Sample records for two-photon channel shows

  1. Search for the Standard Model Higgs boson in the two photon decay channel with the ATLAS detector at the LHC

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for the Standard Model Higgs boson in the two photon decay channel is reported, using 1.08 fb?11.08 fb[superscript ?1] of proton–proton collision data at a centre-of-mass energy of 7 TeV recorded by the ATLAS ...

  2. A Search For the Higgs Boson in CMS in the Two Photon Decay Channel

    E-Print Network [OSTI]

    Christopher Palmer

    2011-09-30T23:59:59.000Z

    We report on a search for SM Higgs Boson in the two photon decay mode conducted by the CMS experiment with the data accumulated during the 2010 & 2011 running of the LHC at center of mass collision energy of 7 TeV.

  3. Fast scanning two-photon microscopy

    E-Print Network [OSTI]

    Chang, Jeremy T

    2010-01-01T23:59:59.000Z

    Fast scanning two-photon microscopy coupled with the use light activated ion channels provides the basis for fast imaging and stimulation in the characterization of in vivo neural networks. A two-photon microscope capable ...

  4. Two-photon wave mechanics

    E-Print Network [OSTI]

    Brian J. Smith; M. G. Raymer

    2007-02-21T23:59:59.000Z

    The position-representation wave function for multi-photon states and its equation of motion are introduced. A major strength of the theory is that it describes the complete evolution (including polarization and entanglement) of multi-photon states propagating through inhomogeneous media. As a demonstration of the two-photon wave function's use, we show how two photons in an orbital-angular-momentum entangled state decohere upon propagation through a turbulent atmosphere.

  5. Full Quantum Analysis of Two-Photon Absorption Using Two-Photon Wavefunction: Comparison with One-Photon Absorption

    E-Print Network [OSTI]

    Toshihiro Nakanishi; Hirokazu Kobayashi; Kazuhiko Sugiyama; Masao Kitano

    2009-06-01T23:59:59.000Z

    For dissipation-free photon-photon interaction at the single photon level, we analyze one-photon transition and two-photon transition induced by photon pairs in three-level atoms using two-photon wavefunctions. We show that the two-photon absorption can be substantially enhanced by adjusting the time correlation of photon pairs. We study two typical cases: Gaussian wavefunction and rectangular wavefunction. In the latter, we find that under special conditions one-photon transition is completely suppressed while the high probability of two-photon transition is maintained.

  6. Two-Photon Emission from Semiconductors

    E-Print Network [OSTI]

    Alex Hayat; Pavel Ginzburg; Meir Orenstein

    2007-10-25T23:59:59.000Z

    We report the first experimental observations of two-photon emission from semiconductors, to the best of our knowledge, and develop a corresponding theory for the room-temperature process. Spontaneous two-photon emission is demonstrated in optically-pumped bulk GaAs and in electrically-driven GaInP/AlGaInP quantum wells. Singly-stimulated two-photon emission measurements demonstrate the theoretically predicted two-photon optical gain in semiconductors - a necessary ingredient for any realizations of future two-photon semiconductor lasers. Photon-coincidence experiment validates the simultaneity of the electrically-driven GaInP/AlGaInP two-photon emission, limited only by detector's temporal resolution.

  7. Two-photon collisions and QCD

    SciTech Connect (OSTI)

    Gunion, J.F.

    1980-05-01T23:59:59.000Z

    A critical review of the applications of QCD to low- and high-p/sub T/ interactions of two photons is presented. The advantages of the two-photon high-p/sub T/ tests over corresponding hadronic beam and/or target tests of QCD are given particular emphasis.

  8. Two-photon transitions in primordial hydrogen recombination

    E-Print Network [OSTI]

