; Gerassimenko, M.; Managan, R.A.; Serduke, F.J.D.; Simonson, G.F.; Suter, L.J.

1997-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Aluminium plasma production at high laser intensity  

SciTech Connect (OSTI)

Thick and thin films of Al targets were irradiated in vacuum with iodine laser at 1315?nm wavelength, 300 ps pulse duration at a maximum intensity of about 10{sup 16}?W/cm{sup 2} by varying the pulse energy and focal position. The laser-generated plasma was monitored in forward and backward directions by using ion collectors, SiC detectors, Thomson parabola spectrometer, and X-ray streak camera. Ion emission shows maximum proton energy of about 4?MeV in self-focusing conditions and a maximum Al ion energy of about 50?MeV. An evaluation of the electric field driving ions in conditions of target normal sheath acceleration is given.

Torrisi, L.; Cutroneo, M. [Dip.to di Fisica e S.d.T. Università di Messina, V.S. d'Alcontres 31, 98166 S. Agata (Italy)

2014-02-28T23:59:59.000Z

162

Small UAV-Acquired, High-resolution, Georeferenced Still Imagery  

SciTech Connect (OSTI)

Currently, small Unmanned Aerial Vehicles (UAVs) are primarily used for capturing and down-linking real-time video. To date, their role as a low-cost airborne platform for capturing high-resolution, georeferenced still imagery has not been fully utilized. On-going work within the Unmanned Vehicle Systems Program at the Idaho National Laboratory (INL) is attempting to exploit this small UAV-acquired, still imagery potential. Initially, a UAV-based still imagery work flow model was developed that includes initial UAV mission planning, sensor selection, UAV/sensor integration, and imagery collection, processing, and analysis. Components to support each stage of the work flow are also being developed. Critical to use of acquired still imagery is the ability to detect changes between images of the same area over time. To enhance the analysts’ change detection ability, a UAV-specific, GIS-based change detection system called SADI or System for Analyzing Differences in Imagery is under development. This paper will discuss the associated challenges and approaches to collecting still imagery with small UAVs. Additionally, specific components of the developed work flow system will be described and graphically illustrated using varied examples of small UAV-acquired still imagery.

Ryan Hruska

2005-09-01T23:59:59.000Z

163

High energy KrCl electric discharge laser  

DOE Patents [OSTI]

A high energy KrCl laser for producing coherent radiation at 222 nm. Output energies on the order of 100 mJ per pulse are produced utilizing a discharge excitation source to minimize formation of molecular ions, thereby minimizing absorption of laser radiation by the active medium. Additionally, HCl is used as a halogen donor which undergoes a harpooning reaction with metastable Kr.sub.M * to form KrCl.

Sze, Robert C. (Santa Fe, NM); Scott, Peter B. (Los Alamos, NM)

1981-01-01T23:59:59.000Z

164

Transverse spreading of electrons in high-intensity laser fields  

E-Print Network [OSTI]

We show that for collisions of electrons with a high-intensity laser, discrete photon emissions introduce a transverse beam spread which is distinct from that due to classical (or beam shape) effects. Via numerical simulations, we show that this quantum induced transverse momentum gain of the electron is manifest in collisions with a realistic laser pulse of intensity within reach of current technology, and we propose it as a measurable signature of strong-field quantum electrodynamics.

D. G. Green; C. N. Harvey

2014-03-18T23:59:59.000Z

165

Measurement method for roll angular displacement with a high resolution by using diffraction gratings and a heterodyne interferometer  

SciTech Connect (OSTI)

The roll angle measurement is difficult to be achieved directly using a typical commercial interferometer due to its low sensitivity in axial direction, where the axial direction is orthogonal to the plane of the roll angular displacement. A roll angle measurement method combined diffraction gratings with a laser heterodyne interferometer is discussed in this paper. The diffraction grating placed in the plane of a roll angular displacement and the interferometer arranged in the plane's orthogonal direction, constitute the measurement pattern for the roll angle with high resolution. The roll angular displacement, considered as the linear, can be tested precisely when the corresponding angle is very small. Using the proposed method, the angle roll measurement obtains the high resolution of 0.002{sup ?}. Experiment has proved its feasibility and practicability.

Tang, Shanzhi, E-mail: shanzhit@gmail.com [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China) [Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049 (China); School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049 (China); Wang, Zhao [School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049 (China)] [School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an 710049 (China); Gao, Jianmin; Guo, Junjie [State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054 (China)] [State Key Laboratory for Manufacturing Systems Engineering, Xi'an Jiaotong University, Xi'an 710054 (China)

2014-04-15T23:59:59.000Z

166

The performance of Lagrangian perturbation schemes at high resolution  

E-Print Network [OSTI]

We present high--spatial resolution studies of the density field as predicted by Lagrangian perturbation approximations up to the third order. The first--order approximation is equivalent to the ``Zel'dovich approximation'' for the type of initial data analyzed. The study is performed for two simple models which allow studying of typical features of the clustering process in the early non--linear regime. We calculate the initial perturbation potentials as solutions of Poisson equations algebraically, and automate this calculation for a given initial random density field. The presented models may also be useful for other questions addressed to Lagrangian perturbation solutions and for the comparison of different approximation schemes. In an accompanying paper we investigate a detailed comparison with various N--body integrators using these models (Karakatsanis \\& Buchert 1995). Results of the present paper include the following: 1. The collapse is accelerated significantly by the higher--order corrections confirming previous results by Moutarde \\etal (1991); 2. the spatial structure of the density patterns predicted by the ``Zel'dovich approximation'' differs much from those predicted by the second-- and third--order Lagrangian approximations; 3. Second--order effects amount to internal substructures such as ``second generation'' --pancakes, --filaments and --clusters, as are also observed in N--body simulations; 4. The third--order effect gives rise to substructuring of the secondary mass--shells. The hierarchy of shell--crossing singularities that form features small high--density clumps at the intersections of caustics which we interprete as gravitational fragmentation.

Thomas Buchert; Georgios Karakatsanis; Robert Klaffl; Peter Schiller

1995-10-25T23:59:59.000Z

167

Chandra High Resolution X-ray Spectroscopy of AM Her  

E-Print Network [OSTI]

We present the results of high resolution spectroscopy of the prototype polar AM Herculis observed with Chandra High Energy Transmission Grating. The X-ray spectrum contains hydrogen-like and helium-like lines of Fe, S, Si, Mg, Ne and O with several Fe L-shell emission lines. The forbidden lines in the spectrum are generally weak whereas the hydrogen-like lines are stronger suggesting that emission from a multi-temperature, collisionally ionized plasma dominates. The helium-like line flux ratios yield a plasma temperature of 2 MK and a plasma density 1 - 9 x10^12 cm^-3, whereas the line flux ratio of Fe XXVI to Fe XXV gives an ionization temperature of 12.4 +1.1 -1.4 keV. We present the differential emission measure distribution of AM Her whose shape is consistent with the volume emission measure obtained by multi-temperature APEC model. The multi-temperature plasma model fit to the average X-ray spectrum indicates the mass of the white dwarf to be ~1.15 M_sun. From phase resolved spectroscopy, we find the line centers of Mg XII, S XVI, resonance line of Fe XXV, and Fe XXVI emission modulated by a few hundred to 1000 km/s from the theoretically expected values indicating bulk motion of ionized matter in the accretion column of AM Her. The observed velocities of Fe XXVI ions are close to the expected shock velocity for a 0.6 M_sun white dwarf. The observed velocity modulation is consistent with that expected from a single pole accreting binary system.

V. Girish; V. R. Rana; K. P. Singh

2007-02-14T23:59:59.000Z

168

High-Energy Laser Diagnostics (HELD) for the Measurement of Diesel...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Energy Laser Diagnostics (HELD) for the Measurement of Diesel Particulate Matter High-Energy Laser Diagnostics (HELD) for the Measurement of Diesel Particulate Matter 2004 Diesel...

169

High resolution resonance ionization imaging detector and method  

DOE Patents [OSTI]

A resonance ionization imaging device (RIID) and method for imaging objects using the RIID are provided, the RIID system including a RIID cell containing an ionizable vapor including monoisotopic atoms or molecules, the cell being positioned to intercept scattered radiation of a resonance wavelength .lambda..sub.1 from the object which is to be detected or imaged, a laser source disposed to illuminate the RIID cell with laser radiation having a wavelength .lambda..sub.2 or wavelengths .lambda..sub.2, .lambda..sub.3 selected to ionize atoms in the cell that are in an excited state by virtue of having absorbed the scattered resonance laser radiation, and a luminescent screen at the back surface of the RIID cell which presents an image of the number and position of charged particles present in the RIID cell as a result of the ionization of the excited state atoms. The method of the invention further includes the step of initially illuminating the object to be detected or imaged with a laser having a wavelength selected such that the object will scatter laser radiation having the resonance wavelength .lambda..sub.1.

Winefordner, James D. (Gainesville, FL); Matveev, Oleg I. (Gainesville, FL); Smith, Benjamin W. (Gainesville, FL)

1999-01-01T23:59:59.000Z

170

Laser assisted high entropy alloy coating on aluminum: Microstructural evolution  

SciTech Connect (OSTI)

High entropy alloy (Al-Fe-Co-Cr-Ni) coatings were synthesized using laser surface engineering on aluminum substrate. Electron diffraction analysis confirmed the formation of solid solution of body centered cubic high entropy alloy phase along with phases with long range periodic structures within the coating. Evolution of such type of microstructure was a result of kinetics associated with laser process, which generates higher temperatures and rapid cooling resulting in retention of high entropy alloy phase followed by reheating and/or annealing in subsequent passes of the laser track giving rise to partial decomposition. The partial decomposition resulted in formation of precipitates having layered morphology with a mixture of high entropy alloy rich phases, compounds, and long range ordered phases.

Katakam, Shravana; Joshi, Sameehan S.; Mridha, Sanghita; Mukherjee, Sundeep; Dahotre, Narendra B., E-mail: Narendra.Dahotre@unt.edu [Department of Materials Science and Engineering, University of North Texas, 1150 Union Circle, 305310 Denton, Texas 76203-5017 (United States)

2014-09-14T23:59:59.000Z

171

Dichroic beamsplitter for high energy laser diagnostics  

DOE Patents [OSTI]

Wavefront control techniques are provided for the alignment and performance optimization of optical devices. A Shack-Hartmann wavefront sensor can be used to measure the wavefront distortion and a control system generates feedback error signal to optics inside the device to correct the wavefront. The system can be calibrated with a low-average-power probe laser. An optical element is provided to couple the optical device to a diagnostic/control package in a way that optimizes both the output power of the optical device and the coupling of the probe light into the diagnostics.

LaFortune, Kai N (Livermore, CA); Hurd, Randall (Tracy, CA); Fochs, Scott N (Livermore, CA); Rotter, Mark D (San Ramon, CA); Hackel, Lloyd (Livermore, CA)

2011-08-30T23:59:59.000Z

172

Magnetic nanowire based high resolution magnetic force microscope probes  

E-Print Network [OSTI]

-resolution magnetic force microscope probes using preformed magnetic nanowires. Nickel and cobalt nanowires produced by electrodeposition were directly assembled onto the tip of a commercial atomic force microscope cantilever

Qin, Lu-Chang

173

Method for generating high-energy and high repetition rate laser pulses from CW amplifiers  

DOE Patents [OSTI]

A method for obtaining high-energy, high repetition rate laser pulses simultaneously using continuous wave (CW) amplifiers is described. The method provides for generating micro-joule level energy in pico-second laser pulses at Mega-hertz repetition rates.

Zhang, Shukui

2013-06-18T23:59:59.000Z

174

INNER SHELL EXCITATION OF ATOMS AND MOLECULES BY ELECTRON IMPACT WITH HIGH ENERGY RESOLUTION  

E-Print Network [OSTI]

INNER SHELL EXCITATION OF ATOMS AND MOLECULES BY ELECTRON IMPACT WITH HIGH ENERGY RESOLUTION F. H resolution energy loss spectra for inner shell excited states, (2) the observa- tion of inner shell excited are the subject of the present review. The inner shell states that can usefully be studied with energy resolutions

Paris-Sud XI, Université de

175

High-Intensity Coherent Vacuum Ultraviolet Source Using Unfocussed Commercial Dye Lasers  

E-Print Network [OSTI]

1 High-Intensity Coherent Vacuum Ultraviolet Source Using Unfocussed Commercial Dye Lasers Daniel R Intruments Using two or three commercial pulsed nanosecond dye lasers pumped by a single 30 Hz Nd:YAG laser

Davis, H. Floyd

176

Bright High Average Power Table-top Soft X-Ray Lasers  

SciTech Connect (OSTI)

We have demonstrated the generation of bright soft x-ray laser pulses with record-high average power from compact plasma amplifiers excited by ultrafast solid state lasers. These lasers have numerous applications in nanoscience and nanotechnology.

Rocca, Jorge [Colorado State University, Fort Collins; Reagan, Brendon [Colorado State University, Fort Collins; Wernsing, Keith [Colorado State University, Fort Collins; Luther, Brad [Colorado State University, Fort Collins; Curtis, Alden [Colorado State University, Fort Collins; Nichols,, Anthony [Colorado State University, Fort Collins; Wang, Yong [Colorado State University, Fort Collins; Alessi, David [Colorado State University, Fort Collins; Martz, Dale [Colorado State University, Fort Collins; Yin, Liang [Colorado State University, Fort Collins; Wang, Shoujun [Colorado State University, Fort Collins; Berrill, Mark A [ORNL; Furch, Federico [Colorado State University, Fort Collins; Woolston, Mark [Colorado State University, Fort Collins; Patel, Dinesh [Colorado State University, Fort Collins; Marconi, Mario [Colorado State University, Fort Collins; Menoni, Carmen [Colorado State University, Fort Collins

2012-01-01T23:59:59.000Z

177

High brightness diode-pumped organic solid-state laser  

E-Print Network [OSTI]

High-power, diffraction-limited organic solid-state laser operation has been achieved in a vertical external cavity surface-emitting organic laser (VECSOL), pumped by a low-cost compact blue laser diode. The diode-pumped VECSOLs were demonstrated with various dyes in a polymer matrix, leading to laser emissions from 540 nm to 660 nm. Optimization of both the pump pulse duration and output coupling leads to a pump slope efficiency of 11% for a DCM based VECSOLs. We report output pulse energy up to 280 nJ with 100 ns long pump pulses, leading to a peak power of 3.5 W in a circularly symmetric, diffraction-limited beam.

Zhao, Zhuang; Nafa, Malik; Chénais, Sébastien; Forget, Sébastien

2015-01-01T23:59:59.000Z

178

Recording high-resolution wavelength-multiplexed data pages in a Lippmann data storage system  

E-Print Network [OSTI]

Recording high-resolution wavelength-multiplexed data pages in a Lippmann data storage system storage densities. 2. Lippmann data storage systems Applying the Lippmann interference color photographic

Paris-Sud XI, Université de

179

applying high-resolution detectors: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

since Spring 1999. Stereo 3 Using High-Resolution Detector and Signal Data to Support Energy Storage, Conversion and Utilization Websites Summary: data collection and storage...

180

E-Print Network 3.0 - adaptive high-resolution simulation Sample...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

URBAN TO REGIONAL SCALE AIR QUALITY PROBLEMS Summary: are limited. We are using hourly data from a very high resolution fixed grid MMM simulation and interpolating... the adapted...

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

RAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION  

E-Print Network [OSTI]

function (GMF) which relates wind to backscatter (0 ) is not well understood for extremely high wind speedsRAIN AND WIND ESTIMATION FROM SEAWINDS IN HURRICANES AT ULTRA HIGH RESOLUTION Brent A. Williams method for estimating wind and rain in hurricanes from SeaWinds at ultra-high resolution is developed. We

Long, David G.

182

High removal rate laser-based coating removal system  

DOE Patents [OSTI]

A compact laser system that removes surface coatings (such as paint, dirt, etc.) at a removal rate as high as 1000 ft.sup.2 /hr or more without damaging the surface. A high repetition rate laser with multiple amplification passes propagating through at least one optical amplifier is used, along with a delivery system consisting of a telescoping and articulating tube which also contains an evacuation system for simultaneously sweeping up the debris produced in the process. The amplified beam can be converted to an output beam by passively switching the polarization of at least one amplified beam. The system also has a personal safety system which protects against accidental exposures.

Matthews, Dennis L. (Moss Beach, CA); Celliers, Peter M. (Berkeley, CA); Hackel, Lloyd (Livermore, CA); Da Silva, Luiz B. (Danville, CA); Dane, C. Brent (Livermore, CA); Mrowka, Stanley (Richmond, CA)

1999-11-16T23:59:59.000Z

183

High resolution non-contact thermal characterization of semiconductor devices  

E-Print Network [OSTI]

imaging can have spatial resolution better than the diffraction limit of an infrared camera and can work infrared microscopes. Also, since the thermoreflectance technique does not rely upon the emitted black body measured the heating on a 35x35 micron MOS transistor, and Mansanares5 who measured temperature

184

Probe for high resolution NMR with sample reorientation  

DOE Patents [OSTI]

An improved NMR probe and method are described which substantially improve the resolution of NMR measurements made on powdered or amorphous or otherwise orientationally disordered samples. The apparatus mechanically varies the orientation of the sample such that the time average of two or more sets of spherical harmonic functions are zero.

Pines, Alexander (Berkeley, CA); Samoson, Ago (Tallinn, SU)

1990-01-01T23:59:59.000Z

185

Probe for high resolution NMR with sample reorientation  

DOE Patents [OSTI]

An improved NMR probe and method are described which substantially improve the resolution of NMR measurements made on powdered or amorphous or otherwise orientationally disordered samples. The apparatus mechanically varies the orientation of the sample such that the time average of two or more sets of spherical harmonic functions are zero. 8 figs.

Pines, A.; Samoson, A.

1990-02-06T23:59:59.000Z

186

High Rate Laser Pitting Technique for Solar Cell Texturing  

SciTech Connect (OSTI)

High rate laser pitting technique for solar cell texturing Efficiency of crystalline silicon solar cells can be improved by creating a texture on the surface to increase optical absorption. Different techniques have been developed for texturing, with the current state-of-the-art (SOA) being wet chemical etching. The process has poor optical performance, produces surfaces that are difficult to passivate or contact and is relatively expensive due to the use of hazardous chemicals. This project shall develop an alternative process for texturing mc-Si using laser micromachining. It will have the following features compared to the current SOA texturing process: -Superior optical surfaces for reduced front-surface reflection and enhanced optical absorption in thin mc-Si substrates -Improved surface passivation -More easily integrated into advanced back-contact cell concepts -Reduced use of hazardous chemicals and waste treatment -Similar or lower cost The process is based on laser pitting. The objective is to develop and demonstrate a high rate laser pitting process which will exceed the rate of former laser texturing processes by a factor of ten. The laser and scanning technologies will be demonstrated on a laboratory scale, but will use inherently technologies that can easily be scaled to production rates. The drastic increase in process velocity is required for the process to be implemented as an in-line process in PV manufacturing. The project includes laser process development, development of advanced optical systems for beam manipulation and cell reflectivity and efficiency testing. An improvement of over 0.5% absolute in efficiency is anticipated after laser-based texturing. The surface textures will be characterized optically, and solar cells will be fabricated with the new laser texturing to ensure that the new process is compatible with high-efficiency cell processing. The result will be demonstration of a prototype process that is suitable for scale-up to a production tool and process. The developed technique will have an reducing impact on product pricing. As efficiency has a substantial impact on the economics of solar cell production due to the high material cost content; in essence, improved efficiency through cost-effective texturing reduces the material cost component since the product is priced in terms of $/W. The project is a collaboration between Fraunhofer USA, Inc. and a c-Si PV manufacturer.

Hans J. Herfurth; Henrikki Pantsar

2013-01-10T23:59:59.000Z

187

The design and construction of a high-resolution velocity-map imaging apparatus for photoelectron spectroscopy studies of size-selected clusters  

SciTech Connect (OSTI)

A new velocity-map imaging apparatus equipped with a laser-vaporization supersonic cluster source and a time-of-flight mass spectrometer is described for high-resolution photoelectron spectroscopy studies of size-selected cluster anions. Vibrationally cold anion clusters are produced using a laser-vaporization supersonic cluster source, size-selected by a time-of-flight mass spectrometer, and then focused co-linearly into the interaction zone of the high-resolution velocity-map imaging (VMI) system. The multilens VMI system is optimized via systematic simulations and can reach a resolution of 1.2 cm{sup ?1} (FWHM) for near threshold electrons while maintaining photoelectron kinetic energy resolutions (?KE/KE) of ?0.53% for higher energy electrons. The new VMI lens has superior focusing power over a large energy range, yielding highly circular images with distortions no larger than 1.0025 between the long and short radii. The detailed design, simulation, construction, testing, and performance of the high-resolution VMI apparatus are presented.

León, Iker; Yang, Zheng; Liu, Hong-Tao; Wang, Lai-Sheng, E-mail: Lai-Sheng-Wang@brown.edu [Department of Chemistry, Brown University, Providence, Rhode Island 02912 (United States)

2014-08-15T23:59:59.000Z

188

High-current-density, high brightness cathodes for free electron laser applications  

SciTech Connect (OSTI)

This report discusses the following topics: brightness and emittance of electron beams and cathodes; general requirements for cathodes in high brightness electron guns; candidate cathode types; plasma and field emission cathodes; true field emission cathodes; oxide cathodes; lanthanum hexaborides cathodes; laser driven thermionic cathodes; laser driven photocathodes; impregnated porous tungsten dispenser cathodes; and choice of best performing cathode types.

Green, M.C. (Varian Associates, Palo Alto, CA (USA). Palo Alto Microwave Tube Div.)

1987-06-01T23:59:59.000Z

189

High density, optically corrected, micro-channel cooled, v-groove monolithic laser diode array  

DOE Patents [OSTI]

An optically corrected, micro-channel cooled, high density laser diode array achieves stacking pitches to 33 bars/cm by mounting laser diodes into V-shaped grooves. This design will deliver>4kW/cm2 of directional pulsed laser power. This optically corrected, micro-channel cooled, high density laser is usable in all solid state laser systems which require efficient, directional, narrow bandwidth, high optical power density pump sources.

Freitas, Barry L. (Livermore, CA)

1998-01-01T23:59:59.000Z

190

High energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from  

E-Print Network [OSTI]

, Albuquerque, New Mexico. ~Received 21 February 2005; Accepted 20 April 2005! Abstract High energy heavy ions to the fast ion emission process. The interest in laser plasmas and interaction phenomena of heavy ion beams!. Thus there is a tradition to investigate accelerator related issues like beam transport phenomena

191

Design of a subnanometer resolution beam position monitor for dielectric laser accelerators  

E-Print Network [OSTI]

of the first laser-powered particle accel- erators "on a chip" [1,2]. These devices are specifically designed present a new concept for a beam position monitor with the unique ability to map particle beam position, this device is ideal for future x-ray sources and laser-driven particle accelerators "on a chip." © 2012

Byer, Robert L.

192

A NEW HIGH ENERGY RESOLUTION NEUTRON TRANSMISSION DETECTOR SYSTEM AT THE GAERTTNER LINAC LABORATORY  

E-Print Network [OSTI]

Laboratory P.O. Box 1072, Schenectady, New York 12301-1072 A new high energy resolution modular neutronA NEW HIGH ENERGY RESOLUTION NEUTRON TRANSMISSION DETECTOR SYSTEM AT THE GAERTTNER LINAC LABORATORY capabilities at the Laboratory in and above the resolved resonance energy region from 1 keV to 600 ke

Danon, Yaron

193

Cornelis Zwaan, open principle, and the future of high-resolution solar telescopes  

E-Print Network [OSTI]

Cornelis Zwaan, open principle, and the future of high-resolution solar telescopes Robert H erected up till 30 m height with sensors at several heights for the measurement of temperature; (iii) the design consequences for the new generation of high-resolution solar telescopes. Keywords

Rutten, Rob

194

High-resolution friction force microscopy under electrochemical control Aleksander Labuda,1  

E-Print Network [OSTI]

High-resolution friction force microscopy under electrochemical control Aleksander Labuda,1 William and development of a friction force microscope for high-resolution studies in electrochemical environments in liquids. The noise of the system is analyzed based on a methodology for the quantification of all

Grütter, Peter

195

Range imaging: a new method for high-resolution topographic measurements in small-and medium-  

E-Print Network [OSTI]

Range imaging: a new method for high-resolution topographic measurements in small- and medium is a useful complement or alternative to existing methods for high-resolution measurements in small- to medium has led to a dramatic increase in terrain information and opened up new opportunities for hydro- logic

Kirchner, James W.

196

High-resolution fracture aperture mapping using optical profilometry Pasha Ameli,1  

E-Print Network [OSTI]

High-resolution fracture aperture mapping using optical profilometry Pasha Ameli,1 Jean E. Elkhoury] Fractures play an important role in the Earth's crust, often controlling both mechanical and transport of fracture surfaces and the contacts and void spaces between fracture surfaces at high spatial resolution (10

Elkhoury, Jean

197

A high-resolution mapped grid algorithm for compressible multiphase flow problems  

E-Print Network [OSTI]

A high-resolution mapped grid algorithm for compressible multiphase flow problems K.-M. Shyue mapped grid approach for the efficient numerical simula- tion of compressible multiphase flow in general problems, J. Comput. Phys. 142 (1998) 208-242). A standard high-resolution mapped grid method in wave

Shyue, Keh-Ming

198

Ultra High-Resolution Global Climate Simulation Project PRINCIPAL INVESTIGATOR: James J. Hack  

E-Print Network [OSTI]

changes in the frequency and intensity of extreme events. This project is developing the scientific a terrestrial carbon modeling capabil- ity. #12;Ultra High-Resolution Global Climate Simulation Project elersUltra High-Resolution Global Climate Simulation Project PRINCIPAL INVESTIGATOR: James J. Hack

199

High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations  

E-Print Network [OSTI]

High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations Ammar H. Hakim Information and Learning, 300 North Zeeb Road, Ann Arbor, MI 48106-1346, 1-800-521-0600, to whom the author Abstract High Resolution Wave Propagation Schemes for Two-Fluid Plasma Simulations Ammar H. Hakim Chair

Shumlak, Uri

200

HIGH-RESOLUTION LAND/ICE IMAGING USING SEASAT SCATTEROMETER MEASUREMENTS  

E-Print Network [OSTI]

scatterometers which would permit the method to produce 1-2 km resolution over land and ice. The highHIGH-RESOLUTION LAND/ICE IMAGING USING SEASAT SCATTEROMETER MEASUREMENTS D. G. Long*, P. T. Whiting by the scatterometer,is expected to significantly enhance the utility of sca.tteroineter data in various land, ice

Long, David G.

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Automated analysis for microcalcifications in high resolution digital mammograms  

DOE Patents [OSTI]

A method is disclosed for automatically locating microcalcifications indicating breast cancer. The invention assists mammographers in finding very subtle microcalcifications and in recognizing the pattern formed by all the microcalcifications. It also draws attention to microcalcifications that might be overlooked because a more prominent feature draws attention away from an important object. A new filter has been designed to weed out false positives in one of the steps of the method. Previously, iterative selection threshold was used to separate microcalcifications from the spurious signals resulting from texture or other background. A Selective Erosion or Enhancement (SEE) Filter has been invented to improve this step. Since the algorithm detects areas containing potential calcifications on the mammogram, it can be used to determine which areas need be stored at the highest resolution available, while, in addition, the full mammogram can be reduced to an appropriate resolution for the remaining cancer signs. 8 figs.

Mascio, L.N.

1996-12-17T23:59:59.000Z

202

Automated analysis for microcalcifications in high resolution digital mammograms  

DOE Patents [OSTI]

A method for automatically locating microcalcifications indicating breast cancer. The invention assists mammographers in finding very subtle microcalcifications and in recognizing the pattern formed by all the microcalcifications. It also draws attention to microcalcifications that might be overlooked because a more prominent feature draws attention away from an important object. A new filter has been designed to weed out false positives in one of the steps of the method. Previously, iterative selection threshold was used to separate microcalcifications from the spurious signals resulting from texture or other background. A Selective Erosion or Enhancement (SEE) Filter has been invented to improve this step. Since the algorithm detects areas containing potential calcifications on the mammogram, it can be used to determine which areas need be stored at the highest resolution available, while, in addition, the full mammogram can be reduced to an appropriate resolution for the remaining cancer signs.

Mascio, Laura N. (Dublin, CA)

1996-01-01T23:59:59.000Z

203

alveolitis high-resolution computed: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Geiger, Cathleen 45 High-resolution x-ray telescopes CERN Preprints Summary: High-energy astrophysics is a relatively young scientific field, made possible by space-borne...

204

Time-series analysis of high-resolution ebullition fluxes from a stratified, freshwater lake  

E-Print Network [OSTI]

[1] Freshwater lakes can emit significant quantities of methane to the atmosphere by bubbling. The high spatial and temporal heterogeneity of ebullition, combined with a lack of high-resolution field measurements, has made ...

Varadharajan, Charuleka

205

Laser damage of dichroic coatings in a high average power laser vacuum resonator  

SciTech Connect (OSTI)

In our application, dichroics in a high average power, near-infrared, laser system have short operating lifetimes. These dichroics were used as the resonator fold mirrors and permitted the transmission of the pumping argon (Ar) ion laser light. Representative samples of two different dichroic optics were taken off-line and the transmission performance monitored in various scenarios. Irradiating these optics under resonator vacuum conditions, ({le}1 mT, 11.7 kW/cm{sup 2}, Ar laser running all wavelengths) resulted in a degradation of transmission with time. Irradiating these optics in a rarefied oxygen atmosphere (1 to 10 T of oxygen, 11.7 kW/cm{sup 2}, Ar laser running all wavelengths) the transmission remained steady over a period of days. The transmission loss observed in the optic tested in vacuum was somewhat reversible if the optic was subsequently irradiated in a rarefied oxygen atmosphere. This reversibility was only possible if the transmission degradation was not too severe. Further tests demonstrated that an atmosphere of 10 T of air also prevented the transmission degradation. In addition, tests were performed to demonstrate that the optic damage was not caused by the ultra-violet component in the Ar ion laser. Mechanisms that may account for this behavior are proposed.

Arnold, P A; Berzins, L V; Chow, R; Erbert, G V

1999-07-28T23:59:59.000Z

206

Diffraction Gratings for High-Intensity Laser Applications  

SciTech Connect (OSTI)

The scattering of light into wavelength-dependent discrete directions (orders) by a device exhibiting a periodic modulation of a physical attribute on a spatial scale similar to the wavelength of light has been the subject of study for over 200 years. Such a device is called a diffraction grating. Practical applications of diffraction gratings, mainly for spectroscopy, have been around for over 100 years. The importance of diffraction gratings in spectroscopy for the measurement of myriad properties of matter can hardly be overestimated. Since the advent of coherent light sources (lasers) in the 1960's, applications of diffraction gratings in spectroscopy have further exploded. Lasers have opened a vast application space for gratings, and apace, gratings have enabled entirely new classes of laser systems. Excellent reviews of the history, fundamental properties, applications and manufacturing techniques of diffraction gratings up to the time of their publication can be found in the books by Hutley (1) and more recently Loewen and Popov (2). The limited scope of this chapter can hardly do justice to such a comprehensive subject, so the focus here will be narrowly limited to characteristics required for gratings suitable for high-power laser applications, and methods to fabricate them. A particular area of emphasis will be on maximally-efficient large-aperture gratings for short-pulse laser generation.

Britten, J

2008-01-23T23:59:59.000Z

207

Method and system for modulation of gain suppression in high average power laser systems  

DOE Patents [OSTI]

A high average power laser system with modulated gain suppression includes an input aperture associated with a first laser beam extraction path and an output aperture associated with the first laser beam extraction path. The system also includes a pinhole creation laser having an optical output directed along a pinhole creation path and an absorbing material positioned along both the first laser beam extraction path and the pinhole creation path. The system further includes a mechanism operable to translate the absorbing material in a direction crossing the first laser beam extraction laser path and a controller operable to modulate the second laser beam.

Bayramian, Andrew James (Manteca, CA)

2012-07-31T23:59:59.000Z

208

Toroidal magnetic detector for high resolution measurement of muon momenta  

DOE Patents [OSTI]

A muon detector system including central and end air-core superconducting toroids and muon detectors enclosing a central calorimeter/detector. Muon detectors are positioned outside of toroids and all muon trajectory measurements are made in a nonmagnetic environment. Internal support for each magnet structure is provided by sheets, located at frequent and regularly spaced azimuthal planes, which interconnect the structural walls of the toroidal magnets. In a preferred embodiment, the shape of the toroidal magnet volume is adjusted to provide constant resolution over a wide range of rapidity. 4 figs.

Bonanos, P.

1992-01-07T23:59:59.000Z

209

Visualization of High Resolution Spatial Mass Spectrometric Data during Acquisition  

SciTech Connect (OSTI)

Mass Spectrometric Imaging (IMS) allows the generation of 2D ion density maps that help visualize molecules present in sections of tissues and cells. The combination of spatial and mass resolution results in large and complex data sets that require powerful and efficient analysis and interpretation. In this paper, a graphical user interface (GUI) that can visualize the large data during data acquisition itself is presented. The program also has the ability to perform processing and analysis of the dataset. The various functions of the GUI including visualization of mass spectra, generation of 2D maps for selected species, manipulation of the heat maps, and peak identification are also presented.

Thomas, Mathew; Heath, Brandi S.; Laskin, Julia; Li, Dongsheng; Liu, Ellen C.; Hui, Katrina L.; Kuprat, Andrew P.; Kleese van Dam, Kerstin; Carson, James P.

2012-08-28T23:59:59.000Z

210

High Resolution Spectroscopy of 12B_Lambda by Electroproduction  

SciTech Connect (OSTI)

An experiment measuring electroproduction of hypernuclei has been performed in Hall A at Jefferson Lab on a $^{12}$C target. In order to increase counting rates and provide unambiguous kaon identification two superconducting septum magnets and a Ring Imaging CHerenkov detector (RICH) were added to the Hall A standard equipment. An unprecedented energy resolution of less than 700 keV FWHM has been achieved. Thus, the observed \\lam{12}{B} spectrum shows for the first time identifiable strength in the core-excited region between the ground-state {\\it s}-wave $\\Lambda$ peak and the 11 MeV {\\it p}-wave $\\Lambda$ peak.

