Sample records for field short wavelength

  1. Short wavelength laser

    DOE Patents [OSTI]

    Hagelstein, P.L.

    1984-06-25T23:59:59.000Z

    A short wavelength laser is provided that is driven by conventional-laser pulses. A multiplicity of panels, mounted on substrates, are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path. When the panels are illuminated by the conventional-laser pulses, single pass EUV or soft x-ray laser pulses are produced.

  2. Short wavelength laser

    DOE Patents [OSTI]

    Hagelstein, Peter L. (Livermore, CA)

    1986-01-01T23:59:59.000Z

    A short wavelength laser (28) is provided that is driven by conventional-laser pulses (30, 31). A multiplicity of panels (32), mounted on substrates (34), are supported in two separated and alternately staggered facing and parallel arrays disposed along an approximately linear path (42). When the panels (32) are illuminated by the conventional-laser pulses (30, 31), single pass EUV or soft x-ray laser pulses (44, 46) are produced.

  3. PHYSICAL REVIEW A 84, 043423 (2011) Dynamic of rescattering-electron wave packets in strong and short-wavelength laser fields

    E-Print Network [OSTI]

    2011-01-01T23:59:59.000Z

    and short-wavelength laser fields: Roles of Coulomb potential and excited states Yanjun Chen* Beijing and molecules exposed in strong and short- wavelength (shorter than 800 nm) laser fields. Our simulations show the potential, to explain the electronic response in intense and relatively high-frequency laser fields. DOI: 10

  4. Modulation compression for short wavelength harmonic generation

    E-Print Network [OSTI]

    Qiang, J.

    2010-01-01T23:59:59.000Z

    Wavelength Harmonic Generation Ji Qiang Lawrence Berkeleyform a basis for fourth generation light source. Currently,e?ciency was proposed for generation of short wavelength

  5. On Storage Rings for Short Wavelength FELs

    E-Print Network [OSTI]

    Chattopadhyay, S.

    2010-01-01T23:59:59.000Z

    for a hypothetical 144 m long storage ring optimized for FELin the Proceedings On Storage Rings for Short WavelengthLBL-28483 ESG Note-92 ON STORAGE RINGS FOR SHORT WAVELENGTH

  6. Electricity and short wavelength radiation generator

    DOE Patents [OSTI]

    George, E.V.

    1985-08-26T23:59:59.000Z

    Methods and associated apparati for use of collisions of high energy atoms and ions of He, Ne, or Ar with themselves or with high energy neutrons to produce short wavelength radiation (lambda approx. = 840-1300 A) that may be utilized to produce cathode-anode currents or photovoltaic currents.

  7. Short wavelength ion temperature gradient turbulence

    SciTech Connect (OSTI)

    Chowdhury, J.; Ganesh, R. [Institute for Plasma Research, Bhat, Gandhinagar (India); Brunner, S.; Lapillonne, X.; Villard, L. [CRPP, Association EURATOM-Confederation Suisse, EPFL, 1015 Lausanne (Switzerland); Jenko, F. [Max-Planck-Institut fuer Plasmaphysik Boltzmannstr. 2, D-85748 Garching (Germany)

    2012-10-15T23:59:59.000Z

    The ion temperature gradient (ITG) mode in the high wavenumber regime (k{sub y}{rho}{sub s}>1), referred to as short wavelength ion temperature gradient mode (SWITG) is studied using the nonlinear gyrokinetic electromagnetic code GENE. It is shown that, although the SWITG mode may be linearly more unstable than the standard long wavelength (k{sub y}{rho}{sub s}<1) ITG mode, nonlinearly its contribution to the total thermal ion heat transport is found to be low. We interpret this as resulting from an increased zonal flow shearing effect on the SWITG mode suppression.

  8. Source of coherent short wavelength radiation

    DOE Patents [OSTI]

    Villa, Francesco (Alameda, CA)

    1990-01-01T23:59:59.000Z

    An apparatus for producing coherent radiation ranging from X-rays to the far ultraviolet (i.e., 1 Kev to 10 eV) utilizing the Compton scattering effect. A photon beam from a laser is scattered on a high energy electron bunch from a pulse power linac. The short wavelength radiation produced by such scattering has sufficient intensity and spatial coherence for use in high resolution applications such as microscopy.

  9. Short Wavelength Seeding through Compression for Fee Electron Lasers

    E-Print Network [OSTI]

    Qiang, Ji

    2010-01-01T23:59:59.000Z

    tunable short wavelength free electron lasers (FELs) providereduces the laser power needed for the generation of shortbetween the laser ?eld and the electron beam inside a short

  10. Use of Dynamical Undulator Mechanism to Produce Short Wavelength Radiation in Volume FEL (VFEL)

    E-Print Network [OSTI]

    V. G. Baryshevsky; K. G. Batrakov

    2002-09-06T23:59:59.000Z

    VFEL lasing in system with dynamical undulator is described. In this system radiation of long wavelength creates the undulator for lasing on shorter wavelength. Two diffraction gratings with different spatial periods form VFEL resonator. The grating with longer period pumps the resonator with long wavelength radiation to provide necessary amplitude of undulator field. The grating with shorter period makes mode selection for short wavelength radiation. Lasing of such a system in terahertz frequency range is discussed.

  11. 5. Wavelengths and periods of field motions

    E-Print Network [OSTI]

    Finlay, Christopher

    . Using a technique based on the Radon transform [2], we determined the amount of power propagating5. Wavelengths and periods of field motions 2D frequency-wavenumber (FK) power spectra were of the large scale magnetic field at the surface of the core. Here we deconstruct such a model (gufm1

  12. Fluid dynamic issues in continuous wave short wavelength chemical lasers

    SciTech Connect (OSTI)

    Mikatarian, R.R.; Jumper, E.J.; Woolhiser, C.

    1988-01-01T23:59:59.000Z

    This paper addresses fluid dynamic issues of concern in the design and development of Continuous Wave (CW) Short Wavelength Chemical Lasers (SWCLs). Short Wavelength Chemical Laser technology is in its research stage and SWCL concepts are in their evolving mode. Researchers are presently addressing candidate chemical systems and activation concepts. Since these lasers will be flowing systems, it is necessary to discuss both the probable fluid dynamics issues, because of the inherent complexities fluid dynamicist can support this activity. In addition to addressing the SWCL fluid dynamic issues, this paper will review past fluid dynamic activities in high energy lasers and discuss additional research still required. This paper will also address the various levels of fluid dynamic modeling and how these models can be applied in studying the fluid dynamics of Short Wavelength Chemical Lasers. Where it is felt that specific fluid methodologies are not available, but are required in order to conduct specific analyses, they will be defined. 34 refs., 6 figs., 1 tab.

  13. PHYSICAL REVIEW A 83, 013405 (2011) Precision calculation of above-threshold multiphoton ionization in intense short-wavelength laser

    E-Print Network [OSTI]

    Chu, Shih-I

    2011-01-01T23:59:59.000Z

    in intense short-wavelength laser fields: The momentum-space approach and time-dependent generalized to the advance of the intense and short pulse laser technology, the study of ATI phenomenon continues to attract) dynamics of atomic systems driven by intense laser fields. In this approach, the electron wave function

  14. First observations of short wavelength coherent synchrotron radiation (CSR) at BC3

    E-Print Network [OSTI]

    First observations of short wavelength coherent synchrotron radiation (CSR) at BC3 Christopher-FLA) short wavelength CSR at BC3 11th December 2007 1 / 26 #12;Outline 1 Motivation CSR at BC3 End Christopher Behrens (DESY-FLA) short wavelength CSR at BC3 11th December 2007 2 / 26 #12

  15. Attenuated short wavelength buckling and force propagation in a biopolymer-reinforced rod

    E-Print Network [OSTI]

    Shan, Wanliang

    rigidity k and the elastic energy in the medium due to lateral deections of the rod results in a bucklingAttenuated short wavelength buckling and force propagation in a biopolymer-reinforced rod W. L investigate short wavelength buckling of a thin elastic rod embedded in an elastic gelatin biopolymer network

  16. Ion heating and short wavelength fluctuations in a helicon plasma source

    SciTech Connect (OSTI)

    Scime, E. E.; Carr, J. Jr.; Galante, M.; Magee, R. M. [Department of Physics, West Virginia University, Morgantown, WV 26506 (United States); Hardin, R. [Oak Ridge National Laboratory, Oak Ridge, TN 37831 (United States)

    2013-03-15T23:59:59.000Z

    For typical helicon source parameters, the driving antenna can couple to two plasma modes; the weakly damped 'helicon' wave, and the strongly damped, short wavelength, slow wave. Here, we present direct measurements, obtained with two different techniques, of few hundred kHz, short wavelength fluctuations that are parametrically driven by the primary antenna and localized to the edge of the plasma. The short wavelength fluctuations appear for plasma source parameters such that the driving frequency is approximately equal to the lower hybrid frequency. Measurements of the steady-state ion temperature and fluctuation amplitude radial profiles suggest that the anomalously high ion temperatures observed at the edge of helicon sources result from damping of the short wavelength fluctuations. Additional measurements of the time evolution of the ion temperature and fluctuation profiles in pulsed helicon source plasmas support the same conclusion.

  17. Asymptotic description of radially localized short wavelength eigenmodes in a tokamak

    E-Print Network [OSTI]

    Asymptotic description of radially localized short wavelength eigenmodes in a tokamak G. V-driven instabilities in a tokamak. It is shown that eigenmodes of the ballooning type are generated by toroidally

  18. SHORT-WAVELENGTH, SINGLE-PASS FREE-ELECTRON LASERS J. Rossbach, DESY, 22603 Hamburg, Germany

    E-Print Network [OSTI]

    SHORT-WAVELENGTH, SINGLE-PASS FREE-ELECTRON LASERS J. Rossbach, DESY, 22603 Hamburg, Germany in demonstration of high power gain at single- pass free-electron lasers operating in the wavelength range from in the undulator. Eq. (1) exhibits two main advantages of the free-electron laser: the free tunability

  19. Excellent optical thermometry based on short-wavelength upconversion emissions in Er3

    E-Print Network [OSTI]

    Cao, Wenwu

    Excellent optical thermometry based on short-wavelength upconversion emissions in Er3 Yb3 codoped (Doc. ID 175753); published November 22, 2012 Excited by a 980 nm laser, upconversion emissions coupled levels, which can emit the shortest wavelength emissions for optical thermometry known so far

  20. Relativistic Single-Cycled Short-Wavelength Laser Pulse Compressed from a Chirped Pulse Induced by Laser-Foil Interaction

    SciTech Connect (OSTI)

    Ji, L. L.; Shen, B. F.; Li, D. X.; Wang, D.; Leng, Y. X.; Zhang, X. M.; Wen, M.; Wang, W. P.; Xu, J. C.; Yu, Y. H. [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China)

    2010-07-09T23:59:59.000Z

    By particle-in-cell simulation and analysis, we propose a plasma approach to generate a relativistic chirped pulse based on a laser-foil interaction. When two counterpropagating circularly polarized pulses interact with an overdense foil, the driving pulse (with a larger laser field amplitude) will accelerate the whole foil to form a double-layer structure, and the scattered pulse (with a smaller laser field amplitude) is reflected by this flying layer. Because of the Doppler effect and the varying velocity of the layer, the reflected pulse is up-shifted for frequency and chirped; thus, it could be compressed to a nearly single-cycled relativistic laser pulse with a short wavelength. Simulations show that a nearly single-cycled subfemtosecond relativistic pulse can be generated with a wavelength of 0.2 {mu}m after dispersion compensation.

  1. Sub-wavelength position measurements with running wave driving fields

    E-Print Network [OSTI]

    J. Evers; S. Qamar

    2009-01-29T23:59:59.000Z

    A scheme for sub-wavelength position measurements of quantum particles is discussed, which operates with running-wave laser fields as opposed to standing wave fields proposed in previous setups. The position is encoded in the phase of the applied fields rather than in the spatially modulated intensity of a standing wave. Therefore, disadvantages of standing wave schemes such as cases where the atom remains undetected since it is at a node of the standing wave field are avoided. Reversing the directions of parts of the driving laser fields allows to switch between different magnification levels, and thus to optimize the localization.

  2. Low work function surface layers produced by laser ablation using short-wavelength photons

    DOE Patents [OSTI]

    Balooch, Mehdi (Berkeley, CA); Dinh, Long N. (Concord, CA); Siekhaus, Wigbert J. (Berkeley, CA)

    2000-01-01T23:59:59.000Z

    Short-wavelength photons are used to ablate material from a low work function target onto a suitable substrate. The short-wavelength photons are at or below visible wavelength. The elemental composition of the deposit is controlled by the composition of the target and the gaseous environment in which the ablation process is performed. The process is carried out in a deposition chamber to which a short-wavelength laser is mounted and which includes a substrate holder which can be rotated, tilted, heated, or cooled. The target material is mounted onto a holder that spins the target during laser ablation. In addition, the deposition chamber is provided with a vacuum pump, an external gas supply with atomizer and radical generator, a gas generator for producing a flow of molecules on the substrate, and a substrate cleaning device, such as an ion gun. The substrate can be rotated and tilted, for example, whereby only the tip of an emitter can be coated with a low work function material.

  3. Whispering-gallery mirrors for short-wavelength laser cavities: Shapes and tolerances

    SciTech Connect (OSTI)

    Braud, J.P.

    1991-01-01T23:59:59.000Z

    The whispering-gallery mirrors desired for use in short-wavelength laser cavities are seen to be highly aspheric and very different from the shapes encountered in conventional optics. Fabrication tolerance are established by examining the effects of various surface imperfections. The mirrors are found to be relatively insensitive to figures errors. The requirements on surface finish are shown to be fairly strict, though less severe than with normal-incidence optics.

  4. Whispering-gallery mirrors for short-wavelength laser cavities: Shapes and tolerances

    SciTech Connect (OSTI)

    Braud, J.P.

    1991-12-31T23:59:59.000Z

    The whispering-gallery mirrors desired for use in short-wavelength laser cavities are seen to be highly aspheric and very different from the shapes encountered in conventional optics. Fabrication tolerance are established by examining the effects of various surface imperfections. The mirrors are found to be relatively insensitive to figures errors. The requirements on surface finish are shown to be fairly strict, though less severe than with normal-incidence optics.

  5. High detectivity short-wavelength II-VI quantum cascade detector

    SciTech Connect (OSTI)

    Ravikumar, Arvind P., E-mail: aravikum@princeton.edu; Gmachl, Claire F. [Department of Electrical Engineering, Princeton University, Princeton, New Jersey 08544 (United States); Garcia, Thor A.; Tamargo, Maria C. [Department of Chemistry, The Graduate Center and The City College of New York, CUNY, New York, New York 10031 (United States); Jesus, Joel De [Department of Physics, The Graduate Center and The City College of New York, CUNY, New York, New York 10031 (United States)

    2014-08-11T23:59:59.000Z

    We report on the experimental demonstration of a ZnCdSe/ZnCdMgSe-based short-wavelength photovoltaic Quantum Cascade Detector (QCD). The QCD operates in two spectral bands centered around 2.6??m and 3.6??m. Calibrated blackbody measurements yield a peak responsivity of 0.1?mA/W or 2400?V/W at 80?K, and a corresponding 300?K background radiation limited infrared performance detectivity (BLIP) of ?2.5?×?10{sup 10?}cm ?Hz/W. Comparison of background illuminated and dark current-voltage measurements demonstrates a BLIP temperature of 200?K. The device differential resistance-area product, decreases from about 10{sup 6} ? cm{sup 2} at 80?K to about 8000 ? cm{sup 2} at 300?K, indicative of the ultra-low Johnson noise in the detectors.

  6. Near-infrared wavelength intersubband transitions in GaN/AlN short period superlattices

    SciTech Connect (OSTI)

    DeCuir, E. A. Jr.; Fred, Emil; Passmore, B. S.; Muddasani, A.; Manasreh, M. O.; Xie Jinqiao; Morkoc, Hadis; Ware, M. E.; Salamo, G. J. [Department of Electrical Engineering, University of Arkansas, 3217 Bell Engineering Center, Fayetteville, Arkansas 72701 (United States); Department of Electrical and Computer Engineering, Virginia Commonwealth University, 601 W. Main St., Richmond, Virginia 23284-3072 (United States); Department of Physics, University of Arkansas, Fayetteville, Arkansas 72701 (United States)

    2006-10-09T23:59:59.000Z

    Intersubband transitions in GaN/AlN short period superlattices prepared by molecular beam epitaxy were investigated using the optical absorption technique. The peak position wavelengths of these transitions are found to span the spectral range of 1.35-2.90 {mu}m for samples cut into 45 deg. waveguides with GaN quantum well thicknesses ranging between 1.70 and 2.41 nm. The Fermi energy levels are estimated from the carrier concentrations, which were measured using an electrochemical capacitance-voltage profiler. The well widths were inferred from comparing the measured peak position energy of the intersubband transitions and the bound state energy levels calculated using the transfer matrix method.

  7. A Short Wavelength GigaHertz Clocked Fiber-Optic Quantum Key Distribution System

    E-Print Network [OSTI]

    Karen J. Gordon; Veronica Fernandez; Paul D. Townsend; Gerald S. Buller

    2006-05-26T23:59:59.000Z

    A quantum key distribution system has been developed, using standard telecommunications optical fiber, which is capable of operating at clock rates of greater than 1 GHz. The quantum key distribution system implements a polarization encoded version of the B92 protocol. The system employs vertical-cavity surface-emitting lasers with emission wavelengths of 850 nm as weak coherent light sources, and silicon single photon avalanche diodes as the single photon detectors. A distributed feedback laser of emission wavelength 1.3 micro-metres, and a linear gain germanium avalanche photodiode was used to optically synchronize individual photons over the standard telecommunications fiber. The quantum key distribution system exhibited a quantum bit error rate of 1.4%, and an estimated net bit rate greater than 100,000 bits-per-second for a 4.2 km transmission range. For a 10 km fiber range a quantum bit error rate of 2.1%, and estimated net bit rate of greater than 7,000 bits-per-second was achieved.

  8. Analysis, modeling, and design of short-wavelength laser-plasma experiments

    SciTech Connect (OSTI)

    Mead, W.C.; Coggeshall, S.V.; Goldman, S.R.; Stover, E.K.; Goldstone, P.D.; Hauer, A.; Kindel, J.M.; Montierth, L.

    1985-01-01T23:59:59.000Z

    We present analysis and LASNEX modeling of two experiments designed to explore the mechanisms and scaling of laser-plasma coupling in high-Z plasmas. The first used layered Au-on-CH spheres irradiated symmetrically using the Omega (Laboratory for Laser Energetics) 0.35 ..mu..m laser to observe the x-ray emission and energy penetration in gold plasmas. Measurements of the subkilovolt and kilovolt emission from targets with varying Au-coating thicknesses were made using diagnostics of varying spectral, temporal, and spatial resolution. The results indicate that the x-ray conversion efficiency is a function of target size, with larger targets yielding x-ray emission in excellent agreement with calculations. The x-ray emission fall-off with decreasing gold thickness agrees well with predictions. The second experiment used the Novette (Lawrence Livermore National Laboratory) laser to irradiate solid gold disk targets, examining wavelength scaling to 0.26 ..mu..m. The measured subkilovolt x-ray emission is in good agreement with calculations using mildly inhibited thermal electron transport, indicating enhanced target coupling, compared with previous experiments using smaller spot sizes. The experiment also indicates very low suprathermal electron populations, on the order of 0.1% at about 30 keV effective temperature. Finally, we present preliminary plans and designs for experiments which will use the Aurora 5 kJ, 5 ns, 0.25 ..mu..m KrF laser now being constructed at Los Alamos.

  9. Measurements of short wavelength VLF bursts in the auroral ionosphere: A case for electromagnetic mode conversion?

    E-Print Network [OSTI]

    California at Berkeley, University of

    electric field measurements from dipole antennas and an onboard burst memory system. The observation the local lower hybrid frequency (flh) up to the electron plasma or cyclotron frequencies heating in the auroral ionosphere. Vago et al. [1992] and Labelle et al. [1986] have measured Trans

  10. The Shoelace Antenna : a device to induce short-wavelength fluctuations in the edge plasma of the Alcator C-Mod Tokamak

    E-Print Network [OSTI]

    Golfinopoulos, Theodore

    2014-01-01T23:59:59.000Z

    The "Shoelace" antenna is a unique device built to induce short-wavelength fluctuations in the edge plasma of the Alcator C-Mod tokamak, at a wave number and in the frequency range associated with the Quasi-Coherent Mode ...

  11. West Short Pine Hills field, Harding County, South Dakota

    SciTech Connect (OSTI)

    Strothman, B.

    1988-07-01T23:59:59.000Z

    The West Short Pine Hills field is a shallow gas field that produces from the Shannon Sandstone Member, on the Camp Crook anticline in southwestern Harding County, South Dakota. The Alma McCutchin 1-17 Heikkila discovery was drilled in the NW1/4, Sec. 17, T16N, R2E, to a depth of 1600 ft and completed in October 1977 for 600 MCFGD from perforations at 1405-1411 ft. To date, 40 gas wells have been completed with total estimated reserves of more than 20 bcf. The field encompasses 12,000 ac, with a current drill-site spacing unit of 160 ac. The field boundaries are fairly well defined, except on the south edge of the field. The wells range in depth from 1250 to 2200 ft, and cost $60,000-$85,000 to drill and complete. Core and log analyses indicate that the field has 70 ft of net pay, with average porosity of 30% and average permeability of 114 md. Most wells have been completed with nitrogen-sand frac. Williston Basin Interstate Pipeline Company of Bismarck, North Dakota, operates a compressor station and 2.5 mi of 4-in. line that connects the field to their 160 in. north-south transmission line to the Rapid City area. Currently, producers are netting $1.10-$1.25/million Btu. The late Mathew T. Biggs of Casper, Wyoming, was the geologist responsible for mapping and finding this gas deposit.

  12. Photoionization dynamics and angular squeezing phenomenon in intense long-wavelength laser fields

    E-Print Network [OSTI]

    Chu, Shih-I; Zhou, Zhongyuan

    2011-03-11T23:59:59.000Z

    distribution (PAD) of H2 in laser fields are also explored in order to have a further insight into the tunneling photoionization. We find that the PAD is squeezed with the increase of laser wavelength and/or intensity, and thus the photoelectrons focus... direction, and (e)–(h) PADs for different photoelectron energy. 033406-6 PHOTOIONIZATION DYNAMICS AND ANGULAR . . . PHYSICAL REVIEW A 83, 033406 (2011) 0 20 40 60 80 100 0.0 0.2 0.4 0.6 0.8 1.0 (a) ? = 660 nm d2 P/ dE d? E (eV) 0 20 40 60 80 100 0.0 0.2 0...

  13. Algorithm for Computation of Electromagnetic Fields of An Accelerated Short Bunch Inside a Rectangular Chamber

    SciTech Connect (OSTI)

    Novokhatski, Alexander; /SLAC; Sullivan, Michael; /SLAC; ,

    2010-09-14T23:59:59.000Z

    We discuss the feasibility of an application of an implicit finite-difference approximation to calculate the fields of a relativistic bunch moving with no restriction inside a vacuum chamber. We assume that a bunch trajectory is not straight but is inside a vacuum chamber or its branch. The bunch can be deflected by the fields of bending magnets. The bunch can be short enough to produce coherent synchrotron radiation (CSR). Accelerator physicists believe that electromagnetic phenomena of charged beams are governed by Maxwell's equations together with Newton's equations for particle dynamics. To understand the behavior of the beams and radiated fields we just need to find a solution to these equations for the case, which can fully describe the real accelerator environment. So, at first we make a model, which contains all the necessary components, but at the same time can be easily 'inserts' into the equations. Sometimes, it is possible to find analytical solutions, but usually they are only work for one-dimensional cases and rarer for two-dimension cases. To find a solution in general we may transform the equations into a equivalent finite-difference form and solve them using computers. We can find a lot of finite-difference schemes, which approximate Maxwell's equations since the first one that was published in 1966. Most of them are so called explicit schemes. That means that the value of the field at the new time step is calculated only by the field values at the previous time step. Stability conditions for these schemes do not allow a time step to be greater than or equal to a space (mesh) step. This limitation brings an additional troublesome effect for short wavelengths compared a mesh step. We state that this effect works like a frequency dispersion media, which is 'hidden' in the finite-difference equation.

  14. Thermonuclear yield of targets under the action of high-power short-wavelength (lambda< or =1. mu. ) lasers

    SciTech Connect (OSTI)

    Basov, N.G.; Gus'kov, S.Y.; Danilova, G.V.; Demchenko, N.N.; Zmitrenko, N.V.; Karpov, V.Y.; Mishchenko, T.V.; Rozanov, V.B.; Samarskii, A.A.

    1985-06-01T23:59:59.000Z

    A unified optimization scheme is used in a numerical calculation of the dependences of the thermonuclear yield of two-layer shell targets on the absorbed laser energy in the range 0.3--10 mJ for lasers emitting radiation of wavelengths shorter than 1 ..mu...

  15. 2nd conference on Intense field- Short Wavelength Atomic and Molecular

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >InternshipDepartment ofAugustDecember8th Meeting of the14Processes -

  16. 2nd conference on Intense field- Short Wavelength Atomic and Molecular

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItemResearch >InternshipDepartment ofAugustDecember8th Meeting of the14Processes

  17. Rapid production of large-area deep sub-wavelength hybrid structures by femtosecond laser light-field tailoring

    SciTech Connect (OSTI)

    Wang, Lei; Chen, Qi-Dai, E-mail: chenqd@jlu.edu.cn, E-mail: hbsun@jlu.edu.cn; Yang, Rui; Xu, Bin-Bin; Wang, Hai-Yu [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); Yang, Hai; Huo, Cheng-Song; Tu, Hai-Ling [General Research Institute for Nonferrous Metals, Beijing 100088 (China); Sun, Hong-Bo, E-mail: chenqd@jlu.edu.cn, E-mail: hbsun@jlu.edu.cn [State Key Laboratory on Integrated Optoelectronics, College of Electronic Science and Engineering, Jilin University, 2699 Qianjin Street, Changchun 130012 (China); College of Physics, Jilin University, 119 Jiefang Road, Changchun 130023 (China)

    2014-01-20T23:59:59.000Z

    The goal of creation of large-area deep sub-wavelength nanostructures by femtosecond laser irradiation onto various materials is being hindered by the limited coherence length. Here, we report solution of the problem by light field tailoring of the incident beam with a phase mask, which serves generation of wavelets. Direct interference between the wavelets, here the first-order diffracted beams, and interference between a wavelet and its induced waves such as surface plasmon polariton are responsible for creation of microgratings and superimposed nanogratings, respectively. The principle of wavelets interference enables extension of uniformly induced hybrid structures containing deep sub-wavelength nanofeatures to macro-dimension.

  18. Investigation of the effect of bilayer membrane structures and fluctuation amplitudes on SANS/SAXS profile for short membrane wavelength

    SciTech Connect (OSTI)

    Lee, Victor; Hawa, Takumi [School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, Oklahoma 73019 (United States)] [School of Aerospace and Mechanical Engineering, The University of Oklahoma, Norman, Oklahoma 73019 (United States)

    2013-09-28T23:59:59.000Z

    The effect of bilayer membrane structures and fluctuation amplitudes on small angle neutron scattering (SANS) and small angle X-ray scattering (SAXS) profile is investigated based on harmonic motions of the surfactant bilayers with bending as well as thickness fluctuation motions. In this study we consider the case in which the wavelength of the bilayer membrane is shorter than the thickness of the membrane. We find that the thickness of the surfactant bilayer membrane, d{sub m}, affects both q{sub dip} and q{sub peak} of I(q,0) profile, and that the fluctuation amplitude, a, of the membrane changes the peak of I(q,0). A simple formula is derived to estimate the thickness of the bilayer based on the q{sub dip} of the profile obtained from the simulation. The resulting estimates of the thickness of the bilayer with harmonic motion showed accuracy within 1%. Moreover, the bilayer thicknesses estimated from the proposed formula show an excellent agreement with the SANS and SAXS experimental results available in the literatures. We also propose a curve fit model, which describes the relationship between the fluctuation amplitude and the normalized q{sub peak} ratio. The present results show the feasibility of the simple formula to estimate the fluctuation amplitude based on the SANS and SAXS profiles.

  19. RF performance of short channel graphene field-effect transistor

    E-Print Network [OSTI]

    Wu, Y. Q.

    In this paper, the authors present experimental studies on transport characteristics of graphene FETs with channel lengths down to 70 nm. The factors limiting the performance of short channel graphene devices are discussed. ...

  20. Short wavelength turbulence generated by shear in the quiescent H-mode edge on DIII–D

    SciTech Connect (OSTI)

    Rost, J. C.; Porkolab, M.; Dorris, J. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Burrell, K. H. [General Atomics, P.O. Box 85608, San Diego, California 92186-5608 (United States)

    2014-06-15T23:59:59.000Z

    A region of turbulence with large radial wavenumber (k{sub r}?{sub s}>1) is found in the high-shear portion of the plasma edge in Quiescent H-mode (QH-mode) on DIII–D using the Phase Contrast Imaging (PCI) diagnostic. At its peak outside the minimum of the E{sub r} well, the turbulence exhibits large amplitude n{sup ~}/n?40%, with large radial wavenumber |k{sup ¯}{sub r}/k{sup ¯}{sub ?}|?11 and short radial correlation length L{sub r}/?{sub i}?0.2. The turbulence inside the E{sub r} well minimum is characterized by the opposite sign in radial wavenumber from that of turbulence outside the minimum, consistent with the expected effects of velocity shear. The PCI diagnostic provides a line-integrated measurement of density fluctuations, so data are taken during a scan of plasma position at constant parameters to allow the PCI to sample a range in k{sub r}/k{sub ?}. Analysis of the Doppler shift and plasma geometry allows the turbulence to be localized to a narrow region 3?mm inside the last closed flux surface, outside the minimum of the E{sub r} well. The turbulence amplitude and radial wavenumber and correlation length are determined by fitting the PCI results with a simple non-isotropic turbulence model with two regions of turbulence. These PCI observations, made in QH-mode, are qualitatively similar to those made in standard edge localized modes (ELM)-free H-mode and between ELMs, suggesting a similar role for large k{sub r} turbulence there.

  1. Transmittance and near-field characterization of sub-wavelength tapered optical fibers

    E-Print Network [OSTI]

    Fedja Orucevic; Valérie Lefèvre-Seguin; Jean Hare

    2008-02-20T23:59:59.000Z

    We have produced high transmission sub-wavelength tapered optical fibers for the purpose of whispering gallery mode coupling in fused silica microcavities at 780 nm. A detailed analysis of the fiber transmittance evolution during tapering is demonstrated to reflect precisely the mode coupling and cutoff in the fiber. This allows to control the final size, the number of guided modes and their effective index. These results are checked by evanescent wave mapping measurements on the resulting taper.

  2. Near- and far-field measurements of phase-ramped frequency selective surfaces at infrared wavelengths

    SciTech Connect (OSTI)

    Tucker, Eric; Boreman, Glenn, E-mail: gboreman@uncc.edu [Department of Physics and Optical Science, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, North Carolina 28223 (United States); D'Archangel, Jeffrey [CREOL, The College of Optics and Photonics, University of Central Florida, 4304 Scorpius St., Orlando, Florida 32816 (United States); Raschke, Markus B. [Department of Physics, Department of Chemistry, and JILA, University of Colorado, 390 UCB, Boulder, Colorado 80309 (United States)

    2014-07-28T23:59:59.000Z

    Near- and far-field measurements of phase-ramped loop and patch structures are presented and compared to simulations. The far-field deflection measurements show that the phase-ramped structures can deflect a beam away from specular reflection, consistent with simulations. Scattering scanning near-field optical microscopy of the elements comprising the phase ramped structures reveals part of the underlying near-field phase contribution that dictates the far-field deflection, which correlates with the far-field phase behavior that was expected. These measurements provide insight into the resonances, coupling, and spatial phase variation among phase-ramped frequency selective surface (FSS) elements, which are important for the performance of FSS reflectarrays.

  3. Development of three-wavelength CCD image pyrometer used for the temperature field measurements of continuous casting billets

    SciTech Connect (OSTI)

    Xie, Zhi; Bai, Haicheng [State Key Laboratory of Synthetical Automation for Process Industries, School of Information Science and Engineering, Northeastern University, Shenyang 110819 (China)] [State Key Laboratory of Synthetical Automation for Process Industries, School of Information Science and Engineering, Northeastern University, Shenyang 110819 (China)

    2014-02-15T23:59:59.000Z

    This paper develops an imaging based three-color pyrometer for the monitoring of temperature distribution in a continuous casting billet. A novel optical device, together with an embedded electronic system, is designed to sequentially collect a dark image and three thermal images with specified wavelengths on a same monochromatic charge-coupled-device (CCD). The three thermal images provide the basis for the determination of target temperature, while the dark image is used to online eliminate the dark noise of CCD with a differential method. This image pyrometer is not only independent of target emissivity but also overcomes the dissimilarity of measuring accuracy between the micro-sensors of CCD resulted from the non-uniformity of pixels’ intensity response and the vignetting of optical system. Furthermore, a precise two-color temperature field measuring model on the CCD pyrometer is established, based on which a self-adaptive light-integration mechanism is presented. Compared with the traditional fixed light-integration method, the measuring range of the pyrometer is greatly extended and its sensitivity in low temperature segment is improved. The test results in a steel factory demonstrate that the pyrometer is capable of meeting the requirement of surface temperature measurements about casting billets. Reliability and accuracy of measurement results are also discussed herein.

  4. Title: The recollision model in ultra-short light fields Prof. H.W. van der Hart Description

    E-Print Network [OSTI]

    Paxton, Anthony T.

    advances in laser technology have enabled scientists to create ultra-short light pulses with a durationTitle: The recollision model in ultra-short light fields Prof. H.W. van der Hart Description Recent of the current questions in attosecond physics is the question of how ultra-short light pulses can be shaped

  5. Key words: GPS, attitude, inertial GPS was used with ultra-short baselines (2-3 carrier wavelengths) in a triple antenna configuration to obtain aircraft atti-

    E-Print Network [OSTI]

    Stanford University

    Abstract Key words: GPS, attitude, inertial GPS was used with ultra-short baselines (2-3 carrier and yaw respectively. The accuracy and robustness of the system was enhanced by combining the ultra short is currently obtained by spinning rotor or ring laser gyros. In General Aviation (GA) applications a vertical

  6. Short cycle pulse sequence for dynamical decoupling of local fields and dipole-dipole interactions

    E-Print Network [OSTI]

    S. A. Moiseev; V. A. Skrebnev

    2014-12-11T23:59:59.000Z

    We propose a new pulse sequence for dynamical averaging of the dipole-dipole interactions and inhomogeneities of the magnetic fields in the nuclear spin system. The sequence contains a short cycle of the periodic resonant pulse excitation that offers new possibilities for implementing the long-lived multi-qubit quantum memory on the condensed spin ensembles that are so important for construction of universal quantum computer and long-distance quantum communications.

  7. Isolated short attosecond pulse generation in an orthogonally polarized multicycle chirped laser field

    SciTech Connect (OSTI)

    Xu Junjie [State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, P.O. Box 800-211, Shanghai 201800 (China)

    2011-03-15T23:59:59.000Z

    We theoretically demonstrate the generation of a high-order harmonic and isolated attosecond pulse in an orthogonally polarized laser field, which is synthesized by an 800-nm chirped laser pulse and an 800-nm chirp-free laser pulse. Owing to the instantaneous frequency increasingly reducing close to the center of the driving pulse, the extreme ultraviolet supercontinuum for the chirped synthesized field is even broader than that for an orthogonal chirp-free two-color laser field. It is found that the broadband supercontinuum spectrum can be achieved for the driving pulse with ten and above optical cycles. After phase compensation an isolated attosecond pulse with a duration of {approx}16 as is produced. Furthermore, the optimization of the chirping rate parameters is investigated to achieve cutoff extension and an isolated short attosecond pulse.

  8. Portable dual field gradient force multichannel flow cytometer device with a dual wavelength low noise detection scheme

    DOE Patents [OSTI]

    James, Conrad D; Galambos, Paul C; Derzon, Mark S; Graf, Darin C; Pohl, Kenneth R; Bourdon, Chris J

    2012-10-23T23:59:59.000Z

    Systems and methods for combining dielectrophoresis, magnetic forces, and hydrodynamic forces to manipulate particles in channels formed on top of an electrode substrate are discussed. A magnet placed in contact under the electrode substrate while particles are flowing within the channel above the electrode substrate allows these three forces to be balanced when the system is in operation. An optical detection scheme using near-confocal microscopy for simultaneously detecting two wavelengths of light emitted from the flowing particles is also discussed.

  9. Wavelength-dependent photochemistry of W(CO){sub 4}(en) (en = ethylenediamine): Evidence for distinct chemical reactivities from singlet and triplet ligand field excited states

    SciTech Connect (OSTI)

    Panesar, R.S.; Dunwoody, N.; Lees, A.J. [State Univ. of New York, Binghamton, NY (United States). Dept. of Chemistry] [State Univ. of New York, Binghamton, NY (United States). Dept. of Chemistry

    1998-04-06T23:59:59.000Z

    Studies of the photophysical and photochemical properties of organometallic compounds have now been extensively performed for over 25 years. In considering the photoreactivity of such complexes, it has usually been assumed that their singlet excited states are extremely short-lived and unreactive as a consequence of effective intersystem crossing mechanisms facilitated by the heavy metal and rapid internal conversions to the ground state. In this paper the authors report quantitative photochemical measurements obtained for W(CO){sub 4}(en) (en = ethylenediamine) following excitation into the lowest energy LF absorption manifold at several wavelengths. This system is of particular significance because, unlike most other substituted metal carbonyl complexes, its lowest lying LF absorption band is well removed from other electronic transitions and the lowest energy LF triplet absorption is a distinctive feature of the spectrum. Following excitation at various wavelengths, therefore, it is possible to populate the LF single and triplet energy levels exclusively and determine their quantitative photochemical reactivities directly. The results for W(CO){sub 4}(en) demonstrate conclusively that the LF excited states undergo separate photosubstitutional pathways and that reaction from the lowest lying LF triplet state takes place with a substantially reduced photoefficiency.

  10. Magnetic Fields in Gamma-Ray Bursts: A Short Racah Institute for Physics, The Hebrew University, Jerusalem, 91904 Israel

    E-Print Network [OSTI]

    Jensen, Grant J.

    Magnetic Fields in Gamma-Ray Bursts: A Short Overview Tsvi Piran Racah Institute for Physics Abstract. Magnetic fields play a crucial role in the physics of Gamma-Ray Bursts (GRBs). Strong thirty years, after the discovery of Gamma-Ray bursts (GRBs) we have now a reasonable GRB model

  11. Electron acceleration by an intense short pulse laser in a static magnetic field in vacuum K. P. Singh*

    E-Print Network [OSTI]

    Roy, Subrata

    Electron acceleration by an intense short pulse laser in a static magnetic field in vacuum K. P by a laser pulse having Gaussian radial and temporal profiles of intensity has been studied in a static to be the same as that of the magnetic field of the laser pulse. The electron gains considerable energy

  12. A multi-wavelength survey of AGN in the XMM-LSS field: I. Quasar selection via the KX technique

    E-Print Network [OSTI]

    Nakos, Th; Andreon, S; Surdej, J; Riaud, P; Hatziminaoglou, E; Garcet, O; Alloin, D; Baes, M; Galaz, G; Pierre, M; Quintana, H; Page, M J; Tedds, J A; Ceballos, M T; Corral, A; Ebrero, J; Krumpe, M; Mateos, S

    2008-01-01T23:59:59.000Z

    AIMS: We present a sample of candidate quasars selected using the KX-technique. The data cover 0.68 deg^2 of the X-ray Multi-Mirror (XMM) Large-Scale Structure (LSS) survey area where overlapping multi-wavelength imaging data permits an investigation of the physical nature of selected sources. METHODS: The KX method identifies quasars on the basis of their optical (R and z') to near-infrared (Ks) photometry and point-like morphology. We combine these data with optical (u*,g'r',i',z') and mid-infrared (3.6-24 micron) wavebands to reconstruct the spectral energy distributions (SEDs) of candidate quasars. RESULTS: Of 93 sources selected as candidate quasars by the KX method, 25 are classified as quasars by the subsequent SED analysis. Spectroscopic observations are available for 12/25 of these sources and confirm the quasar hypothesis in each case. Even more, 90% of the SED-classified quasars show X-ray emission, a property not shared by any of the false candidates in the KX-selected sample. Applying a photometr...

  13. A multi-wavelength survey of AGN in the XMM-LSS field: I. Quasar selection via the KX technique

    E-Print Network [OSTI]

    Th. Nakos; J. P. Willis; S. Andreon; J. Surdej; P. Riaud; E. Hatziminaoglou; O. Garcet; D. Alloin; M. Baes; G. Galaz; M. Pierre; H. Quintana; M. J. Page; J. A. Tedds; M. T. Ceballos; A. Corral; J. Ebrero; M. Krumpe; S. Mateos

    2009-02-24T23:59:59.000Z

    AIMS: We present a sample of candidate quasars selected using the KX-technique. The data cover 0.68 deg^2 of the X-ray Multi-Mirror (XMM) Large-Scale Structure (LSS) survey area where overlapping multi-wavelength imaging data permits an investigation of the physical nature of selected sources. METHODS: The KX method identifies quasars on the basis of their optical (R and z') to near-infrared (Ks) photometry and point-like morphology. We combine these data with optical (u*,g'r',i',z') and mid-infrared (3.6-24 micron) wavebands to reconstruct the spectral energy distributions (SEDs) of candidate quasars. RESULTS: Of 93 sources selected as candidate quasars by the KX method, 25 are classified as quasars by the subsequent SED analysis. Spectroscopic observations are available for 12/25 of these sources and confirm the quasar hypothesis in each case. Even more, 90% of the SED-classified quasars show X-ray emission, a property not shared by any of the false candidates in the KX-selected sample. Applying a photometric redshift analysis to the sources without spectroscopy indicates that the 25 sources classified as quasars occupy the interval 0.7 < z < 2.5. The remaining 68/93 sources are classified as stars and unresolved galaxies.

  14. Fast magnetic field annihilation in the relativistic collisionless regime driven by two ultra-short high-intensity laser pulses

    E-Print Network [OSTI]

    Gu, Y J; Kumar, D; Liu, Y; Singh, S K; Esirkepov, T Zh; Bulanov, S V; Weber, S; Korn, G

    2015-01-01T23:59:59.000Z

    The magnetic quadrupole structure formation during the interaction of two ultra-short high power laser pulses with a collisionless plasma is demonstrated with 2.5-dimensional particle-in-cell simulations. The subsequent expansion of the quadrupole is accompanied by magnetic field annihilation in the ultrarelativistic regime, when the magnetic field can not be sustained by the plasma current. This results in a dominant contribution of the displacement current exciting a strong large scale electric?field. This field leads to the conversion of magnetic energy into kinetic energy of accelerated electrons inside the thin current sheet.

  15. Inversion symmetry breaking of atomic bound states in strong and short laser fields

    E-Print Network [OSTI]

    Stooß, Veit; Ott, Christian; Blättermann, Alexander; Ding, Thomas; Pfeifer, Thomas

    2015-01-01T23:59:59.000Z

    In any atomic species, the spherically symmetric potential originating from the charged nucleus results in fundamental symmetry properties governing the structure of atomic states and transition rules between them. If atoms are exposed to external electric fields, these properties are modified giving rise to energy shifts such as the AC Stark-effect in varying fields and, contrary to this in a constant (DC) electric field for high enough field strengths, the breaking of the atomic symmetry which causes fundamental changes in the atom's properties. This has already been observed for atomic Rydberg states with high principal quantum numbers. Here, we report on the observation of symmetry breaking effects in Helium atoms for states with principal quantum number n=2 utilizing strong visible laser fields. These findings were enabled by temporally resolving the dynamics better than the sub-optical cycle of the applied laser field, utilizing the method of attosecond transient absorption spectroscopy (ATAS). We ident...

  16. Stable Mean Field Solution of a Short-Range Interacting SO(3) Quantum Heisenberg Spin-Glass

    E-Print Network [OSTI]

    C. M. S. da Conceição; E. C. Marino

    2008-02-03T23:59:59.000Z

    We present a mean-field solution for a quantum, short-range interacting, disordered, SO(3) Heisenberg spin model, in which the Gaussian distribution of couplings is centered in an AF coupling $\\bar J>0$, and which, for weak disorder, can be treated as a perturbation of the pure AF Heisenberg system. The phase diagram contains, apart from a N\\'eel phase at T=0, spin-glass and paramagnetic phases whose thermodynamic stability is demonstrated by an analysis of the Hessian matrix of the free-energy. The magnetic susceptibilities exhibit the typical cusp of a spin-glass transition.

  17. Analytically derived limits on short-range fifth forces from quantum states of neutrons in the Earth's gravitational field

    E-Print Network [OSTI]

    Alexander Westphal; Hartmut Abele; Stefan Baessler

    2007-03-12T23:59:59.000Z

    Recently, quantum states of ultra-cold neutrons in the Earth's gravitational field have been observed for the first time. From the fact that they are consistent with Newtonian gravity on the 10 %-level, analytical limits on alpha and lambda of short-range Yukawa-like additional interactions are derived between lambda = 1 micrometer and 1 mm. We arrive for lambda > 10 micrometer at alpha < 2 \\cdot 10^11 at 90 % confidence level. This translates into a limit g_s g_p / (\\hbar c) < 2 \\cdot 10^{-15} on the pseudo-scalar coupling of axions in the previously experimentally unaccessible astrophysical axion window.

  18. An evaluation of the Gilian TRACEAIR Organic Vapor Monitoring Diffusive Badge in measuring short-term exposure levels of benzene under field conditions 

    E-Print Network [OSTI]

    Pierce, Mark Edward

    1996-01-01T23:59:59.000Z

    The objective of this research is to evaluate the performance of the Gilian TRACEAIR Organic Vapor Monitoring I (OVMI) Diffusive Badge in measuring short-term benzene exposures under field conditions. In general, a diffusive badge is a device which...

  19. Laboratory Studies of the Short-term Responses of Freshwater Fish to Electromagnetic Fields

    SciTech Connect (OSTI)

    Bevelhimer, Mark S [ORNL; Cada, Glenn F [ORNL; Fortner, Allison M [ORNL; Schweizer, Peter E [ORNL; Riemer, Kristina P [ORNL

    2013-01-01T23:59:59.000Z

    Hydrokinetic energy technologies are being proposed as an environmentally preferred means of generating electricity from river and tidal currents. Among the potential issues that must be investigated in order to resolve environmental concerns are the effects on aquatic organisms of electromagnetic fields created by underwater generators and transmission cables. The behavioral responses of common freshwater fishes to static and variable electromagnetic fields (EMF) that may be emitted by hydrokinetic projects were evaluated in laboratory experiments. Various fish species were exposed to either static (DC) EMF fields created by a permanent bar magnet or variable (AC) EMF fields created by a switched electromagnet for 48 h, fish locations were recorded with a digital imaging system, and changes in activity level and distribution relative to the magnet position were quantified at 5-min intervals. Experiments with fathead minnows, redear sunfish, striped bass, lake sturgeon, and channel catfish produced mixed results. Except for fathead minnows there was no effect on activity level. Only redear sunfish and channel catfish exhibited a change in distribution relative to the position of the magnet with an apparent attraction to the EMF source. In separate experiments, rapid behavioral responses of paddlefish and lake sturgeon to onset of the AC field were recorded with high-speed video. Paddlefish did not react to a variable, 60-Hz magnetic field like that which would be emitted by an AC generator or cable, but lake sturgeon consistently responded to the variable, AC-generated magnetic field with a variety of altered swimming behaviors. These results will be useful for determining under what circumstances cables or generators need to be positioned to minimize interactions with sensitive species.

  20. Precision calculation of above-threshold multiphoton ionization in intense short-wavelength laser fields: The momentum-space approach and time-dependent generalized pseudospectral method

    E-Print Network [OSTI]

    Chu, Shih-I; Zhou, Zhongyuan

    2011-01-19T23:59:59.000Z

    . Villoresi, M. Nisoli, S. Stagira, E. Priori, and S. De Silvestri, Nature (London) 414, 182 (2001). [26] G. G. Paulus, F. Lindner, H. Walther, A. Baltuska, E. Goulielmakis, M. Lezius, and F. Krausz, Phys. Rev. Lett. 91, 253004 (2003). [27] A. Rudenko, K.... Zrost, C. D. Schro¨ter, V. L. B. de Jesus, B. Feuerstein, R. Moshammer, and J. Ullrich, J. Phys. B 37, L407 (2004). [28] A. Rudenko, K. Zrost, T. Ergler, A. B. Voitkiv, B. Najjari, V. L. B. de Jesus, B. Feuerstein, C. D. Schro¨ter, R. Moshammer, and J...