    Christopher M. Hirata

    2008-05-20T23:59:59.000Z

    The subject of cosmological hydrogen recombination has received much attention recently because of its importance to predictions for and cosmological constraints from CMB observations. While the central role of the two-photon decay 2s->1s has been recognized for many decades, high-precision calculations require us to consider two-photon decays from the higher states ns,nd->1s (n>=3). Simple attempts to include these processes in recombination calculations have suffered from physical problems associated with sequences of one-photon decays, e.g. 3d->2p->1s, that technically also produce two photons. These correspond to resonances in the two-photon spectrum that are optically thick, necessitating a radiative transfer calculation. We derive the appropriate equations, develop a numerical code to solve them, and verify the results by finding agreement with analytic approximations to the radiative transfer equation. The related processes of Raman scattering and two-photon recombination are included using similar machinery. Our results show that early in recombination the two-photon decays act to speed up recombination, reducing the free electron abundance by 1.3% relative to the standard calculation at z=1300. However we find that some photons between Ly-alpha and Ly-beta are produced, mainly by 3d->1s two-photon decay and 2s->1s Raman scattering. At later times these photons redshift down to Ly-alpha, excite hydrogen atoms, and act to slow recombination. Thus the free electron abundance is increased by 1.3% relative to the standard calculation at z=900. The implied correction to the CMB power spectrum is neligible for the recently released WMAP and ACBAR data, but at Fisher matrix level will be 7 sigma for Planck. [ABRIDGED

  9. Enhanced Two-Photon Processes in Quantum Dots inside Photonic Crystal Nanocavities and Quantum Information Processing Applications

    E-Print Network [OSTI]

    Ziliang Lin; Jelena Vuckovic

    2009-07-02T23:59:59.000Z

    We show that the two-photon transition rates of quantum dots coupled to nanocavities are enhanced by up to 8 orders of magnitude relative to quantum dots in bulk host. We then propose how to take advantage of this enhancement to implement coherent quantum dot excitation by two-photon absorption, entangled photon pair generation by two-photon spontaneous emission, and single-photon generation at telecommunication wavelengths by two-photon stimulated and spontaneous emission.

  10. A Measurement of the Recently Discovered Higgs Boson in the Decay into Two Photons with Associated Jets, Using

    E-Print Network [OSTI]

    Sheldon, Nathan D.

    A Measurement of the Recently Discovered Higgs Boson in the Decay into Two Photons with Associated or not this is the Higgs boson as predicted by the Standard Model of Particle Physics (SM). Experimentally measuring of the Higgs boson via its decay into two photons, which was one of the key discovery channels. Part

  11. Effect of morphology and solvent on two-photon absorption of nano zinc oxide

    SciTech Connect (OSTI)

    Kavitha, M.K. [Department of Chemistry, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India); Haripadmam, P.C.; Gopinath, Pramod; Krishnan, Bindu [Department of Physics, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India); John, Honey, E-mail: honey@iist.ac.in [Department of Chemistry, Indian Institute of Space Science and Technology, Valiamala, Thiruvananthapuram 695547, Kerala (India)

    2013-05-15T23:59:59.000Z

    Highlights: ? ZnO nanospheres and triangular structures synthesis by novel precipitation technique. ? The effect of precursor concentration on the size and shape of nano ZnO. ? Open aperture Z-scan measurements of the ZnO nanoparticle dispersions. ? Nanospheres exhibit higher two photon absorption coefficient than triangular nanostructures. ? Nanospheres dispersed in water exhibit higher two photon absorption coefficient than its dispersion in 2-propanol. - Abstract: In this paper, we report the effect of morphology and solvent on the two-photon absorption of nano zinc oxide. Zinc oxide nanoparticles in two different morphologies like nanospheres and triangular nanostructures are synthesized by novel precipitation technique and their two-photon absorption coefficient is measured using open aperture Z-scan technique. Experimental results show that the zinc oxide nanospheres exhibit higher two-photon absorption coefficient than the zinc oxide triangular nanostructures. The zinc oxide nanospheres dispersed in water exhibit higher two-photon absorption coefficient than that of its dispersion in 2-propanol. The zinc oxide nanospheres dispersed in water shows a decrease in two-photon absorption coefficient with an increase in on-axis irradiance. The result confirms the dependence of shape and solvent on the two-photon absorption of nano zinc oxide.

  12. Two-Photon Correlations in Atomic Transitions

    E-Print Network [OSTI]

    Fry, Edward

    1973-01-01T23:59:59.000Z

    , and m is the magnetic quantum number in the F repre- sentation. The two photons are represented as plane waves whose directions of travel are k, and k, , respectively, and whose helicities, +1, are denoted by a, and o, , respectively, Detector 1... effects, is S &X dO, dQ, 2 &o," l~(1)lo, &&c2 l~(2)lorn&l IQg ~ Qy 02 02 Pf ~ 7tl~~ y gf y Nlf gg SIQ 75I (-1) '"P(F, , m, )(2F +1)' && C(F1F, ; m, m, -m)C(FlF, ; m', m, ?m')C(F1F&, m, mz ?m) && C (FlF&, m ', m& ?m') W (J& JF& F; 1 I ) W (J&JF&F; 1I...