M. Iodice; F. Cusanno; A. Acha; P. Ambrozewicz; K.A. Aniol; P. Baturin; P.Y. Bertin; H. Benaoum; K.I. Blomqvist; W.U. Boeglin; H. Breuer; P. Brindza; P. Byd?zovsk´y; A. Camsonne; C.C. Chang; J.-P. Chen; Seonho Choi; E.A. Chudakov; E. Cisbani; S. Colilli; L. Coman; B.J. Craver; G. De Cataldo; C.W. de Jager; R. De Leo; A.P. Deur; C. Ferdi; R.J. Feuerbach; E. Folts; R. Fratoni; S. Frullani; F. Garibaldi; O. Gayou; F. Giulani; J. Gomez; M. Gricia; J.O. Hansen; D. Hayes; D.W. Higinbotham; T.K. Holmstrom; C.E. Hyde; H.F. Ibrahim; X. Jiang; L.J. Kaufman; K. Kino; B. Kross; L. Lagamba; J.J. LeRose; R.A. Lindgren; M. Lucentini; D.J. Margaziotis; P. Markowitz; S. Marrone; Z.E. Meziani; K. McCormick; R.W. Michaels; D.J. Millener; T. Miyoshi; B. Moffit; P.A. Monaghan; M. Moteabbed; C. Munoz Camacho; S. Nanda; E. Nappi; V.V. Nelyubin; B.E. Norum; Y. Okasyasu; K.D. Paschke; C.F. Perdrisat; E. Piasetzky; V.A. Punjabi; Y. Qiang; B. Raue; P.E. Reimer; J. Reinhold; B. Reitz; R.E. Roche; V.M. Rodriguez; A. Saha; F. Santavenere; A.J. Sarty; J. Segal; A. Shahinyan; J. Singh; S. ? Sirca; R. Snyder; P.H. Solvignon; M. Sotona; R. Subedi; V.A. Sulkosky; T. Suzuki; H. Ueno; P.E. Ulmer; G.M. Urciuoli; P. Veneroni; E. Voutier; B.B. Wojtsekhowski; X. Zheng; and C. Zorn

2007-07-01T23:59:59.000Z

211

High-resolution retinal imaging using adaptive optics and Fourier-domain optical coherence tomography  

DOE Patents [OSTI]

This invention permits retinal images to be acquired at high speed and with unprecedented resolution in three dimensions (4.times.4.times.6 .mu.m). The instrument achieves high lateral resolution by using adaptive optics to correct optical aberrations of the human eye in real time. High axial resolution and high speed are made possible by the use of Fourier-domain optical coherence tomography. Using this system, we have demonstrated the ability to image microscopic blood vessels and the cone photoreceptor mosaic.

Olivier, Scot S. (Livermore, CA); Werner, John S. (Davis, CA); Zawadzki, Robert J. (Sacramento, CA); Laut, Sophie P. (Pasedena, CA); Jones, Steven M. (Livermore, CA)

2010-09-07T23:59:59.000Z

212

High-power single mode solid state laser with short wide unstable cavity: Misprints  

E-Print Network [OSTI]

1 High-power single mode solid state laser with short wide unstable cavity: Misprints D. Kouznetsov. Kouznetsov, J.-F. Bisson, K. Takaichi K. Ueda. High-power single mode solid state laser with short wide

Kouznetsov, Dmitrii

213

High power KrF laser development at Los Alamos  

SciTech Connect (OSTI)

The objective of the high power laser development program at Los Alamos is to appraise the potential of the KrF laser as a driver for inertial confinement fusion (ICF), ultimately at energy levels that will produce high target gain (gain of order 100). A KrF laser system prototype, the 10-kJ Aurora laser, which is nearing initial system operation, will serve as a feasibility demonstration of KrF technology and system design concepts appropriate to large scale ICF driver systems. The issues of affordable cost, which is a major concern for all ICF drivers now under development, and technology scaling are also being examined. It is found that, through technology advances and component cost reductions, the potential exists for a KrF driver to achieve a cost goal in the neighborhood of $100 per joule. The authors suggest that the next step toward a multimegajoule laboratory microfusion facility (LMF) is an ''Intermediate Driver'' facility in the few hundred kilojoule to one megajoule range, which will help verify the scaling of driver technology and cost to an LMF size. An Intermediate Driver facility would also increase the confidence in the estimates of energy needed for an LMF and would reduce the risk in target performance. 5 refs., 4 figs., 1 tab.

McDonald, T.; Cartwright, D.; Fenstermacher, C.; Figueira, J.; Goldstone, P.; Harris, D.; Mead, W.; Rosocha, L.

1988-01-01T23:59:59.000Z

214

High Resolution PET with 250 micrometer LSO Detectors and Adaptive Zoom  

SciTech Connect (OSTI)

There have been impressive improvements in the performance of small-animal positron emission tomography (PET) systems since their first development in the mid 1990s, both in terms of spatial resolution and sensitivity, which have directly contributed to the increasing adoption of this technology for a wide range of biomedical applications. Nonetheless, current systems still are largely dominated by the size of the scintillator elements used in the detector. Our research predicts that developing scintillator arrays with an element size of 250 {micro}m or smaller will lead to an image resolution of 500 {micro}m when using 18F- or 64Cu-labeled radiotracers, giving a factor of 4-8 improvement in volumetric resolution over the highest resolution research systems currently in existence. This proposal had two main objectives: (i) To develop and evaluate much higher resolution and efficiency scintillator arrays that can be used in the future as the basis for detectors in a small-animal PET scanner where the spatial resolution is dominated by decay and interaction physics rather than detector size. (ii) To optimize one such high resolution, high sensitivity detector and adaptively integrate it into the existing microPET II small animal PET scanner as a 'zoom-in' detector that provides higher spatial resolution and sensitivity in a limited region close to the detector face. The knowledge gained from this project will provide valuable information for building future PET systems with a complete ring of very high-resolution detector arrays and also lay the foundations for utilizing high-resolution detectors in combination with existing PET systems for localized high-resolution imaging.

Cherry, Simon R.; Qi, Jinyi

2012-01-08T23:59:59.000Z

215

Solidi cation of a high-Reynolds-number ow in laser percussion drilling  

E-Print Network [OSTI]

Solidi#12;cation of a high-Reynolds-number ow in laser percussion drilling W. R. Smith y and R. M laser percussion drilling. 1 Introduction Laser percussion drilling is used to machine gas turbine with conventional mechanical drills. The term percussion refers to the repeated operation of the laser in short

Eindhoven, Technische Universiteit

216

1. INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. HIGH-ACCURACY LASER POWER AND ENERGY METER CALIBRATION SYSTEM . . . . . . . . 2  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 2. HIGH-ACCURACY LASER POWER AND ENERGY METER CALIBRATION SYSTEM . . . . . . . . 2 2.1 Calibration

217

High resolution ion Doppler spectroscopy at Prairie View Rotamak  

SciTech Connect (OSTI)

A fast ion Doppler spectroscopy (IDS) diagnostic system is installed on the Prairie View Rotamak to measure ion temperature and plasma flow. The diagnostic employs a single channel photomultiplier tube and a Jarrell-Ash 50 monochromator with a diffraction grating line density of 1180 lines/mm, which allows for first order spectra of 200-600 nm. The motorized gear of the monochromator allows spectral resolution of 0.01 nm. Equal IDS measurements are observed for various impurity emission lines of which carbon lines exhibit stronger intensities. Furthermore, the diagnostics is examined in an experiment where plasma experiences sudden disruption and quick recovery. In this case, the IDS measurements show {approx}130% increase in ion temperature. Flow measurements are shown to be consistent with plasma rotation.

Houshmandyar, Saeid; Yang Xiaokang [Solar Observatory Department, Prairie View A and M University, Prairie View, Texas 77446 (United States); Magee, Richard [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

2012-10-15T23:59:59.000Z

218

A High Resolution Monolithic Crystal, DOI, MR Compatible, PET Detector  

SciTech Connect (OSTI)

The principle objective of this proposal is to develop a positron emission tomography (PET) detector with depth-of-interaction (DOI) positioning capability that will achieve state of the art spatial resolution and sensitivity performance for small animal PET imaging. When arranged in a ring or box detector geometry, the proposed detector module will support <1 mm3 image resolution and >15% absolute detection efficiency. The detector will also be compatible with operation in a MR scanner to support simultaneous multi-modality imaging. The detector design will utilize a thick, monolithic crystal scintillator readout by a two-dimensional array of silicon photomultiplier (SiPM) devices using a novel sensor on the entrance surface (SES) design. Our hypothesis is that our single-ended readout SES design will provide an effective DOI positioning performance equivalent to more expensive dual-ended readout techniques and at a significantly lower cost. Our monolithic crystal design will also lead to a significantly lower cost system. It is our goal to design a detector with state of the art performance but at a price point that is affordable so the technology can be disseminated to many laboratories. A second hypothesis is that using SiPM arrays, the detector will be able to operate in a MR scanner without any degradation in performance to support simultaneous PET/MR imaging. Having a co-registered MR image will assist in radiotracer localization and may also be used for partial volume corrections to improve radiotracer uptake quantitation. The far reaching goal of this research is to develop technology for medical research that will lead to improvements in human health care.

Robert S Miyaoka

2012-03-06T23:59:59.000Z

219

A high performance R-D readout circuitry for lg resolution microaccelerometers  

E-Print Network [OSTI]

A high performance R-D readout circuitry for lg resolution microaccelerometers _Ilker E. Ocak an adjustable sensitivity up to 8 V/g with a noise level of 4.8 lg/HHz in open-loop. Keywords Sigma precision accelerometers with micro-g (lg, g = 9.8 m/s2 ) resolution have many applications, including

Akin, Tayfun

220

High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens  

E-Print Network [OSTI]

High Resolution Backside Imaging and Thermography using a Numerical Aperture Increasing Lens Shawn inspection alone, it is necessary to develop techniques, such as thermography, with the capability ­solid immersion lens microscopy and thermography. Standard non-contact optical resolution is limited

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Highly ecient kinetic resolution of 2-cyclohexenyl acetate in Pd-catalyzed allylic alkylation  

E-Print Network [OSTI]

Highly ecient kinetic resolution of 2-cyclohexenyl acetate in Pd-catalyzed allylic alkylation James resolution of 2-cyclohexenyl acetate was observed during alkylation. In addition, the reactivity and enantioselectivity showed a strong dependence on the acetate salt with the BSA/MOAc (M=alkali metal) base system

Zhang, Xumu

222

NCEP Products Available to Distribute to CONDUIT High-Resolution Window Forecast System (HIRESW) Full  

E-Print Network [OSTI]

NCEP Products Available to Distribute to CONDUIT Phase 1 High-Resolution Window Forecast System Ocean Forecast System (RTOFS) Full Description Product Location The RTOFS for the North Atlantic resolution nest Hurricane Weather Research and Forecast (HWRF) system Full Description Product Location (hwrf

223

A Warm Near-Infrared High-Resolution Spectrograph with Very High Throughput (WINERED)  

E-Print Network [OSTI]

WINERED is a newly built high-efficiency (throughput$ > 25-30\\%$) and high-resolution spectrograph customized for short NIR bands at 0.9-1.35 ${\\rm \\mu}$m. WINERED is equipped with ambient temperature optics and a cryogenic camera using a 1.7 ${\\rm \\mu}$m cut-off HgCdTe HAWAII-2RG array detector. WINERED has two grating modes: one with a conventional reflective echelle grating (R$\\sim$28,300), which covers 0.9-1.35 $\\mu$m simultaneously, the other with ZnSe or ZnS immersion grating (R$\\sim$100,000). We have completed the development of WINERED except for the immersion grating, and started engineering and science observations at the Nasmyth platform of the 1.3 m Araki Telescope at Koyama Astronomical Observatory of Kyoto-Sangyo University in Japan. We confirmed that the spectral resolution ($R\\sim$ 28,300) and the throughput ($>$ 40\\% w/o telescope/atmosphere/array QE) meet our specifications. We measured ambient thermal backgrounds (e.g., 0.06 ${\\rm [e^{-}/sec/pixel]}$ at 287 K), which are roughly consistent ...

Kondo, Sohei; Kobayashi, Naoto; Yasui, Chikako; Mito, Hiroyuki; Fukue, Kei; Nakanishi, Kenshi; Kawanishi, Takafumi; Nakaoka, Tetsuya; Otsubo, Shogo; Kinoshita, Masaomi; Kitano, Ayaka; Hamano, Satoshi; Mizumoto, Misaki; Yamamoto, Ryo; Izumi, Natsuko; Matsunaga, Noriyuki; Kawakita, Hideyo

2015-01-01T23:59:59.000Z

224

Development of high-spatial and high-mass resolution mass spectrometric imaging (MSI) and its application to the study of small metabolites and endogenous molecules of plants  

SciTech Connect (OSTI)

High-spatial and high-mass resolution laser desorption ionization (LDI) mass spectrometric (MS) imaging technology was developed for the attainment of MS images of higher quality containing more information on the relevant cellular and molecular biology in unprecedented depth. The distribution of plant metabolites is asymmetric throughout the cells and tissues, and therefore the increase in the spatial resolution was pursued to reveal the localization of plant metabolites at the cellular level by MS imaging. For achieving high-spatial resolution, the laser beam size was reduced by utilizing an optical fiber with small core diameter (25 ?m) in a vacuum matrix-assisted laser desorption ionization-linear ion trap (vMALDI-LTQ) mass spectrometer. Matrix application was greatly improved using oscillating capillary nebulizer. As a result, single cell level spatial resolution of ~ 12 ?m was achieved. MS imaging at this high spatial resolution was directly applied to a whole Arabidopsis flower and the substructures of an anther and single pollen grains at the stigma and anther were successfully visualized. MS imaging of high spatial resolution was also demonstrated to the secondary roots of Arabidopsis thaliana and a high degree of localization of detected metabolites was successfully unveiled. This was the first MS imaging on the root for molecular species. MS imaging with high mass resolution was also achieved by utilizing the LTQ-Orbitrap mass spectrometer for the direct identification of the surface metabolites on the Arabidopsis stem and root and differentiation of isobaric ions having the same nominal mass with no need of tandem mass spectrometry (MS/MS). MS imaging at high-spatial and high-mass resolution was also applied to cer1 mutant of the model system Arabidopsis thaliana to demonstrate its usefulness in biological studies and reveal associated metabolite changes in terms of spatial distribution and/or abundances compared to those of wild-type. The spatial distribution of targeted metabolites, mainly waxes and flavonoids, was systematically explored on various organs, including flowers, leaves, stems, and roots at high spatial resolution of ~ 12-50 ?m and the changes in the abundance level of these metabolites were monitored on the cer1 mutant with respect to the wild-type. This study revealed the metabolic biology of CER1 gene on each individual organ level with very detailed high spatial resolution. The separate MS images of isobaric metabolites, i.e. C29 alkane vs. C28 aldehyde could be constructed on both genotypes from MS imaging at high mass resolution. This allows tracking of abundance changes for those compounds along with the genetic mutation, which is not achievable with low mass resolution mass spectrometry. This study supported previous hypothesis of molecular function of CER1 gene as aldehyde decarbonylase, especially by displaying hyper accumulation of aldehydes and C30 fatty acid and decrease in abundance of alkanes and ketones in several plant organs of cer1 mutant. The scope of analytes was further directed toward internal cell metabolites from the surface metabolites of the plant. MS profiling and imaging of internal cell metabolites were performed on the vibratome section of Arabidopsis leaf. Vibratome sectioning of the leaf was first conducted to remove the surface cuticle layer and it was followed by enzymatic treatment of the section to induce the digestion of primary cell walls, middle lamella, and expose the internal cells underneath to the surface for detection with the laser by LDI-MS. The subsequent MS imaging onto the enzymatically treated vibratome section allowed us to map the distribution of the metabolites in the internal cell layers, linolenic acid (C18:3 FA) and linoleic acid (C18:2 FA). The development of an assay for relative quantification of analytes at the single subcellular/organelle level by LDI-MS imaging was attempted and both plausibility and significant obstacles were seen. As a test system, native plant organelle, chloroplasts isolated from the spinach leaves were used

Jun, Ji Hyun

2011-11-30T23:59:59.000Z

225

automatic high resolution: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

with its Sun 3 workstations, Sun Melvin, Stephen 24 Automatic keywording of High Energy Physics CERN Preprints Summary: Bibliographic databases were developed from the...

226

High energy laser optics manufacturing: a preliminary study  

SciTech Connect (OSTI)

This report presents concepts and methods, major conclusions, and major recommendations concerning the fabrication of high energy laser optics (HELO) that are to be machined by the Large Optics Diamond Turning Machine (LODTM) at the Lawrence Livermore National Laboratory (LLNL). Detailed discussions of concepts and methods proposed for metrological operations, polishing of reflective surfaces, mounting of optical components, construction of mirror substrates, and applications of coatings are included.

Baird, E.D.

1980-07-01T23:59:59.000Z

227

High average power magnetic modulator for metal vapor lasers  

DOE Patents [OSTI]

A three-stage magnetic modulator utilizing magnetic pulse compression designed to provide a 60 kV pulse to a copper vapor laser at a 4.5 kHz repetition rate is disclosed. This modulator operates at 34 kW input power. The circuit includes a step up auto transformer and utilizes a rod and plate stack construction technique to achieve a high packing factor.

Ball, Don G. (Livermore, CA); Birx, Daniel L. (Oakley, CA); Cook, Edward G. (Livermore, CA); Miller, John L. (Livermore, CA)

1994-01-01T23:59:59.000Z

228

Design of electronics for a high-resolution, multi-material, and modular 3D printer  

E-Print Network [OSTI]

Electronics for a high-resolution, multi-material, and modular 3D printer were designed and implemented. The driver for a piezoelectric inkjet print head can fire its nozzles with one of three droplet sizes ranging from 6 ...

Kwan, Joyce G

2013-01-01T23:59:59.000Z

229

A machine learning model of Manhattan air pollution at high spatial resolution  

E-Print Network [OSTI]

A machine-learning model was created to predict air pollution at high spatial resolution in Manhattan, New York using taxi trip data. Urban air pollution increases morbidity and mortality through respiratory and cardiovascular ...

Keeler, Rachel H. (Rachel Heiden)

2014-01-01T23:59:59.000Z

230

Perfusion-Based High-Resolution Functional Imaging in the Human Brain at 7 Tesla  

E-Print Network [OSTI]

Perfusion-Based High-Resolution Functional Imaging in the Human Brain at 7 Tesla Josef Pfeuffer and reperfusion, blood flow deficits in Alzheimer's disease, HIV-cognitive motor complex dementia, and epilepsy (5

231

High-Resolution Characterization of Reservoir Heterogeneity and Connectivity in Clastic Environments  

E-Print Network [OSTI]

This study developed new concepts and interpretative methods for mapping reservoir heterogeneity and connectivity of a fault controlled Wilcox clastic reservoir in Texas, USA. The application of high-resolution seismic enhancement in this study...

Hull, Thomas Frederick

2011-10-21T23:59:59.000Z

232

The genetic architecture of Down syndrome phenotypes revealed by high-resolution analysis  

E-Print Network [OSTI]

The genetic architecture of Down syndrome phenotypes revealed by high-resolution analysis of human, CA, and approved May 29, 2009 (received for review December 30, 2008) Down syndrome (DS), or trisomy

Gerstein, Mark

233

Fabricating BRDFs at High Spatial Resolution Using Wave Optics Anat Levin1  

E-Print Network [OSTI]

spatially varying reflectance at a high resolution of up to 220dpi , orders of magnitude greater than such as a BRDF chart [Ren et al. 2011] and a planar light probe [Alldrin and Kriegman. 2006]. Recent attempts

234

Ion implantation for figure correction of high-resolution x-ray telescope mirrors  

E-Print Network [OSTI]

Fabricating mirrors for future high-resolution, large-aperture x-ray telescopes continues to challenge the x-ray astronomy instrumentation community. Building a large-aperture telescope requires thin, lightweight mirrors; ...

Chalifoux, Brandon D

2014-01-01T23:59:59.000Z

235

High-resolution three-dimensional optical coherence tomography imaging of kidney microanatomy ex vivo  

E-Print Network [OSTI]

Optical coherence tomography (OCT) is an emerging medical imaging technology that enables high-resolution, noninvasive, cross-sectional imaging of microstructure in biological tissues in situ and in real time. When combined ...

Chen, Yu

236

High resolution CMRO2 in visual cortex of macaca mulatta Y. Bohraus1  

E-Print Network [OSTI]

the contribution of the vascular system and neural energy consumption. Measuring CMRO2 allows one to determine with previous MR and PET results such as reviewed in [7]. In conclusion, we showed that high resolution CMRO2

237

TOWARDS AN IMPROVED HIGH RESOLUTION GLOBAL LONG-TERM SOLAR RESOURCE DATABASE  

E-Print Network [OSTI]

TOWARDS AN IMPROVED HIGH RESOLUTION GLOBAL LONG- TERM SOLAR RESOURCE DATABASE Paul W. Stackhouse and test an improved production system that will enable the longest-term global solar resource database

Perez, Richard R.

238

HIGH-RESOLUTION EPR AND PIEZOSPECTROSCOPY STUDIES OF THE LITHIUM-OXYGEN DONOR IN GERMANIUM  

E-Print Network [OSTI]

LCL-8429 HIGH-RESOLUTION EPR AND PIEZOSPECTROSCOPY STUDIESLBL-8429 •^^. -r-i^irjION EPR AND PIEZOSPECTROSCOPY STUDIESBOO X V X. X. X. X x V N The EPR and IR spectra of Li-0 can

Haller, E.E.

2011-01-01T23:59:59.000Z

239

SEX DIFFERENCES IN THE HUMAN CONNECTOME: 4-TESLA HIGH ANGULAR RESOLUTION DIFFUSION IMAGING (HARDI)  

E-Print Network [OSTI]

SEX DIFFERENCES IN THE HUMAN CONNECTOME: 4-TESLA HIGH ANGULAR RESOLUTION DIFFUSION IMAGING (HARDI diffusion imaging at 4 Tesla, we scanned 234 young adult twins and siblings (mean age: 23.4 ± 2.0 SD years

Thompson, Paul

240

NESTED HIGH RESOLUTION SIMULATION AND LIDAR VALIDATION OF A LAND BREEZE CIRCULATION  

E-Print Network [OSTI]

NESTED HIGH RESOLUTION SIMULATION AND LIDAR VALIDATION OF A LAND BREEZE CIRCULATION by GIJS DE BOER local forcing. A wide range of scales is simulated using the nesting capability of the University

Eloranta, Edwin W.

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Untangling the contributions of image charge and laser profile for optimal photoemission of high-brightness electron beams  

SciTech Connect (OSTI)

Using our model for the simulation of photoemission of high brightness electron beams, we investigate the virtual cathode physics and the limits to spatio-temporal and spectroscopic resolution originating from the image charge on the surface and from the profile of the exciting laser pulse. By contrasting the effect of varying surface properties (leading to expanding or pinned image charge), laser profiles (Gaussian, uniform, and elliptical), and aspect ratios (pancake- and cigar-like) under different extraction field strengths and numbers of generated electrons, we quantify the effect of these experimental parameters on macroscopic pulse properties such as emittance, brightness (4D and 6D), coherence length, and energy spread. Based on our results, we outline optimal conditions of pulse generation for ultrafast electron microscope systems that take into account constraints on the number of generated electrons and on the required time resolution.

Portman, J.; Zhang, H.; Makino, K.; Ruan, C. Y.; Berz, M.; Duxbury, P. M. [Physics and Astronomy Department, Michigan State University, East Lansing, Michigan 48824 (United States)

2014-11-07T23:59:59.000Z

242

Investigating high speed phenomena in laser plasma interactions using dilation x-ray imager (invited)  

SciTech Connect (OSTI)

The DIlation X-ray Imager (DIXI) is a new, high-speed x-ray framing camera at the National Ignition Facility (NIF) sensitive to x-rays in the range of ?2–17 keV. DIXI uses the pulse-dilation technique to achieve a temporal resolution of less than 10 ps, a ?10× improvement over conventional framing cameras currently employed on the NIF (?100 ps resolution), and otherwise only attainable with 1D streaked imaging. The pulse-dilation technique utilizes a voltage ramp to impart a velocity gradient on the signal-bearing electrons. The temporal response, spatial resolution, and x-ray sensitivity of DIXI are characterized with a short x-ray impulse generated using the COMET laser facility at Lawrence Livermore National Laboratory. At the NIF a pinhole array at 10 cm from target chamber center (tcc) projects images onto the photocathode situated outside the NIF chamber wall with a magnification of ?64×. DIXI will provide important capabilities for warm-dense-matter physics, high-energy-density science, and inertial confinement fusion, adding important capabilities to temporally resolve hot-spot formation, x-ray emission, fuel motion, and mix levels in the hot-spot at neutron yields of up to 10{sup 17}. We present characterization data as well as first results on electron-transport phenomena in buried-layer foil experiments.

Nagel, S. R., E-mail: nagel7@llnl.gov; Bell, P. M.; Bradley, D. K.; Ayers, M. J.; Piston, K.; Felker, B. [Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States); Hilsabeck, T. J.; Kilkenny, J. D.; Chung, T.; Sammuli, B. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States); Hares, J. D.; Dymoke-Bradshaw, A. K. L. [Kentech Instruments Ltd., Wallingford, Oxfordshire OX10 (United Kingdom)

2014-11-15T23:59:59.000Z

243

Optic for an endoscope/borescope having high resolution and narrow field of view  

DOE Patents [OSTI]

An optic having optimized high spatial resolution, minimal nonlinear magnification distortion while at the same time having a limited chromatic focal shift or chromatic aberrations. The optic located at the distal end of an endoscopic inspection tool permits a high resolution, narrow field of view image for medical diagnostic applications, compared to conventional optics for endoscopic instruments which provide a wide field of view, low resolution image. The image coverage is over a narrow (<20 degrees) field of view with very low optical distortion (<5% pin cushion or barrel distortion. The optic is also optimized for best color correction as well as to aid medical diagnostics.

Stone, Gary F.; Trebes, James E.

2003-10-28T23:59:59.000Z

244

High Resolution PV Power Modeling for Distribution Circuit Analysis  

SciTech Connect (OSTI)

NREL has contracted with Clean Power Research to provide 1-minute simulation datasets of PV systems located at three high penetration distribution feeders in the service territory of Southern California Edison (SCE): Porterville, Palmdale, and Fontana, California. The resulting PV simulations will be used to separately model the electrical circuits to determine the impacts of PV on circuit operations.

Norris, B. L.; Dise, J. H.

2013-09-01T23:59:59.000Z

245

High performance tunnel injection quantum dot comb laser  

SciTech Connect (OSTI)

A high-speed multiwavelength quantum dot comb laser, grown by molecular beam epitaxy, is demonstrated. The device is characterized with a 75.9 nm (full width at half maximum) and a 91.4 nm (DELTA{sub -15dB}) wide lasing spectrum. There are 105 and 185 simultaneously emitted longitudinal modes with a maximum channel intensity nonuniformity of less than 3 dB in the spectral range of 1231-1252 nm and 1274-1311 nm, respectively, for a laser with 1040 mum cavity length. The channel spacing can be tuned with cavity length and remains invariant in the temperature range of 300-323 K. The small signal modulation bandwidth is 7.5 GHz.

Lee, C.-S.; Guo Wei; Basu, Debashish; Bhattacharya, Pallab [Department of Electrical Engineering and Computer Science, Solid State Electronics Laboratory, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States)

2010-03-08T23:59:59.000Z

246

High-Energy, Pulsed-Laser Diagnostics for Real-Time Measurements...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

Energy, Pulsed-Laser Diagnostics for Real-Time Measurements of Reciprocating Engine PM Emissions High-Energy, Pulsed-Laser Diagnostics for Real-Time Measurements of Reciprocating...

247

High energy conversion efficiency in laser-proton acceleration by controlling laser-energy deposition onto thin foil targets  

SciTech Connect (OSTI)

An all-optical approach to laser-proton acceleration enhancement is investigated using the simplest of target designs to demonstrate application-relevant levels of energy conversion efficiency between laser and protons. Controlled deposition of laser energy, in the form of a double-pulse temporal envelope, is investigated in combination with thin foil targets in which recirculation of laser-accelerated electrons can lead to optimal conditions for coupling laser drive energy into the proton beam. This approach is shown to deliver a substantial enhancement in the coupling of laser energy to 5–30?MeV protons, compared to single pulse irradiation, reaching a record high 15% conversion efficiency with a temporal separation of 1 ps between the two pulses and a 5??m-thick Au foil. A 1D simulation code is used to support and explain the origin of the observation of an optimum pulse separation of ?1 ps.

Brenner, C. M. [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Robinson, A. P. L.; Markey, K.; Scott, R. H. H.; Lancaster, K. L.; Musgrave, I. O.; Spindloe, C.; Winstone, T.; Wyatt, D.; Neely, D. [Central Laser Facility, STFC, Rutherford Appleton Laboratory, Didcot, Oxon OX11 0QX (United Kingdom); Gray, R. J.; McKenna, P. [Department of Physics, SUPA, University of Strathclyde, Glasgow G4 0NG (United Kingdom); Rosinski, M.; Badziak, J.; Wolowski, J. [Institute of Plasma Physics and Laser Microfusion, 00-908 Warsaw (Poland); Deppert, O. [Institut für Kernphysik, Technische Universität Darmstadt, 64289 Darmstadt (Germany); Batani, D. [Dipartimento di Fisica G. Occhialini, Universita di Milano Bicocca, 20126 Milan (Italy); Davies, J. R. [Laboratory for Laser Energetics, Fusion Science Center for Extreme States of Matter, University of Rochester, Rochester, New York 14623 (United States); Hassan, S. M.; Tatarakis, M. [Department of Electronics Engineering, Centre for Plasma Physics and Lasers, 73133 Chania, 74100 Rethymno, Crete (Greece); and others

2014-02-24T23:59:59.000Z

248

Two-beam ultrabroadband coherent anti-Stokes Raman spectroscopy for high resolution gas-phase multiplex imaging  

SciTech Connect (OSTI)

We propose and develop a method for wideband coherent anti-Stokes Raman spectroscopy (CARS) in the gas phase and demonstrate the single-shot measurement of N{sub 2}, H{sub 2}, CO{sub 2}, O{sub 2}, and CH{sub 4}. Pure-rotational and vibrational O-, Q-, and S- branch spectra are collected simultaneously, with high spectral and spatial resolution, and within a single-laser-shot. The relative intensity of the rotational and vibrational signals can be tuned arbitrarily using polarization techniques. The ultrashort 7 fs pump and Stokes pulses are automatically overlapped temporally and spatially using a two-beam CARS technique, and the crossed probe beam allows for excellent spatial sectioning of the probed location.

Bohlin, Alexis; Kliewer, Christopher J., E-mail: cjkliew@sandia.gov [Combustion Research Facility, Sandia National Laboratories, Livermore, California 94550 (United States)

2014-01-20T23:59:59.000Z

249

Overshooting Convection from High-resolution NEXRAD Observations  

E-Print Network [OSTI]

employs the difference between 6-7 µm water vapor absorption and ?11 µm infrared window channel brightness temper- ature for overshooting convection detection (e.g., Fritz and Laszlo, 1993; Ackerman, 2 1996; Schmetz et al., 1997; Setvak et al., 2007... and in Radiative Forcing, pp. 129–234, Cambridge University Press, Cambridge, UK. Fritz, S., and I. Laszlo (1993), Detection of water vapor in the stratosphere over very high clouds in the tropics, J. Geophys. Res., 98 (D12), 22,959–22,967. 32 Fromm, M. D., and R...

Solomon, David

2014-01-09T23:59:59.000Z

250

EECS 598 Special Topics 005: Laser Plasma Diagnostics High power laser pulses are used to both create and diagnose high-energy  

E-Print Network [OSTI]

EECS 598 Special Topics 005: Laser Plasma Diagnostics High power laser pulses are used to both to relativistic-intensity femtosecond pulses. We will explore the diagnostics used to characterize high-energy density plasmas through optical and other radiation measurements as well as backlighting techniques. Other

Sarabandi, Kamal

251

High power laser heating of low absorption materials  

SciTech Connect (OSTI)

A model is presented and confirmed experimentally that explains the anomalous behavior observed in continuous wave (CW) excitation of thermally isolated optics. Distributed Bragg Reflector (DBR) high reflective optical thin film coatings of HfO{sub 2} and SiO{sub 2} were prepared with a very low absorption, about 7?ppm, measured by photothermal common-path interferometry. When illuminated with a 17?kW CW laser for 30 s, the coatings survived peak irradiances of 13?MW/cm{sup 2}, on 500??m diameter spot cross sections. The temperature profile of the optical surfaces was measured using a calibrated thermal imaging camera for illuminated spot sizes ranging from 500??m to 5?mm; about the same peak temperatures were recorded regardless of spot size. This phenomenon is explained by solving the heat equation for an optic of finite dimensions and taking into account the non-idealities of the experiment. An analytical result is also derived showing the relationship between millisecond pulse to CW laser operation where (1) the heating is proportional to the laser irradiance (W/m{sup 2}) for millisecond pulses, (2) the heating is proportional to the beam radius (W/m) for CW, and (3) the heating is proportional to W/m??tan{sup ?1}(?(t)/m) in the transition region between the two.

Olson, K.; Talghader, J., E-mail: joey@umn.edu [Electrical Engineering, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Ogloza, A. [Naval Postgraduate School, 1 University Cir, Monterey, California 93943 (United States); Thomas, J. [Electro Optics Center, Pennsylvania State University, 222 Northpointe Blvd., Freeport, Pennsylvania 16229 (United States)

2014-09-28T23:59:59.000Z

252

High resolution mass spectrometry method and system for analysis of whole proteins and other large molecules  

DOE Patents [OSTI]

A matrix assisted laser desorption/ionization (MALDI) method and related system for analyzing high molecular weight analytes includes the steps of providing at least one matrix-containing particle inside an ion trap, wherein at least one high molecular weight analyte molecule is provided within the matrix-containing particle, and MALDI on the high molecular weight particle while within the ion trap. A laser power used for ionization is sufficient to completely vaporize the particle and form at least one high molecular weight analyte ion, but is low enough to avoid fragmenting the high molecular weight analyte ion. The high molecular weight analyte ion is extracted out from the ion trap, and is then analyzed using a detector. The detector is preferably a pyrolyzing and ionizing detector.