  1. ASHRAE Transactions: Symposia 617 The field validation of a short time step temperature

    E-Print Network [OSTI]

    Ghajar, Afshin J.

    consumption, based on predicted and measured heat pump entering fluid temperatures,is compared and discussed heat exchanger borehole (Yavuzturk et al. 1999), a comparison of model predictions to actual field data response factor model is presented using actual operational data from an elementary school building

  2. Quantum field theory solution for a short-range interacting SO(3) quantum spin-glass

    E-Print Network [OSTI]

    C. M. S. da Conceição; E. C. Marino

    2009-03-02T23:59:59.000Z

    We study the quenched disordered magnetic system, which is obtained from the 2D SO(3) quantum Heisenberg model, on a square lattice, with nearest neighbors interaction, by taking a Gaussian random distribution of couplings centered in an antiferromagnetic coupling, $\\bar J>0$ and with a width $\\Delta J$. Using coherent spin states we can integrate over the random variables and map the system onto a field theory, which is a generalization of the SO(3) nonlinear sigma model with different flavors corresponding to the replicas, coupling parameter proportional to $\\bar J$ and having a quartic spin interaction proportional to the disorder ($\\Delta J$). After deriving the CP$^1$ version of the system, we perform a calculation of the free energy density in the limit of zero replicas, which fully includes the quantum fluctuations of the CP$^1$ fields $z_i$. We, thereby obtain the phase diagram of the system in terms of ($T, \\bar J, \\Delta J$). This presents an ordered antiferromagnetic (AF) phase, a paramagnetic (PM) phase and a spin-glass (SG) phase. A critical curve separating the PM and SG phases ends at a quantum critical point located between the AF and SG phases, at T=0. The Edwards-Anderson order parameter, as well as the magnetic susceptibilities are explicitly obtained in each of the three phases as a function of the three control parameters. The magnetic susceptibilities show a Curie-type behavior at high temperatures and exhibit a clear cusp, characteristic of the SG transition, at the transition line. The thermodynamic stability of the phases is investigated by a careful analysis of the Hessian matrix of the free energy. We show that all principal minors of the Hessian are positive in the limit of zero replicas, implying in particular that the SG phase is stable.

  3. Temperature field analysis of single layer TiO{sub 2} film components induced by long-pulse and short-pulse lasers

    SciTech Connect (OSTI)

    Wang Bin; Zhang Hongchao; Qin Yuan; Wang Xi; Ni Xiaowu; Shen Zhonghua; Lu Jian

    2011-07-10T23:59:59.000Z

    To study the differences between the damaging of thin film components induced by long-pulse and short-pulse lasers, a model of single layer TiO{sub 2} film components with platinum high-absorptance inclusions was established. The temperature rises of TiO{sub 2} films with inclusions of different sizes and different depths induced by a 1 ms long-pulse and a 10 ns short-pulse lasers were analyzed based on temperature field theory. The results show that there is a radius range of inclusions that corresponds to high temperature rises. Short-pulse lasers are more sensitive to high-absorptance inclusions and long-pulse lasers are more easily damage the substrate. The first-damage decision method is drawn from calculations.

  4. New rest wavelength determinations for 7 mid-infrared fine structure lines by ISO-SWS

    E-Print Network [OSTI]

    H. Feuchtgruber; D. Lutz; D. A. Beintema

    2001-05-15T23:59:59.000Z

    Observations of the planetary nebulae NGC6302, NGC6543 and NGC7027 by the Short Wavelength Spectrometer (SWS) on board the Infrared Space Observatory (ISO) have been used to determine rest wavelengths of spectral lines. We report on improved accuracies for wavelengths of 7 mid-infrared ionic fine structure lines.

  5. The Long Wavelength Array System Technical Requirements

    E-Print Network [OSTI]

    Ellingson, Steven W.

    (frequency) DR Dynamic Range EMC Electromagnetic Compatibility FOV Field of View G.N.D. Galactic Noise Intermediate Array with 16 antennas (core) MCS Monitor and Control System ns nanosecond RFI Radio FrequencyThe Long Wavelength Array System Technical Requirements Version: Draft #9 2007-November-19 Compiled

  6. Radio Wavelength Observatories within the Exploration Architecture

    E-Print Network [OSTI]

    J. Lazio; R. J. Macdowall; J. Burns; L. Demaio; D. L. Jones; K. W. Weiler

    2007-01-26T23:59:59.000Z

    Observations at radio wavelengths address key problems in astrophysics, astrobiology, and lunar structure including the first light in the Universe (the Epoch of Reionization), the presence of magnetic fields around extrasolar planets, particle acceleration mechanisms, and the structure of the lunar ionosphere. Moreover, achieving the performance needed to address these scientific questions demands observations at wavelengths longer than those that penetrate the Earth's ionosphere, observations in extremely "radio quiet" locations such as the Moon's far side, or both. We describe a series of lunar-based radio wavelength interferometers of increasing capability. The Radio Observatory for Lunar Sortie Science (ROLSS) is an array designed to be deployed during the first lunar sorties (or even before via robotic rovers) and addressing particle acceleration and the lunar ionosphere. Future arrays would be larger, more capable, and deployed as experience is gained in working on the lunar surface.

  7. Short-Term Energy Outlook Supplement: Status of Libyan Loading Ports and Oil and Natural Gas Fields

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9 SeptemberSetting theSheldonOctoberOutlookShort-Term

  8. Sandia National Laboratories: Wavelength Conversion Materials

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

    TechnologiesWavelength Conversion Materials Wavelength Conversion Materials Overview of SSL Wavelength Conversion Materials Rare-Earth Phosphors Inorganic phosphors doped with...

  9. Ultra-short wavelength x-ray system

    DOE Patents [OSTI]

    Umstadter, Donald (Ann Arbor, MI); He, Fei (Ann Arbor, MI); Lau, Yue-Ying (Potomac, MD)

    2008-01-22T23:59:59.000Z

    A method and apparatus to generate a beam of coherent light including x-rays or XUV by colliding a high-intensity laser pulse with an electron beam that is accelerated by a synchronized laser pulse. Applications include x-ray and EUV lithography, protein structural analysis, plasma diagnostics, x-ray diffraction, crack analysis, non-destructive testing, surface science and ultrafast science.

  10. Non-linear modulation of short wavelength compressional Alfven eigenmodes

    SciTech Connect (OSTI)

    Fredrickson, E. D.; Gorelenkov, N. N.; Podesta, M.; Gerhardt, S. P.; Bell, R. E.; Diallo, A.; LeBlanc, B. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States); Bortolon, A. [University of California, Irvine, California 92697 (United States); Crocker, N. A. [University of California, Los Angeles, California 90095 (United States); Levinton, F. M.; Yuh, H. [Nova Photonics, Princeton, New Jersey 08543 (United States)

    2013-04-15T23:59:59.000Z

    Most Alfvenic activity in the frequency range between toroidal Alfven eigenmodes and roughly one half of the ion cyclotron frequency on National Spherical Torus eXperiment [Ono et al., Nucl. Fusion 40, 557 (2000)], that is, approximately 0.3 MHz up to Almost-Equal-To 1.2 MHz, are modes propagating counter to the neutral beam ions. These have been modeled as Compressional and Global Alfven Eigenmodes (CAE and GAE) and are excited through a Doppler-shifted cyclotron resonance with the beam ions. There is also a class of co-propagating modes at higher frequency than the counter-propagating CAE and GAE. These modes have been identified as CAE, and are seen mostly in the company of a low frequency, n = 1 kink-like mode. In this paper, we present measurements of the spectrum of these high frequency CAE (hfCAE) and their mode structure. We compare those measurements to a simple model of CAE and present a predator-prey type model of the curious non-linear coupling of the hfCAE and the low frequency kink-like mode.

  11. Nonlinear photoemission from metal surfaces induced by short laser pulses: the effect of field enhancement by surface plasmons

    E-Print Network [OSTI]

    Sandor Varro; Norbert Kroo

    2013-01-09T23:59:59.000Z

    Nonlinear electron emission processes induced by surface plasmon oscillations have been studied both experimentally and theoretically. The measured above-threshold electron spectra extend up to energies whose appearance cannot be explained solely by standard non-perturbative methods, which predict photon energy separated discrete energy line spectra with the known fast fall - plateau - cutoff envelope shape, even when taking the large field enhancement into account. The theoretical analysis of our data, based on the concept of plasmon-induced near-field effects, gives reasonably good explanation and qualitative agreement in the whole intensity range.

  12. Sandia Energy - Wavelength Conversion Materials

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

    to a wider range of wavelengths in this region. Phosphors based on divalent europium (Eu+2) are available in the green and even into the blue emission region. Photon...

  13. The long wavelength limit of hard thermal loop effective actions

    E-Print Network [OSTI]

    F T Brandt; J Frenkel; J C Taylor

    2009-01-22T23:59:59.000Z

    We derive a closed form expression for the long wavelength limit of the effective action for hard thermal loops in an external gravitational field. It is a function of the metric, independent of time derivatives. It is compared and contrasted with the static limit, and with the corresponding limits in an external Yang-Mills field.

  14. Analysis of a spinning polygon wavelength swept laser

    E-Print Network [OSTI]

    Johnson, Bart; Kuznetsov, Mark; Goldberg, Brian D; Whitney, Peter; Flanders, Dale C

    2015-01-01T23:59:59.000Z

    It has been known for quite some time that spinning polygon, and similar, swept lasers used in OCT favor the short to long wavelength sweep direction because of four wave mixing in the gain medium. Here we have reformulated the problem in the time domain and show experimentally and through numerical simulation that these lasers are pulsed. The emitted pulses modulate the gain medium refractive index to red shift the light. Instead of new wavelengths being built up slowly from spontaneous emission, each pulse hops to a longer wavelength by nonlinear means, tracking the tunable filter. This allows high speed, low noise tuning in the blue to red direction. Based on this model, we make the first coherence length calculations for a swept source.

  15. Wavelength calibration of the JWST-MIRI medium resolution spectrometer

    E-Print Network [OSTI]

    Martinez-Galarza, J R; Hernan-Caballero, A; Azzollini, R; Glasse, A; Kendrew, S; Brandl, B; Lahuis, F

    2010-01-01T23:59:59.000Z

    We present the wavelength and spectral resolution characterisation of the Integral Field Unit (IFU) Medium Resolution Spectrometer for the Mid-InfraRed Instrument (MIRI), to fly onboard the James Webb Space Telescope in 2014. We use data collected using the Verification Model of the instrument and develop an empirical method to calibrate properties such as wavelength range and resolving power in a portion of the spectrometer's full spectral range (5-28 microns). We test our results against optical models to verify the system requirements and combine them with a study of the fringing pattern in the instrument's detector to provide a more accurate calibration. We show that MIRI's IFU spectrometer will be able to produce spectra with a resolving power above R=2800 in the wavelength range 6.46-7.70 microns, and that the unresolved spectral lines are well fitted by a Gaussian profile.

  16. Field performance of 'populus' in short-rotation intensive culture plantations in the north-central US Forest Service research paper

    SciTech Connect (OSTI)

    Hansen, E.A.; Ostry, M.E.; Johnson, W.D.; Tolsted, D.N.; Netzer, D.A.

    1994-01-01T23:59:59.000Z

    The report describes a network of short-rotation Populus research and demonstration plantations that has been established across a 5-State region in the north-central U.S. to identify suitable hybrid poplar clones for large-scale biomass plantations in the region. Reports 6-year results.

  17. Multi-Wavelength Image Space: Another Grid-Enabled Science Roy Williams 1

    E-Print Network [OSTI]

    Deelman, Ewa

    the wavelengths. In this paper, we consider a new paradigm for mining knowledge from the images of the sky surveys multi- wavelength images. To see sky images in the same pixel space, they must be projected will describe both scientific goals, and also how grid computing can open this new field. The term multi

  18. Multi-Wavelength Image Space: Another Grid-Enabled Science Roy Williams1

    E-Print Network [OSTI]

    Williams, Roy

    paradigm for mining knowledge from the images of the sky surveys: by federating the images directly We describe a new Grid-enabled branch of astronomy: multi-wavelength images. To see sky images-wavelength image. We will describe both scientific goals, and also how grid computing can open this new field

  19. Wavelength-doubling optical parametric oscillator

    DOE Patents [OSTI]

    Armstrong, Darrell J. (Albuquerque, NM); Smith, Arlee V. (Albuquerque, NM)

    2007-07-24T23:59:59.000Z

    A wavelength-doubling optical parametric oscillator (OPO) comprising a type II nonlinear optical medium for generating a pair of degenerate waves at twice a pump wavelength and a plurality of mirrors for rotating the polarization of one wave by 90 degrees to produce a wavelength-doubled beam with an increased output energy by coupling both of the degenerate waves out of the OPO cavity through the same output coupler following polarization rotation of one of the degenerate waves.

  20. Optical sensing based on wavelength modulation spectroscopy

    DOE Patents [OSTI]

    Buckley, Steven G. (Redmond, WA); Gharavi, Mohammadreza (Tehran, IR); Borchers; Marco (Berlin, DE)

    2011-06-28T23:59:59.000Z

    Techniques, apparatus and systems for using Wavelength Modulation Spectroscopy measurements to optically monitor gas media such as gases in gas combustion chambers.

  1. Long pulse production from short pulses

    DOE Patents [OSTI]

    Toeppen, John S. (Livermore, CA)

    1994-01-01T23:59:59.000Z

    A method of producing a long output pulse (SA) from a short pump pulse (P), using an elongated amplified fiber (11) having a doped core (12) that provides an amplifying medium for light of one color when driven into an excited state by light of a shorter wavelength and a surrounding cladding 13. A seed beam (S) of the longer wavelength is injected into the core (12) at one end of the fiber (11) and a pump pulse (P) of the shorter wavelength is injected into the cladding (13) at the other end of the fiber (11). The counter-propagating seed beam (S) and pump pulse (P) will produce an amplified output pulse (SA) having a time duration equal to twice the transit time of the pump pulse (P) through the fiber (11) plus the length of the pump pulse (P).

  2. Long pulse production from short pulses

    DOE Patents [OSTI]

    Toeppen, J.S.

    1994-08-02T23:59:59.000Z

    A method of producing a long output pulse from a short pump pulse is disclosed, using an elongated amplified fiber having a doped core that provides an amplifying medium for light of one color when driven into an excited state by light of a shorter wavelength and a surrounding cladding. A seed beam of the longer wavelength is injected into the core at one end of the fiber and a pump pulse of the shorter wavelength is injected into the cladding at the other end of the fiber. The counter-propagating seed beam and pump pulse will produce an amplified output pulse having a time duration equal to twice the transit time of the pump pulse through the fiber plus the length of the pump pulse. 3 figs.

  3. Wavelength Determination for Solar Features Observed by the EUV Imaging Spectrometer on Hinode

    SciTech Connect (OSTI)

    Brown,C.; Hara, H.; Kamio, S.; Feldman, U.; Seely, J.; Doschek, G.; Mariska, J.; Korendyke, C.; Lang, J.; Dere, K.

    2007-01-01T23:59:59.000Z

    A wavelength calibration of solar lines observed by the high resolution EUV Imaging Spectrometer (EIS) on the Hinode satellite is reported. Spectral features of the quiet sun and of two mildly active areas were measured and calibrated. A listing of the stronger observed lines with identification of the leading contributor ions is presented. 41 lines are reported, with 90% identified. Wavelength precisions (2{sigma}) of {+-}0.0031 Angstroms for the EIS short band and {+-}0.0029 Angstroms for the EIS long band are obtained. These lines, typical of 1-2x10{sup 6} K plasmas, are recommended as standards for the establishment of EIS wavelength scales. The temperature of EIS varies by about 1.5 C around the orbit and also with spacecraft pointing. The correlation of these temperature changes with wavelength versus pixel number scale changes is reported.

  4. Semiconductor laser with multiple lasing wavelengths

    DOE Patents [OSTI]

    Fischer, Arthur J.; Choquette, Kent D.; Chow, Weng W.

    2003-07-29T23:59:59.000Z

    A new class of multi-terminal vertical-cavity semiconductor laser components has been developed. These multi-terminal laser components can be switched, either electrically or optically, between distinct lasing wavelengths, or can be made to lase simultaneously at multiple wavelengths.

  5. Atomic intermixing and interface roughness in short-period InAs/GaSb superlattices for infrared photodetectors

    SciTech Connect (OSTI)

    Ashuach, Y.; Lakin, E.; Kaufmann, Y. [Department of Materials Science and Engineering, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Saguy, C. [Solid State Institute, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Zolotoyabko, E., E-mail: zloto@tx.technion.ac.il [Department of Materials Science and Engineering, Technion—Israel Institute of Technology, Haifa 32000 (Israel); Solid State Institute, Technion—Israel Institute of Technology, Haifa 32000 (Israel)

    2014-09-28T23:59:59.000Z

    A set of advanced characterization methods, including high-resolution X-ray diffraction (measurements and simulations), cross-sectional scanning tunneling microscopy, and high-angle annular dark-field scanning transmission electron microscopy is applied to quantify the interface roughness and atomic intermixing (in both cation and anion sub-lattices) in short period (6–7?nm) InAs/GaSb superlattices intended for mid-wavelength (M) and long-wavelength (L) infrared detectors. The undesired atomic intermixing and interface roughness in the L-samples were found to be considerably lower than in the M-samples. In all specimens, anion intermixing is much higher than that in the cation sub-lattice. Possible origins of these findings are discussed.

  6. Optical amplification at the 1. 31 wavelength

    DOE Patents [OSTI]

    Cockroft, N.J.

    1994-02-15T23:59:59.000Z

    An optical amplifier operating at the 1.31 [mu]m wavelength for use in such applications as telecommunications, cable television, and computer systems is described. An optical fiber or other waveguide device is doped with both Tm[sup 3+] and Pr[sup 3+] ions. When pumped by a diode laser operating at a wavelength of 785 nm, energy is transferred from the Tm[sup 3+] ions to the Pr[sup 3+] ions, causing the Pr[sup 3+] ions to amplify at a wavelength of 1.31. 1 figure.

  7. Diminished Short Channel Effects in Nanoscale Double-Gate Silicon-on-Insulator MetalOxideSemiconductor Field-Effect-Transistors

    E-Print Network [OSTI]

    Kumar, M. Jagadesh

    ) and the back-gate oxide (tb) thickness is 2 nm. The doping in the p-type body and n+ source/drain regions­Oxide­Semiconductor Field-Effect-Transistors due to Induced Back-Gate Step Potential M. Jagadesh KUMAR Ã and G. Venkateshwar surface potential profile at the back gate of an asymmetrical double gate (DG) silicon-on-insulator (SOI

  8. Semiconductor light source with electrically tunable emission wavelength

    DOE Patents [OSTI]

    Belenky, Gregory (Port Jefferson, NY); Bruno, John D. (Bowie, MD); Kisin, Mikhail V. (Centereach, NY); Luryi, Serge (Setauket, NY); Shterengas, Leon (Centereach, NY); Suchalkin, Sergey (Centereach, NY); Tober, Richard L. (Elkridge, MD)

    2011-01-25T23:59:59.000Z

    A semiconductor light source comprises a substrate, lower and upper claddings, a waveguide region with imbedded active area, and electrical contacts to provide voltage necessary for the wavelength tuning. The active region includes single or several heterojunction periods sandwiched between charge accumulation layers. Each of the active region periods comprises higher and lower affinity semiconductor layers with type-II band alignment. The charge carrier accumulation in the charge accumulation layers results in electric field build-up and leads to the formation of generally triangular electron and hole potential wells in the higher and lower affinity layers. Nonequillibrium carriers can be created in the active region by means of electrical injection or optical pumping. The ground state energy in the triangular wells and the radiation wavelength can be tuned by changing the voltage drop across the active region.

  9. Apparatus for shifting the wavelength of light

    DOE Patents [OSTI]

    McCulla, William H. (Oak Ridge, TN); Allen, Jr., John D. (Knoxville, TN)

    1983-01-01T23:59:59.000Z

    A light beam is reflected back and forth between a rotating body having a retroreflection corner at opposite ends thereof and a fixed mirror to change the wavelength of the light beam by the Doppler effect.

  10. Sandia National Laboratories: Wavelength Conversion Materials

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

    because of the steep drop-off in human eye sensitivity at longer wavelength) and absorption in the near-UV or blue region has been difficult to achieve. Broader-band...

  11. Magnet Coil Shorted Turn Detector

    SciTech Connect (OSTI)

    Dinkel, J.A.; Biggs, J.E.

    1994-03-01T23:59:59.000Z

    The Magnet Coil Shorted Turn Detector has been developed to facilitate the location of shorted turns in magnet coils. Finding these shorted turns is necessary to determine failure modes that are a necessary step in developing future production techniques. Up to this point, coils with shorted turns had the insulation burned off without the fault having been located. This disassembly process destroyed any chance of being able to find the fault. In order to maintain a flux balance in a coupled system such as a magnet coil, the current in a shorted turn must be opposed to the incident current. If the direction of the current in each conductor can be measured relative to the incident current, then the exact location of the short can be determined. In this device, an AC voltage is applied to the magnet under test. A small hand held B-dot pickup coil monitors the magnetic field produced by current in the individual magnet conductors. The relative phase of this pickup coil voltage is compared to a reference signal derived from the input current to detect a current reversal as the B-dot pickup coil is swept over the conductors of the coil under test. This technique however, is limited to only those conductors that are accessible to the hand held probe.

  12. Switchable wavelength-selective and diffuse metamaterial absorber/emitter with a phase transition spacer layer

    SciTech Connect (OSTI)

    Wang, Hao; Yang, Yue; Wang, Liping, E-mail: liping.wang@asu.edu [School for Engineering of Matter, Transport and Energy, Arizona State University, Tempe, Arizona 85287 (United States)

    2014-08-18T23:59:59.000Z

    We numerically demonstrate a switchable metamaterial absorber/emitter by thermally turning on or off the excitation of magnetic resonance upon the phase transition of vanadium dioxide (VO{sub 2}). Perfect absorption peak exists around the wavelength of 5??m when the excitation of magnetic resonance is supported with the insulating VO{sub 2} spacer layer. The wavelength-selective absorption is switched off when the magnetic resonance is disabled with metallic VO{sub 2} that shorts the top and bottom metallic structures. The resonance wavelength can be tuned with different geometry, and the switchable metamaterial exhibits diffuse behaviors at oblique angles. The results would facilitate the design of switchable metamaterials for active control in energy and sensing applications.

  13. Device for wavelength-selective imaging

    DOE Patents [OSTI]

    Frangioni, John V. (Wayland, MA)

    2010-09-14T23:59:59.000Z

    An imaging device captures both a visible light image and a diagnostic image, the diagnostic image corresponding to emissions from an imaging medium within the object. The visible light image (which may be color or grayscale) and the diagnostic image may be superimposed to display regions of diagnostic significance within a visible light image. A number of imaging media may be used according to an intended application for the imaging device, and an imaging medium may have wavelengths above, below, or within the visible light spectrum. The devices described herein may be advantageously packaged within a single integrated device or other solid state device, and/or employed in an integrated, single-camera medical imaging system, as well as many non-medical imaging systems that would benefit from simultaneous capture of visible-light wavelength images along with images at other wavelengths.

  14. Two-wavelength spatial-heterodyne holography

    DOE Patents [OSTI]

    Hanson, Gregory R. (Clinton, TN); Bingham, Philip R. (Knoxville, TN); Simpson, John T. (Knoxville, TN); Karnowski, Thomas P. (Knoxville, TN); Voelkl, Edgar (Austin, TX)

    2007-12-25T23:59:59.000Z

    Systems and methods are described for obtaining two-wavelength differential-phase holograms. A method includes determining a difference between a filtered analyzed recorded first spatially heterodyne hologram phase and a filtered analyzed recorded second spatially-heterodyned hologram phase.

  15. Field Theory and Standard Model

    E-Print Network [OSTI]

    W. Buchmüller; C. Lüdeling

    2006-09-18T23:59:59.000Z

    This is a short introduction to the Standard Model and the underlying concepts of quantum field theory.

  16. SHORT-WAVELENGTH TECHNOLOGY AND THE POTENTIAL FOR DISTRIBUTED NETWORKS OF SMALL RADAR SYSTEMS

    E-Print Network [OSTI]

    Droegemeier, Kelvin K.

    Bharadwajb , Yanting Wangb , Eric Lyonsa , Kurt Hondle , Yuxiang Liub , Eric Knappa , Ming Xuec , Anthony, Amherst, MA 01003 b. Colorado State University, Fort Collins, CO 80523 c. University of Oklahoma, Norman, and rapid-update (tens of seconds) observations extending from the boundary layer up to the tops of storms

  17. Amplified short-wavelength light scattered by relativistic electrons in the laser-induced optical lattice

    E-Print Network [OSTI]

    Andriyash, I A; Malka, V; d'Humières, E; Balcou, Ph

    2014-01-01T23:59:59.000Z

    The scheme of the XUV/X-ray free electron laser based on the optical undulator created by two overlapped transverse laser beams is analyzed. A kinetic theoretical description and an ad hoc numerical model are developed to account for the finite energy spread, angular divergence and the spectral properties of the electron beam in the optical lattice. The theoretical findings are compared to the results of the one- and three-dimensional numerical modeling with the spectral free electron laser code PLARES.

  18. Short-wavelength upconversion emissions in codoped glass ceramic and the optical

    E-Print Network [OSTI]

    Cao, Wenwu

    of electrical engineering, Yanshan University, Qinhuangdao, 066004, China 3 Laboratory of Sono- and photo. In addition, an optical temperature sensor based on the blue upconversion emissions from 5 F2,3/3 K85 I8 and 5 ceramic be a promising candidate for sensitive optical temperature sensor with high resolution and good

  19. Phase contrast imaging measurements and modeling of short wavelength turbulence in the DIII-D tokamak

    E-Print Network [OSTI]

    Dorris, James Robert, III

    2010-01-01T23:59:59.000Z

    The DIII-D phase contrast imaging (PCI) diagnostic has been upgraded and used to measure turbulence in the outer plasma region (0.7 < r/a < 1). These upgrades extended its operational range to high frequencies (10 kHz - ...

  20. WAVELENGTH CALIBRATION OF THE HAMILTON ECHELLE SPECTROGRAPH

    SciTech Connect (OSTI)

    Pakhomov, Yu. V. [Institute of Astronomy, Russian Academy of Sciences, Moscow (Russian Federation); Zhao, G., E-mail: pakhomov@inasan.ru [Key Laboratory of Optical Astronomy, National Astronomical Observatories, Chinese Academy of Sciences, Beijing 100012 (China)

    2013-10-01T23:59:59.000Z

    We present the wavelength calibration of the Hamilton Echelle Spectrograph at Lick Observatory. The main problem with the calibration of this spectrograph arises from the fact that thorium lines are absent in the spectrum of the presumed ThAr hollow-cathode lamp now under operation; numerous unknown strong lines, which have been identified as titanium lines, are present in the spectrum. We estimate the temperature of the lamp's gas which permits us to calculate the intensities of the lines and to select a large number of relevant Ti I and Ti II lines. The resulting titanium line list for the Lick hollow-cathode lamp is presented. The wavelength calibration using this line list was made with an accuracy of about 0.006 Å.

  1. Wavelength meter having single mode fiber optics multiplexed inputs

    DOE Patents [OSTI]

    Hackel, Richard P. (Livermore, CA); Paris, Robert D. (San Ramon, CA); Feldman, Mark (Pleasanton, CA)

    1993-01-01T23:59:59.000Z

    A wavelength meter having a single mode fiber optics input is disclosed. The single mode fiber enables a plurality of laser beams to be multiplexed to form a multiplexed input to the wavelength meter. The wavelength meter can provide a determination of the wavelength of any one or all of the plurality of laser beams by suitable processing. Another aspect of the present invention is that one of the laser beams could be a known reference laser having a predetermined wavelength. Hence, the improved wavelength meter can provide an on-line calibration capability with the reference laser input as one of the plurality of laser beams.

  2. Wavelength meter having single mode fiber optics multiplexed inputs

    DOE Patents [OSTI]

    Hackel, R.P.; Paris, R.D.; Feldman, M.

    1993-02-23T23:59:59.000Z

    A wavelength meter having a single mode fiber optics input is disclosed. The single mode fiber enables a plurality of laser beams to be multiplexed to form a multiplexed input to the wavelength meter. The wavelength meter can provide a determination of the wavelength of any one or all of the plurality of laser beams by suitable processing. Another aspect of the present invention is that one of the laser beams could be a known reference laser having a predetermined wavelength. Hence, the improved wavelength meter can provide an on-line calibration capability with the reference laser input as one of the plurality of laser beams.

  3. CONFIRMING THE PRIMARILY SMOOTH STRUCTURE OF THE VEGA DEBRIS DISK AT MILLIMETER WAVELENGTHS

    SciTech Connect (OSTI)

    Hughes, A. Meredith; Plambeck, Richard; Chiang, Eugene [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Wilner, David J.; Andrews, Sean M. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Mason, Brian [National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475 (United States); Carpenter, John M. [California Institute of Technology, Department of Astronomy, MC 105-24, Pasadena, CA 91125 (United States); Chiang, Hsin-Fang [Institute for Astronomy, University of Hawaii, 640 North Aohoku Place, Hilo, HI 96720 (United States); Williams, Jonathan P. [Institute for Astronomy, University of Hawaii, 2680 Woodlawn Drive, Honolulu, HI 96822 (United States); Hales, Antonio [Joint ALMA Observatory, Av. El Golf 40, Piso 18, Santiago (Chile); Su, Kate [Steward Observatory, University of Arizona, 933 North Cherry Avenue, Tucson, AZ 85721 (United States); Dicker, Simon; Korngut, Phil; Devlin, Mark, E-mail: mhughes@astro.berkeley.edu [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States)

    2012-05-01T23:59:59.000Z

    Clumpy structure in the debris disk around Vega has been previously reported at millimeter wavelengths and attributed to concentrations of dust grains trapped in resonances with an unseen planet. However, recent imaging at similar wavelengths with higher sensitivity has disputed the observed structure. We present three new millimeter-wavelength observations that help to resolve the puzzling and contradictory observations. We have observed the Vega system with the Submillimeter Array (SMA) at a wavelength of 880 {mu}m and an angular resolution of 5''; with the Combined Array for Research in Millimeter-wave Astronomy (CARMA) at a wavelength of 1.3 mm and an angular resolution of 5''; and with the Green Bank Telescope (GBT) at a wavelength of 3.3 mm and angular resolution of 10''. Despite high sensitivity and short baselines, we do not detect the Vega debris disk in either of the interferometric data sets (SMA and CARMA), which should be sensitive at high significance to clumpy structure based on previously reported observations. We obtain a marginal (3{sigma}) detection of disk emission in the GBT data; the spatial distribution of the emission is not well constrained. We analyze the observations in the context of several different models, demonstrating that the observations are consistent with a smooth, broad, axisymmetric disk with inner radius 20-100 AU and width {approx}> 50 AU. The interferometric data require that at least half of the 860 {mu}m emission detected by previous single-dish observations with the James Clerk Maxwell Telescope be distributed axisymmetrically, ruling out strong contributions from flux concentrations on spatial scales of {approx}<100 AU. These observations support recent results from the Plateau de Bure Interferometer indicating that previous detections of clumpy structure in the Vega debris disk were spurious.

  4. Influence of Adsorption Site and Wavelength on the Photodesorption...

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

    Adsorption Site and Wavelength on the Photodesorption of NO from the (Fe,Cr)3O4(111) Mixed Oxide Surface. Influence of Adsorption Site and Wavelength on the Photodesorption of NO...

  5. Wavelength tunable source of subpicosecond pulses from CW passively mode-locked two-section multiple-quantum-well laser

    SciTech Connect (OSTI)

    Salvatore, R.A.; Schrans, T.; Yariv, A. (California Inst. of Tech., Pasadena, CA (United States). Dept. of Applied Physics)

    1993-07-01T23:59:59.000Z

    A wavelength tunable passively mode-locked semi-conductor laser source of subpicosecond pulses is demonstrated. The system includes a two-section multiple-quantum-well laser which is coupled to an external grating for tuning and is followed by an external grating pair for pulse compression. A tuning range of 16 nm around 846 nm is obtained, resulting in compressed pulse widths as short as 260 fs and pulse widths shorter than 600 fs for all wavelength values within this tuning range. Time bandwidth products are one to two times the transform limit.

  6. Investigation of the Faraday Rotation Measure and Magnetic Field Structures of Several AGN Jets on Sub-Parsec to Parsec Scales

    E-Print Network [OSTI]

    Shane P. O'Sullivan; Denise C. Gabuzda

    2007-09-30T23:59:59.000Z

    Preliminary VLBA polarisation results on 6 ``blazars'' from 6.5-cm to 7-mm are presented here. Observing at several different wavelengths, separated by short and long intervals, enabled reliable information about the magnetic (B) field structure to be obtained and for the effect of Faraday Rotation to be determined and corrected. For all sources the magnitude of the core Rotation Measure (RM) derived from the shorter wavelength data was greater than that derived from the longer wavelength data, consistent with a higher electron density and/or B-field strength closer to the central engine. A transverse RM gradient was detected in the jet of 0954+658, providing evidence for the presence of a helical B-field surrounding the jet. The RM in the core region of 2200+420 (BL Lac) displays sign changes in different wavelength intervals (on different spatial scales); we suggest an explanation for this in terms of modest bends in a helical B-field surrounding the jet.

  7. Excitation wavelength dependent photoluminescence in structurally non-uniform Si/SiGe-island heteroepitxial multilayers

    SciTech Connect (OSTI)

    Modi, N.; Tsybeskov, L. [Department of Electrical and Computer Engineering, New Jersey Institute of Technology, Newark, New Jersey 07102 (United States); Lockwood, D. J.; Wu, X.; Baribeau, J.-M. [Institute for Microstructural Sciences, National Research Council, Ottawa, Ontario K1A 0R6 (Canada)

    2012-06-01T23:59:59.000Z

    In nanometer-size Si/SiGe-island heteroepitxial multilayers grown on Si(001), low temperature photoluminescence spectra are observed that strongly depend on the excitation wavelength and show a strong correlation with structural properties revealed by transmission electron microscopy. These experimental results can be explained by assuming that the optically created carriers are strongly localized at Si/SiGe island heterointerfaces. We show that electron-hole pairs are generated and recombine within spatial regions mainly defined by the photoexcitation penetration depth, and that the estimated exciton diffusion length is notably short and comparable with the SiGe-island average size.

  8. SHORT REVIEW Ecological genomics: understanding gene and

    E-Print Network [OSTI]

    Kaufman, Glennis A.

    SHORT REVIEW Ecological genomics: understanding gene and genome function in the natural environment MC Ungerer, LC Johnson and MA Herman Division of Biology, Ecological Genomics Institute, Kansas State University, Manhattan, KS, USA The field of ecological genomics seeks to understand the genetic mechanisms

  9. Provably Good Solutions for Wavelength Assignment in Optical ...

    E-Print Network [OSTI]

    In this paper, we study the minimum converter wavelength assignment problem in .... like linear programming based branch-and-bound on the assignment ...

  10. Wavelength Assignment in Multi-Fiber WDM Networks by ...

    E-Print Network [OSTI]

    In this paper, we study wavelength assignment problems in multi-fiber WDM net- ... A comparison with linear programming lower bounds reveals that the bounds ...

  11. Visible-wavelength semiconductor lasers and arrays

    DOE Patents [OSTI]

    Schneider, Jr., Richard P. (Albuquerque, NM); Crawford, Mary H. (Albuquerque, NM)

    1996-01-01T23:59:59.000Z

    A visible semiconductor laser. The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1.lambda.) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%.

  12. Visible-wavelength semiconductor lasers and arrays

    DOE Patents [OSTI]

    Schneider, R.P. Jr.; Crawford, M.H.

    1996-09-17T23:59:59.000Z

    The visible semiconductor laser includes an InAlGaP active region surrounded by one or more AlGaAs layers on each side, with carbon as the sole p-type dopant. Embodiments of the invention are provided as vertical-cavity surface-emitting lasers (VCSELs) and as edge-emitting lasers (EELs). One or more transition layers comprised of a substantially indium-free semiconductor alloy such as AlAsP, AlGaAsP, or the like may be provided between the InAlGaP active region and the AlGaAS DBR mirrors or confinement layers to improve carrier injection and device efficiency by reducing any band offsets. Visible VCSEL devices fabricated according to the invention with a one-wavelength-thick (1{lambda}) optical cavity operate continuous-wave (cw) with lasing output powers up to 8 mW, and a peak power conversion efficiency of up to 11%. 5 figs.

  13. Photoemission electron microscopy of localized surface plasmons in silver nanostructures at telecommunication wavelengths

    E-Print Network [OSTI]

    Mårsell, Erik; Arnold, Cord L; Xu, Hongxing; Mauritsson, Johan; Mikkelsen, Anders

    2015-01-01T23:59:59.000Z

    We image the field enhancement at Ag nanostructures using femtosecond laser pulses with a center wavelength of 1.55 micrometer. Imaging is based on non-linear photoemission observed in a photoemission electron microscope (PEEM). The images are directly compared to ultra violet PEEM and scanning electron microscopy (SEM) imaging of the same structures. Further, we have carried out atomic scale scanning tunneling microscopy (STM) on the same type of Ag nanostructures and on the Au substrate. Measuring the photoelectron spectrum from individual Ag particles shows a larger contribution from higher order photoemission process above the work function threshold than would be predicted by a fully perturbative model, consistent with recent results using shorter wavelengths. Investigating a wide selection of both Ag nanoparticles and nanowires, field enhancement is observed from 30% of the Ag nanoparticles and from none of the nanowires. No laser-induced damage is observed of the nanostructures neither during the PEEM ...

  14. The Stability of Magnetized Rotating Plasmas with Superthermal Fields

    E-Print Network [OSTI]

    Martin E. Pessah; Dimitrios Psaltis

    2005-04-13T23:59:59.000Z

    During the last decade it has become evident that the magnetorotational instability is at the heart of the enhanced angular momentum transport in weakly magnetized accretion disks around neutron stars and black holes. In this paper, we investigate the local linear stability of differentially rotating, magnetized flows and the evolution of the magnetorotational instability beyond the weak-field limit. We show that, when superthermal toroidal fields are considered, the effects of both compressibility and magnetic tension forces, which are related to the curvature of toroidal field lines, should be taken fully into account. We demonstrate that the presence of a strong toroidal component in the magnetic field plays a non-trivial role. When strong fields are considered, the strength of the toroidal magnetic field not only modifies the growth rates of the unstable modes but also determines which modes are subject to instabilities. We find that, for rotating configurations with Keplerian laws, the magnetorotational instability is stabilized at low wavenumbers for toroidal Alfven speeds exceeding the geometric mean of the sound speed and the rotational speed. We discuss the significance of our findings for the stability of cold, magnetically dominated, rotating fluids and argue that, for these systems, the curvature of toroidal field lines cannot be neglected even when short wavelength perturbations are considered. We also comment on the implications of our results for the validity of shearing box simulations in which superthermal toroidal fields are generated.

  15. Systematic wavelength selection for improved multivariate spectral analysis

    DOE Patents [OSTI]

    Thomas, Edward V. (2828 Georgia NE., Albuquerque, NM 87110); Robinson, Mark R. (1603 Solano NE., Albuquerque, NM 87110); Haaland, David M. (809 Richmond Dr. SE., Albuquerque, NM 87106)

    1995-01-01T23:59:59.000Z

    Methods and apparatus for determining in a biological material one or more unknown values of at least one known characteristic (e.g. the concentration of an analyte such as glucose in blood or the concentration of one or more blood gas parameters) with a model based on a set of samples with known values of the known characteristics and a multivariate algorithm using several wavelength subsets. The method includes selecting multiple wavelength subsets, from the electromagnetic spectral region appropriate for determining the known characteristic, for use by an algorithm wherein the selection of wavelength subsets improves the model's fitness of the determination for the unknown values of the known characteristic. The selection process utilizes multivariate search methods that select both predictive and synergistic wavelengths within the range of wavelengths utilized. The fitness of the wavelength subsets is determined by the fitness function F=.function.(cost, performance). The method includes the steps of: (1) using one or more applications of a genetic algorithm to produce one or more count spectra, with multiple count spectra then combined to produce a combined count spectrum; (2) smoothing the count spectrum; (3) selecting a threshold count from a count spectrum to select these wavelength subsets which optimize the fitness function; and (4) eliminating a portion of the selected wavelength subsets. The determination of the unknown values can be made: (1) noninvasively and in vivo; (2) invasively and in vivo; or (3) in vitro.

  16. Short Baseline Neutrino Oscillation Experiments

    E-Print Network [OSTI]

    Katori, Teppei

    2014-01-01T23:59:59.000Z

    Series of short baseline neutrino oscillation experiments provided unexpected results, and now they are called short baseline anomalies, and all indicates an existence of sterile neutrinos with a mass scale around 1~eV. The signals of short baseline anomalies are reported from 4 different classes of experiments. However, at this moment, there is no convincing theoretical model to explain such sterile neutrinos, and a single experiment to confirm 1~eV sterile neutrinos may be challenging. In this short note, we describe classes of short baseline neutrino oscillation experiments and their goals.

  17. Subthreshold pair production in short laser pulses

    E-Print Network [OSTI]

    T. Nousch; D. Seipt; B. Kampfer; A. I. Titov

    2012-06-01T23:59:59.000Z

    The $e^+e^-$ pair production by a probe photon traversing a linearly polarized laser pulse is treated as generalized nonlinear Breit-Wheeler process. For short laser pulses with very few oscillations of the electromagnetic field we find below the perturbative weak-field threshold $\\sqrt{s} = 2m$ a similar enhancement of the pair production rate as for circular polarization. The strong subthreshold enhancement is traced back to the finite bandwidth of the laser pulse. A folding model is developed which accounts for the interplay of the frequency spectrum and the intensity distribution in the course of the pulse.

  18. Digitized dual wavelength radar data from a Texas thunderstorm

    E-Print Network [OSTI]

    Radlein, Robin Ann

    1977-01-01T23:59:59.000Z

    DIGITIZED DUAL WAVL'LENGTH RADAR DATA FROM A TEXAS THUNDERSTORM A Thesis ROBIN ANN RADLEIN Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree ol MASTER OF SCIENCE December 1977... Wavelength Radar Data from a Texas Thunderstorm. (December 1977) Robin Ann Radlein~ B. S , Texas ASN University Chairman of Advisory Committee: Dr Vance Noyer Nulti-tilt digitized dual wavelength radar data collected during a Texas thunderstorm were...

  19. Fast quantum dot single photon source triggered at telecommunications wavelength

    E-Print Network [OSTI]

    Kelley Rivoire; Sonia Buckley; Arka Majumdar; Hyochul Kim; Pierre Petroff; Jelena Vuckovic

    2010-12-20T23:59:59.000Z

    We demonstrate a quantum dot single photon source at 900 nm triggered at 300 MHz by a continuous wave telecommunications wavelength laser followed by an electro-optic modulator. The quantum dot is excited by on-chip-generated second harmonic radiation, resonantly enhanced by a GaAs photonic crystal cavity surrounding the InAs quantum dot. Our result suggests a path toward the realization of telecommunications-wavelength-compatible quantum dot single photon sources with speeds exceeding 1 GHz.

  20. Stability of Wavelengths and Spatiotemporal Intermittency in Coupled Map Lattices

    E-Print Network [OSTI]

    A. Lambert; R. Lima

    1994-08-01T23:59:59.000Z

    In relation to spatiotemporal intermittency, as it can be observed in coupled map lattices, we study the stability of different wavelengths in competition. Introducing a two dimensional map, we compare its dynamics with the one of the whole lattice. We conclude a good agreement between the two. The reduced model also allows to introduce an order parameter which combines the diffusion parameter and the spatial wavelength under consideration.

  1. Inter-network regions of the Sun at millimetre wavelengths

    E-Print Network [OSTI]

    S. Wedemeyer-Boehm; H. -G. Ludwig; M. Steffen; J. Leenaarts; B. Freytag

    2007-05-18T23:59:59.000Z

    The continuum intensity at wavelengths around 1 mm provides an excellent way to probe the solar chromosphere. Future high-resolution millimetre arrays, such as the Atacama Large Millimeter Array (ALMA), will thus produce valuable input for the ongoing controversy on the thermal structure and the dynamics of this layer. Synthetic brightness temperature maps are calculated on basis of three-dimensional radiation (magneto-)hydrodynamic (MHD) simulations. While the millimetre continuum at 0.3mm originates mainly from the upper photosphere, the longer wavelengths considered here map the low and middle chromosphere. The effective formation height increases generally with wavelength and also from disk-centre towards the solar limb. The average intensity contribution functions are usually rather broad and in some cases they are even double-peaked as there are contributions from hot shock waves and cool post-shock regions in the model chromosphere. Taking into account the deviations from ionisation equilibrium for hydrogen gives a less strong variation of the electron density and with it of the optical depth. The result is a narrower formation height range. The average brightness temperature increases with wavelength and towards the limb. The relative contrast depends on wavelength in the same way as the average intensity but decreases towards the limb. The dependence of the brightness temperature distribution on wavelength and disk-position can be explained with the differences in formation height and the variation of temperature fluctuations with height in the model atmospheres.

  2. The mitigating effect of magnetic fields on Rayleigh-Taylor unstable inertial confinement fusion plasmas

    SciTech Connect (OSTI)

    Srinivasan, Bhuvana; Tang, Xian-Zhu [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2013-05-15T23:59:59.000Z

    Rayleigh-Taylor (RT) instabilities at interfaces of disparate mass densities have long been known to generate magnetic fields during inertial confinement fusion implosions. An externally applied magnetic field can also be efficiently amplified by RT instabilities. The focus here is on magnetic field generation and amplification at the gas-ice interface which is RT unstable during the deceleration phase of the implosion. RT instabilities lead to undesirable mix of hot and cold plasmas which enhances thermal energy loss and tends to produce a more massive warm-spot instead of a hot-spot. Two mechanisms are shown here to mitigate the thermal energy loss from the hot-spot. The first mechanism is the reduction of electron thermal conductivity with interface-aligned magnetic fields. This can occur through self-generated magnetic fields via the Biermann battery effect as well as through externally applied magnetic fields that undergo an exponential growth via the stretch-and-fold magnetohydrodynamic dynamo. Self-generated magnetic fields during RT evolution can result in a factor of 2?10 decrease in the electron thermal conductivity at the gas-ice interface, while externally applied magnetic fields that are compressed to 6–1000 T at the onset of deceleration (corresponding to pre-implosion external fields of 0.06–10 T) could result in a factor of 2–500 reduction in electron thermal conductivity at the gas-ice interface. The second mechanism to mitigate thermal energy loss from the hot-spot is to decrease the interface mixing area between the hot and cold plasmas. This is achieved through large external magnetic fields of 1000 T at the onset of deceleration which damp short-wavelength RT modes and long-wavelength Kelvin-Helmholtz modes thus significantly slowing the RT growth and reducing mix.

  3. TESLA Report 2003-19 THE SHORT-RANGE TRANSVERSE WAKE

    E-Print Network [OSTI]

    TESLA Report 2003-19 THE SHORT-RANGE TRANSVERSE WAKE FUNCTION FOR TESLA ACCELERATING STRUCTURE T of a Free Electron Laser in TESLA project requires very short bunches. It results in a very long interaction calculate the short-range transverse wakefields of the TESLA linac accelerating structure. Wake fields

  4. Computational materials science and engineering (CMSE) is a relatively young field. The first-known case study of materials that used digital computers was made shortly after the Second World

    E-Print Network [OSTI]

    Li, Mo

    ~~ * ~~ Computational materials science and engineering (CMSE) is a relatively young field branches of materials science and engineering. As its impact has grown, it has gained a reputation as being such tedious work as data acquisition and data analysis. Computational materials science and engineering is

  5. Electrodeless short pulse laser

    SciTech Connect (OSTI)

    Proud, J.M.; Baird, D.H.; Kramer, J.M.; Lester, J.E.