  13. Non-local geometric phase in two-photon interferometry

    E-Print Network [OSTI]

    Anthony Martin; Olivier Alibart; Jean-Christoph Flesch; Joseph Samuel; Supurna Sinha; Sébastien Tanzilli; Anders Kastberg

    2012-01-05T23:59:59.000Z

    We report the experimental observation of the nonlocal geometric phase in Hanbury Brown-Twiss polarized intensity interferometry. The experiment involves two independent, polar- ized, incoherent sources, illuminating two polarized detectors. Varying the relative polarization angle between the detectors introduces a geometric phase equal to half the solid angle on the Poincar\\'e sphere traced out by a pair of single photons. Local measurements at either detector do not reveal the effect of the geometric phase, which appears only in the coincidence counts between the two detectors, showing a genuinely nonlocal effect. We show experimentally that coincidence rates of photon arrival times at separated detectors can be controlled by the two photon geometric phase. This effect can be used for manipulating and controlling photonic entanglement.

  14. Resonance production in two-photon interactions

    SciTech Connect (OSTI)

    Roe, N.A.

    1989-02-01T23:59:59.000Z

    Resonance production in two-photon interactions is studied using data collected with the ASP detector at the PEP e/sup +/e/sup /minus// storage ring located at the Stanford Linear Accelerator Center. The ASP detector is a non-magnetic lead-glass calorimeter constructed from 632 lead-glass bars. It covers 94% of 4..pi.. in solid angle, extending to within 20/degree/ of the beamline. Lead-scintillator calorimeters extend the coverage to within 21 mr of the beamline on both sides. Energy resolution of ..sqrt..E/10%, where E is the energy is GeV, is achieved for electrons and photons in the lead-glass calorimeter, and particle trajectories are reconstructed with high efficiency. A total luminosity of 108 pb/sup /minus/1/ was collected with the ASP detector at a center-of-mass energy of 29 GeV. The observed process is e/sup +/e/sup /minus// ..-->.. e/sup +/e/sup /minus//..gamma..*..gamma..* ..-->.. e/sup +/e/sup /minus//X, is a pseudoscalar resonance (J/sup PC/ = 0/sup /minus/+/) and ..gamma..* is a virtual (mass /ne/ 0) photon. The outgoing electrons scatter down the beampipe and are not detected. The observed resonances are the /eta/ and /eta/' mesons, with masses of 549 and 958 MeV, respectively. They are detected in the ..gamma gamma.. decay mode; a total of 2380 +- 49 /eta/ ..-->.. ..gamma gamma.. and 568 +- 26 /eta/' ..-->.. ..gamma gamma.. events are observed. From the number of events, the detection efficiency, and the calculated production cross sections the radiative widths, GAMMA/sub ..gamma gamma../, of the /eta/ and /eta/' were measured and found to be: GAMMA/sub ..gamma gamma../(/eta/) = .481 +- .010 +- .047keV and GAMMA/sub ..gamma gamma../(/eta/') = 4.71 +- .22 +- .70keV. These results are in good agreement with the world average values. 67 refs., 42 figs., 20 tabs.

  15. Coherent Control of Resonant Two-Photon Transitions by Counter-Propagating Ultrashort Pulse Pairs

    E-Print Network [OSTI]

    Lee, Woojun; Kim, Kyungtae; Ahn, Jaewook

    2015-01-01T23:59:59.000Z

    We describe optimized coherent control methods for two-photon transitions in atoms of a ladder-type three-state energy configuration. Our approach is based on the spatial coherent control scheme which utilizes counter-propagating ultrashort laser pulses to produce complex excitation patterns in an extended space. Since coherent control requires constructive interference of constituent transition pathways, applying it to an atomic transition with a specific energy configuration requires specially designed laser pulses. Here, we show, in an experimental demonstration, that the two-photon transition with an intermediate resonant energy state can be coherently controlled and retrieved out from the resonance-induced background, when phase-flipping of the laser spectrum near the resonant intermediate transition is used. A simple reason for this behavior is the fact that the transition amplitude function (to be added to give an overall two-photon transition) changes its sign at the intermediate resonant frequency, t...