Reilly, Peter T. A. (Knoxville, TN) [Knoxville, TN; Harris, William A. (Naperville, IL) [Naperville, IL

2010-03-02T23:59:59.000Z

253

A multi-purpose modular system for high-resolution microscopy at high hydrostatic pressure  

E-Print Network [OSTI]

We have developed a modular system for high-resolution microscopy at high hydrostatic pressure. The system consists of a pressurised cell of volume ~100 microlitres, a temperature controlled holder, a ram and a piston. We have made each of these components in several versions which can be interchanged to allow a wide range of applications. Here, we report two pressure cells with pressure ranges 0.1-700MPa and 0.1-100MPa, which can be combined with hollow or solid rams and pistons. Our system is designed to work with fluorescent samples (using a confocal or epifluorescence microscope), but also allows for transmitted light microscopy via the hollow ram and piston. The system allows precise control of pressure and temperature [-20-70C], as well as rapid pressure quenching. We demonstrate its performance and versatility with two applications: time-resolved imaging of colloidal phase transitions caused by pressure changes between 0.1MPa and 101MPa, and imaging the growth of Escherichia coli bacteria at 50MPa. We ...

Vass, Hugh; Herzig, Eva M; Ward, F Bruce; Clegg, Paul S; Allen, Rosalind J

2009-01-01T23:59:59.000Z

254

High resolution 3D insider detection and tracking.  

SciTech Connect (OSTI)

Vulnerability analysis studies show that one of the worst threats against a facility is that of an active insider during an emergency evacuation. When a criticality or other emergency alarm occurs, employees immediately proceed along evacuation routes to designated areas. Procedures are then implemented to account for all material, classified parts, etc. The 3-Dimensional Video Motion Detection (3DVMD) technology could be used to detect and track possible insider activities during alarm situations, as just described, as well as during normal operating conditions. The 3DVMD technology uses multiple cameras to create 3-dimensional detection volumes or zones. Movement throughout detection zones is tracked and high-level information, such as the number of people and their direction of motion, is extracted. In the described alarm scenario, deviances of evacuation procedures taken by an individual could be immediately detected and relayed to a central alarm station. The insider could be tracked and any protected items removed from the area could be flagged. The 3DVMD technology could also be used to monitor such items as machines that are used to build classified parts. During an alarm, detections could be made if items were removed from the machine. Overall, the use of 3DVMD technology during emergency evacuations would help to prevent the loss of classified items and would speed recovery from emergency situations. Further security could also be added by analyzing tracked behavior (motion) as it corresponds to predicted behavior, e.g., behavior corresponding with the execution of required procedures. This information would be valuable for detecting a possible insider not only during emergency situations, but also during times of normal operation.

Nelson, Cynthia Lee

2003-09-01T23:59:59.000Z

255

Dedicated mobile high resolution prostate PET imager with an insertable transrectal probe  

DOE Patents [OSTI]

A dedicated mobile PET imaging system to image the prostate and surrounding organs. The imaging system includes an outside high resolution PET imager placed close to the patient's torso and an insertable and compact transrectal probe that is placed in close proximity to the prostate and operates in conjunction with the outside imager. The two detector systems are spatially co-registered to each other. The outside imager is mounted on an open rotating gantry to provide torso-wide 3D images of the prostate and surrounding tissue and organs. The insertable probe provides closer imaging, high sensitivity, and very high resolution predominately 2D view of the prostate and immediate surroundings. The probe is operated in conjunction with the outside imager and a fast data acquisition system to provide very high resolution reconstruction of the prostate and surrounding tissue and organs.

Majewski, Stanislaw (Yorktown, VA); Proffitt, James (Newport News, VA)

2010-12-28T23:59:59.000Z

256

High resolution x-ray and gamma ray imaging using diffraction lenses with mechanically bent crystals  

DOE Patents [OSTI]

A method for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation is provided. High quality mechanically bent diffracting crystals of 0.1 mm radial width are used for focusing the radiation and directing the radiation to an array of detectors which is used for analyzing their addition to collect data as to the location of the source of radiation. A computer is used for converting the data to an image. The invention also provides for the use of a multi-component high resolution detector array and for narrow source and detector apertures.

Smither, Robert K. (Hinsdale, IL)

2008-12-23T23:59:59.000Z

257

High-speed high-resolution plasma spectroscopy using spatial-multiplex coherence imaging techniques  

E-Print Network [OSTI]

, laser Thomson scattering and infrared thermography [1­3] . When the spectral content of a scene can, thermography, bremsstrahlung, Thomson scattering), it is often the case that these parameters can be recovered

Howard, John

258

Experimental astrophysics with high power lasers and Z pinches  

SciTech Connect (OSTI)

With the advent of high energy density (HED) experimental facilities, such as high-energy lasers and fast Z-pinch, pulsed-power facilities, mm-scale quantities of matter can be placed in extreme states of density, temperature, and/or velocity. This has enabled the emergence of a new class of experimental science, HED laboratory astrophysics, wherein the properties of matter and the processes that occur under extreme astrophysical conditions can be examined in the laboratory. Areas particularly suitable to this class of experimental astrophysics include the study of opacities relevant to stellar interiors; equations of state relevant to planetary interiors; strong shock driven nonlinear hydrodynamics and radiative dynamics, relevant to supernova explosions and subsequent evolution; protostellar jets and high Mach-number flows; radiatively driven molecular clouds and nonlinear photoevaporation front dynamics; and photoionized plasmas relevant to accretion disks around compact objects, such as black holes and neutron stars.

Remington, B A; Drake, R P; Ryutov, D D

2004-12-10T23:59:59.000Z

259

The Universe Viewed in Gamma-Rays 1 High-Resolution Cherenkov Telescopes for the Observation  

E-Print Network [OSTI]

The Universe Viewed in Gamma-Rays 1 High-Resolution Cherenkov Telescopes for the Observation of High-Energy Gamma Rays F.Kajino, T.Wasio, I.Tada, T.Oda, E.Choi, S.Hayashi, M.Sakata, Y optics and camera used for recent Cherenkov telescopes is usually limited to be only about 0.1 degree

Enomoto, Ryoji

260

High power CW dye laser emission around 888 nm M. Leduc and G. Trenec  

E-Print Network [OSTI]

355 High power CW dye laser emission around 888 nm M. Leduc and G. Trenec Laboratoire de report a maximum output power of 1.5 W at 888 nm from a HITC jet stream dye laser pumped by a Kr+ laser above previously reported results. Good stability of the dye solution is observed over months

Paris-Sud XI, Université de

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

CONSTRAINTS ON LASER-DRIVEN ACCELERATORS FOR A HIGH-ENERGY LINEAR COLLIDER*  

E-Print Network [OSTI]

CONSTRAINTS ON LASER-DRIVEN ACCELERATORS FOR A HIGH-ENERGY LINEAR COLLIDER* J.S. Wurtele and AV on 1 TeV) are applied to free-space laser and laser/plasma accelerators. It is shown that the requirements impose very severe constraints upon the new accelerators-- so severe, that it seems unlikely

Wurtele, Jonathan

262

High-precision CO2 isotopologue spectrometer with a difference-frequency-generation laser source  

E-Print Network [OSTI]

High-precision CO2 isotopologue spectrometer with a difference-frequency-generation laser source A precision laser spectrometer for the detection of CO2 isotopes is reported. The spectrometer measures the fundamental absorption signatures of 13 C and 12 C isotopes in CO2 at 4.32 m using a tunable mid-IR laser

263

Monte Carlo calculations of pair production in high-intensity laser-plasma interactions  

E-Print Network [OSTI]

Gamma-ray and electron-positron pair production will figure prominently in laser-plasma experiments with next generation lasers. Using a Monte Carlo approach we show that straggling effects arising from the finite recoil an electron experiences when it emits a high energy photon, increase the number of pairs produced on further interaction with the laser fields.

Roland Duclous; John Kirk; Anthony Bell

2010-10-21T23:59:59.000Z

264

High-resolution sedimentary record of the last deglaciation from a high-altitude lake in Ethiopia  

E-Print Network [OSTI]

High-resolution sedimentary record of the last deglaciation from a high-altitude lake in Ethiopia J Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia d CEREGE, Europôle de l'Arbois, B.P. 80, 13545 long core collected from Lake Garba Guracha (Ethiopia) associated with a precise AMS-14 C time

Brest, Université de

265

High-resolution 18F-FDG PET with MRI for monitoring response to treatment in rheumatoid arthritis  

E-Print Network [OSTI]

of a dedicated breast PET/CT scanner during human imaging. Jhigh-resolution 18 F-FDG PET images (pseudocolor) overlaidMONTH High-resolution 18 F-FDG PET with MRI for monitoring

2010-01-01T23:59:59.000Z

266

Hadronic energy resolution of a highly granular scintillator-steel hadron calorimeter using software compensation techniques  

E-Print Network [OSTI]

The energy resolution of a highly granular 1 m3 analogue scintillator-steel hadronic calorimeter is studied using charged pions with energies from 10 GeV to 80 GeV at the CERN SPS. The energy resolution for single hadrons is determined to be approximately 58%/sqrt(E/GeV}. This resolution is improved to approximately 45%/sqrt(E/GeV) with software compensation techniques. These techniques take advantage of the event-by-event information about the substructure of hadronic showers which is provided by the imaging capabilities of the calorimeter. The energy reconstruction is improved either with corrections based on the local energy density or by applying a single correction factor to the event energy sum derived from a global measure of the shower energy density. The application of the compensation algorithms to Geant4 simulations yield resolution improvements comparable to those observed for real data.

CALICE Collaboration; C. Adloff; J. Blaha; J. -J. Blaising; C. Drancourt; A. Espargilière; R. Gaglione; N. Geffroy; Y. Karyotakis; J. Prast; G. Vouters; K. Francis; J. Repond; J. Smith; L. Xia; E. Baldolemar; J. Li; S. T. Park; M. Sosebee; A. P. White; J. Yu; T. Buanes; G. Eigen; Y. Mikami; N. K. Watson; T. Goto; G. Mavromanolakis; M. A. Thomson; D. R. Ward; W. Yan; D. Benchekroun; A. Hoummada; Y. Khoulaki; M. Benyamna; C. Cârloganu; F. Fehr; P. Gay; S. Manen; L. Royer; G. C. Blazey; A. Dyshkant; J. G. R. Lima; V. Zutshi; J. -Y. Hostachy; L. Morin; U. Cornett; D. David; G. Falley; K. Gadow; P. Göttlicher; C. Günter; B. Hermberg; S. Karstensen; F. Krivan; A. -I. Lucaci-Timoce; S. Lu; B. Lutz; S. Morozov; V. Morgunov; M. Reinecke; F. Sefkow; P. Smirnov; M. Terwort; A. Vargas-Trevino; N. Feege; E. Garutti; I. Marchesini; M. Ramilli; P. Eckert; T. Harion; A. Kaplan; H. -Ch. Schultz-Coulon; W. Shen; R. Stamen; A. Tadday; B. Bilki; E. Norbeck; Y. Onel; G. W. Wilson; K. Kawagoe; P. D. Dauncey; A. -M. Magnan; M. Wing; F. Salvatore; E. Calvo Alamillo; M. -C. Fouz; J. Puerta-Pelayo; V. Balagura; B. Bobchenko; M. Chadeeva; M. Danilov; A. Epifantsev; O. Markin; R. Mizuk; E. Novikov; V. Rusinov; E. Tarkovsky; N. Kirikova; V. Kozlov; P. Smirnov; Y. Soloviev; P. Buzhan; B. Dolgoshein; A. Ilyin; V. Kantserov; V. Kaplin; A. Karakash; E. Popova; S. Smirnov; C. Kiesling; S. Pfau; K. Seidel; F. Simon; C. Soldner; M. Szalay; M. Tesar; L. Weuste; J. Bonis; B. Bouquet; S. Callier; P. Cornebise; Ph. Doublet; F. Dulucq; M. Faucci Giannelli; J. Fleury; H. Li; G. Martin-Chassard; F. Richard; Ch. de la Taille; R. Pöschl; L. Raux; N. Seguin-Moreau; F. Wicek; M. Anduze; V. Boudry; J-C. Brient; D. Jeans; P. Mora de Freitas; G. Musat; M. Reinhard; M. Ruan; H. Videau; B. Bulanek; J. Zacek; J. Cvach; P. Gallus; M. Havranek; M. Janata; J. Kvasnicka; D. Lednicky; M. Marcisovsky; I. Polak; J. Popule; L. Tomasek; M. Tomasek; P. Ruzicka; P. Sicho; J. Smolik; V. Vrba; J. Zalesak; B. Belhorma; H. Ghazlane; T. Takeshita; S. Uozumi; J. Sauer; S. Weber; C. Zeitnitz

2012-09-27T23:59:59.000Z

267

X-ray Observations of Galaxies: The Importance of Deep High-Resolution Observations  

E-Print Network [OSTI]

X-ray observations of galaxies have grown from a curiosity into a full-fledged field of astronomy. These observations provide unique information on black holes, binary stars, and the hot phase of the ISM, which can be used to constrain the chemical evolution of the Universe, and the joint evolution of galaxies and massive black holes. These exciting results are due in large part to the high-resolution capability of {\\it Chandra}. To follow on {\\it Chandra} and push forward this science past the present capabilities, our community must build a high-resolution (sub-arcsecond) large-area (several square meters) X-ray telescope.

G. Fabbiano

2007-11-30T23:59:59.000Z

268

Method and apparatus for delivering high power laser energy over long distances  

DOE Patents [OSTI]

Systems, devices and methods for the transmission of 1 kW or more of laser energy deep into the earth and for the suppression of associated nonlinear phenomena. Systems, devices and methods for the laser drilling of a borehole in the earth. These systems can deliver high power laser energy down a deep borehole, while maintaining the high power to advance such boreholes deep into the earth and at highly efficient advancement rates.

Zediker, Mark S; Rinzler, Charles C; Faircloth, Brian O; Koblick, Yeshaya; Moxley, Joel F

2013-08-20T23:59:59.000Z

269

Method and system for advancement of a borehole using a high power laser  

DOE Patents [OSTI]

There is provided a system, apparatus and methods for the laser drilling of a borehole in the earth. There is further provided with in the systems a means for delivering high power laser energy down a deep borehole, while maintaining the high power to advance such boreholes deep into the earth and at highly efficient advancement rates, a laser bottom hole assembly, and fluid directing techniques and assemblies for removing the displaced material from the borehole.

Moxley, Joel F.; Land, Mark S.; Rinzler, Charles C.; Faircloth, Brian O.; Zediker, Mark S.

2014-09-09T23:59:59.000Z

270

The Potential for Bayesian Compressive Sensing to Significantly Reduce Electron Dose in High Resolution STEM Images  

SciTech Connect (OSTI)

The use of high resolution imaging methods in the scanning transmission electron microscope (STEM) is limited in many cases by the sensitivity of the sample to the beam and the onset of electron beam damage (for example in the study of organic systems, in tomography and during in-situ experiments). To demonstrate that alternative strategies for image acquisition can help alleviate this beam damage issue, here we apply compressive sensing via Bayesian dictionary learning to high resolution STEM images. These experiments successively reduce the number of pixels in the image (thereby reducing the overall dose while maintaining the high resolution information) and show promising results for reconstructing images from this reduced set of randomly collected measurements. We show that this approach is valid for both atomic resolution images and nanometer resolution studies, such as those that might be used in tomography datasets, by applying the method to images of strontium titanate and zeolites. As STEM images are acquired pixel by pixel while the beam is scanned over the surface of the sample, these post acquisition manipulations of the images can, in principle, be directly implemented as a low-dose acquisition method with no change in the electron optics or alignment of the microscope itself.

Stevens, Andrew J.; Yang, Hao; Carin, Lawrence; Arslan, Ilke; Browning, Nigel D.

2014-02-11T23:59:59.000Z

271

Pulsed laser kinetic studies of liquids under high pressure  

SciTech Connect (OSTI)

Experiments have been developed for measuring the rates of chemical reactions liquids and in supercritical Co[sub 2]. A pulsed (Q-switch) Nd:YAG laser at 355 nm was the pump beam for laser flash photolysis studies of molybdenum and tungsten hexacarbonyls undergoing ligand displacement reactions by bidentate chelating agents such as 2,2[prime]-bipyridine in toluene. Experiments were carried out at 0.1 to 150 MPa. In the case of molybdenum complexes, the reaction mechanism for thermal ring closure is found from activation volumes to change from associative interchange to dissociative interchange as substituents on the 2,2[prime]-bipyridine ligands become bulkier. In a similar study of more rigid, substituted phenanthroline bidentate ligands it was found that substituent bulkiness had little effect on the thermal ring closure mechanism. Similar high pressure flash photolysis experiments with tungsten hexacarbonyl have also been completed. The concentration dependence of the fluorescence and nonradiative decay quantum yields for cresyl violet in several solvent have been reported as well as stability constants for the complexation of lithium ion by four different crown ethers dissolved in a room temperature molten salt.

Eyring, E.M.

1993-06-21T23:59:59.000Z

272

A High Resolution, Light-Weight, Synthetic Aperture Radar for UAV Application  

SciTech Connect (OSTI)

(U) Sandia National Laboratories in collaboration with General Atomics (GA) has designed and built a high resolution, light-weight, Ku-band Synthetic Aperture Radar (SAR) known as "Lynx". Although Lynx can be operated on a wide variety of manned and unmanned platforms, its design is optimized for use on medium altitude Unmanned Aerial Vehicles (UAVS). In particular, it can be operated on the Predator, I-GNAT, and Prowler II platforms manufactured by GA. (U) The radar production weight is less than 120 lb and operates within a 3 GHz band from 15.2 GHz to 18.2 GHz with a peak output power of 320 W. Operating range is resolution and mode dependent but can exceed 45 km in adverse weather (4 mm/hr rain). Lynx has operator selectable resolution and is capable of 0.1 m resolution in spotlight mode and 0.3 m resolution in stripmap mode, over substantial depression angles (5 to 60 deg) and squint angles (broadside ±45 deg). Real-time Motion Compensation is implemented to allow high-quality image formation even during vehicle turns and other maneuvers.

Doerry, A.W.; Hensley, W.H.; Stence, J.; Tsunoda, S.I. Pace, F.; Walker, B,C.; Woodring, M.

1999-05-27T23:59:59.000Z

273

CO (3 – 2) HIGH-RESOLUTION SURVEY OF THE GALACTIC PLANE: R1  

SciTech Connect (OSTI)

We present the first release (R1) of data from the CO High-Resolution Survey (COHRS), which maps a strip of the inner Galactic plane in {sup 12}CO (J = 3 ? 2). The data are taken using the Heterodyne Array Receiver Programme on the James Clerk Maxwell Telescope (JCMT) in Hawaii, which has a 14 arcsec angular resolution at this frequency. When complete, this survey will cover |b| ? 0.°5 between 10° < l < 65°. This first release covers |b| ? 0.°5 between 10.°25 < l < 17.°5 and 50.°25 < l < 55.°25, and |b| ? 0.°25 between 17.°5 < l < 50.°25. The data are smoothed to a velocity resolution of 1 km s{sup –1}, a spatial resolution of 16 arcsec and achieve a mean rms of ?1 K. COHRS data are available to the community online at http://dx.doi.org/10.11570/13.0002. In this paper we describe the data acquisition and reduction techniques used and present integrated intensity images and longitude-velocity maps. We also discuss the noise characteristics of the data. The high resolution is a powerful tool for morphological studies of bubbles and filaments while the velocity information shows the spiral arms and outflows. These data are intended to complement both existing and upcoming surveys, e.g., the Bolocam Galactic Plane Survey (BGPS), ATLASGAL, the Herschel Galactic Plane Survey (Hi-GAL) and the JCMT Galactic Plane Survey with SCUBA-2 (JPS)

Dempsey, J. T.; Thomas, H. S.; Currie, M. J., E-mail: j.dempsey@jach.hawaii.edu, E-mail: h.thomas@jach.hawaii.edu, E-mail: m.currie@jach.hawaii.edu [Joint Astronomy Centre, 660 N. Aohoku Place, Hilo, HI 96720 (United States)

2013-11-01T23:59:59.000Z

274

Combining Laser Ablation/Liquid Phase Collection Surface Sampling and High-Performance Liquid Chromatography Electrospray Ionization Mass Spectrometry  

SciTech Connect (OSTI)

This paper describes the coupling of ambient pressure transmission geometry laser ablation with a liquid phase sample collection method for surface sampling and ionization with subsequent mass spectral analysis. A commercially available autosampler was adapted to produce a liquid droplet at the end of the syringe injection needle while in close proximity to the surface to collect the sample plume produced by laser ablation. The sample collection was followed by either flow injection or a high performance liquid chromatography (HPLC) separation of the extracted components and detection with electrospray ionization mass spectrometry (ESI-MS). To illustrate the analytical utility of this coupling, thin films of a commercial ink sample containing rhodamine 6G and of mixed isobaric rhodamine B and 6G dyes on glass microscope slides were analyzed. The flow injection and HPLC/ESI-MS analysis revealed successful laser ablation, capture and, with HPLC, the separation of the two compounds. The ablated circular area was about 70 m in diameter for these experiments. The spatial sampling resolution afforded by the laser ablation, as well as the ability to use sample processing methods like HPLC between the sample collection and ionization steps, makes this combined surface sampling/ionization technique a highly versatile analytical tool.

Ovchinnikova, Olga S [ORNL; Kertesz, Vilmos [ORNL; Van Berkel, Gary J [ORNL

2011-01-01T23:59:59.000Z

275

High-Resolution 3 T MR Microscopy Imaging of Arterial Walls  

SciTech Connect (OSTI)

Purpose. To achieve a high spatial resolution in MR imaging that allows for clear visualization of anatomy and even histology and documentation of plaque morphology in in vitro samples from patients with advanced atherosclerosis. A further objective of our study was to evaluate whether T2-weighted high-resolution MR imaging can provide accurate classification of atherosclerotic plaque according to a modified American Heart Association classification. Methods. T2-weighted images of arteries were obtained in 13 in vitro specimens using a 3 T MR unit (Medspec 300 Avance/Bruker, Ettlingen, Germany) combined with a dedicated MR microscopy system. Measurement parameters were: T2-weighted sequences with TR 3.5 sec, TE 15-120 msec; field of view (FOV) 1.4 x 1.4; NEX 8; matrix 192; and slice thickness 600 {mu}m. MR measurements were compared with corresponding histologic sections. Results. We achieved excellent spatial and contrast resolution in all specimens. We found high agreement between MR images and histology with regard to the morphology and extent of intimal proliferations in all but 2 specimens. We could differentiate fibrous caps and calcifications from lipid plaque components based on differences in signal intensity in order to differentiate hard and soft atheromatous plaques. Hard plaques with predominantly intimal calcifications were found in 7 specimens, and soft plaques with a cholesterol/lipid content in 5 cases. In all specimens, hemorrhage or thrombus formation, and fibrotic and hyalinized tissue could be detected on both MR imaging and histopathology. Conclusion. High-resolution, high-field MR imaging of arterial walls demonstrates the morphologic features, volume, and extent of intimal proliferations with high spatial and contrast resolution in in vitro specimens and can differentiate hard and soft plaques.

Sailer, Johannes, E-mail: johannes.sailer@univie.ac.at; Rand, Thomas [University of Vienna, Department of Angiography and Interventional Radiology (Austria); Berg, Andreas [University of Vienna, Institute for Medical Physics (Austria); Sulzbacher, Irene [University of Vienna, Clinical Institute of Pathology (Austria); Peloschek, P. [University of Vienna, Department of Angiography and Interventional Radiology (Austria); Hoelzenbein, Thomas [University of Vienna, Department of Surgery (Austria); Lammer, Johannes [University of Vienna, Department of Angiography and Interventional Radiology (Austria)

2006-10-15T23:59:59.000Z

276

Final Report: High Spectral Resolution Atmospheric Emitted Radiance Studies with the ARM UAV  

SciTech Connect (OSTI)

The active participation in the Atmospheric Radiation Measurement (ARM) Unmanned Airborne Vehicle (UAV) science team that was anticipated in the grant proposal was indefinitely delayed after the first year due to a programmatic decision to exclude the high spectral resolution observations from the existing ARM UAV program. However, this report shows that substantial progress toward the science objectives of this grant have made with the help of separate funding from NASA and other agencies. In the four year grant period (including time extensions), a new high spectral resolution instrument has been flown and has successfully demonstrated the ability to obtain measurements of the type needed in the conduct of this grant. In the near term, the third water vapor intensive observing period (WVIOP-3) in October 2000 will provide an opportunity to bring the high spectral resolution observations of upwelling radiance into the ARM program to complement the downwelling radiance observations from the existing ARM AERI instruments. We look forward to a time when the ARM-UAV program is able to extend its scope to include the capability for making these high spectral resolution measurements from a UAV platform.

Revercomb, Henry E.

1999-12-31T23:59:59.000Z

277

Detection of Heavy Metal Ions in Water by High-Resolution Surface Plasmon Resonance  

E-Print Network [OSTI]

Detection of Heavy Metal Ions in Water by High-Resolution Surface Plasmon Resonance Spectroscopy voltammetry (ASV) capability has been demonstrated for detecting heavy metal ions in water. Metal ions in water from part-per-million to sub-part-per-billion levels with good linearity. Heavy metal poisoning

Zhang, Yanchao

278

Net accumulation of the Greenland ice sheet: High resolution modeling of climate changes  

E-Print Network [OSTI]

: Kiilsholm, S., J. H. Christensen, K. Dethloff, and A. Rinke, Net accumulation of the Greenland ice sheetNet accumulation of the Greenland ice sheet: High resolution modeling of climate changes Sissi, Denmark Klaus Dethloff and Annette Rinke Alfred Wegener Institute for Polar and Marine Research

Born, Andreas

279

Spatially-varying SAR models and Bayesian Inference for High-Resolution Lattice Data  

E-Print Network [OSTI]

Spatially-varying SAR models and Bayesian Inference for High-Resolution Lattice Data Chiranjit Inverse problems Lattice data Non-stationary random fields Satellite imagery data Sparse spatial model- lenge our modelling and computational abilities as data volumes increase. Similarly, as spatial scales

West, Mike

280

High-resolution forest carbon stocks and emissions in Gregory P. Asnera,1  

E-Print Network [OSTI]

carbon emissions by 47% over deforestation alone, and secondary regrowth provided an 18% offset againstHigh-resolution forest carbon stocks and emissions in the Amazon Gregory P. Asnera,1 , George V. N Deforestation and Degradation (REDD) depend on mapping and monitoring of tropical forest carbon stocks

Saleska, Scott

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

HIGH SPATIAL RESOLUTION SOLAR ATLAS IN PROVENCE-ALPES-CTE D'AZUR  

E-Print Network [OSTI]

the advantages of both the satellite-based solar radiation databases and the in situ ground station measurementsHIGH SPATIAL RESOLUTION SOLAR ATLAS IN PROVENCE-ALPES-CÃ?TE D'AZUR Philippe Blanc 1 , Bella EspinarTech / ARMINES, Centre for Energy and Processes, Sophia Antipolis (France) 2 TRANSVALOR, Sophia Antipolis (France

Paris-Sud XI, Université de

282

OVERVIEW OF SELECTED SURROGATE TECHNOLOGIES FOR HIGH-TEMPORAL RESOLUTION SUSPENDED-SEDIMENT MONITORING  

E-Print Network [OSTI]

OVERVIEW OF SELECTED SURROGATE TECHNOLOGIES FOR HIGH- TEMPORAL RESOLUTION SUSPENDED-SEDIMENT for characterizing selected properties of suspended sediments in rivers are being augmented and in some cases of quantifiably accurate data for use primarily in sediment-flux computations. Turbidity is the most common

283

High spatial resolution subsurface thermal emission microscopy S. B. Ippolito,a)  

E-Print Network [OSTI]

a total optical power proportional to its absolute temperature to the fourth power. An object that hasHigh spatial resolution subsurface thermal emission microscopy S. B. Ippolito,a) S. A. Thorne, M. G increasing lens technique to subsurface thermal emission microscopy of Si integrated circuits. We achieve

284

High spatial resolution X-ray and gamma ray imaging system using diffraction crystals  

DOE Patents [OSTI]

A method and a device for high spatial resolution imaging of a plurality of sources of x-ray and gamma-ray radiation are provided. The device comprises a plurality of arrays, with each array comprising a plurality of elements comprising a first collimator, a diffracting crystal, a second collimator, and a detector.

Smither, Robert K. (Hinsdale, IL)

2011-05-17T23:59:59.000Z

285

High resolution spectroscopic characterization of the FGK stars in the Solar neighbourhood  

E-Print Network [OSTI]

the EW #12;FIGURE 1. Left panel: EW Li I vs. (B-V). Different colors and symbols are used for stars). The obtained values are plotted in the EW(Li I) vs. spectral type diagram in Fig. 1 (left panel). ComparingHigh resolution spectroscopic characterization of the FGK stars in the Solar neighbourhood R. M

Complutense de Madrid, Universidad

286

Virtually distortion-free imaging system for large field, high resolution lithography  

DOE Patents [OSTI]

Virtually distortion free large field high resolution imaging is performed using an imaging system which contains large field distortion or field curvature. A reticle is imaged in one direction through the optical system to form an encoded mask. The encoded mask is then imaged back through the imaging system onto a wafer positioned at the reticle position.

Hawryluk, A.M.; Ceglio, N.M.

1993-01-05T23:59:59.000Z

287

ATLAS-BASED FIBER CLUSTERING FOR MULTI-SUBJECT ANALYSIS OF HIGH ANGULAR RESOLUTION DIFFUSION  

E-Print Network [OSTI]

ATLAS-BASED FIBER CLUSTERING FOR MULTI-SUBJECT ANALYSIS OF HIGH ANGULAR RESOLUTION DIFFUSION and a co-registered probabilistic DTI atlas to select key pathways, applied a threshold and median anatomy 3. Make tract analysis robust to differences in the atlas and subject 1. Image Data · 105-gradient

Thompson, Paul

288

HIGH RESOLUTION MOTION ESTIMATION OF SEA ICE USING AN IMPLICIT QUAD-TREE APPROACH  

E-Print Network [OSTI]

and dynamic nature of sea ice is intimately connected with the thermal regulation of planetary heat transferHIGH RESOLUTION MOTION ESTIMATION OF SEA ICE USING AN IMPLICIT QUAD-TREE APPROACH M. Thomas, C. A data products. Since the motion is extracted from the image data iteratively, the estimated field

Geiger, Cathleen

289

Abrupt climate changes for Iceland during the last millennium: evidence from high resolution sea ice reconstructions  

E-Print Network [OSTI]

constructed using a novel proxy based on the presence in sediments of a biomarker (IP25) produced by sea ice produced by sea ice algae (Figure 2), to obtain an uninterrupted, high resolution (ca. 2-5 yr) record ice reconstructions Guillaume Massé1 , Steven J. Rowland1 , Marie-Alexandrine Sicre2 , Jeremy Jacob3

Paris-Sud XI, Université de

290

HighResolution Numerical Methods for MicellarPolymer Flooding and Surfactant Enhanced Aquifer Remediation  

E-Print Network [OSTI]

been used to study the micellar­ polymer flooding process in enhanced oil recovery [12], [18], [19 in practical im­ plementation of enhanced oil recovery techniques at this time, there is increasing interestHigh­Resolution Numerical Methods for Micellar­Polymer Flooding and Surfactant Enhanced Aquifer

Trangenstein, John A.

291

CeBr3 as a High-Resolution Gamma-Ray Detector  

SciTech Connect (OSTI)

Lanthanum halide (LaBr3:Ce) scintillators have been well-documented as high-resolution gamma-ray detectors that are operated at room temperature. These scintillators have better resolution (<3% at 662 keV) relative to sodium iodide (NaI(Tl)) scintillators (7% at 662 keV), but the naturally occurring radioactive isotope 138La causes self-activity in the crystal that occludes portions of the gamma-ray spectrum. This selfactivity limits the use of LaBr3:Ce in high-sensitivity applications. Cerium, the dopant in the LaBr3:Ce matrix possesses useful scintillation properties, and its selfactivity is on the order of 3750 times less than La; however, Ce has not been fully characterized as the chief component in a scintillation detector. This work investigated Ce as the key scintillation matrix component in a scintillation detector with the hypothesis that CeBr3 promises energy resolution comparable or superior to LaBr3:Ce. The researchers involved with this work believe that CeBr3 may be the answer to obtaining high-temperature, high-resolution spectra with greater sensitivity than LaBr3:Ce.

Michael Reed, Paul Guss, Christopher Contreras

2008-11-13T23:59:59.000Z

292

Energy Resolved High Resolution Dynamic E-Cell Materials Research. Final Report  

SciTech Connect (OSTI)

The purpose of this project was to develop in situ materials reaction observation capability in an intermediate voltage high resolution transmission electron microscope. To accomplish this we purchased a GATAN imaging energy filter system, a hot stage, and designed and constructed an environmental cell and real time television image recording system, and installed this equipment on our EM 430 intermediate voltage electron microscope.