    1986-06-03T23:59:59.000Z

    A system is described for the generation of coherent beams of radiation, which consists of: a tube defining a resonant cavity containing a discharge plasma capable of producing coherent radiation, the tube having an elongated shape along an optical axis along the longitudinal axis of the tube, the tube having end portions and an elongated constricted portion connecting the end portions, and the tube having laser windows sealing the end portions to form a closed envelope containing the discharge plasma, a mirror on the optical axis near at least one end of the tube, first and second external electrode means on the outside surfaces of the tube adjacent the opposite ends of the tube, the external electrode means being capacitively coupled to the discharge plasma, and means for providing a source of short pulses electrically to the first external electrode means and means for coupling the second external electrode means to a point of reference potential, further characterized by first and second internal electrode means respectively adjacent the first and second external electrode means and capacitively coupled thereto, the tube having end portions sealed to form a closed envelope containing the discharge plasma and the internal electrode means.

  6. Hydrodynamic transport coefficients in relativistic scalar field theory

    SciTech Connect (OSTI)

    Jeon, S. [Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)] [Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States)

    1995-09-15T23:59:59.000Z

    Hydrodynamic transport coefficients may be evaluated from first principals in a weakly coupled scalar field theory at an arbitrary temperature. In a theory with cubic and quartic interactions, the infinite class of diagrams which contributes to the leading weak coupling behavior is identified and summed. The resulting expression may be reduced to a single linear integral equation, which is shown to be identical to the corresponding result obtained from a linearized Boltzmann equation describing effective thermal excitations with temperature-dependent masses and scattering amplitudes. The effective Boltzmann equation is valid even at very high temperature where the thermal lifetime and mean free path are short compared to the Compton wavelength of the fundamental particles. Numerical results for the shear and the bulk viscosities are presented.

  7. SHACKLING SHORT SELLERS: THE 2008 SHORTING BAN Ekkehart Boehmer

    E-Print Network [OSTI]

    Lin, Xiaodong

    degradation in market quality, as measured by spreads, price impacts, and intraday volatility. Prices,000 financial stocks. In this paper, we study changes in stock prices, the rate of short sales most short sales in nearly 1,000 financial stocks. In this paper, we study changes in stock prices

  8. A New Multi-wavelength Solar Telescope: Optical and Near-infrared Solar Eruption Tracer (ONSET)

    E-Print Network [OSTI]

    Fang, C; Li, Z; Ding, M D; Dai, Y; Zhang, X Y; Mao, W J; Zhang, J P; Li, T; Liang, Y J; Lu, H T

    2013-01-01T23:59:59.000Z

    A new multi-wavelength solar telescope, Optical and Near-infrared Solar Eruption Tracer (ONSET) of Nanjing University, was constructed, being fabricated by Nanjing Institute of Astronomical Optics & Technology and run in cooperation with Yunnan Astronomical Observatory. ONSET is able to observe the Sun in three wavelength windows: He {\\small I} 10830 \\AA, H$\\alpha$, and white-light at 3600 \\AA and 4250 \\AA, which are selected in order to obtain the dynamics in the corona, chromosphere, and the photosphere simultaneously. Full-disk or partial-disk solar images with a field of 10 arcmin at three wavelengths can be obtained nearly simultaneously. It is designed to trace solar eruptions with high spatial and temporal resolutions. This telescope was installed at a new solar observing site near Fuxian Lake in Yunnan Province, southwest China. The site is located at E102N24, with an altitude of 1722 m. The seeing is stable and of high quality. We give a brief description of the scientific objectives and the basi...

  9. Highly efficient entanglement swapping and teleportation at telecom wavelength

    E-Print Network [OSTI]

    Rui-Bo Jin; Masahiro Takeoka; Utako Takagi; Ryosuke Shimizu; Masahide Sasaki

    2014-10-01T23:59:59.000Z

    Entanglement swapping at telecom wavelengths is at the heart of quantum networking in optical fiber infrastructures. Although entanglement swapping has been demonstrated experimentally so far using various types of entangled photon sources both in near-infrared and telecom wavelength regions, the rate of swapping operation has been too low to be applied to practical quantum protocols, due to limited efficiency of entangled photon sources and photon detectors. Here we demonstrate drastic improvement of the efficiency at telecom wavelength by using two ultra-bright entangled photon sources and four highly efficient superconducting nanowire single photon detectors.We have attained a four-fold coincidence count rate of 108 counts per second, which is three orders higher than the previous experiments at telecom wavelengths. A raw (net) visibility in a Hong-Ou-Mandel interference between the two independent entangled sources was 73.3 $\\pm$ 1.0% (85.1 $\\pm$ 0.8%). We performed the teleportation and entanglement swapping, and obtained a fidelity of 76.3% in the swapping test.Our results on the coincidence count rates are comparable with the ones ever recorded in teleportation/swaping and multi-photon entanglement generation experiments at around 800\\,nm wavelengths. Our setup opens the way to practical implementation of device-independent quantum key distribution and its distance extension by the entanglement swapping as well as multi-photon entangled state generation in telecom band infrastructures with both space and fiber links.

  10. LibShortText: A Library for Short-text Classification and Analysis LibShortText: A Library for Short-text Classification and

    E-Print Network [OSTI]

    Lin, Chih-Jen

    LibShortText: A Library for Short-text Classification and Analysis LibShortText: A Library for Short-text Classification and Analysis Hsiang-Fu Yu rofuyu@cs.utexas.edu Department of Computer Science University, Taipei 106, Taiwan Editor: Editor name Abstract LibShortText is an open source library for short

  11. Fabrication and long-wavelength characterization of neat and chemically modified graphene

    SciTech Connect (OSTI)

    Kalugin, Nikolai G. [Departments of Materials Engineering and Chemistry, New Mexico Tech, Socorro, NM 87801 (United States)

    2014-03-31T23:59:59.000Z

    Graphene, a single- or several layer-thick carbon, attracts significant research activity because of its exceptional material properties. Graphene is a promising material for optoelectronic applications. Neat graphene demonstrates potential as a material for long wavelength photodetectors working at elevated temperatures. Chemical modification of graphene opens up many new applications of this material in electronics, in new composite materials, and in new catalysts for different chemical processes. Chemical vapor deposition-grown large-area graphene can be successfully modified with the creation of benzyne attachments. The investigation of microwave properties is an important part of graphene research. Two variants of near-field long wavelength microscopy were found efficient with graphene. Measurements with a probe formed by an electrically open end of a 4 GHz half-lambda parallel-strip transmission line resonator allow the implementation of an electrodynamic model of graphene microwave impedance. The results of near-field scanning superconducting quantum interference device (SQUID) RF microscopy of graphite and graphene at 200 MHz shed light on mechanisms of AC graphene response: screening currents induced in graphene by an external RF magnetic field tend to localize near structural defects.

  12. Broadly defining lasing wavelengths in single bandgap-graded semiconductor nanowires

    E-Print Network [OSTI]

    Yang, Zongyin; Wang, Delong; Meng, Chao; Wu, Zhemin; Wang, Yong; Ma, Yaoguang; Dai, Lun; Liu, Xiaowei; Hasan, Tawfique; Liu, Xu; Yang, Qing

    2014-05-05T23:59:59.000Z

    -wide wavelength tunable light emitting devices, high-performance field-effect transistors and high-efficiency solar cells in identical NWs.27-30 Very recently, multicolor lasing is realized from a single bandgap-graded CdSSe nanoribbon, by multi... from the left narrow-bandgap end of the NW is centered at 638 nm with a full width at half-maximum (FWHM) of 30 nm (Figure 2e, bottom). With increasing pump density, bright red spots emerged at both ends of the NW (Figure 2d), and the measured...

  13. Ultra-sensitive surface absorption spectroscopy using sub-wavelength diameter optical fibers

    E-Print Network [OSTI]

    F. Warken; E. Vetsch; D. Meschede; M. Sokolowski; A. Rauschenbeutel

    2007-06-22T23:59:59.000Z

    The guided modes of sub-wavelength diameter air-clad optical fibers exhibit a pronounced evanescent field. The absorption of particles on the fiber surface is therefore readily detected via the fiber transmission. We show that the resulting absorption for a given surface coverage can be orders of magnitude higher than for conventional surface spectroscopy. As a demonstration, we present measurements on sub-monolayers of 3,4,9,10-perylene-tetracarboxylic dianhydride (PTCDA) molecules at ambient conditions, revealing the agglomeration dynamics on a second to minutes timescale.

  14. Residual zonal flows in tokamaks and stellarators at arbitrary wavelengths

    E-Print Network [OSTI]

    Monreal, P; Sánchez, E; Parra, F I; Bustos, A; Könies, A; Kleiber, R; Görler, T

    2015-01-01T23:59:59.000Z

    In the linear collisionless limit, a zonal potential perturbation in a toroidal plasma relaxes, in general, to a non-zero residual value. Expressions for the residual value in tokamak and stellarator geometries, and for arbitrary wavelengths, are derived. These expressions involve averages over the lowest order particle trajectories, that typically cannot be evaluated analytically. In this work, an efficient numerical method for the evaluation of such expressions is reported. It is shown that this method is faster than direct gyrokinetic simulations. Calculations of the residual value in stellarators are provided for much shorter wavelengths than previously available in the literature. Electrons must be treated kinetically in stellarators because, unlike in tokamaks, kinetic electrons modify the residual value even at long wavelengths. This effect, that had already been predicted theoretically, is confirmed by gyrokinetic simulations.

  15. Optimised low-loss multilayers for imaging with sub-wavelength resolution in the visible wavelength range

    E-Print Network [OSTI]

    Pastuszczak, Anna

    2011-01-01T23:59:59.000Z

    We optimise the effective skin-depth and resolution of Ag-TiO2, Ag-SrTiO3, and Ag-GaP multilayers for imaging with sub-wavelength resolution. In terms of transmission and resolution the optimised multilayers outperform simple designs based on combined use of effective medium theory, impedance matching and Fabry-Perot resonances. For instance, an optimised Ag-GaP multilayer consisting of only 17 layers, operating at the wavelength of 490 nm and having a total thickness equal to one wavelength, combines 78% intensity transmission with a resolution of 60 nm. It is also shown that use of the effective medium theory leads to sub-optimal multilayer designs with respect to the trade-off between the skin depth and resolution already when the period of the structure is on the order of 40 nm or larger.

  16. Effects of free-electron-laser field fluctuations on the frequency response of driven atomic resonances

    E-Print Network [OSTI]

    G. M. Nikolopoulos; P. Lambropoulos

    2012-09-11T23:59:59.000Z

    We study the effects of field fluctuations on the total yields of Auger electrons, obtained in the excitation of neutral atoms to a core-excited state by means of short-wavelength free-electron-laser pulses. Beginning with a self-contained analysis of the statistical properties of fluctuating free-electron-laser pulses, we analyse separately and in detail the cases of single and double Auger resonances, focusing on fundamental phenomena such as power broadening and ac Stark (Autler-Townes) splitting. In certain cases, field fluctuations are shown to influence dramatically the frequency response of the resonances, whereas in other cases the signal obtained may convey information about the bandwidth of the radiation as well as the dipole moment between Auger states.

  17. JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 18, NO. 12, DECEMBER 2000 2167 10 Gb/s Multiple Wavelength, Coherent Short Pulse

    E-Print Network [OSTI]

    Jalali. Bahram

    /s by year 2002 with a further doubling every two years. Utilizing the entire 40 THz low loss transmission links. The preferred approach to utilize the low loss transmis- sion window of silica fibers calculate the coherence degradation due to amplification of incoherent energy during the SC generation

  18. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, Jerry M. (Lakewood, CO); Kurtz, Sarah R. (Golden, CO)

    1992-01-01T23:59:59.000Z

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect.

  19. Tunnel junction multiple wavelength light-emitting diodes

    DOE Patents [OSTI]

    Olson, J.M.; Kurtz, S.R.

    1992-11-24T23:59:59.000Z

    A multiple wavelength LED having a monolithic cascade cell structure comprising at least two p-n junctions, wherein each of said at least two p-n junctions have substantially different band gaps, and electrical connector means by which said at least two p-n junctions may be collectively energized; and wherein said diode comprises a tunnel junction or interconnect. 5 figs.

  20. Laser cooling and trapping of potassium at magic wavelengths

    E-Print Network [OSTI]

    M. S. Safronova; U. I. Safronova; Charles W. Clark

    2013-01-14T23:59:59.000Z

    We carry out a systematic study of the static and dynamic polarizabilities of the potassium atom using a first-principles high-precision relativistic all-order method in which all single, double, and partial triple excitations of the Dirac-Fock wave functions are included to all orders of perturbation theory. Recommended values are provided for a large number of electric-dipole matrix elements. Static polarizabilities of the 4s, 4p_j, 5s, 5p_j, and 3d_j states are compared with other theory and experiment where available. We use the results of the polarizability calculations to identify magic wavelengths for the 4s-np transitions for $n = 4, 5$, i.e. those wavelengths for which the two levels have the same ac Stark shifts. These facilitate state-insensitive optical cooling and trapping. The magic wavelengths for the $4s-5p$ transitions are of particular interest for attaining a quantum gas of potassium at high phase-space density. We find 20 such wavelengths in the technically interest region of 1050-1130 nm. Uncertainties of all recommended values are estimated.

  1. Resonator design for a visible wavelength free-electron laser (*)

    SciTech Connect (OSTI)

    Bhowmik, A.; Lordi, N. (Rockwell International Corp., Canoga Park, CA (United States). Rocketdyne Div.); Ben-Zvi, I.; Gallardo, J. (Brookhaven National Lab., Upton, NY (United States))

    1990-01-01T23:59:59.000Z

    Design requirements for a visible wavelength free-electron laser being developed at the Accelerator Test Facility at Brookhaven National Laboratory are presented along with predictions of laser performance from 3-D numerical simulations. The design and construction of the optical resonator, its alignment and control systems are also described. 15 refs., 8 figs., 4 tabs.

  2. Stellar Surface Convection, Line Asymmetries, and Wavelength Shifts

    E-Print Network [OSTI]

    , Box 43, SE­22100 Lund, Sweden Abstract. Wavelength positions of photospheric absorption lines may the sinking and cooler (darker) gas. For the Sun, the effect is around 300 m s \\Gamma1 , expected to increase), and intergranular lanes with local redshifts (sinking motion), as naturally expected in convective energy transfer

  3. Magic Wavelength for Hydrogen 1S-2S Transition

    E-Print Network [OSTI]

    Kawasaki, Akio

    2015-01-01T23:59:59.000Z

    The magic wavelength for an optical lattice for hydrogen atoms that cancels the first order AC Stark shift of 1S-2S transition is calculated to be 513 nm. The amount of AC Stark shift $ \\Delta E = -1.19$ kHz/(10kW/cm$^2$) and the slope $d\\Delta E/d \

  4. Optical add/drop filter for wavelength division multiplexed systems

    DOE Patents [OSTI]

    Deri, Robert J. (Pleasanton, CA); Strand, Oliver T. (Castro Valley, CA); Garrett, Henry E. (Livermore, CA)

    2002-01-01T23:59:59.000Z

    An optical add/drop filter for wavelength division multiplexed systems and construction methods are disclosed. The add/drop filter includes a first ferrule having a first pre-formed opening for receiving a first optical fiber; an interference filter oriented to pass a first set of wavelengths along the first optical fiber and reflect a second set of wavelengths; and, a second ferrule having a second pre-formed opening for receiving the second optical fiber, and the reflected second set of wavelengths. A method for constructing the optical add/drop filter consists of the steps of forming a first set of openings in a first ferrule; inserting a first set of optical fibers into the first set of openings; forming a first set of guide pin openings in the first ferrule; dividing the first ferrule into a first ferrule portion and a second ferrule portion; forming an interference filter on the first ferrule portion; inserting guide pins through the first set of guide pin openings in the first ferrule portion and second ferrule portion to passively align the first set of optical fibers; removing material such that light reflected from the interference filter from the first set of optical fibers is accessible; forming a second set of openings in a second ferrule; inserting a second set of optical fibers into the second set of openings; and positioning the second ferrule with respect to the first ferrule such that the second set of optical fibers receive the light reflected from the interference filter.

  5. CORONAL MAGNETIC FIELD MEASUREMENTS THROUGH GYRORESONANCE EMISSION

    E-Print Network [OSTI]

    White, Stephen

    Chapter 5 CORONAL MAGNETIC FIELD MEASUREMENTS THROUGH GYRORESONANCE EMISSION Stephen M. White This article reviews the use of gyroresonance emission at radio wavelengths to measure coronal magnetic fields. Keywords: Sun, solar corona, solar magnetic fields, solar radio emission Introduction Since the realization

  6. Short-Term Energy Outlook

    U.S. Energy Information Administration (EIA) Indexed Site

    Chart Gallery for April 2015 Short-Term Energy Outlook U.S. Energy Information Administration Independent Statistics & Analysis 0 20 40 60 80 100 120 140 160 180 200 220 Jan 2014...

  7. Author's personal copy Short communication

    E-Print Network [OSTI]

    s gives J, the air-earth current density J in the global electric circuit, J ¼ sP (1) which is sustainedAuthor's personal copy Short communication Smoke emissions from industrial western Scotland in 1859

  8. Short-Term Energy Outlook

    Gasoline and Diesel Fuel Update (EIA)

    day Forecast -1.0 2012 2013 2014 OPEC countries North America Russia and Caspian Sea Latin America North Sea Other Non-OPEC Source: Short-Term Energy Outlook, November 2013 -1 0...

  9. Enrichment short courses and special

    E-Print Network [OSTI]

    Enrichment short courses and special events specially developed for folks 50 and better. Look better way to spend your summer than expanding your knowledge and enriching your life with an Osher

  10. Surfaces in the interaction of intense long wavelength laser light with plasmas

    SciTech Connect (OSTI)

    Jones, R.D.

    1985-01-01T23:59:59.000Z

    The role of surface in the interaction of intense CO/sub 2/ laser light with plasmas is reviewed. The collisionless absorption of long wavelength light is discussed. Specific comments on the role of ponderomotive forces and profile steepening on resonant absorption are made. It is shown that at intensities above 10/sup 15/W/cm/sup 2/ the absorption is determined by ion acoustic-like surface modes. It is demonstrated experimentally that harmonics up to the forty-sixth can be generated in steep density profiles. Computer simulations and theoretical mechanisms for this phenomena are presented. The self generation of magnetic fields on surfaces is discussed. The role these fields play in the lateral transport of energy, the insulation of the target from hot electrons, and the acceleration of fast ions is discussed.

  11. Visible light stimulating dual-wavelength emission and O vacancy involved energy transfer behavior in luminescence for coaxial nanocable arrays

    SciTech Connect (OSTI)

    Yang, Lei, E-mail: nanoyang@qq.com [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Hunan Province Key Laboratory for Spray Deposition Technology and Application, Hunan University, Changsha 410082 (China); Dong, Jiazhang; Jiang, Zhongcheng [College of Materials Science and Engineering, Hunan University, Changsha 410082 (China); Pan, Anlian; Zhuang, Xiujuan [Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China)

    2014-06-14T23:59:59.000Z

    We report a strategy to investigate O vacancy (V{sub O}) involved energy transfer and dual-wavelength yellow emission in coaxial nanocable. By electric field deposition and subsequent sol-gel template approach, ZnO:Tb/Y{sub 2}O{sub 3}:Eu coaxial nanocable arrays are synthesized. After visible light excitation, system is promoted to O vacancy charge transfer state of V{sub O}(0/+). In the following cross relaxation, energy transfer from V{sub O} to the excitation energy level of Tb{sup 3+} in ZnO:Tb core area. While in Y{sub 2}O{sub 3}:Eu shell area, energy transfer to the excitation energy level of Eu{sup 3+}. Subsequently, dual-wavelength emission is observed. By constructing nanocable with dual-wavelength emission, yellow luminescence is obtained. Adjust doping concentration of Eu{sup 3+} or Tb{sup 3+} in the range of 0.01–0.05, chromaticity coordinates of ZnO:Tb/Y{sub 2}O{sub 3}:Eu nanocable stably stays at yellow region in color space except ZnO:Tb{sub 0.01}/Y{sub 2}O{sub 3}:Eu{sub 0.01}. As Vo states act as media in energy transfer process in nanocablers, visible light can stimulate dual-wavelength emissions. Yellow luminescent nanocable arrays will have great applications in light-emitting diode luminescence.

  12. Three dimensional imaging detector employing wavelength-shifting optical fibers

    DOE Patents [OSTI]

    Worstell, William A. (Framingham, MA)

    1997-01-01T23:59:59.000Z

    A novel detector element structure and method for its use is provided. In a preferred embodiment, one or more inorganic scintillating crystals are coupled through wavelength shifting optical fibers (WLSFs) to position sensitive photomultipliers (PS-PMTs). The superior detector configuration in accordance with this invention is designed for an array of applications in high spatial resolution gamma ray sensing with particular application to SPECT, PET and PVI imaging systems. The design provides better position resolution than prior art devices at a lower total cost. By employing wavelength shifting fibers (WLSFs), the sensor configuration of this invention can operate with a significant reduction in the number of photomultipliers and electronics channels, while potentially improving the resolution of the system by allowing three dimensional reconstruction of energy deposition positions.

  13. Three dimensional imaging detector employing wavelength-shifting optical fibers

    DOE Patents [OSTI]

    Worstell, W.A.

    1997-02-04T23:59:59.000Z

    A novel detector element structure and method for its use is provided. In a preferred embodiment, one or more inorganic scintillating crystals are coupled through wavelength shifting optical fibers (WLSFs) to position sensitive photomultipliers (PS-PMTs). The superior detector configuration in accordance with this invention is designed for an array of applications in high spatial resolution gamma ray sensing with particular application to SPECT, PET and PVI imaging systems. The design provides better position resolution than prior art devices at a lower total cost. By employing wavelength shifting fibers (WLSFs), the sensor configuration of this invention can operate with a significant reduction in the number of photomultipliers and electronics channels, while potentially improving the resolution of the system by allowing three dimensional reconstruction of energy deposition positions. 11 figs.

  14. Apparatus for generating coherent infrared energy of selected wavelength

    DOE Patents [OSTI]

    Stevens, Charles G. (Danville, CA)

    1985-01-01T23:59:59.000Z

    A tunable source (11) of coherent infrared energy includes a heat pipe (12) having an intermediate region (24) at which cesium (22) is heated to vaporizing temperature and end regions (27, 28) at which the vapor is condensed and returned to the intermediate region (24) for reheating and recirculation. Optical pumping light (43) is directed along the axis of the heat pipe (12) through a first end window (17) to stimulate emission of coherent infrared energy which is transmitted out through an opposite end window (18). A porous walled tubulation (44) extends along the axis of the heat pipe (12) and defines a region (46) in which cesium vapor is further heated to a temperature sufficient to dissociate cesium dimers which would decrease efficiency by absorbing pump light (43). Efficient generation of any desired infrared wavelength is realized by varying the wavelength of the pump light (43).

  15. Wavelength-resonant surface-emitting semiconductor laser

    DOE Patents [OSTI]

    Brueck, Steven R. J. (Albuquerque, NM); Schaus, Christian F. (Albuquerque, NM); Osinski, Marek A. (Albuquerque, NM); McInerney, John G. (Cedar Crest, NM); Raja, M. Yasin A. (Albuquerque, NM); Brennan, Thomas M. (Albuquerque, NM); Hammons, Burrell E. (Tijeras, NM)

    1989-01-01T23:59:59.000Z

    A wavelength resonant semiconductor gain medium is disclosed. The essential feature of this medium is a multiplicity of quantum-well gain regions separated by semiconductor spacer regions of higher bandgap. Each period of this medium consisting of one quantum-well region and the adjacent spacer region is chosen such that the total width is equal to an integral multiple of 1/2 the wavelength in the medium of the radiation with which the medium is interacting. Optical, electron-beam and electrical injection pumping of the medium is disclosed. This medium may be used as a laser medium for single devices or arrays either with or without reflectors, which may be either semiconductor or external.

  16. Time-Multiplexed Measurements of Nonclassical Light at Telecom Wavelengths

    E-Print Network [OSTI]

    G. Harder; C. Silberhorn; J. Rehacek; Z. Hradil; L. Motka; B. Stoklasa; L. L. Sanchez-Soto

    2014-06-13T23:59:59.000Z

    We report the experimental reconstruction of the statistical properties of an ultrafast pulsed type-II parametric down conversion source in a periodically poled KTP waveguide at telecom wavelengths, with almost perfect photon-number correlations. We used a photon-number-resolving time-multiplexed detector based on a fiber-optical setup and a pair of avalanche photodiodes. By resorting to a germane data-pattern tomography, we assess the properties of the nonclassical light states states with unprecedented precision.

  17. Nanoantenna enhancement for telecom-wavelength superconducting single photon detectors

    E-Print Network [OSTI]

    Heath, Robert M; Drysdale, Timothy D; Miki, Shigehito; Giannini, Vincenzo; Maier, Stefan A; Hadfield, Robert H

    2015-01-01T23:59:59.000Z

    Superconducting nanowire single photon detectors are rapidly emerging as a key infrared photon-counting technology. Two front-side-coupled silver dipole nanoantennas, simulated to have resonances at 1480 nm and 1525 nm, were fabricated in a two-step process. An enhancement of 50% to 130% in the system detection efficiency was observed when illuminating the antennas. This offers a pathway to increasing absorption into superconducting nanowires, creating larger active areas, and achieving more efficient detection at longer wavelengths.

  18. Upconverting device for enhanced recogntion of certain wavelengths of light

    DOE Patents [OSTI]

    Kross, Brian; McKIsson, John (Jack) E; McKisson, John; Weisenberger, Andrew; Xi, Wenze; Zorn, Carl

    2013-05-21T23:59:59.000Z

    An upconverting device for enhanced recognition of selected wavelengths is provided. The device comprises a transparent light transmitter in combination with a plurality of upconverting nanoparticles. The device may a lens in eyewear or alternatively a transparent panel such as a window in an instrument or machine. In use the upconverting device is positioned between a light source and the eye(s) of the user of the upconverting device.

  19. Enhanced subthreshold electron-positron production in short laser pulses

    E-Print Network [OSTI]

    A. I. Titov; H. Takabe; B. Kampfer; A. Hosaka

    2012-05-17T23:59:59.000Z

    The emission of electron-positron pairs off a probe photon propagating through a polarized short-pulsed electromagnetic (e.g.\\ laser) wave field is analyzed. A significant increase of the total cross section of pair production in the subthreshold region is found for decreasing laser pulse duration even in case of moderate laser pulse intensities.

  20. Particle Acceleration by a Short-Intense Elliptically Polarized Electromagnetic

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Particle Acceleration by a Short-Intense Elliptically Polarized Electromagnetic Pulse Propagating to plasma physics and particle accelerators. The interaction physics of fields with particles has also been, Colchester CO4 3SQ, U.K. Abstract. The motion of a charged particle driven by an electromagnetic pulse

  1. Ultrafast laser induced periodic sub-wavelength aluminum surface structures and nanoparticles in air and liquids

    SciTech Connect (OSTI)

    Kuladeep, Rajamudili; Dar, Mudasir H.; Rao, D. Narayana, E-mail: dnrsp@uohyd.ac.in, E-mail: dnr-laserlab@yahoo.com [School of Physics, University of Hyderabad, Hyderabad 500046 (India); Deepak, K. L. N. [Department of Physics and Center for Research in Photonics, University of Ottawa, 150 Louis Pasteur, Ottawa K1N6N5, Ontario (Canada)

    2014-09-21T23:59:59.000Z

    In this communication, we demonstrate the generation of laser-induced periodic sub-wavelength surface structures (LIPSS) or ripples on a bulk aluminum (Al) and Al nanoparticles (NPs) by femtosecond (fs) laser direct writing technique. Laser irradiation was performed on Al surface at normal incidence in air and by immersing in ethanol (C{sub 2}H{sub 5}OH) and water (H{sub 2}O) using linearly polarized Ti:sapphire fs laser pulses of ?110 fs pulse duration and ?800?nm wavelength. Field emission scanning electron microscope is utilized for imaging surface morphology of laser written structures and it reveals that the spatial periodicity as well as the surface morphology of the LIPSS depends on the surrounding dielectric medium and also on the various laser irradiation parameters. The observed LIPSS have been classified as low spatial frequency LIPSS which are perpendicularly oriented to the laser polarization with a periodicity from 460 to 620?nm and high spatial frequency LIPSS which spectacles a periodicity less than 100?nm with the orientation parallel to the polarization of the incident laser beam. Fabricated colloidal solutions, which contain the Al NPs, were characterized by UV-Vis absorption spectroscopy and transmission electron microscopy (TEM). TEM results reveal the formation of internal cavities in Al NPs both in ethanol and water. Formation mechanism of LIPSS and cavities inside the nanoparticles are discussed in detail.

  2. BLAST05: POWER SPECTRA OF BRIGHT GALACTIC CIRRUS AT SUBMILLIMETER WAVELENGTHS

    SciTech Connect (OSTI)

    Roy, Arabindo; Martin, Peter G.; Netterfield, Calvin B. [Department of Astronomy and Astrophysics, University of Toronto, 50 St. George Street, Toronto, ON M5S 3H4 (Canada); Ade, Peter A. R.; Griffin, Matthew; Hargrave, Peter C.; Mauskopf, Philip [Department of Physics and Astronomy, Cardiff University, 5 The Parade, Cardiff, CF24 3AA (United Kingdom); Bock, James J. [Jet Propulsion Laboratory, Pasadena, CA 91109-8099 (United States); Chapin, Edward L.; Halpern, Mark; Marsden, Gaelen [Department of Physics and Astronomy, University of British Columbia, 6224 Agricultural Road, Vancouver, BC V6T 1Z1 (Canada); Devlin, Mark J.; Dicker, Simon R.; Klein, Jeff; Rex, Marie [Department of Physics and Astronomy, University of Pennsylvania, 209 South 33rd Street, Philadelphia, PA 19104 (United States); Gundersen, Joshua O. [Department of Physics, University of Miami, 1320 Campo Sano Drive, Carol Gables, FL 33146 (United States); Hughes, David H. [Instituto Nacional de AstrofIsica Optica y Electronica (INAOE), Aptdo. Postal 51 y 72000 Puebla (Mexico); Miville-Deschenes, Marc-Antoine [Institut d' Astrophysique Spatiale, UMR8617, Universite Paris-Sud, F-91405, Orsay (France); Olmi, Luca [Physics Department, University of Puerto Rico, Rio Piedras Campus, P.O. Box 23343, UPR station, San Juan (Puerto Rico); Patanchon, Guillaume, E-mail: aroy@cita.utoronto.c [Laboratoire APC, 10, rue Alice Domon et Leonie Duquet 75205 Paris (France)

    2010-01-10T23:59:59.000Z

    We report multi-wavelength power spectra of diffuse Galactic dust emission from Balloon-borne Large Aperture Submillimeter Telescope observations at 250, 350, and 500 mum in Galactic plane fields in Cygnus X and Aquila. These submillimeter power spectra statistically quantify the self-similar structure observable over a broad range of scales and can be used to assess the cirrus noise which limits the detection of faint point sources. The advent of submillimeter surveys with the Herschel Space Observatory makes the wavelength dependence a matter of interest. We show that the observed relative amplitudes of the power spectra can be related through a spectral energy distribution (SED). Fitting a simple modified black body to this SED, we find the dust temperature in Cygnus X to be 19.8 +- 1.5 K and in the Aquila region 16.8 +- 0.8 K. Our empirical estimates provide important new insight into the substantial cirrus noise that will be encountered in forthcoming observations.

  3. Effects of laser energy and wavelength on the analysis of LiFePO? using laser assisted atom probe tomography

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

    Santhanagopalan, Dhamodaran [Univ. of California, San Diego, CA (United States); Khalifah, Peter [Stony Brook Univ., NY (United States); Brookhaven National Lab., Upton, NY (United States); Schreiber, Daniel K. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Perea, Daniel E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Martens, Richard L. [Univ. of Alabama, Tuscaloosa, AL (United States); Janssen, Yuri [Stony Brook Univ., NY (United States); Meng, Ying Shirley [Univ. of California, San Diego, CA (United States)

    2015-01-01T23:59:59.000Z

    The effects of laser wavelength (355 nm and 532 nm) and laser pulse energy on the quantitative analysis of LiFePO? by atom probe tomography are considered. A systematic investigation of ultraviolet (UV, 355 nm) and green (532 nm) laser assisted field evaporation has revealed distinctly different behaviors. With the use of a UV laser, the major issue was identified as the preferential loss of oxygen (up to 10 at%) while other elements (Li, Fe and P) were observed to be close to nominal ratios. Lowering the laser energy per pulse to 1 pJ/pulse from 50 pJ/pulse increased the observed oxygen concentration to nearer its correct stoichiometry, which was also well correlated with systematically higher concentrations of ¹?O?? ions. Green laser assisted field evaporation led to the selective loss of Li (33% deficiency) and a relatively minor O deficiency. The loss of Li is likely a result of selective dc evaporation of Li between or after laser pulses. Comparison of the UV and green laser data suggests that the green wavelength energy was absorbed less efficiently than the UV wavelength because of differences in absorption at 355 and 532 nm for LiFePO?. Plotting of multihit events on Saxey plots also revealed a strong neutral O? loss from molecular dissociation, but quantification of this loss was insufficient to account for the observed oxygen deficiency.

  4. Effects of laser energy and wavelength on the analysis of LiFePO? using laser assisted atom probe tomography

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

    Santhanagopalan, Dhamodaran; Khalifah, Peter; Schreiber, Daniel K.; Perea, Daniel E.; Martens, Richard L.; Janssen, Yuri; Meng, Ying Shirley

    2015-01-01T23:59:59.000Z

    The effects of laser wavelength (355 nm and 532 nm) and laser pulse energy on the quantitative analysis of LiFePO? by atom probe tomography are considered. A systematic investigation of ultraviolet (UV, 355 nm) and green (532 nm) laser assisted field evaporation has revealed distinctly different behaviors. With the use of a UV laser, the major issue was identified as the preferential loss of oxygen (up to 10 at%) while other elements (Li, Fe and P) were observed to be close to nominal ratios. Lowering the laser energy per pulse to 1 pJ/pulse from 50 pJ/pulse increased the observed oxygenmore »concentration to nearer its correct stoichiometry, which was also well correlated with systematically higher concentrations of ¹?O?? ions. Green laser assisted field evaporation led to the selective loss of Li (33% deficiency) and a relatively minor O deficiency. The loss of Li is likely a result of selective dc evaporation of Li between or after laser pulses. Comparison of the UV and green laser data suggests that the green wavelength energy was absorbed less efficiently than the UV wavelength because of differences in absorption at 355 and 532 nm for LiFePO?. Plotting of multihit events on Saxey plots also revealed a strong neutral O? loss from molecular dissociation, but quantification of this loss was insufficient to account for the observed oxygen deficiency.« less

  5. SHORT REVIEW Butterfly genomics eclosing

    E-Print Network [OSTI]

    Beldade, Patrícia

    SHORT REVIEW Butterfly genomics eclosing P Beldade1 , WO McMillan2 and A Papanicolaou3 1 Section to an explosion of genomic data and the emergence of new research avenues. Evolutionary and ecological functional genomics, with its focus on the genes that affect ecological success and adaptation in natural populations

  6. University Policy Process Short Version

    E-Print Network [OSTI]

    Mohanty, Saraju P.

    Rev. 5/09 University Policy Process Short Version Conduct Analysis Draft Documents Get Approvals. Identify policy owner 3. Assemble team 4. Engage Stakeholders 5. Draft policy 6. Submit proposed policy approves (or not) Do we need a policy? 11. Plan communication & training 12. UPO posts approved policy

  7. Effects of Laser Energy and Wavelength on the Analysis of LiFePO4...

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

    Laser Energy and Wavelength on the Analysis of LiFePO4 Using Laser Assisted Atom Probe Tomography. Effects of Laser Energy and Wavelength on the Analysis of LiFePO4 Using Laser...

  8. Setting in the Modern Short Story

    E-Print Network [OSTI]

    Hodgson, Elizabeth

    1913-06-05T23:59:59.000Z

    . Thompson , D~'I G. The Ph1losophY ot Fiation. Lo on" l8~. Wh1tcomb , S. L. st of th Novei . Boston, 1 ·5. II. II. L short-starl: AI 'bright, ].'velyn 1La.Y . Tltle Short story. N. Y., 1 O? Barrett , Chas. P. Short story Writing . N. ., 188. Canby... . III. Matthews, Brander . The Short - st ory. N. :x.., 1 07 . Patton, Wm. International Short-stori e , 2 vols • • Y., 1 ~lO. Short-stor y Classios--Amerlcan , 5 vols ., N. Y. t 1':;)05 . , , Short-story Clas8~cs--Foreign , 5 vole . N. ¥ . ! II...

  9. SHORT COMMUNICATION Fatigue Assessment in the Field: Validation of a

    E-Print Network [OSTI]

    Psychomotor Vigilance Task Nicole Lamond, Drew Dawson, and Gregory D. Roach LAMOND N, DAWSON D, ROACH GD

  10. Single-fiber-laser-based wavelength tunable excitation for coherent Raman spectroscopy

    E-Print Network [OSTI]

    Su, Jue; Xie, Ruxin; Johnson, Carey K.; Hui, Rongqing

    2013-06-01T23:59:59.000Z

    in this co- herent detection process is I#1;t#2; #3; ? ? j ~Es#1;t#2; #4; ~ESRS#1;t#2;j2; (8) where ? ? is the photodetector responsivity at the Stokes wavelength and ~ESRS#1;t#2; #3; IFT#5; ~ESRS#1;?#2;#7; is the time domain re- sponse of SRS induced... the response, ~Rsp#1;?#2; #3; FT#5; ~Ep#1;t#2; · ~E#6;s #1;t#2;#7; · L#1;?#2;; (2) where ~Ep#1;t#2; and ~Es#1;t#2; are the time-domain electric fields of the chirped pump and Stokes pulses, and L#1;?#2; #3; X m Bm ?m ? ? ? j?m?2 (3) with Bm a proportionality...

  11. Spatiotemporal focusing dynamics in plasmas at X-ray wavelength

    SciTech Connect (OSTI)

    Sharma, A., E-mail: a-physics2001@yahoo.com; Tibai, Z. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary)] [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Hebling, J. [Institute of Physics, University of Pecs, Pecs–7624 (Hungary) [Institute of Physics, University of Pecs, Pecs–7624 (Hungary); Szentagothai Research Centre, University of Pecs, Pecs-7624 (Hungary); Mishra, S. K. [Institute for Plasma Research, Gandhinagar (India)] [Institute for Plasma Research, Gandhinagar (India)

    2014-03-15T23:59:59.000Z

    Using a finite curvature beam, we investigate here the spatiotemporal focusing dynamics of a laser pulse in plasmas at X-ray wavelength. We trace the dependence of curvature parameter on the focusing of laser pulse and recognize that the self-focusing in plasma is more intense for the X-ray laser pulse with curved wavefront than with flat wavefront. The simulation results demonstrate that spatiotemporal focusing dynamics in plasmas can be controlled with the appropriate choice of beam-plasma parameters to explore the high intensity effects in X-ray regime.

  12. Dual wavelength laser damage testing for high energy lasers.

    SciTech Connect (OSTI)

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

    2010-05-01T23:59:59.000Z

    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.

  13. Multiplexed absorption tomography with calibration-free wavelength modulation spectroscopy

    SciTech Connect (OSTI)

    Cai, Weiwei; Kaminski, Clemens F., E-mail: cfk23@cam.ac.uk [Department of Chemical Engineering and Biotechnology, University of Cambridge, Cambridge CB2 3RA (United Kingdom)

    2014-04-14T23:59:59.000Z

    We propose a multiplexed absorption tomography technique, which uses calibration-free wavelength modulation spectroscopy with tunable semiconductor lasers for the simultaneous imaging of temperature and species concentration in harsh combustion environments. Compared with the commonly used direct absorption spectroscopy (DAS) counterpart, the present variant enjoys better signal-to-noise ratios and requires no baseline fitting, a particularly desirable feature for high-pressure applications, where adjacent absorption features overlap and interfere severely. We present proof-of-concept numerical demonstrations of the technique using realistic phantom models of harsh combustion environments and prove that the proposed techniques outperform currently available tomography techniques based on DAS.

  14. Dependence of Turing pattern wavelength on diffusion rate

    SciTech Connect (OSTI)

    Ouyang, Q. (Center for Nonlinear Dynamics and Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States)); Li, R.; Li, G. (Department of Chemistry, The Tsinghua University, Beijing 10008 (China)); Swinney, H.L. (Center for Nonlinear Dynamics and Department of Physics, The University of Texas at Austin, Austin, Texas 78712 (United States))

    1995-02-08T23:59:59.000Z

    The relation between the diffusion coefficient of reactants and the wavelength of Turing patterns is examined in experiments on the chlorite--iodide--malonic acid (CIMA) reaction in gel media. The diffusion coefficients in polyacrylamide and agarose gels are varied by varying the gel densities. The diffusion coefficient [ital D] of NaCl is found to vary from 0.5[times]10[sup [minus]5] to 1.8[times]10[sup [minus]5] cm[sup 2]/s for the gel conditions considered. The CIMA reactants are assumed to have diffusion coefficients that are directly proportional to that of NaCl. The wavelength [lambda] of the observed hexagonal patterns (0.13--0.28 mm) varies in accord with the predicted relation for Turing patterns, [lambda][similar to][ital D][sup 1/2]. Moreover, the predicted relationship to a characteristic period of oscillation [tau], [lambda]=(2[pi][tau][ital D])[sup 1/2], is supported by measurements of [tau] just beyond a Hopf bifurcation in a stirred flow reactor.

  15. Overcoming the far-field diffraction limit via absorbance modulation

    E-Print Network [OSTI]

    Tsai, Hsin-Yu Sidney

    2011-01-01T23:59:59.000Z

    Diffraction limits the resolution of far-field lithography and imaging to about half of the wavelength, which greatly limits the capability of optical techniques. The proposed technique with absorbance modulation aims to ...

  16. Hard probes of short-range nucleon-nucleon correlations

    E-Print Network [OSTI]

    J. Arrington; D. W. Higinbotham; G. Rosner; M. Sargsian

    2012-03-26T23:59:59.000Z

    One of the primary goals of nuclear physics is providing a complete description of the structure of atomic nuclei. While mean-field calculations provide detailed information on the nuclear shell structure for a wide range of nuclei, they do not capture the complete structure of nuclei, in particular the impact of small, dense structures in nuclei. The strong, short-range component of the nucleon-nucleon potential yields hard interactions between nucleons which are close together, generating a high-momentum tail to the nucleon momentum distribution, with momenta well in excess of the Fermi momentum. This high-momentum component of the nuclear wave-function is one of the most poorly understood parts of nuclear structure. Utilizing high-energy probes, we can isolate scattering from high-momentum nucleons, and use these measurements to examine the structure and impact of short-range nucleon-nucleon correlations. Over the last decade we have moved from looking for evidence of such short-range structures to mapping out their strength in nuclei and examining their isospin structure. This has been made possible by high-luminosity and high-energy accelerators, coupled with an improved understanding of the reaction mechanism issues involved in studying these structures. We review the general issues related to short-range correlations, survey recent experiments aimed at probing these short-range structures, and lay out future possibilities to further these studies.

  17. Compton Process in Intense Short Laser Pulses

    E-Print Network [OSTI]

    K. Krajewska; J. Z. Kaminski

    2012-06-05T23:59:59.000Z

    The spectra of Compton radiation emitted during electron scattering off an intense laser beam are calculated using the framework of strong-field quantum electrodynamics. We model these intense laser beams as finite length plane-wave-fronted pulses, similar to Neville and Rohrlich [Phys. Rev. D {\\bf 3}, 1692 (1971)], or as trains of such pulses. Expressions for energy and angular distributions of Compton photons are derived such that a comparison of both situations becomes meaningful. Comparing frequency distributions for both an isolated laser pulse and a laser pulse train, we find a very good agreement between the results for long pulse durations which breaks down however for ultrashort laser pulses. The dependence of angular distributions of emitted radiation on a pulse duration is also investigated. Pronounced asymmetries of angular distributions are found for very short laser pulses, which gradually disappear with increasing the number of laser field oscillations. Those asymmetries are attributed to asymmetries of the vector potential describing an incident laser beam.

  18. Breit-Wheeler process in very short electromagnetic pulses

    E-Print Network [OSTI]

    A. I. Titov; B. Kampfer; H. Takabe; A. Hosaka

    2013-03-26T23:59:59.000Z

    The generalized Breit-Wheeler process, i.e. the emission of $e^+e^-$ pairs off a probe photon propagating through a polarized short-pulsed electromagnetic (e.g.\\ laser) wave field, is analyzed. We show that the production probability is determined by the interplay of two dynamical effects. The first one is related to the shape and duration of the pulse and the second one is the non-linear dynamics of the interaction of $e^\\pm$ with the strong electromagnetic field. The first effect manifests itself most clearly in the weak-field regime, where the small field intensity is compensated by the rapid variation of the electromagnetic field in a limited space-time region, which intensifies the few-photon events and can enhance the production probability by orders of magnitude compared to an infinitely long pulse. Therefore, short pulses may be considered as a powerful amplifier. The non-linear dynamics in the multi-photon Breit-Wheeler regime plays a decisive role at large field intensities, where effects of the pulse shape and duration are less important. In the transition regime, both effects must be taken into account simultaneously. We provide suitable expressions for the $e^+e^-$ production probability for kinematic regions which can be used in transport codes.

  19. THE ALGOL TRIPLE SYSTEM SPATIALLY RESOLVED AT OPTICAL WAVELENGTHS

    SciTech Connect (OSTI)

    Zavala, R. T.; Hutter, D. J. [U.S. Naval Observatory, Flagstaff Station, 10391 W. Naval Obs. Rd., Flagstaff, AZ 86001 (United States); Hummel, C. A. [European Organization for Astronomical Research in the Southern Hemisphere, Karl-Schwarzschild-Str. 2, 85748 Garching bei Muenchen (Germany); Boboltz, D. A.; Ojha, R. [U.S. Naval Observatory, 3450 Massachusetts Ave. NW, Washington DC 20392 (United States); Shaffer, D. B. [Lowell Observatory, 1400 W. Mars Hill Rd., Flagstaff, AZ 86001 (United States); Tycner, C. [Department of Physics, Central Michigan University, Mt. Pleasant, MI 48859 (United States); Richards, M. T., E-mail: bzavala@nofs.navy.mi, E-mail: djh@nofs.navy.mi, E-mail: chummel@eso.or, E-mail: dboboltz@usno.navy.mi, E-mail: rojha@usno.navy.mi, E-mail: shaffer@alumni.caltech.ed, E-mail: c.tycner@cmich.ed, E-mail: mrichards@astro.psu.ed [Department of Astronomy and Astrophysics, Pennsylvania State University, 525 Davey Lab, University Park, PA 19104 (United States)

    2010-05-20T23:59:59.000Z

    Interacting binaries typically have separations in the milliarcsecond regime, and hence it has been challenging to resolve them at any wavelength. However, recent advances in optical interferometry have improved our ability to discern the components in these systems and have now enabled the direct determination of physical parameters. We used the Navy Prototype Optical Interferometer to produce for the first time images resolving all three components in the well-known Algol triple system. Specifically, we have separated the tertiary component from the binary and simultaneously resolved the eclipsing binary pair, which represents the nearest and brightest eclipsing binary in the sky. We present revised orbital elements for the triple system, and we have rectified the 180{sup 0} ambiguity in the position angle of Algol C. Our directly determined magnitude differences and masses for this triple star system are consistent with earlier light curve modeling results.

  20. Gasoline prices decrease (Short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name:24, 2014 Gasoline pricesGasolineShort

  1. SHORT-TERM EVOLUTION OF CORONAL HOLE BOUNDARIES

    SciTech Connect (OSTI)

    Krista, Larisza D.; Gallagher, Peter T.; Bloomfield, D. Shaun [Astrophysics Research Group, School of Physics, Trinity College Dublin, Dublin 2 (Ireland)

    2011-04-20T23:59:59.000Z

    The interaction of open and closed field lines at coronal hole (CH) boundaries is widely accepted to be due to interchange magnetic reconnection. To date, it is unclear how the boundaries vary on short timescales and at what velocity this occurs. Here, we describe an automated boundary tracking method used to determine CH boundary displacements on short timescales. The boundary displacements were found to be isotropic and to have typical expansion/contraction speeds of {<=}2 km s{sup -1}, which indicate magnetic reconnection rates of {<=}3 x 10{sup -3}. The observed displacements were used in conjunction with the interchange reconnection model to derive typical diffusion coefficients of {<=}3 x 10{sup 13} cm{sup 2} s{sup -1}. These results are consistent with an interchange reconnection process in the low corona driven by the random granular motions of open and closed fields in the photosphere.