  16. The role of pump coherence in two-photon interferometry

    E-Print Network [OSTI]

    J. Liang; S. M. Hendrickson; T. B. Pittman

    2010-12-20T23:59:59.000Z

    We use a parametric down-conversion source pumped by a short coherence-length continuous-wave (CW) diode laser to perform two-photon interferometry in an intermediate regime between the more familiar Franson-type experiments with a long coherence-length pump laser, and the short pulsed pump "time-bin" experiments pioneered by Gisin's group. The use of a time-bin-like Mach-Zehnder interferometer in the CW pumping beam induces coherence between certain two-photon amplitudes, while the CW nature of the experiment prevents the elimination of remaining incoherent ones. The experimental results highlight the role of pump coherence in two-photon interferometry.

  17. Single Photon Source Using Laser Pulses and Two-Photon Absorption

    E-Print Network [OSTI]

    B. C. Jacobs; T. B. Pittman; J. D. Franson

    2006-03-17T23:59:59.000Z

    We have previously shown that two-photon absorption (TPA) and the quantum Zeno effect can be used to make deterministic quantum logic devices from an otherwise linear optical system. Here we show that this type of quantum Zeno gate can be used with additional two-photon absorbing media and weak laser pulses to make a heralded single photon source. A source of this kind is expected to have a number of practical advantages that make it well suited for large scale quantum information processing applications.

  18. All-Optical Switching Using the Quantum Zeno Effect and Two-Photon Absorption

    E-Print Network [OSTI]

    B. C. Jacobs; J. D. Franson

    2009-05-08T23:59:59.000Z

    We have previously shown that the quantum Zeno effect can be used to implement quantum logic gates for quantum computing applications, where the Zeno effect was produced using a strong two-photon absorbing medium. Here we show that the Zeno effect can also be used to implement classical logic gates whose inputs and outputs are high-intensity fields (coherent states). The operation of the devices can be understood using a quasi-static analysis, and their switching times are calculated using a dynamic approach. The two-photon absorption coefficient of rubidium vapor is shown to allow operation of these devices at relatively low power levels.

  19. Two photon couplings of the lightest isoscalars from BELLE data

    SciTech Connect (OSTI)

    Dai, Lingyun [JLAB; Pennington, Michael R. [JLAB

    2014-09-01T23:59:59.000Z

    Amplitude Analysis of two photon production of ?? and K?K, using S-matrix constraints and fitting all available data, including the latest precision results from Belle, yields a single partial wave solution up to 1.4 GeV. The two photon couplings of the ?/f0(500), f0(980) and f2(1270) are determined from the residues of the resonance poles.

  20. Two photon couplings of the lightest isoscalars from BELLE data

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

    Dai, Lingyun [JLAB; Pennington, Michael R. [JLAB

    2014-09-01T23:59:59.000Z

    Amplitude Analysis of two photon production of ?? and K?K, using S-matrix constraints and fitting all available data, including the latest precision results from Belle, yields a single partial wave solution up to 1.4 GeV. The two photon couplings of the ?/f0(500), f0(980) and f2(1270) are determined from the residues of the resonance poles.

  1. Coherent Control of Angular Momentum Transfer in Resonant Two-Photon Light-Matter Interaction

    SciTech Connect (OSTI)

    Malik, D. A.; Kimel, A. V.; Kirilyuk, A.; Rasing, Th.; Zande, W. J. van der [Radboud University Nijmegen, Institute for Molecules and Materials, P.O. Box 9010, NL-6500 GL Nijmegen (Netherlands)

    2010-04-02T23:59:59.000Z

    We show experimentally and theoretically that a polarization-shaped femtosecond laser pulse with a zero net angular momentum creates a net angular momentum in atomic rubidium during resonant two-photon excitation. The necessary conditions for the creation of a nonzero angular momentum as well as the excitation efficiencies are analyzed in the framework of second-order time-dependent perturbation theory.