Carpenter, Ray; Sharma, Renu; Mayer, James

2000-05-16T23:59:59.000Z

293

HIGH-RESOLUTION MID-INFRARED SPECTROSCOPY OF ULTRALUMINOUS INFRARED GALAXIES D. Farrah,1  

E-Print Network [OSTI]

infrared emission. This initially provoked heated debate between a ``starburst'' camp and an ``activeHIGH-RESOLUTION MID-INFRARED SPECTROSCOPY OF ULTRALUMINOUS INFRARED GALAXIES D. Farrah,1 J. Bernard, 10Y37 m spectra of 53 ultraluminous infrared galaxies (ULIRGs), taken using the Infrared Spectrograph

Galis, Frietson

294

High Resolution Sharp Computational Methods for Elliptic and Parabolic Problems in Complex Geometries  

E-Print Network [OSTI]

High Resolution Sharp Computational Methods for Elliptic and Parabolic Problems in Complex Geometries Frédéric Gibou Chohong Min Ron Fedkiw November 2, 2012 In honor of Stan Osher's 70th birthday of chemical species (see [48] and the references therein); they are also core building blocks in fields

Fedkiw, Ron

295

Scene Reconstruction from High Spatio-Angular Resolution Light Fields Changil Kim1,2  

E-Print Network [OSTI]

Scene Reconstruction from High Spatio-Angular Resolution Light Fields Changil Kim1,2 Henning Zimmer Figure 1: Our method reconstructs accurate depth from light fields of complex scenes. The images on the left show a 2D slice of a 3D input light field, a so called epipolar-plane image (EPI), and two out

Zimmer, Henning

296

Noninvasive high-resolution detection of the arterial and venous input function through a PET Wrist  

E-Print Network [OSTI]

Noninvasive high-resolution detection of the arterial and venous input function through a PET Wrist using planar coincidence images. I. INTRODUCTION Quantitative Positron Emission Tomography (PET) often determine the input function. These techniques include external monitors and PET scanners that measure

297

Compact, High-Resolution, Multi-Layer Semiconductor PET Detector Module  

E-Print Network [OSTI]

Compact, High-Resolution, Multi-Layer Semiconductor PET Detector Module Summary Multi tomography (PET) systems, but the conventional electrodes used require a prohibitive number of readout channels. Now, a breakthrough compact PET detector offers a specialized configuration of cross strip

Ohta, Shigemi

298

CLASSIFICATION OF BIOMEDICAL HIGH-RESOLUTION MICRO-CT IMAGES FOR DIRECT VOLUME RENDERING  

E-Print Network [OSTI]

CLASSIFICATION OF BIOMEDICAL HIGH-RESOLUTION MICRO-CT IMAGES FOR DIRECT VOLUME RENDERING Maite L,cerquide,davidm,anna}@maia.ub.es ABSTRACT This paper introduces a machine learning approach into the process of direct volume rendering that generates the classification func- tion within the optical property function used for rendering. Briefly

López-Sánchez, Maite

299

High resolution RCM simulation of eastern Mediterranean climate and its expected changes to 2050  

E-Print Network [OSTI]

High resolution RCM simulation of eastern Mediterranean climate and its expected changes to 2050. Modern global climate change evaluations usually based on application of coupled atmosphere-ocean global by the Intergovernmental Panel on Climate Change (IPCC). A number of different anthropogenic emission scenarios have been

Adler, Joan

300

High-resolution population grids and future scenarios for Tanzania Philip J. Platts & Ruth D. Swetnam  

E-Print Network [OSTI]

this grid and the LandScan grid to remove all persons from these protected areas (Single Map Algebra Tool1 High-resolution population grids and future scenarios for Tanzania Philip J. Platts & Ruth D, were obtained by hindcasting the LandScan grid on a ward-by-ward basis, such that ward totals matched

Marchant, Rob

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

A high-resolution mapped grid algorithm for compressible multiphase flow problems  

E-Print Network [OSTI]

A high-resolution mapped grid algorithm for compressible multiphase flow problems K.-M. Shyue 18 August 2010 Keywords: Compressible multiphase flow Fluid-mixture model Mapped grids Wave-propagation method Stiffened gas equation of state a b s t r a c t We describe a simple mapped-grid approach

Shyue, Keh-Ming

302

A High Resolution Intergalactic Explorer for the Soft X-ray/FUV  

E-Print Network [OSTI]

We present a mission concept for high resolution X-ray spectroscopy with a resolving power, R~6000, (c.f. R=Web'. The Cosmic Web is predicted to contain most of the normal matter (baryons) in the nearby Universe.

Martin Elvis; Fabrizio Fiore; the CWE Team

2003-03-19T23:59:59.000Z

303

ADVANCES IN ELECTRONICS AND ELECTRON PHYSICS, VOL. 83 LVSEM for High Resolution Topographic and Density  

E-Print Network [OSTI]

ADVANCES IN ELECTRONICS AND ELECTRON PHYSICS, VOL. 83 LVSEM for High Resolution Topographic Surface-Imaging Scanning Electron Microscope 205 C. Electrons as Probes in Scanning Microscopes 205 D. Limitations Associated with the Use of Electrons as the Probing Radiation 206 E. Response to These Limitations

Pawley, James

304

Increasing the Scalability of PISM for High Resolution Ice Sheet Models Phillip Dickens  

E-Print Network [OSTI]

Increasing the Scalability of PISM for High Resolution Ice Sheet Models Phillip Dickens School at large. One important piece of the climate puzzle is how the dynamics of large-scale ice sheets developed several simulation models to predict and understand the behavior of large-scale ice sheets

Dickens, Phillip M.

305

Gain media edge treatment to suppress amplified spontaneous emission in a high power laser  

DOE Patents [OSTI]

A novel method and apparatus for suppressing ASE and parasitic oscillation modes in a high average power laser is introduced. By roughening one or more peripheral edges of a solid-state crystal or ceramic laser gain media and by bonding such edges using a substantially high index bonding elastomer or epoxy to a predetermined electromagnetic absorbing arranged adjacent to the entire outer surface of the peripheral edges of the roughened laser gain media, ASE and parasitic oscillation modes can be effectively suppressed.

Hackel, Lloyd A. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Fochs, Scott N. (Livermore, CA); Rotter, Mark D. (San Ramon, CA); Letts, Stephan A. (San Ramon, CA)

2008-12-09T23:59:59.000Z

306

Methods for enhancing the efficiency of creating a borehole using high power laser systems  

DOE Patents [OSTI]

Methods for utilizing 10 kW or more laser energy transmitted deep into the earth with the suppression of associated nonlinear phenomena to enhance the formation of Boreholes. Methods for the laser operations to reduce the critical path for forming a borehole in the earth. These methods can deliver high power laser energy down a deep borehole, while maintaining the high power to perform operations in such boreholes deep within the earth.

Zediker, Mark S.; Rinzler, Charles C.; Faircloth, Brian O.; Koblick, Yeshaya; Moxley, Joel F.

2014-06-24T23:59:59.000Z

307

Gas Dynamics in the Barred Seyfert Galaxy NGC4151 - II. High Resolution HI Study  

E-Print Network [OSTI]

We present sensitive, high angular resolution (6" x 5") 21-cm observations of the neutral hydrogen in the nearby barred Seyfert galaxy, NGC4151. These HI observations, obtained using the VLA in B-configuration, are the highest resolution to date of this galaxy, and reveal hitherto unprecedented detail in the distribution and kinematics of the HI on sub-kiloparsec scales. A complete analysis and discussion of the HI data are presented and the global properties of the galaxy are related to the bar dynamics presented in Paper I.

C. G. Mundell; A. Pedlar; D. L. Shone; A. Robinson

1998-12-09T23:59:59.000Z

308

High-resolution chemical imaging of gold nanoparticles using hard x-ray ptychography  

SciTech Connect (OSTI)

We combine resonant scattering with (ptychographic) scanning coherent diffraction microscopy to determine the chemical state of gold nanoparticles with high spatial resolution. Ptychographic images of the sample are recorded for a series of energies around the gold L{sub 3} absorption edge. From these data, chemical information in the form of absorption and resonant scattering spectra is reconstructed at each location in the sample. For gold nanoparticles of about 100 nm diameter, a spatial resolution of about 20-30 nm is obtained. In the future, this microscopy approach will open the way to operando studies of heterogeneous catalysts on the nanometer scale.

Hoppe, R.; Patommel, J.; Schroer, C. G. [Institute of Structural Physics, Technische Universitaet Dresden, D-01062 Dresden (Germany)] [Institute of Structural Physics, Technische Universitaet Dresden, D-01062 Dresden (Germany); Reinhardt, J. [Institute of Structural Physics, Technische Universitaet Dresden, D-01062 Dresden (Germany) [Institute of Structural Physics, Technische Universitaet Dresden, D-01062 Dresden (Germany); Deutsches Elektronen-Synchrotron DESY, D-22607 Hamburg (Germany)] [Germany; Hofmann, G.; Grunwaldt, J.-D. [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, D-76131 Karlsruhe (Germany)] [Institute for Chemical Technology and Polymer Chemistry, Karlsruhe Institute of Technology, D-76131 Karlsruhe (Germany); Damsgaard, C. D. [Center for Electron Nanoscopy and Department of Physics, Technical University of Denmark, DK-2800 Lyngby (Denmark)] [Center for Electron Nanoscopy and Department of Physics, Technical University of Denmark, DK-2800 Lyngby (Denmark); Wellenreuther, G.; Falkenberg, G. [Deutsches Elektronen-Synchrotron DESY, D-22607 Hamburg (Germany)] [Deutsches Elektronen-Synchrotron DESY, D-22607 Hamburg (Germany)

2013-05-20T23:59:59.000Z

309

High Resolution BPM Upgrade for the ATF Damping Ring at KEK  

E-Print Network [OSTI]

A beam position monitor (BPM) upgrade at the KEK Accelerator Test Facility (ATF) damping ring has been accomplished, carried out by a KEK/FNAL/SLAC collaboration under the umbrella of the global ILC R&D effort. The upgrade consists of a high resolution, high reproducibility read-out system, based on analog and processing, and also implements a new automatic gain error correction schema. The technical concept and realization as well as results of beam studies are presented.

Eddy, N; Fellenz, B; Gianfelice-Wendt, E; Prieto, P; Rechenmacher, R; Semenov, A; Voy, D; Wendt, M; Zhang, D; Terunuma, N; Urakawa, J

2012-01-01T23:59:59.000Z

310

High resolution neutron crystallographic studies of the hydration of coenzyme cob(II)alamin  

SciTech Connect (OSTI)

The hydration of coenzyme cob(II)alamin has been studied using high resolution monochromatic neutron crystallographic data collected at room temperature to a resolution of surrounded by flexible side chains with terminal functional groups may be significant for 0.92 on the original diffractometer D19 with a prototype 4o x 64o detector at the high-flux reactor neutron source run by the Institute Laue Langevin. The resulting structure provides H bonding parameters for the hydration of biomacromolecules to unprecedented accuracy. These experimental parameters will be used to define more accurate force-fields for biomacromolecular structure refinement. The presence of a hydrophobic bowl motif efficient scavenging of ligands. The feasibility of extending the resolution of this structure to ultra high resolution was investigated by collecting time-of-flight neutron crystallographic data on diffractometer TOPAZ with a prototype array of 14 modular 21o x 21o detectors at the Spallation Neutron Source run by Oak Ridge National Laboratory.

Jogl, Gerwald [Brown University; Wang, Xiaoping [ORNL; Mason, Sax [Institut Laue-Langevin (ILL); Kovalevsky, Andrey [Los Alamos National Laboratory (LANL); Mustyakimov, Marat [Los Alamos National Laboratory (LANL); Fisher, Zoe [Los Alamos National Laboratory (LANL); Hoffmann, Christina [ORNL; Kratky, Christoph [Institute of Biosciences, University of Graz; Langan, Paul [ORNL

2011-01-01T23:59:59.000Z

311

High spatial resolution upgrade of the electron cyclotron emission radiometer for the DIII-D tokamak  

SciTech Connect (OSTI)

The 40-channel DIII-D electron cyclotron emission (ECE) radiometer provides measurements of T{sub e}(r,t) at the tokamak midplane from optically thick, second harmonic X-mode emission over a frequency range of 83–130 GHz. The frequency spacing of the radiometer's channels results in a spatial resolution of ?1–3 cm, depending on local magnetic field and electron temperature. A new high resolution subsystem has been added to the DIII-D ECE radiometer to make sub-centimeter (0.6–0.8 cm) resolution T{sub e} measurements. The high resolution subsystem branches off from the regular channels’ IF bands and consists of a microwave switch to toggle between IF bands, a switched filter bank for frequency selectivity, an adjustable local oscillator and mixer for further frequency down-conversion, and a set of eight microwave filters in the 2–4 GHz range. Higher spatial resolution is achieved through the use of a narrower (200 MHz) filter bandwidth and closer spacing between the filters’ center frequencies (250 MHz). This configuration allows for full coverage of the 83–130 GHz frequency range in 2 GHz bands. Depending on the local magnetic field, this translates into a “zoomed-in” analysis of a ?2–4 cm radial region. Expected uses of these channels include mapping the spatial dependence of Alfven eigenmodes, geodesic acoustic modes, and externally applied magnetic perturbations. Initial T{sub e} measurements, which demonstrate that the desired resolution is achieved, are presented.

Truong, D. D., E-mail: dtruong@wisc.edu [Department of Engineering Physics, University of Wisconsin-Madison, Madison, Wisconsin 53706 (United States); Austin, M. E. [Institute for Fusion Studies, University of Texas, Austin, Texas, 78712 (United States)

2014-11-15T23:59:59.000Z

312

Overview of High Energy Lasers: Past, Present, and Future? D. L. Carroll1  

E-Print Network [OSTI]

at high energy laser systems and their effects, respectively. Einstein published the concept of stimulated for a problem" and this needed to be addressed. Weapon-type "ray guns" were commonly envisioned (and liberally) to be a daunting challenge, especially so for handheld weapon systems. Still, several impressive high energy laser

Carroll, David L.

313

High-throughput metal nanoparticle catalysis by pulsed laser ablation Selim Senkan a,*, Michael Kahn a  

E-Print Network [OSTI]

High-throughput metal nanoparticle catalysis by pulsed laser ablation Selim Senkan a,*, Michael online 18 July 2006 Abstract A high-throughput pulsed laser ablation (HT-PLA) system was developed-TEM) and energy dispersive X-ray (EDX) spectroscopy, respectively. The supported nanoparticles created by HT

Senkan, Selim M.

314

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser  

E-Print Network [OSTI]

Very-high-order harmonic generation from Ar atoms and Ar+ ions in superintense pulsed laser fields-high-order harmonic generation HHG from Ar atoms and Ar+ ions by means of the self-interaction-free time-order harmonic generation HHG is one of the most rapidly developing topics in the field of laser-atom molecule

Chu, Shih-I

315

The effect of dark matter resolution on the collapse of baryons in high redshift numerical simulations  

E-Print Network [OSTI]

We examine the impact of dark matter particle resolution on the formation of a baryonic core in high resolution adaptive mesh refinement simulations. We test the effect that both particle smoothing and particle splitting have on the hydrodynamic properties of a collapsing halo at high redshift (z > 20). Furthermore, we vary the background field intensity, with energy below the Lyman limit ( 100.0$ be satisfied, where ${M_{\\rm{core}}}$ is the enclosed baryon mass within the core and $M_{\\rm{DM}}$ is the minimum dark matter particle mass. This ratio should provide a very useful starting point for conducting convergence tests before any production run simulations. We find that dark matter particle smoothing is a useful adjunct to already highly resolved simulations.

Regan, John A; Wise, John H

2015-01-01T23:59:59.000Z

316

High-repetition-rate CF/sub 4/ laser  

SciTech Connect (OSTI)

A 16 ..mu..m CF/sub 4/ laser oscillator has operated at 1 kHz in a cooled static cell. Threshold pump energies required from the low pressure, Q-switched, cw discharge CO/sub 2/ laser were as low as 60 ..mu..J. The laser cavity employed the multiple-pass off-axis path resonator in a ring configuration. CF/sub 4/ laser power at 615 cm/sup -1/ and a 1 kHz repetition rate exceeded 300 ..mu..W.

Telle, J.

1981-01-01T23:59:59.000Z

317

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

is generated in electron storage rings when femtosecond lasers are used to carve out ultrafast x-ray pulses by femtoslicing (see "Tailored Terahertz Pulses from a...

318

High repetition rate fiber and integrated waveguide femtosecond lasers  

E-Print Network [OSTI]

Femtosecond lasers and the development of frequency combs have revolutionized multiple fields like metrology, spectroscopy, medical diagnostics and optical communications. However, to enable wider adoption of the technology ...

Sander, Michelle Y. (Michelle Yen-Ling)

2012-01-01T23:59:59.000Z

319

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11LargeLaser EnablesLaserLaserLaser

320

Structure of W3(OH) from Very High Spectral Resolution Observations of 5 Centimeter OH Masers  

E-Print Network [OSTI]

Recent studies of methanol and ground-state OH masers at very high spectral resolution have shed new light on small-scale maser processes. The nearby source W3(OH), which contains numerous bright masers in several different transitions, provides an excellent laboratory for high spectral resolution techniques. We present a model of W3(OH) based on EVN observations of the rotationally-excited 6030 and 6035 MHz OH masers taken at 0.024 km/s spectral resolution. The 6.0 GHz masers are becoming brighter with time and show evidence for tangential proper motions. We confirm the existence of a region of magnetic field oriented toward the observer to the southeast and find another such region to the northeast in W3(OH), near the champagne flow. The 6.0 GHz masers trace the inner edge of a counterclockwise rotating torus feature. Masers at 6030 MHz are usually a factor of a few weaker than at 6035 MHz but trace the same material. Velocity gradients of nearby Zeeman components are much more closely correlated than in the ground state, likely due to the smaller spatial separation between Zeeman components. Hydroxyl maser peaks at very long baseline interferometric resolution appear to have structure on scales both smaller than that resolvable as well as on larger scales.

Vincent L. Fish; Loránt O. Sjouwerman

2007-06-22T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

High mass resolution time of flight mass spectrometer for measuring products in heterogeneous catalysis in highly sensitive microreactors  

SciTech Connect (OSTI)

We demonstrate a combined microreactor and time of flight system for testing and characterization of heterogeneous catalysts with high resolution mass spectrometry and high sensitivity. Catalyst testing is performed in silicon-based microreactors which have high sensitivity and fast thermal response. Gas analysis is performed with a time of flight mass spectrometer with a modified nude Bayard-Alpert ionization gauge as gas ionization source. The mass resolution of the time of flight mass spectrometer using the ion gauge as ionization source is estimated to m/{Delta}m > 2500. The system design is superior to conventional batch and flow reactors with accompanying product detection by quadrupole mass spectrometry or gas chromatography not only due to the high sensitivity, fast temperature response, high mass resolution, and fast acquisition time of mass spectra but it also allows wide mass range (0-5000 amu in the current configuration). As a demonstration of the system performance we present data from ammonia oxidation on a Pt thin film showing resolved spectra of OH and NH{sub 3}.

Andersen, T.; Jensen, R.; Christensen, M. K.; Chorkendorff, I. [Department of Physics, Danish National Research Foundation's Center for Individual Nanoparticle Functionality (CINF), Technical University of Denmark, Building 312, DK-2800 Kgs. Lyngby (Denmark); Pedersen, T.; Hansen, O. [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech Building 345 East, DK-2800 Kgs. Lyngby (Denmark)

2012-07-15T23:59:59.000Z

322

A Simple Approach for Obtaining High Resolution, High Sensitivity ¹H NMR Metabolite Spectra of Biofluids with Limited Mass Supply  

SciTech Connect (OSTI)

A simple approach is reported that yields high resolution, high sensitivity ¹H NMR spectra of biofluids with limited mass supply. This is achieved by spinning a capillary sample tube containing a biofluid at the magic angle at a frequency of about 80Hz. A 2D pulse sequence called ¹H PASS is then used to produce a high-resolution ¹H NMR spectrum that is free from magnetic susceptibility induced line broadening. With this new approach a high resolution ¹H NMR spectrum of biofluids with a volume less than 1.0 µl can be easily achieved at a magnetic field strength as low as 7.05T. Furthermore, the methodology facilitates easy sample handling, i.e., the samples can be directly collected into inexpensive and disposable capillary tubes at the site of collection and subsequently used for NMR measurements. In addition, slow magic angle spinning improves magnetic field shimming and is especially suitable for high throughput investigations. In this paper first results are shown obtained in a magnetic field of 7.05T on urine samples collected from mice using a modified commercial NMR probe.

Hu, Jian Zhi; Rommereim, Donald N.; Wind, Robert A.; Minard, Kevin R.; Sears, Jesse A.

2006-11-01T23:59:59.000Z

323

Pulsed laser kinetic studies of liquids under high pressure  

SciTech Connect (OSTI)

A high pressure apparatus constructed for measuring the rates of reactions in liquids under pressures ranging from 1 atm to 2000 atm has been used to measure the complexation kinetics of molybdenum hexacarbonyl reacting with 2,2-bipyridine, 4,4{prime}-dimethyl-2-2{prime}-bipyridine and 4,4{prime}-diphenyl-2-2{prime} bipyridine in toluene. Pentacarbonyl reaction intermediates are created by a 10 nsec flash of frequency tripled Nd:YAG laser light. Measured activation volumes for chelate ligand ring closure indicate a change in mechanism from associative interchange to dissociative interchange as steric hindrance increases. A similar high pressure kinetics study of molybdenum carbonyl complexation by several substituted phenanthrolines is now well advanced that indicates that with the more rigid phenanthroline ligands steric effects from bulky substituents have less effect on the ring closure mechanism than in the case of the bipyridine ligands. An experimental concentration dependence of the fluorescence quantum yield of cresyl violet has been harmonized with previously published contradictory reports. Fluorescence of cresyl violet in various solvents and in micellar systems has also been systematically explored.

Eyring, E.M.

1991-11-25T23:59:59.000Z

324

Applications of high resolution ICP-AES in the nuclear industry  

SciTech Connect (OSTI)

Application of high resolution ICP-AES to selected problems of importance in the nuclear industry is a growing field. The advantages in sample preparation time, waste minimization and equipment cost are considerable. Two examples of these advantages are presented in this paper, burnup analysis of spent fuel and analysis of major uranium isotopes. The determination of burnup, an indicator of fuel cycle efficiency, has been accomplished by the determination of {sup 139}La by high resolution inductively coupled plasma atomic emission spectroscopy (HR-ICP-AES). Solutions of digested samples of reactor fuel rods were introduced into a shielded glovebox housing an inductively coupled plasma (ICP) and the resulting atomic emission transmitted to a high resolution spectrometer by a 31 meter fiber optic bundle. Total and isotopic U determination by thermal ionization mass spectrometry (TIMS) is presented to allow for the calculation of burnup for the samples. This method of burnup determination reduces the time, material, sample handling and waste generated associated with typical burnup determinations which require separation of lanthanum from the other fission products with high specific activities. Work concerning an alternative burnup indicator, {sup 236}U, is also presented for comparison. The determination of {sup 235}U:{sup 238}U isotope ratios in U-Zr fuel alloys is also presented to demonstrate the versatility of HR-ICP-AES.

Johnson, S.G.; Giglio, J.J.; Goodall, P.S.; Cummings, D.G.

1998-07-01T23:59:59.000Z

325

High spatial resolution brain functional MRI using submillimeter balanced steady-state free precession acquisition  

SciTech Connect (OSTI)

Purpose: One of the technical advantages of functional magnetic resonance imaging (fMRI) is its precise localization of changes from neuronal activities. While current practice of fMRI acquisition at voxel size around 3 × 3 × 3 mm{sup 3} achieves satisfactory results in studies of basic brain functions, higher spatial resolution is required in order to resolve finer cortical structures. This study investigated spatial resolution effects on brain fMRI experiments using balanced steady-state free precession (bSSFP) imaging with 0.37 mm{sup 3} voxel volume at 3.0 T. Methods: In fMRI experiments, full and unilateral visual field 5 Hz flashing checkerboard stimulations were given to healthy subjects. The bSSFP imaging experiments were performed at three different frequency offsets to widen the coverage, with functional activations in the primary visual cortex analyzed using the general linear model. Variations of the spatial resolution were achieved by removing outerk-space data components. Results: Results show that a reduction in voxel volume from 3.44 × 3.44 × 2 mm{sup 3} to 0.43 × 0.43 × 2 mm{sup 3} has resulted in an increase of the functional activation signals from (7.7 ± 1.7)% to (20.9 ± 2.0)% at 3.0 T, despite of the threefold SNR decreases in the original images, leading to nearly invariant functional contrast-to-noise ratios (fCNR) even at high spatial resolution. Activation signals aligning nicely with gray matter sulci at high spatial resolution would, on the other hand, have possibly been mistaken as noise at low spatial resolution. Conclusions: It is concluded that the bSSFP sequence is a plausible technique for fMRI investigations at submillimeter voxel widths without compromising fCNR. The reduction of partial volume averaging with nonactivated brain tissues to retain fCNR is uniquely suitable for high spatial resolution applications such as the resolving of columnar organization in the brain.

Wu, Pei-Hsin; Chung, Hsiao-Wen [Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China)] [Department of Electrical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Tsai, Ping-Huei [Imaging Research Center, Taipei Medical University, Taipei 11031, Taiwan and Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei 11031, Taiwan (China)] [Imaging Research Center, Taipei Medical University, Taipei 11031, Taiwan and Department of Medical Imaging, Taipei Medical University Hospital, Taipei Medical University, Taipei 11031, Taiwan (China); Wu, Ming-Long, E-mail: minglong.wu@csie.ncku.edu.tw [Institute of Medical Informatics, National Cheng-Kung University, Tainan 70101, Taiwan and Department of Computer Science and Information Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China)] [Institute of Medical Informatics, National Cheng-Kung University, Tainan 70101, Taiwan and Department of Computer Science and Information Engineering, National Cheng-Kung University, Tainan 70101, Taiwan (China); Chuang, Tzu-Chao [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China)] [Department of Electrical Engineering, National Sun Yat-Sen University, Kaohsiung 80424, Taiwan (China); Shih, Yi-Yu [Siemens Limited Healthcare Sector, Taipei 11503, Taiwan (China)] [Siemens Limited Healthcare Sector, Taipei 11503, Taiwan (China); Huang, Teng-Yi [Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China)] [Department of Electrical Engineering, National Taiwan University of Science and Technology, Taipei 10607, Taiwan (China)

2013-12-15T23:59:59.000Z

326

Development of High Resolution Land Surface Parameters for the Community Land Model  

SciTech Connect (OSTI)

There is a growing need for high-resolution land surface parameters as land surface models are being applied at increasingly higher spatial resolution offline as well as in regional and global models. The default land surface parameters for the most recent version of the Community Land Model (i.e. CLM 4.0) are at 0.5° or coarser resolutions, released with the Community Earth System Model (CESM). Plant Functional Types (PFTs), vegetation properties such as Leaf Area Index (LAI), Stem Area Index (SAI), and non-vegetated land covers were developed using remotely sensed datasets retrieved in late 1990’s and the beginning of this century. In this study, we developed new land surface parameters for CLM 4.0, specifically PFTs, LAI, SAI and non-vegetated land cover composition, at 0.05° resolution globally based on the most recent MODIS land cover and improved MODIS LAI products. Compared to the current CLM 4.0 parameters, the new parameters produced a decreased coverage by bare soil and trees, but an increased coverage by shrub, grass, and cropland. The new parameters result in a decrease in global seasonal LAI, with the biggest decrease in boreal forests; however, the new parameters also show a large increase in LAI in tropical forest. Differences between the new and the current parameters are mainly caused by changes in the sources of remotely sensed data and the representation of land cover in the source data. Advantages and disadvantages of each dataset were discussed in order to provide guidance on the use of the data. The new high-resolution land surface parameters have been used in a coupled land-atmosphere model (WRF-CLM) applied to the western U.S. to demonstrate their use in high-resolution modeling. A remapping method from the latitude/longitude grid of the CLM data to the WRF grids with map projection was also demonstrated. Future work will include global offline CLM simulations to examine the impacts of source data resolution and subsequent land parameter changes on simulated land surface processes.

Ke, Yinghai; Leung, Lai-Yung R.; Huang, Maoyi; Coleman, Andre M.; Li, Hongyi; Wigmosta, Mark S.

2012-11-06T23:59:59.000Z

327

High-frequency surface wave pumped He-Ne laser  

SciTech Connect (OSTI)

A new electrodeless He-Ne laser using a plasma produced by an electromagnetic surface wave as the active medium is described. Gain measurements are reported as a function of the pump wave frequency from 200 to 915 MHz. The dependence of laser performance on the gas mixture and pressure is also presented.

Moutoulas, C.; Moisan, M.; Bertrand, L.; Hubert, J.; Lachambre, J.L.; Ricard, A.

1985-02-15T23:59:59.000Z

328

The High Average Power Laser Program 15th HAPL meeting  

E-Print Network [OSTI]

. Georgia Tech 4. UCLA 5. U Rochester, LLE 6. UC Santa Barbara 7. UC Berkeley 8. UNC 9. Penn State Electro-optics Final opticsFinal optics #12;3 The HAPL program is developing two lasers: Diode Pumped Solid State Laser k continuous) Ceramic Honeycomb* "Primary" emitter *325 ppi cordierite honeycomb with gamma

329

High average power laser using a transverse flowing liquid host  

DOE Patents [OSTI]

A laser includes an optical cavity. A diode laser pumping device is located within the optical cavity. An aprotic lasing liquid containing neodymium rare earth ions fills the optical cavity. A circulation system that provides a closed loop for circulating the aprotic lasing liquid into and out of the optical cavity includes a pump and a heat exchanger.

Ault, Earl R.; Comaskey, Brian J.; Kuklo, Thomas C.

2003-07-29T23:59:59.000Z

330

High energy, high average power solid state green or UV laser  

DOE Patents [OSTI]

A system for producing a green or UV output beam for illuminating a large area with relatively high beam fluence. A Nd:glass laser produces a near-infrared output by means of an oscillator that generates a high quality but low power output and then multi-pass through and amplification in a zig-zag slab amplifier and wavefront correction in a phase conjugator at the midway point of the multi-pass amplification. The green or UV output is generated by means of conversion crystals that follow final propagation through the zig-zag slab amplifier.

Hackel, Lloyd A.; Norton, Mary; Dane, C. Brent

2004-03-02T23:59:59.000Z

331

Large High Resolution Displays for Co-Located Collaborative Sensemaking: Display Usage and Territoriality  

SciTech Connect (OSTI)

Large, high-resolution vertical displays carry the potential to increase the accuracy of collaborative sensemaking, given correctly designed visual analytics tools. From an exploratory user study using a fictional textual intelligence analysis task, we investigated how users interact with the display to construct spatial schemas and externalize information, as well as how they establish shared and private territories. We investigated the space management strategies of users partitioned by type of tool philosophy followed (visualization- or text-centric). We classified the types of territorial behavior exhibited in terms of how the users interacted with information on the display (integrated or independent workspaces). Next, we examined how territorial behavior impacted the common ground between the pairs of users. Finally, we offer design suggestions for building future co-located collaborative visual analytics tools specifically for use on large, high-resolution vertical displays.

Bradel, Lauren; Endert, Alexander; Koch, Kristen; Andrews, Christopher; North, Chris

2013-08-01T23:59:59.000Z

332

Indoor and Outdoor in Situ High-Resolution Gamma Radiation Measurements in Urban Areas of Cyprus  

E-Print Network [OSTI]

In situ, high-resolution, gamma-ray spectrometry of a total number of 70 outdoor and 20 indoor representative measurements were performed in preselected, common locations of the main urban areas of Cyprus. Specific activities and gamma absorbed dose rates in air due to the naturally occurring radionuclides of Th-232 and U-238 series, and K-40 are determined and discussed. Effective dose rate to the Cyprus population due to terrestrial gamma radiation is derived directly from this work. The results obtained outdoors match very well with those derived previously by high-resolution gamma spectrometry of soil samples, which were collected from the main island bedrock surface. This implies that the construction and building materials in urban areas do not affect the external gamma dose rate; thus they are mostly of local origin. Finally, the indoor/outdoor gamma dose ratio was found to be 1.4 +- 0.5.

Svoukis, E

2006-01-01T23:59:59.000Z

333

Superconducting gamma and fast-neutron spectrometers with high energy resolution  

DOE Patents [OSTI]

Superconducting Gamma-ray and fast-neutron spectrometers with very high energy resolution operated at very low temperatures are provided. The sensor consists of a bulk absorber and a superconducting thermometer weakly coupled to a cold reservoir, and determines the energy of the incident particle from the rise in temperature upon absorption. A superconducting film operated at the transition between its superconducting and its normal state is used as the thermometer, and sensor operation at reservoir temperatures around 0.1 K reduces thermal fluctuations and thus enables very high energy resolution. Depending on the choice of absorber material, the spectrometer can be configured either as a Gamma-spectrometer or as a fast-neutron spectrometer.

Friedrich, Stephan (San Jose, CA); , Niedermayr, Thomas R. (Oakland, CA); Labov, Simon E. (Berkeley, CA)

2008-11-04T23:59:59.000Z

334

Indoor and Outdoor in Situ High-Resolution Gamma Radiation Measurements in Urban Areas of Cyprus  

E-Print Network [OSTI]

In situ, high-resolution, gamma-ray spectrometry of a total number of 70 outdoor and 20 indoor representative measurements were performed in preselected, common locations of the main urban areas of Cyprus. Specific activities and gamma absorbed dose rates in air due to the naturally occurring radionuclides of Th-232 and U-238 series, and K-40 are determined and discussed. Effective dose rate to the Cyprus population due to terrestrial gamma radiation is derived directly from this work. The results obtained outdoors match very well with those derived previously by high-resolution gamma spectrometry of soil samples, which were collected from the main island bedrock surface. This implies that the construction and building materials in urban areas do not affect the external gamma dose rate; thus they are mostly of local origin. Finally, the indoor/outdoor gamma dose ratio was found to be 1.4 +- 0.5.

E. Svoukis; H. Tsertos

2006-10-02T23:59:59.000Z

335

Technologies and R&D for a High Resolution Cavity BPM for the CLIC Main Beam  

E-Print Network [OSTI]

The Main Beam (MB) linac of the Compact Linear Collider (CLIC) requires a beam orbit measurement system with high spatial (50 nm) and high temporal resolution (50 ns) to resolve the beam position within the 156 ns long bunch train, traveling on an energy-chirped, minimum dispersive trajectory. A 15 GHz prototype cavity BPM has been commissioned in the probe beam-line of the CTF3 CLIC Test Facility. We discuss performance and technical details of this prototype installation, including the 15 GHz analogue downconverter, the data acquisition and the control electronics and software. An R&D outlook is given for the next steps, which requires a system of 3 cavity BPMs to investigate the full resolution potential.