  2. Rare-gas-cluster explosions under irradiation by intense short XUV pulses

    SciTech Connect (OSTI)

    Hoffmann, K.; Murphy, B.; Kandadai, N.; Erk, B.; Helal, A.; Keto, J.; Ditmire, T. [Department of Physics, Texas Center for High Intensity Laser Science, University of Texas at Austin, Austin, Texas 78712 (United States)

    2011-04-15T23:59:59.000Z

    High-intensity, extreme-ultraviolet (XUV) femtosecond interactions with large rare-gas clusters of xenon and argon have been studied at a wavelength of 38 nm. Pulses of XUV radiation with nJ energy are produced by high-order harmonic conversion from a 35-fs, near-infrared, terawatt laser. Mass resolved ion spectra show charge states up to Xe{sup 8+} and Ar{sup 4+}. Kinetic-energy measurements of ions and electrons indicate that a nanoplasma is formed and a hydrodynamic cluster explosion ensues after heating by the short wavelength pulse. It appears that the observed charge states and electron temperatures are consistent with sequential, single-photon ionization and collisional ionization of ions that have had their ionization potential depressed by plasma continuum lowering in the cluster nanoplasma.

  3. SHORT DYNAMIC FIBRILS IN SUNSPOT CHROMOSPHERES

    SciTech Connect (OSTI)

    Rouppe van der Voort, L. [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, N-0315 Oslo (Norway); De la Cruz Rodríguez, J. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala (Sweden)

    2013-10-10T23:59:59.000Z

    Sunspot chromospheres display vigorous oscillatory signatures when observed using chromospheric diagnostics such as the strong Ca II lines and H?. New high-resolution sunspot observations from the Swedish 1 m Solar Telescope show the ubiquitous presence of small-scale, periodic, jet-like features that move up and down. This phenomenon has not been described before. The typical width of these features is about 0.''3 and they display clear parabolic trajectories in space-time diagrams. The maximum extension of the top of the jets is lowest in the umbra, a few 100 km, and progressively longer further away from the umbra in the penumbra, with the longest extending more than 1000 km. These jets resemble the dynamic fibrils found in plage regions but at smaller extensions. Local thermodynamic equilibrium inversion of spectropolarimetric Ca II 8542 observations enabled a comparison of the magnetic field inclination and properties of these short jets. We find that the most extended of these jets also have longer periods and tend to be located in regions with more horizontal magnetic fields. These results are direct observational confirmation of the mechanism of long-period waves propagating along inclined magnetic fields into the solar chromosphere. This mechanism was identified earlier as the driver of dynamic fibrils in plage, part of the mottles in the quiet Sun, and the type I spicules at the limb. The sunspot dynamic fibrils that we report here represent a new class of manifestation of this mechanism, distinct from the transient penumbral and umbral micro-jets reported earlier.

  4. Drop short control of electrode gap

    DOE Patents [OSTI]

    Fisher, Robert W. (Albuquerque, NM); Maroone, James P. (Albuquerque, NM); Tipping, Donald W. (Albuquerque, NM); Zanner, Frank J. (Sandia Park, NM)

    1986-01-01T23:59:59.000Z

    During vacuum consumable arc remelting the electrode gap between a consumable electrode and a pool of molten metal is difficult to control. The present invention monitors drop shorts by detecting a decrease in the voltage between the consumable electrode and molten pool. The drop shorts and their associated voltage reductions occur as repetitive pulses which are closely correlated to the electrode gap. Thus, the method and apparatus of the present invention controls electrode gap based upon drop shorts detected from the monitored anode-cathode voltage. The number of drop shorts are accumulated, and each time the number of drop shorts reach a predetermined number, the average period between drop shorts is calculated from this predetermined number and the time in which this number is accumulated. This average drop short period is used in a drop short period electrode gap model which determines the actual electrode gap from the drop short. The actual electrode gap is then compared with a desired electrode gap which is selected to produce optimum operating conditions and the velocity of the consumable error is varied based upon the gap error. The consumable electrode is driven according to any prior art system at this velocity. In the preferred embodiment, a microprocessor system is utilized to perform the necessary calculations and further to monitor the duration of each drop short. If any drop short exceeds a preset duration period, the consumable electrode is rapidly retracted a predetermined distance to prevent bonding of the consumable electrode to the molten remelt.

  5. Zeiss-Meta -1-Short instructions Short instructions for the Zeiss-META

    E-Print Network [OSTI]

    Manstein, Dietmar J.

    #12;Zeiss-Meta -2- Short instructions 1. Laser safety Safety notes for operating the laser scanningZeiss-Meta -1- Short instructions Short instructions for the Zeiss-META Version 080708 This short information on laser safety and general guidelines. Content: 1. Laser safety Page 2 2. General guidelines Page

  6. Olympus FV1000 -1-Short instructions Short instructions. Olympus FV1000

    E-Print Network [OSTI]

    Manstein, Dietmar J.

    the microscope Page 7 #12;Olympus FV1000 -2- Short instructions 1. Laser safety Safety notes for operatingOlympus FV1000 -1- Short instructions Short instructions. Olympus FV1000 Version 110608 This short information on laser safety and general guidelines. Content: 1. Laser safety Page 2 2. General guidelines Page

  7. Olympus FV1000 -1-Short instructions Short instructions. Olympus FV1000

    E-Print Network [OSTI]

    Manstein, Dietmar J.

    the microscope Page 7 #12;Olympus FV1000 -2- Short instructions 1. Laser safety Safety notes for operatingOlympus FV1000 -1- Short instructions Short instructions. Olympus FV1000 Version 140416 This short information on laser safety and general guidelines. Content: 1. Laser safety Page 2 2. General guidelines Page

  8. Development of in situ, at-wavelength metrology for soft x-ray nano-focusing

    SciTech Connect (OSTI)

    Yuan, Sheng Sam; Yashchuk, Valeriy V.; Goldberg, Kenneth A.; Celestre, Richard; McKinney, Wayne R.; Morrison, Gregory Y.; Warwick, Tony; Padmore, Howard A.

    2010-09-19T23:59:59.000Z

    At the Advanced Light Source (ALS), we are developing broadly applicable, high-accuracy, in situ, at-wavelength wavefront slope measurement techniques for Kirkpatrick-Baez (KB) mirror nano-focusing. We describe here details of the metrology beamline endstation, the at-wavelength tests, and an original alignment method that have already allowed us to precisely set a bendable KB mirror to achieve a FWHM focused spot size of ~;;120 nm, at 1-nm soft x-ray wavelength.

  9. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    SciTech Connect (OSTI)

    Hau-Riege, S; London, R A; Bionta, R M; McKernan, M A; Baker, S L; Krzywinski, J; Sobierajski, R; Nietubyc, R; Pelka, J B; Jurek, M; Klinger, D; Juha, L; Chalupsky, J; Cihelka, J; Hajkova, V; Koptyaev, S; Velyhan, A; Krasa, J; Kuba, J; Tiedtke, K; Toleikis, S; Tschentscher, T; Wabnitz, H; Bergh, M; Caleman, C; Sokolowski-Tinten, K; Stojanovic, N; Zastrau, U; Tronnier, A; Meyer-ter-Vehn, J

    2007-12-03T23:59:59.000Z

    We exposed samples of B4C, amorphous C, chemical-vapor-deposition (CVD)-diamond C, Si, and SiC to single 25 fs-long pulses of 32.5 nm free-electron-laser radiation at fluences of up to 2.2 J/cm{sup 2}. The samples were chosen as candidate materials for x-ray free electron laser (XFEL) optics. We found that the threshold for surface-damage is on the order of the fluence required for thermal melting. For larger fluences, the crater depths correspond to temperatures on the order of the critical temperature, suggesting that the craters are formed by two-phase vaporization [1]. XFELs have the promise of producing extremely high-intensity ultrashort pulses of coherent, monochromatic radiation in the 1 to 10 keV regime. The expected high output fluence and short pulse duration pose significant challenges to the optical components, including radiation damage. It has not been possible to obtain direct experimental verification of the expected damage thresholds since appropriate x-ray sources are not yet available. FLASH has allowed us to study the interaction of high-fluence short-duration photon pulses with materials at the shortest wavelength possible to date. With these experiments, we have come closer to the extreme conditions expected in XFEL-matter interaction scenarios than previously possible.

  10. Polarization operator approach to pair creation in short laser pulses

    E-Print Network [OSTI]

    Meuren, Sebastian; Keitel, Christoph H; Di Piazza, Antonino

    2014-01-01T23:59:59.000Z

    We investigate the nonlinear Breit-Wheeler process inside short laser pulses, i.e. the creation of an electron-positron pair induced by a gamma photon inside a plane-wave background field. To obtain the total pair-creation probability we verify (to leading-order) the cutting rule for the polarization operator in the realm of strong-field QED by an explicit calculation. Furthermore, a double-integral representation for the leading-order contribution to the field-dependent part of the polarization operator is derived. The combination of both results yields a compact expression for the total pair-creation probability inside an arbitrary plane-wave background field. It is shown numerically that with presently available technology pair-creation probabilities of the order of ten percent could be reached for a single gamma photon.

  11. Magic wavelengths for the $5s-18s$ transition in rubidium

    E-Print Network [OSTI]

    E. A. Goldschmidt; D. G. Norris; S. B. Koller; R. Wyllie; R. C. Brown; J. V. Porto; U. I. Safronova; M. S. Safronova

    2015-03-10T23:59:59.000Z

    Magic wavelengths, for which there is no differential ac Stark shift for the ground and excited state of the atom, allow trapping of excited Rydberg atoms without broadening the optical transition. This is an important tool for implementing quantum gates and other quantum information protocols with Rydberg atoms, and reliable theoretical methods to find such magic wavelengths are thus extremely useful. We use a high-precision all-order method to calculate magic wavelengths for the $5s-18s$ transition of rubidium, and compare the calculation to experiment by measuring the light shift for atoms held in an optical dipole trap at a range of wavelengths near a calculated magic value.

  12. A multi-crystal wavelength dispersive x-ray spectrometer

    SciTech Connect (OSTI)

    Alonso-Mori, Roberto; Montanez, Paul; Delor, James; Bergmann, Uwe [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Kern, Jan [LCLS, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States); Sokaras, Dimosthenis; Weng, Tsu-Chien; Nordlund, Dennis [SSRL, SLAC National Accelerator Laboratory, Menlo Park, California 94025 (United States); Tran, Rosalie; Yachandra, Vittal K.; Yano, Junko [Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720-8099 (United States)

    2012-07-15T23:59:59.000Z

    A multi-crystal wavelength dispersive hard x-ray spectrometer with high-energy resolution and large solid angle collection is described. The instrument is specifically designed for time-resolved applications of x-ray emission spectroscopy (XES) and x-ray Raman scattering (XRS) at X-ray Free Electron Lasers (XFEL) and synchrotron radiation facilities. It also simplifies resonant inelastic x-ray scattering (RIXS) studies of the whole 2d RIXS plane. The spectrometer is based on the Von Hamos geometry. This dispersive setup enables an XES or XRS spectrum to be measured in a single-shot mode, overcoming the scanning needs of the Rowland circle spectrometers. In conjunction with the XFEL temporal profile and high-flux, it is a powerful tool for studying the dynamics of time-dependent systems. Photo-induced processes and fast catalytic reaction kinetics, ranging from femtoseconds to milliseconds, will be resolvable in a wide array of systems circumventing radiation damage.

  13. Digital Frequency Domain Multiplexer for mm-Wavelength Telescopes

    SciTech Connect (OSTI)

    Spieler, Helmuth G; Dobbs, Matt; Bissonnette, Eric; Spieler, Helmuth G.

    2007-07-23T23:59:59.000Z

    An FPGA based digital signal processing (DSP) system for biasing and reading out multiplexed bolometric detectors for mm-wavelength telescopes is presented. This readout system is being deployed for balloon-borne and ground based cosmology experiments with the primary goal of measuring the signature of inflation with the Cosmic Microwave Background Radiation. The system consists of analog superconducting electronics running at 250 mK and 4 K, coupled to digital room temperature backend electronics described here. The digital electronics perform the real time functionality with DSP algorithms implemented in firmware. A soft embedded processor provides all of the slow housekeeping control and communications. Each board in the system synthesizes multi-frequency combs of 8 to 32 carriers in the MHz band to bias the detectors. After the carriers have been modulated with the sky-signal by the detectors, the same boards digitize the comb directly. The carriers are mixed down to base-band and low pass filtered. The signal bandwidth of 0.050Hz-100 Hz places extreme requirements on stability and requires powerful filtering techniques to recover the sky-signal from the MHz carriers.

  14. Multi-wavelength identification of high-energy sources

    E-Print Network [OSTI]

    Mignani, R P

    2009-01-01T23:59:59.000Z

    The nature of most of the ~300 high-energy gamma-ray sources discovered by the EGRET instrument aboard the Gamma-ray Observatory (GRO) between 1991 and 1999 is one of the greatest enigmas in high-energy astrophysics. While about half of the extragalactic sources have been optically identified with Active Galactic Nuclei (AGN), only a meagre 10% of the galactic sources have a reliable identification. This low success rate has mainly to be ascribed to the local crowding of potential optical counterparts and to the large gamma-ray error boxes (of the order of one degree in radius) which prevented a straightforward optical identification. Indeed, a multi-wavelength identification strategy, based on a systematic coverage of the gamma-ray error boxes, has been the only do-able approach. The situation is now greatly improving thanks to the observations performed by the Fermi Gamma-ray Space Telescope which, thanks to the LAT instrument, provides a factor of 50 improvement in sensitivity and a factor of 10 improvemen...

  15. At-wavelength Optical Metrology Development at the ALS

    SciTech Connect (OSTI)

    Yuan, Sheng Sam; Goldberg, Kenneth A.; Yashchuk, Valeriy V.; Celestre, Richard; Mochi, Iacopo; Macdougall, James; Morrison, Gregory Y.; Smith, Brian V.; Domning, Edward E.; McKinney, Wayne R.; Warwick, Tony

    2010-07-19T23:59:59.000Z

    Nano-focusing and brightness preservation for ever brighter synchrotron radiation and free electron laser beamlines require surface slope tolerances of x-ray optics on the order of 100 nrad. While the accuracy of fabrication and ex situ metrology of x-ray mirrors has improved over time, beamline in situ performance of the optics is often limited by application specific factors such as x-ray beam heat loading, temperature drift, alignment, vibration, etc. In the present work, we discuss the recent results from the Advanced Light Source developing high accuracy, in situ, at-wavelength wavefront measurement techniques to surpass 100-nrad accuracy surface slope measurements with reflecting x-ray optics. The techniques will ultimately allow closed-loop feedback systems to be implemented for x-ray nano-focusing. In addition, we present a dedicated metrology beamline endstation, applicable to a wide range of in situ metrology and test experiments. The design and performance of a bendable Kirkpatrick-Baez (KB) mirror with active temperature stabilization will also be presented. The mirror is currently used to study, refine, and optimize in situ mirror alignment, bending and metrology methods essential for nano-focusing application.

  16. Wavelength-encoded optical psychrometer for relative humidity measurement

    SciTech Connect (OSTI)

    Montanini, Roberto [Department of Industrial Chemistry and Materials Engineering, University of Messina, I-98166 Messina (Italy)

    2007-02-15T23:59:59.000Z

    In this article an optical psychrometer, in which temperature measurements are performed by means of two fiber Bragg grating sensors used as dry-bulb and wet-bulb thermometers, is introduced. The adopted design exploits both the high accuracy of psychrometric-based relative humidity measurements with acknowledged advantages of wavelength-encoded fiber optic sensing. Important metrological issues that have been addressed in the experimental work include calibration of the fiber Bragg grating temperature sensors, evaluation of response time, sensitivity, hysteresis, linearity, and accuracy. The calibration results give confidence that, with the current experimental setup, measurement of temperature can be done with an uncertainty of {+-}0.2 deg. C and a resolution of 0.1 deg. C. A detailed uncertainty analysis is also presented in the article to investigate the effects produced by different sources of error on the combined standard uncertainty u{sub c}(U) of the relative humidity measurement, which has been estimated to be roughly within {+-}2% in the range close to saturation.

  17. ANNOUNCEMENT Short-Term Course

    E-Print Network [OSTI]

    Srivastava, Kumar Vaibhav

    to reduction in underground-based carbon resources. This has propelled the development of advanced engine-treatment such as selective catalyst reduction and NOx storage catalysts · Oxidation catalysts for VOC, and hydrocarbon-2). There will be a book exhibition on one evening. The first day of the course i.e. 28th June will be for the field visit

  18. ANNOUNCEMENT Short-Term Course

    E-Print Network [OSTI]

    Srivastava, Kumar Vaibhav

    to reduction in underground-based carbon resources. This has propelled the development of advanced engine traps · Selective catalytic reduction technique · NOx storage catalysts · engine system strategies will be for the field visit to Engine Development Directorate, RDSO Lucknow, Ministry of Railways (Not compulsory

  19. ANNOUNCEMENT Short-Term Course

    E-Print Network [OSTI]

    Srivastava, Kumar Vaibhav

    to reduction in underground- based carbon resources. This has propelled the development of advanced engine traps · Selective catalytic reduction technique · NOx storage catalysts · engine system strategies will be for the field visit to Engine Development Directorate, RDSO Lucknow, Ministry of Railways (Not compulsory

  20. SHORT COMMUNICATION: LARGER CLIQUES FOR A DIMACS ...

    E-Print Network [OSTI]

    SHORT COMMUNICATION: LARGER CLIQUES FOR A. DIMACS TEST. A. GROSSO, M. LOCATELLI, W. J. PULLAN. 1. The new cliques. DIMACS benchmarks ...

  1. Cosmic Electromagnetic Fields due to Perturbations in the Gravitational Field

    E-Print Network [OSTI]

    Bishop Mongwane; Peter K. S. Dunsby; Bob Osano

    2012-10-21T23:59:59.000Z

    We use non-linear gauge-invariant perturbation theory to study the interaction of an inflation produced seed magnetic field with density and gravitational wave perturbations in an almost Friedmann-Lema\\^itre-Robertson-Walker (FLRW) spacetime. We compare the effects of this coupling under the assumptions of poor conductivity, infinite conductivity and the case where the electric field is sourced via the coupling of velocity perturbations to the seed field in the ideal magnetohydrodynamic (MHD) regime, thus generalizing, improving on and correcting previous results. We solve our equations for long wavelength limits and numerically integrate the resulting equations to generate power spectra for the electromagnetic field variables, showing where the modes cross the horizon. We find that the rotation of the electric field dominates the power spectrum on small scales, in agreement with previous arguments.

  2. Constraint Satisfaction in Optical Routing for Passive Wavelength-Routed Networks

    E-Print Network [OSTI]

    California at Davis, University of

    ). Latin Routers are attractive for optical network design because of their fault-tolerance and low costConstraint Satisfaction in Optical Routing for Passive Wavelength-Routed Networks Dhritiman of lightpaths in an optical network, which employs a passive wavelength routing device called a Latin Router (LR

  3. Dynamic Non-Continuous Single Slot Advance Reservation over Wavelength Routed Networks

    E-Print Network [OSTI]

    Dynamic Non-Continuous Single Slot Advance Reservation over Wavelength Routed Networks Bharath H) requests in all- optical wavelength division multiplexed (WDM) networks. We propose a two-phase novel signaling in the network by reducing the average number of lightpath switches significantly and greatly

  4. Dry friction between laser-patterned surfaces: Role of alignment, structural wavelength and

    E-Print Network [OSTI]

    Mueser, Martin

    1 Dry friction between laser-patterned surfaces: Role of alignment, structural wavelength.gachot@mx.uni-saarland.de Abstract The ability to tune friction by tailoring surface topographies at micron length scales friction between laser-textured surfaces. Line-like laser patterns with varying structural wavelengths

  5. Development and operation of a high-throughput accurate-wavelength lens-based spectrometera)

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

    Bell, Ronald E.

    2014-11-01T23:59:59.000Z

    A high-throughput spectrometer for the 400-820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm-1 grating is matched with fast f /1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy more »wavelength calibration.« less

  6. 832 OPTICS LETTERS / Vol. 25, No. 11 / June 1, 2000 Simultaneous optical wavelength interchange with a

    E-Print Network [OSTI]

    Sheridan, Jennifer

    832 OPTICS LETTERS / Vol. 25, No. 11 / June 1, 2000 Simultaneous optical wavelength interchange January 21, 2000 We present a theoretical analysis for simultaneous optical wavelength interchange and isolation of a pair of collinear input optical signals by use of two concurrent difference

  7. Wavelength attack on practical continuous-variable quantum-key-distribution system with a heterodyne protocol

    E-Print Network [OSTI]

    Xiang-Chun Ma; Shi-Hai Sun; Mu-Sheng Jiang; Lin-Mei Liang

    2014-03-04T23:59:59.000Z

    We present the wavelength attack on a practical continuous-variable quantum-key-distribution system with a heterodyne protocol, in which the transmittance of beam splitters at Bob's station is wavelength-dependent. Our strategy is proposed independent of but analogous to that of Huang et al. [arXiv: 1206.6550v1 [quant-ph

  8. Multicast Routing and Wavelength Assignment in WDM Mesh Networks with Sparse Splitting

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    separately by heuristic algorithms, or formulated as an Integer Linear Programming (ILP) and solved onceMulticast Routing and Wavelength Assignment in WDM Mesh Networks with Sparse Splitting Fen Zhou.cousin@irisa.fr Abstract--In this paper routing and wavelength assignment for supporting multicast traffic is investigated

  9. Wavelength Assignment to Minimize the Number of SONET ADMs in WDM Rings

    E-Print Network [OSTI]

    Yuan, Xin

    an integer linear programming (ILP) forma- tion for this problem, propose a new wavelength assignment to minimize the number of SONET ADMs is NP­hard. In this paper, we develop an in- teger linear programmingWavelength Assignment to Minimize the Number of SONET ADMs in WDM Rings Xin Yuan Amit Fulay

  10. December 2001 LIDS REPORT P-2535 Routing and Wavelength Assignment in

    E-Print Network [OSTI]

    Bertsekas, Dimitri

    - linear programming formulations, which can be addressed with highly efficient linear (not integerDecember 2001 LIDS REPORT P-2535 Routing and Wavelength Assignment in Optical Networks 1 by Asuman E. Ozdaglar and Dimitri P. Bertsekas 2 Abstract The problem of routing and wavelength assignment

  11. Metal slit array Fresnel lens for wavelength-scale optical coupling to nanophotonic waveguides

    E-Print Network [OSTI]

    Park, Namkyoo

    Metal slit array Fresnel lens for wavelength-scale optical coupling to nanophotonic waveguides a novel metal slit array Fresnel lens for wavelength- scale optical coupling into a nanophotonic waveguide. Using the plasmonic waveguide structure in Fresnel lens form, a much wider beam acceptance angle

  12. Convective heat transfer as a function of wavelength: Implications for the cooling of the Earth

    E-Print Network [OSTI]

    Convective heat transfer as a function of wavelength: Implications for the cooling of the Earth C, in particular, on its variation with the wavelength of convection. The heat transfer strongly depends in Earth's mantle can significantly reduce the efficiency of heat transfer. The likely variations

  13. A Wavelength-Tunable Monolithically Integrated Double Ring Resonator Coupled Laser

    E-Print Network [OSTI]

    and require an additional epitaxial growth step [8]. The 300 µm SOA sections are not biased and absorb to 30 nm wavelength tuning of the single-mode lasing. Four Platinum heaters are integrated on the top of microring waveguides. Varying the current of one heater can result the shift of resonance wavelength

  14. Wavelength dependence of prepulse laser beams on EUV emission from CO2 reheated Sn plasma

    E-Print Network [OSTI]

    Harilal, S. S.

    Wavelength dependence of prepulse laser beams on EUV emission from CO2 reheated Sn plasma J. R. The expanding plume was then reheated by a 35 ns CO2 laser operating at 10.6 m. The role of prepulse wavelength, Tanaka et al.11 demonstrated the advantages of using a CO2 laser for generating higher CE. The CO2 LPP

  15. Laser warning receiver to identify the wavelength and angle of arrival of incident laser light

    DOE Patents [OSTI]

    Sinclair; Michael B. (Albuquerque, NM); Sweatt, William C. (Albuquerque, NM)

    2010-03-23T23:59:59.000Z

    A laser warning receiver is disclosed which has up to hundreds of individual optical channels each optically oriented to receive laser light from a different angle of arrival. Each optical channel has an optical wedge to define the angle of arrival, and a lens to focus the laser light onto a multi-wavelength photodetector for that channel. Each multi-wavelength photodetector has a number of semiconductor layers which are located in a multi-dielectric stack that concentrates the laser light into one of the semiconductor layers according to wavelength. An electrical signal from the multi-wavelength photodetector can be processed to determine both the angle of arrival and the wavelength of the laser light.

  16. The All-Wavelength Extended Groth Strip International Survey(AEGIS) Data Sets

    SciTech Connect (OSTI)

    Davis, M.; Guhathakurta, P.; Konidaris, N.P.; Newman, J.A.; Ashby, M.L.N.; Biggs, A.D.; Barmby, P.; Bundy, K.; Chapman, S.C.; Coil,A.L.; Conselice, C.J.; Cooper, M.C.; Croton, D.J.; Eisenhardt, P.R.M.; Ellis, R.S.; Faber, S.M.; Fang, T.; Fazio, G.G.; Georgakakis, A.; Gerke,B.F.; Goss, W.M.; Gwyn, S.; Harker, J.; Hopkins, A.M.; Huang, J.-S.; Ivison, R.J.; Kassin, S.A.; Kirby, E.N.; Koekemoer, A.M.; Koo, D.C.; Laird, E.S.; Le Floc'h, E.; Lin, L.; Lotz, J.M.; Marshall, P.J.; Martin,D.C.; Metevier, A.J.; Moustakas, L.A.; Nandra, K.; Noeske, K.G.; Papovich, C.; Phillips, A.C.; Rich,R. M.; Rieke, G.H.; Rigopoulou, D.; Salim, S.; Schiminovich, D.; Simard, L.; Smail, I.; Small,T.A.; Weiner,B.J.; Willmer, C.N.A.; Willner, S.P.; Wilson, G.; Wright, E.L.; Yan, R.

    2006-10-13T23:59:59.000Z

    In this the first of a series of Letters, we present a description of the panchromatic data sets that have been acquired in the Extended Groth Strip region of the sky. Our survey, the All-wavelength Extended Groth Strip International Survey (AEGIS), is intended to study the physical properties and evolutionary processes of galaxies at z{approx}1. It includes the following deep, wide-field imaging data sets: Chandra/ACIS X-ray (0.5-10 keV), GALEX ultraviolet (1200-2500 Angstroms), CFHT/MegaCam Legacy Survey optical (3600-9000 Angstroms), CFHT/CFH12K optical (4500-9000 Angstroms), Hubble Space Telescope/ACS optical (4400-8500 Angstroms), Palomar/WIRC near-infrared (1.2-2.2 {micro}m), Spitzer/IRAC mid-infrared (3.6-8.0 {micro}m), Spitzer/MIPS far-infrared (24-70 {micro}m), and VLA radio continuum (6-20 cm). In addition, this region of the sky has been targeted for extensive spectroscopy using the DEIMOS spectrograph on the Keck II 10 m telescope. Our survey is compared to other large multiwavelength surveys in terms of depth and sky coverage.

  17. The All-wavelength Extended Groth Strip International Survey (AEGIS) Data Sets

    SciTech Connect (OSTI)

    Davis, M.; Guhathakurta, P.; Konidaris, N.; Newman, J.A.; Ashby, M.L.N.; Biggs, A.D.; Barmby, P.; Bundy, K.; Chapman, S.; Coil, A.L.; Conselice, C.; Cooper, M.; Croton,; Eisenhardt, P.; Ellis, R.; Faber, S.; Fang, T.; Fazio, G.G.; Georgakakis, A.; Gerke, B.; Goss, W.M.; /UC, Berkeley, Astron. Dept. /Lick Observ. /LBL, Berkeley

    2006-07-21T23:59:59.000Z

    In this the first of a series of ''Letters'', we present a description of the panchromatic data sets that have been acquired in the Extended Groth Strip region of the sky. Our survey, the All-wavelength Extended Groth Strip International Survey (AEGIS), is intended to study the physical properties and evolutionary processes of galaxies at z {approx} 1. It includes the following deep, wide-field imaging data sets: Chandra/ACIS{sup 30} X-ray (0.5-10 keV), GALEX{sup 31} ultraviolet (1200-2500 A), CFHT/MegaCam Legacy Survey{sup 32} optical (3600-9000 {angstrom}), CFHT/CFH12K optical (4500-9000 {angstrom}), Hubble Space Telescope/ACS{sup 33} optical (4400-8500 {angstrom}), Palomar/WIRC{sup 34} near-infrared (1.2-2.2 {micro}m), Spitzer/IRAC{sup 35} mid-infrared (3.6-8.0 {micro}m), Spitzer/MIPS far-infrared (24-70 {micro}m), and VLA{sup 36} radio continuum (6-20 cm). In addition, this region of the sky has been targeted for extensive spectroscopy using the DEIMOS spectrograph on the Keck II 10 m telescope{sup 37}. Our survey is compared to other large multiwavelength surveys in terms of depth and sky coverage.

  18. Short-time Dynamics of Frictional Strength in Dry Friction O. Ben-David, G. Cohen and J. Fineberg

    E-Print Network [OSTI]

    Fineberg, Jay

    Short-time Dynamics of Frictional Strength in Dry Friction O. Ben-David, G. Cohen and J. Fineberg interface that separates two PMMA blocks in dry frictional contact. At applied shear forces significantly weakening 1. Introduction The short-time dynamics of dry friction are of fundamental interest in fields

  19. Short-time Dynamics of Frictional Strength in Dry Friction O. Ben-David and J. Fineberg

    E-Print Network [OSTI]

    Fineberg, Jay

    Short-time Dynamics of Frictional Strength in Dry Friction O. Ben-David and J. Fineberg The Racah that separates two PMMA blocks in dry frictional contact. At applied shear forces significantly below the static The short-time dynamics of dry friction are of fundamental interest in fields ranging from hard drive disk

  20. Title of Dissertation: A Search for Short Duration Very High Energy Emission from Gamma-Ray Bursts

    E-Print Network [OSTI]

    California at Santa Cruz, University of

    of GRBs. #12;A Search for Short Duration Very High Energy Emission from Gamma-Ray Bursts by David NoyesABSTRACT Title of Dissertation: A Search for Short Duration Very High Energy Emission from Gamma-Ray by gamma rays with primary energies of approximately 100 GeV and higher. The wide field of view ( 2 sr

  1. Shielding, Levitation, Propulsion G. W. Jewell, Chariman Method for expanding the uniformly shielded area in a short-length

    E-Print Network [OSTI]

    Paperno, Eugene

    Shielding, Levitation, Propulsion G. W. Jewell, Chariman Method for expanding the uniformly shielded area in a short-length open-ended cylindrical magnetic shield K. Oshita, I. Sasada,a) H. Naka shielded area of the axial magnetic field in a relatively short, open-structure axial magnetic shield can

  2. Configurations for short period rf undulators

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

    Kuzikov, S. V.; Jiang, Y.; Marshall, T. C.; Sotnikov, G. V.; Hirshfield, J. L.

    2013-07-01T23:59:59.000Z

    Several configurations for rf undulators energized at millimeter wavelengths and designed to produce coherent nanometer radiation from sub-GeV electron beams are analyzed and compared with one another. These configurations include a traveling-wave resonant ring, a standing wave resonator, and a resonator operating close to cutoff.

  3. Round Mountain Field, Short Radius Lateral Drilling in the Vedder Sand Round Mountain Field, California

    SciTech Connect (OSTI)

    Chenot P.E., David W.

    2002-03-10T23:59:59.000Z

    A 3-D simulation model study was run using CMG's STARS thermal model, and showed that a 122 meter (400 foot) horizontal well should produce up to 64 cubic meters per day of oil (400 B/D) when the heated oil bank hits the well.

  4. Efficient Wavelength Tuning Techniques for Integrated Silicon Photonics

    E-Print Network [OSTI]

    Titriku, Alex K

    2014-12-04T23:59:59.000Z

    for the degree of MASTER OF SCIENCE Chair of Committee, Samuel Palermo Committee Members, Edgar Sanchez-Sinencio Krishna Narayanan Yoonsuck Choe Head of Department, Chanan Singh December 2014 Major Subject: Electrical Engineering Copyright 2014 Alex Kwasi Nyavor... for agreeing to be my advisor and giving me the opportunity to contribute to this exciting field of silicon photonics. In addition to his excellent mentorship and insight, he continuously challenges me to give my best output. I also sincerely thank Dr. Edgar...

  5. MULTI-WAVELENGTH RADIO CONTINUUM EMISSION STUDIES OF DUST-FREE RED GIANTS

    SciTech Connect (OSTI)

    O'Gorman, Eamon; Harper, Graham M. [School of Physics, Trinity College Dublin, Dublin 2 (Ireland); Brown, Alexander [Center for Astrophysics and Space Astronomy, University of Colorado, 389 UCB, Boulder, CO 80309 (United States); Drake, Stephen [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Richards, Anita M. S. [Jodrell Bank Centre for Astrophysics, School of Physics and Astronomy, University of Manchester, Manchester M13 9PL (United Kingdom)

    2013-10-01T23:59:59.000Z

    Multi-wavelength centimeter continuum observations of non-dusty, non-pulsating K spectral-type red giants directly sample their chromospheres and wind acceleration zones. Such stars are feeble emitters at these wavelengths, however, and previous observations have provided only a small number of modest signal-to-noise measurements slowly accumulated over three decades. We present multi-wavelength Karl G. Jansky Very Large Array thermal continuum observations of the wind acceleration zones of two dust-free red giants, Arcturus (? Boo: K2 III) and Aldebaran (? Tau: K5 III). Importantly, most of our observations of each star were carried out over just a few days, so that we obtained a snapshot of the different stellar atmospheric layers sampled at different wavelengths, independent of any long-term variability. We report the first detections at several wavelengths for each star including a detection at 10 cm (3.0 GHz: S band) for both stars and a 20 cm (1.5 GHz: L band) detection for ? Boo. This is the first time single (non-binary) luminosity class III red giants have been detected at these continuum wavelengths. Our long-wavelength data sample the outer layers of ? Boo's atmosphere where its wind velocity is approaching (or possibly has reached) its terminal value and the ionization balance is becoming frozen-in. For ? Tau, however, our long-wavelength data are still sampling its inner atmosphere, where the wind is still accelerating probably due to its lower mass-loss rate. We compare our data with published semi-empirical models based on ultraviolet data, and the marked deviations highlight the need for new atmospheric models to be developed. Spectral indices are used to discuss the possible properties of the stellar atmospheres, and we find evidence for a rapidly cooling wind in the case of ? Boo. Finally, we develop a simple analytical wind model for ? Boo based on our new long-wavelength flux measurements.

  6. Wavelength limits for InGaN quantum wells on GaN

    SciTech Connect (OSTI)

    Pristovsek, Markus, E-mail: markus@pristovsek.de [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)] [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom)

    2013-06-17T23:59:59.000Z

    The emission wavelength of coherently strained InGaN quantum wells (QW) is limited by the maximum thickness before relaxation starts. For high indium contents x>40% the resulting wavelength decreases because quantum confinement dominates. For low indium content x<40% the electron hole wave function overlap (and hence radiative emission) is strongly reduced with increasing QW thickness due to the quantum confined Stark effect and imposes another limit. This results in a maximum usable emission wavelength at around 600?nm for QWs with 40%-50% indium content. Relaxed InGaN buffer layers could help to push this further, especially on non- and semi-polar orientations.

  7. Short-Distance Structure of Nuclei

    E-Print Network [OSTI]

    D. W. Higinbotham; E. Piasetzky; S. A. Wood

    2009-08-02T23:59:59.000Z

    One of Jefferson Lab's original missions was to further our understanding of the short-distance structure of nuclei. In particular, to understand what happens when two or more nucleons within a nucleus have strongly overlapping wave-functions; a phenomena commonly referred to as short-range correlations. Herein, we review the results of the (e,e'), (e,e'p) and (e,e'pN) reactions that have been used at Jefferson Lab to probe this short-distance structure as well as provide an outlook for future experiments.

  8. Wavelength-tunable colloidal quantum dot laser on ultra-thin flexible glass

    SciTech Connect (OSTI)

    Foucher, C.; Guilhabert, B.; Laurand, N.; Dawson, M. D. [Institute of Photonics, SUPA, University of Strathclyde, Glasgow (United Kingdom)

    2014-04-07T23:59:59.000Z

    A mechanically flexible and wavelength-tunable laser with an ultra-thin glass membrane as substrate is demonstrated. The optically pumped hybrid device has a distributed feedback cavity that combines a colloidal quantum dot gain film with a grating-patterned polymeric underlayer, all on a 30-?m thick glass sheet. The total thickness of the structure is only 75??m. The hybrid laser has an average threshold fluence of 450?±?80??J/cm{sup 2} (for 5-ns excitation pulses) at an emitting wavelength of 607?nm. Mechanically bending the thin-glass substrate enables continuous tuning of the laser emission wavelength over an 18-nm range, from 600?nm to 618?nm. The correlation between the wavelength tunability and the mechanical properties of the thin laser structure is verified theoretically and experimentally.

  9. THE STABILITY OF LOW SURFACE BRIGHTNESS DISKS BASED ON MULTI-WAVELENGTH MODELING

    E-Print Network [OSTI]

    MacLachlan, J. M.

    To investigate the structure and composition of the dusty interstellar medium (ISM) of low surface brightness (LSB) disk galaxies, we have used multi-wavelength photometry to construct spectral energy distributions for ...

  10. Sub-wavelength plasmonic readout for direct linear analysis of optically tagged DNA

    E-Print Network [OSTI]

    Varsanik, Jonathan S.

    This work describes the development and fabrication of a novel nanofluidic flow-through sensing chip that utilizes a plasmonic resonator to excite fluorescent tags with sub-wavelength resolution. We cover the design of the ...

  11. Monolithically integrated InP-based tunable wavelength conversion John M. Hutchinson*1

    E-Print Network [OSTI]

    Coldren, Larry A.

    The simplest photocurrent-driven wavelength converter (PD-WC) consists of a photodiode receiver directly such as implemented in the sampled-gating distributed Bragg reflector (SGDBR) laser [10]. A separate DC electrode

  12. Development and operation of a high-throughput accurate-wavelength lens-based spectrometer

    SciTech Connect (OSTI)

    Bell, Ronald E., E-mail: rbell@pppl.gov [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543 (United States)

    2014-11-15T23:59:59.000Z

    A high-throughput spectrometer for the 400–820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm{sup ?1} grating is matched with fast f/1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy ?0.075 arc sec. A high quantum efficiency low-etaloning CCD detector allows operation at longer wavelengths. A patch panel allows input fibers to interface with interchangeable fiber holders that attach to a kinematic mount at the entrance slit. Computer-controlled hardware allows automated control of wavelength, timing, f-number, automated data collection, and wavelength calibration.

  13. Development and Operation of High-throughput Accurate-wavelength Lens-based Spectrometer

    SciTech Connect (OSTI)

    Bell, Ronald E

    2014-07-01T23:59:59.000Z

    A high-throughput spectrometer for the 400-820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm-1 grating is matched with fast f /1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy < 0.075 arc seconds. A high quantum efficiency low-etaloning CCD detector allows operation at longer wavelengths. A patch panel allows input fibers to interface with interchangeable fiber holders that attach to a kinematic mount behind the entrance slit. Computer-controlled hardware allows automated control of wavelength, timing, f-number, automated data collection, and wavelength calibration.

  14. Mitigating of Modal Instabilities in Linearly-Polarized Fiber Amplifiers by Shifting Pump Wavelength

    E-Print Network [OSTI]

    Rumao Tao; Pengfei Ma; Xiaolin Wang; Pu Zhou; Zejin Liu

    2014-12-02T23:59:59.000Z

    We investigated the effct of pump wavelength on the modal instabilities (MI) in high power linearly-polarized Yb-doped fiber amplifiers. We built a novel semi-analytical model to determine the frequency coupling characteristics and power threshold of MI, which indicates promising MI suppression through pumping at an appropriate wavelength. By pumping at 915nm, the threshold can be enhanced by a factor of 2.36 as compared to that pumped at 976nm. Based on a high power linearly-polarized fiber amplifier platform, we studied the influence of pump wavelength experimentally. The threshold has been increased by a factor of 2 at 915nm, which agrees with the theoretical calculation and verified our theoretical model. Furthermore, we show that MI suppression by detuning the pump wavelength is weakened for fiber with large core-to-cladding ratio.

  15. Development of at-wavelength metrology for x-ray optics at the ALS

    E-Print Network [OSTI]

    Yashchuk, Valeriy V.

    2010-01-01T23:59:59.000Z

    alignment of bendable x-ray optics to realize diffraction-Bass (Ed. ), Handbook of Optics, third ed. , vol. V, ch. 46,wavelength metrology for x-ray optics at the ALS* Valeriy V.

  16. Long-Wavelength Local Density of States Oscillations Near Graphene Step Edges

    E-Print Network [OSTI]

    Xue, Jiamin

    Using scanning tunneling microscopy and spectroscopy, we have studied the local density of states (LDOS) of graphene over step edges in boron nitride. Long-wavelength oscillations in the LDOS are observed with maxima ...

  17. Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Cells

    E-Print Network [OSTI]

    Ganapati, Vidya; Yablonovitch, Eli

    2013-01-01T23:59:59.000Z

    Light trapping in solar cells allows for increased current and voltage, as well as reduced materials cost. It is known that in geometrical optics, a maximum 4n^2 absorption enhancement factor can be achieved by randomly texturing the surface of the solar cell, where n is the material refractive index. This ray-optics absorption enhancement limit only holds when the thickness of the solar cell is much greater than the optical wavelength. In sub-wavelength thin films, the fundamental questions remain unanswered: (1) what is the sub-wavelength absorption enhancement limit and (2) what surface texture realizes this optimal absorption enhancement? We turn to computational electromagnetic optimization in order to design nanoscale textures for light trapping in sub-wavelength thin films. For high-index thin films, in the weakly absorbing limit, our optimized surface textures yield an angle- and frequency-averaged enhancement factor ~39. They perform roughly 30% better than randomly textured structures, but they fall...

  18. Narrow band wavelength selective filter using grating assisted single ring resonator

    SciTech Connect (OSTI)

    Prabhathan, P., E-mail: PPrabhathan@ntu.edu.sg; Murukeshan, V. M. [Centre for Optical and Laser Engineering (COLE), School of Mechanical and Aerospace Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2014-09-15T23:59:59.000Z

    This paper illustrates a filter configuration which uses a single ring resonator of larger radius connected to a grating resonator at its drop port to achieve single wavelength selectivity and switching property with spectral features suitable for on-chip wavelength selection applications. The proposed configuration is expected to find applications in silicon photonics devices such as, on-chip external cavity lasers and multi analytic label-free biosensors. The grating resonator has been designed for a high Q-factor, high transmittivity, and minimum loss so that the wavelength selectivity of the device is improved. The proof-of-concept device has been demonstrated on a Silicon-on-Insulator (SOI) platform through electron beam lithography and Reactive Ion Etching (RIE) process. The transmission spectrum shows narrow band single wavelength selection and switching property with a high Free Spectral Range (FSR) ?60 nm and side band rejection ratio >15 dB.

  19. Development and operation of a high-throughput accurate-wavelength lens-based spectrometera)

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

    Bell, Ronald E. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08543, USA

    2014-11-01T23:59:59.000Z

    A high-throughput spectrometer for the 400-820 nm wavelength range has been developed for charge exchange recombination spectroscopy or general spectroscopy. A large 2160 mm-1 grating is matched with fast f /1.8 200 mm lenses, which provide stigmatic imaging. A precision optical encoder measures the grating angle with an accuracy < 0.075 arc seconds. A high quantum efficiency low-etaloning CCD detector allows operation at longer wavelengths. A patch panel allows input fibers to interface with interchangeable fiber holders that attach to a kinematic mount behind the entrance slit. Computer-controlled hardware allows automated control of wavelength, timing, f-number, automated data collection, and wavelength calibration.

  20. Noise Reduction of Centrifugal Compressors using Array of Quarter Wavelength Resonators

    E-Print Network [OSTI]

    Ye, Nan

    2014-07-31T23:59:59.000Z

    compressor is studied, which is aimed to reduce the tonal noise of the compressor. In order to optimally design the quarter-wavelength resonators, numerical simulations are performed by using a commercial software package, COMSOL Multiphysics – Acoustics...

  1. Laser wavelength effects on ionic and atomic emission from tin plasmas D. Campos,a

    E-Print Network [OSTI]

    Harilal, S. S.

    Laser wavelength effects on ionic and atomic emission from tin plasmas D. Campos,a S. S. Harilal centered at 13.5 nm. Spitzer et al.1 reported that tin targets irradiated by a neodymium-doped yttrium alu

  2. Broadly tunable dual-wavelength light source for coherent anti-Stokes Raman scattering

    E-Print Network [OSTI]

    Xie, Xiaoliang Sunney

    by varying the temperature of a single nonlinear crystal. The near-infrared output 900­1300 nm allows reflection R 99% in the idler beam wavelength range. C

  3. Study of Semiconductor Microring Lasers for use in Wavelength Division Multiplexing (WDM)

    E-Print Network [OSTI]

    Kouroupetroglou, Georgios

    Study of Semiconductor Microring Lasers for use in Wavelength Division Multiplexing (WDM of all-active microring resonators as lasers are studied. The structure of a semiconductor microring demonstrated. Keywords: Semiconductor microring lasers, non-linear gain, multimode operation, mode

  4. 12.141 Electron Microprobe Analysis by Wavelength Dispersive X-ray Spectrometry, January (IAP) 2006

    E-Print Network [OSTI]

    Chatterjee, Nilanjan

    Introduction to the theory of x-ray microanalysis through the electron microprobe including ZAF matrix corrections. Techniques to be discussed are wavelength and energy dispersive spectrometry, scanning backscattered ...

  5. Wavelength Tunable Single Nanowire Lasers Based on Surface Plasmon Polariton Enhanced Burstein-Moss Effect

    E-Print Network [OSTI]

    Xiong, Qihua

    -well core/shell NW heterostruc- tures, Qian et al. demonstrated wavelength tunable GaN NW lasers.15 Recently self-absorption of the gain media was also reported.7,16 Parallel to these exciting developments

  6. A PRELIMINARY CALIBRATION OF THE RR LYRAE PERIOD-LUMINOSITY RELATION AT MID-INFRARED WAVELENGTHS: WISE DATA

    SciTech Connect (OSTI)

    Madore, Barry F.; Freedman, Wendy L.; Kollmeier, Juna A.; Monson, Andy; Eric Persson, S.; Rich, Jeff A. Jr.; Scowcroft, Victoria; Seibert, Mark [Observatories of the Carnegie Institution of Washington 813 Santa Barbara Street, Pasadena, CA 91101 (United States); Hoffman, Douglas, E-mail: barry@obs.carnegiescience.edu, E-mail: wendy@obs.carnegiescience.edu, E-mail: jak@obs.carnegiescience.edu, E-mail: amonson@obs.carnegiescience.edu, E-mail: persson@obs.carnegiescience.edu, E-mail: jrich@obs.carnegiescience.edu, E-mail: vs@obs.carnegiescience.edu, E-mail: mseibert@obs.carnegiescience.edu [Infrared Processing and Analysis Center 770 South Wilson, Pasadena, CA 91125 (United States)

    2013-10-20T23:59:59.000Z

    Using time-resolved, mid-infrared data from the Wide-field Infrared Survey Explorer (WISE) and geometric parallaxes from the Hubble Space Telescope for four Galactic RR Lyrae variables, we derive the following Population II period-luminosity (PL) relations for the WISE [W1], [W2], and [W3] bands at 3.4, 4.6, and 12 ?m, respectively: The slopes and the scatter around the fits are consistent with a smooth extrapolation of those same quantities from previously published K-band observations at 2.2 ?m, where the asymptotic (long-wavelength) behavior is consistent with a period-radius relation with a slope of 0.5. No obvious correlation with metallicity (spanning 0.4 dex in [Fe/H]) is found in the residuals of the four calibrating RR Lyrae stars about the mean PL regression line.

  7. Quantum Field Theory in Graphene

    E-Print Network [OSTI]

    I. V. Fialkovsky; D. V. Vassilevich

    2011-11-18T23:59:59.000Z

    This is a short non-technical introduction to applications of the Quantum Field Theory methods to graphene. We derive the Dirac model from the tight binding model and describe calculations of the polarization operator (conductivity). Later on, we use this quantity to describe the Quantum Hall Effect, light absorption by graphene, the Faraday effect, and the Casimir interaction.