  2. Search for Anomalous Production of Events with Two Photons and Additional Energetic Objects at CDF

    SciTech Connect (OSTI)

    Aaltonen, T.; /Helsinki Inst. of Phys.; Adelman, J.; /Chicago U., EFI; Alvarez Gonzalez, B.; /Oviedo U. /Cantabria Inst. of Phys.; Amerio, S.; /Padua U. /INFN, Padua; Amidei, D.; /Michigan U.; Anastassov, A.; /Northwestern U.; Annovi, A.; /Frascati; Antos, J.; /Comenius U. /Kosice, IEF; Apollinari, G.; /Fermilab; Apresyan, A.; /Purdue U.; Arisawa, T.; /Waseda U. /Dubna, JINR

    2009-10-01T23:59:59.000Z

    The authors present results of a search for anomalous production of two photons together with an electron, muon, {tau} lepton, missing transverse energy, or jets using p{bar p} collision data from 1.1-2.0 fb{sup -1} of integrated luminosity collected by the Collider Detector at Fermilab (CDF). The event yields and kinematic distributions are examined for signs for new physics without favoring a specific model of new physics. The results are consistent with the standard model expectations. The search employs several new analysis techniques that significantly reduce instrumental backgrounds in channels with an electron and missing transverse energy.

  3. submitted to CALICO 2007 (The Computer Assisted Language Instruction Consortium Meeting) Learning to Show You're Listening: A Back-Channel Trainer for Arabic

    E-Print Network [OSTI]

    Ward, Nigel

    a training sequence which enables the acquisition of basic Arabic back-channel skill, namely to Show You're Listening: A Back-Channel Trainer for Arabic Rafael Escalante, Nigel G. Ward, Yaffa Al Bayyari, Thamar Solorio 100 word abstract Good listeners generally produce back-channel feedback, and do

  4. Waveguide QED: Two Photons, Many Qubits, and a Mirror

    E-Print Network [OSTI]

    Yao-Lung L. Fang; Harold U. Baranger

    2015-02-12T23:59:59.000Z

    We study two-level systems (2LS) coupled at different points to a one-dimensional waveguide in which one end is open and the other is either open (infinite waveguide) or closed by a mirror (semi-infinite). Upon injection of two photons (corresponding to weak coherent driving), the resonance fluorescence and photon correlations are shaped by the effective qubit transition frequencies and decay rates, which are substantially modified by interference effects. In contrast to the well-known result in an infinite waveguide, photons reflected by a single 2LS coupled to a semi-infinite waveguide are initially bunched, a result that can be simply explained by stimulated emission. As the number of 2LS increases (up to 10 are considered here), rapid oscillations build up in the correlations that persist for a very long time. For instance, when the incoming photons are slightly detuned, the transmitted photons in the infinite waveguide are highly antibunched. On the other hand, upon resonant driving, incoherently reflected photons are mostly distributed within the photonic band gap and several sharp side peaks. These features can be explained by considering the poles of the single particle Green function in the Markovian regime combined with the time delay. Our calculation is not restricted to the Markovian regime, and we obtain several fully non-Markovian results. We show that a single 2LS in a semi-infinite waveguide can not be decoupled by placing it at the node of the photonic field, in contrast to recent results in the Markovian regime. Our results illustrate the complexities that ensue when several qubits are strongly coupled to a bus (the waveguide) as might happen in quantum information processing.

  5. Phonon-assisted robust and deterministic two-photon biexciton preparation in a quantum dot

    E-Print Network [OSTI]

    S. Bounouar; M. Müller; A. M. Barth; M. Glässl; V. M. Axt; P. Michler

    2014-08-29T23:59:59.000Z

    We investigate both experimentally and theoretically a simple yet more robust and flexible alternative to Rabi oscillation-type biexciton preparation protocols traditionally used for semiconductor quantum dots. The quantum dot is excited by a strong laser pulse positively detuned from the two-photon resonance yielding an on demand initialization of the biexciton state by making use of the phonon-induced thermalization of the photon dressed states. It is shown that for excitation pulses in the picosecond range, a stable and high fidelity of up to $f_{XX}=0.98\\pm 0.01$ is reached. Notably, the generated photons show similar coherence properties as measured in the resonant two-photon scheme. This protocol is a powerful tool for the control of complex solid state systems combining radiative cascades, entanglement and resonant cavity modes.