Towler, J R; Soby, L; Wendt, M; Boogert, S T; Cullinan, F J; Lyapin, A

2013-01-01T23:59:59.000Z

336

High-power terahertz optically pumped NH{sub 3} laser for plasma diagnostics  

SciTech Connect (OSTI)

The parameter of a terahertz (THz) laser intended for plasma diagnostics in electrodynamic accelerators and tokamaks with a strong magnetic field are discussed. Generation of THz radiation in an ammonia laser under the action of high-power pulsed optical pumping by the radiation of a 10P(32) CO{sub 2} laser is simulated numerically. The main characteristics of the output radiation, such as its spectrum, peak intensity, time dependence, and total energy, are calculated.

Mishchenko, V. A.; Petrushevich, Yu. V.; Sobolenko, D. N.; Starostin, A. N. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

2012-06-15T23:59:59.000Z

337

A proposal for testing subcritical vacuum pair production with high power lasers  

E-Print Network [OSTI]

We present a proposal for testing the prediction of non-equilibrium quantum field theory below the Schwinger limit. The proposed experiments should be able to detect a measurable number of gamma rays resulting from the annihilation of pairs in the focal spot of two opposing high intensity laser beams. We discuss the dependence of the expected number of gamma rays with the laser parameters and compare with the estimated background level of gamma hits for realistic laser conditions.

G. Gregori; D. B. Blaschke; P. P. Rajeev; H. Chen; R. J. Clarke; T. Huffman; C. D. Murphy; A. V. Prozorkevich; C. D. Roberts; G. Röpke; S. M. Schmidt; S. A. Smolyansky; S. Wilks; R. Bingham

2010-05-18T23:59:59.000Z

338

High-Resolution Genomic Profiles of Breast Cancer Cell Lines Assessed by Tiling BAC Array  

E-Print Network [OSTI]

number changes in 10 breast cancer cell lines (BT474, MCF7, HCC1937, SK-BR-3, L56Br-C1, ZR-75-1, JIMT1High-Resolution Genomic Profiles of Breast Cancer Cell Lines Assessed by Tiling BAC Array, MDA-MB-231, MDA-MB-361, and HCC2218) and one cell line derived from fibrocystic disease of the breast

Lunds Universitet,

339

High resolution neutron imaging of water in the polymer electrolyte fuel cell membrane  

SciTech Connect (OSTI)

Water transport in the ionomeric membrane, typically Nafion{reg_sign}, has profound influence on the performance of the polymer electrolyte fuel cell, in terms of internal resistance and overall water balance. In this work, high resolution neutron imaging of the Nafion{reg_sign} membrane is presented in order to measure water content and through-plane gradients in situ under disparate temperature and humidification conditions.

Mukherjee, Partha P [Los Alamos National Laboratory; Makundan, Rangachary [Los Alamos National Laboratory; Spendelow, Jacob S [Los Alamos National Laboratory; Borup, Rodney L [Los Alamos National Laboratory; Hussey, D S [NIST; Jacobson, D L [NIST; Arif, M [NIST

2009-01-01T23:59:59.000Z

340

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect (OSTI)

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall, G.E.

2011-05-31T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

High time resolution observations of the solar wind and backstreaming ions in the earth's foreshock region  

SciTech Connect (OSTI)

The interaction of the solar wind with ions backstreaming from the earth's bow shock is studied at high time resolution. It turns out that the bulk velocity of the solar wind oscillates, both in magnitude and direction, with typical periods of approx.1 minute in presence of the 'diffuse' ion population. Oscillations of comparable periods are also observed in the angular distribution and energy spectrum of the diffuse ions.

Formisano, V.; Orsini, S.; Bonifazi, C.; Egidi, A.; Moreno, G.

1980-05-01T23:59:59.000Z

342

A high-resolution, four-band SAR testbed with real-time image formation  

SciTech Connect (OSTI)

This paper describes the Twin-Otter SAR Testbed developed at Sandia National Laboratories. This SAR is a flexible, adaptable testbed capable of operation on four frequency bands: Ka, Ku, X, and VHF/UHF bands. The SAR features real-time image formation at fine resolution in spotlight and stripmap modes. High-quality images are formed in real time using the overlapped subaperture (OSA) image-formation and phase gradient autofocus (PGA) algorithms.

Walker, B.; Sander, G.; Thompson, M.; Burns, B.; Fellerhoff, R.; Dubbert, D.

1996-03-01T23:59:59.000Z

343

Gas-Phase Molecular Dynamics: High Resolution Spectroscopy and Collision Dynamics of Transient Species  

SciTech Connect (OSTI)

This research is carried out as part of the Gas-Phase Molecular Dynamics program in the Chemistry Department at Brookhaven National Laboratory. Chemical intermediates in the elementary gas-phase reactions involved in combustion chemistry are investigated by high resolution spectroscopic tools. Production, reaction, and energy transfer processes are investigated by transient, double resonance, polarization and saturation spectroscopies, with an emphasis on technique development and connection with theory, as well as specific molecular properties.

Hall G. E.; Goncharov, V.

2012-05-29T23:59:59.000Z

344

SUBARU HIGH-RESOLUTION SPECTROSCOPY OF COMPLEX METAL ABSORPTION LINES OF THE QUASAR HS 1603+38201  

E-Print Network [OSTI]

SUBARU HIGH-RESOLUTION SPECTROSCOPY OF COMPLEX METAL ABSORPTION LINES OF THE QUASAR HS 1603-resolution spectrum of the quasar HS 1603+3820 (zem = 2.542), observed with the High Dispersion Spectrograph -- quasars: individual (HS 1603+3820) 1. INTRODUCTION The bright quasar HS 1603+3820 (zem = 2.542, B = 15

Iye, Masanori

345

Hierarchical object-based classification of ultra-high-resolution digital mapping camera (DMC) imagery for rangeland mapping and assessment  

E-Print Network [OSTI]

and is in the process of changing from film to digital aerial image acquisition. Cur- rently, only broad land useHierarchical object-based classification of ultra-high-resolution digital mapping camera (DMC, MSC3JER, NMSU, Las Cruces, NM 88003-8003, USA Ultra-high-resolution digital aerial imagery has great

346

Impact of recent lake eutrophication on microbial community changes as revealed by high resolution lipid biomarkers in Rotsee (Switzerland)  

E-Print Network [OSTI]

Impact of recent lake eutrophication on microbial community changes as revealed by high resolution t The effects of eutrophication on short term changes in the microbial community were investigated using high resolution lipid biomarker and trace metal data for sediments from the eutrophic Lake Rotsee (Swit- zerland

Gilli, Adrian

347

The Double Seismic Zone of the Nazca Plate in Northern Chile: High Resolution Velocity Structure, Petrological Implications and  

E-Print Network [OSTI]

The Double Seismic Zone of the Nazca Plate in Northern Chile: High Resolution Velocity Structure presents an interdisciplinary study of the Northern Chile Double Seismic Zone. First, a high resolution method. The double seismic zone (DSZ) is observed between 80 and 140 km depth and the two seismic planes

Paris-Sud XI, Université de

348

Satellite data for high resolution offshore wind resource mapping: A data fusion approach M.B. Ben Ticha a,*  

E-Print Network [OSTI]

Satellite data for high resolution offshore wind resource mapping: A data fusion approach M.B. Ben accurate high spatial and temporal resolutions wind measurements. Offshore, satellite data are an accurate radar, scatterometer, data fusion, offshore wind energy resource assessment. 1. INTRODUCTION Since

Paris-Sud XI, Université de

349

Doped GdCl3 high resolution thermometers for use near to the lambda point , A.W. Harter  

E-Print Network [OSTI]

Doped GdCl3 high resolution thermometers for use near to the lambda point R.A.M. Lee a , A.2 K to 2.185 K. A paramagnetic salt thermometer was constructed using this salt and measurements were made of its sensitivity, noise and drift. 1 INTRODUCTION High-resolution thermometers (HRTs) were

Goodstein, David

350

Forensic palmprint recognition, which mainly deals with high-resolution palmprints and latent-to-full palmprint  

E-Print Network [OSTI]

Abstract Forensic palmprint recognition, which mainly deals with high-resolution palmprints of the evidence of palmprints in forensics. There are some in-depth works on high-resolution palmprint comparison algorithm was proposed as it has been proposed for forensic likelihood ratio computation using

Autonoma de Madrid, Universidad

351

High-resolution stratospheric tracer fields estimated from satellite observations using Lagrangian trajectory calculations  

SciTech Connect (OSTI)

A technique is introduced by which high-resolution tracer fields may be constructed from low-resolution satellite observations. The technique relies upon the continual cascade of tracer variance from large to small scales and makes use of wind fields generated by a data assimilation scheme. To demonstrate its usefulness, the technique has been applied in a study of isentropic distributions of nitrous oxide in the winter midstratosphere, using measurements made by the Improved Stratospheric and Mesospheric Sounder (ISAMS) instrument on the Upper Atmosphere Research Satellite (UARS). The results show that the high-resolution fields significantly increase the amount of information that is available from the satellite observations. The fields give insights into the characteristic structure and evolution of tracer distributions at scales that are normally obscured from view. Two results are particularly noteworthy. First, at the interface between low and middle latitudes there is evidence of active mixing. This mixing occurs on the eastern, equatorward side of air that is being drawn toward high latitudes around the polar vortex. Second, in the anticyclone, a complex pattern of transport is revealed. Air drawn in from low latitudes spirals together with ambient midlatitude air. Small scales are generated relatively slowly in the organized flow, and persistent filamentary structures, with transverse scales of hundreds of kilometers or greater, are seen.

Sutton, R.T.; Maclean, H.; Swinbank, R.; O`Neill, A.; Taylor, F.W. [Oxford Univ., Oxford (United Kingdom)] [Oxford Univ., Oxford (United Kingdom); [Meteorological Office, Bracknell, Berkshire (United Kingdom); [Univ. of Reading, Reading (United Kingdom)

1994-10-01T23:59:59.000Z

352

Advances of plasma diagnostics with high-resolution spectroscopy of stellar coronae  

E-Print Network [OSTI]

X-ray emission from cool stars is an important tracer for stellar activity. The X-ray luminosity reflects different levels of activity and covers four orders of magnitude in stars of spectral types M-F. Low spectral resolution provided by X-ray observations of stellar coronae in the past allowed the determination of temperature distributions and elemental abundances making use of atomic databases (listing line emissivities and bremsstrahlung continuum for a given temperature structure). The new missions XMM-Newton and Chandra carry X-ray gratings providing sufficient spectral resolution to measure the fluxes of strategic emission lines. I describe the different approaches applicable to low-resolution and high-resolution spectra, especially focusing on the new grating spectra with X-ray lines. From only a few lines it is possible to determine plasma temperatures and associated densities, to check for any effects from resonant scattering, and to identify particular abundance anomalies. Line-based temperature- and density measurements represent only a fraction of the total plasma, but the pressure environment of different fractions can be probed simply by selection of specific lines. Selected results are presented covering all aspects of line-based analyses.

J. -U. Ness

2005-04-06T23:59:59.000Z

353

Application of Spatially Resolved High Resolution Crystal Spectrometry to ICF Plasmas  

SciTech Connect (OSTI)

High resolution (?/?#3;? ~ 10 000) 1D imaging x-ray spectroscopy using a spherically bent crystal and a 2D hybrid pixel array detector is used world wide for Doppler measurements of ion-temperature and plasma flow-velocity profiles in magnetic confinement fusion plasmas. Meter sized plasmas are diagnosed with cm spatial resolution and 10 ms time resolution. This concept can also be used as a diagnostic of small sources, such as inertial confinement fusion plasmas and targets on x-ray light source beam lines, with spatial resolution of micrometers, as demonstrated by laboratory experiments using a 250-?m 55 Fe source, and by ray-tracing calculations. Throughput calculations agree with measurements, and predict detector counts in the range 10-8 -10-6 times source x-rays, depending on crystal reflectivity and spectrometer geometry. Results of the lab demonstrations, application of the technique to the National Ignition Facility (NIF), and predictions of performance on NIF will be presented.

Kenneth W. Hill, et. al.

2012-09-15T23:59:59.000Z

354

The Importance of High Temporal Resolution in Modeling Renewable Energy Penetration Scenarios  

SciTech Connect (OSTI)

Traditionally, modeling investment and dispatch problems in electricity economics has been limited by computation power. Due to this limitation, simplifications are applied. One common practice, for example, is to reduce the temporal resolution of the dispatch by clustering similar load levels. The increase of intermittent electricity from renewable energy sources (RES-E) changes the validity of this assumption. RES-E already cover a certain amount of the total demand. This leaves an increasingly volatile residual demand to be matched by the conventional power market. This paper quantifies differences in investment decisions by applying three different time-resolution residual load patterns in an investment and dispatch power system model. The model optimizes investment decisions in five year steps between today and 2030 with residual load levels for 8760, 288 and 16 time slices per year. The market under consideration is the four zone ERCOT market in Texas. The results show that investment decisions significantly differ across the three scenarios. In particular, investments into base-load technologies are substantially reduced in the high resolution scenario (8760 residual load levels) relative to the scenarios with lower temporal resolution. Additionally, the amount of RES-E curtailment and the market value of RES-E exhibit noteworthy differences.

Nicolosi, Marco; Mills, Andrew D; Wiser, Ryan H

2010-10-08T23:59:59.000Z

355

Simultaneous High-Resolution 2-Dimensional Spatial and 1-Dimensional Picosecond Streaked X-ray Pinhole Imaging  

SciTech Connect (OSTI)

A Kentech x-ray streak camera was run at the LLNL Compact Multipulse Terawatt (COMET) laser to record simultaneous space- and time-resolved measurements of picosecond laser-produced plasmas. Four different x-ray energy channels were monitored using broad-band filters to record the time history of Cu targets heated at irradiances of 10{sup 16} - 10{sup 19} W/cm{sup 2}. Through the Cu filter channel, a time-resolution below 3ps was obtained. Additionally, an array of 10 {micro}m diameter pinholes was placed in front of the camera to produce multiple time-resolved x-ray images on the photocathode and time-integrated images on the phosphor with 10 and 15 times magnification, respectively, with spatial resolution of <13 {micro}m.

Steel, A B; Nagel, S R; Dunn, J; Baldis, H A

2012-05-03T23:59:59.000Z

356

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11LargeLaserLaser Seeding YieldsLaser

357

High-Power Laser Pulse Recirculation for Inverse Compton Scattering-Produced Gamma-Rays  

SciTech Connect (OSTI)

Inverse Compton scattering of high-power laser pulses on relativistic electron bunches represents an attractive method for high-brightness, quasi-monoenergetic {gamma}-ray production. The efficiency of {gamma}-ray generation via inverse Compton scattering is severely constrained by the small Thomson scattering cross section. Furthermore, repetition rates of high-energy short-pulse lasers are poorly matched with those available from electron accelerators, resulting in low repetition rates for generated {gamma}-rays. Laser recirculation has been proposed as a method to address those limitations, but has been limited to only small pulse energies and peak powers. Here we propose and experimentally demonstrate an alternative method for laser pulse recirculation that is uniquely capable of recirculating short pulses with energies exceeding 1 J. Inverse Compton scattering of recirculated Joule-level laser pulses has a potential to produce unprecedented peak and average {gamma}-ray brightness in the next generation of sources.

Jovanovic, I; Shverdin, M; Gibson, D; Brown, C

2007-04-17T23:59:59.000Z

358

High Average Power Laser Gain Medium With Low Optical Distortion Using A Transverse Flowing Liquid Host  

DOE Patents [OSTI]

A high average power, low optical distortion laser gain media is based on a flowing liquid media. A diode laser pumping device with tailored irradiance excites the laser active atom, ion or molecule within the liquid media. A laser active component of the liquid media exhibits energy storage times longer than or comparable to the thermal optical response time of the liquid. A circulation system that provides a closed loop for mixing and circulating the lasing liquid into and out of the optical cavity includes a pump, a diffuser, and a heat exchanger. A liquid flow gain cell includes flow straighteners and flow channel compression.

Comaskey, Brian J. (Walnut Creek, CA); Ault, Earl R. (Livermore, CA); Kuklo, Thomas C. (Oakdale, CA)

2005-07-05T23:59:59.000Z

359

A high spatial resolution Stokes polarimeter for motional Stark effect imaging  

SciTech Connect (OSTI)

We describe an enhanced temporally switched interfero-polarimeter that has been successfully deployed for high spatial resolution motional Stark effect imaging on the KSTAR superconducting tokamak. The system utilizes dual switching ferroelectric liquid crystal waveplates to image the full Stokes vector of elliptically polarized and Doppler-shifted Stark-Zeeman Balmer-alpha emission from high energy neutral beams injected into the magnetized plasma. We describe the optical system and compare its performance against a Mueller matrix model that takes account of non-ideal performance of the switching ferro-electric liquid crystal waveplates and other polarizing components.

Thorman, Alex; Michael, Clive; Howard, John [Plasma Research Laboratory, Research School of Physics and Engineering, Australian National University, Canberra ACT 0200 (Australia)

2013-06-15T23:59:59.000Z

360

High power single-crystal fiber CW 946 nm laser and blue generation based on Rubidium-doped PPKTP  

E-Print Network [OSTI]

for high power, continuous wave and polarized laser at 946 nm (fig1.c). We demonstrate a polarized laser. Laurell, "High-power, continous-wave, second harmonic generation at 532 nm in periodically poled KTiOPO4(b)(a) (c) High power single-crystal fiber CW 946 nm laser and blue generation based on Rubidium

Boyer, Edmond

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

A design for a high resolution very-low-Q time-of flight diffractometer.  

SciTech Connect (OSTI)

The design of a high resolution view low-Q time of flight diffractometer was motivated by the anticipated need to perform small-angle neutron scattering measurements at far lower momentum transfer and higher precision than currently available at either pulsed or steady state sources. In addition, it was recognized that flexibility in the configuration of the instrument and ease in which data is acquired are important. The design offers two configurations, a high intensity/very low Q geometry employing a focusing mirror and a medium to high Q-precision/low Q configuration using standard pinhole collimation geometry. The quality of the mirror optics is very important to the performance of the high intensity/very low Q configuration. We believe that the necessary technology exists to fabricate the high quality mirror optics required for the instrument.

Hjelm, R. P.

1998-09-29T23:59:59.000Z

362

High intensity picosecond Fourier limited pulses : design of a synchronously pumped dye laser system  

E-Print Network [OSTI]

527 High intensity picosecond Fourier limited pulses : design of a synchronously pumped dye laser picosecond pulses. A Nd : Yag picosecond laser is used to synchronously pump a dye oscillator/amplifier system. The dye oscillator is of the Littman type. Up to 1.5 mJ of energy is obtained in a 20 ps pulse

Paris-Sud XI, Université de

363

High energy density micro plasma bunch from multiple laser interaction with thin target  

SciTech Connect (OSTI)

Three-dimensional particle-in-cell simulation is used to investigate radiation-pressure driven acceleration and compression of small solid-density plasma by intense laser pulses. It is found that multiple impacts by presently available short-pulse lasers on a small hemispheric shell target can create a long-living tiny quasineutral monoenergetic plasma bunch of very high energy density.

Xu, Han [National Laboratory for Parallel and Distributed Processing, College of Computer Science, National University of Defense Technology, Changsha 410073 (China); Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, Wei; Luan, S. X.; Xu, Z. Z. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Yu, M. Y., E-mail: myyu@zju.edu.cn [Physics Department, Institute for Fusion Theory and Simulation, Zhejiang University, Hangzhou 310027 (China); Institute for Theoretical Physics I, Ruhr University, Bochum D-44780 (Germany); Cai, H. B.; Zhou, C. T. [Institute of Applied Physics and Computational Mathematics, Beijing 100088 (China); Yang, X. H.; Yin, Y.; Zhuo, H. B. [College of Science, National University of Defense Technology, Changsha (China); Wang, J. W. [Shanghai Institute of Optics and Fine Mechanics, Shanghai 201800 (China); Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan); Murakami, M. [Institute of Laser Engineering, Osaka University, Osaka 565-0871 (Japan)

2014-01-13T23:59:59.000Z

364

Fiber Bragg grating inscription by high-intensity femtosecond UV laser light: comparison  

E-Print Network [OSTI]

Fiber Bragg grating inscription by high-intensity femtosecond UV laser light: comparison with other 264-nm laser light and a phase mask technique, Bragg grating inscription in a range of different, that result in a significant photosensitivity enhancement of the in- vestigated fibers in comparison

Nikogosyan, David N.

365

Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration Data  

E-Print Network [OSTI]

Application of High-performance Visual Analysis Methods to Laser Wakefield Particle Acceleration, time- varying laser wakefield particle accelerator simulation data. We ex- tend histogramBit, a state-of-the-art index/query technology, to acceler- ate data mining and multi-dimensional histogram

366

The National Ignition Facility National Ignition Campaign Short Pulse Lasers High-Average-Power Laser  

E-Print Network [OSTI]

-Average-Power Laser NIF-1005-11471 07BEW/dj P9765 Agenda #12;P9516NIF-0805-11197 01EIM/dj Stockpile Stewardship #12;P9504NIF-0404-08345r2 27EIM/ld Basic Science and Cosmology #12;NIF-0702-05346rIFSA Fusion Energy Campaign and point design NIF-0305-10564 23MLS/cld P8719 The NIF Laser User Optics Physics Operations

367

Method for optical pumping of thin laser media at high average power  

DOE Patents [OSTI]

A thin, planar laser material is bonded to a light guide of an index-matched material forming a composite disk. Diode array or other pump light is introduced into the composite disk through the edges of the disk. Pump light trapped within the composite disk depletes as it multi-passes the laser medium before reaching an opposing edge of the disk. The resulting compound optical structure efficiently delivers concentrated pump light and to a laser medium of minimum thickness. The external face of the laser medium is used for cooling. A high performance cooler attached to the external face of the laser medium rejects heat. Laser beam extraction is parallel to the heat flux to minimize optical distortions.

Zapata, Luis E. (Livermore, CA); Beach, Raymond J. (Livermore, CA); Honea, Eric C. (Sunol, CA); Payne, Stephen A. (Castro Valley, CA)

2004-07-13T23:59:59.000Z

368

Characterization and analysis of highly diagonal Terahertz Quantum Cascade Lasers  

E-Print Network [OSTI]

The as yet unattained milestone of room-temperature operation is essential for establishing Terahertz Quantum Cascade Lasers (THz QCLs) as practical sources of THz radiation. Temperature performance is hypothesized to be ...

Chan, Chun Wang Ivan

2010-01-01T23:59:59.000Z

369

High-Resolution Structure of the Photosynthetic Mn4Ca Catalyst from X-ray Spectroscopy  

SciTech Connect (OSTI)

The application of high-resolution X-ray spectroscopy methods to study the photosynthetic water oxidizing complex, which contains a unique hetero-nuclear catalytic Mn4Ca cluster, are described. Issues of X-ray damage especially at the metal sites in the Mn4Ca cluster are discussed. The structure of the Mn4Ca catalyst at high-resolution which has so far eluded attempts of determination by X-ray diffraction, EXAFS and other spectroscopic techniques has been addressed using polarized EXAFS techniques applied to oriented PS II membrane preparations and PS II single crystals. A review of how the resolution of traditional EXAFS techniques can be improved, using methods such as range-extended EXAFS is presented, and the changes that occur in the structure of the cluster as it advances through the catalytic cycle are described. X-ray absorption and emission techniques (XANES and K? emission) have been used earlier to determine the oxidation states of the Mn4Ca cluster, and in this report we review the use of X-ray resonant Raman spectroscopy to understand the electronic structure of the Mn4Ca cluster as it cycles through the intermediate S-states.

Yachandra, Vittal; Yano, Junko; Kern, Jan; Pushkar, Yulia; Sauer, Kenneth; Glatzel, Pieter; Bergmann, Uwe; Messinger, Johannes; Zouni, Athina; Yachandra, Vittal K.

2007-08-01T23:59:59.000Z

370

High efficiency resonance ionization mass spectrometric analysis by external laser cavity enhancement techniques  

SciTech Connect (OSTI)

The demand to measure high dynamic range isotope ratios on small samples with resonance ionization mass spectrometry (RIMS) continues to increase. This paper discusses high ionization efficiency methods which can be applied to continuous wave (cw) RIMS to potentially achieve several tens of percent ionization efficiencies for certain elements. The primary technique under development to achieve this is an external laser cavity which can generate very high circulating laser powers. 12 refs., 3 figs.

Johnson, S.G.; Rios, E.L.; Miller, C.M.; Fearey, B.L.

1991-01-01T23:59:59.000Z

371

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformationPostdocs space CombinedValuesRevolutionizingLaserLaser

372

High resolution simulations of ignition capsule designs for the National Ignition Facility  

SciTech Connect (OSTI)

Ignition capsule designs for the National Ignition Facility (NIF) [G. H. Miller, E. I. Moses, and C. R. Wuest, Opt. Eng. 443, 2841 (2004)] have continued to evolve in light of improved physical data inputs, improving simulation techniques, and - most recently - experimental data from a growing number of NIF sub-ignition experiments. This paper summarizes a number of recent changes to the cryogenic capsule design and some of our latest techniques in simulating its performance. Specifically, recent experimental results indicated harder x-ray drive spectra in NIF hohlraums than were predicted and used in previous capsule optimization studies. To accommodate this harder drive spectrum, a series of high-resolution 2-D simulations, resolving Legendre mode numbers as high as two thousand, were run and the germanium dopant concentration and ablator shell thicknesses re-optimized accordingly. Simultaneously, the possibility of cooperative or nonlinear interaction between neighboring ablator surface defects has motivated a series of fully 3-D simulations run with the massively parallel HYDRA code. These last simulations include perturbations seeded on all capsule interfaces and can use actual measured shell surfaces as initial conditions. 3-D simulations resolving Legendre modes up to two hundred on large capsule sectors have run through ignition and burn, and higher resolution simulations resolving as high as mode twelve hundred have been run to benchmark high-resolution 2-D runs. Finally, highly resolved 3-D simulations have also been run of the jet-type perturbation caused by the fill tube fitted to the capsule. These 3-D simulations compare well with the more typical 2-D simulations used in assessing the fill tube's impact on ignition. Coupled with the latest experimental inputs from NIF, our improving simulation capability yields a fuller and more accurate picture of NIF ignition capsule performance.

Clark, D S; Haan, S W; Cook, A W; Edwards, M J; Hammel, B A; Koning, J M; Marinak, M M

2011-02-17T23:59:59.000Z

373

Short range, ultra-wideband radar with high resolution swept range gate  

DOE Patents [OSTI]

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control.

McEwan, Thomas E. (Livermore, CA)

1998-05-26T23:59:59.000Z

374

Ultra-high-resolution alpha spectrometry for nuclear forensics and safeguards applications  

SciTech Connect (OSTI)

We will present our work on the development of ultra-high-resolution detectors for alpha particle spectrometry. These detectors, based on superconducting transition-edge sensors, offer energy resolution that is five to ten times better than conventional silicon detectors. Using these microcalorimeter detectors, the isotopic composition of mixed-actinide samples can be determined rapidly without the need for actinide separation chemistry to isolate each element, or mass spectrometry to separate isotopic signatures that can not be resolved using traditional alpha spectrometry (e.g. Pu-239/Pu-240, or Pu-238/Am-241). This paper will cover the detector and measurement system, actinide source preparation, and the quantitative isotopic analysis of a number of forensics- and safeguards-relevant radioactive sources.

Bacrania, Minesh K [Los Alamos National Laboratory; Croce, Mark [Los Alamos National Laboratory; Bond, Evelyn [Los Alamos National Laboratory; Dry, Donald [Los Alamos National Laboratory; Moody, W. Allen [Los Alamos National Laboratory; Lamont, Stephen [Los Alamos National Laboratory; Rabin, Michael [Los Alamos National Laboratory; Rim, Jung [Los Alamos National Laboratory; Smith, Audrey [Los Alamos National Laboratory; Beall, James [NIST-BOULDER; Bennett, Douglas [NIST-BOULDER; Kotsubo, Vincent [NIST-BOULDER; Horansky, Robert [NIST-BOULDER; Hilton, Gene [NIST-BOULDER; Schmidt, Daniel [NIST-BOULDER; Ullom, Joel [NIST-BOULDER; Cantor, Robin [STAR CRYOELECTRONICS

2010-01-01T23:59:59.000Z

375

New developments in high resolution borehole seismology and their applications to reservoir development and management  

SciTech Connect (OSTI)

Single-well seismology, Reverse Vertical Seismic Profiles (VSP`s) and Crosswell seismology are three new seismic techniques that we jointly refer to as borehole seismology. Borehole seismic techniques are of great interest because they can obtain much higher resolution images of oil and gas reservoirs than what is obtainable with currently used seismic techniques. The quality of oil and gas reservoir management decisions depend on the knowledge of both the large and the fine scale features in the reservoirs. Borehole seismology is capable of mapping reservoirs with an order of magnitude improvement in resolution compared with currently used technology. In borehole seismology we use a high frequency seismic source in an oil or gas well and record the signal in the same well, in other wells, or on the surface of the earth.

Paulsson, B.N.P. [Chevron Petroleum Technology Company, La Habra, CA (United States)

1997-08-01T23:59:59.000Z

376

The High-Resolution Lightweight Telescope for the EUV (HiLiTE)  

SciTech Connect (OSTI)

The High-resolution Lightweight Telescope for the EUV (HiLiTE) is a Cassegrain telescope that will be made entirely of Silicon Carbide (SiC), optical substrates and metering structure alike. Using multilayer coatings, this instrument will be tuned to operate at the 465 {angstrom} Ne VII emission line, formed in solar transition region plasma at {approx}500,000 K. HiLiTE will have an aperture of 30 cm, angular resolution of {approx}0.2 arc seconds and operate at a cadence of {approx}5 seconds or less, having a mass that is about 1/4 that of one of the 20 cm aperture telescopes on the Atmospheric Imaging Assembly (AIA) instrument aboard NASA's Solar Dynamics Observatory (SDO). This new instrument technology thus serves as a path finder to a post-AIA, Explorer-class missions.

Martinez-Galarce, D S; Boerner, P; Soufli, R; De Pontieu, B; Katz, N; Title, A; Gullikson, E M; Robinson, J C; Baker, S L

2008-06-02T23:59:59.000Z

377

High-resolution x-ray diffraction microscopy of specifically labeled yeast cells  

DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

X-ray diffraction microscopy complements other x-ray microscopy methods by being free of lens-imposed radiation dose and resolu- tion limits, and it allows for high-resolution imaging of biological specimens too thick to be viewed by electron microscopy. We report here the highest resolution (11–13 nm) x-ray diffraction micrograph of biological specimens, and a demonstration of mole- cular-specific gold labeling at different depths within cells via through-focus propagation of the reconstructed wavefield. The lec- tin concanavalin A conjugated to colloidal gold particles was used to label the ?-mannan sugar in the cell wall of the yeast Saccharomyces cerevisiae. Cells were plunge-frozen in liquid ethane and freeze-dried, after which they were imaged whole using x-ray diffraction microscopy at 750 eV photon energy.

Nelson, J.; Huang, X.; Steinbrener, J.; Shapiro, D.; Kirz, J.; Marchesini, S.; Neiman, A. M.; Turner, J. J.; Jacobsen, C.

2010-04-20T23:59:59.000Z

378

Short range, ultra-wideband radar with high resolution swept range gate  

DOE Patents [OSTI]

A radar range finder and hidden object locator is based on ultra-wide band radar with a high resolution swept range gate. The device generates an equivalent time amplitude scan with a typical range of 4 inches to 20 feet, and an analog range resolution as limited by a jitter of on the order of 0.01 inches. A differential sampling receiver is employed to effectively eliminate ringing and other aberrations induced in the receiver by the near proximity of the transmit antenna, so a background subtraction is not needed, simplifying the circuitry while improving performance. Uses of the invention include a replacement of ultrasound devices for fluid level sensing, automotive radar, such as cruise control and parking assistance, hidden object location, such as stud and rebar finding. Also, this technology can be used when positioned over a highway lane to collect vehicle count and speed data for traffic control. 14 figs.

McEwan, T.E.

1998-05-26T23:59:59.000Z

379

Measurement of low radioactivity background in a high voltage cable by high resolution inductively coupled plasma mass spectrometry  

SciTech Connect (OSTI)

The measurement of naturally occurring low level radioactivity background in a high voltage (HV) cable by high resolution inductively coupled plasma mass spectrometry (HR ICP MS) is presented in this work. The measurements were performed at the Chemistry Service of the Gran Sasso National Laboratory. The contributions to the radioactive background coming from the different components of the heterogeneous material were separated. Based on the mass fraction of the cable, the whole contamination was calculated. The HR ICP MS results were cross-checked by gamma ray spectroscopy analysis that was performed at the low background facility STELLA (Sub Terranean Low Level Assay) of the LNGS underground lab using HPGe detectors.

Vacri, M. L. di; Nisi, S.; Balata, M. [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)] [Gran Sasso National Laboratory, Chemistry Service, SS 17bis km 18.910, 67100 Assergi (Aq) (Italy)

2013-08-08T23:59:59.000Z

380

High energy bursts from a solid state laser operated in the heat capacity limited regime  

DOE Patents [OSTI]

High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes. 5 figs.

Albrecht, G.; George, E.V.; Krupke, W.F.; Sooy, W.; Sutton, S.B.

1996-06-11T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

High energy bursts from a solid state laser operated in the heat capacity limited regime  

DOE Patents [OSTI]

High energy bursts are produced from a solid state laser operated in a heat capacity limited regime. Instead of cooling the laser, the active medium is thermally well isolated. As a result, the active medium will heat up until it reaches some maximum acceptable temperature. The waste heat is stored in the active medium itself. Therefore, the amount of energy the laser can put out during operation is proportional to its mass, the heat capacity of the active medium, and the temperature difference over which it is being operated. The high energy burst capacity of a heat capacity operated solid state laser, together with the absence of a heavy, power consuming steady state cooling system for the active medium, will make a variety of applications possible. Alternately, cooling takes place during a separate sequence when the laser is not operating. Industrial applications include new material working processes.