  8. NEAR-FIELD IMAGING OF OBSTACLES Peijun Li and Yuliang Wang

    E-Print Network [OSTI]

    2014-06-16T23:59:59.000Z

    In far-field imaging, data is measured at a distance which is a few wavelength or longer away ...... Lastly we examine the effect of the base radius a. In view of.

  9. 8 Short life stories: Dorti Peterson

    E-Print Network [OSTI]

    Leonard, Stephen Pax

    last updated on Monday, 4 April 2011 Accession Form for Individual Recordings: Collection / Collector Name Stephen Leonard Tape No. / Track / Item No. 8 Length of track 33 minutes Title of track Short life stories: Dorti Peterson Translation...

  10. Short-Term Energy Outlook September 2013

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

    day Forecast -0.9 2012 2013 2014 OPEC countries North America Russia and Caspian Sea Latin America North Sea Other Non-OPEC Source: Short-Term Energy Outlook, September 2013 -1...

  11. Laser wavelength effects on the charge state resolved ion energy distributions from laser-produced Sn plasma

    E-Print Network [OSTI]

    Najmabadi, Farrokh

    Laser wavelength effects on the charge state resolved ion energy distributions from laser of laser wavelength on the charge state resolved ion energy distributions from laser-produced Sn plasma freely expanding into vacuum are investigated. Planar Sn targets are irradiated at laser wavelengths

  12. Programmable two-port polarization independent electro-optically tunable wavelength filter in lithium niobate

    E-Print Network [OSTI]

    Ping, Yang

    2009-05-15T23:59:59.000Z

    PROGRAMMABLE TWO-PORT POLARIZATION INDEPENDENT ELECTRO-OPTICALLY TUNABLE WAVELENGTH FILTER IN LITHIUM NIOBATE A Dissertation by YANG PING Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2006 Major Subject: Electrical Engineering PROGRAMMABLE TWO-PORT POLARIZATION INDEPENDENT ELECTRO-OPTICALLY TUNABLE WAVELENGTH FILTER IN LITHIUM NIOBATE A Dissertation by YANG...

  13. Apparatus And Methods For Launching And Receiving A Broad Wavelength Range Source

    DOE Patents [OSTI]

    Von Drasek, William A. (Oak Forest, IL); Sonnenfroh, David (North Andover, MA); Allen, Mark G. (Boston, MA); Stafford-Evans, Joy (Andover, MA)

    2006-02-28T23:59:59.000Z

    An apparatus and method for simultaneous detection of N gas species through laser radiation attenuation techniques is disclosed. Each of the N species has a spectral absorption band. N laser sources operate at a wavelength ?N in a spectral absorption band separated by the cutoff wavelength for single-mode transmission. Each laser source corresponds to a gas species and transmits radiation through an optical fiber constructed and arranged to provide single-mode transmission with minimal power loss.

  14. Texas Watershed Planning Short Course Final Report 

    E-Print Network [OSTI]

    Wagner, Kevin

    2010-01-01T23:59:59.000Z

    Planning Short Course to water resource professionals throughout Texas. #31;e Planning Team met quarterly to discuss project status, provide input, and coordinate project activities. Planning Team meeting dates, agendas and sign-in sheet can be found.... Considerable progress was made on the short course agenda from input obtained at the third Planning Team meeting on October 1, 2007 at TCEQ in Austin. #30;e Planning Team and representatives from the TCEQ NPS and TMDL Teams, TWRI, AgriLife Research, TSSWCB...

  15. Sensitivity of blackbody effective emissivity to wavelength and temperature: By genetic algorithm

    SciTech Connect (OSTI)

    Ejigu, E. K.; Liedberg, H. G. [National Metrology Institute of South Africa (NMISA), Private Bag X34, Lynnwood Ridge, Pretoria, 0040 (South Africa)] [National Metrology Institute of South Africa (NMISA), Private Bag X34, Lynnwood Ridge, Pretoria, 0040 (South Africa)

    2013-09-11T23:59:59.000Z

    A variable-temperature blackbody (VTBB) is used to calibrate an infrared radiation thermometer (pyrometer). The effective emissivity (?{sub eff}) of a VTBB is dependent on temperature and wavelength other than the geometry of the VTBB. In the calibration process the effective emissivity is often assumed to be constant within the wavelength and temperature range. There are practical situations where the sensitivity of the effective emissivity needs to be known and correction has to be applied. We present a method using a genetic algorithm to investigate the sensitivity of the effective emissivity to wavelength and temperature variation. Two matlab® programs are generated: the first to model the radiance temperature calculation and the second to connect the model to the genetic algorithm optimization toolbox. The effective emissivity parameter is taken as a chromosome and optimized at each wavelength and temperature point. The difference between the contact temperature (reading from a platinum resistance thermometer or liquid in glass thermometer) and radiance temperature (calculated from the ?{sub eff} values) is used as an objective function where merit values are calculated and best fit ?{sub eff} values selected. The best fit ?{sub eff} values obtained as a solution show how sensitive they are to temperature and wavelength parameter variation. Uncertainty components that arise from wavelength and temperature variation are determined based on the sensitivity analysis. Numerical examples are considered for illustration.

  16. Balancing the Energy Budget of Short-Period Giant Planets: Evidence for Reflective Clouds and Optical Absorbers

    E-Print Network [OSTI]

    Schwartz, Joel C

    2015-01-01T23:59:59.000Z

    We consider fifty transiting short-period giant planets for which eclipse depths have been measured at multiple infrared wavelengths. The aggregate dayside emission spectrum of these planets exhibits no molecular features, nor is brightness temperature greater in the near-infrared. We combine brightness temperatures at various infrared wavelengths to estimate the dayside effective temperature of each planet. We find that dayside temperatures are proportional to irradiation temperatures, indicating modest Bond albedo and no internal energy sources, plus weak evidence that dayside temperatures of the hottest planets are disproportionately high. We place joint constraints on Bond albedo, $A_{B}$, and day-to-night transport efficiency, $\\varepsilon$, for six planets by combining thermal eclipse and phase variation measurements (HD 149026b, HD 189733b, HD 209458b, WASP-12b, WASP-18b, and WASP-43b). We confirm that planets with high irradiation temperatures have low heat transport efficiency, and that WASP-43b has ...

  17. Confinement and the Short Type I' Flux Tube

    E-Print Network [OSTI]

    Shyamoli Chaudhuri

    2000-07-18T23:59:59.000Z

    We show that the recent world-sheet analysis of the quantum fluctuations of a short flux tube in type II string theory leads to a simple and precise description of a pair of stuck D0branes in an orientifold compactification of the type I' string theory. The existence of a stable type I' flux tube of sub-string-scale length is a consequence of the confinement of quantized flux associated with the scalar dualized ten-form background field strength *F_{10}, evidence for a -2brane in the BPS spectrum of M theory. Using heterotic-type I duality, we infer the existence of an M2brane of finite width O(\\sqrt{\\alpha'}) in M-theory, the strong coupling resolution of a spacetime singularity in the D=9 twisted and toroidally compactified E_8 x E_8 heterotic string. This phenomenon has a bosonic string analog in the existence of a stable short electric flux tube arising from the confinement of photons due to tachyon field dynamics. The appendix clarifies the appearance of nonperturbative states and enhanced gauge symmetry in toroidal compactifications of the type I' string. We account for all of the known disconnected components of the moduli space of theories with sixteen supercharges, in striking confirmation of heterotic-type I duality.

  18. THE AFTERGLOW AND ENVIRONMENT OF THE SHORT GRB 111117A

    SciTech Connect (OSTI)

    Margutti, R.; Berger, E.; Fong, W.; Zauderer, B. A.; Soderberg, A. M.; Milisavljevic, D.; Sanders, N. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Cenko, S. B. [Department of Astronomy, University of California, Berkeley, CA 94720 (United States); Greiner, J. [Max-Planck-Institut fuer Extraterrestrische Physik, D-85740 Garching (Germany); Cucchiara, A. [Department of Astronomy and Astrophysics, UCO/Lick Observatory, University of California, 1156 High Street, Santa Cruz, CA 95064 (United States); Rossi, A.; Klose, S.; Schmidl, S. [Thueringer Landessternwarte Tautenburg, Sternwarte 5, D-07778 Tautenburg (Germany)

    2012-09-01T23:59:59.000Z

    We present multi-wavelength observations of the afterglow of the short GRB 111117A, and follow-up observations of its host galaxy. From rapid optical and radio observations, we place limits of r {approx}> 25.5 mag at {delta}t Almost-Equal-To 0.55 days and F{sub {nu}}(5.8 GHz) {approx}< 18 {mu}Jy at {delta}t Almost-Equal-To 0.50 days, respectively. However, using a Chandra observation at {delta}t Almost-Equal-To 3.0 days we locate the absolute position of the X-ray afterglow to an accuracy of 0.''22 (1{sigma}), a factor of about six times better than the Swift/XRT position. This allows us to robustly identify the host galaxy and to locate the burst at a projected offset of 1.''25 {+-} 0.''20 from the host centroid. Using optical and near-IR observations of the host galaxy we determine a photometric redshift of z = 1.3{sup +0.3}{sub -0.2}, one of the highest for any short gamma-ray burst (GRB), leading to a projected physical offset for the burst of 10.5 {+-} 1.7 kpc, typical of previous short GRBs. At this redshift, the isotropic {gamma}-ray energy is E{sub {gamma},iso} Almost-Equal-To 3.0 Multiplication-Sign 10{sup 51} erg (rest-frame 23-2300 keV) with a peak energy of E{sub pk} Almost-Equal-To 850-2300 keV (rest-frame). In conjunction with the isotropic X-ray energy, GRB 111117A appears to follow our recently reported E{sub x,iso}-E{sub {gamma},iso}-E{sub pk} universal scaling. Using the X-ray data along with the optical and radio non-detections, we find that for a blastwave kinetic energy of E{sub K,iso} Almost-Equal-To E{sub {gamma},iso} erg, the circumburst density is n{sub 0} Almost-Equal-To 3 Multiplication-Sign 10{sup -4} - 1 cm{sup -3} (for a range of {epsilon}{sub B} = 0.001-0.1). Similarly, from the non-detection of a break in the X-ray light curve at {delta}t {approx}< 3 days, we infer a minimum opening angle for the outflow of {theta}{sub j} {approx}> 3-10 Degree-Sign (depending on the circumburst density). We conclude that Chandra observations of short GRBs are effective at determining precise positions and robust host galaxy associations in the absence of optical and radio detections.

  19. Means for limiting and ameliorating electrode shorting

    DOE Patents [OSTI]

    Van Konynenburg, Richard A. (Livermore, CA); Farmer, Joseph C. (Tracy, CA)

    1999-01-01T23:59:59.000Z

    A fuse and filter arrangement for limiting and ameliorating electrode shorting in capacitive deionization water purification systems utilizing carbon aerogel, for example. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This is important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protect the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conducting particle from migrating through the electrode stack, shorting a series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair and a set of screens of filters in the water flow channels between each set of electrode pairs.

  20. Means for limiting and ameliorating electrode shorting

    SciTech Connect (OSTI)

    Konynenburg, R.A. van; Farmer, J.C.

    1999-11-09T23:59:59.000Z

    A fuse and filter arrangement is described for limiting and ameliorating electrode shorting in capacitive deionization water purification systems utilizing carbon aerogel, for example. This arrangement limits and ameliorates the effects of conducting particles or debonded carbon aerogel in shorting the electrodes of a system such as a capacitive deionization water purification system. This is important because of the small interelectrode spacing and the finite possibility of debonding or fragmentation of carbon aerogel in a large system. The fuse and filter arrangement electrically protect the entire system from shutting down if a single pair of electrodes is shorted and mechanically prevents a conducting particle from migrating through the electrode stack, shorting a series of electrode pairs in sequence. It also limits the amount of energy released in a shorting event. The arrangement consists of a set of circuit breakers or fuses with one fuse or breaker in the power line connected to one electrode of each electrode pair and a set of screens of filters in the water flow channels between each set of electrode pairs.

  1. Electricity storage for short term power system service (Smart...

    Open Energy Info (EERE)

    storage for short term power system service (Smart Grid Project) Jump to: navigation, search Project Name Electricity storage for short term power system service Country Denmark...

  2. Polarization operator approach to pair creation in short laser pulses

    E-Print Network [OSTI]

    Sebastian Meuren; Karen Z. Hatsagortsyan; Christoph H. Keitel; Antonino Di Piazza

    2015-01-28T23:59:59.000Z

    Short-pulse effects are investigated for the nonlinear Breit-Wheeler process, i.e. the production of an electron-positron pair induced by a gamma photon inside an intense plane-wave laser pulse. To obtain the total pair-creation probability we verify (to leading-order) the cutting rule for the polarization operator in the realm of strong-field QED by an explicit calculation. Using a double-integral representation for the leading-order contribution to the polarization operator, compact expressions for the total pair-creation probability inside an arbitrary plane-wave background field are derived. Correspondingly, the photon wave function including leading-order radiative corrections in the laser field is obtained via the Schwinger-Dyson equation in the quasistatic approximation. Moreover, the influence of the carrier-envelope phase and of the laser pulse shape on the total pair-creation probability in a linearly polarized laser pulse is investigated, and the validity of the (local) constant-crossed field approximation analyzed. It is shown that with presently available technology pair-creation probabilities of the order of ten percent could be reached for a single gamma photon.

  3. Orientational ordering of short LC rods in an anisotropic liquid crystalline polymer glass

    E-Print Network [OSTI]

    Cao, Jianshu

    Orientational ordering of short LC rods in an anisotropic liquid crystalline polymer glass Lorin the glass transition is determined by field theory. Microscopic anisotropic interactions can align the LC the glass transition. Host anisotropic glass formers made of mesogens with side chains were studied recently

  4. IEEE SIGNAL PROCESSING LETTERS, VOL. 15, 2008 461 Exploiting Conjugate Symmetry of the Short-Time

    E-Print Network [OSTI]

    -Time Fourier Spectrum for Speech Enhancement Kamil Wójcicki, Mitar Milacic, Anthony Stark, James Lyons, and Kuldip Paliwal, Member, IEEE Abstract--Typical speech enhancement algorithms operate on the short, speech en- hancement. I. INTRODUCTION IN the field of speech enhancement, we are interested

  5. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, J.A.; Greenwald, S.

    1989-05-30T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications is disclosed. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle. 10 figs.

  6. High field gradient particle accelerator

    DOE Patents [OSTI]

    Nation, John A. (Ithaca, NY); Greenwald, Shlomo (Haifa, IL)

    1989-01-01T23:59:59.000Z

    A high electric field gradient electron accelerator utilizing short duration, microwave radiation, and capable of operating at high field gradients for high energy physics applications or at reduced electric field gradients for high average current intermediate energy accelerator applications. Particles are accelerated in a smooth bore, periodic undulating waveguide, wherein the period is so selected that the particles slip an integral number of cycles of the r.f. wave every period of the structure. This phase step of the particles produces substantially continuous acceleration in a traveling wave without transverse magnetic or other guide means for the particle.

  7. Short Gamma-Ray Bursts Are Different

    E-Print Network [OSTI]

    J. P. Norris; J. D. Scargle; J. T. Bonnell

    2001-05-07T23:59:59.000Z

    We analyze BATSE time-tagged event (TTE) data for short gamma-ray bursts (T90 duration burst. Performing the cross-correlation between two energy bands, we measure an average lag ~ 20-40 x shorter than for long bursts, and a lag distribution close to symmetric about zero - unlike long bursts. Using a "Bayesian Block" method to identify significantly distinct pulse peaks, we find an order of magnitude fewer pulses than found in studies of long bursts. The disparity in lag magnitude is discontinuous across the ~ 2-s valley between long and short bursts. Thus, short bursts do not appear to be representable as a continuation of long bursts' temporal characteristics.

  8. Sub-optical wavelength acoustic wave modulation of integrated photonic resonators at microwave frequencies

    E-Print Network [OSTI]

    Semere Ayalew Tadesse; Mo Li

    2014-10-04T23:59:59.000Z

    Light-sound interactions have long been exploited in various acousto-optic devices based on bulk crystalline materials. Conventionally these devices operate in megahertz frequency range where the acoustic wavelength is much longer than the optical wavelength and a long interaction length is required to attain significant coupling. With nanoscale transducers, acoustic waves with sub-optical wavelengths can now be excited to induce strong acousto-optic coupling in nanophotonic devices. Here we demonstrate microwave frequency surface acoustic wave transducers co-integrated with nanophotonic resonators on piezoelectric aluminum nitride substrates. Acousto-optic modulation of the resonance modes at above 10 GHz with the acoustic wavelength significantly below the optical wavelength is achieved. The phase and modal matching conditions in this scheme are investigated for efficient modulation. The new acousto-optic platform can lead to novel optical devices based on nonlinear Brillouin processes and provides a direct, wideband link between optical and microwave photons for microwave photonics and quantum optomechanics.

  9. Time-stretch microscopy based on time-wavelength sequence reconstruction from wideband incoherent source

    SciTech Connect (OSTI)

    Zhang, Chi, E-mail: chizheung@gmail.com; Xu, Yiqing; Wei, Xiaoming; Tsia, Kevin K.; Wong, Kenneth K. Y., E-mail: kywong@eee.hku.hk [Photonic Systems Research Laboratory, Department of Electrical and Electronic Engineering, The University of Hong Kong, Pokfulam Road (Hong Kong)

    2014-07-28T23:59:59.000Z

    Time-stretch microscopy has emerged as an ultrafast optical imaging concept offering the unprecedented combination of the imaging speed and sensitivity. However, dedicated wideband and coherence optical pulse source with high shot-to-shot stability has been mandated for time-wavelength mapping—the enabling process for ultrahigh speed wavelength-encoded image retrieval. From the practical point of view, exploiting methods to relax the stringent requirements (e.g., temporal stability and coherence) for the source of time-stretch microscopy is thus of great value. In this paper, we demonstrated time-stretch microscopy by reconstructing the time-wavelength mapping sequence from a wideband incoherent source. Utilizing the time-lens focusing mechanism mediated by a narrow-band pulse source, this approach allows generation of a wideband incoherent source, with the spectral efficiency enhanced by a factor of 18. As a proof-of-principle demonstration, time-stretch imaging with the scan rate as high as MHz and diffraction-limited resolution is achieved based on the wideband incoherent source. We note that the concept of time-wavelength sequence reconstruction from wideband incoherent source can also be generalized to any high-speed optical real-time measurements, where wavelength is acted as the information carrier.

  10. Formation of nanoparticles by short and ultra-short laser pulses K. Gouriet*a

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    Formation of nanoparticles by short and ultra-short laser pulses K. Gouriet*a , T. E. Itinaa , S. Noëla , J. Hermanna , M. Sentisa , and L. Zhigileib a Laboratory of Lasers, Plasmas and Photonics simulation Monte Carlo (DSMC) computational study of laser ablation plume evolution. The first process

  11. Mechanisms of small clusters production by short and ultra-short laser ablation

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    Mechanisms of small clusters production by short and ultra-short laser ablation Tatiana E. Itina a Lasers, Plasmas et Proce´de´s Photoniques (LP3 UMR 6182 CNRS), Faculte´ des Sciences de Luminy, Case 917 The mechanisms involved into the formation of clusters by pulsed laser ablation are studied both numerically

  12. Catalysts for synthesizing various short chain hydrocarbons

    DOE Patents [OSTI]

    Colmenares, Carlos (Alamo, CA)

    1991-01-01T23:59:59.000Z

    Method and apparatus (10), including novel photocatalysts, are disclosed for the synthesis of various short chain hydrocarbons. Light-transparent SiO.sub.2 aerogels doped with photochemically active uranyl ions (18) are fluidized in a fluidized-bed reactor (12) having a transparent window (16), by hydrogen and CO, C.sub.2 H.sub.4 or C.sub.2 H.sub.6 gas mixtures (20), and exposed to radiation (34) from a light source (32) external to the reactor (12), to produce the short chain hydrocarbons (36).

  13. Gasoline prices up this week (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name:24, 2014long version)short version)short

  14. A two component jet model for the X-ray afterglow flat segment in short GRB 051221A

    E-Print Network [OSTI]

    Zhi-Ping Jin; Ting Yan; Yi-Zhong Fan; Da-Ming Wei

    2007-01-20T23:59:59.000Z

    In the double neutron star merger or neutron star-black hole merger model for short GRBs, the outflow launched might be mildly magnetized and neutron rich. The magnetized neutron-rich outflow will be accelerated by the magnetic and thermal pressure and may form a two component jet finally, as suggested by Vlahakis, Peng & K\\"{o}nigl (2003). We show in this work that such a two component jet model could well reproduce the multi-wavelength afterglow lightcurves, in particular the X-ray flat segment, of short GRB 051221A. In this model, the central engine need not to be active much longer than the prompt $\\gamma-$ray emission.

  15. Demonstrated Wavelength Portability of Raman Reference Data for Explosives and Chemical Detection

    SciTech Connect (OSTI)

    Johnson, Timothy J.; Su, Yin-Fong; Jarman, Kristin H.; Kunkel, Brenda M.; Birnbaum, Jerome C.; Joly, Alan G.; Stephan, Eric G.; Tonkyn, Russell G.; Ewing, Robert G.; Dunham, Glen C.

    2012-04-17T23:59:59.000Z

    As Raman spectroscopy continues to evolve, questions arise as to the portability of Raman data: dispersive versus Fourier transform, wavelength calibration, intensity calibration, and in particular the frequency of the excitation laser. While concerns about fluorescence arise in the visible or ultraviolet, most modern (portable) systems use near-infrared excitation lasers, and many of these are relatively close in wavelength. We have investigated the possibility of porting reference data sets from one NIR wavelength system to another. We have constructed a reference library consisting of 145 spectra, including 20 explosives, as well as sundry other compounds and materials using a 1064 nm spectrometer. These data were used as a reference library to evaluate the same 145 compounds whose experimental spectra were recorded using a second 785 nm spectrometer. In 128 cases of 145 (or 88.3% including 20/20 for the explosives) the compounds were correctly identified with a mean 'hit score' of 954 of 1000. Adding in criteria for when to declare a correct match versus when to declare uncertainty, the approach was able to correctly categorize 134 out of 145 spectra, giving a 92.4% accuracy. For the few that were incorrectly identified, either the matched spectra were spectroscopically similar to the target or the 785 nm signal was degraded due to fluorescence. The results indicate that imported data recorded at a different NIR wavelength can be successfully used as reference libraries, but key issues must be addressed: The reference data must be of equal or higher resolution, the systems require rigorous wavelength calibration, and wavelength-dependent intensity response should be accounted for in the different systems.

  16. Short Communication Application of bare gold nanoparticles

    E-Print Network [OSTI]

    Miksik, Ivan

    Short Communication Application of bare gold nanoparticles in open-tubular CEC separations of polyaromatic hydrocarbons and peptides In this study, bare gold nanoparticles (GNPs) immobilized in the sol capillary wall and improving their resolution. Keywords: CE / Gold nanoparticles / Peptides / Polyaromatic

  17. Short Communication Concurrent correction method for modeling

    E-Print Network [OSTI]

    Kirby, James T.

    Short Communication Concurrent correction method for modeling morphological response to dredging the morphological impact of an offshore dredging pit using a process-based model, the hydrodynamic conditions, often with the initial bathymetry profile before dredging. This lack of equilibrium causes a fast profile adjustment

  18. SHORT CONTRIBUTION J. Choi S. Y. Lee

    E-Print Network [OSTI]

    1990). To date, there have been several reports on the pro- cess analysis and economic evaluation and methods Process analysis and economic evaluation of P(3HB/V) production and recovery were carried outSHORT CONTRIBUTION J. Choi á S. Y. Lee Economic considerations in the production of poly(3

  19. Cosmological consequences of short distance physics

    E-Print Network [OSTI]

    Niemeyer, J C

    2002-01-01T23:59:59.000Z

    Inflation can act as a space-time microscope for Planck or string scale effects, leaving potentially observable traces in the primordial perturbation spectrum. I discuss two frameworks that were used recently to study this phenomenon: nonlinear dispersion and short distance uncertainty.

  20. Cosmological consequences of short distance physics

    E-Print Network [OSTI]

    Jens C. Niemeyer

    2002-01-30T23:59:59.000Z

    Inflation can act as a space-time microscope for Planck or string scale effects, leaving potentially observable traces in the primordial perturbation spectrum. I discuss two frameworks that were used recently to study this phenomenon: nonlinear dispersion and short distance uncertainty.

  1. Video Production For Short Educational Videos

    E-Print Network [OSTI]

    Video Production Handbook For Short Educational Videos Jennifer Cook Small Acreage Management page 6 Introduction page 3 Prepare for Video Shoot page 8 Video Shoot page 9 Editing Page 11 Draft Review page 12 Final Video page 13 Table of Contents Video Production Process #12;3 Equipment

  2. Short Specialist Review Gene structure prediction

    E-Print Network [OSTI]

    Brendel, Volker

    Short Specialist Review Gene structure prediction in plant genomes Volker Brendel Iowa State) within most genes makes the problem of computational gene structure prediction distinct from (and harder prediction in vertebrates. The second reason is pragmatic. Expressed Sequence Tag (EST) sequencing and whole

  3. SHORT COMMUNICATION Chiral Enrichment of Serine

    E-Print Network [OSTI]

    Clemmer, David E.

    SHORT COMMUNICATION Chiral Enrichment of Serine via Formation, Dissociation, and Soft University, Bloomington, Indiana, USA Chiral enrichment of serine is achieved in experiments that involve of chirally-enriched octameric cluster ions and their dissociation, viz. Ser1 3 Ser8 3 Ser1, allows serine

  4. Varying speed of light cosmology from a stringy short distance cutoff

    E-Print Network [OSTI]

    J. C. Niemeyer

    2001-11-26T23:59:59.000Z

    It is shown that varying speed of light cosmology follows from a string-inspired minimal length uncertainty relation. Due to the reduction of the available phase space volume per quantum mode at short wavelengths, the equation of state of ultrarelativistic particles stiffens at very high densities. This causes a stronger than usual deceleration of the scale factor which competes with a higher than usual propagation speed of the particles. Various measures for the effective propagation speed are analyzed: the group and phase velocity in the high energy tail, the thermal average of the group and phase velocity, and the speed of sound. Of these three groups, only the first provides a possible solution to the cosmological horizon problem.

  5. Varying speed of light cosmology from a stringy short distance cutoff

    E-Print Network [OSTI]

    Niemeyer, J C

    2002-01-01T23:59:59.000Z

    It is shown that varying speed of light cosmology follows from a string-inspired minimal length uncertainty relation. Due to the reduction of the available phase space volume per quantum mode at short wavelengths, the equation of state of ultrarelativistic particles stiffens at very high densities. This causes a stronger than usual deceleration of the scale factor which competes with a higher than usual propagation speed of the particles. Various measures for the effective propagation speed are analyzed: the group and phase velocity in the high energy tail, the thermal average of the group and phase velocity, and the speed of sound. Of these three groups, only the first provides a possible solution to the cosmological horizon problem.

  6. Advanced Mitigating Measures for the Cell Internal Short Risk (Presentation)

    SciTech Connect (OSTI)

    Darcy, E.; Smith, K.

    2010-04-01T23:59:59.000Z

    This presentation describes mitigation measures for internal short circuits in lithium-ion battery cells.

  7. Evaluation of wavelength shifters for spectral separation of barium fluoride emissions

    SciTech Connect (OSTI)

    DeVol, T.A. [Michigan Univ., Ann Arbor, MI (United States)

    1993-10-01T23:59:59.000Z

    BaF{sub 2} has the advantage over other scintillators, when comparing radiation hardness, scintillation decay time, and fast scintillation yield. Since the fast BaF{sub 2} emissions have peak wavelengths of 220, 195, and 170 nm, a wavelength shifter (WLS) is needed. Organic fluors were evaluated as WLS components. Results indicate that spectral separation using WLS is possible, but not to the extent desired; other techniques must be used also. Alternative scintillators, such as CeF{sub 3}, should be investigated.

  8. Reliability of temperature determination from curve-fitting in multi-wavelength pyrometery

    SciTech Connect (OSTI)

    Ni, P.A.; More, R.M.; Bieniosek, F.M.

    2013-08-04T23:59:59.000Z

    Abstract This paper examines the reliability of a widely used method for temperature determination by multi-wavelength pyrometry. In recent WDM experiments with ion-beam heated metal foils, we found that the statistical quality of the fit to the measured data is not necessarily a measure of the accuracy of the inferred temperature. We found a specific example where a second-best fit leads to a more realistic temperature value. The physics issue is the wavelength-dependent emissivity of the hot surface. We discuss improvements of the multi-frequency pyrometry technique, which will give a more reliable determination of the temperature from emission data.

  9. High channel density wavelength division multiplexer with defined diffracting means positioning

    DOE Patents [OSTI]

    Jannson, Tomasz P. (Redondo Beach, CA); Jannson, Joanna L. (Redondo Beach, CA); Yeung, Peter C. (Redondo Beach, CA)

    1990-01-01T23:59:59.000Z

    A wavelength division multiplexer/demultiplexer having optical path lengths between a fiber array and a Fourier transform lens, and between a dispersion grating and the lens equal to the focal length of the lens. The optical path lengths reduce losses due to angular acceptance mismatch in the multiplexer. Close orientation of the fiber array about the optical axis and the use of a holographic dispersion grating reduces other losses in the system. Multi-exposure holographic dispersion gratings enable the multiplexer/demultiplexer for extremely broad-band simultaneous transmission and reflection operation. Individual Bragg plane sets recorded in the grating are dedicated to and operate efficiently on discrete wavelength ranges.

  10. Dark Field Microscopy for Analytical Laboratory Courses

    SciTech Connect (OSTI)

    Augspurger, Ashley E.; Stender, Anthony S.; Marchuk, Kyle; Greenbowe, Thomas J.; Fang, Ning

    2014-06-10T23:59:59.000Z

    An innovative and inexpensive optical microscopy experiment for a quantitative analysis or an instrumental analysis chemistry course is described. The students have hands-on experience with a dark field microscope and investigate the wavelength dependence of localized surface plasmon resonance in gold and silver nanoparticles. Students also observe and measure individual crystal growth during a replacement reaction between copper and silver nitrate. The experiment allows for quantitative, qualitative, and image data analyses for undergraduate students.

  11. HETEROGENEITY IN SHORT GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Norris, Jay P. [Physics and Astronomy Department, University of Denver, Denver, CO 80208 (United States); Gehrels, Neil [Astroparticle Physics Laboratory, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Scargle, Jeffrey D. [Space Science and Astrobiology Division, NASA/Ames Research Center, Moffett Field, CA 94035-1000 (United States)

    2011-07-01T23:59:59.000Z

    We analyze the Swift/BAT sample of short gamma-ray bursts, using an objective Bayesian Block procedure to extract temporal descriptors of the bursts' initial pulse complexes (IPCs). The sample is comprised of 12 and 41 bursts with and without extended emission (EE) components, respectively. IPCs of non-EE bursts are dominated by single pulse structures, while EE bursts tend to have two or more pulse structures. The medians of characteristic timescales-durations, pulse structure widths, and peak intervals-for EE bursts are factors of {approx}2-3 longer than for non-EE bursts. A trend previously reported by Hakkila and colleagues unifying long and short bursts-the anti-correlation of pulse intensity and width-continues in the two short burst groups, with non-EE bursts extending to more intense, narrower pulses. In addition, we find that preceding and succeeding pulse intensities are anti-correlated with pulse interval. We also examine the short burst X-ray afterglows as observed by the Swift/X-Ray Telescope (XRT). The median flux of the initial XRT detections for EE bursts ({approx}6x10{sup -10} erg cm{sup -2} s{sup -1}) is {approx}>20x brighter than for non-EE bursts, and the median X-ray afterglow duration for EE bursts ({approx}60,000 s) is {approx}30x longer than for non-EE bursts. The tendency for EE bursts toward longer prompt-emission timescales and higher initial X-ray afterglow fluxes implies larger energy injections powering the afterglows. The longer-lasting X-ray afterglows of EE bursts may suggest that a significant fraction explode into denser environments than non-EE bursts, or that the sometimes-dominant EE component efficiently powers the afterglow. Combined, these results favor different progenitors for EE and non-EE short bursts.

  12. Time variations of Mars' gravitational field and seasonal changes in the masses of the polar ice caps

    E-Print Network [OSTI]

    Smith, David E.

    Tracking of the Mars Global Surveyor spacecraft has been used to measure changes in the long-wavelength gravity field of Mars and to estimate the seasonal mass of carbon dioxide that is deposited in the polar regions each ...

  13. Short-term exploitative competition can explain human foraging patterns

    E-Print Network [OSTI]

    Saavedra, Serguei; Switanek, Nicholas; Uzzi, Brian

    2012-01-01T23:59:59.000Z

    Theory purports that animal foraging choices evolve to maximize returns, such as net energy intake. Empirical research in both human and nonhuman animals reveals that many times foraging choices are context dependent and affected by the foraging choices of others. Yet, broad empirical facts on the link between optimal foraging patterns, competition and context-dependent information are only now emerging due to the complication of gathering field data or constructing experiments. Here, we analyze foraging choices by a cohort of professional day traders who face the trade-off of trading the same stock multiple times in a row---patch exploitation---or switching to a different stock---patch exploration---with potentially higher returns. Our findings indicate that traders' foraging patterns are characterized by short-term comparative returns that decrease in proportion to patch exploitation and exploration, a novel measure that captures the difference between a trader's resource intake and the competitors' expecte...

  14. Short-range atmospheric dispersion of carbon dioxide

    SciTech Connect (OSTI)

    Cortis, A.; Oldenburg, C.M.

    2009-11-01T23:59:59.000Z

    We present a numerical study aimed at quantifying the effects of concentration-dependent density on the spread of a seeping plume of CO{sub 2} into the atmosphere such as could arise from a leaking geologic carbon sequestration site. Results of numerical models can be used to supplement field monitoring estimates of CO{sub 2} seepage flux by modelling transport and dispersion between the source emission and concentration-measurement points. We focus on modelling CO{sub 2} seepage dispersion over relatively short distances where density effects are likely to be important. We model dense gas dispersion using the steady-state Reynolds-averaged Navier-Stokes equations with density dependence in the gravity term. Results for a two-dimensional system show that a density dependence emerges at higher fluxes than prior estimates. A universal scaling relation is derived that allows estimation of the flux from concentrations measured downwind and vice versa.

  15. An evaluation of reduced amounts of advance traffic control for short duration and stop-and-go maintenance operations

    E-Print Network [OSTI]

    Balke, Kevin Neil

    1987-01-01T23:59:59.000Z

    of driver information as the traffic control setup for a short-term, minor maintenance operation. Four field studies were performed on a total of six candidate signing treatments with the cone taper. An additional two field studies that studied a total... of five of the candidate signing treatments without the cone taper were performed. Both lane distribution and erratic maneuvers were used to measure the performance of the candidate treatments. The results of these field studies indicated...

  16. On the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE

    E-Print Network [OSTI]

    Sobel, Adam

    of tropical cyclones; the theory then predicts the zonal separation distance of such tropical cyclone pairsOn the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE Department cyclone (TC). In some cases, such disturbances undergo tropical cyclogenesis, resulting in a pair

  17. Wavelength-space permutation switch with coherent PDM QPSK transmission for supercomputer optical interconnects

    E-Print Network [OSTI]

    Vlachos, Kyriakos G.

    Several low-cost, low-latency, high throughput optical interconnect architectures have been proposed interconnects F. Karinou (1), I. Roudas (1), K. Vlachos (1), C. S. Petrou (1), . Vgenis (1), and B. R. Hemenway optical interconnect employing wavelength-space optical packet switching, polarization division

  18. Electro-optic coefficients of lithium tantalate at near-infrared wavelengths

    E-Print Network [OSTI]

    Gopalan, Venkatraman

    Electro-optic coefficients of lithium tantalate at near-infrared wavelengths Joanna L. Casson April 27, 2004 The unclamped linear electro-optic coefficients r13 and r33 for lithium tantalate. In the unclamped mode the effects of mechanical changes caused by piezoelectric and elasto-optic effects

  19. Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy

    E-Print Network [OSTI]

    Wang, Lihong

    Three-dimensional imaging of skin melanoma in vivo by dual-wavelength photoacoustic microscopy Jung to noninvasively obtain three-dimensional 3-D images of subcutaneous melanomas and their surrounding vasculature in nude mice in vivo. The absorption coefficients of blood and melanin- pigmented melanomas vary greatly

  20. Wavelength tunable polarization mode converter utilizing static strain effects in lithium niobate

    E-Print Network [OSTI]

    Kwon, Ojin

    1999-01-01T23:59:59.000Z

    Electro-optically tunable polarization mode converters have been produced in LiNbO? substrate using all static strain optic effects. Maximum conversion efficiency of 98.3% was achieved at 66414m wavelength in TE to TM conversion, and 95...

  1. Wavelength tunable polarization mode converter utilizing static strain effects in lithium niobate 

    E-Print Network [OSTI]

    Kwon, Ojin

    1999-01-01T23:59:59.000Z

    Electro-optically tunable polarization mode converters have been produced in LiNbO? substrate using all static strain optic effects. Maximum conversion efficiency of 98.3% was achieved at 66414m wavelength in TE to TM conversion, and 95...

  2. Collision-induced pulse timing jitter in a wavelength-division-multiplexing

    E-Print Network [OSTI]

    Yang, Jianke

    Collision-induced pulse timing jitter in a wavelength-division-multiplexing system with strong of the most serious problems in the use of WDM is the cross talk (equivalent to a random timing jitter) in explanation for the advantages offered by DM, such as suppression of the soliton's jitter and interaction

  3. Wavelength and power monitoring of DWDM systems using scanning FP filter calibrated with a FP laser

    E-Print Network [OSTI]

    Wai, Ping-kong Alexander

    Wavelength and power monitoring of DWDM systems using scanning F­P filter calibrated with a F, Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR Polytechnic University, Hung Hom, Kowloon, Hong Kong SAR , People's Republic of China c Division

  4. Light Trapping Textures Designed by Electromagnetic Optimization for Sub-Wavelength Thick Solar Cells

    E-Print Network [OSTI]

    California at Irvine, University of

    the surface of the solar cell, where n is the material refractive index. This ray-optics absorption enhancement limit only holds when the thickness of the solar cell is much greater than the optical wavelength limit of 4n2 50. Introduction Texturing of solar cell surfaces allows for absorption enhancement, owing

  5. GaN/AlN Quantum Wells and Quantum Dots for Unipolar Devices at Telecommunication Wavelengths

    SciTech Connect (OSTI)

    Julien, Francois H.; Tchernycheva, Maria; Doyennette, Laetitia; Nevou, Laurent; Lupu, Anatole; Warde, Elias [Institut d'Electronique Fondamentale, Universite Paris Sud, UMR 8622 CNRS, 91405 Orsay (France); Guillot, Fabien; Monroy, Eva; Bellet-Amalric, Edith [Equipe mixte CEACNRS-UJF, DRFMC/SP2M/PSC, CEA Grenoble, 17 rue des Martyrs, 38054 Grenoble (France); Vardi, Alon; Bahir, Gad [Departement of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 3200 (Israel)

    2007-04-10T23:59:59.000Z

    We report on the latest achievements in terms of growth and optical investigation of ultrathin GaN/AlN isolated and coupled quantum wells grown by plasma-assisted molecular-beam epitaxy. We also present the observation of intraband absorption in self-organized GaN quantum dots and on the application to infrared photodetection at telecommunication wavelengths.

  6. Sub-wavelength nanofluidics in photonic crystal Min Huang,1,2

    E-Print Network [OSTI]

    Sub-wavelength nanofluidics in photonic crystal sensors Min Huang,1,2 Ahmet Ali Yanik,1,2 , Tsung: We introduce a novel sensor scheme combining nano-photonics and nano-fluidics on a single platform and mechanical approaches to biomolecular detection at the nanoscale." Microfluid. Nanofluid. 4(1­2), 33­52 (2007

  7. Influence of nanoparticle height on plasmonic resonance wavelength and electromagnetic field enhancement in two-dimensional arrays

    E-Print Network [OSTI]

    Paiella, Roberto

    -enhanced spectroscopy, and efficiency enhancement in solid-state light emitters and solar cells.1,2 The tunability and Computer Engineering and Photonics Center, Boston University, 8 St. Mary's Street, Boston, Massachusetts such as light-emission efficiency enhancement. © 2009 American Institute of Physics. doi:10.1063/1.3255979 I

  8. Instrument performance study on the short and long pulse options of the second Spallation Neutron Source target station

    SciTech Connect (OSTI)

    Zhao, J. K.; Herwig, Kenneth W.; Robertson, J. L.; Gallmeier, Franz X.; Riemer, Bernard W. [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)] [Instrument and Source Division, Spallation Neutron Source, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2013-10-15T23:59:59.000Z

    The Spallation Neutron Source (SNS) facility at the Oak Ridge National Laboratory is designed with an upgrade option for a future low repetition rate, long wavelength second target station. This second target station is intended to complement the scientific capabilities of the 1.4 MW, 60 Hz high power first target station. Two upgrade possibilities have been considered, the short and the long pulse options. In the short pulse mode, proton extraction occurs after the pulse compression in the accumulator ring. The proton pulse structure is thus the same as that for the first target station with a pulse width of ?0.7 ?s. In the long pulse mode, protons are extracted as they are produced by the linac, with no compression in the accumulator ring. The time width of the uncompressed proton pulse is ?1 ms. This difference in proton pulse structure means that neutron pulses will also be different. Neutron scattering instruments thus have to be designed and optimized very differently for these two source options which will directly impact the overall scientific capabilities of the SNS facility. In order to assess the merits of the short and long pulse target stations, we investigated a representative suit of neutron scattering instruments and evaluated their performance under each option. Our results indicate that the short pulse option will offer significantly better performance for the instruments and is the preferred choice for the SNS facility.

  9. Short Time Cycles of Purely Quantum Refrigerators

    E-Print Network [OSTI]

    Tova Feldmann; Ronnie Kosloff

    2012-04-18T23:59:59.000Z

    Four stroke Otto refrigerator cycles with no classical analogue are studied. Extremely short cycle times with respect to the internal time scale of the working medium characterize these refrigerators. Therefore these cycles are termed sudden. The sudden cycles are characterized by the stable limit cycle which is the invariant of the global cycle propagator. During their operation the state of the working medium possesses significant coherence which is not erased in the equilibration segments due to the very short time allocated. This characteristic is reflected in a difference between the energy entropy and the Von Neumann entropy of the working medium. A classification scheme for sudden refrigerators is developed allowing simple approximations for the cooling power and coefficient of performance.

  10. Short pulse free electron laser amplifier

    DOE Patents [OSTI]

    Schlitt, Leland G. (Livermore, CA); Szoke, Abraham (Fremont, CA)

    1985-01-01T23:59:59.000Z

    Method and apparatus for amplification of a laser pulse in a free electron laser amplifier where the laser pulse duration may be a small fraction of the electron beam pulse duration used for amplification. An electron beam pulse is passed through a first wiggler magnet and a short laser pulse to be amplified is passed through the same wiggler so that only the energy of the last fraction, f, (f<1) of the electron beam pulse is consumed in amplifying the laser pulse. After suitable delay of the electron beam, the process is repeated in a second wiggler magnet, a third, . . . , where substantially the same fraction f of the remainder of the electron beam pulse is consumed in amplification of the given short laser pulse in each wiggler magnet region until the useful electron beam energy is substantially completely consumed by amplification of the laser pulse.

  11. Short-Range Nucleon-Nucleon Correlations

    SciTech Connect (OSTI)

    Douglas Higinbotham

    2011-10-01T23:59:59.000Z

    Valence-shell nucleon knock-out experiments, such as 12C(e,e'p)11B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between the nucleons in the nucleus in the calculations. Motivated by these results, many electron scattering experiments have tried to directly observe these correlations in order to gain new insight into the short-range part of the nucleon-nucleon potential. Unfortunately, many competing mechanisms can cause the same observable final-state as an initial-state correlation, making truly isolating the signal extremely challenging. This paper reviews the recent experimental evidence for short-range correlations, as well as explores the possibility that such correlations are responsible for the EMC effect in the 0.3 < xB < 0.7 deep inelastic scattering ratios.

  12. Short-Range Nucleon-Nucleon Correlations

    SciTech Connect (OSTI)

    Higinbotham, Douglas W. [Thomas Jefferson National Accelerator Facility, Newport News, VA 23601 (United States)

    2011-10-24T23:59:59.000Z

    Valence-shell nucleon knock-out experiments, such as {sup 12}C(e,e'p){sup 11}B, measure less strength then is predicted by independent particle shell model calculations. The theoretical solution to this problem is to include the correlations between the nucleons in the nucleus in the calculations. Motivated by these results, many electron scattering experiments have tried to isolate the signal from these correlations in order to gain new insight into the short-range part of the nucleon-nucleon potential. Unfortunately, many competing mechanisms can cause the same observable final-state as an initial-state correlation, making truly isolating the signal extremely challenging. This paper reviews the recent experimental evidence for short-range correlations, as well as explores the possibility that such correlations are responsible for the EMC effect in the 0.3

  13. Short distance physics with heavy quark potentials

    E-Print Network [OSTI]

    Zantow, F; Karsch, Frithjof; Petreczky, P

    2002-01-01T23:59:59.000Z

    We present lattice studies of heavy quark potentials in the quenched approximation of QCD at finite temperatures. Both, the color singlet and color averaged potentials are calculated. While the potentials are well known at large distances, we give a detailed analysis of their short distance behavior (from 0.015 fm to 1 fm) near the critical temperature. At these distances we expect that the T-dependent potentials go over into the zero temperature potential. Indeed, we find evidences that the temperature influence gets suppressed and the potentials starts to become a unique function of the underlying distance scale. We use this feature to normalize the heavy quark potentials at short distances and extract the free energy of the quark system in a gluonic heat bath.

  14. Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes

    E-Print Network [OSTI]

    Wetzel, Christian M.

    Wavelength-resolved low-frequency noise of GaInN/GaN green light emitting diodes S. L. Rumyantseva well light emitting diodes. The light intensity noise was measured as a function of wavelength within the light emitting diode spectral emission line. The spectral noise density is found to increase

  15. Wavelength-Invariant Resist Composed of Bimetallic Layers Y. Tu, M. Karimi, N. Morawej, W. N. Lennard1

    E-Print Network [OSTI]

    Chapman, Glenn H.

    and optical characteristics change after laser exposures that produce a rapid thermal anneal in selected areas but there is evidence of melting and recrystallization. Transparency is much lower than after laser annealing. RBS wavelength invariance for wavelengths from Near IR to UV. The laser-induced patterns are developed by an etch

  16. Wavelength dependence of the threshold in an InGaP-InAlGaP vertical cavity surface emitting laser

    SciTech Connect (OSTI)

    Chow, W.W.; Schneider, R.P. Jr.; Lott, J.A.; Choquette, K.D. (Sandia National Laboratories, Albuquerque, New Mexico 87185-0350 (United States))

    1994-07-11T23:59:59.000Z

    The wavelength dependence of the threshold in an InGaP-InAlGaP vertical cavity surface emitting laser is investigated using a microscopic theory of the semiconductor gain medium. Good agreement is found between experiment and theory for the minimum threshold lasing wavelength for a range of laser structures.

  17. 1784 JOURNAL OF LIGHTWAVE TECHNOLOGY, VOL. 20, NO. 9, MAY 1, 2014 A Dual-Wavelength Fiber Ring Laser Incorporating

    E-Print Network [OSTI]

    Yao, Jianping

    at an ultra-high speed. Index Terms--Dual-wavelength laser, fiber laser, fiber optic sen- sor, laser stability Laser Incorporating an Injection-Coupled Optoelectronic Oscillator and Its Application to Transverse--A novel configuration for a dual-wavelength fiber ring laser with improved lasing stability realized

  18. Breit-Wheeler Process in Intense Short Laser Pulses

    E-Print Network [OSTI]

    K. Krajewska; J. Z. Kaminski

    2012-09-11T23:59:59.000Z

    Energy-angular distributions of electron-positron pair creation in collisions of a laser beam and a nonlaser photon are calculated using the $S$-matrix formalism. The laser field is modeled as a finite pulse, similar to the formulation introduced in our recent paper in the context of Compton scattering [Phys. Rev. A {\\bf 85}, 062102 (2012)]. The nonperturbative regime of pair creation is considered here. The energy spectra of created particles are compared with the corresponding spectra obtained using the modulated plane wave approximation for the driving laser field. A very good agreement in these two cases is observed, provided that the laser pulse is sufficiently long. For short pulse durations, this agreement breaks down. The sensitivity of pair production to the polarization of a driving pulse is also investigated. We show that in the nonperturbative regime, the pair creation yields depend on the polarization of the pulse, reaching their maximal values for the linear polarization. Therefore, we focus on this case. Specifically, we analyze the dependence of pair creation on the relative configuration of linear polarizations of the laser pulse and the nonlaser photon. Lastly, we investigate the carrier-envelope phase effect on angular distributions of created particles, suggesting the possibility of phase control in relation to the pair creation processes.