Albrecht, Georg (Livermore, CA); George, E. Victor (Livermore, CA); Krupke, William F. (Pleasanton, CA); Sooy, Walter (Pleasanton, CA); Sutton, Steven B. (Manteca, CA)

1996-01-01T23:59:59.000Z

382

A Laser System for the Spectroscopy of Highly-Charged Bismuth Ions  

E-Print Network [OSTI]

We present and characterize a laser system for the spectroscopy on highly-charged ^209Bi^82+ ions at a wavelength of 243.87 nm. For absolute frequency stabilization, the laser system is locked to a near-infra-red laser stabilized to a rubidium transition line using a transfer cavity based locking scheme. Tuning of the output frequency with high precision is achieved via a tunable rf offset lock. A sample-and-hold technique gives an extended tuning range of several THz in the UV. This scheme is universally applicable to the stabilization of laser systems at wavelengths not directly accessible to atomic or molecular resonances. We determine the frequency accuracy of the laser system using Doppler-free absorption spectroscopy of Te_2 vapour at 488 nm. Scaled to the target wavelength of 244 nm, we achieve a frequency uncertainty of \\sigma_{244nm} = 6.14 MHz (one standard deviation) over six days of operation.

S. Albrecht; S. Altenburg; C. Siegel; N. Herschbach; G. Birkl

2011-08-25T23:59:59.000Z

383

The DOE Program in High Energy Density New Initiatives in Matter in Extreme Conditions  

E-Print Network [OSTI]

resolution (seeded beam) · High wavenumber resolution (x-ray laser) · High temporal resolution (20-50 fs Meeting and Symposium #12;2 Outline · LCLS Free Electron Laser facility. - Unprecedented capabilities at the MEC instrument [since 4/2012] · 1012 x-ray photons for pump-prober experiments · High spectral

384

High efficiency 2 micrometer laser utilizing wing-pumped Tm.sup.3+ and a laser diode array end-pumping architecture  

DOE Patents [OSTI]

Wing pumping a Tm.sup.3+ doped, end pumped solid state laser generates 2 .mu.m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm.sup.3+ absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm.sup.3+ because high Tm.sup.3+ concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation.

Beach, Raymond J. (Livermore, CA)

1997-01-01T23:59:59.000Z

385

High efficiency 2 micrometer laser utilizing wing-pumped Tm{sup 3+} and a laser diode array end-pumping architecture  

DOE Patents [OSTI]

Wing pumping a Tm{sup 3+} doped, end pumped solid state laser generates 2 {micro}m laser radiation at high average powers with high efficiency. Using laser diode arrays to end-pump the laser rod or slab in the wing of the Tm{sup 3+} absorption band near 785 nm results in 2-for-1 quantum efficiency in Tm{sup 3+} because high Tm{sup 3+} concentrations can be used. Wing pumping allows the thermal power generated in the rod or slab to be distributed over a large enough volume to make thermal management practical in the laser gain medium even at high average power operation. The approach is applicable to CW, Q-switched, and rep-pulsed free-laser operation. 7 figs.

Beach, R.J.

1997-11-18T23:59:59.000Z

386

Integration of photonic and passive microfluidic devices into lab-on-chip with femtosecond laser materials processing  

E-Print Network [OSTI]

Femtosecond laser materials processing is a powerful method for the integration of high resolution, 3D structures into Lab-On-Chip (LOC) systems. One major application of femtosecond laser materials processing is waveguide ...

Gu, Yu, Ph.D. Massachusetts Institute of Technology

2011-01-01T23:59:59.000Z

387

THE USE OF THE HIGH RESOLUTION VISIBLE IN SAFNWC/MSG Marcel Derrien, Herv Le Glau, Marie-Paule Raoul  

E-Print Network [OSTI]

in this paper is an output of this task. HRV IMAGERY CHARACTERISTICS SEVIRI has one high resolution (HRes) broadband solar channel (0.3-1.1 m) and 11 lower resolution (LRes) channels; 3 narrowband solar channels (0 scheme of HRV data.

Boyer, Edmond

388

High repetition rate mode-locked erbium-doped fiber lasers with complete electric field control  

E-Print Network [OSTI]

Recent advances in fully-stabilized mode-locked laser systems are enabling many applications, including optical arbitrary waveform generation (OAWG). In this thesis work, we describe the development of high repetition-rate ...

Sickler, Jason William, 1978-

2008-01-01T23:59:59.000Z

389

A high carrier injection terahertz quantum cascade laser based on indirectly pumped scheme  

E-Print Network [OSTI]

A Terahertz quantum cascade laser with a rather high injection coupling strength based on an indirectly pumped scheme is designed and experimentally implemented. To effectively suppress leakage current, the chosen quantum ...

Razavipour, S. G.

390

Femtosecond fiber lasers at 1550 nm for high repetition rates and low timing jitter  

E-Print Network [OSTI]

Femtosecond fiber lasers have become an important enabling technology for advances in many areas including: frequency combs, precise timing distribution, optical arbitrary waveform generation, and high bit rate sampling ...

Morse, Jonathan Lee

2013-01-01T23:59:59.000Z

391

High-resolution inverse Raman and resonant-wave-mixing spectroscopy  

SciTech Connect (OSTI)

These research activities consist of high-resolution inverse Raman spectroscopy (IRS) and resonant wave-mixing spectroscopy to support the development of nonlinear-optical techniques for temperature and concentration measurements in combustion research. Objectives of this work include development of spectral models of important molecular species needed to perform coherent anti-Stokes Raman spectroscopy (CARS) measurements and the investigation of new nonlinear-optical processes as potential diagnostic techniques. Some of the techniques being investigated include frequency-degenerate and nearly frequency-degenerate resonant four-wave-mixing (DFWM and NDFWM), and resonant multi-wave mixing (RMWM).

Rahn, L.A. [Sandia National Laboratories, Livermore, CA (United States)

1993-12-01T23:59:59.000Z

392

High-resolution methods for preserving the sum of mass fractions: improved ?-scheme and an alternative  

SciTech Connect (OSTI)

When high resolution convection schemes are used for discretizing chemical species mass balance equations, the mass fractions are not guaranteed to add to one. We show that a proposed remedy called ?-scheme (Darwish and Moukalled, Comput.Methods Appl.Mech. Engrg. 192 (2003): 1711) will degrade to a diffusive first-order scheme when a chemical species vanishes from the mixture, for example, because of chemical reactions. We propose an improvement to the ?-scheme to overcome this problem. Furthermore, a computationally efficient alternative scheme is proposed and evaluated with several examples, to quantify the improvements in the accuracy and the computational time.

Syamlal, Madhava; Benyahia, Sofiane

2013-11-20T23:59:59.000Z

393

Scientific system for high-resolution measurement of the circumsolar radiation  

SciTech Connect (OSTI)

We developed a camera based system for measurements of the circumsolar radiation with a high angular resolution of 0.1 mrad. Subsequent measurements may be taken at intervals as short as 15 s. In this publication we describe the optical system in detail and discuss some aspects of the measurement method. First results from two days of measurement at Freiburg i. Br., Germany, are presented and compared to data from literature. The good results encourage us to perform longer measurement campaigns in future to better understand the influence of circumsolar radiation on the power yield of concentrating photovoltaic systems.

Schrott, Simeon, E-mail: thomas.schmidt@ise.fraunhofer.de; Schmidt, Thomas, E-mail: thomas.schmidt@ise.fraunhofer.de; Hornung, Thorsten, E-mail: thomas.schmidt@ise.fraunhofer.de; Nitz, Peter, E-mail: thomas.schmidt@ise.fraunhofer.de [Fraunhofer Institute for Solar Energy Systems ISE, Freiburg (Germany)

2014-09-26T23:59:59.000Z

394

High-Resolution Infrared and Electron-Diffraction Studies of Trimethylenecyclopropane ([3]-Radialene)  

SciTech Connect (OSTI)

Combined high-resolution spectroscopic, electron-diffraction, and quantum theoretical methods are particularly advantageous for small molecules of high symmetry and can yield accurate structures that reveal subtle effects of electron delocalization on molecular bonds. The smallest of the radialene compounds, trimethylenecyclopropane, [3]-radialene, has been synthesized and examined in the gas phase by these methods. The first high-resolution infrared spectra have been obtained for this molecule of D3h symmetry, leading to an accurate B0 rotational constant value of 0.1378629(8) cm-1, within 0.5% of the value obtained from electronic structure calculations (density functional theory (DFT) B3LYP/cc-pVTZ). This result is employed in an analysis of electron-diffraction data to obtain the rz bond lengths (in Å): C-H = 1.072 (17), C-C = 1.437 (4), and C=C = 1.330 (4). The analysis does not lead to an accurate value of the HCH angle; however, from comparisons of theoretical and experimental angles for similar compounds, the theoretical prediction of 117.5? is believed to be reliable to within 2?. The effect of electron delocalization in radialene is to reduce the single C-C bond length by 0.07 Å compared to that in cyclopropane.

Wright, Corey R.; Holmes, Joshua; Nibler, Joseph W.; Hedberg, Kenneth; White, James D.; Hedberg, Lise; Weber, Alfons; Blake, Thomas A.

2013-05-16T23:59:59.000Z

395

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11LargeLaserLaser Seeding Yields

396

PUBLISHED ONLINE: 17 JANUARY 2010 | DOI: 10.1038/NPHYS1506 High-reflectivity high-resolution X-ray crystal  

E-Print Network [OSTI]

of X-ray free-electron laser oscillators (XFELOs), next-generation hard-X-ray sources of the highest-resolution X-ray crystal optics with diamonds Yuri V. Shvyd'ko1 *, Stanislav Stoupin1 , Alessandro Cunsolo1,2 , Ayman H. Said1 and Xianrong Huang2 Owing to the depth to which hard X-rays penetrate into most materials

Loss, Daniel

397

Large area, high spatial resolution tracker for new generation of high luminosity experiments in Hall A at Jefferson Lab  

SciTech Connect (OSTI)

In 2014 the CEBAF electron accelerator at Jefferson Lab (JLab) will deliver a longitudinally polarized (up to 85%), high intensity (up to 100 ?A) beam with maximum energy of 12 GeV, twice the present value. To exploit the new opportunities that the energy upgrade will offer, a new spectrometer (Super BigBite - SBS) is under development, featuring very forward angle, large acceptance and ability to operate in high luminosity environment. The tracking system of SBS will consist of large area (40×150 cm2 and 50×200 cm2), high spatial resolution (better than 100 ?m) chambers based on the GEM technology and 2 small (10×20 cm) Silicon Strip Detector planes. The design of the GEM chambers and its sub-components such as the readout electronics is resented here.

Bellini, V; Castelluccio, D; Colilli, S; Cisbani, E; De Leo, R; Fratoni, R; Frullani, S; Garibaldi, F; Guiliani, F; Guisa, A; Gricia, M; Lucentini, M; Meddi, F; Minutoli, S; Musico, P; Noto, F; De Oliveira, R; Santavenere, F; Sutera, M C

2011-06-01T23:59:59.000Z

398

Laser-driven hole boring and gamma-ray emission in high-density plasmas  

E-Print Network [OSTI]

Ion acceleration in laser-produced dense plasmas is a key topic of many recent investigations thanks to its potential applications. Besides, at forthcoming laser intensities ($I \\gtrsim 10^{23} \\text{W}\\,\\text{cm}^{-2}$) interaction of laser pulses with plasmas can be accompanied by copious gamma-ray emission. Here we demonstrate the mutual influence of gamma-ray emission and ion acceleration during relativistic hole boring in high-density plasmas with ultra-intense laser pulses. If gamma-ray emission is abundant, laser pulse reflection and hole-boring velocity are lower and gamma-ray radiation pattern is narrower than in the case of low emission. Conservation of energy and momentum allows one to elucidate the effects of gamma-ray emission which are more pronounced at higher hole-boring velocities.

Nerush, Evgeny

2014-01-01T23:59:59.000Z

399

Narrowband inverse Compton scattering x-ray sources at high laser intensities  

E-Print Network [OSTI]

Narrowband x- and gamma-ray sources based on the inverse Compton scattering of laser pulses suffer from a limitation of the allowed laser intensity due to the onset of nonlinear effects that increase their bandwidth. It has been suggested that laser pulses with a suitable frequency modulation could compensate this ponderomotive broadening and reduce the bandwidth of the spectral lines, which would allow to operate narrowband Compton sources in the high-intensity regime. In this paper we, therefore, present the theory of nonlinear Compton scattering in a frequency modulated intense laser pulse. We systematically derive the optimal frequency modulation of the laser pulse from the scattering matrix element of nonlinear Compton scattering, taking into account the electron spin and recoil. We show that, for some particular scattering angle, an optimized frequency modulation completely cancels the ponderomotive broadening for all harmonics of the backscattered light. We also explore how sensitive this compensation ...

Seipt, D; Surzhykov, A; Fritzsche, S

2014-01-01T23:59:59.000Z

400

Spatial Filter with Volume Gratings for High-peak-power Multistage Laser Amplifiers  

E-Print Network [OSTI]

The regular spatial filters comprised of lens and pinhole are essential component in high power laser systems, such as lasers for inertial confinement fusion, nonlinear optical technology and directed-energy weapon. On the other hand the pinhole is treated as a bottleneck of high power laser due to harmful plasma created by the focusing beam. In this paper we present a spatial filter based on angular selectivity of Bragg diffraction grating to avoid the harmful focusing effect in the traditional pinhole filter. A spatial filter consisted of volume phase gratings in two-pass amplifier cavity were reported. Two-dimensional filter was proposed by using single Pi-phase-shifted Bragg grating, numerical simulation results shown that its angular spectrum bandwidth can be less than 160urad. The angular selectivity of photo-thermo-refractive glass and RUGATE film filters, construction stability, thermal stability and the effects of misalignments of gratings on the diffraction efficiencies under high-pulse-energy laser...

Tan, Yi-zhou; Zheng, Guang-wei; Shen, Ben-jian; Pan, Heng-yue; Li, Liu

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

High-resolution shear-wave reflection profiling to image offset in unconsolidated near-surface sediments  

E-Print Network [OSTI]

S-wave reflection profiling has many theoretical advantages, when compared to P-wave profiling, such as high-resolution potential, greater sensitivities to lithologic changes and insensitivity to the water table and pore ...

Bailey, Bevin

2014-05-31T23:59:59.000Z

402

Astron. Nachr./AN 32X (2002) X, XXXXXX Imaging Magnetographs for High-Resolution Solar Observations in  

E-Print Network [OSTI]

Magnetograph (VIM) is basically a twin of IRIM for observations in the wavelength range from 550 nm to 700 nm goals of VIM and IRIM are high temporal and spatial resolution observations while maintaining moderate

403

Fabrication and characterization of a 0.5-mm lutetium oxyorthosilicate detector array for high-resolution PET applications  

E-Print Network [OSTI]

for a high resolution PET detector using position sensitive51:2131–2142. 0.5- MM LSO A RRAY FOR PET • Stickel et al.Instrumentation aspects of animal PET. Annu Rev Biomed Eng.

Stickel, Jennifer R; Qi, Jinyi; Cherry, Simon R

2007-01-01T23:59:59.000Z

404

High-resolution shear-wave reflection profiling to image offset in unconsolidated near-surface sediments.  

E-Print Network [OSTI]

??S-wave reflection profiling has many theoretical advantages, when compared to P-wave profiling, such as high-resolution potential, greater sensitivities to lithologic changes and insensitivity to the… (more)

Bailey, Bevin

2014-01-01T23:59:59.000Z

405

High-resolution calorimetric study of the nematic to smectic- A transition in aligned liquid crystal–aerosil gels  

E-Print Network [OSTI]

High-resolution ac calorimetry has been used to study the nematic to smectic-A (N-SmA) phase transition in the liquid crystal octylcyanobiphenyl (8CB) confined in aligned colloidal aerosil gels. A stable and robust nematic ...

Garland, Carl W.

406

A Curved Image-Plate Detector System for High-Resolution Synchrotron X-ray Diffraction  

SciTech Connect (OSTI)

The developed curved image plate (CIP) is a one-dimensional detector which simultaneously records high-resolution X-ray diffraction (XRD) patterns over a 38.7 2{theta} range. In addition, an on-site reader enables rapid extraction, transfer and storage of X-ray intensity information in {le}30 s, and further qualifies this detector to study kinetic processes in materials science. The CIP detector can detect and store X-ray intensity information linearly proportional to the incident photon flux over a dynamical range of about five orders of magnitude. The linearity and uniformity of the CIP detector response is not compromised in the unsaturated regions of the image plate, regardless of saturation in another region. The speed of XRD data acquisition together with excellent resolution afforded by the CIP detector is unique and opens up wide possibilities in materials research accessible through X-ray diffraction. This article presents details of the basic features, operation and performance of the CIP detector along with some examples of applications, including high-temperature XRD.

Sarin, P.; Haggerty, R; Yoon, W; Knapp, M; Berghaeuser, A; Zschack, P; Karapetrova, E; Yang, N; Kriven, W

2009-01-01T23:59:59.000Z

407

High spatial and temporal resolution charge exchange recombination spectroscopy on the HL-2A tokamak  

SciTech Connect (OSTI)

A 32/64-channel charge exchange recombination spectroscopy (CXRS) diagnostic system is developed on the HL-2A tokamak (R = 1.65 m, a = 0.4 m), monitoring plasma ion temperature and toroidal rotation velocity simultaneously. A high throughput spectrometer (F/2.8) and a pitch-controlled fiber bundle enable the temporal resolution of the system up to 400 Hz. The observation geometry and an optimized optic system enable the highest radial resolution up to ?1 cm at the plasma edge. The CXRS system monitors the carbon line emission (C VI, n = 8–7, 529.06 nm) whose Doppler broadening and Doppler shift provide ion temperature and plasma rotation velocity during the neutral beam injection. The composite CX spectral data are analyzed by the atomic data and analysis structure charge exchange spectroscopy fitting (ADAS CXSFIT) code. First experimental results are shown for the case of HL-2A plasmas with sawtooth oscillations, electron cyclotron resonance heating, and edge transport barrier during the high-confinement mode (H-mode)

Wei, Y. L.; Yu, D. L., E-mail: yudl@swip.ac.cn; Liu, L.; Cao, J. Y.; Sun, A. P.; Ma, Q.; Chen, W. J.; Liu, Yi; Yan, L. W.; Yang, Q. W.; Duan, X. R.; Liu, Yong [Southwestern Institute of Physics, Chengdu 610041 (China); Ida, K. [National Institute for Fusion Science, Toki 509-5292 (Japan); Hellermann, M. von [ITER Diagnostic Team, IO, Route de Vinon sur Verdon, 13115 St Paul lez Durance (France); FOM-Institute for Plasma physics “Rijnhuizen,” Association EURATOM, Trilateral Euregio Cluster, 3430 BE Nieuwegein (Netherlands)

2014-10-15T23:59:59.000Z

408

Random vs realistic amorphous carbon models for high resolution microscopy and electron diffraction  

SciTech Connect (OSTI)

Amorphous carbon and amorphous materials in general are of particular importance for high resolution electron microscopy, either for bulk materials, generally covered with an amorphous layer when prepared by ion milling techniques, or for nanoscale objects deposited on amorphous substrates. In order to quantify the information of the high resolution images at the atomic scale, a structural modeling of the sample is necessary prior to the calculation of the electron wave function propagation. It is thus essential to be able to reproduce the carbon structure as close as possible to the real one. The approach we propose here is to simulate a realistic carbon from an energetic model based on the tight-binding approximation in order to reproduce the important structural properties of amorphous carbon. At first, we compare this carbon with the carbon obtained by randomly generating the carbon atom positions. In both cases, we discuss the limit thickness of the phase object approximation. In a second step, we show the influence of both carbons models on (i) the contrast of Cu, Ag, and Au single atoms deposited on carbon and (ii) the determination of the long-range order parameter in CoPt bimetallic nanoalloys.

Ricolleau, C., E-mail: Christian.Ricolleau@univ-paris-diderot.fr; Alloyeau, D. [Laboratoire Matériaux et Phénomènes Quantiques, CNRS-UMR 7162, Université Paris Diderot-Paris 7, Case 7021, 75205 Paris Cedex 13 (France); Le Bouar, Y.; Amara, H.; Landon-Cardinal, O. [Laboratoire d'Etude des Microstructures, UMR CNRS/Onera, 29, avenue de la Division Leclerc, 92322 Châtillon (France)

2013-12-07T23:59:59.000Z

409

First high-resolution analysis of the 41+3 band of nitrogen dioxide near 1.5 m  

E-Print Network [OSTI]

1 1 First high-resolution analysis of the 41+3 band of nitrogen dioxide near 1.5 µm Agnès Perrin a. Keywords: 14 N16 O2; Nitrogen dioxide; High-resolution infrared spectrum; Electron spin- rotation resonance, CRDS hal-00563141,version1-4Feb2011 #12;3 3 1. Introduction Nitrogen dioxide (14 N16 O2

Boyer, Edmond

410

High Spatial Resolution Fast-Neutron Imaging Detectors for Pulsed Fast-Neutron Transmission Spectroscopy  

E-Print Network [OSTI]

Two generations of a novel detector for high-resolution transmission imaging and spectrometry of fast-neutrons are presented. These devices are based on a hydrogenous fiber scintillator screen and single- or multiple-gated intensified camera systems (ICCD). This detector is designed for energy-selective neutron radiography with nanosecond-pulsed broad-energy (1 - 10 MeV) neutron beams. Utilizing the Time-of-Flight (TOF) method, such a detector is capable of simultaneously capturing several images, each at a different neutron energy (TOF). In addition, a gamma-ray image can also be simultaneously registered, allowing combined neutron/gamma inspection of objects. This permits combining the sensitivity of the fast-neutron resonance method to low-Z elements with that of gamma radiography to high-Z materials.

Mor, I; Bar, D; Feldman, G; Goldberg, M B; Katz, D; Sayag, E; Shmueli, I; Cohen, Y; Tal, A; Vagish, Z; Bromberger, B; Dangendorf, V; Mugai, D; Tittelmeier, K; Weierganz, M

2009-01-01T23:59:59.000Z

411

High resolution interface nanochemistry and structure: Final project report, December 1, 1993--February 28, 1997  

SciTech Connect (OSTI)

Work includes studies of interface and grain boundary chemistry and structure in silicon nitride matrix/silicon carbide whisker composites, and in monolithic silicon nitride and silicon carbide synthesized by several different methods. Off-stoichiometric, impurity, and sintering aid elemental distributions in these materials (and other ceramics) have been of great interest because of expected effects on properties but these distributions have proven very difficult to measure because the spatial resolution required is high. The authors made a number of these measurements for the first time, using techniques and instrumentation developed here. Interfaces between metals and SiC are the basis for important metal matrix composites and contacts for high temperature SiC-based solid state electronic devices. The authors have investigated ultrapure interfaces between Ti, Hf, Ti-Hf alloys, Pt, and Co and Si-terminated (0001) 6H SiC single crystals for the first time.

Carpenter, R.W.; Lin, S.H.

1997-02-27T23:59:59.000Z

412

Study of Fish Response Using Particle Image Velocimetry and High-Speed, High-Resolution Imaging  

SciTech Connect (OSTI)

Existing literature of previous particle image velocimetry (PIV) studies of fish swimming has been reviewed. Historically, most of the studies focused on the performance evaluation of freely swimming fish. Technological advances over the last decade, especially the development of digital particle image velocimetry (DPIV) technique, make possible more accurate, quantitative descriptions of the flow patterns adjacent to the fish and in the wake behind the fins and tail, which are imperative to decode the mechanisms of drag reduction and propulsive efficiency. For flows generated by different organisms, the related scales and flow regimes vary significantly. For small Reynolds numbers, viscosity dominates; for very high Reynolds numbers, inertia dominates, and three-dimensional complexity occurs. The majority of previous investigations dealt with the lower end of Reynolds number range. The fish of our interest, such as rainbow trout and spring and fall chinook salmon, fall into the middle range, in which neither viscosity nor inertia is negligible, and three-dimensionality has yet to dominate. Feasibility tests have proven the applicability of PIV to flows around fish. These tests have shown unsteady vortex shedding in the wake, high vorticity region and high stress region, with the highest in the pectoral area. This evident supports the observations by Nietzel et al. (2000) and Deng et al. (2004) that the operculum are most vulnerable to damage from the turbulent shear flow, because they are easily pried open, and the large vorticity and shear stress can lift and tear off scales, rupture or dislodge eyes, and damage gills. In addition, the unsteady behavior of the vortex shedding in the wake implies that injury to fish by the instantaneous flow structures would likely be much higher than the injury level estimated using the average values of the dynamics parameters. Based on existing literature, our technological capability, and relevance and practicability to Department of Energy's Hydropower Program, we identified three major research areas of interest: free swimming, the boundary layer over fish, and kinematic response of fish. We propose that the highest priority is to characterize the kinematic response of fish to different turbulent environments such as high shear/turbulence and hydrodynamic disturbances created by solid structures such as deflector and turbine runner blade; the next priority is to map the boundary layer over swimming fish; the last is to document the behavior of freely swimming fish, focusing on fish of our interest. Grid turbulence and Karman vortex street will be employed to map the boundary layers over fish and investigate the effects of environmental disturbances on the swimming performance of fish, because they are well established and documented in engineering literature and are representative of fish's swimming environments. Extreme conditions characteristic of turbine environments, such as strong shear environment and collision, will be investigated. Through controlled laboratory studies, the fish injury mechanism from different sources will be evaluated in isolation. The major goals are to: gain first-hand knowledge of the biological effects under such extreme hydraulic environments in which fish could lack the capability to overcome the perturbations and be vulnerable to injury; Better understand field results by integrating the laboratory studies with the responses of sensor fish device; More importantly, provide well-defined validation cases and boundary conditions for geometry-based computational fluid-structure interaction modeling in order to simulate the complex hydraulic environments in advanced hydropower systems and their effects on fish, greatly enhancing the potential to use CFD as a bio-hydraulic design alternative.

Deng, Zhiqun; Richmond, Marshall C.; Guensch, Gregory R.; Mueller, Robert P.

2004-10-23T23:59:59.000Z

413

SIEMENS ADVANCED QUANTRA FTICR MASS SPECTROMETER FOR ULTRA HIGH RESOLUTION AT LOW MASS  

SciTech Connect (OSTI)

The Siemens Advanced Quantra Fourier Transform Ion Cyclotron Resonance (FTICR) mass spectrometer was evaluated as an alternative instrument to large double focusing mass spectrometers for gas analysis. High resolution mass spectrometers capable of resolving the common mass isomers of the hydrogen isotopes are used to provide data for accurate loading of reservoirs and to monitor separation of tritium, deuterium, and helium. Conventional double focusing magnetic sector instruments have a resolution that is limited to about 5000. The Siemens FTICR instrument achieves resolution beyond 400,000 and could possibly resolve the tritium ion from the helium-3 ion, which differ by the weight of an electron, 0.00549 amu. Working with Y-12 and LANL, SRNL requested Siemens to modify their commercial Quantra system for low mass analysis. To achieve the required performance, Siemens had to increase the available waveform operating frequency from 5 MHz to 40 MHz and completely redesign the control electronics and software. However, they were able to use the previous ion trap, magnet, passive pump, and piezo-electric pulsed inlet valve design. NNSA invested $1M in this project and acquired four systems, two for Y-12 and one each for SRNL and LANL. Siemens claimed a $10M investment in the Quantra systems. The new Siemens Advanced Quantra demonstrated phenomenal resolution in the low mass range. Resolution greater than 400,000 was achieved for mass 2. The new spectrometer had a useful working mass range to 500 Daltons. However, experiments found that a continuous single scan from low mass to high was not possible. Two useful working ranges were established covering masses 1 to 6 and masses 12 to 500 for our studies. A compromise performance condition enabled masses 1 to 45 to be surveyed. The instrument was found to have a dynamic range of about three orders of magnitude and quantitative analysis is expected to be limited to around 5 percent without using complex fitting algorithms. Analysis of low concentration ions, at the ppm level, required a separate analysis using ion ejection techniques. Chemical ionization due to the formation of the MH{sup +} ion or MD{sup +} increased the complexity of the spectra compared to magnetic sector mass spectra and formation of the protonated or deuterated complex was a dynamic function of the trap ion concentration. This made quantitative measurement more of a challenge. However, the resolution of the instrument was far superior to any other mass spectrometry technique that has been applied to the analysis of the hydrogen isotopes. The piezo-electric picoliter injection device offers a new way of submitting small quantities of atmospheric pressure sample gas for analysis. The new software had many improvements over the previous version but significant flaws in the beta codes remain that make the prototype units less than ideal. The instrument is a promising new technology that experience will likely improve. Unfortunately, Siemens has concluded that the technology will not be a commercial success and has decided to stop producing this product.

Spencer, W; Laura Tovo, L

2008-07-08T23:59:59.000Z

414

Speckle-free laser imaging  

E-Print Network [OSTI]

Many imaging applications require increasingly bright illumination sources, motivating the replacement of conventional thermal light sources with light emitting diodes (LEDs), superluminescent diodes (SLDs) and lasers. Despite their brightness, lasers and SLDs are poorly suited for full-field imaging applications because their high spatial coherence leads to coherent artifacts known as speckle that corrupt image formation. We recently demonstrated that random lasers can be engineered to provide low spatial coherence. Here, we exploit the low spatial coherence of specifically-designed random lasers to perform speckle-free full-field imaging in the setting of significant optical scattering. We quantitatively demonstrate that images generated with random laser illumination exhibit higher resolution than images generated with spatially coherent illumination. By providing intense laser illumination without the drawback of coherent artifacts, random lasers are well suited for a host of full-field imaging applicatio...

Redding, Brandon; Cao, Hui

2011-01-01T23:59:59.000Z

415

Animals In Synchrotrons: Overcoming Challenges For High-Resolution, Live, Small-Animal Imaging  

SciTech Connect (OSTI)

Physiological studies in small animals can be complicated, but the complexity is increased dramatically when performing live-animal synchrotron X-ray imaging studies. Our group has extensive experience in high-resolution live-animal imaging at the Japanese SPring-8 synchrotron, primarily examining airways in two-dimensions. These experiments normally image an area of 1.8 mmx1.2 mm at a pixel resolution of 0.45 {mu}m and are performed with live, intact, anaesthetized mice.There are unique challenges in this experimental setting. Importantly, experiments must be performed in an isolated imaging hutch not specifically designed for small-animal imaging. This requires equipment adapted to remotely monitor animals, maintain their anesthesia, and deliver test substances while collecting images. The horizontal synchrotron X-ray beam has a fixed location and orientation that limits experimental flexibility. The extremely high resolution makes locating anatomical regions-of-interest slow and can result in a high radiation dose, and at this level of magnification small animal movements produce motion-artifacts that can render acquired images unusable. Here we describe our experimental techniques and how we have overcome several challenges involved in performing live mouse synchrotron imaging.Experiments have tested different mouse strains, with hairless strains minimizing overlying skin and hair artifacts. Different anesthetics have also be trialed due to the limited choices available at SPring-8. Tracheal-intubation methods have been refined and controlled-ventilation is now possible using a specialized small-animal ventilator. With appropriate animal restraint and respiratory-gating, motion-artifacts have been minimized. The animal orientation (supine vs. head-high) also appears to affect animal physiology, and can alter image quality. Our techniques and image quality at SPring-8 have dramatically improved and in the near future we plan to translate this experience to the Imaging and Medical Beamline at the Australian Synchrotron.Overcoming these challenges has permitted increasingly sophisticated imaging of animals with synchrotron X-rays, and we expect a bright future for these techniques.

Donnelley, Martin [Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, South Australia (Australia); Parsons, David [Respiratory and Sleep Medicine, Women's and Children's Hospital, Adelaide, South Australia (Australia); Women's and Children's Health Research Institute, Adelaide, South Australia (Australia); Department of Paediatrics and Reproductive Health, University of Adelaide, South Australia (Australia); Department of Paediatircs Centre for Stem Cell Research, University of Adelaide, South Australia (Australia); Morgan, Kaye [School of Physics, Monash University, Melbourne, Victoria (Australia); Siu, Karen [School of Physics, Monash University, Melbourne, Victoria (Australia); Monash Centre for Synchrotron Science, Monash University, Melbourne, Victoria (Australia)

2010-07-23T23:59:59.000Z

416

High resolution fossil fuel combustion CO2 emission fluxes for the United States  

SciTech Connect (OSTI)

Quantification of fossil fuel CO{sub 2} emissions at fine space and time resolution is emerging as a critical need in carbon cycle and climate change research. As atmospheric CO{sub 2} measurements expand with the advent of a dedicated remote sensing platform and denser in situ measurements, the ability to close the carbon budget at spatial scales of {approx}100 km{sup 2} and daily time scales requires fossil fuel CO{sub 2} inventories at commensurate resolution. Additionally, the growing interest in U.S. climate change policy measures are best served by emissions that are tied to the driving processes in space and time. Here we introduce a high resolution data product (the 'Vulcan' inventory: www.purdue.edu/eas/carbon/vulcan/) that has quantified fossil fuel CO{sub 2} emissions for the contiguous U.S. at spatial scales less than 100 km{sup 2} and temporal scales as small as hours. This data product, completed for the year 2002, includes detail on combustion technology and 48 fuel types through all sectors of the U.S. economy. The Vulcan inventory is built from the decades of local/regional air pollution monitoring and complements these data with census, traffic, and digital road data sets. The Vulcan inventory shows excellent agreement with national-level Department of Energy inventories, despite the different approach taken by the DOE to quantify U.S. fossil fuel CO{sub 2} emissions. Comparison to the global 1{sup o} x 1{sup o} fossil fuel CO{sub 2} inventory, used widely by the carbon cycle and climate change community prior to the construction of the Vulcan inventory, highlights the space/time biases inherent in the population-based approach.

Gurney, Kevin R.; Mendoza, Daniel L.; Zhou, Yuyu; Fischer, Marc L.; Miller, Chris C.; Geethakumar, Sarath; de la Rue du Can, Stephane

2009-03-19T23:59:59.000Z

417

Generation of high-energy-density ion bunches by ultraintense laser-cone-target interaction  

SciTech Connect (OSTI)

A scheme in which carbon ion bunches are accelerated to a high energy and density by a laser pulse (?10{sup 21}?W/cm{sup 2}) irradiating cone targets is proposed and investigated using particle-in-cell simulations. The laser pulse is focused by the cone and drives forward an ultrathin foil located at the cone's tip. In the course of the work, best results were obtained employing target configurations combining a low-Z cone with a multispecies foil transversely shaped to match the laser intensity profile.

Yang, X. H.; Zhuo, H. B., E-mail: hongbin.zhuo@gmail.com; Ma, Y. Y.; Zou, D. B.; Yu, T. P.; Ge, Z. Y.; Yin, Y.; Shao, F. Q. [College of Science, National University of Defense Technology, Changsha 410073 (China); Yu, W. [Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800 (China); Xu, H., E-mail: xuhanemail@gmail.com [State Key Laboratory of High Performance Computing, National University of Defense Technology, Changsha 410073 (China); Borghesi, M., E-mail: m.borghesi@qub.ac.uk [School of Mathematics and Physics, Queen's University of Belfast, Belfast BT7 1NN (United Kingdom); Institute of Physics of the ASCR, ELI-Beamlines Project, Na Slovance 2, 18221 Prague (Czech Republic)

2014-06-15T23:59:59.000Z

418

Laser synchronized high-speed shutter for spectroscopic application  

DOE Patents [OSTI]

A fast mechanical shutter, based on rotating chopper wheels, has been designed and implemented to shutter the entrance slit of a spectrograph. This device enables an exposure time of 9 .mu.s to be achieved for a 0.8 mm wide spectrograph entrance slit, achieves 100% transmission in the open state, and an essentially infinite extinction ratio. The device further incorporates chopper wheel position sensing electronics to permit the synchronous triggering of a laser source.

Miles, Paul C. (Tracy, CA); Porter, Eldon L. (Tracy, CA); Prast, Thomas L. (Livermore, CA); Sunnarborg, Duane A. (Livermore, CA)

2002-01-01T23:59:59.000Z

419

High temperature thermographic measurements of laser heated silica  

SciTech Connect (OSTI)

In situ spatial and temporal surface temperature profiles of CO{sub 2} laser-heated silica were obtained using a long wave infrared (LWIR) HgCdTe camera. Solutions to the linear diffusion equation with volumetric and surface heating are shown to describe the temperature evolution for a range of beam powers, over which the peak surface temperature scales linearly with power. These solutions were used with on-axis steady state and transient experimental temperatures to extract thermal diffusivity and conductivity for a variety of materials, including silica, spinel, sapphire, and lithium fluoride. Experimentally-derived thermal properties agreed well with reported values and, for silica, thermal conductivity and diffusivity are shown to be approximately independent of temperature between 300 and 2800K. While for silica our analysis based on a temperature independent thermal conductivity is shown to be accurate, for other materials studied this treatment yields effective thermal properties that represent reasonable approximations for laser heating. Implementation of a single-wavelength radiation measurement in the semi-transparent regime is generally discussed, and estimates of the apparent temperature deviation from the actual outer surface temperature are also presented. The experimental approach and the simple analysis presented yield surface temperature measurements that can be used to validate more complex physical models, help discriminate dominant heat transport mechanisms, and to predict temperature distribution and evolution during laser-based material processing.

Elhadj, S; Yang, S T; Matthews, M J; Cooke, D J; Bude, J D; Johnson, M; Feit, M; Draggoo, V; Bisson, S E

2009-11-02T23:59:59.000Z

420

Submillimeter Array High-angular Resolution Observations of the Monoceros R2 Star Forming Cluster  

E-Print Network [OSTI]

We present the first high-angular resolution study of the MonR2 star-forming complex carried out with the Submillimeter Array at (sub-)millimeter wavelengths. We image the continuum and molecular line emission toward the young stellar objects in MonR2 at 0.85mm and 1.3mm, with resolutions ranging from 0.5" to ~3". While free-free emission dominates the IRS1 and IRS2 continuum, dust thermal emission prevails for IRS3 and IRS5, giving envelope masses of ~0.1-0.3 M_Sun. IRS5 splits into at least two sub-arcsecond scale sources, IRS5B and the more massive IRS5A. Our 12CO(2-1) images reveal 11 previously unknown molecular outflows in the MonR2 clump. Comparing these outflows with known IR sources in the IRS5 and IRS3 subclusters allows for tentative identification of driving stars. Line images of molecular species such as CH3CN or CH3OH show that, besides IRS3 (a well-known hot molecular core), IRS5 is also a chemically active source in the region. The gas excitation temperature derived from CH3CN lines toward IRS...

Dierickx, Marion; Rivilla, Victor; Zhang, Qizhou

2015-01-01T23:59:59.000Z

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421

High-resolution spectra of solar magnetic features. I. Analysis of penumbral fine structure  

SciTech Connect (OSTI)

The Swedish Vacuum Telescope on La Palma was used to obtain spectra of the magnetic-sensitive Fe I 630.25 nm line under conditions of exceptional angular resolution (0.32 arcsec) and high spectral resolution (FWHM 2.5 pm). Simultaneous 0.02 s CCD exposures of both the spectrum and the slit-jaw image effectively 'freeze' the atmospheric seeing motions and permit unambiguous identification of the spectra of the various penumbral structures. These spectra reveal the magnetic field strength in penumbral filaments through an intensity fit of the Zeeman splitting of this line. The observations show that: (1) the field strength varies from about 2100 G near the umbra-penumbra boundary to about 900 G at the outer edge of the penumbra, (2) the observed fluctuation of penumbral magnetic field is much less dramatic than the fluctuation in intensity, (3) there is a suggestion of a rapid change in field inclination between some light and dark filaments near the edge of the penumbra, and (4) there is no obvious correlation between Doppler shift (in part due to the Evershed flow) and filament intensity. 43 refs.

Lites, B.W.; Skumanich, A.; Scharmer, G.B. (High Altitude Observatory, Boulder, CO (USA) Kungliga Svenska Vetenskapsakademien, Stockholm (Sweden))

1990-05-01T23:59:59.000Z

422

High-resolution observations of active region moss and its dynamics  

E-Print Network [OSTI]

The \\textit{High resolution Coronal Imager (Hi-C)} has provided the sharpest view of the EUV corona to date. In this paper we exploit its impressive resolving power to provide the first analysis of the fine-scale structure of moss in an active region. The data reveal that the moss is made up of a collection of fine threads, that have widths with a mean and standard deviation of $440\\pm190$~km (Full Width Half Maximum). {The brightest moss emission is located at the visible head of the fine-scale structure and the fine structure appears to extend into the lower solar atmosphere.} The emission decreases along the features implying the lower sections are most likely dominated by cooler transition region plasma. These threads appear to be the cool, lower legs of the hot loops. In addition, the increased resolution allows for the first direct observation {of physical displacements of the moss fine-structure in a direction transverse to its central axis. Some of these transverse displacements demonstrate periodic b...

Morton, R J

2014-01-01T23:59:59.000Z

423

High resolution transmission electron microscopy of melamine-formaldehyde aerogels and silica aerogels  

SciTech Connect (OSTI)

The goal of the high resolution transmission electron microscopy (HRTEM) was to image the structure of two tetramethyl orthosilicate (TMOS) and two melamine-formaldehyde (MF) aerogels at the single polymer chain level{sup 1,2}. With this level of structural resolution we hoped to interrelate each aerogel's structure with its physical properties and its method of synthesis. Conventional single-step base catalysed TMOS aerogels show strings of spheroidal particles linked together with minimal necking. The spheroidal particles range from 86--132 {Angstrom} and average 113{plus minus}10 {Angstrom} in diameter{sup 2}. In contrast the TMOS aerogels reported on here were made by a two step method. After extended silica chains are grown in solution under acidic conditions with a substoichiometric amount of water, the reaction is stopped and the methanol hydrolysed from TMOS is removed. Then base catalysis and additional water are added to cause gel formation is a nonalcoholic solvent. The MF aerogels were prepared for HRTEM by fracturing them on a stereo microscope stage with razor knife so that fractured pieces with smooth flat surfaces could be selected for platinum-carbon replication. The two silica (TMOS) aerogels were both transparent and difficult to see. These aerogels were fractured on a stereo microscope stage with tweezers. 6 refs., 4 figs.

Ruben, G.C. (Dartmouth Coll., Hanover, NH (United States). Dept. of Biological Sciences)

1991-09-01T23:59:59.000Z

424

Impedance-matching experiments using high-pressure, laser-driven shock waves  

SciTech Connect (OSTI)

A high-power laser was used to produce shock waves with pressures of 300 to 700 GPa. A series of impedance-matching experiments on aluminum-copper systems with 10% accuracy indicate several areas in which the experiment can be improved to reduce the errors. Several such improvements are now being made, including upgrading both the laser and recording systems and modifying the target characterization techniques.

Veeser, L.R.; Reeves, G.A.; Holmes, N.C.; Trainor, R.J.; Anderson, R.A.

1981-01-01T23:59:59.000Z

425

Development of a frequency doubled high powered laser diode end-pumped Nd:YVO?/LBO laser  

E-Print Network [OSTI]

to determine the temperature distribution within the laser media. Experiments are performed to characterize the laser diode spectral output and laser crystal response to the pump radiation. Finally, the thesis presents a simple technique to image infrared...

Barr, Aaron Maxwell

2012-06-07T23:59:59.000Z

426

Dynamical Schwinger effect and high-intensity lasers. Realising nonperturbative QED  

E-Print Network [OSTI]

We consider the possibility of experimental verification of vacuum e^+e^- pair creation at the focus of two counter-propagating optical laser beams with intensities 10^{20}-10^{22} W/cm^2, achievable with present-day petawatt lasers, and approaching the Schwinger limit: 10^{29} W/cm^2 to be reached at ELI. Our approach is based on the collisionless kinetic equation for the evolution of the e^+ and e^- distribution functions governed by a non-Markovian source term for pair production. As possible experimental signals of vacuum pair production we consider e^+e^- annihilation into gamma-pairs and the refraction of a high-frequency probe laser beam by the produced e^+e^- plasma. We discuss the dependence of the dynamical pair production process on laser wavelength, with special emphasis on applications in the X-ray domain (X-FEL), as well as the prospects for \\mu^+\\mu^- and \\pi^+\\pi^- pair creation at high-intensity lasers. We investigate perspectives for using high-intensity lasers as ``boosters'' of ion beams in the few-GeV per nucleon range, which is relevant, e.g., to the exploration of the QCD phase transition in laboratory experiments.

D. B. Blaschke; A. V. Prozorkevich; G. Roepke; C. D. Roberts; S. M. Schmidt; D. S. Shkirmanov; S. A. Smolyansky

2008-11-21T23:59:59.000Z

427

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double pulses  

E-Print Network [OSTI]

Enhancement of x-ray line emission from plasmas produced by short high-intensity laser double laser-produced plasmas are bright ultrafast line x-ray sources potentially suitable for different onto a solid target into the x-ray emission is significantly enhanced when a laser prepulse precedes

Limpouch, Jiri

428

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses  

E-Print Network [OSTI]

Line X-ray emission from Al targets irradiated by high-intensity, variable-length laser pulses J; the scaling rules for the conversion efficiency of the laser radiation into the line X-ray emission are discussed. Keywords: Laser-produced plasma; Line X-ray emission; X-ray sources; X-ray spectroscopy 1

Limpouch, Jiri

429

Accurate Gravities of F, G, and K stars from High Resolution Spectra Without External Constraints  

E-Print Network [OSTI]

We demonstrate a new procedure to derive accurate and precise surface gravities from high resolution spectra without the use of external constraints. Our analysis utilizes Spectroscopy Made Easy (SME) with robust spectral line constraints and uses an iterative process to mitigate degeneracies in the fitting process. We adopt an updated radiative transfer code, a new treatment for neutral perturber broadening, a line list with multiple gravity constraints and separate fitting for global stellar properties and abundance determinations. To investigate the sources of temperature dependent trends in determining log g noted in previous studies, we obtained Keck HIRES spectra of 42 Kepler asteroseismic stars. In comparison to asteroseismically determined log g our spectroscopic analysis has a constant offset of 0.01 dex with a root mean square (RMS) scatter of 0.05 dex. We also analyzed 30 spectra which had published surface gravities determined using the $a/R_*$ technique from planetary transits and found a constan...

Brewer, John M; Basu, Sarbani; Valenti, Jeff A; Piskunov, Nikolai

2015-01-01T23:59:59.000Z

430

Plasma Diagnostics in High-Resolution X-ray Spectra of Magnetic Cataclysmic Variables  

E-Print Network [OSTI]

Using the Chandra HETG spectrum of EX Hya as an example, we discuss some of the plasma diagnostics available in high-resolution X-ray spectra of magnetic cataclysmic variables. Specifically, for conditions appropriate to collisional ionization equilibrium plasmas, we discuss the temperature dependence of the H- to He-like line intensity ratios and the density and photoexcitation dependence of the He-like R line ratios and the Fe XVII I(17.10 A)/I(17.05 A) line ratio. We show that the plasma temperature in EX Hya spans the range from ~ 0.5 to ~ 10 keV and that the plasma density n > 2E14 cm^{-3}, orders of magnitude greater than that observed in the Sun or other late-type stars.

Christopher W. Mauche

2001-10-09T23:59:59.000Z

431

Recent results on high resolution hypernuclear spectroscopy by electroproduction at Jefferson Lab, Hall A  

SciTech Connect (OSTI)

The first ''systematic'' study of 1 p shell hypernuclei with electromagnetic probes has started in Hall A at Jefferson Lab [?]. The aim is to perform hypernuclear high resolution spectroscopy by the electroproduction of strangeness on four 1p-shell targets: 12C, 9Be, 16O, 7Li. The first part of the experiment on 12C and 9Be has been performed in 2004, the second part (16O and 7Li) is scheduled for June 2005. To overcome the major experimental difficulties, namely the low counting rate and the challenging Particle IDentification (PID), two septum magnets and a Ring Imaging CHerenkov (RICH) detector had to be added to the existing apparatus. After underlining the particular role the electroproduction reaction plays in hypernuclear physics we describe the challenging modifications of the Hall A apparatus. Preliminary results on 12C and 9Be are presented.

F. Garibaldi; H. Breuer; P. Brindza; P. Bydzovski; G. Chang; E. Cisbani; S. Colilli; F. Cusanno; R. De Leo; G. De Cataldo; K. De Jager; R. Feuerbach; E. Folts; R. Fratoni; S. Frullani; F. Giuliani; M. Gricia; D. Higinbotham; M. Iodice; B. Kross; L. Lagamba; J.J.Le Rose; M. Lucentini; P. Markowitz; S. Marrone; R. Michaels; E. Nappi; Y. Qiang; B. Reitz; F. Santavenere; J. Segal; M. Sotona; G.M.Urciuoli; P. Veneroni; B.Wojtsekhowski; C. Zorn

2005-12-01T23:59:59.000Z

432

Optical multichannel analyzer-based high-resolution, multipoint spectroscopic apparatus  

SciTech Connect (OSTI)

A high-wavelength resolution (..delta..lambdaless than or equal to0.02 A) spectroscopic apparatus has been developed and applied to the measurements of spectral line profiles emitted by thermonuclear plasmas yielding important plasma parameters, such as ion temperature and fluid velocity. The experimental apparatus consists of a spectrometer, an optical multichannel analyzer (OMA), and a lens. It allows precise wavelength measurements (..delta..lambda/sub error/less than or equal to0.02 A) when a computer and a ThI electrodeless discharge lamp (EDL) are used to calibrate the instrument. The apparatus yields single-shot space and time-resolved spectra for radiation in the 2000--8000-A range.

Antoniades, J.A.; Peyser, T.

1987-02-01T23:59:59.000Z

433

High resolution structure of the large ribosomal subunit from a Mesophilic Eubacterium  

SciTech Connect (OSTI)

We describe the high resolution structure of the large ribosomal subunit from Deinococcus radiodurans (D50S), a gram-positive mesophile suitable for binding of antibiotics and functionally relevant ligands. The over-all structure of D50S is similar to that from the archae bacterium Haloarcula marismortui (H50S); however, a detailed comparison revealed significant differences, for example, in the orientation of nucleotides in peptidyl transferase center and in the structures of many ribosomal proteins. Analysis of ribosomal features involved in dynamic aspects of protein biosynthesis that are partially or fully disordered in H50S revealed the conformations of intersubunit bridges in unbound subunits, suggesting how they may change upon subunit association and how movements of the L1-stalk may facilitate the exit of tRNA.

Harms, Joerg; Schluenzen, Frank; Zarivach, Raz; Bashan, Anat; Gat, Sharon; Agmon, Ilana; Bartels, Heike; Franceschi, Francois; Yonath, Ada (Weizmann Inst Israel); (Mac Planck Germany); (Max Planck Germany)

2009-10-07T23:59:59.000Z

434

Solar wind turbulence from MHD to sub-ion scales: high-resolution hybrid simulations  

E-Print Network [OSTI]

We present results from a high-resolution and large-scale hybrid (fluid electrons and particle-in-cell protons) two-dimensional numerical simulation of decaying turbulence. Two distinct spectral regions (separated by a smooth break at proton scales) develop with clear power-law scaling, each one occupying about a decade in wave numbers. The simulation results exhibit simultaneously several properties of the observed solar wind fluctuations: spectral indices of the magnetic, kinetic, and residual energy spectra in the magneto-hydrodynamic (MHD) inertial range along with a flattening of the electric field spectrum, an increase in magnetic compressibility, and a strong coupling of the cascade with the density and the parallel component of the magnetic fluctuations at sub-proton scales. Our findings support the interpretation that in the solar wind large-scale MHD fluctuations naturally evolve beyond proton scales into a turbulent regime that is governed by the generalized Ohm's law.

Franci, Luca; Matteini, Lorenzo; Landi, Simone; Hellinger, Petr

2015-01-01T23:59:59.000Z

435

Air Fluorescence Calorimetry with the High Resolution Fly's Eye and Telescope Array Experiments  

SciTech Connect (OSTI)

The air fluorescence technique was first successfully deployed on the Fly's Eye Experiment (1981-1993) by the University of Utah. Its successor, the High Resolution Fly's Eye (HiRes) experiment has further exploited this technique, first in hybrid mode with the MIA muon array (1993-1996), and then in monocular and stereoscopic modes (1997-2006). Results from HiRes will be presented, including evidence for the Greisen-Zatsepin-K'uzmin (GZK) Effect predicted 40 years ago. Most recently, members of the HiRes are collaborating with groups from Japan, led by University of Tokyo, to construct and operate the Telescope Array (TA) experiment, which will deploy a large scintillation-based ground array in combination with fluorescence detectors. Funding for TA in the US has already been approved by NSF. TA will begin operation in 2007.

Jui, Charles C. H. [Department of Physics, University of Utah Salt Lake City, Utah (United States)

2006-10-27T23:59:59.000Z

436

Deflection Measurements of a Thermally Simulated Nuclear Core using a High-Resolution CCD-Camera  

SciTech Connect (OSTI)

Space fission systems under consideration for near-term missions all use compact, fast-spectrum reactor cores. Reactor dimensional change with increasing temperature, which affects neutron leakage, is the dominant source of reactivity feedback in these systems. Accurately measuring core dimensional changes during realistic non-nuclear testing is therefore necessary in predicting the system 'nuclear' equivalent behavior. This paper discusses one key technique being evaluated for measuring such changes. The proposed technique is to use a Charged Couple Device (CCD) sensor to obtain deformation readings of electrically heated prototypic reactor core geometry. This paper introduces a technique by which a single high spatial resolution CCD camera is used to measure core deformation in Real-Time (RT). Initial system checkout results are presented along with a discussion on how additional cameras could be used to achieve a three-dimensional deformation profile of the core during test. (authors)

Stanojev, B.J. [Marshall Space Flight Center, National Aeronautics and Space Administration, Huntsville, Al, 35812 (United States); Houts, M. [Los Alamos National Laboratory, Department of Energy, Los Alamos, NM, 87545 (United States)

2004-07-01T23:59:59.000Z

437

A High-Resolution Aeromagnetic Survey to Identify Buried Faults at Dixie Valley, Nevada  

SciTech Connect (OSTI)

Preliminary results from a high-resolution aeromagnetic survey (200m line spacing) acquired in Dixie Valley early in 2002 provide confirmation of intra-basin faulting based on subtle surface indications. In addition the data allow identification of the locations and trends of many faults that have not been recognized at the surface, and provide a picture of intrabasin faulting patterns not possible using other techniques. The data reveal a suite of northeasterly-trending curving and branching faults that surround a relatively coherent block in the area of Humboldt Salt Marsh, the deepest part of the basin. The producing reservoir occurs at the north end of this coherent block, where rampart faults from the northwest side of the valley merge with anthithetic faults from the central and southeast parts of the valley.

Smith, Richard Paul; Grauch, V. J. S.; Blackwell, David D.

2002-09-01T23:59:59.000Z

438

High-Resolution Fast-Neutron Spectrometry for Arms Control and Treaty Verification  

SciTech Connect (OSTI)

Many nondestructive nuclear analysis techniques have been developed to support the measurement needs of arms control and treaty verification, including gross photon and neutron counting, low- and high-resolution gamma spectrometry, time-correlated neutron measurements, and photon and neutron imaging. One notable measurement technique that has not been extensively studied to date for these applications is high-resolution fast-neutron spectrometry (HRFNS). Applied for arms control and treaty verification, HRFNS has the potential to serve as a complimentary measurement approach to these other techniques by providing a means to either qualitatively or quantitatively determine the composition and thickness of non-nuclear materials surrounding neutron-emitting materials. The technique uses the normally-occurring neutrons present in arms control and treaty verification objects of interest as an internal source of neutrons for performing active-interrogation transmission measurements. Most low-Z nuclei of interest for arms control and treaty verification, including 9Be, 12C, 14N, and 16O, possess fast-neutron resonance features in their absorption cross sections in the 0.5- to 5-MeV energy range. Measuring the selective removal of source neutrons over this energy range, assuming for example a fission-spectrum starting distribution, may be used to estimate the stoichiometric composition of intervening materials between the neutron source and detector. At a simpler level, determination of the emitted fast-neutron spectrum may be used for fingerprinting 'known' assemblies for later use in template-matching tests. As with photon spectrometry, automated analysis of fast-neutron spectra may be performed to support decision making and reporting systems protected behind information barriers. This paper will report recent work at Idaho National Laboratory to explore the feasibility of using HRFNS for arms control and treaty verification applications, including simulations and experiments, using fission-spectrum neutron sources to assess neutron transmission through composite low-Z attenuators.

David L. Chichester; James T. Johnson; Edward H. Seabury

2012-07-01T23:59:59.000Z

439

Investigation of the Behavior of Ethylene Molecular Films Using High Resolution Adsorp  

SciTech Connect (OSTI)

The wetting behavior of ethylene adsorbed on MgO(100) was investigated from 83-135 K using high resolution volumetric adsorption isotherms. The results are compared to ethylene adsorption on graphite, a prototype adsorption system, in an effort to gain further insight into the forces that drive the observed film growth. Layering transitions for ethylene on MgO(100) are observed below the bulk triple point of ethylene (T=104.0 K). The formation of three discrete adlayers is observed on the MgO(100) surface; onset of the second and third layers occurs at 79.2 ( 1.3 K and 98.3(0.9 K, respectively. Thermodynamic quantities such as differential enthalpy and entropy, heat of adsorption, and isosteric heat of adsorption are determined and compared to the previously published values for ethylene on graphite. The average area occupied by a ethylene molecule on MgO(100) is 22.6 ( 1.1A 2 molecule-1. The locations of two phase transitions are identified (i.e., layer critical temperatures at Tc2 (n=1) at 108.6 ( 1.7 K and Tc2 (n=2) at 116.5 ( 1.2 K) and a phase diagram is proposed. Preliminary neutron diffraction measurements reveal evidence of a monolayer solid with a lattice constant of 4.2A . High resolution INS measurements show that the onset to dynamical motion and monolayer melting take place at 35 K and 65 K, respectively. The data reported here exhibit a striking similarity to ethylene on graphite which suggests that molecule-molecule interactions play an important role in determining the physical properties and growth of molecularly thin ethylene films.

Barbour, Andi M [ORNL; Telling, Mark T. [ISIS Facility, Rutherford Appleton Laboratory; Larese, John Z [ORNL

2010-01-01T23:59:59.000Z

440

COMPLEX ORGANIC MOLECULES AT HIGH SPATIAL RESOLUTION TOWARD ORION-KL. I. SPATIAL SCALES  

SciTech Connect (OSTI)

Here we present high spatial resolution (<1'') observations of molecular emission in Orion-KL conducted using the Combined Array for Research in Millimeter-wave Astronomy. This work was motivated by recent millimeter continuum imaging studies of this region conducted at a similarly high spatial resolution, which revealed that the bulk of the emission arises from numerous compact sources, rather than the larger-scale extended structures typically associated with the Orion Hot Core and Compact Ridge. Given that the spatial extent of molecular emission greatly affects the determination of molecular abundances, it is important to determine the true spatial scale for complex molecules in this region. Additionally, it has recently been suggested that the relative spatial distributions of complex molecules in a source might give insight into the chemical mechanisms that drive complex chemistry in star-forming regions. In order to begin to address these issues, this study seeks to determine the spatial distributions of ethyl cyanide [C{sub 2}H{sub 5}CN], dimethyl ether [(CH{sub 3}){sub 2}O], methyl formate [HCOOCH{sub 3}], formic acid [HCOOH], acetone [(CH{sub 3}){sub 2}CO], SiO, methanol [CH{sub 3}OH], and methyl cyanide [CH{sub 3}CN] in Orion-KL at {lambda} = 3 mm. We find that for all observed molecules, the molecular emission arises from multiple components of the cloud that include a range of spatial scales and physical conditions. Here, we present the results of these observations and discuss the implications for studies of complex molecules in star-forming regions.

Widicus Weaver, Susanna L. [Department of Chemistry, Emory University, Atlanta, GA 30322 (United States); Friedel, Douglas N., E-mail: susanna.widicus.weaver@emory.edu, E-mail: friedel@astro.illinois.edu [Department of Astronomy, University of Illinois, 1002 West Green Street, Urbana, IL 61801 (United States)

2012-08-01T23:59:59.000Z

Note: This page contains sample records for the topic "high resolution laser" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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441

Laser Seeding Yields High-Power Coherent Terahertz Radiation  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11LargeLaser

442

High resolution analysis of soil elements with laser-induced breakdown  

DOE Patents [OSTI]

The invention is a system and method of detecting a concentration of an element in a soil sample wherein an opening or slot is formed in a container that supports a soil sample that was extracted from the ground whereupon at least a length of the soil sample is exposed via the opening. At each of a plurality of points along the exposed length thereof, the soil sample is ablated whereupon a plasma is formed that emits light characteristic of the elemental composition of the ablated soil sample. Each instance of emitted light is separated according to its wavelength and for at least one of the wavelengths a corresponding data value related to the intensity of the light is determined. As a function of each data value a concentration of an element at the corresponding point along the length of the soil core sample is determined.

Ebinger, Michael H. (Santa Fe, NM); Harris, Ronny D. (Los Alamos, NM)

2010-04-06T23:59:59.000Z

443

High resolution laser spectroscopy of cesium and rubidium molecules with optically induced coherence  

E-Print Network [OSTI]

accurately and take into account Frack-Condon factors. 4. Conclusion In conclusion, we have observed Raman gain in the backward direction in rubidium diatomic molecules. We have performed simulations that support this interpreta- tion. Note here that what...

Chen, Hui

2006-10-30T23:59:59.000Z

444

D&D Toolbox Robotic Deployment of High Resolution Laser Imaging for Characterization  

Broader source: Energy.gov [DOE]

The characterization of complex and/or hazardous facilities for the purposes of planning D&D projects can be excessively time consuming and present unacceptable hazards for personnel who enter...

445

Appending High-Resolution Elevation Data to GPS Speed Traces for Vehicle Energy Modeling and Simulation  

SciTech Connect (OSTI)

Accurate and reliable global positioning system (GPS)-based vehicle use data are highly valuable for many transportation, analysis, and automotive considerations. Model-based design, real-world fuel economy analysis, and the growing field of autonomous and connected technologies (including predictive powertrain control and self-driving cars) all have a vested interest in high-fidelity estimation of powertrain loads and vehicle usage profiles. Unfortunately, road grade can be a difficult property to extract from GPS data with consistency. In this report, we present a methodology for appending high-resolution elevation data to GPS speed traces via a static digital elevation model. Anomalous data points in the digital elevation model are addressed during a filtration/smoothing routine, resulting in an elevation profile that can be used to calculate road grade. This process is evaluated against a large, commercially available height/slope dataset from the Navteq/Nokia/HERE Advanced Driver Assistance Systems product. Results will show good agreement with the Advanced Driver Assistance Systems data in the ability to estimate road grade between any two consecutive points in the contiguous United States.

Wood, E.; Burton, E.; Duran, A.; Gonder, J.

2014-06-01T23:59:59.000Z

446

High-resolution Tangential AXUV Arrays for Radiated Power Density Measurements on NSTX-U  

SciTech Connect (OSTI)

Precise measurements of the local radiated power density and total radiated power are a matter of the uttermost importance for understanding the onset of impurity-induced instabilities and the study of particle and heat transport. Accounting of power balance is also needed for the understanding the physics of various divertor con#12;gurations for present and future high-power fusion devices. Poloidal asymmetries in the impurity density can result from high Mach numbers and can impact the assessment of their flux-surface-average and hence vary the estimates of P[sub]rad (r, t) and (Z[sub]eff); the latter is used in the calculation of the neoclassical conductivity and the interpretation of non-inductive and inductive current fractions. To this end, the bolometric diagnostic in NSTX-U will be upgraded, enhancing the midplane coverage and radial resolution with two tangential views, and adding a new set of poloidally-viewing arrays to measure the 2D radiation distribution. These systems are designed to contribute to the near- and long-term highest priority research goals for NSTX-U which will integrate non-inductive operation at reduced collisionality, with high-pressure, long energy-confinement-times and a divertor solution with metal walls.

Delgado-Aparicio, L [PPPL; Bell, R E [PPPL; Faust, I [MIT; Tritz, K [The Johns Hopkins University, Baltimore, MD, 21209, USA; Diallo, A [PPPL; Gerhardt, S P [PPPL; Kozub, T A [PPPL; LeBlanc, B P [PPPL; Stratton, B C [PPPL

2014-07-01T23:59:59.000Z

447

Seismic data obtained using. 50-caliber machine gun as high-resolution seismic source  

SciTech Connect (OSTI)

A seismic line across a shoestring sandstone served as a test of a .50-caliber machine gun as a high-resolution seismic source in exploring for shallow sandstones. The line crosses part of the Bronson-Xenia oil field, which produces from the Bartlesville sandstone of the Cherokee Group (Pennsylvanian) in Bourbon County, Kansas, at a depth of 622 ft (190 m). The reservoir, which has a flat base and an irregular top, may represent a superposition of fluvial sandstones. The seismic line clearly depicts a lenticular sandstone that is up to 56 ft (17 m) thick. Both the lateral extent of the sandstone body and a slight velocity pull-up of the underlying layers are evident. In addition to the target sandstone, two additional sandstone bodies may be present at the east end of the line, where well control is not available. Analysis of the seismic data indicates that the frequency of the .50-caliber sources is from 30 to 170 Hz. The high frequencies are retained deep into the section. Two shots per shotpoint are the minimum number necessary for acquiring high-quality data, and 12-fold is the minimum acceptable common-depth-point (CDP) coverage. 11 figures.

Seeber, M.D.; Steeples, D.

1986-08-01T23:59:59.000Z

448

Dimensional scaling treatment of stability of atomic anions induced by superintense, high-frequency laser fields  

E-Print Network [OSTI]

and often paradoxical electronic properties of atoms induced by high-frequency superintense radiation fields- lization of multiply charged anions of hydrogen10 and doubly charged anions of helium and lithium atoms.11 of molecular anions. II. LASER ATOM INTERACTION We consider a high-frequency monochromatic electric field

Kais, Sabre

449

Improvement of the Temporal Contrast of High-Power Laser Pulses  

E-Print Network [OSTI]

high gain8 pass amplifier ultrafast pulse cleaner 107 preamplifierJ ultrafast pulse cleaner ASE for pulse amplification. In our laser system, we insert the preamplifier and ultrafast pulse cleaner before for optimizing the performance of the ultrafast pulse cleaner. After passing through the pulse cleaner, the high

450

High-harmonic generation in plasmas from relativistic laser-electron scattering  

E-Print Network [OSTI]

High-harmonic generation in plasmas from relativistic laser-electron scattering S. Banerjee, A. R Results are presented on the generation of high harmonics through the scattering of relativistic electrons to be the emission of even- order harmonics, linear dependence on the electron density, significant amount

Umstadter, Donald

451

High power laser and materials investigation. Final report, 31 July 1978-28 October 1979  

SciTech Connect (OSTI)

This is a combined study of resonant pumped solid state lasers as fusion drivers, and the development of crystalline optical materials suitable for propagation of the high peak powers associated with laser fusion research. During this period of study the concept of rare gas halide lasers was first demonstrated by the lasing of Tm:YLF at 453 nm pumped by the 353 nm energy of XeF. Excited stata densities of 5 x 10/sup 18/ cm/sup -3/ have been attained and spectroscopic measurements show that up to 60% of the pump energy can be converted into useful stored energy. Alternative lasers and pumping schemes are also discussed. In all cases the potential RGH/SS systems are evaluated in respect to internal efficiency and heat loading.

Chicklis, E.P.; Folweiler, R.C.; Pollak, T.M.; Baer, J.

1980-06-01T23:59:59.000Z

452

High damage-resistant Mo mirror for high-power TEA CO/sub 2/ laser systems  

SciTech Connect (OSTI)

A high-purity molybdenum (Mo) mirror was developed by an electron-beam melting method (e.b.m. Mo mirror). For high-power TEA CO/sub 2/ laser, the e.b.m. Mo mirror has two to four times higher surface damage threshold than that of an Au-coated glass mirror and three times longer lifetime than that of a powder metallurgy Mo mirror (p.m. Mo mirror) when laser energy density lower than 60 J/cm/sup 2/ was irradiated with a 0.5-pps repetition rate. It was found that the difference between the e.b.m. Mo mirror and the p.m. Mo mirror at the laser-damage threshold was due to the five surface without voids and the small amount of impurities.