  19. Can short sellers predict accounting restatements and foresee their severity

    E-Print Network [OSTI]

    Efendi, Jap

    2005-11-01T23:59:59.000Z

    insiders. For example, Solomon Smith Barney?s Jack Grubman publicly attacked a short seller who criticized their banking client by stating that short sellers lack an understanding of the communication industry (Gasparino 2002). McGough (1991) describes...

  20. Naked Short Selling: Is it Information-Based Trading?

    E-Print Network [OSTI]

    Liu, Hu

    2012-10-19T23:59:59.000Z

    Naked short selling occurs when a short seller fails to deliver shares on the settlement day. The business press and many corporate managers characterize it as abusive price manipulation, alleging that selling nonexistent shares causes a price...

  1. Hopper compilers and DDT short outage next Wed, May 16

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

    compilers and DDT short outage next Wed, May 16 Hopper compilers and DDT short outage next Wed, May 16 May 10, 2012 (0 Comments) Due to a scheduled maintenance for the License...

  2. Short rise time intense electron beam generator

    DOE Patents [OSTI]

    Olson, Craig L. (Albuquerque, NM)

    1987-01-01T23:59:59.000Z

    A generator for producing an intense relativistic electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.

  3. Short rise time intense electron beam generator

    DOE Patents [OSTI]

    Olson, C.L.

    1984-03-16T23:59:59.000Z

    A generator for producing an intense relativisitc electron beam having a subnanosecond current rise time includes a conventional generator of intense relativistic electrons feeding into a short electrically conductive drift tube including a cavity containing a working gas at a low enough pressure to prevent the input beam from significantly ionizing the working gas. Ionizing means such as a laser simultaneously ionize the entire volume of working gas in the cavity to generate an output beam having a rise time less than one nanosecond.

  4. Neutron scattering and extra short range interactions

    E-Print Network [OSTI]

    V. V. Nesvizhevsky; G. Pignol; K. V. Protasov

    2007-11-14T23:59:59.000Z

    The available data on neutron scattering were analyzed to constrain a hypothetical new short-range interaction. We show that these constraints are several orders of magnitude better than those usually cited in the range between 1 pm and 5 nm. This distance range occupies an intermediate space between collider searches for strongly coupled heavy bosons and searches for new weak macroscopic forces. We emphasise the reliability of the neutron constraints in so far as they provide several independent strategies. We have identified the most promising way to improve them.

  5. Ion Acceleration by Short Chirped Laser Pulses

    E-Print Network [OSTI]

    Li, Jian-Xing; Keitel, Christoph H; Harman, Zoltán

    2015-01-01T23:59:59.000Z

    Direct laser acceleration of ions by short frequency-chirped laser pulses is investigated theoretically. We demonstrate that intense beams of ions with a kinetic energy broadening of about 1 % can be generated. The chirping of the laser pulse allows the particles to gain kinetic energies of hundreds of MeVs, which is required for hadron cancer therapy, from pulses of energies of the order of 100 J. It is shown that few-cycle chirped pulses can accelerate ions more efficiently than long ones, i.e. higher ion kinetic energies are reached with the same amount of total electromagnetic pulse energy.

  6. Short range correlations and the EMC effect

    SciTech Connect (OSTI)

    E. Piasetzky, L.B. Weinstein, D.W. Higinbotham, J. Gomez, O. Hen, R. Shneor

    2011-04-01T23:59:59.000Z

    The magnitude of the EMC effect measured in electron deep inelastic scattering (DIS) is linearly related to the Short Range Correlation (SRC) scaling factor obtained from electron inclusive scattering. We speculate that the observed correlation is due to the fact that both the EMC effect and SRC are dominated by high momentum nucleons in the nucleus. The observed phenomenological relationship can be used to extract the ratio of the deuteron to the free pn-pair cross sections, the DIS cross section for a free neutron, View the MathML source, the ratio of the free neutron to free proton structure functions, and the u/d ratio in a free proton.

  7. Gasoline price shows small increase (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name: Email:UraniumNatural Gas SurveyshowsShort

  8. Gasoline prices continue to decrease (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name: Email:UraniumNatural Gaslong(long19,short

  9. Gasoline prices continue to fall (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name: Email:UraniumNaturallonglong version)short

  10. Gasoline prices show sharp increase (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name:24, 2014long version) Theshort10,short

  11. Gasoline prices up this week (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name:24, 2014long version)short version) The

  12. Gasoline prices up this week (short version)

    U.S. Energy Information Administration (EIA) Indexed Site

    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: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov YouKizildere IRaghuraji Agro IndustriesTownDells, Wisconsin:DeploymentSite Name:24, 2014long version)short version)

  13. Short-Term Energy Outlook- May 2003

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our Instagram Secretary Moniz9 SeptemberSettingUncertainties in the3 1 Short-Term

  14. Short-term energy outlook quarterly projections. Third quarter 1997

    SciTech Connect (OSTI)

    NONE

    1997-07-01T23:59:59.000Z

    This document presents the 1997 third quarter short term energy projections. Information is presented for fossil fuels and renewable energy.

  15. Search for Short Lived Particles in High Multiplicity Environment

    E-Print Network [OSTI]

    Marek Gazdzicki; Waldemar Retyk; Jan Pluta

    1999-04-14T23:59:59.000Z

    A method of statistical selection of short lived particles in high multiplicity nucleus-nucleus collisions is discussed.

  16. 4.0 SHORT FORM LOGO 4.01 OVERVIEW

    E-Print Network [OSTI]

    Lotze, Heike K.

    4.0 SHORT FORM LOGO 4.01 OVERVIEW 4.02 CLEAR SPACE AND MINIMUM SIZE 4.03 AS A WATERMARK 4.04 RETAIL PRODUCTS 4.05 APPLYING THE SHORT FORM LOGO PROPERLY 4.06 LINK TO DALHOUSIE AUTHORIZED SHORT FORM LOGO As part of the 2014 logo refresh, we introduced a short form logo for informal uses such as social media

  17. High-performance parallel processors based on star-coupled wavelength division multiplexing optical interconnects

    DOE Patents [OSTI]

    Deri, Robert J. (Pleasanton, CA); DeGroot, Anthony J. (Castro Valley, CA); Haigh, Ronald E. (Arvada, CO)

    2002-01-01T23:59:59.000Z

    As the performance of individual elements within parallel processing systems increases, increased communication capability between distributed processor and memory elements is required. There is great interest in using fiber optics to improve interconnect communication beyond that attainable using electronic technology. Several groups have considered WDM, star-coupled optical interconnects. The invention uses a fiber optic transceiver to provide low latency, high bandwidth channels for such interconnects using a robust multimode fiber technology. Instruction-level simulation is used to quantify the bandwidth, latency, and concurrency required for such interconnects to scale to 256 nodes, each operating at 1 GFLOPS performance. Performance scales have been shown to .apprxeq.100 GFLOPS for scientific application kernels using a small number of wavelengths (8 to 32), only one wavelength received per node, and achievable optoelectronic bandwidth and latency.

  18. Absorptivity modulation on wavy molten steel surfaces: The influence of laser wavelength and angle of incidence

    SciTech Connect (OSTI)

    Kaplan, A. F. H. [Department of Engineering Sciences and Mathematics, Lulea University of Technology, S-971 87 Lulea (Sweden)

    2012-10-08T23:59:59.000Z

    The modulation of the angle-dependent Fresnel absorptivity across wavy molten steel surfaces during laser materials processing, like drilling, cutting, or welding, has been calculated. The absorptivity is strongly altered by the grazing angle of incidence of the laser beam on the processing front. Owing to its specific Brewster-peak characteristics, the 10.64 {mu}m wavelength CO{sub 2}-laser shows an opposite trend with respect to roughness and angle-of-incidence compared to lasers in the wavelength range of 532-1070 nm. Plateaus or rings of Brewster-peak absorptivity can lead to hot spots on a wavy surface, often in close proximity to cold spots caused by shadow domains.

  19. High channel density wavelength division multiplexer with defined diffracting means positioning

    DOE Patents [OSTI]

    Jannson, T.P.; Jannson, J.L.; Yeung, P.C.

    1990-05-15T23:59:59.000Z

    A wavelength division multiplexer/demultiplexer is disclosed having optical path lengths between a fiber array and a Fourier transform lens, and between a dispersion grating and the lens equal to the focal length of the lens. The optical path lengths reduce losses due to angular acceptance mismatch in the multiplexer. Close orientation of the fiber array about the optical axis and the use of a holographic dispersion grating reduces other losses in the system. Multi-exposure holographic dispersion gratings enable the multiplexer/demultiplexer for extremely broad-band simultaneous transmission and reflection operation. Individual Bragg plane sets recorded in the grating are dedicated to and operate efficiently on discrete wavelength ranges. 11 figs.

  20. Wavelength measurement of n = 3 - n' = 3 transitions in highly charged tungsten ions

    SciTech Connect (OSTI)

    Clementson, J; Beiersdorfer, P

    2010-03-10T23:59:59.000Z

    3s{sub 1/2} - 3p{sub 3/2} and 3p{sub 1/2} - 3d{sub 3/2} transitions have been studied in potassium-like W{sup 55+} through neon-like W{sup 64}+ ions at the electron-beam ion trap facility in Livermore. The wavelengths of the lines have been measured in high resolution relative to well known reference lines from oxygen and nitrogen ions. Using the high-energy SuperEBIT electron-beam ion trap and an R = 44.3 m grazing-incidence soft x-ray spectrometer, the lines were observed with a cryogenic charge-coupled device camera. The wavelength data for the sodium-like and magnesium-like tungsten lines are compared with theoretical predictions for ions along the isoelectronic sequences.

  1. Ground-state cooling of a trapped ion using long-wavelength radiation

    E-Print Network [OSTI]

    S. Weidt; J. Randall; S. C. Webster; E. D. Standing; A. Rodriguez; A. E. Webb; B. Lekitsch; W. K. Hensinger

    2015-01-07T23:59:59.000Z

    We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

  2. Ground-state cooling of a trapped ion using long-wavelength radiation

    E-Print Network [OSTI]

    Weidt, S; Webster, S C; Standing, E D; Rodriguez, A; Webb, A E; Lekitsch, B; Hensinger, W K

    2015-01-01T23:59:59.000Z

    We demonstrate ground-state cooling of a trapped ion using long-wavelength radiation. This is a powerful tool for the implementation of quantum operations, where long-wavelength radiation instead of lasers is used for motional quantum state engineering. We measure a mean phonon number of $\\overline{n} = 0.13(4)$ after sideband cooling, corresponding to a ground-state occupation probability of 88(7)\\%. After preparing in the vibrational Fock state $\\left|n=0\\right\\rangle$, we implement sideband Rabi oscillations which last for more than 10 ms, demonstrating the long coherence time of our system. We also use the ability to ground-state cool to accurately measure the motional heating rate and report a reduction by almost two orders of magnitude compared to our previously measured result, which we attribute to carefully eliminating sources of electrical noise in the system.

  3. Method for measuring thermal properties using a long-wavelength infrared thermal image

    DOE Patents [OSTI]

    Walker, Charles L. (Albuquerque, NM); Costin, Laurence S. (Albuquerque, NM); Smith, Jody L. (Albuquerque, NM); Moya, Mary M. (Albuquerque, NM); Mercier, Jeffrey A. (Albuquerque, NM)

    2007-01-30T23:59:59.000Z

    A method for estimating the thermal properties of surface materials using long-wavelength thermal imagery by exploiting the differential heating histories of ground points in the vicinity of shadows. The use of differential heating histories of different ground points of the same surface material allows the use of a single image acquisition step to provide the necessary variation in measured parameters for calculation of the thermal properties of surface materials.

  4. Investigation of a Polarization Controller in Titanium Diffused Lithium Niobate Waveguide near 1530 nm Wavelength

    E-Print Network [OSTI]

    Sung, Won Ju

    2013-12-10T23:59:59.000Z

    INVESTIGATION OF A POLARIZATION CONTROLLER IN TITANIUM DIFFUSED LITHIUM NIOBATE WAVEGUIDE NEAR 1530 NM WAVELENGTH A Dissertation by WON JU SUNG Submitted to the Office of Graduate and Professional Studies of Texas A&M University... systems are being commercialized [1-3], and efforts for 400G modulators are being pursued [1, 4]. Various materials have been explored for high speed devices need [5, 6], and lithium niobate remains the most attractive choice currently [7]. Fiber...

  5. A Study of Wavelength Calibration of NEWSIPS High-Dispersion Spectra

    E-Print Network [OSTI]

    Myron A. Smith

    2001-04-03T23:59:59.000Z

    In this study we cross-correlate many IUE echellograms of a variety of stars to evaluate systematic error sources in the wavelength zeropoint of all three cameras. We first evaluated differences between the final archived ("NEWSIPS") and the originally processed ("IUESIPS") spectra. These show a clear time dependence in zeropoint for the SWP camera due to revisions in the IUESIPS wavelength scale. Small IUESIPS - NEWSIPS differences are also found for the LWR camera. We also examined wavelength zeropoint disparities between data obtained both through the small and large entrance apertures and for observations made by different target acquisition modes for faint and bright stars. We found that velocities resulting from these alternative observing modes are nil. For large-aperture observations the dominant error source is the target position placement in the aperture. We searched for spurious trends with time, and found only a suggestion of time trends for faint stars observed with the SWP camera. We also discovered 1-day, +/-3 km/s sinusoidsal patterns in intensive monitoring data which are ascribable to changes in telescope focus resulting from thermal drifts. In the second part of the paper, we measured mean zeropoint errors of NEWSIPS echellogram data against laboratory results by using the GHRS spectral atlas of the 10 Lac. We find that the derived apparent velocity difference for this star is -1 +/-3.5 km/s. Several less precise comparisons lead to similar results. The zeropoints of the NEWSIPS-processed LWP/LWR cameras are evaluated and are also found to be nearly zero (+/-5 km/s) relative to HST atlases of Arcturus and Procyon atlas. These results do not support result by Gonzalez-Riestra et al. that corrections should be introduced to the wavelength scales of various NEWSIPS high-dispersion data products.

  6. High gain, Fast Scan, Broad Spectrum Parallel Beam Wavelength Dispersive X-ray Spectrometer for SEM

    SciTech Connect (OSTI)

    OHara, David

    2009-05-08T23:59:59.000Z

    During contract # DE-FG02-ER83545, Parallax Research, Inc. developed a High gain, Fast Scan Broad Spectrum Parallel beam Wavelength Dispersive X-ray Spectrometer for use on Scanning Electron Microscopes (SEM). This new spectrometer allows very fast high resolution elemental analysis of samples in an electron microscope. By comparison to previous WDS spectrometers, it can change from one energy position to another very quickly and has an extended range compared to some similar products.

  7. Chemical analysis of uranium-niobium alloys by wavelength dispersive spectroscopy at the sigma complex

    SciTech Connect (OSTI)

    Papin, Pallas A.

    2012-06-01T23:59:59.000Z

    Uranium-niobium alloys play an important role in the nation's nuclear stockpile. It is possible to chemically quantify this alloy at a micron scale by using a technique know as wavelength dispersive spectroscopy. This report documents how this technique was used and how it is possible to reproduce measurements of this type. Discussion regarding the accuracy and precision of the measurements, the development of standards, and the comparison of different ways to model the matrices are all presented.

  8. Chemical detection and laser wavelength stabilization employing spectroscopic absorption via laser compliance voltage sensing

    DOE Patents [OSTI]

    Taubman, Matthew S; Phillips, Mark C

    2014-03-18T23:59:59.000Z

    Systems and methods are disclosed that provide a direct indication of the presence and concentration of an analyte within the external cavity of a laser device that employ the compliance voltage across the laser device. The systems can provide stabilization of the laser wavelength. The systems and methods can obviate the need for an external optical detector, an external gas cell, or other sensing region and reduce the complexity and size of the sensing configuration.

  9. Semester, Academic Year and Short Term SUNY Programs

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    Semester, Academic Year and Short Term SUNY Programs: Asia #12;1 Table of Contents How to Use Year 10 Japan Short-term 12 Korea Semester & Academic Year 13 Korea Short-term 17 Programs in Other Contact Information 23 How to Use this Booklet This handout contains listings of all the programs offered

  10. Short-term energy outlook quarterly projections. First quarter 1994

    SciTech Connect (OSTI)

    Not Available

    1994-02-07T23:59:59.000Z

    The Energy Information Administration (EIA) prepares quarterly, short- term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets.

  11. ORIGINAL PAPER Introduction to the Special Issues: Short-term

    E-Print Network [OSTI]

    Olufsen, Mette Sofie

    in short-term cardiovascular­respiratory regulation, (ii) to develop mathematical models that can improve involved in short-term cardio- vascular­respiratory control include auto-regulation of vasculature, controlORIGINAL PAPER Introduction to the Special Issues: Short-term Cardiovascular­Respiratory Control

  12. Do short sale transactions precede bad news events?* Holger Daske

    E-Print Network [OSTI]

    Kearns, Michael

    , 2005 Current Draft: October 18, 2005 ABSTRACT: Do short sale transactions precede bad news eventsDo short sale transactions precede bad news events?* Holger Daske Scott A. Richardson rem Tuna? Not recently. This paper examines short sale transactions around significant news events. Using a novel

  13. Final Report 527 Economic Impact Analysis of Short Line Railroads

    E-Print Network [OSTI]

    Stephens, Jacqueline

    railroads. First described is the scope and presence of the eleven short line railroads currently operatingFinal Report 527 Economic Impact Analysis of Short Line Railroads by Jared J. Llorens, Ph.D. James's Catalog No. 4. Title and Subtitle Economic Impact Analysis of Short Line Railroads 5. Report Date October

  14. Multi-wavelength analysis of high energy electrons in solar flares: a case study of August 20, 2002 flare

    E-Print Network [OSTI]

    J. Kasparova; M. Karlicky; E. P. Kontar; R. A. Schwartz; B. R. Dennis

    2005-08-30T23:59:59.000Z

    A multi-wavelength spatial and temporal analysis of solar high energy electrons is conducted using the August 20, 2002 flare of an unusually flat (gamma=1.8) hard X-ray spectrum. The flare is studied using RHESSI, Halpha, radio, TRACE, and MDI observations with advanced methods and techniques never previously applied in the solar flare context. A new method to account for X-ray Compton backscattering in the photosphere (photospheric albedo) has been used to deduce the primary X-ray flare spectra. The mean electron flux distribution has been analysed using both forward fitting and model independent inversion methods of spectral analysis. We show that the contribution of the photospheric albedo to the photon spectrum modifies the calculated mean electron flux distribution, mainly at energies below 100 keV. The positions of the Halpha emission and hard X-ray sources with respect to the current-free extrapolation of the MDI photospheric magnetic field and the characteristics of the radio emission provide evidence of the closed geometry of the magnetic field structure and the flare process in low altitude magnetic loops. In agreement with the predictions of some solar flare models, the hard X-ray sources are located on the external edges of the Halpha emission and show chromospheric plasma heated by the non-thermal electrons. The fast changes of Halpha intensities are located not only inside the hard X-ray sources, as expected if they are the signatures of the chromospheric response to the electron bombardment, but also away from them.

  15. Black holes and the absorption rate of cosmological scalar fields

    E-Print Network [OSTI]

    L. Arturo Urena-Lopez; Lizbeth M. Fernandez

    2011-07-15T23:59:59.000Z

    We study the absorption of a massless scalar field by a static black hole. Using the continuity equation that arises from the Klein-Gordon equation, it is possible to define a normalized absorption rate $\\Gamma(t)$ for the scalar field as it falls into the black hole. It is found that the absorption mainly depends upon the characteristics wavelengths involved in the physical system: the mean wavenumber and the width of the wave packet, but that it is insensitive to the scalar field's strength. By taking a limiting procedure, we determine the minimum absorption fraction of the scalar field's mass by the black hole, which is around 50%.

  16. Sensitivity enhancement of grating interferometer based two-dimensional sensor arrays using two-wavelength readout

    SciTech Connect (OSTI)

    Ferhanoglu, Onur; Urey, Hakan

    2011-07-01T23:59:59.000Z

    Diffraction gratings integrated with microelectromechanical systems (MEMS) sensors offer displacement measurements with subnanometer sensitivity. However, the sensitivity of the interferometric readout may drop significantly based on the gap between the grating and the reference surface. A two-wavelength (2-{lambda}) readout method was previously tested using a single MEMS sensor for illustrating increased displacement measurement capability. This work demonstrates sensitivity enhancement on a sensor array with large scale parallelization ({approx}20,000 sensors). The statistical representation, which is developed to model sensitivity enhancement within a grating based sensor array, is supported by experimental results using a thermal sensor array. In the experiments, two lasers at different wavelengths (633 and 650 nm) illuminate the thermal sensor array from the backside, time-sequentially. The diffracted first order light from the array is imaged onto a single CCD camera. The target scene is reconstructed by observing the change in the first diffracted order diffraction intensity for both wavelengths. Merging of the data from two measurements with two lasers was performed by taking the larger of the two CCD measurements with respect to the reference image for each sensor. {approx}30% increase in the average sensitivity was demonstrated for a 160x120 pixel IR sensor array. Proposed architecture is also applicable to a variety of sensing applications, such as parallel biosensing and atomic force microscopy, for improved displacement measurements and enhanced sensitivity.

  17. Hot spot generation in energetic materials created by long-wavelength infrared radiation

    SciTech Connect (OSTI)

    Chen, Ming-Wei; You, Sizhu; Suslick, Kenneth S.; Dlott, Dana D., E-mail: dlott@illinois.edu [School of Chemical Sciences and Fredrick Seitz Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

    2014-02-10T23:59:59.000Z

    Hot spots produced by long-wavelength infrared (LWIR) radiation in an energetic material, crystalline RDX (1,3,5-trinitroperhydro-1,3,5-triazine), were studied by thermal-imaging microscopy. The LWIR source was a CO{sub 2} laser operating in the 28-30?THz range. Hot spot generation was studied using relatively low intensity (?100?W cm{sup ?2}), long-duration (450 ms) LWIR pulses. The hot spots could be produced repeatedly in individual RDX crystals, to investigate the fundamental mechanisms of hot spot generation by LWIR, since the peak hot-spot temperatures were kept to ?30?K above ambient. Hot spots were generated preferentially beneath RDX crystal planes making oblique angles with the LWIR beam. Surprisingly, hot spots were more prominent when the LWIR wavelength was tuned to be weakly absorbed (absorption depth ?30??m) than when the LWIR wavelength was strongly absorbed (absorption depth ?5??m). This unexpected effect was explained using a model that accounts for LWIR refraction and RDX thermal conduction. The weakly absorbed LWIR is slightly focused underneath the oblique crystal planes, and it penetrates the RDX crystals more deeply, increasing the likelihood of irradiating RDX defect inclusions that are able to strongly absorb or internally focus the LWIR beam.

  18. Plasma diagnostic potential of 2p4f in N$^+$ -- accurate wavelengths and oscillator strengths

    E-Print Network [OSTI]

    Shen, Xiaozhi; Jönsson, Per; Wang, Jianguo

    2015-01-01T23:59:59.000Z

    Radiative emission lines from nitrogen and its ions are often observed in nebulae spectra, where the N$^{2+}$ abundance can be inferred from lines of the 2p4f configuration. In addition, intensity ratios between lines of the 2p3p -- 2p3s and 2p4f -- 2p3d transition arrays can serve as temperature diagnostics. To aid abundance determinations and plasma diagnostics, wavelengths and oscillator strengths were calculated with high-precision for electric-dipole (E1) transitions from levels in the 2p4f configuration of N$^{+}$. Electron correlation and relativistic effects, including the Breit interaction, were systematically taken into account within the framework of the multiconfiguration Dirac-Hartree-Fock (MCDHF) method. Except for the 2p4f - 2p4d transitions with quite large wavelengths and the two-electron-one-photon 2p4f -2s2p$^3$ transitions, the uncertainties of the present calculations were controlled to within 3% and 5% for wavelengths and oscillator strengths, respectively. We also compared our results w...

  19. MINERAL PROCESSING BY SHORT CIRCUITS IN PROTOPLANETARY DISKS

    SciTech Connect (OSTI)

    McNally, Colin P. [Niels Bohr International Academy, Niels Bohr Institute, DK-2100 Copenhagen (Denmark); Hubbard, Alexander; Mac Low, Mordecai-Mark [Department of Astrophysics, American Museum of Natural History, New York, NY 10024-5192 (United States); Ebel, Denton S. [Department of Earth and Planetary Sciences, American Museum of Natural History, New York, NY 10024-5192 (United States); D'Alessio, Paola, E-mail: cmcnally@nbi.dk, E-mail: ahubbard@amnh.org, E-mail: mordecai@amnh.org, E-mail: debel@amnh.org, E-mail: p.dalessio@crya.unam.mx [Centro de Radioastronomia y Astrofisica, Universidad Nacional Autonoma de Mexico, 58089 Morelia, MICH (Mexico)

    2013-04-10T23:59:59.000Z

    Meteoritic chondrules were formed in the early solar system by brief heating of silicate dust to melting temperatures. Some highly refractory grains (Type B calcium-aluminum-rich inclusions, CAIs) also show signs of transient heating. A similar process may occur in other protoplanetary disks, as evidenced by observations of spectra characteristic of crystalline silicates. One possible environment for this process is the turbulent magnetohydrodynamic flow thought to drive accretion in these disks. Such flows generally form thin current sheets, which are sites of magnetic reconnection, and dissipate the magnetic fields amplified by a disk dynamo. We suggest that it is possible to heat precursor grains for chondrules and other high-temperature minerals in current sheets that have been concentrated by our recently described short-circuit instability. We extend our work on this process by including the effects of radiative cooling, taking into account the temperature dependence of the opacity; and by examining current sheet geometry in three-dimensional, global models of magnetorotational instability. We find that temperatures above 1600 K can be reached for favorable parameters that match the ideal global models. This mechanism could provide an efficient means of tapping the gravitational potential energy of the protoplanetary disk to heat grains strongly enough to form high-temperature minerals. The volume-filling nature of turbulent magnetic reconnection is compatible with constraints from chondrule-matrix complementarity, chondrule-chondrule complementarity, the occurrence of igneous rims, and compound chondrules. The same short-circuit mechanism may perform other high-temperature mineral processing in protoplanetary disks such as the production of crystalline silicates and CAIs.

  20. Sensor for detecting changes in magnetic fields

    DOE Patents [OSTI]

    Praeg, W.F.

    1980-02-26T23:59:59.000Z

    A sensor is described for detecting changes in the magnetic field of the equilibrium-field coil of a Tokamak plasma device that comprises a pair of bifilar wires disposed circumferentially, one inside and one outside the equilibrium-field coil. Each is shorted at one end. The difference between the voltages detected at the other ends of the bifilar wires provides a measure of changing flux in the equilibrium-field coil. This difference can be used to detect faults in the coil in time to take action to protect the coil.

  1. Sensor for detecting changes in magnetic fields

    DOE Patents [OSTI]

    Praeg, Walter F. (Palos Park, IL)

    1981-01-01T23:59:59.000Z

    A sensor for detecting changes in the magnetic field of the equilibrium-field coil of a Tokamak plasma device comprises a pair of bifilar wires disposed circumferentially, one inside and one outside the equilibrium-field coil. Each is shorted at one end. The difference between the voltages detected at the other ends of the bifilar wires provides a measure of changing flux in the equilibrium-field coil. This difference can be used to detect faults in the coil in time to take action to protect the coil.

  2. Nonlinear excitation of photonikos and plasmons by high-power, short pulse lasers

    E-Print Network [OSTI]

    Levan N. Tsintsadze; Hitoshi Hojo

    2008-10-29T23:59:59.000Z

    Modulational excitation of longitudinal photons (photonikos) and electron Langmuir waves, as well as ion sound waves by an incoherent strong and superstrong radiation (high-power short pulse lasers, non-thermal equilibrium cosmic field radiation, etc.) in plasmas are investigated. A simultaneous generation of photonikos and plasmons are demonstrated. Furthermore, the kinetic instability is considered when a low frequency photonikos are generated alone. Growth rates of these new modes are obtained.

  3. Short communication Satellite-derived surface water pCO2 and airsea CO2 fluxes

    E-Print Network [OSTI]

    Short communication Satellite-derived surface water pCO2 and air­sea CO2 fluxes in the northern for the estimation of the partial pressure of carbon dioxide (pCO2) and air­sea CO2 fluxes in the northern South), respectively, the monthly pCO2 fields were computed. The derived pCO2 was compared with the shipboard pCO2

  4. Modulation and kinematics of mechanically-generated short gravity waves riding on long waves

    E-Print Network [OSTI]

    Spell, Charles Anthony

    1992-01-01T23:59:59.000Z

    for the degree of MASTER OF SCIENCE December 1992 Major Subject: Ocean Engineering MODULATION AND KINEMATICS OF MECHANICALLY- GENERATED SHORT GRAVITY WAVES RIDING ON LONG WAVES A Thesis by C~S ANTHONY SPELL Approved as to style and content by: Jun Zhang... fundamental nonlinear wave interaction occurring in an irregular wave field. The objectives of the present study are now stated: ~ Generate a dual-component wave formed from the interaction of two inde- pendently propagating monochromatic wave trains in a...

  5. Short-term energy outlook, January 1999

    SciTech Connect (OSTI)

    NONE

    1999-01-01T23:59:59.000Z

    The Energy Information Administration (EIA) prepares the Short-Term Energy Outlook (energy supply, demand, and price projections) monthly. The forecast period for this issue of the Outlook extends from January 1999 through December 2000. Data values for the fourth quarter 1998, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the January 1999 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 28 figs., 19 tabs.

  6. Short-term energy outlook, July 1998

    SciTech Connect (OSTI)

    NONE

    1998-07-01T23:59:59.000Z

    The Energy Information Administration (EIA) prepares The Short-Term Energy Outlook (energy supply, demand, and price projections) monthly for distribution on the internet at: www.eia.doe.gov/emeu/steo/pub/contents.html. In addition, printed versions of the report are available to subscribers in January, April, July and October. The forecast period for this issue of the Outlook extends from July 1998 through December 1999. Values for second quarter of 1998 data, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the July 1998 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. 28 figs., 19 tabs.

  7. Thermal Casimir drag in fluctuating classical fields

    E-Print Network [OSTI]

    V. Démery; D. S. Dean

    2011-04-14T23:59:59.000Z

    A uniformly moving inclusion which locally suppresses the fluctuations of a classical thermally excited field is shown to experience a drag force which depends on the dynamics of the field. It is shown that in a number of cases the linear friction coefficient is dominated by short distance fluctuations and takes a very simple form. Examples where this drag can occur are for stiff objects, such as proteins, nonspecifically bound to more flexible ones such as polymers and membranes.

  8. Field Guide

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField8,Dist.New Mexico Feb. 13,Conservation BillingFieldField

  9. Effective Field Theory and Finite Density Systems

    E-Print Network [OSTI]

    R. J. Furnstahl; G. Rupak; T. Schaefer

    2008-01-04T23:59:59.000Z

    This review gives an overview of effective field theory (EFT) as applied at finite density, with a focus on nuclear many-body systems. Uniform systems with short-range interactions illustrate the ingredients and virtues of many-body EFT and then the varied frontiers of EFT for finite nuclei and nuclear matter are surveyed.

  10. Method and apparatus for generating high power laser pulses in the two to six micron wavelength range

    DOE Patents [OSTI]

    MacPherson, D.C.; Nelson, L.D.; O`Brien, M.J.

    1996-12-10T23:59:59.000Z

    Apparatus performs a method of generating one or more output laser pulses in a range of 2 to 6 microns. When a plurality of the output laser pulses are generated, a first output pulse has any selected wavelength within the range and a second output pulse is temporally closely spaced relative to the first output pulse and has a chosen wavelength differing from the selected wavelength. An oscillator laser cavity is provided with a tunable oscillator rod capable of generating initial laser pulses within a range of from 750 to 1000 nm, and a tuning element is coupled to the rod. A flashlamp is operable to pump the rod. For two pulse operation, the flashlamp has a given duration. A Q-switch provides the initial laser pulses upon operation of the tuning element and the flashlamp. A Raman device coupled to the rod shifts the wavelength of such initial laser pulse into the range of from 2 to 6 microns to form the output laser pulse having a wavelength within the range. For multiple pulses, a controller causes the Q-switch to provide first and second ones of the initial laser pulses, spaced by a time interval less than the given duration. Also, a selector coupled to the tuning element is operable within such duration to successively select the wavelength of the first output pulse and the chosen wavelength of the second initial pulse. The Raman device is responsive to each of the initial light pulses to generate radiation at first and second Stokes wavelengths, each of said the output laser pulses being radiation at the second Stokes wavelength. 30 figs.

  11. Tachyonic field interacting with Scalar (Phantom) Field

    E-Print Network [OSTI]

    Surajit Chattopadhyay; Ujjal Debnath

    2009-01-29T23:59:59.000Z

    In this letter, we have considered the universe is filled with the mixture of tachyonic field and scalar or phantom field. If the tachyonic field interacts with scalar or phantom field, the interaction term decays with time and the energy for scalar field is transferred to tachyonic field or the energy for phantom field is transferred to tachyonic field. The tachyonic field and scalar field potentials always decrease, but phantom field potential always increases.

  12. Space-resolved extreme ultraviolet spectroscopy free of high-energy neutral particle noise in wavelength range of 10–130 Å on the large helical device

    SciTech Connect (OSTI)

    Huang, Xianli, E-mail: huang.xianli@nifs.ac.jp [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan)] [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan); Morita, Shigeru; Oishi, Tetsutarou; Goto, Motoshi [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan) [Department of Fusion Science, Graduate University for Advanced Studies, Toki 509-5292 Gifu (Japan); National Institute for Fusion Science, Toki 509-5292 Gifu (Japan); Dong, Chunfeng [Southwestern Institute of Physics, P.O. Box 432, Chengdu, Sichuan 610041 (China)] [Southwestern Institute of Physics, P.O. Box 432, Chengdu, Sichuan 610041 (China)

    2014-04-15T23:59:59.000Z

    A flat-field space-resolved extreme ultraviolet (EUV) spectrometer system working in wavelength range of 10–130 Å has been constructed in the Large Helical Device (LHD) for profile measurements of bremsstrahlung continuum and line emissions of heavy impurities in the central column of plasmas, which are aimed at studies on Z{sub eff} and impurity transport, respectively. Until now, a large amount of spike noise caused by neutral particles with high energies (?180 keV) originating in neutral beam injection has been observed in EUV spectroscopy on LHD. The new system has been developed with an aim to delete such a spike noise from the signal by installing a thin filter which can block the high-energy neutral particles entering the EUV spectrometer. Three filters of 11 ?m thick beryllium (Be), 3.3 ?m thick polypropylene (PP), and 0.5 ?m thick polyethylene terephthalate (PET: polyester) have been examined to eliminate the spike noise. Although the 11 ?m Be and 3.3 ?m PP filters can fully delete the spike noise in wavelength range of ? ? 20 Å, the signal intensity is also reduced. The 0.5 ?m PET filter, on the other hand, can maintain sufficient signal intensity for the measurement and the spike noise remained in the signal is acceptable. As a result, the bremsstrahlung profile is successfully measured without noise at 20 Å even in low-density discharges, e.g., 2.9 × 10{sup 13} cm{sup ?3}, when the 0.5 ?m PET filter is used. The iron n = 3–2 L? transition array consisting of FeXVII to FeXXIV is also excellently observed with their radial profiles in wavelength range of 10–18 Å. Each transition in the L? array can be accurately identified with its radial profile. As a typical example of the method a spectral line at 17.62 Å is identified as FeXVIII transition. Results on absolute intensity calibration of the spectrometer system, pulse height and noise count analyses of the spike noise between holographic and ruled gratings and wavelength response of the used filters are also presented with performance of the present spectrometer system.

  13. Short Range Correlations and the EMC Effect

    SciTech Connect (OSTI)

    L.B. Weinstein, E. Piasetzky, D.W. Higinbotham, J. Gomez, O. Hen, R. Shneor

    2011-02-01T23:59:59.000Z

    This Letter shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering at intermediate xB, 0.35?xB?0.7, is linearly related to the short range correlation (SRC) scale factor obtained from electron inclusive scattering at xB?1. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free pn pair cross sections and F2n/F2p, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

  14. Short Range Correlations and the EMC Effect

    E-Print Network [OSTI]

    L. B. Weinstein; E. Piasetzky; D. W. Higinbotham; J. Gomez; O. Hen; R. Shneor

    2011-01-18T23:59:59.000Z

    This paper shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering (DIS) at intermediate $x_B$, $0.35\\le x_B\\le 0.7$, is linearly related to the Short Range Correlation (SRC) scaling factor obtained from electron inclusive scattering at $x_B\\ge 1.$. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free $pn$ pair cross sections, the DIS cross section for a free neutron, and $F_2^n/F_2^p$, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

  15. Short Range Correlations and the EMC Effect

    SciTech Connect (OSTI)

    Weinstein, L. B. [Old Dominion University, Norfolk, Virginia 23529 (United States); Piasetzky, E.; Hen, O.; Shneor, R. [Tel Aviv University, Tel Aviv 69978 (Israel); Higinbotham, D. W.; Gomez, J. [Thomas Jefferson National Accelerator Facility, Newport News, Virginia 23606 (United States)

    2011-02-04T23:59:59.000Z

    This Letter shows quantitatively that the magnitude of the EMC effect measured in electron deep inelastic scattering at intermediate x{sub B}, 0.35{<=}x{sub B{<=}}0.7, is linearly related to the short range correlation (SRC) scale factor obtained from electron inclusive scattering at x{sub B{>=}}1. The observed phenomenological relationship is used to extract the ratio of the deuteron to the free pn pair cross sections and F{sub 2}{sup n}/F{sub 2}{sup p}, the ratio of the free neutron to free proton structure functions. We speculate that the observed correlation is because both the EMC effect and SRC are dominated by the high virtuality (high momentum) nucleons in the nucleus.

  16. Insulation spacer eliminates electric shorts between lines

    SciTech Connect (OSTI)

    Colaizzi, J.F.; Rockafellow, G.B.

    1983-03-01T23:59:59.000Z

    The design criteria incorporated into the pipeline insulating spacer were: spacer material selected must have a very large compressive and tensile strength in order to withstand the weight and stress resulting on the pipelines; provide the necessary abrasive resistance, dielectric strength, and will not decay underground; must not soften with heat when used around or near stream lines or will not cold flow under pressure; minimum length and circumference to reduce ''Shielding Effects'' from any cathodic protection system; and provide a material that incorporates a maximum strength at a minimum thickness. Explains that electric shorts are caused by 2 or more metallic structures in contact with each other. Notes that the insulating spacer's use has been expanded to provide electrical and physical insulation between carrier pipe and casing, supports for piping in compressing stations, and for pipelines that are suspended on bridges.

  17. Earth Planets Space, 57, 895902, 2005 Short time-scale heating of the Earth's mantle by ice-sheet dynamics

    E-Print Network [OSTI]

    Hanyk, Ladislav

    by modeling the linear response of a self-gravitating viscoelastic planet, the gravity field anoma- lies haveEarth Planets Space, 57, 895­902, 2005 Short time-scale heating of the Earth's mantle by ice-scale energy transfer from the ice sheet loading and unloading processes to the Earth's interior via viscous

  18. GaSb substrates with extended IR wavelength for advanced space based applications

    SciTech Connect (OSTI)

    Allen, Lisa P.; Flint, Patrick; Dallas, Gordon; Bakken, Daniel; Blanchat, Kevin; Brown, Gail J.; Vangala, Shivashankar R.; Goodhue, William D.; Krishnaswami, Kannan

    2009-05-01T23:59:59.000Z

    GaSb substrates have advantages that make them attractive for implementation of a wide range of infrared (IR) detectors with higher operating temperatures for stealth and space based applications. A significant aspect that would enable widespread commercial application of GaSb wafers for very long wavelength IR (VLWIR) applications is the capability for transmissivity beyond 15 m. Due largely to the GaSb (antisite) defect and other point defects in undoped GaSb substrates, intrinsic GaSb is still slightly p-type and strongly absorbs in the VLWIR. This requires backside thinning of the GaSb substrate for IR transmissivity. An extremely low n-type GaSb substrate is preferred to eliminate thinning and provide a substrate solution for backside illuminated VLWIR devices. By providing a more homogeneous radial distribution of the melt solute to suppress GaSb formation and controlling the cooling rate, ultra low doped n:GaSb has been achieved. This study examines the surface properties and IR transmission spectra of ultra low doped GaSb substrates at both room and low temperatures. Atomic force microscopy (AFM), homoepitaxy by MBE, and infrared Fourier transform (FTIR) analysis was implemented to examine material quality. As compared with standard low doped GaSb, the ultra low doped substrates show over 50% transmission and consistent wavelength transparency past 23 m with improved %T at low temperature. Homoepitaxy and AFM results indicate the ultra low doped GaSb has a low thermal desorbtion character and qualified morphology. In summary, improvements in room temperature IR transmission and extended wavelength characteristics have been shown consistently for ultra low doped n:GaSb substrates.

  19. THE CHANDRA MULTI-WAVELENGTH PROJECT: OPTICAL SPECTROSCOPY AND THE BROADBAND SPECTRAL ENERGY DISTRIBUTIONS OF X-RAY-SELECTED AGNs

    E-Print Network [OSTI]

    Trichas, Markos

    From optical spectroscopy of X-ray sources observed as part of the Chandra Multi-wavelength Project (ChaMP), we present redshifts and classifications for a total of 1569 Chandra sources from our targeted spectroscopic ...

  20. Long wavelength, high gain InAsSb strained-layer superlattice photoconductive detectors

    DOE Patents [OSTI]

    Biefeld, Robert M. (Albuquerque, NM); Dawson, L. Ralph (Albuquerque, NM); Fritz, Ian J. (Albuquerque, NM); Kurtz, Steven R. (Albuquerque, NM); Zipperian, Thomas E. (Albuquerque, NM)

    1991-01-01T23:59:59.000Z

    A high gain photoconductive device for 8 to 12 .mu.m wavelength radiation including an active semiconductor region extending from a substrate to an exposed face, the region comprising a strained-layer superlattice of alternating layers of two different InAs.sub.1-x Sb.sub.x compounds having x>0.75. A pair of spaced electrodes are provided on the exposed face, and changes in 8 to 12 .mu.m radiation on the exposed face cause a large photoconductive gain between the spaced electrodes.

  1. Wavelength calibration of x-ray imaging crystal spectrometer on Joint Texas Experimental Tokamak

    SciTech Connect (OSTI)

    Yan, W.; Chen, Z. Y., E-mail: zychen@hust.edu.cn; Jin, W.; Huang, D. W.; Ding, Y. H.; Li, J. C.; Zhang, X. Q.; Zhuang, G. [School of Electrical and Electronic Engineering, Huazhong University of Science and Technology, Wuhan (China); Lee, S. G.; Shi, Y. J. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

    2014-11-15T23:59:59.000Z

    The wavelength calibration of x-ray imaging crystal spectrometer is a key issue for the measurements of plasma rotation. For the lack of available standard radiation source near 3.95 Å and there is no other diagnostics to measure the core rotation for inter-calibration, an indirect method by using tokamak plasma itself has been applied on joint Texas experimental tokamak. It is found that the core toroidal rotation velocity is not zero during locked mode phase. This is consistent with the observation of small oscillations on soft x-ray signals and electron cyclotron emission during locked-mode phase.

  2. Superconducting nanowire single-photon detectors at a wavelength of 940 nm

    E-Print Network [OSTI]

    Zhang, W J; You, L X; He, Y H; Zhang, L; Liu, X Y; Yang, X Y; Wu, J J; Guo, Q; Chen, S J; Wang, Z; Xie, X M

    2015-01-01T23:59:59.000Z

    We develop single-photon detectors comprising single-mode fiber-coupled superconducting nanowires, with high system detection efficiencies at a wavelength of 940 nm. The detector comprises a 6.5-nm-thick, 110-nm-wide NbN nanowire meander fabricated onto a Si substrate with a distributed Bragg reflector for enhancing the optical absorptance. We demonstrate that, via the design of a low filling factor (1/3) and active area ({\\Phi} = 10 {\\mu}m), the system reaches a detection efficiency of ~60% with a dark count rate of 10 Hz, a recovery time <12 ns, and a timing jitter of ~50 ps.

  3. A Multi-Anode Photomultiplier Tube Based Wavelength-Shifting-Fiber Detector for neutron diffraction

    SciTech Connect (OSTI)

    Berry, Kevin D [ORNL; Clonts, Lloyd G [ORNL; Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Funk, Loren L [ORNL; Hannan, Bruce W [ORNL; Hodges, Jason P [ORNL; Riedel, Richard A [ORNL; Wang, Cai-Lin [ORNL

    2012-01-01T23:59:59.000Z

    The wavelength-shifting (WLS) fiber scintillator neutron detectors were developed for two time-of-flight (TOF) neutron powder diffractometers (POWGEN, VULCAN) at Spallation Neutron Source (SNS). In a recent module (v3.0), however, there are 32 1-inch-diameter photomultiplier tubes (PMTs) which are bulky and expensive. We built a new detector module (v3.1) based on four multi-anode (MA) PMTs, and tested its performance including detection efficiency, count rate capability, spatial resolution, ghosting properties, and gamma-ray sensitivity. The v3.1 module was compared with two prior v3.0 modules, and 3He tube detectors.

  4. The optical applications of 3D sub-wavelength block-copolymer nanostructured functional materials

    E-Print Network [OSTI]

    Poole, Zsolt; Ohodnicki, Paul; Chen, Kevin

    2015-01-01T23:59:59.000Z

    A method to engineer the refractive indices of functional materials (TiO2, ZnO, SnO2, SiO2), by nanostructuring in the deep sub-wavelength regime (optical design techniques such as thin film optimization methods, transformation optics and conformal mapping. Refractive index optimized multi-layer anti-reflection coatings on crystalline silicon, which reduce light reflections from 38% down to ~3% with a wide angular span, are demonstrated with the developed wet processing route. A high temperature oxygen free fiber optic hydrogen sensor realized by accessing nano-engine...

  5. Wavelength-Scale Imaging of Trapped Ions using a Phase Fresnel lens

    E-Print Network [OSTI]

    A. Jechow; E. W. Streed; B. G. Norton; M. J. Petrasiunas; D. Kielpinski

    2011-01-24T23:59:59.000Z

    A microfabricated phase Fresnel lens was used to image ytterbium ions trapped in a radio frequency Paul trap. The ions were laser cooled close to the Doppler limit on the 369.5 nm transition, reducing the ion motion so that each ion formed a near point source. By detecting the ion fluorescence on the same transition, near diffraction limited imaging with spot sizes of below 440 nm (FWHM) was achieved. This is the first demonstration of imaging trapped ions with a resolution on the order of the transition wavelength.

  6. The EMC Effect and Short-Range Correlations

    E-Print Network [OSTI]

    Misak M Sargsian

    2012-09-12T23:59:59.000Z

    We overview the progress made in studies of EMC and short range correlation (SRC) effects with the special emphasis given to the recent observation of the correlation between the slope of the EMC ratio at Bjorken x1 that measures the strength of the SRCs in nuclei. This correlation may indicate the larger modification of nucleons with higher momentum thus making the nucleon virtuality as the most relevant parameter of medium modifications. To check this conjecture we study the implication of several properties of high momentum component of the nuclear wave function on the characteristics of EMC effect. We observe two main reasons for the EMC-SRC correlation: first, the decrease of the contribution from the nuclear mean field due to the increase, with A, the fraction of the high momentum component of nuclear wave function. Second, the increase of the medium modification of nucleons in SRC. Our main prediction however is the increase of the proton contribution to the EMC effect for large A asymmetric nuclei. This prediction is based on the recent observation of the strong dominance of pn SRCs in the high momentum component of nuclear wave function. Our preliminary calculation based on this prediction of the excess of energetic and modified protons in large A nuclei describes reasonably well the main features of the observed EMC-SRC correlation.

  7. The EMC Effect and Short-Range Correlations

    E-Print Network [OSTI]

    Sargsian, Misak M

    2012-01-01T23:59:59.000Z

    We overview the progress made in studies of EMC and short range correlation (SRC) effects with the special emphasis given to the recent observation of the correlation between the slope of the EMC ratio at Bjorken x1 that measures the strength of the SRCs in nuclei. This correlation may indicate the larger modification of nucleons with higher momentum thus making the nucleon virtuality as the most relevant parameter of medium modifications. To check this conjecture we study the implication of several properties of high momentum component of the nuclear wave function on the characteristics of EMC effect. We observe two main reasons for the EMC-SRC correlation: first, the decrease of the contribution from the nuclear mean field due to the increase, with A, the fraction of the high momentum component of nuclear wave function. Second, the increase of the medium modification of nucleons in SRC. Our main prediction however is the increase of the proton contribution to the EMC effect for large A asymmetric nuclei. Th...

  8. Demographics of the Galaxies Hosting Short-duration Gamma-Ray Bursts

    E-Print Network [OSTI]

    Fong, Wen-fai; Chornock, Ryan; Margutti, Raffaella; Levan, Andrew J; Tanvir, Nial R; Tunnicliffe, Rachel L; Czekala, Ian; Fox, Derek B; Perley, Daniel A; Cenko, S Bradley; Zauderer, B Ashley; Laskar, Tanmoy; Persson, S Eric; Monson, Andrew J; Kelson, Daniel D; Birk, Christoph; Murphy, David; Servillat, Mathieu; Anglada, Guillem

    2013-01-01T23:59:59.000Z

    We present observations of the afterglows and host galaxies of three short-duration gamma-ray bursts (GRBs): 100625A, 101219A and 110112A. We find that GRB 100625A occurred in a z=0.452 early-type galaxy with a stellar mass of 4.6e9 M_Sun and a stellar population age of 0.7 Gyr, and GRB 101219A originated in a star-forming galaxy at z=0.718 with a stellar mass of 1.4e9 M_Sun, a star formation rate of 16 M_Sun yr^-1, and a stellar population age of 50 Myr. We also report the discovery of the optical afterglow of GRB 110112A, which lacks a coincident host galaxy to i>26 mag and we cannot conclusively identify any field galaxy as a possible host. The bursts have inferred circumburst densities of ~1e-4-1 cm^-3, and isotropic-equivalent gamma-ray and kinetic energies of 1e50-1e51 erg. These events highlight the diversity of galaxies that host short GRBs. To quantify this diversity, we use the sample of 36 Swift short GRBs with robust associations to an environment (~1/2 of 68 short bursts detected by Swift to May ...

  9. Cosmic-Ray Acceleration at Ultrarelativistic Shock Waves: Effects of Downstream Short-Wave Turbulence

    E-Print Network [OSTI]

    Jacek Niemiec; Michal Ostrowski; Martin Pohl

    2006-03-14T23:59:59.000Z

    The present paper is the last of a series studying the first-order Fermi acceleration processes at relativistic shock waves with the method of Monte Carlo simulations applied to shocks propagating in realistically modeled turbulent magnetic fields. The model of the background magnetic field structure of Niemiec & Ostrowski (2004, 2006) has been augmented here by a large-amplitude short-wave downstream component, imitating that generated by plasma instabilities at the shock front. Following Niemiec & Ostrowski (2006), we have considered ultrarelativistic shocks with the mean magnetic field oriented both oblique and parallel to the shock normal. For both cases simulations have been performed for different choices of magnetic field perturbations, represented by various wave power spectra within a wide wavevector range. The results show that the introduction of the short-wave component downstream of the shock is not sufficient to produce power-law particle spectra with the "universal" spectral index 4.2. On the contrary, concave spectra with cutoffs are preferentially formed, the curvature and cutoff energy being dependent on the properties of turbulence. Our results suggest that the electromagnetic emission observed from astrophysical sites with relativistic jets, e.g. AGN and GRBs, is likely generated by particles accelerated in processes other than the widely invoked first-order Fermi mechanism.

  10. A covariantly foliated higher dimensional space-time: Implications for short distance gravity and BSM physics

    E-Print Network [OSTI]

    Cao H. Nam

    2014-11-10T23:59:59.000Z

    We consider the space-time at short distances in which it is described by a $D$-dimensional manifold (bulk) carrying out the principal bundle structure. As a result, this space-time manifold is foliated in the covariant way by the $(D-4)$-dimensional submanifolds, realized as the space-like internal spaces, that are smooth copies of the Lie group $G$ considered in this paper as the special unitary group. The submanifolds being transversal to the internal spaces are realized as the external spaces and in fact identified as the usual $4$-dimensional world. The fundamental degrees of freedom determining the geometrical dynamics of the bulk corresponding with short distance gravity are given by the gauge fields, the external metric field and the modulus fields setting dynamically the volume of the internal spaces. These gauge fields laying the bulk is to point precisely out the local directions of the external spaces which depend on the topological non-triviality of the space-time principal bundle. The physical size of the internal spaces is fixed dynamically by the moduli stabilization potential which completely arise from the intrinsic geometry of the bulk. A detail description of the low energy bulk gravity in the weak field limit is given around the classical ground state of the bulk. Additionally, we investigate the dynamics of the fundamentally $4$-dimensional Weyl spinor fields and the fields of carrying out the non-trivial representations of the Lie group $G$ propagating in the bulk in a detail study. These results suggest naturally the possible solutions to some the experimental problems of Standard Model, the smallness of the observed neutrino masses and a dark matter candidate.

  11. Short GRBs: Rates and luminosity function implications

    E-Print Network [OSTI]

    Dafne Guetta

    2006-10-13T23:59:59.000Z

    We compare the luminosity function and rate inferred from the BATSE short hard bursts (SHBs) peak flux distribution with the redshift and luminosity distributions of SHBs observed by Swift/HETE II. The Swift/HETE II SHB sample is incompatible with SHB population that follows the star formation rate. However, it is compatible with a distribution of delay times after the SFR. This would be the case if SHBs are associated with the mergers of double neutron star (DNS) systems. DNS may be ``primordial'' or can form dynamically by binary exchange interaction in globular clusters during core collapse. The implied SHB rates that we find range from \\sim 8 to \\sim 30h_(70)^3 Gpc^(-3)yr^(-1). This rate is a much higher than what was previously estimated and, when beaming is taken into account, it is comparable to the rate of neutron star mergers estimated from statistics of binary pulsars. If GRBs are produced in mergers the implied rate practically guarantees detection by LIGO II and possibly even by LIGO I.

  12. Short-term energy outlook, April 1999

    SciTech Connect (OSTI)

    NONE

    1999-04-01T23:59:59.000Z

    The forecast period for this issue of the Outlook extends from April 1999 through December 2000. Data values for the first quarter 1999, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in EIA`s Weekly Petroleum Status Report) or are calculated from model simulations that use the latest exogenous information available (for example, electricity sales and generation are simulated by using actual weather data). The historical energy data, compiled in the April 1999 version of the Short-Term Integrated forecasting system (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS model is driven principally by three sets of assumptions or inputs: estimates of key macroeconomic variables, world oil price assumptions, and assumptions about the severity of weather. Macroeconomic estimates are produced by DRI/McGraw-Hill but are adjusted by EIA to reflect EIA assumptions about the world price of crude oil, energy product prices, and other assumptions which may affect the macroeconomic outlook. By varying the assumptions, alternative cases are produced by using the STIFS model. 25 figs., 19 tabs.

  13. Room temperature performance of mid-wavelength infrared InAsSb nBn detectors

    SciTech Connect (OSTI)

    Soibel, Alexander; Hill, Cory J.; Keo, Sam A.; Hoglund, Linda; Rosenberg, Robert; Kowalczyk, Robert; Khoshakhlagh, Arezou; Fisher, Anita; Ting, David Z.-Y.; Gunapala, Sarath D. [Jet Propulsion Laboratory, California Institute of Technology, 4800 Oak Grove Dr., Pasadena, California 91030 (United States)

    2014-07-14T23:59:59.000Z

    In this work, we investigate the high temperature performance of mid-wavelength infrared InAsSb-AlAsSb nBn detectors with cut-off wavelengths near 4.5??m. The quantum efficiency of these devices is 35% without antireflection coatings and does not change with temperature in the 77–325?K temperature range, indicating potential for room temperature operation. The current generation of nBn detectors shows an increase of operational bias with temperature, which is attributed to a shift in the Fermi energy level in the absorber. Analysis of the device performance shows that operational bias and quantum efficiency of these detectors can be further improved. The device dark current stays diffusion limited in the 150?K–325?K temperature range and becomes dominated by generation-recombination processes at lower temperatures. Detector detectivities are D*(?)?=?1?×?10{sup 9} (cm Hz{sup 0.5}/W) at T?=?300?K and D*(?)?=?5?×?10{sup 9} (cm Hz{sup 0.5}/W) at T?=?250?K, which is easily achievable with a one stage TE cooler.

  14. Antimonide-Based Long-Wavelength Lasers on GaAs Substrates

    SciTech Connect (OSTI)

    KLEM,JOHN F.; Blum, O.

    2000-08-17T23:59:59.000Z

    We have investigated the use of GaAsSb in edge-emitting laser active regions, in order to obtain lasing near 1.3 {micro}m. Single quantum well GaAsSb devices display electroluminescence at wavelengths as long as 1.34 {micro}m, but substantial blueshifts occur under high injection conditions. GaAsSb single quantum well edge emitters have been obtained which lase at 1.275 {micro}m with a room-temperature threshold current density as low as 535 A/cm{sup 2}. Modification of the basic GaAsSb/GaAs structure with the addition of InGaAs layers results in a strongly type-II band alignment which can be used to further extend the emission wavelength of these devices. Using GaAsSb/InGaAs active regions, lasers emitting at 1.17 {micro}m have been obtained with room-temperature threshold current densities of 120 A/cm{sup 2}, and devices operating at 1.29 {micro}m have displayed thresholds as low as 375 A/cm{sup 2}. Characteristic temperatures for devices employing various GaAsSb-based active regions have been measured to be 60-73 K.

  15. MULTI-WAVELENGTH OBSERVATIONS OF THE ENDURING TYPE IIn SUPERNOVAE 2005ip AND 2006jd

    SciTech Connect (OSTI)

    Stritzinger, Maximilian [Department of Physics and Astronomy, Aarhus University, Ny Munkegade 120, DK-8000 Aarhus C (Denmark); Taddia, Francesco; Fransson, Claes; Sollerman, Jesper [Oskar Klein Centre, Department of Astronomy, Stockholm University, AlbaNova, SE-10691 Stockholm (Sweden); Fox, Ori D. [Astrophysics Science Division, Observational Cosmology Laboratory, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Morrell, Nidia; Phillips, M. M.; Campillay, Abdo; Castellon, Sergio; Contreras, Carlos; Krzeminski, Wojtek [Carnegie Observatories, Las Campanas Observatory, Casilla 601, La Serena (Chile); Anderson, J. P.; Hamuy, Mario [Departamento de Astronomia, Universidad de Chile, Casilla 36D, Santiago (Chile); Boldt, Luis [Argelander Institut fuer Astronomie, Universitaet Bonn, Auf dem Huegel 71, D-53111 Bonn (Germany); Brown, Peter J. [Mitchell Institute for Fundamental Physics and Astronomy, Department of Physics and Astronomy, Texas A and M University, College Station, TX 77843 (United States); Folatelli, Gaston [Institute for the Physics and Mathematics of the Universe (IPMU), University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan); Habergham, S. M.; James, Phil A. [Astrophysics Research Institute, Liverpool John Moores University, Twelve Quays House, Egerton Wharf, Birkenhead CH41 1LD (United Kingdom); Hjorth, Jens [Dark Cosmology Centre, Niels Bohr Institute, University of Copenhagen, Juliane Maries Vej 30, DK-2100 Copenhagen O (Denmark); Mattila, Seppo [Tuorla Observatory, University of Turku, Vaeisaelaentie 20, FI-21500 Piikkioe (Finland); and others

    2012-09-10T23:59:59.000Z

    We present an observational study of the Type IIn supernovae (SNe IIn) 2005ip and 2006jd. Broadband UV, optical, and near-IR photometry, and visual-wavelength spectroscopy of SN 2005ip complement and extend upon published observations to 6.5 years past discovery. Our observations of SN 2006jd extend from UV to mid-infrared wavelengths, and like SN 2005ip, are compared to reported X-ray measurements to understand the nature of the progenitor. Both objects display a number of similarities with the 1988Z-like subclass of SN IIn including (1) remarkably similar early- and late-phase optical spectra, (2) a variety of high-ionization coronal lines, (3) long-duration optical and near-IR emission, and (4) evidence of cold and warm dust components. However, diversity is apparent, including an unprecedented late-time r-band excess in SN 2006jd. The observed differences are attributed to differences between the mass-loss history of the progenitor stars. We conclude that the progenitor of SN 2006jd likely experienced a significant mass-loss event during its pre-SN evolution akin to the great 19th century eruption of {eta} Carinae. Contrarily, as advocated by Smith et al., the circumstellar environment of SN 2005ip is found to be more consistent with a clumpy wind progenitor.

  16. Room temperature all-silicon photonic crystal nanocavity light emitting diode at sub-bandgap wavelengths

    E-Print Network [OSTI]

    Shakoor, A; Cardile, P; Portalupi, S L; Gerace, D; Welna, K; Boninelli, S; Franzo, G; Priolo, F; Krauss, T F; Galli, M; Faolain, L O

    2013-01-01T23:59:59.000Z

    Silicon is now firmly established as a high performance photonic material. Its only weakness is the lack of a native electrically driven light emitter that operates CW at room temperature, exhibits a narrow linewidth in the technologically important 1300- 1600 nm wavelength window, is small and operates with low power consumption. Here, an electrically pumped all-silicon nano light source around 1300-1600 nm range is demonstrated at room temperature. Using hydrogen plasma treatment, nano-scale optically active defects are introduced into silicon, which then feed the photonic crystal nanocavity to enahnce the electrically driven emission in a device via Purcell effect. A narrow ({\\Delta}{\\lambda} = 0.5 nm) emission line at 1515 nm wavelength with a power density of 0.4 mW/cm2 is observed, which represents the highest spectral power density ever reported from any silicon emitter. A number of possible improvements are also discussed, that make this scheme a very promising light source for optical interconnects a...

  17. THE SPECTRAL ENERGY DISTRIBUTION OF THE CARINA NEBULA FROM FAR-INFRARED TO RADIO WAVELENGTHS

    SciTech Connect (OSTI)

    Salatino, M.; De Bernardis, P.; Masi, S. [Physics Department, Sapienza Universita di Roma, p.le Aldo Moro 2, I-00185 Roma (Italy); Polenta, G., E-mail: maria.salatino@roma1.infn.it [ASI Science Data Center, ESRIN, via G. Galilei, I-00044, Frascati (Italy)

    2012-03-20T23:59:59.000Z

    Multi-wavelength observations are necessary for understanding the physical properties of astrophysical sources. In this paper, we use observations in the far-infrared to radio range to derive the spectral energy distribution (SED) of the Carina nebula. To do this, we carefully subtract the irregularly varying diffuse emission from the Galactic plane, which can be of the order of 10% of the nebula flux at these wavelengths. We find that the far-infrared SED can be modeled as emission from a dust population with a single temperature T{sub d} = (34.5{sup +2.0}{sub -1.8}) K and with a spectral index of emissivity {alpha} = -1.37{sup +0.09}{sub -0.08}. We also find a total infrared luminosity of the nebula of (7.4{sup +2.5}{sub -1.4}) Multiplication-Sign 10{sup 6} L{sub Sun} and, assuming a single temperature of the dust, a mass of the dust of (9500{sup +4600}{sub -3500}) M{sub Sun }.

  18. Quantum storage of entangled telecom-wavelength photons in an erbium-doped optical fibre

    E-Print Network [OSTI]

    Erhan Saglamyurek; Jeongwan Jin; Varun B. Verma; Matthew D. Shaw; Francesco Marsili; Sae Woo Nam; Daniel Oblak; Wolfgang Tittel

    2015-01-13T23:59:59.000Z

    The realization of a future quantum Internet requires processing and storing quantum information at local nodes, and interconnecting distant nodes using free-space and fibre-optic links. Quantum memories for light are key elements of such quantum networks. However, to date, neither an atomic quantum memory for non-classical states of light operating at a wavelength compatible with standard telecom fibre infrastructure, nor a fibre-based implementation of a quantum memory has been reported. Here we demonstrate the storage and faithful recall of the state of a 1532 nm wavelength photon, entangled with a 795 nm photon, in an ensemble of cryogenically cooled erbium ions doped into a 20 meter-long silicate fibre using a photon-echo quantum memory protocol. Despite its currently limited efficiency and storage time, our broadband light-matter interface brings fibre-based quantum networks one step closer to reality. Furthermore, it facilitates novel tests of light-matter interaction and collective atomic effects in unconventional materials.

  19. Precision Determination of Atmospheric Extinction at Optical and Near IR Wavelengths

    SciTech Connect (OSTI)

    Burke, David L.; /SLAC; Axelrod, T.; /Arizona U., Astron. Dept. - Steward Observ.; Blondin, Stephane; /European Southern Observ. /Marseille, CPPM; Claver, Chuck; /NOAO, Tucson; Ivezic, Zeljko; Jones, Lynne; /Washington U., Seattle, Astron. Dept.; Saha, Abhijit; /NOAO, Tucson; Smith, Allyn; /Austin Peay State U.; Smith, R.Chris; /Cerro-Tololo InterAmerican Obs.; Stubbs, Christopher W.; /Harvard-Smithsonian Ctr. Astrophys.

    2011-08-24T23:59:59.000Z

    The science goals for future ground-based all-sky surveys, such as the Dark Energy Survey, PanSTARRS, and the Large Synoptic Survey Telescope, require calibration of broadband photometry that is stable in time and uniform over the sky to precisions of a per cent or better, and absolute calibration of color measurements that are similarly accurate. This performance will need to be achieved with measurements made from multiple images taken over the course of many years, and these surveys will observe in less than ideal conditions. This paper describes a technique to implement a new strategy to directly measure variations of atmospheric transmittance at optical wavelengths and application of these measurements to calibration of ground-based observations. This strategy makes use of measurements of the spectra of a small catalog of bright 'probe' stars as they progress across the sky and back-light the atmosphere. The signatures of optical absorption by different atmospheric constituents are recognized in these spectra by their characteristic dependences on wavelength and airmass. State-of-the-art models of atmospheric radiation transport and modern codes are used to accurately compute atmospheric extinction over a wide range of observing conditions. We present results of an observing campaign that demonstrate that correction for extinction due to molecular constituents and aerosols can be done with precisions of a few millimagnitudes with this technique.

  20. Multi-wavelength variability properties of Fermi blazar S5 0716+714

    E-Print Network [OSTI]

    Liao, N H; Liu, H T; Weng, S S; Chen, Liang; Li, F

    2014-01-01T23:59:59.000Z

    S5 0716+714 is a typical BL Lacertae object. In this paper we present the analysis and results of long term simultaneous observations in the radio, near-infrared, optical, X-ray and $\\gamma$-ray bands, together with our own photometric observations for this source. The light curves show that the variability amplitudes in $\\gamma$-ray and optical bands are larger than those in the hard X-ray and radio bands and that the spectral energy distribution (SED) peaks move to shorter wavelengths when the source becomes brighter, which are similar to other blazars, i.e., more variable at wavelengths shorter than the SED peak frequencies. Analysis shows that the characteristic variability timescales in the 14.5 GHz, the optical, the X-ray, and the $\\gamma$-ray bands are comparable to each other. The variations of the hard X-ray and 14.5 GHz emissions are correlated with zero-lag, so are the V band and $\\gamma$-ray variations, which are consistent with the leptonic models. Coincidences of $\\gamma$-ray and optical flares ...

  1. Liquid-nitrogen cooled, free-running single-photon sensitive detector at telecommunication wavelengths

    E-Print Network [OSTI]

    M. Covi; B. Pressl; T. Günthner; K. Laiho; S. Krapick; C. Silberhorn; G. Weihs

    2015-02-10T23:59:59.000Z

    The measurement of light characteristics at the single- and few photon level plays a key role in many quantum optics applications. Often photodetection is preceded with the transmission of quantum light over long distances in optical fibers with their low loss window near 1550nm. Nonetheless, the detection of the photonic states at telecommunication wavelengths via avalanche photodetectors has long been facing severe restrictions. Only recently, demonstrations of the first free-running detector techniques in the telecommunication band have lifted the demand of synchronizing the signal with the detector. Moreover, moderate cooling is required to gain single-photon sensitivity with these detectors. Here we implement a liquid-nitrogen cooled negative-feedback avalanche diode (NFAD) at telecommunication wavelengths and investigate the properties of this highly flexible, free-running single-photon sensitive detector. Our realization of cooling provides a large range of stable operating temperatures and has advantages over the relatively bulky commercial refrigerators that have been used before. We determine the region of NFAD working parameters most suitable for single-photon sensitive detection enabling a direct plug-in of our detector to a true photon counting task.

  2. Multiple-wavelength spectroscopic quantitation of light-absorbing species in scattering media

    DOE Patents [OSTI]

    Nathel, Howard (Albany, CA); Cartland, Harry E. (Livermore, CA); Colston, Jr., Billy W. (Livermore, CA); Everett, Matthew J. (Pleasanton, CA); Roe, Jeffery N. (San Ramon, CA)

    2000-01-01T23:59:59.000Z

    An oxygen concentration measurement system for blood hemoglobin comprises a multiple-wavelength low-coherence optical light source that is coupled by single mode fibers through a splitter and combiner and focused on both a target tissue sample and a reference mirror. Reflections from both the reference mirror and from the depths of the target tissue sample are carried back and mixed to produce interference fringes in the splitter and combiner. The reference mirror is set such that the distance traversed in the reference path is the same as the distance traversed into and back from the target tissue sample at some depth in the sample that will provide light attenuation information that is dependent on the oxygen in blood hemoglobin in the target tissue sample. Two wavelengths of light are used to obtain concentrations. The method can be used to measure total hemoglobin concentration [Hb.sub.deoxy +Hb.sub.oxy ] or total blood volume in tissue and in conjunction with oxygen saturation measurements from pulse oximetry can be used to absolutely quantify oxyhemoglobin [HbO.sub.2 ] in tissue. The apparatus and method provide a general means for absolute quantitation of an absorber dispersed in a highly scattering medium.

  3. Light response of pure CsI calorimeter crystals painted with wavelength-shifting lacquer

    E-Print Network [OSTI]

    E. Frlez; Ch. Broennimann; B. Krause; D. Pocanic; D. Renker; S. Ritt; P. L. Slocum; I. Supek; H. P. Wirtz

    2000-06-21T23:59:59.000Z

    We have measured scintillation properties of pure CsI crystals used in the shower calorimeter built for a precise determination of the pi+ -> pi0 e+ nu decay rate at the Paul Scherrer Institute (PSI). All 240 individual crystals painted with a special wavelength-shifting solution were examined in a custom-build detection apparatus (RASTA=radioactive source tomography apparatus) that uses a 137Cs radioactive gamma source, cosmic muons and a light emitting diode as complementary probes of the scintillator light response. We have extracted the total light output, axial light collection nonuniformities and timing responses of the individual CsI crystals. These results predict improved performance of the 3 pi sr PIBETA calorimeter due to the painted lateral surfaces of 240 CsI crystals. The wavelength-shifting paint treatment did not affect appreciably the total light output and timing resolution of our crystal sample. The predicted energy resolution for positrons and photons in the energy range of 10-100 MeV was nevertheless improved due to the more favorable axial light collection probability variation. We have compared simulated calorimeter ADC spectra due to 70 MeV positrons and photons with a Monte Carlo calculation of an ideal detector light response.

  4. Towards Understanding Stellar Radial Velocity Jitter as a Function of Wavelength: The Sun as a Proxy

    E-Print Network [OSTI]

    Marchwinski, Robert C; Robertson, Paul; Ramsey, Lawrence; Harder, Jerald

    2014-01-01T23:59:59.000Z

    Using solar spectral irradiance measurements from the SORCE spacecraft and the F/F' technique, we have estimated the radial velocity (RV) scatter induced on the Sun by stellar activity as a function of wavelength. Our goal was to evaluate the potential advantages of using new near-infrared (NIR) spectrographs to search for low-mass planets around bright F, G, and K stars by beating down activity effects. Unlike M dwarfs, which have higher fluxes and therefore greater RV information content in the NIR, solar-type stars are brightest at visible wavelengths, and, based solely on information content, are better suited to traditional optical RV surveys. However, we find that the F/F' estimated RV noise induced by stellar activity is diminished by up to a factor of 4 in the NIR versus the visible. Observations with the upcoming future generation of NIR instruments can be a valuable addition to the search for low-mass planets around bright FGK stars in reducing the amount of stellar noise affecting RV measurements.

  5. Raman Scattering at Plasmonic Junctions Shorted by Conductive...

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

    between line spectra and band spectra, can be assigned to shorting the junction plasmon through molecular conductive bridges. This is demonstrated through Raman trajectories...

  6. Development and Deployment of a Short Rotation Woody Crops Harvesting...

    Office of Scientific and Technical Information (OSTI)

    SRC Woody Crop Header Re-direct Destination: Demand for bioenergy sourced from woody biomass is projected to increase; however, the expansion and rapid deployment of short...

  7. Short-term energy outlook. Quarterly projections, Third quarter 1994

    SciTech Connect (OSTI)

    Not Available

    1994-08-02T23:59:59.000Z

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent cases with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202). The feature article for this issue is Demand, Supply and Price Outlook for Reformulated Gasoline, 1995.

  8. Short Paper: PEPSI: Privacy-Enhanced Participatory Sensing Infrastructure

    E-Print Network [OSTI]

    Politécnica de Madrid, Universidad

    Short Paper: PEPSI: Privacy-Enhanced Participatory Sensing Infrastructure Emiliano De Cristofaro-secure guarantees. In this paper, we introduce PEPSI: Privacy- Enhanced Participatory Sensing Infrastructure. We

  9. Smooth Field Theories and Homotopy Field Theories

    E-Print Network [OSTI]

    Wilder, Alan Cameron

    2011-01-01T23:59:59.000Z

    1 . . . . . . . . 4 Categories of Field Theories 4.1 Functorto super symmetric field theories. CRM Proceedings and0-dimensional super symmetric field theories. preprint 2008.

  10. New analysis of the common nuclear dependence of the EMC effect and short-range correlations

    E-Print Network [OSTI]

    Fomin, Nadia

    2012-01-01T23:59:59.000Z

    The strong repulsive core of the nucleon-nucleon (NN) interaction at short distances prevents nucleons from becoming close to each other. This gives rise to high-momentum nucleons in the nucleus that cannot be explained in the context of the mean field and are commonly called short-range correlations (SRCs). They are responsible for the strength seen in momentum distribution tails seen in all nuclei, and we can obtain a relative measure of SRCs via cross section ratios to light nuclei. Recent inclusive scattering data from Jefferson Lab have allowed a precise determination of the A-dependence of SRCs in nuclei and suggests that, like the EMC effect, it is especially sensitive to the nuclear local density. These new results, as well as a new analysis of the relationship between SRCs and the EMC effect, will be presented and discussed.

  11. New analysis of the common nuclear dependence of the EMC effect and short-range correlations

    E-Print Network [OSTI]

    Nadia Fomin

    2012-09-07T23:59:59.000Z

    The strong repulsive core of the nucleon-nucleon (NN) interaction at short distances prevents nucleons from becoming close to each other. This gives rise to high-momentum nucleons in the nucleus that cannot be explained in the context of the mean field and are commonly called short-range correlations (SRCs). They are responsible for the strength seen in momentum distribution tails seen in all nuclei, and we can obtain a relative measure of SRCs via cross section ratios to light nuclei. Recent inclusive scattering data from Jefferson Lab have allowed a precise determination of the A-dependence of SRCs in nuclei and suggests that, like the EMC effect, it is especially sensitive to the nuclear local density. These new results, as well as a new analysis of the relationship between SRCs and the EMC effect, will be presented and discussed.

  12. Short-term Variations in the Galactic Environment of the Sun

    E-Print Network [OSTI]

    Priscilla C. Frisch; Jonathan D. Slavin

    2006-01-17T23:59:59.000Z

    The galactic environment of the Sun varies over short timescales as the Sun and interstellar clouds travel through space. Small variations in the dynamics, ionization, density, and magnetic field strength of the interstellar medium (ISM) surrounding the Sun yield pronounced changes in the heliosphere. We discuss essential information required to understand short-term variations in the galactic environment of the Sun, including the distribution and radiative transfer properties of nearby ISM, and variations in the boundary conditions of the heliosphere as the Sun traverses clouds. The most predictable transitions are when the Sun emerged from the Local Bubble interior and entered the cluster of local interstellar clouds flowing past the Sun, within the past 140,000 years, and again when the Sun entered the local interstellar cloud now surrounding and inside of the solar system, sometime during the past 44,000 years.

  13. The X-ray afterglow flat segment in short GRB 051221A: Energy injection from a millisecond magnetar?

    E-Print Network [OSTI]

    Yizhong Fan; Dong Xu

    2006-07-12T23:59:59.000Z

    The flat segment lasting $\\sim 10^4$ seconds in the X-ray afterglow of GRB051221A represents the first clear case of strong energy injection in the external shock of a short GRB afterglow. In this work, we show that a millisecond pulsar with dipole magnetic field $\\sim 10^{14}$ Gauss could well account for that energy injection. The good quality X-ray flat segment thus suggests that the central engine of this short burst may be a millisecond magnetar.

  14. SUNY Programs: Semester, Academic Year and Short Term

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    SUNY Programs: Italy Semester, Academic Year and Short Term #12;1 Table of Contents How to Use This Booklet 1 A Brief Overview 2 Semester and Academic Year Programs 3 Short Term Programs 8 Contact of programs offered in Italy by SUNY campuses. These listings provide a summary about the basic

  15. SUNY Programs: Semester, Academic Year and Short Term

    E-Print Network [OSTI]

    Suzuki, Masatsugu

    SUNY Programs: France Semester, Academic Year and Short Term #12;1 Table of Contents How to Use This Booklet 1 A Brief Overview 2 Semester and Academic Year Programs 3 Short Term Programs 6 SUNY Programs in Canada and other Francophone Locations 9 Recommended non-SUNY Program 11 Contact Information for all SUNY

  16. Short-term energy outlook, annual supplement 1994

    SciTech Connect (OSTI)

    Not Available

    1994-08-01T23:59:59.000Z

    The Short-Term Energy Outlook Annual Supplement (Supplement) is published once a year as a complement to the Short-Term Energy Outlook (Outlook), Quarterly Projections. The purpose of the Supplement is to review the accuracy of the forecasts published in the Outlook, make comparisons with other independent energy forecasts, and examine current energy topics that affect the forecasts.

  17. Short-term energy outlook annual supplement, 1993

    SciTech Connect (OSTI)

    NONE

    1993-08-06T23:59:59.000Z

    The Short-Term Energy Outlook Annual Supplement (supplement) is published once a year as a complement to the Short-Term Energy Outlook (Outlook), Quarterly Projections. The purpose of the Supplement is to review the accuracy of the forecasts published in the Outlook, make comparisons with other independent energy forecasts, and examine current energy topics that affect the forecasts.

  18. ORIGINAL CONTRIBUTION Ozone and Short-term Mortality

    E-Print Network [OSTI]

    Dominici, Francesca

    ORIGINAL CONTRIBUTION Ozone and Short-term Mortality in 95 US Urban Communities, 1987-2000 MichelleD E XPOSURE TO TROPOSPHERIC OZONE is widespread in the United States,1,2 occurring also outside southernCalifornia,whereozone formation was first recognized.3 Short- term exposure to ozone has been

  19. Mutually injecting semiconductor lasers: simulations for short and zero delay

    E-Print Network [OSTI]

    Wünsche, Hans-Jürgen "Ede"

    Mutually injecting semiconductor lasers: simulations for short and zero delay Nikolay Korneyev a und Stochastik, Mohrenstr. 39, 10117 Berlin, Germany ABSTRACT Distant lasers with mutual optical the relaxation oscillation period. In order to illuminate the role of these short delays, the ultimate zero

  20. ROBERT B. SHORT SCHOLARSHIP IN ZOOLOGY Department of Biological Science

    E-Print Network [OSTI]

    Ronquist, Fredrik

    The Robert B. Short Scholarship in Zoology provides an award of up to $1,000 to a currently enrolled graduateROBERT B. SHORT SCHOLARSHIP IN ZOOLOGY Department of Biological Science Florida State University of the proposed off-campus experience to the applicant's biological and career interests. ELIGIBILITY Currently

  1. Journal of Power Sources 153 (2006) 345349 Short communication

    E-Print Network [OSTI]

    Cho, Jaephil

    2006-01-01T23:59:59.000Z

    fire as a result of an internal short circuit. Therefore, the guidelines recommend that a cellJournal of Power Sources 153 (2006) 345­349 Short communication Improvement of 12 V overcharge that block the high temperature, high current, overcharging and a have safety pressure-release rupture vent

  2. Type Inference Builds a Short Cut to Deforestation Olaf Chitil

    E-Print Network [OSTI]

    Kent, University of

    Type Inference Builds a Short Cut to Deforestation Olaf Chitil Lehrstuhl f¨ur Informatik II, RWTH Aachen, 52056 Aachen, Germany chitil@informatik.rwth-aachen.de Abstract Deforestation optimises structures. Short cut deforestation is a de- forestation method which is based on a single, local trans

  3. Optimal Short-Range Routing of Vessels in a Seaway

    E-Print Network [OSTI]

    Smith, Robert L.

    Optimal Short-Range Routing of Vessels in a Seaway Irina S. Dolinskaya¹ Miltiadis Kotinis² Michael Industrial and Operations Engineering 1205 Beal Avenue Ann Arbor, Michigan 48109 ²Old Dominion University Short-Range Routing of Vessels in a Seaway Dolinskaya, I. S.1 , Kotinis, M.2 , Parsons, M. G.3

  4. Short-Circuit Modeling of a Wind Power Plant: Preprint

    SciTech Connect (OSTI)

    Muljadi, E.; Gevorgian, V.

    2011-03-01T23:59:59.000Z

    This paper investigates the short-circuit behavior of a WPP for different types of wind turbines. The short-circuit behavior will be presented. Both the simplified models and detailed models are used in the simulations and both symmetrical faults and unsymmetrical faults are discussed.

  5. Entomology 489 Field Entomology Field Project Guide

    E-Print Network [OSTI]

    Behmer, Spencer T.

    with information, people, materials). Field Projects (your project should...) FEntomology 489 ­ Field Entomology Field Project Guide A small-group field project is required for ENTO 489 ­ Field Entomology. This guide provides general information about the field-project

  6. Propagation of ultra-short solitons in stochastic Maxwell's equations

    SciTech Connect (OSTI)

    Kurt, Levent, E-mail: LKurt@gc.cuny.edu [Department of Science, Borough of Manhattan Community College, City University of New York, New York, New York 10007 (United States)] [Department of Science, Borough of Manhattan Community College, City University of New York, New York, New York 10007 (United States); Schäfer, Tobias [Department of Mathematics, College of Staten Island, City University of New York, Staten Island, New York 10314 (United States)] [Department of Mathematics, College of Staten Island, City University of New York, Staten Island, New York 10314 (United States)

    2014-01-15T23:59:59.000Z

    We study the propagation of ultra-short short solitons in a cubic nonlinear medium modeled by nonlinear Maxwell's equations with stochastic variations of media. We consider three cases: variations of (a) the dispersion, (b) the phase velocity, (c) the nonlinear coefficient. Using a modified multi-scale expansion for stochastic systems, we derive new stochastic generalizations of the short pulse equation that approximate the solutions of stochastic nonlinear Maxwell's equations. Numerical simulations show that soliton solutions of the short pulse equation propagate stably in stochastic nonlinear Maxwell's equations and that the generalized stochastic short pulse equations approximate the solutions to the stochastic Maxwell's equations over the distances under consideration. This holds for both a pathwise comparison of the stochastic equations as well as for a comparison of the resulting probability densities.

  7. Integrated switch for simultaneous mode-division multiplexing (MDM) and wavelength-division multiplexing (WDM)

    E-Print Network [OSTI]

    Stern, Brian; Chen, Christine P; Tzuang, Lawrence D; Cardenas, Jaime; Bergman, Keren; Lipson, Michal

    2015-01-01T23:59:59.000Z

    Leveraging the spatial modes of multimode waveguides using mode-division multiplexing (MDM) on an integrated photonic chip allows unprecedented scaling of bandwidth density for on-chip communication. Switching channels between waveguides is critical for future scalable optical networks, but its implementation in multimode waveguides must address how to simultaneously control modes with vastly different optical properties. Here we present a platform for switching signals between multimode waveguides based on individually processing the spatial mode channels using single-mode elements. Using this wavelength-division multiplexing (WDM) compatible platform, we demonstrate a 1x2 multimode switch for a silicon chip which routes four data channels with low (power penalties below 1.4 dB on all channels while routing 10 Gbps data when each channel is input and routed separately. The switch exhibits an additional power penalty of less than 2.4 dB when all f...

  8. Achieving selective interrogation and sub-wavelength resolution in thin plates with embedded metamaterial acoustic lenses

    SciTech Connect (OSTI)

    Semperlotti, F., E-mail: fsemperl@nd.edu; Zhu, H. [Department of Aerospace and Mechanical Engineering, University of Notre Dame, Notre Dame, Indiana 46556 (United States)

    2014-08-07T23:59:59.000Z

    In this study, we present an approach to ultrasonic beam-forming and high resolution identification of acoustic sources having critical implications for applications such as structural health monitoring. The proposed concept is based on the design of dynamically tailored structural elements via embedded acoustic metamaterial lenses. This approach provides a completely new alternative to conventional phased-array technology enabling the formation of steerable and collimated (or focused) ultrasonic beams by exploiting a single transducer. Numerical results show that the ultrasonic beam can be steered by simply tuning the frequency of the excitation. Also, the embedded lens can be designed to achieve sub-wavelength resolution to clustered acoustic sources, which is a typical scenario encountered in incipient structural damage.

  9. First Lasing of Volume FEL (VFEL) at Wavelength Range $?\\sim $ 4-6 mm

    E-Print Network [OSTI]

    V. Baryshevsky; K. Batrakov; A. Gurinovich; I. Ilienko; A. Lobko; V. Moroz; P. Sofronov; V. Stolyarsky

    2001-07-18T23:59:59.000Z

    First lasing of volume free electron laser (VFEL) is described. The generating system consists of two metal diffraction grating with different spatial periods. The first grating creates the conditions for Smith Purcell emission mechanism. The second grating provides the distributed feedback for emitted wave. The length of diffraction grating is 10 cm. Electron beam pulse with a time duration $\\tau \\sim$ 10 ms has a sinusoidal form with the amplitude varied from 1 to ~10 kV. The measured microwave power reached the value of about 3-4 W in mm wavelength range. The generation stops at threshold current value. When the current tends to the threshold value, the region of generation tends to a narrow band near to 5 kV. At higher current values the radiation appears in electron energy range 5 - 7.5 KeV.

  10. Multi-wavelength differential astrometry of the S5 polar cap sample

    E-Print Network [OSTI]

    J. C. Guirado; J. M. Marcaide; E. Ros; M. A. Perez-Torres; I. Marti-Vidal

    2004-12-17T23:59:59.000Z

    We report on the status of our S5 polar cap astrometry program. Since 1997 we have observed all the 13 radio sources of the complete S5 polar cap sample at the wavelengths of 3.6 cm, 2 cm and 7 mm. Images of the radio sources at 3.6 and 2 cm have already been published reporting morphological changes. Preliminary astrometric analyses have been carried out at three frequencies with precisions in the relative position determination ranging from 80 to 20 microarcseconds. We report also on the combination of our phase-delay global astrometry results with the microarcsecond-precise optical astrometry that will be provided by future space-based instruments.

  11. Method and device for predicting wavelength dependent radiation influences in thermal systems

    DOE Patents [OSTI]

    Kee, Robert J. (864 Lucille St., Livermore, CA 94550); Ting, Aili (7329 Stonedale Dr., Pleasanton, CA 94558)

    1996-01-01T23:59:59.000Z

    A method and apparatus for predicting the spectral (wavelength-dependent) radiation transport in thermal systems including interaction by the radiation with partially transmitting medium. The predicted model of the thermal system is used to design and control the thermal system. The predictions are well suited to be implemented in design and control of rapid thermal processing (RTP) reactors. The method involves generating a spectral thermal radiation transport model of an RTP reactor. The method also involves specifying a desired wafer time dependent temperature profile. The method further involves calculating an inverse of the generated model using the desired wafer time dependent temperature to determine heating element parameters required to produce the desired profile. The method also involves controlling the heating elements of the RTP reactor in accordance with the heating element parameters to heat the wafer in accordance with the desired profile.

  12. Fabrication of Ceramic Layer-by-Layer Infrared Wavelength Photonic Band Gap Crystals

    SciTech Connect (OSTI)

    Henry Hao-Chuan Kang

    2004-12-19T23:59:59.000Z

    Photonic band gap (PBG) crystals, also known as photonic crystals, are periodic dielectric structures which form a photonic band gap that prohibit the propagation of electromagnetic (EM) waves of certain frequencies at any incident angles. Photonic crystals have several potential applications including zero-threshold semiconductor lasers, the inhibition of spontaneous emission, dielectric mirrors, and wavelength filters. If defect states are introduced in the crystals, light can be guided from one location to another or even a sharp bending of light in micron scale can be achieved. This generates the potential for optical waveguide and optical circuits, which will contribute to the improvement in the fiber-optic communications and the development of high-speed computers.

  13. Multi-wavelength Raman scattering of nanostructured Al-doped zinc oxide

    SciTech Connect (OSTI)

    Russo, V.; Ghidelli, M.; Gondoni, P. [Dipartimento di Energia and NEMAS, Center for Nanoengineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, I-20133 Milano (Italy); Casari, C. S.; Li Bassi, A. [Dipartimento di Energia and NEMAS, Center for Nanoengineered Materials and Surfaces, Politecnico di Milano, via Ponzio 34/3, I-20133 Milano (Italy); Center for Nano Science and Technology PoliMI, Istituto Italiano di Tecnologia, Via Pascoli 70/3, I-20133 Milano (Italy)

    2014-02-21T23:59:59.000Z

    In this work we present a detailed Raman scattering investigation of zinc oxide and aluminum-doped zinc oxide (AZO) films characterized by a variety of nanoscale structures and morphologies and synthesized by pulsed laser deposition under different oxygen pressure conditions. The comparison of Raman spectra for pure ZnO and AZO films with similar morphology at the nano/mesoscale allows to investigate the relation between Raman features (peak or band positions, width, relative intensity) and material properties such as local structural order, stoichiometry, and doping. Moreover Raman measurements with three different excitation lines (532, 457, and 325?nm) point out a strong correlation between vibrational and electronic properties. This observation confirms the relevance of a multi-wavelength Raman investigation to obtain a complete structural characterization of advanced doped oxide materials.

  14. Long-Lasting Black-Hole Jets in Short Gamma-Ray Bursts

    E-Print Network [OSTI]

    Kisaka, Shota

    2015-01-01T23:59:59.000Z

    Whether a short gamma-ray burst (GRB) is caused by a black hole (BH) or a neutron star (NS) after the merger of a NS binary is a crucial problem. We propose a BH model that explains short GRBs with long-lasting activities such as extended emission and plateau emission up to $\\sim10000$ s. To extract the BH rotational energy, the topological evolution of the magnetic field should accompany the mass ejection, mass fallback, and magnetic field reconnection. The observations suggest the magnetic field decay from $\\sim10^{14}$ G to $\\sim10^{13} - 10^{11}$ G at the BH, bounded below by the pre-merger strength and kept constant while the luminosity is constant, and the fallback mass of $\\sim10^{-4} - 10^{-2} M_{\\odot}$, comparable to the ejecta mass implied by the macronova in GRB 130603B. The BH model has implications for gravitational waves and the equation of state of NS matter.

  15. Resonant third-harmonic generation of a short-pulse laser from electron-hole plasmas

    SciTech Connect (OSTI)

    Kant, Niti [Department of Physics, Lovely Professional University, Phagwara, Punjab 144 402 (India); Nandan Gupta, Devki [Department of Physics and Astrophysics, University of Delhi, Delhi 110 007 (India); Suk, Hyyong [Advanced Photonics Research Institute (APRI) and Graduate Program of Photonics and Applied Physics, Gwangju Institute of Science and Technology, Gwangju 500 712 (Korea, Republic of)

    2012-01-15T23:59:59.000Z

    In semiconductors, free carriers are created in pairs in inter-band transitions and consist of an electron and its corresponding hole. At very high carrier densities, carrier-carrier collisions dominate over carrier-lattice collisions and carriers begin to behave collectively to form plasma. Here, we apply a short-pulse laser to generate third-harmonic radiation from a semiconductor plasma (electron-hole plasma) in the presence of a transverse wiggler magnetic-field. The process of third-harmonic generation of an intense short-pulse laser is resonantly enhanced by the magnetic wiggler, i.e., wiggler magnetic field provides the necessary momentum to third-harmonic photons. In addition, a high-power laser radiation, propagating through a semiconductor imparts an oscillatory velocity to the electrons and exerts a ponderomotive force on electrons at the third-harmonic frequency of the laser. This oscillatory velocity produces a third-harmonic longitudinal current. And due to the beating of the longitudinal electron velocity and the wiggler magnetic field, a transverse third-harmonic current is produced that drives third-harmonic electromagnetic radiation. It is finally observed that for a specific wiggler wave number value, the phase-matching conditions for the process are satisfied, leading to resonant enhancement in the energy conversion efficiency.

  16. Monolithic phosphor-free InGaN/GaN quantum dot wavelength converter white light emitting diodes

    SciTech Connect (OSTI)

    Jahangir, Shafat; Bhattacharya, Pallab, E-mail: pkb@eecs.umich.edu [Center for Photonics and Multiscale Nanomaterials, Department of Electrical Engineering and Computer Science, University of Michigan, Ann Arbor, Michigan 48109-2122 (United States); Pietzonka, Ines; Strassburg, Martin [OSRAM Opto Semiconductors GmbH, Leibnizstrasse 4, Regensburg (Germany)

    2014-09-15T23:59:59.000Z

    We report the characteristics of phosphor-free self-organized InGaN/GaN quantum dot wavelength converter white light emitting diodes grown by plasma assisted molecular beam epitaxy. The exciting quantum dots, in which electrically injected carriers recombine, are blue-emitting and the converter dots are red-emitting. We have studied the effect of tuning the number of dot layers and the peak emission wavelength of the exciting and converter dots on the nature of the emitted white light, in terms of the chromaticity coordinates and correlated color temperature. Depending on the values of these wavelengths, color temperatures in the range of 4420–6700?K have been derived at a current density of 45?A/cm{sup 2} across multiple devices. The variation of the color temperature with change in injection current is found to be very small.

  17. Observation of a Long-Wavelength Hosing Modulation of a High-Intensity Laser Pulse in Underdense Plasma

    E-Print Network [OSTI]

    Kaluza, M C; Thomas, A G R; Najmudin, Z; Dangor, A E; Murphy, C D; Collier, J L; Divall, E J; Foster, P S; Hooker, C J; Langley, A J; Smith, J; Krushelnick, K

    2010-01-01T23:59:59.000Z

    We report the first experimental observation of a long-wavelength hosing modulation of a high-intensity laser pulse. Side-view images of the scattered optical radiation at the fundamental wave-length of the laser reveal a transverse oscillation of the laser pulse during its propagation through underdense plasma. The wavelength of the oscillation \\lambda_hosing depends on the background plasma density n_e and scales as \\lambda_hosing~n_e^-3/2. Comparisons with an analytical model and 2-dimensional particle-in-cell simulations reveal that this laser hosing can be induced by a spatio-temporal asymmetry of the intensity distribution in the laser focus which can be caused by a misalignment of the parabolic focussing mirror or of the diffraction gratings in the pulse compressor.

  18. A short model excitation of an asymmetric force free superconducting transmission line magnet

    SciTech Connect (OSTI)

    Wake, M.; Sato, H.; /KEK, Tsukuba; Carcagno, R.; Foster, W.; Hays, S.; Kashikhin, V.; Oleck, A.; Piekarz, H.; Rabehl, R,; /Fermilab

    2005-09-01T23:59:59.000Z

    A short model of asymmetric force free magnet with single beam aperture was tested at Fermilab together with the excitation test of VLHC transmission line magnet. The design concept of asymmetric force free superconducting magnet was verified by the test. The testing reached up to 104 kA current and no indication of force imbalance was observed. Since the model magnet length was only 10cm, A 0.75m model was constructed and tested at KEK with low current to ensure the validity of the design. The cool down and the excitation at KEK were also successful finding very small thermal contraction of the conductor and reasonable field homogeneity.