Ichikawa, Y.; Yoshida, K.; Tsunawaki, Y.; Yamanaka, M.; Yamanaka, T.; Yamanaka, C.; Okamoto, H.; Matsusue, N.; Kitajima, K.

1987-09-01T23:59:59.000Z

453

Stimulated Brillouin scattering mirror system, high power laser and laser peening method and system using same  

DOE Patents [OSTI]

A laser system, such as a master oscillator/power amplifier system, comprises a gain medium and a stimulated Brillouin scattering SBS mirror system. The SBS mirror system includes an in situ filtered SBS medium that comprises a compound having a small negative non-linear index of refraction, such as a perfluoro compound. An SBS relay telescope having a telescope focal point includes a baffle at the telescope focal point which blocks off angle beams. A beam splitter is placed between the SBS mirror system and the SBS relay telescope, directing a fraction of the beam to an alternate beam path for an alignment fiducial. The SBS mirror system has a collimated SBS cell and a focused SBS cell. An adjustable attenuator is placed between the collimated SBS cell and the focused SBS cell, by which pulse width of the reflected beam can be adjusted.

Dane, C. Brent (Livermore, CA); Hackel, Lloyd (Livermore, CA); Harris, Fritz B. (Rocklin, CA)

2007-04-24T23:59:59.000Z

454

COMPARISON OF WIND AND WIND SHEAR CLIMATOLOGIES DERIVED FROM HIGH-RESOLUTION RADIOSONDES AND THE ECMWF MODEL  

E-Print Network [OSTI]

COMPARISON OF WIND AND WIND SHEAR CLIMATOLOGIES DERIVED FROM HIGH-RESOLUTION RADIOSONDES wind and its vertical gradient, i.e. wind-shear, is characterized as a function of climate region. For a better representation of the average atmospheric wind and shear and their variabilities, high

Stoffelen, Ad

455

High-resolution x-ray spectroscopy with the EBIT Calorimeter Spectrometer  

SciTech Connect (OSTI)

The EBIT Calorimeter Spectrometer (ECS) is a production-class 36 pixel x-ray calorimeter spectrometer that has been continuously operating at the Electron Beam Ion Trap (EBIT) facility at Lawrence Livermore National Laboratory for almost 2 years. The ECS was designed to be a long-lifetime, turn-key spectrometer that couples high performance with ease of operation and minimal operator intervention. To this end, a variant of the Suzaku/XRS spaceflight detector system has been coupled to a low-maintenance cryogenic system consisting of a long-lifetime liquid He cryostat, and a closed cycle, {sup 3}He pre-cooled adiabatic demagnetization refrigerator. The ECS operates for almost 3 weeks between cryogenic servicing and the ADR operates at 0.05 K for more than 60 hours between automatic recycles under software control. Half of the ECS semiconductor detector array is populated with mid-band pixels that have a resolution of 4.5 eV FWHM, a bandpass from 0.05-12 keV, and a quantum efficiency of 95% at 6 keV. The other half of the array has thick HgTe absorbers that have a bandpass from 0.3 to over 100 keV, an energy resolution of 33 eV FWHM, and a quantum efficiency of 32% at 60 keV. In addition, the ECS uses a real-time, autonomous, data collection and analysis system developed for the Suzaku/XRS instrument and implemented in off-the-shelf hardware for the ECS. Here we will discuss the performance of the ECS instrument and its implementation as a turnkey cryogenic detector system.

Porter, F S; Adams, J S; Beiersdorfer, P; Brown, G V; Clementson, J; Frankel, M; Kahn, S M; Kelley, R L; Kilbourne, C A

2009-10-01T23:59:59.000Z

456

Detailed Hydrographic Feature Extraction from High-Resolution LiDAR Data  

SciTech Connect (OSTI)

Detailed hydrographic feature extraction from high-resolution light detection and ranging (LiDAR) data is investigated. Methods for quantitatively evaluating and comparing such extractions are presented, including the use of sinuosity and longitudinal root-mean-square-error (LRMSE). These metrics are then used to quantitatively compare stream networks in two studies. The first study examines the effect of raster cell size on watershed boundaries and stream networks delineated from LiDAR-derived digital elevation models (DEMs). The study confirmed that, with the greatly increased resolution of LiDAR data, smaller cell sizes generally yielded better stream network delineations, based on sinuosity and LRMSE. The second study demonstrates a new method of delineating a stream directly from LiDAR point clouds, without the intermediate step of deriving a DEM. Direct use of LiDAR point clouds could improve efficiency and accuracy of hydrographic feature extractions. The direct delineation method developed herein and termed “mDn”, is an extension of the D8 method that has been used for several decades with gridded raster data. The method divides the region around a starting point into sectors, using the LiDAR data points within each sector to determine an average slope, and selecting the sector with the greatest downward slope to determine the direction of flow. An mDn delineation was compared with a traditional grid-based delineation, using TauDEM, and other readily available, common stream data sets. Although, the TauDEM delineation yielded a sinuosity that more closely matches the reference, the mDn delineation yielded a sinuosity that was higher than either the TauDEM method or the existing published stream delineations. Furthermore, stream delineation using the mDn method yielded the smallest LRMSE.

Danny L. Anderson

2012-05-01T23:59:59.000Z

457

MAINTAINING HIGH RESOLUTION MASS SPECTROMETRY CAPABILITIES FOR NATIONAL NUCLEAR SECURITY ADMINISTRATION APPLICATIONS  

SciTech Connect (OSTI)

The Department of Energy (DOE) National Nuclear Security Administration (NNSA) has a specialized need for analyzing low mass gas species at very high resolutions. The currently preferred analytical method is electromagnetic sector mass spectrometry. This method allows the NNSA Nuclear Security Enterprise (NSE) to resolve species of similar masses down to acceptable minimum detection limits (MDLs). Some examples of these similar masses are helium-4/deuterium and carbon monoxide/nitrogen. Through the 1980s and 1990s, there were two vendors who supplied and supported these instruments. However, with declining procurements and down turns in the economy, the supply of instruments, service and spare parts from these vendors has become less available, and in some cases, nonexistent. The largest NSE user of this capability is the Savannah River Site (SRS), located near Aiken, South Carolina. The Research and Development Engineering (R&DE) Group in the Savannah River National Laboratory (SRNL) investigated the areas of instrument support that were needed to extend the life cycle of these aging instruments. Their conclusions, as to the focus areas of electromagnetic sector mass spectrometers to address, in order of priority, were electronics, software and hardware. Over the past 3-5 years, the R&DE Group has designed state of the art electronics and software that will allow high resolution legacy mass spectrometers, critical to the NNSA mission, to be operated for the foreseeable future. The funding support for this effort has been from several sources, including the SRS Defense Programs, NNSA Readiness Campaign, Pantex Plant and Sandia National Laboratory. To date, electronics systems have been upgraded on one development system at SRNL, two production systems at Pantex and one production system at Sandia National Laboratory. An NSE working group meets periodically to review strategies going forward. The R&DE Group has also applied their work to the electronics for a Thermal Ionization Mass Spectrometer (TIMS) instrument, which applies a similar mass spectrometric technology for resolving high mass isotopes, such as plutonium and uranium. Due to non-compete clauses for DOE, all work has been performed and applied to instruments which are obsolete and are no longer supported by the original vendor.

Wyrick, S.; Cordaro, J.; Reeves, G.; Mcintosh, J.; Mauldin, C.; Tietze, K.; Varble, D.

2011-06-06T23:59:59.000Z

458

Pulsed laser kinetic studies of liquids under high pressure  

SciTech Connect (OSTI)

A laser flash photolysis kinetic study of 2,2{prime}-bipyridine bidentate chelating ligands with one claw in the first coordination sphere of a molybdenum carbonyl complex has been completed at pressures up to 150 MPa. The reaction mechanism for thermal ring closure is found from activation volumes to change from associative interchange to dissociative interchange as substituents on the 2,2{prime}-bipyridine ligands become bulkier. In a similar study of more rigid, substituted phenanthroline bidentate ligands it was found that substituent bulkiness had little effect on the thermal ring closure mechanism. Stability constants for lithium ion complexes with crown ethers in a room temperature molten salt, fluorescence quantum yields for cresyl violet and several other dyes in solution, and the oxidation of alcohols by OsO{sub 4} have also been investigated.

Eyring, E.M.

1992-09-22T23:59:59.000Z

459

High-Resolution Mass Spectroscopic Analysis of Secondary Organic Aerosol Generated by Ozonolysis of Isoprene  

SciTech Connect (OSTI)

The chemical composition of secondary organic aerosol (SOA) generated from the ozonolysis of isoprene (C5H8) in the presence of an OH scavenger was examined using high-resolution electrospray ionization mass spectrometry (ESI-MS). The chemical composition of SOA is complex, with more than 1000 assigned peaks observed in the positive and negative ion mode spectra. Only a small fraction of peaks corresponds to known products of isoprene oxidation, such as pyruvic acid, glycolic acid, methylglyoxal, etc. The absolute majority of the detected peaks correspond to highly oxidized oligomeric constituents of SOA, with an average O:C molar ratio of ~0.6. The corresponding organic mass (OM) to organic oxygen (OO) ratio is OM/OO?2.4. Approximately 8% of oxygen atoms in SOA are in the form of peroxides as quantified with an iodide test. Double bond equivalency (DBE) factors, representing the sum of all double bonds and rings, increase by 1 for every 2-3 additional carbon atoms in the molecule. The prevalent oligomer building blocks are therefore carbonyls or carboxylic acids with a C2-C3 skeleton. Kendrick analysis suggests that simple aldehydes, specifically formaldehyde, acetaldehyde, and methylglyoxal can serve as monomeric building blocks in the observed oligomers. The large number of reactive functional groups, especially organic peroxides and carbonyls, suggests that isoprene/O3 SOA should be prone to chemical and photochemical aging.

Nguyen, Tran B.; Bateman, Adam P.; Bones, David L.; Nizkorodov, Serguei; Laskin, Julia; Laskin, Alexander

2010-02-01T23:59:59.000Z

460

Solar Flare Chromospheric Line Emission: Comparison Between IBIS High-resolution Observations and Radiative Hydrodynamic Simulations  

E-Print Network [OSTI]

Solar flares involve impulsive energy release, which results in enhanced radiation in a broad spectral and at a wide height range. In particular, line emission from the chromosphere (lower atmosphere) can provide critical diagnostics of plasma heating processes. Thus, a direct comparison between high-resolution spectroscopic observations and advanced numerical modeling results can be extremely valuable, but has not been attempted so far. We present in this paper such a self-consistent investigation of an M3.0 flare observed by the Dunn Solar Telescope's (DST) Interferometric Bi-dimensional Spectrometer (IBIS) on 2011 September 24 that we have modeled with the radiative hydrodynamic code RADYN (Carlsson & Stein 1992, 1997; Abbett & Hawley 1999; Allred et al. 2005). We obtained images and spectra of the flaring region with IBIS in H$\\alpha$ 6563 \\AA\\ and Ca II 8542 \\AA, and with the Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) in X-rays. The latter was used to infer the non-thermal elect...

da Costa, Fatima Rubio; Petrosian, Vahé; Dalda, Alberto Sainz; Liu, Wei

2014-01-01T23:59:59.000Z

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461

High-Resolution Radio Imaging of Gravitational Lensing Candidates in the 1 Jansky BL Lac Sample  

E-Print Network [OSTI]

While BL Lacertae objects are widely believed to be highly beamed, low-luminosity radio galaxies, many radio-selected BL Lacs have extended radio power levels and optical emission lines that are too luminous to be low-luminosity radio galaxies. Also, Stocke & Rector discovered an excess of MgII absorption systems along BL Lac sightlines compared to quasars, suggesting that gravitational lensing may be another means of creating the BL Lac phenomenon in some cases. We present a search for gravitationally-lensed BL Lacs with deep, high-resolution, two-frequency VLA radio maps of seven lensing candidates from the 1 Jansky BL Lac sample. We find that none of these objects are resolved into an Einstein ring like B 0218+357, nor do any show multiple images of the core. All of the lensing candidates that were resolved show a flat-spectrum core and very unusual, steep-spectrum extended morphology that is incompatible with a multiply lensed system. Thus, while these observations do not rule out microlensing, no macrolensing is observed.

T. A. Rector; J. T. Stocke

2003-02-19T23:59:59.000Z

462

Experimental Investigation and High Resolution Simulation of In-Situ Combustion Processes  

SciTech Connect (OSTI)

This final technical report describes work performed for the project 'Experimental Investigation and High Resolution Numerical Simulator of In-Situ Combustion Processes', DE-FC26-03NT15405. In summary, this work improved our understanding of in-situ combustion (ISC) process physics and oil recovery. This understanding was translated into improved conceptual models and a suite of software algorithms that extended predictive capabilities. We pursued experimental, theoretical, and numerical tasks during the performance period. The specific project objectives were (i) identification, experimentally, of chemical additives/injectants that improve combustion performance and delineation of the physics of improved performance, (ii) establishment of a benchmark one-dimensional, experimental data set for verification of in-situ combustion dynamics computed by simulators, (iii) develop improved numerical methods that can be used to describe in-situ combustion more accurately, and (iv) to lay the underpinnings of a highly efficient, 3D, in-situ combustion simulator using adaptive mesh refinement techniques and parallelization. We believe that project goals were met and exceeded as discussed.

Margot Gerritsen; Tony Kovscek

2008-04-30T23:59:59.000Z

463

High-resolution seismology and comparison of synthetic seismograms for the Powderhorn field  

E-Print Network [OSTI]

Figure 40. Amplitude spectra of stacked traces after deconvolution by method 3 79 Figure 41. Sonic and porosity logs of well 811111. . . . 82 Figure 42. Time-depth conversion chart for CDP 53. . . . 86 Figure 43. The impulse-response model. 88 Figure... are dependent on the resolution of the seismic signal. Seismic resolution defines the degree of detail of vertical and lateral changes in the subsurface (position, shape, amplitude and velocities). Vertical resolution determines the ability to distinguish...

Lee, Kyoung-Jin

2012-06-07T23:59:59.000Z

464

High-intensity laser-driven proton acceleration enhancement from hydrogen containing ultrathin targets  

SciTech Connect (OSTI)

Laser driven proton acceleration experiments from micron and submicron thick targets using high intensity (2 × 10{sup 21} W/cm{sup 2}), high contrast (10{sup ?15}) laser pulses show an enhancement of maximum energy when hydrogen containing targets were used instead of non-hydrogen containing. In our experiments, using thin (<1?m) plastic foil targets resulted in maximum proton energies that were consistently 20%–100% higher than when equivalent thickness inorganic targets, including Si{sub 3}N{sub 4} and Al, were used. Proton energies up to 20 MeV were measured with a flux of 10{sup 7} protons/MeV/sr.

Dollar, F.; Reed, S. A.; Matsuoka, T.; Bulanov, S. S.; Chvykov, V.; Kalintchenko, G.; McGuffey, C.; Rousseau, P.; Thomas, A. G. R.; Willingale, L.; Yanovsky, V.; Krushelnick, K.; Maksimchuk, A. [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Center for Ultrafast Optical Science, University of Michigan, Ann Arbor, Michigan 48109 (United States); Litzenberg, D. W. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109 (United States)

2013-09-30T23:59:59.000Z

465

Extended-range grazing-incidence spectrometer for high-resolution extreme ultraviolet measurements on an electron beam ion trap  

SciTech Connect (OSTI)

A high-resolution grazing-incidence grating spectrometer has been implemented on the Livermore electron beam ion traps for performing very high-resolution measurements in the soft x-ray and extreme ultraviolet region spanning from below 10 Å to above 300 Å. The instrument operates without an entrance slit and focuses the light emitted by highly charged ions located in the roughly 50 ?m wide electron beam onto a cryogenically cooled back-illuminated charge-coupled device detector. The measured line widths are below 0.025 Å above 100 Å, and the resolving power appears to be limited by the source size and Doppler broadening of the trapped ions. Comparisons with spectra obtained with existing grating spectrometers show an order of magnitude improvement in spectral resolution.

Beiersdorfer, P.; Magee, E. W.; Brown, G. V.; Träbert, E.; Widmann, K. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Hell, N. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States); Dr. Remeis-Sternwarte and ECAP, Universität Erlangen-Nürnberg, 96049 Bamberg (Germany)

2014-11-15T23:59:59.000Z

466

Influences of carrier diffusion and radial mode field pattern on high speed characteristics for microring lasers  

SciTech Connect (OSTI)

High-speed directly modulated microlasers are potential light sources for on-chip optical interconnection and photonic integrated circuits. In this Letter, dynamic characteristics are studied for microring lasers by rate equation analysis considering radial carrier hole burning and diffusion and experimentally. The coupled modes with a wide radial field pattern and the injection current focused in the edge area of microring resonator can greatly improve the high speed response curve due to the less carrier hole burning. The small-signal response curves of a microring laser connected with an output waveguide exhibit a larger 3?dB bandwidth and smaller roll-off at low frequency than that of the microdisk laser with the same radius of 15??m, which accords with the simulation results.

Lv, Xiao-Meng; Huang, Yong-Zhen, E-mail: yzhuang@semi.ac.cn; Yang, Yue-De; Zou, Ling-Xiu; Long, Heng; Liu, Bo-Wen; Xiao, Jin-Long; Du, Yun [State Key Laboratory on Integrated Optoelectronics, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

2014-04-21T23:59:59.000Z

467

High energy electrons and nuclear phenomena in petawatt laser-solid experiments  

SciTech Connect (OSTI)

The Petawatt laser at LLNL has opened a new regime of laser-matter interactions in which the quiver motion of plasma electrons is fully relativistic with energies extending well above the threshold for nuclear processes. We have developed broad-band magnetic spectrometers to measure the spectrum of high-energy electrons produced in laser-solid target experiments at the Petawatt, and have found that in addition to the expected flux of {approx}few MeV electrons characteristic of the ponderomotive potential, there is a high energy component extending to {approx}100 MeV apparently from plasma acceleration in the underdense pre-formed plasma. The generation of hard bremsstrahlung, photo-nuclear reactions, and preliminary evidence for positron-electron pair production will be discussed.

Cowan, T. E.; Ditmire, T.; Hatchett, S.; Pennington, D. M.; Perry, M. D.; Phillips, T. W.; Wilks, S. C.; Young, P. E. [Lawrence Livermore National Laboratory, Livermore, California (United States); Dong, B.; Takahashi, Y. [University of Alabama, Huntsville, Alabama (United States); Fountain, W.; Parnell, T. [Marshall Space Flight Center, Huntsville, Alabama (United States); Hunt, A. W. [Harvard University, Cambridge, Massachusetts (United States); Johnson, J. [University Space Research Association, Huntsville, Alabama (United States); Kuehl, T. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany)

1999-07-12T23:59:59.000Z

468

High energy electrons and nuclear phenomena in petawatt laser-solid experiments  

SciTech Connect (OSTI)

The Petawatt laser at LLNL has opened a new regime of laser-matter interactions in which the quiver motion of plasma electrons is fully relativistic with energies extending well above the threshold for nuclear processes. We have developed broad-band magnetic spectrometers to measure the spectrum of high-energy electrons produced in laser-solid target experiments at the Petawatt, and have found that in addition to the expected flux of {approximately}few MeV electrons characteristic of the ponderomotive potential, there is a high energy component extending to {approximately}100 MeV apparently from plasma acceleration in the underdense pre-formed plasma. The generation of hard bremsstrahlung, photo-nuclear reactions, and preliminary evidence for positron-electron pair production will be discussed. {copyright} {ital 1999 American Institute of Physics.}

Cowan, T.E.; Ditmire, T.; Hatchett, S.; Pennington, D.M.; Perry, M.D.; Phillips, T.W.; Wilks, S.C.; Young, P.E. [Lawrence Livermore National Laboratory, Livermore, California (United States)] Dong, B. [University of Alabama, Huntsville, Alabama (United States); Parnell, T.; Takahashi, Y. [Marshall Space Flight Center, Huntsville, Alabama (United States)] Hunt, A.W. [Harvard University, Cambridge, Massachusetts (United States)] Johnson, J. [University Space Research Association, Huntsville, Alabama (United States)] Kuehl, T. [Gesellschaft fuer Schwerionenforschung, Darmstadt (Germany)

1999-07-01T23:59:59.000Z

469

Novel Large Area High Resolution Neutron Detector for the Spallation Neutron Source  

SciTech Connect (OSTI)

Neutron scattering is a powerful technique that is critically important for materials science and structural biology applications. The knowledge gained from past developments has resulted in far-reaching advances in engineering, pharmaceutical and biotechnology industries, to name a few. New facilities for neutron generation at much higher flux, such as the SNS at Oak Ridge, TN, will greatly enhance the capabilities of neutron scattering, with benefits that extend to many fields and include, for example, development of improved drug therapies and materials that are stronger, longer-lasting, and more impact-resistant. In order to fully realize this enhanced potential, however, higher neutron rates must be met with improved detection capabilities, particularly higher count rate capability in large size detectors, while maintaining practicality. We have developed a neutron detector with the technical and economic advantages to accomplish this goal. This new detector has a large sensitive area, offers 3D spatial resolution, high sensitivity and high count rate capability, and it is economical and practical to produce. The proposed detector technology is based on B-10 thin film conversion of neutrons in long straw-like gas detectors. A stack of many such detectors, each 1 meter in length, and 4 mm in diameter, has a stopping power that exceeds that of He-3 gas, contained at practical pressures within an area detector. With simple electronic readout methods, straw detector arrays can provide spatial resolution of 4 mm FWHM or better, and since an array detector of such form consists of several thousand individual elements per square meter, count rates in a 1 m^2 detector can reach 2?10^7 cps. Moreover, each individual event can be timetagged with a time resolution of less than 0.1 ?sec, allowing accurate identification of neutron energy by time of flight. Considering basic elemental cost, this novel neutron imaging detector can be commercially produced economically, probably at a small fraction of the cost of He-3 detectors. In addition to neutron scattering science, the fully developed base technology can be used as a rugged, low-cost neutron detector in area monitoring and surveying. Radiation monitors are used in a number of other settings for occupational and environmental radiation safety. Such a detector can also be used in environmental monitoring and remote nuclear power plant monitoring. For example, the Department of Energy could use it to characterize nuclear waste dumps, coordinate clean-up efforts, and assess the radioactive contaminants in the air and water. Radiation monitors can be used to monitor the age and component breakdown of nuclear warheads and to distinguish between weapons and reactor grade plutonium. The UN's International Atomic Energy Agency (IAEA) uses radiation monitors for treaty verification, remote monitoring, and enforcing the non-proliferation of nuclear weapons. As part of treaty verification, monitors can be used to certify the contents of containers during inspections. They could be used for portal monitoring to secure border checkpoints, sea ports, air cargo centers, public parks, sporting venues, and key government buildings. Currently, only 2% of all sea cargo shipped is inspected for radiation sources. In addition, merely the presence of radiation is detected and nothing is known about the radioactive source until further testing. The utilization of radiation monitors with neutron sensitivity and capability of operation in hostile port environments would increase the capacity and effectiveness of the radioactive scanning processes.

Lacy, Jeffrey L

2009-05-22T23:59:59.000Z

470

Laser light backscatter from intermediate and high Z plasmas  

SciTech Connect (OSTI)

In experiments at the Omega Laser Facility [J. M. Soures et al., Fusion Technol. 30, 492 (1996)], stimulated Brillouin backscatter (SBS) from gasbags filled with krypton and xenon gases was ten times lower than from CO{sub 2}-filled gasbags with similar electron densities. The SBS backscatter was a 1%-5% for both 527 and 351 nm interaction beams at an intensity of {approx}10{sup 15} W/cm{sup 2}. The SRS backscatter was less than 1%. The 351 nm interaction beam is below the threshold for filamentation and the SBS occurs in the density plateau between the blast waves. Inverse bremsstrahlung absorption of the incident and SBS light account for the lower reflectivity from krypton than from CO{sub 2}. The 527 nm interaction beam filaments in the blowoff plasma before the beam propagates through the blast wave, where it is strongly absorbed. Thus, most of the 527 nm SBS occurs in the flowing plasma outside the blast waves.

Berger, R. L.; Constantin, C.; Divol, L.; Meezan, N.; Froula, D. H.; Glenzer, S. H.; Suter, L. J.; Niemann, C. [University of California, Lawrence Livermore National Laboratory, P.O. Box 808, Livermore, California 94551 (United States); Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States)

2006-09-15T23:59:59.000Z

471

Refractory oxide hosts for a high power, broadly tunable laser with high quantum efficiency and method of making same  

DOE Patents [OSTI]

Refractory oxide crystals having high-quantum efficiency and high thermal stability for use as broadly tunable laser host materials. The crystals are formed by removing hydrogen from a single crystal of the oxide material to a level below about 10/sup 12/ protons per cm/sup 3/ and subsequently thermochemically reducing the oxygen content of the crystal to form sufficient oxygen anion vacancies so that short-lived F/sup +/ luminescence is produced when the crystal is optically excited.

Chen, Yok; Gonzalez, R.

1985-07-03T23:59:59.000Z

472

Refractory oxide hosts for a high power, broadly tunable laser with high quantum efficiency and method of making same  

DOE Patents [OSTI]

Refractory oxide crystals having high-quantum efficiency and high thermal stability for use as broadly tunable laser host materials. The crystals are formed by removing hydrogen from a single crystal of the oxide material to a level below about 10.sup.12 protons per cm.sup.3 and subsequently thermochemically reducing the oxygen content of the crystal to form sufficient oxygen anion vacancies so that short-lived F.sup.+ luminescence is produced when the crystal is optically excited.

Chen, Yok (Oak Ridge, TN); Gonzalez, Roberto (Madrid, ES)

1986-01-01T23:59:59.000Z

473

Assessment of high-resolution methods for numerical simulations of compressible turbulence with shock waves  

SciTech Connect (OSTI)

Flows in which shock waves and turbulence are present and interact dynamically occur in a wide range of applications, including inertial confinement fusion, supernovae explosion, and scramjet propulsion. Accurate simulations of such problems are challenging because of the contradictory requirements of numerical methods used to simulate turbulence, which must minimize any numerical dissipation that would otherwise overwhelm the small scales, and shock-capturing schemes, which introduce numerical dissipation to stabilize the solution. The objective of the present work is to evaluate the performance of several numerical methods capable of simultaneously handling turbulence and shock waves. A comprehensive range of high-resolution methods (WENO, hybrid WENO/central difference, artificial diffusivity, adaptive characteristic-based filter, and shock fitting) and suite of test cases (Taylor-Green vortex, Shu-Osher problem, shock-vorticity/entropy wave interaction, Noh problem, compressible isotropic turbulence) relevant to problems with shocks and turbulence are considered. The results indicate that the WENO methods provide sharp shock profiles, but overwhelm the physical dissipation. The hybrid method is minimally dissipative and leads to sharp shocks and well-resolved broadband turbulence, but relies on an appropriate shock sensor. Artificial diffusivity methods in which the artificial bulk viscosity is based on the magnitude of the strain-rate tensor resolve vortical structures well but damp dilatational modes in compressible turbulence; dilatation-based artificial bulk viscosity methods significantly improve this behavior. For well-defined shocks, the shock fitting approach yields good results.

Johnsen, Eric [Center for Turbulence Research, Stanford University, Stanford, CA 94305 (United States)], E-mail: johnsen@stanford.edu; Larsson, Johan [Center for Turbulence Research, Stanford University, Stanford, CA 94305 (United States)], E-mail: jola@stanford.edu; Bhagatwala, Ankit V. [Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305 (United States); Cabot, William H. [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Moin, Parviz [Center for Turbulence Research, Stanford University, Stanford, CA 94305 (United States); Olson, Britton J. [Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305 (United States); Rawat, Pradeep S. [Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, CA 90095 (United States); Shankar, Santhosh K. [Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305 (United States); Sjoegreen, Bjoern [Lawrence Livermore National Laboratory, Livermore, CA 94551 (United States); Yee, H.C. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Zhong Xiaolin [Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, CA 90095 (United States); Lele, Sanjiva K. [Department of Aeronautics and Astronautics, Stanford University, Stanford, CA 94305 (United States)

2010-02-20T23:59:59.000Z

474

High-resolution thermal expansion measurements under helium-gas pressure  

SciTech Connect (OSTI)

We report on the realization of a capacitive dilatometer, designed for high-resolution measurements of length changes of a material for temperatures 1.4 K Less-Than-Or-Slanted-Equal-To T Less-Than-Or-Slanted-Equal-To 300 K and hydrostatic pressure P Less-Than-Or-Slanted-Equal-To 250 MPa. Helium ({sup 4}He) is used as a pressure-transmitting medium, ensuring hydrostatic-pressure conditions. Special emphasis has been given to guarantee, to a good approximation, constant-pressure conditions during temperature sweeps. The performance of the dilatometer is demonstrated by measurements of the coefficient of thermal expansion at pressures P Asymptotically-Equal-To 0.1 MPa (ambient pressure) and 104 MPa on a single crystal of azurite, Cu{sub 3}(CO{sub 3}){sub 2}(OH){sub 2}, a quasi-one-dimensional spin S = 1/2 Heisenberg antiferromagnet. The results indicate a strong effect of pressure on the magnetic interactions in this system.

Manna, Rudra Sekhar; Wolf, Bernd; Souza, Mariano de; Lang, Michael [Physics Institute, Goethe University Frankfurt(M), SFB/TR49, D-60438 Frankfurt am Main (Germany)

2012-08-15T23:59:59.000Z

475

HIGH RESOLUTION PREDICTION OF GAS INJECTION PROCESS PERFORMANCE FOR HETEROGENEOUS RESERVOIRS  

SciTech Connect (OSTI)

This report outlines progress in the second quarter of the third year of the DOE project ''High Resolution Prediction of Gas Injection Process Performance for Heterogeneous Reservoirs''. This report presents results of an investigation of the effects of variation in interfacial tension (IFT) on three-phase relative permeability. We report experimental results that demonstrate the effect of low IFT between two of three phases on the three-phase relative permeabilities. In order to create three-phase systems, in which IFT can be controlled systematically, we employed analog liquids composing of hexadecane, n-butanol, isopropanol, and water. Phase composition, phase density and viscosity, and IFT of three-phase system were measured and are reported here. We present three-phase relative permeabilities determined from recovery and pressure drop data using the Johnson-Bossler-Naumann (JBN) method. The phase saturations were obtained from recovery data by the Welge method. The experimental results indicate that the wetting phase relative permeability was not affected by IFT variation whereas the other two-phase relative permeabilities were clearly affected. As IFT decreases the ''oil'' and ''gas'' phases become more mobile at the same phase saturations.

Franklin M. Orr, Jr.

2003-03-31T23:59:59.000Z

476

Doppler tomography of the Little Homunculus: High resolution spectra of [Fe II] 16435 around Eta Carinae  

E-Print Network [OSTI]

High-resolution spectra of [Fe II] 16435 around eta Carinae provide powerful diagnostics of the geometry and kinematics of the ``Little Homunculus'' (LH) growing inside the larger Homunculus nebula. The LH expansion is not perfectly homologous: while low-latitudes are consistent with linear expansion since 1910, the polar caps imply ejection dates around 1920--1930. However, the expansion speed of the LH is slower than the post-eruption wind, so the star's powerful wind may accelerate it. With an initial ejection speed of 200 km/s in 1890, the LH would have been accelerated to its present speed if the mass is roughly 0.1 Msun. This agrees with an independent estimate of the LH mass based on its density and volume. In any case, an ejection after 1930 is ruled out. Using the LH as a probe of the 1890 event, then, it is evident that its most basic physical parameters (total mass and kinetic energy; 0.1 Msun and 10^46.9 ergs, respectively) are orders of magnitude less than during the giant eruption in the 1840s. Thus, the ultimate energy sources were different for these two events -- yet their ejecta have the same bipolar geometry. This clue may point toward a collimation mechanism separate from the underlying causes of the outbursts.

Nathan Smith

2004-12-21T23:59:59.000Z

477

Characterization of Monoenergetic Neutron Reference Fields with a High Resolution Diamond Detector  

E-Print Network [OSTI]

A novel radiation detector based on an artificial single crystal diamond was used to characterize in detail the energy distribution of neutron reference fields at the Physikalisch-Technische Bundesanstalt (PTB) and their contamination with charged particles. The monoenergetic reference fields at PTB in the neutron energy range from 1.5 MeV up to 19 MeV are generated by proton and deuteron beams impinging on solid and gas targets of tritium and deuterium. The energy of the incoming particles and the variation of the angle under which the measurement is performed produce monoenergetic reference fields with different mean energies and line shapes. In this paper we present high resolution neutron spectrometry measurements of different monoenergetic reference fields. The results are compared with calculated spectra taking into account the actual target parameters. Line structures in the order of 80 keV for a neutron energy of 9 MeV were resolved. The shift of the mean energy and the increasing of the width of the ...

Zimbal, A; Nolte, R; Schuhmacher, H

2009-01-01T23:59:59.000Z

478

High resolution n = 3 to n = 2 spectra of neon-like silver  

SciTech Connect (OSTI)

Spectra of the n = 3 to n = 2 transitions in neon-like silver emitted from the Princeton Large Torus have been recorded with a high-resolution Bragg-crystal spectrometer. The measurements cover the wavelength region 3.3 to 4.1 A and include the forbidden 3p ..-->.. 2p electric quadrupole lines. Transitions in the adjacent sodium-like, and aluminum-like charge states of silver have also been observed and identified. The Ly-..cap alpha.. spectra of hydrogen-like argon and iron, the K..cap alpha.. spectra of helium-like argon, potassium, manganese, and iron, and the K..beta.. spectrum of helium-like argon fall in the same wavelength region in first or second order and have been measured concurrently. These spectra provide a coherent set of wavelength reference data obtained with the same spectrometer and from the same tokamak. This set is used as a basis to compare wavelength predictions for one- and two-electron systems to each other and to determine the transition energies of the silver lines with great accuracy.

Beiersdorfer, P.; Bitter, M.; von Goeler, S.; Cohen, S.; Hill, K.W.; Timberlake, J.; Walling, R.S.; Chen, M.H.; Hagelstein, P.L.; Scofield, J.H.

1986-04-01T23:59:59.000Z