  19. Short Range Correlations in Nuclei at Large xbj through Inclusive Quasi-Elastic Electron Scattering

    SciTech Connect (OSTI)

    Ye, Zhihong [UVA

    2013-12-01T23:59:59.000Z

    The experiment, E08-014, in Hall-A at Jefferson Lab aims to study the short-range correlations (SRC) which are necessary to explain the nuclear strength absent in the mean field theory. The cross sections for 2H, 3He, 4He, 12C, 40Ca and 48Ca, were measured via inclusive quasi-elastic electron scattering from these nuclei in a Q2 range between 0.8 and 2.8 (GeV/c)^2 for x>1. The cross section ratios of heavy nuclei to 2H were extracted to study two-nucleon SRC for 1

  20. Quantum statistics effect in Schwinger pair production in short laser pulses

    E-Print Network [OSTI]

    Florian Hebenstreit; Reinhard Alkofer; Gerald V. Dunne; Holger Gies

    2009-10-23T23:59:59.000Z

    We investigate non-perturbative pair production from vacuum (the Schwinger effect) in the focal region of two counter-propagating, ultra-short laser pulses with sub-cycle structure. We use the quantum kinetic formulation to calculate the momentum spectrum of created particles and show the extreme sensitivity to the laser frequency $\\omega$, the pulse length $\\tau$ and the carrier-envelope absolute phase $\\phi$. We apply this formalism to both fermions and bosons to illustrate the influence of quantum statistics in this type of electric background field.

  1. Plasmonic Meta-Surface for Efficient Ultra-Short Pulse Laser-Driven Particle Acceleration

    E-Print Network [OSTI]

    Bar-Lev, Doron

    2014-01-01T23:59:59.000Z

    A laser-driven particle accelerator based on plasmonic nano-antennas is proposed and analyzed. The concept utilizes the enhancement and localization of the electric field by nano-antennas to maximize the acceleration gradient and to overcome potential metallic losses. The structure is optimized for accelerating relativistic particles using a femto-second laser source operating at 800nm, and is shown to support the bandwidth of ultra-short laser pulses (up to 16fsec) while providing a high acceleration gradient potentially reaching 11.6GV/m.

  2. The Millisecond Magnetar Central Engine in short GRBs

    E-Print Network [OSTI]

    Lü, Hou-Jun; Lei, Wei-Hua; Li, Ye; Lasky, Paul D

    2015-01-01T23:59:59.000Z

    One favored progenitor model for short duration gamma-ray bursts (SGRBs) is the coalescence of two neutron stars (NS-NS). One possible outcome of such a merger would be a rapidly spinning, strongly magnetized neutron star (known as a millisecond magnetar). These magnetars may be "supra-massive", implying they would collapse to black holes after losing centrifugal support due to magnetic dipole spindown. By systematically analyzing the BAT-XRT light curves of all short GRBs detected by {\\em swift}, we test how well the data are consistent with this central engine model of short GRBs. We find that the so-called "extended emission" observed with BAT in some short GRBs are fundamentally the same component as the "internal X-ray plateau" as observed in many short GRBs, which is defined as a plateau in the lightcurve followed by a very rapid drop. Based on how likely a short GRB hosts a magnetar, we characterize the entire {\\em Swift} short GRB sample into three categories: the "internal plateau" sample, the "exter...

  3. PLANETARY AND OTHER SHORT BINARY MICROLENSING EVENTS FROM THE MOA SHORT-EVENT ANALYSIS

    SciTech Connect (OSTI)

    Bennett, D. P. [Department of Physics, University of Notre Dame, Notre Dame, IN 46556 (United States); Sumi, T. [Department of Earth and Space Science, Osaka University, Osaka 560-0043 (Japan); Bond, I. A.; Ling, C. H. [Institute for Information and Mathematical Sciences, Massey University, Auckland 1330 (New Zealand); Kamiya, K.; Abe, F.; Fukui, A.; Furusawa, K.; Itow, Y.; Masuda, K.; Matsubara, Y.; Miyake, N.; Muraki, Y. [Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya 464-8601 (Japan); Botzler, C. S.; Rattenbury, N. J. [Department of Physics, University of Auckland, Private Bag 92-019, Auckland 1001 (New Zealand); Korpela, A. V.; Sullivan, D. J. [School of Chemical and Physical Sciences, Victoria University, Wellington (New Zealand); Kilmartin, P. M. [Mt. John Observatory, P.O. Box 56, Lake Tekapo 8770 (New Zealand); Ohnishi, K. [Nagano National College of Technology, Nagano 381-8550 (Japan); Saito, To., E-mail: bennett@nd.edu [Tokyo Metropolitan College of Aeronautics, Tokyo 116-8523 (Japan); Collaboration: MOA Collaboration; and others

    2012-10-01T23:59:59.000Z

    We present the analysis of four candidate short-duration binary microlensing events from the 2006-2007 MOA Project short-event analysis. These events were discovered as a by-product of an analysis designed to find short-timescale single-lens events that may be due to free-floating planets. Three of these events are determined to be microlensing events, while the fourth is most likely caused by stellar variability. For each of the three microlensing events, the signal is almost entirely due to a brief caustic feature with little or no lensing attributable mainly to the lens primary. One of these events, MOA-bin-1, is due to a planet, and it is the first example of a planetary event in which the stellar host is only detected through binary microlensing effects. The mass ratio and separation are q (4.9 {+-} 1.4) Multiplication-Sign 10{sup -3} and s = 2.10 {+-} 0.05, respectively. A Bayesian analysis based on a standard Galactic model indicates that the planet, MOA-bin-1Lb, has a mass of m{sub p} = 3.7 {+-} 2.1 M{sub Jup} and orbits a star of M{sub *} = 0.75{sub -0.41}{sup +}0{sup .33} M{sub Sun} at a semimajor axis of a = 8.3{sub -2.7}{sup +4.5} AU. This is one of the most massive and widest separation planets found by microlensing. The scarcity of such wide-separation planets also has implications for interpretation of the isolated planetary mass objects found by this analysis. If we assume that we have been able to detect wide-separation planets with an efficiency at least as high as that for isolated planets, then we can set limits on the distribution of planets in wide orbits. In particular, if the entire isolated planet sample found by Sumi et al. consists of planets bound in wide orbits around stars, we find that it is likely that the median orbital semimajor axis is >30 AU.

  4. On Field Constraint Analysis

    E-Print Network [OSTI]

    Wies, Thomas

    2005-11-03T23:59:59.000Z

    We introduce field constraint analysis, a new technique for verifying data structure invariants. A field constraint for a field is a formula specifying a set of objects to which the field can point. Field constraints ...

  5. Short-term energy outlook. Quarterly projections, Third quarter 1995

    SciTech Connect (OSTI)

    NONE

    1995-08-02T23:59:59.000Z

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent projections with those of other forecasting services, and discusses current topics related to the short-term energy markets. The forecast period for this issue of the Outlook extends from the third quarter of 1995 through the fourth quarter of 1996. Values for the second quarter of 1995, however, are preliminary EIA estimates.

  6. INTERPLANETARY NETWORK LOCALIZATIONS OF KONUS SHORT GAMMA-RAY BURSTS

    SciTech Connect (OSTI)

    Pal'shin, V. D.; Svinkin, D. S.; Aptekar, R. L.; Golenetskii, S. V.; Frederiks, D. D.; Mazets, E. P.; Oleynik, P. P.; Ulanov, M. V. [Ioffe Physical Technical Institute, St. Petersburg, 194021 (Russian Federation); Hurley, K. [Space Sciences Laboratory, University of California, 7 Gauss Way, Berkeley, CA 94720-7450 (United States); Cline, T.; Trombka, J.; McClanahan, T. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Mitrofanov, I. G.; Golovin, D. V.; Kozyrev, A. S.; Litvak, M. L.; Sanin, A. B. [Space Research Institute, 84/32, Profsoyuznaya, Moscow 117997 (Russian Federation); Boynton, W.; Fellows, C.; Harshman, K., E-mail: val@mail.ioffe.ru [Department of Planetary Sciences, University of Arizona, Tucson, AZ 85721 (United States); and others

    2013-08-15T23:59:59.000Z

    Between the launch of the Global Geospace Science Wind spacecraft in 1994 November and the end of 2010, the Konus-Wind experiment detected 296 short-duration gamma-ray bursts (including 23 bursts which can be classified as short bursts with extended emission). During this period, the Interplanetary Network (IPN) consisted of up to 11 spacecraft, and using triangulation, the localizations of 271 bursts were obtained. We present the most comprehensive IPN localization data on these events. The short burst detection rate, {approx}18 yr{sup -1}, exceeds that of many individual experiments.

  7. Exact theory and numeric results for short pulse ionization of simple model atom in one dimension

    E-Print Network [OSTI]

    Rokhlenko, Alexander

    2015-01-01T23:59:59.000Z

    Our exact theory for continuous harmonic perturbation of a one dimensional model atom by parametric variations of its potential is generalized for the cases when a) the atom is exposed to short pulses of an external harmonic electric field and b) the forcing is represented by short bursts of different shape changing the strength of the binding potential. This work is motivated not only by the wide use of laser pulses for atomic ionization, but also by our earlier study of the same model which successfully described the ionization dynamics in all orders, i.e. the multi-photon processes, though being treated by the non-relativistic Schr\\"odinger equation. In particular, it was shown that the bound atom cannot survive the excitation of its potential caused by any non-zero frequency and amplitude of the continuous harmonic forcing. Our present analysis found important laws of the atomic ionization by short pulses, in particular the efficiency of ionizing this model system and presumably real ones as well.

  8. Coherent nonlinear propagation of ultrafast electric field transients through intersubband resonances

    E-Print Network [OSTI]

    Purdue University

    of intersubband excitations is demonstrated by applying two phase-locked pulses with variable relative phase 2001 Amplitude and phase-controlled midinfrared field transients at a wavelength of 12.5 m induce resonant intersubband excitations in n-type modulation-doped GaAs/AlGaAs quantum wells. The transmitted

  9. Potential Science for the OASIS Integral Field Spectrograph with Laser Guide Star Adaptive Optics

    E-Print Network [OSTI]

    Morris, S L; Swinbank, M; Wilman, R

    2006-01-01T23:59:59.000Z

    We review the science case for the Laser Guide Star system being built for the William Herschel Telescope (WHT) on La Palma. When used in combination with the NAOMI Adaptive Optics system and the OASIS visible-wavelength Integral Field Spectrograph, we demonstrate that there are substantial, exciting areas of astrophysical research in which the WHT can contribute.

  10. Potential Science for the OASIS Integral Field Spectrograph with Laser Guide Star Adaptive Optics

    E-Print Network [OSTI]

    S. L. Morris; J. Gerssen; M. Swinbank; R. Wilman

    2005-09-15T23:59:59.000Z

    We review the science case for the Laser Guide Star system being built for the William Herschel Telescope (WHT) on La Palma. When used in combination with the NAOMI Adaptive Optics system and the OASIS visible-wavelength Integral Field Spectrograph, we demonstrate that there are substantial, exciting areas of astrophysical research in which the WHT can contribute.

  11. Quantum field theory in spaces with closed timelike curves

    SciTech Connect (OSTI)

    Boulware, D.G. (Department of Physics FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1992-11-15T23:59:59.000Z

    Gott spacetime has closed timelike curves, but no locally anomalous stress energy. A complete orthonormal set of eigenfunctions of the wave operator is found in the special case of a spacetime in which the total deficit angle is 2{pi}. A scalar quantum field theory is constructed using these eigenfunctions. The resultant interacting quantum field theory is not unitary because the field operators can create real, on-shell, particles in the noncausal region. These particles propagate for finite proper time accumulating an arbitrary phase before being annihilated at the same spacetime point as that at which they were created. As a result, the effective potential within the noncausal region is complex, and probability is not conserved. The stress tensor of the scalar field is evaluated in the neighborhood of the Cauchy horizon; in the case of a sufficiently small Compton wavelength of the field, the stress tensor is regular and cannot prevent the formation of the Cauchy horizon.

  12. Sterile Neutrino Fits to Short-Baseline Neutrino Oscillation Measurements

    E-Print Network [OSTI]

    Conrad, J. M.

    2013-01-01T23:59:59.000Z

    This paper reviews short-baseline oscillation experiments as interpreted within the context of one, two, and three sterile neutrino models associated with additional neutrino mass states in the ~1?eV range. Appearance and ...

  13. INTERPLANETARY NETWORK LOCALIZATIONS OF KONUS SHORT GAMMA-RAY BURSTS

    E-Print Network [OSTI]

    Vanderspek, Roland K.

    Between the launch of the Global Geospace Science Wind spacecraft in 1994 November and the end of 2010, the Konus-Wind experiment detected 296 short-duration gamma-ray bursts (including 23 bursts which can be classified ...

  14. Inventories and the short-run dynamics of commodity prices

    E-Print Network [OSTI]

    Pindyck, Robert S.

    1990-01-01T23:59:59.000Z

    I examine the behavior of inventories and their role in the short-run dynamics of commodity production and price. Competitive producers of a storable commodity react to price changes by balancing costs of changing production ...

  15. Short-term CO? abatement in the European power sector

    E-Print Network [OSTI]

    Delarue, Erik D.

    2008-01-01T23:59:59.000Z

    This paper focuses on the possibilities for short term abatement in response to a CO2 price through fuel switching in the European power sector. The model E-Simulate is used to simulate the electricity generation in Europe ...

  16. Short communication Limits to deficit accumulation in elderly people

    E-Print Network [OSTI]

    Mitnitski, Arnold B.

    Short communication Limits to deficit accumulation in elderly people Kenneth Rockwood *, Arnold We evaluated limits to the accumulation of deficits (symptoms, diseases, disabilities) for 33 which, even in developed countries, further deficit accumulation is not sustainable. # 2006 Elsevier

  17. Methods for short-circuit identification and location in automobiles

    E-Print Network [OSTI]

    Crumlin, Alex Justin

    2006-01-01T23:59:59.000Z

    As the number of electrical components in cars increases at a rapid rate, so too does the chance for electrical failure. A method for locating shorts to the chassis of a car is developed in this thesis. The developed ...

  18. Industrial Energy Auditing - A Short Course for Engineers 

    E-Print Network [OSTI]

    Witte, L. C.

    1979-01-01T23:59:59.000Z

    This paper describes an intensive five day short course, directed toward engineers currently working in industry, which provides the participants with the rudiments of industrial energy auditing. Experience has shown that this format of training can...

  19. Abstract: Development and Deployment of a Short Rotation Woody...

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

    highlights a project that will develop a single pass cut and chip harvesting system for short rotation woody crops that will improve the harvesting and logistic costs of processing...

  20. Criteria to determine gas reserves using short time buildup tests

    E-Print Network [OSTI]

    Guerini Franchina, Agostino

    1991-01-01T23:59:59.000Z

    (Member) Robert R. Berg (Member) Kenneth R. Hall (interim Head of Department) December 1991 ABSTRACT Criteria to Determine Gas Reserves Using Short Time Buildup Tests. ( December 1991 ) Agostino Guerini Franchina, Ingeniero de Petroleo...

  1. Short Circuit Analysis of Induction Machines Wind Power Application

    SciTech Connect (OSTI)

    Starke, Michael R [ORNL; Smith, Travis M [ORNL; Howard, Dustin [Georgia Institute of Technology; Harley, Ronald [Georgia Institute of Technology

    2012-01-01T23:59:59.000Z

    he short circuit behavior of Type I (fixed speed) wind turbine-generators is analyzed in this paper to aid in the protection coordination of wind plants of this type. A simple network consisting of one wind turbine-generator is analyzed for two network faults: a three phase short circuit and a phase A to ground fault. Electromagnetic transient simulations and sequence network calculations are compared for the two fault scenarios. It is found that traditional sequence network calculations give accurate results for the short circuit currents in the balanced fault case, but are inaccurate for the un-faulted phases in the unbalanced fault case. The time-current behavior of the fundamental frequency component of the short circuit currents for both fault cases are described, and found to differ significantly in the unbalanced and balanced fault cases

  2. Ultra-short nacelles for low fan pressure ratio propulsors

    E-Print Network [OSTI]

    Peters, Andreas, Ph. D. Massachusetts Institute of Technology

    2014-01-01T23:59:59.000Z

    This thesis addresses the uncharted inlet and nacelle design space for low pressure ratio fans for advanced aeroengines. A key feature in low fan pressure ratio (FPR) propulsors with short inlets and nacelles is the increased ...

  3. Squat exercise biomechanics during short-radius centrifugation

    E-Print Network [OSTI]

    Duda, Kevin R., 1979-

    2007-01-01T23:59:59.000Z

    Artificial gravity (AG) created by short-radius centrifugation is a promising countermeasure to the physiological de-conditioning that results from long-duration spaceflight. However, as on Earth, gravity alone does not ...

  4. SHORT PAPER Zifeng Yang Partha Sarkar Hui Hu

    E-Print Network [OSTI]

    Hu, Hui

    SHORT PAPER Zifeng Yang · Partha Sarkar · Hui Hu Visualization of the tip vortices in a wind along the elevation direction. Z. Yang Á P. Sarkar Á H. Hu (&) Department of Aerospace Engineering, Iowa

  5. Ultra-short ion and neutron pulse production

    DOE Patents [OSTI]

    Leung, Ka-Ngo; Barletta, William A.; Kwan, Joe W.

    2006-01-10T23:59:59.000Z

    An ion source has an extraction system configured to produce ultra-short ion pulses, i.e. pulses with pulse width of about 1 .mu.s or less, and a neutron source based on the ion source produces correspondingly ultra-short neutron pulses. To form a neutron source, a neutron generating target is positioned to receive an accelerated extracted ion beam from the ion source. To produce the ultra-short ion or neutron pulses, the apertures in the extraction system of the ion source are suitably sized to prevent ion leakage, the electrodes are suitably spaced, and the extraction voltage is controlled. The ion beam current leaving the source is regulated by applying ultra-short voltage pulses of a suitable voltage on the extraction electrode.

  6. Water/Wastewater Treatment Plant Field Device Wiring Method Decision Analysis

    E-Print Network [OSTI]

    Dicus, Scott C.

    2011-12-16T23:59:59.000Z

    The choice of field device wiring method for water and wastewater treatment plant design is extremely complex and contains many variables. The choice not only affects short-term startup and equipment costs, but also ...

  7. Modeling the high-field section of a muon helical cooling channel

    SciTech Connect (OSTI)

    Zlobin, A.V.; Barzi, E.; Kashikhin, V.S.; Lamm, M.J.; Lombardo, V.; Lopes, M.L.; Yu, M.; /Fermilab; Johnson, R.P.; Flanagan, G.; Kahn, S.A.; Turenne, M.; /MUONS Inc., Batavia

    2010-05-01T23:59:59.000Z

    This paper describes the conceptual design and parameters of a short model of a high-field helical solenoid for muon beam cooling. Structural materials choices, fabrication techniques and first test results are discussed.

  8. Smooth Field Theories and Homotopy Field Theories

    E-Print Network [OSTI]

    Wilder, Alan Cameron

    2011-01-01T23:59:59.000Z

    CHAPTER 3. FIELD THEORIES Definition 3.2.1. A smooth fielda ’top down’ definition of field theories. Taking as ourin the following. Definition A field theory is a symmetric

  9. Systems building of short span precast concrete bridges

    E-Print Network [OSTI]

    Steele, Marvin

    1975-01-01T23:59:59.000Z

    SYSTEMS BUILDING OF SHORT SPAN PRECAST CONCRETE BRIDGES A Thesis by MARVIN STEELE Submitted to the Graduate College of Texas AIIM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1975 Major... Subject: Civil Engineering SYSTEMS BUILDING OF SHORT SPAN PRECAST CONCRETE BRIDGES A Thesis by MARVIN STEELE Aoproved as to style and content by: (Chairman of Committee) (Head of Department ( mber) fi (Member) May 1975 ABSTRACT Systems Building...

  10. A model for short term electric load forecasting

    E-Print Network [OSTI]

    Tigue, John Robert

    1975-01-01T23:59:59.000Z

    A MODEL FOR SHORT TERM ELECTRIC LOAD FORECASTING A Thesis by JOHN ROBERT TIGUE, III Submitted to the Graduate College of Texas ASM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE May 1975 Major... Subject: Electrical Engineering A MODEL FOR SHORT TERM ELECTRIC LOAD FORECASTING A Thesis by JOHN ROBERT TIGUE& III Approved as to style and content by: (Chairman of Committee) (Head Depart t) (Member) ;(Me r (Member) (Member) May 1975 ABSTRACT...

  11. Infrared near-field imaging and spectroscopy based on thermal or synchrotron radiation

    SciTech Connect (OSTI)

    Peragut, Florian; De Wilde, Yannick, E-mail: yannick.dewilde@espci.fr [ESPCI ParisTech, PSL Research University, CNRS, Institut Langevin, 1 rue Jussieu, F-75005, Paris (France); Brubach, Jean-Blaise; Roy, Pascale [Société Civile Synchrotron SOLEIL, L'Orme des Merisiers, St-Aubin BP48, 91192 Gif-sur-Yvette Cedex (France)

    2014-06-23T23:59:59.000Z

    We demonstrate the coupling of a scattering near-field scanning optical microscope combined with a Fourier transform infrared spectrometer. The set-up operates using either the near-field thermal emission from the sample itself, which is proportional to the electromagnetic local density of states, or with an external infrared synchrotron source, which is broadband and highly brilliant. We perform imaging and spectroscopy measurements with sub-wavelength spatial resolution in the mid-infrared range on surfaces made of silicon carbide and gold and demonstrate the capabilities of the two configurations for super-resolved near-field mid-infrared hyperspectral imaging and that the simple use of a properly chosen bandpass filter on the detector allows one to image the spatial distribution of materials with sub-wavelength resolution by studying the contrast in the near-field images.

  12. Magnetized Hypermassive Neutron Star Collapse: a candidate central engine for short-hard GRBs

    E-Print Network [OSTI]

    Branson C. Stephens; Matthew D. Duez; Yuk Tung Liu; Stuart L. Shapiro; Masaru Shibta

    2007-02-02T23:59:59.000Z

    Hypermassive neutron stars (HMNSs) are equilibrium configurations supported against collapse by rapid differential rotation and likely form as transient remnants of binary neutron star mergers. Though HMNSs are dynamically stable, secular effects such as viscosity or magnetic fields tend to bring HMNSs into uniform rotation and thus lead to collapse. We simulate the evolution of magnetized HMNSs in axisymmetry using codes which solve the Einstein-Maxwell-MHD system of equations. We find that magnetic braking and the magnetorotational instability (MRI) both contribute to the eventual collapse of HMNSs to rotating black holes surrounded by massive, hot accretion tori and collimated magnetic fields. Such hot tori radiate strongly in neutrinos, and the resulting neutrino-antineutrino annihilation could power short-hard GRBs.

  13. The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar

    E-Print Network [OSTI]

    Ellingson, Steven W.

    , Brownsville, TX 78520 and on behalf of the LWA Consortium. ABSTRACT The Long Wavelength Array (LWA), currently accurate geomagnetic storm prediction from the Earth's surface. Both radar and passive receiving techniques sensing techniques. The LWA will also naturally provide a measure of small-scale spatial and temporal

  14. The Long Wavelength Array (LWA): A Large HF/VHF Array for Solar Physics, Ionospheric Science, and Solar Radar

    E-Print Network [OSTI]

    Ellingson, Steven W.

    Consortium #12;Executive Summary The Long Wavelength Array (LWA), currently under construction in New be an excellent receiver for solar radar, potentially demonstrating accurate geomagnetic storm prediction from naturally provide a measure of small-scale spatial and temporal ionospheric structure, a prerequisite

  15. 1004 OPTICS LETTERS / Vol. 23, No. 13 / July 1, 1998 1.5-mm-band wavelength conversion based on

    E-Print Network [OSTI]

    Fejer, Martin M.

    telecommunications band based on difference-frequency generation in periodically poled lithium niobate waveguides converters was proposed.3 That architecture, exploiting the unique properties of DFG-based wavelengthGaAs) or limited homogeneous interaction lengths (in LiNbO3). Another critical issue with guided-wave DFG

  16. Lasers in Surgery and Medicine 36:281288 (2005) Influence of Laser Wavelength and Pulse Duration on

    E-Print Network [OSTI]

    Choi, Bernard

    ; laser heated blood; methemoglobin production; port wine stains; selective photothermolysis INTRODUCTION) such as port wine stain (PWS)birthmarks [1­3],telangiectasias [4], and hemangiomas [5]. PDL parameters of selectively absorbed radiant energy into thermal energy [6]. Laser wavelength, l is chosen to achieve optimal

  17. Summary Leaf reflectance at visible and near-infrared wavelengths (4001000 nm) is related primarily to pigmenta-

    E-Print Network [OSTI]

    Richardson, Andrew D.

    Summary Leaf reflectance at visible and near-infrared wavelengths (400­1000 nm) is related physiology and relationships between plants and their growth environment. We studied reflectance of two co collected from 24 sites and white spruce from 30 sites. Overall, reflectance spectra of the two species were

  18. Tunable, long-wavelength PtSi/SiGe/Si Schottky diode infrared detectors J. R. Jimeneza)

    E-Print Network [OSTI]

    Tunable, long-wavelength PtSi/SiGe/Si Schottky diode infrared detectors J. R. Jimeneza) Faura, Massachusetts 01731 Received 9 March 1995; accepted for publication 31 May 1995 We have fabricated p-type PtSi/SiGe dependent on the applied bias. The variability in the barrier height is obtained by using the SiGe

  19. Damage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength

    E-Print Network [OSTI]

    von der Linde, D.

    to the optical components required to utilize XFEL beams, including radiation damage. Theoretical workDamage threshold of inorganic solids under free-electron-laser irradiation at 32.5 nm wavelength SC were exposed to single 25 fs long pulses of 32.5 nm free-electron-laser radiation at fluences of up

  20. Multi-wavelength study of 14000 star-forming galaxies from the Sloan Digital Sky Survey

    E-Print Network [OSTI]

    Izotov, Y I; Fricke, K J; Henkel, C

    2013-01-01T23:59:59.000Z

    (abridged) We studied a large sample of ~14000 dwarf star-forming galaxies with strong emission lines selected from the Sloan Digital Sky Survey (SDSS) and distributed in the redshift range of z~0-0.6. We modelled spectral energy distributions (SED) of all galaxies which were based on the SDSS spectra in the visible range of 0.38-0.92 micron and included both the stellar and ionised gas emission. These SEDs were extrapolated to the UV and mid-infrared ranges to cover the wavelength range of 0.1-22 micron. The SDSS spectroscopic data were supplemented by photometric data from the GALEX, SDSS, 2MASS, WISE, IRAS, and NVSS all-sky surveys. We derived global characteristics of the galaxies, such as their element abundances, luminosities, and stellar masses. The luminosities and stellar masses range within the sample over ~5 orders of magnitude, thereby linking low-mass and low-luminosity blue compact dwarf (BCD) galaxies to luminous galaxies, which are similar to high-redshift Lyman-break galaxies (LBGs). The lumi...

  1. Multi-wavelength features of Fermi Bubbles as signatures of a Galactic wind

    E-Print Network [OSTI]

    Sarkar, Kartick Chandra; Sharma, Prateek

    2015-01-01T23:59:59.000Z

    Using hydrodynamical simulations, we show that an episode of star formation in the center of the Milky Way, with a star-formation-rate (SFR) $\\sim 0.5$ M$_\\odot$ yr$^{-1}$ for $\\sim 30$ Myr, can produce bubbles that resemble the Fermi Bubbles (FBs), when viewed from the solar position. The morphology, extent and multi-wavelength observations of FBs, especially X-rays, constrain various physical parameters such as SFR, age, and the circum-galactic medium (CGM) density. We show that the interaction of the CGM with the Galactic wind driven by a star formation in the central region can explain the observed surface brightness and morphological features of X-rays associated with the Fermi Bubbles. Furthermore, assuming that cosmic ray electrons are accelerated {\\it in situ} by shocks and/or turbulence, the brightness and morphology of gamma-ray emission and the microwave haze can be explained. The kinematics of the cold and warm clumps in our model also matches with recent observations of absorption lines through t...

  2. Wavelength-Shifting-Fiber Scintillation Detectors for Thermal Neutron Imaging at SNS

    SciTech Connect (OSTI)

    Clonts, Lloyd G [ORNL; Cooper, Ronald G [ORNL; Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Ellis, E Darren [ORNL; Funk, Loren L [ORNL; Hannan, Bruce W [ORNL; Hodges, Jason P [ORNL; Richards, John D [ORNL; Riedel, Richard A [ORNL; Wang, Cai-Lin [ORNL

    2012-01-01T23:59:59.000Z

    We have developed wavelength-Shifting-fiber Scintillator Detector (SSD) with 0.3 m2 area per module. Each module has 154 x 7 pixels and a 5 mm x 50 mm pixel size. Our goal is to design a large area neutron detector offering higher detection efficiency and higher count-rate capability for Time-Of-Flight (TOF) neutron diffraction in Spallation Neutron Source (SNS). A ZnS/6LiF scintillator combined with a novel fiber encoding scheme was used to record the neutron events. A channel read-out-card (CROC) based digital-signal processing electronics and position-determination algorithm was applied for neutron imaging. Neutron-gamma discrimination was carried out using pulse-shape discrimination (PSD). A sandwich flat-scintillator detector can have detection efficiency close to He-3 tubes (about 10 atm). A single layer flat-scintillator detector has count rate capability of 6,500 cps/cm2, which is acceptable for powder diffractometers at SNS.

  3. Elimination of ghosting artifacts from wavelength-shifting fiber neutron detectors

    SciTech Connect (OSTI)

    Wang, C. L.; Diawara, Y.; Hannan, B. W.; Hodges, J. P. [Instrument and Source Design Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States); Clonts, L. G. [Research Accelerator Division, Neutron Sciences Directorate, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

    2013-01-15T23:59:59.000Z

    Misassignment of neutron position (ghosting) produces artifacts which have been observed in wavelength-shifting (WLS) fiber detectors developed for time-of-flight (TOF) neutron powder diffraction. In position-sensitive detectors (PSDs) with WLS fiber encoding, thermal and cold neutrons interact with a monolithic {sup 6}LiF/ZnS:Ag scintillator screen, and scintillation photons are generated and transported through the crossed fibers to photomultipliers (PMTs). The neutron position is determined by photon counts in the PMTs within a preset time window. Ghosting occurs when neutrons hit the group boundaries of two neighboring PMTs for x-position multiplexing, which is modeled as resulting from a long travel length (about 3-5 mm) of a small number of scintillation photons. This model is supported by the change observed in aperture images when the threshold number for photon-pulses was adjusted for neutron event determination. When the threshold number of photon-pulses was set above 10 for each PMT, the ghost peaks in the aperture images and TOF spectra of powder diffraction were strongly suppressed or completely eliminated, and the intrinsic background levels of the WLS detectors were significantly reduced. Our result indicates that WLS fiber detector is a promising alternative for {sup 3}He PSDs for neutron scattering.

  4. Elimination of ghosting artifacts from wavelength-shifting fiber neutron detectors

    SciTech Connect (OSTI)

    Clonts, Lloyd G [ORNL; Diawara, Yacouba [ORNL; Hannan, Bruce W [ORNL; Hodges, Jason P [ORNL; Wang, Cai-Lin [ORNL

    2013-01-01T23:59:59.000Z

    Misassignment of neutron position (ghosting) produces artifacts, which have been observed in wavelength-shifting (WLS) fiber detectors developed for time-of-flight (TOF) neutron powder diffraction. In position-sensitive detectors (PSDs) with WLS fiber encoding, thermal and cold neutrons interact with a monolithic 6LiF/ZnS:Ag scintillator screen, and scintillation photons are generated and transported through the crossed fibers to photomultipliers (PMTs). The neutron position is determined by photon counts in PMTs within a preset time window. Ghosting occurs when neutrons hit the group boundaries of two neighboring PMTs for x-position multiplexing, which is modeled as resulting from a long travel length (about 3-5 mm) of a small number of scintillation photons. This model is supported by the change observed in aperture images when the threshold number for photon-pulses was adjusted for a neutron event determination. When the threshold number of photon-pulses was set above 10 for each PMT, the ghost peaks in the aperture images and TOF spectra of powder diffraction were strongly suppressed or completely eliminated, and the intrinsic background levels of the WLS detectors were significantly reduced. Our result indicates that WLS fiber detector is a promising alternative for 3He PSDs for neutron scattering.

  5. The Arecibo Methanol Maser Galactic Plane Survey - II: Statistical and Multi-wavelength Counterpart Analysis

    E-Print Network [OSTI]

    Jagadheep D. Pandian; Paul F. Goldsmith

    2007-08-23T23:59:59.000Z

    We present an analysis of the properties of the 6.7 GHz methanol maser sample detected in the Arecibo Methanol Maser Galactic Plane Survey. The distribution of the masers in the Galaxy, and statistics of their multi-wavelength counterparts is consistent with the hypothesis of 6.7 GHz maser emission being associated with massive young stellar objects. Using the detection statistics of our survey, we estimate the minimum number of methanol masers in the Galaxy to be 1275. The l-v diagram of the sample shows the tangent point of the Carina-Sagittarius spiral arm to be around 49.6 degrees, and suggests occurrence of massive star formation along the extension of the Crux-Scutum arm. A Gaussian component analysis of the maser spectra shows the mean line-width to be 0.38 km/s which is more than a factor of two larger than what has been reported in the literature. We also find no evidence that faint methanol masers have different properties than those of their bright counterparts.

  6. Perfect sub-wavelength metamaterial fishnet-like film absorbers for THz applications

    SciTech Connect (OSTI)

    Shchegolov, Dmitry [Los Alamos National Laboratory; Azad, Abul K [Los Alamos National Laboratory; O' Hara, John F [Los Alamos National Laboratory; Smirnova, Evgenya I [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    We present two designs of robust, easy to manufacture meta material-based films of sub-wavelength thickness capable of full absorption of the incident terahertz (THz) radiation at certain frequencies. Both designs can be either made polarization sensitive, or have 90{sup o} rotation symmetry, which works equally well for waves of any polarization provided the incident angle is zero. All our designs work for a wide range of angles of incidence, and even if the films are optimized for normal incidence the absorption remains greater than 99% for angles up to {approx}35{sup o} in the TE and {approx}65{sup o} in the TM case. In the first design the maximum absorption frequency shifts considerably with angle, and in the second design the maximum absorption frequency remains almost the same at any angle. Theory, simulation data, and recent experimental results are all in a good agreement, and will be reported in the presentation. Having a low heat capacity these absorbers combined with thermo detectors can be utilized for precise frequency-selective detection of THz radiation.

  7. The Spectrum of Thorium from 250 nm to 5500 nm: Ritz Wavelengths and Optimized Energy Levels

    E-Print Network [OSTI]

    Redman, Stephen L; Sansonetti, Craig J

    2013-01-01T23:59:59.000Z

    We have made precise observations of a thorium-argon hollow cathode lamp emission spectrum in the region between 350 nm and 1175 nm using a high-resolution Fourier transform spectrometer. Our measurements are combined with results from seven previously published thorium line lists (Giacchetti et al. 1974; Zalubas & Corliss 1974; Zalubas 1976; Palmer & Engleman 1983; Engleman et al. 2003; Lovis & Pepe 2007; Kerber et al. 2008) to re-optimize the energy levels of neutral, singly-, and doubly-ionized thorium (Th I, Th II, and Th III). Using the optimized level values, we calculate accurate Ritz wavelengths for 19679 thorium lines between 250 nm and 5500 nm (40000 1/cm to 1800 1/cm). We have also found 102 new thorium energy levels. A systematic analysis of previous measurements in light of our new results allows us to identify and propose corrections for systematic errors in Palmer & Engleman (1983) and typographical errors and incorrect classifications in Kerber et al. (2008). We also found a la...

  8. Electro-optical SLS devices for operating at new wavelength ranges

    DOE Patents [OSTI]

    Osbourn, Gordon C. (Albuquerque, NM)

    1986-01-01T23:59:59.000Z

    An intrinsic semiconductor electro-optical device includes a p-n junction intrinsically responsive, when cooled, to electromagnetic radiation in the wavelength range of 8-12 um. The junction consists of a strained-layer superlattice of alternating layers of two different III-V semiconductors having mismatched lattice constants when in bulk form. A first set of layers is either InAs.sub.1-x Sb.sub.x (where x is aobut 0.5 to 0.7) or In.sub.1-x Ga.sub.x As.sub.1-y Sb.sub.y (where x and y are chosen such that the bulk bandgap of the resulting layer is about the same as the minimum bandgap in the In.sub.1-x Ga.sub.x As.sub.1-y Sb.sub.y family). The second set of layers has a lattice constant larger than the lattice constant of the layers in the first set.

  9. Near-Field Magneto-Optical Microscope

    DOE Patents [OSTI]

    Vlasko-Vlasov, Vitalii; Welp, Ulrich; and Crabtree, George W.

    2005-12-06T23:59:59.000Z

    A device and method for mapping magnetic fields of a sample at a resolution less than the wavelength of light without altering the magnetic field of the sample is disclosed. A device having a tapered end portion with a magneto-optically active particle positioned at the distal end thereof in communication with a fiber optic for transferring incoming linearly polarized light from a source thereof to the particle and for transferring reflected light from the particle is provided. The fiber optic has a reflective material trapping light within the fiber optic and in communication with a light detector for determining the polarization of light reflected from the particle as a function of the strength and direction of the magnetic field of the sample. Linearly polarized light from the source thereof transferred to the particle positioned proximate the sample is affected by the magnetic field of the sample sensed by the particle such that the difference in polarization of light entering and leaving the particle is due to the magnetic field of the sample. Relative movement between the particle and sample enables mapping.

  10. Conference Paper NFO-7:7th International Conference on Near-Field Optics and Related Technologies

    SciTech Connect (OSTI)

    Prof.Dr. Lukas Novotny

    2004-10-18T23:59:59.000Z

    The seventh conference in the NFO conference series, held here in Rochester, provided to be the principal forum for advances in sub-wavelength optics, near-field optical microscopy, local field enhancement, instrumental developments and the ever-increasing range of applications. This conference brought together the diverse scientific communities working on the theory and application of near-field optics (NFO) and related techniques.

  11. Quantum mechanics of a charged particle in a background magnetic field interacting with linearized gravitational waves

    E-Print Network [OSTI]

    Sunandan Gangopadhyay; Anirban Saha

    2012-04-02T23:59:59.000Z

    We consider the dynamics of a charged particle interacting with background electromagnetic field under the influence of linearized gravitational waves in the long wave-length and low-velocity limit. Following the prescription in \\cite{speli}, the system is quantized and the Hamiltonian is then solved by using standard algebraic iterative methods. The solution is in conformity with the classical analysis and shows the possibility of tuning the frequency by changing the magnetic field to set up resonance.

  12. Electrostatic waves in carbon nanotubes with an axial magnetic field

    SciTech Connect (OSTI)

    Abdikian, Alireza [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of)] [Department of Physics, Malayer University, Malayer 65719-95863 (Iran, Islamic Republic of); Bagheri, Mehran [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)] [Laser and Plasma Research Institute, Shahid Beheshti University, G. C., Evin, Tehran 19835-63113 (Iran, Islamic Republic of)

    2013-10-15T23:59:59.000Z

    Based on a linearized hydrodynamic model and within the quasi-static approximation, the dispersion relation of electrostatic waves propagating through single-walled carbon nanotubes subject to an axial magnetic field is theoretically explored. In the classical limit, we obtain two main possible waves which in turn are divided into two branches, a low-frequency acoustical and a high-frequency optical plasmon branch. In the quantum case, we have found that the dispersion relation is substantially modified when the electron wavelength becomes large enough compared to the propagation wavelength of the electrostatic waves in the quantum plasma. We also show that the axial magnetic field manifest itself on the perturbed electron density through the quantum term and gives rise to the propagation of the electrostatic waves within the quantum plasma. As a result, the effect of the magnetic field is pronounced in the plasma dispersion relations in such a way that their curves approach to zero when the magnetic field is weak; and for the strong magnetic field, they asymptotically meet the constant lines.

  13. Numerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water

    E-Print Network [OSTI]

    Zhigilei, Leonid V.

    Numerical modeling of short pulse laser interaction with Au nanoparticle surrounded by water Alexey, University of Virginia, USA Available online 3 February 2007 Abstract Short pulse laser interaction modeling; Nanoparticles; Cell targeting; Laser damage 1. Introduction Short pulse laser irradiation

  14. Magnetic Field Safety Magnetic Field Safety

    E-Print Network [OSTI]

    McQuade, D. Tyler

    Magnetic Field Safety Training #12;Magnetic Field Safety Strong Magnetic Fields exist around energized magnets. High magnetic fields alone are a recognized hazard only for personnel with certain medical conditions such as pacemakers, magnetic implants, or embedded shrapnel. In addition, high magnetic

  15. Quantum-noise randomized data encryption for wavelength-division-multiplexed fiber-optic networks

    SciTech Connect (OSTI)

    Corndorf, Eric; Liang Chuang; Kanter, Gregory S.; Kumar, Prem; Yuen, Horace P. [Center for Photonic Communication and Computing, Department of Electrical and Computer Engineering, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208 (United States)

    2005-06-15T23:59:59.000Z

    We demonstrate high-rate randomized data-encryption through optical fibers using the inherent quantum-measurement noise of coherent states of light. Specifically, we demonstrate 650 Mbit/s data encryption through a 10 Gbit/s data-bearing, in-line amplified 200-km-long line. In our protocol, legitimate users (who share a short secret key) communicate using an M-ry signal set while an attacker (who does not share the secret key) is forced to contend with the fundamental and irreducible quantum-measurement noise of coherent states. Implementations of our protocol using both polarization-encoded signal sets as well as polarization-insensitive phase-keyed signal sets are experimentally and theoretically evaluated. Different from the performance criteria for the cryptographic objective of key generation (quantum key-generation), one possible set of performance criteria for the cryptographic objective of data encryption is established and carefully considered.

  16. A loss-based, magnetic field sensor implemented in a ferrofluid infiltrated microstructured polymer optical fiber

    SciTech Connect (OSTI)

    Candiani, A. [Foundation for Research and Technology-Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), Heraklion 70013 Greece (Greece); Department of Information Engineering (DII), University of Parma, Parma 43124 (Italy); Argyros, A.; Leon-Saval, S. G.; Lwin, R. [Institute of Photonics and Optical Science (IPOS), School of Physics, The University of Sydney, Sydney (Australia); Selleri, S. [Department of Information Engineering (DII), University of Parma, Parma 43124 (Italy); Pissadakis, S., E-mail: pissas@iesl.forth.gr [Foundation for Research and Technology-Hellas (FORTH), Institute of Electronic Structure and Laser (IESL), Heraklion 70013 Greece (Greece)

    2014-03-17T23:59:59.000Z

    We report an in-fiber magnetic field sensor based on magneto-driven optical loss effects, while being implemented in a ferrofluid infiltrated microstructured polymer optical fiber. We demonstrate that magnetic field flux changes up to 2000 gauss can be detected when the magnetic field is applied perpendicular to the fiber axis. In addition, the sensor exhibits high polarization sensitivity for the interrogated wavelengths, providing the possibility of both field flux and direction measurements. The underlying physical and guidance mechanisms of this sensing transduction are further investigated using spectrophotometric, light scattering measurements, and numerical simulations, suggesting photonic Hall effect as the dominant physical, transducing mechanism.

  17. Tunable coherent radiation at soft X-ray wavelengths: Generation and interferometric applications

    SciTech Connect (OSTI)

    Rosfjord, Kristine Marie

    2004-07-01T23:59:59.000Z

    The availability of high power, spectrally and spatially coherent soft x-rays (SXR) would facilitate a wide variety of experiments as this energy region covers the primary resonances of many magnetic and biological materials. Specifically, there are the carbon and oxygen K-edges that are critical for biological imaging in the water window and the L-edges of iron, nickel, and cobalt for which imaging and scattering studies can be performed. A new coherent soft X-ray branchline at the Advanced Light Source has begun operation (beamline 12.0.2). Using the third harmonic from an 8 cm period undulator, this branch delivers coherent soft x-rays with photon energies ranging from 200eV to 1keV. This branchline is composed of two sub-branches one at 14X demagnification and the other 8X demagnification. The former is optimized for use at 500eV and the latter at 800eV. Here the expected power from the third harmonic of this undulator and the beamline design and characterization is presented. The characterization includes measurements on available photon flux as well as a series of double pinhole experiments to determine the coherence factor with respect to transverse distance. The first high quality Airy patterns at SXR wavelengths are created with this new beamline. The operation of this new beamline allows for interferometry to be performed in the SXR region. Here an interferometric experiment designed to directly determine the index of refraction of a material under test is performed. Measurements are first made in the EUV region using an established beamline (beamline12.0.1) to measure silicon, ruthenium and tantalum silicon nitride. This work is then extended to the SXR region using beamline 12.0.2 to test chromium and vanadium.

  18. Non-commutative Field Theory with Twistor-like Coordinates

    E-Print Network [OSTI]

    Tomasz R. Taylor

    2007-09-16T23:59:59.000Z

    We consider quantum field theory in four-dimensional Minkowski spacetime, with the position coordinates represented by twistors instead of the usual world-vectors. Upon imposing canonical commutation relations between twistors and dual twistors, quantum theory of fields described by non-holomorphic functions of twistor variables becomes manifestly non-commutative, with Lorentz symmetry broken by a time-like vector. We discuss the free field propagation and its impact on the short- and long-distance behavior of physical amplitudes in perturbation theory. In the ultraviolet limit, quantum field theories in twistor space are generically less divergent than their commutative counterparts. Furthermore, there is no infrared--ultraviolet mixing problem.

  19. Short-term energy outlook: Quarterly projections. Second quarter 1995

    SciTech Connect (OSTI)

    NONE

    1995-05-02T23:59:59.000Z

    The Energy Information Administration (EIA) prepares quarterly, short-term energy supply, demand, and price projections for publication in February, May, August, and November in the Short-Term Energy Outlook (Outlook). An annual supplement analyzes the performance of previous forecasts, compares recent projections with those of other forecasting services, and discusses current topics related to the short-term energy markets. (See Short-Term Energy Outlook Annual Supplement, DOE/EIA-0202.) The forecast period for this issue of the Outlook extends from the second quarter of 1995 through the fourth quarter of 1996. Values for the first quarter of 1995, however, are preliminary EIA estimates (for example, some monthly values for petroleum supply and disposition are derived in part from weekly data reported in the Weekly Petroleum Status Report) or are calculated from model simulations using the latest exogenous information available (for example, electricity sales and generation are simulated using actual weather data). The historical energy data, compiled into the second quarter 1995 version of the Short-Term Integrated Forecasting System (STIFS) database, are mostly EIA data regularly published in the Monthly Energy Review, Petroleum Supply Monthly, and other EIA publications. Minor discrepancies between the data in these publications and the historical data in this Outlook are due to independent rounding. The STIFS database is archived quarterly and is available from the National Technical Information Service.

  20. An improved model for flashing flow in short tubes

    SciTech Connect (OSTI)

    Tilton, J.D.; Kornhauser, A.A. [Virginia Polytechnic Inst. and State Univ., Blacksburg, VA (United States). Dept. of Mechanical Engineering

    1996-12-31T23:59:59.000Z

    Short tube restrictors are commonly used as expansion devices in refrigeration and heat pumping systems. Flashing flow through short tubes is choked, i.e. independent of downstream conditions. Flow rate is typically predicted by empirically correcting the flow rate of compressed liquid from upstream pressure to saturation pressure at upstream temperature. The empirical correction factors depend on pressure and temperature, on short tube geometry, and on the refrigerant used. This work extends and improves a model of short tube flow based on the physics of the observed flow phenomena. Short tube flow is believed to consist of a core of superheated liquid surrounded by an annulus of vapor. Evaporation is driven by heat transfer form the core to tine interface, and the flow is choked by the evaporated vapor. Flow rate is modeled by calculating the heat transfer rate, the evaporation rate, and the choking effect of the vapor. The model attempts to improve on previous work by improving the accuracy with which thermodynamic properties are approximated, by improving the heat transfer model, and by including the effects of frictional heating of the liquid. In comparisons with experimental data it is found that the improved thermodynamic modeling increases accuracy, but the change to the heat transfer model reduces accuracy. For the data examined the effects of the frictional heating are small. The heat transfer model is based on an existing analytic solution with a mixing-length turbulence model. It appears that this model must be further improved, perhaps through empirical modification.