  6. Macro-coherent two photon and radiative neutrino pair emission

    E-Print Network [OSTI]

    M. Yoshimura; C. Ohae; A. Fukumi; K. Nakajima; I. Nakano; H. Nanjo; N. Sasao

    2008-05-14T23:59:59.000Z

    We discuss a possibility of detecting a coherent photon pair emission and related radiative neutrino pair emission from excited atoms. It is shown that atoms of lambda- and ladder-type three level system placed in a pencil-like cylinder give a back to back emission of two photons of equal energy $\\Delta/2$, sharply peaked with a width $\\propto $ 1/(target size) and well collimated along the cylinder axis. This process has a measurable rate $\\propto$ (target number density) $^2 \\times$ target volume, while a broader spectral feature of one-photon distribution separated by (mass sum of a neutrino pair)$^2/(2\\Delta)$ from the two photon peak may arise from radiative neutrino pair emission, with a much smaller rate.

  7. Surface states controlled broadband enhancement of two-photon absorption

    SciTech Connect (OSTI)

    Zhou, Zhiqiang; Lu, Changgui; Xu, Shuhong; Jiang, Yuan; Yun, Binfeng; Wang, Chunlei; Cui, Yiping, E-mail: cyp@seu.edu.cn [Advanced Photonics Center, School of Electronic Science and Engineering, Southeast University, Nanjing 210096 (China)] [Advanced Photonics Center, School of Electronic Science and Engineering, Southeast University, Nanjing 210096 (China)

    2013-12-02T23:59:59.000Z

    We demonstrate the controllable broadband enhancement of two-photon absorption in a wide spectral range from 710?nm to 960?nm by controlling the surface states of aqueous Co{sup 2+} doped CdTe quantum dots, which is consistent with the measurement results of surface potential and fluorescence decay. The enhancement can be tuned in the range between 1 and 1.7 by changing the dopant concentrations that determine the surface states.

  8. Externally triggered coherent two-photon emission from hydrogen molecules

    E-Print Network [OSTI]

    Yuki Miyamoto; Hideaki Hara; Takahiko Masuda; Noboru Sasao; Minoru Tanaka; Satoshi Uetake; Akihiro Yoshimi; Koji Yoshimura; Motohiko Yoshimura

    2015-05-28T23:59:59.000Z

    We report coherent enhancement of two-photon emission from the excited vibrational state of molecular hydrogen triggered by irradiating mid-infrared pulses externally. We previously observed the two-photon emission triggered by the internally generated fourth Stokes photons. By injecting independent mid-infrared pulses externally, it is possible to control experimental parameters and investigate the mechanism in more detail. In this article, we describe the two-photon emission using the external trigger pulses. Its spectrum and dependence on the energy and timing of the trigger pulse are presented along with numerical simulations based on the Maxwell-Bloch equations. The measured number of emitted photons is 6 10^11 photons/pulse and the resulting enhancement factor from the spontaneous emission is more than 10^18. This value is three orders of magnitude higher than that of the previous experiment. External control of emission process is expected to be essential for observation of weaker process of radiative emission of neutrino pair.

  9. The Nonlocal Pancharatnam Phase in Two-Photon Interferometry

    E-Print Network [OSTI]

    Poonam Mehta; Joseph Samuel; Supurna Sinha

    2010-09-03T23:59:59.000Z

    We propose a polarised intensity interferometry experiment, which measures the nonlocal Pancharatnam phase acquired by a pair of Hanbury Brown-Twiss photons. The setup involves two polarised thermal sources illuminating two polarised detectors. Varying the relative polarisation angle of the detectors introduces a two photon geometric phase. Local measurements at either detector do not reveal the effects of the phase, which is an optical analog of the multiparticle Aharonov-Bohm effect. The geometric phase sheds light on the three slit experiment and suggests ways of tuning entanglement.

  10. Optimization of Two-photon Excited Fluorescence Enhancement between Tunable and Broadband Femtosecond Laser Pulse Excitations

    E-Print Network [OSTI]

    Wang, Chao

    2012-02-14T23:59:59.000Z

    This project explores optimization of two-photon excited fluorescence (TPEF) enhancement between tunable narrowband and un-tuned broadband femtosecond (fs) laser pulse excitations for two-photon microscopy (TPM). The research is conducted...

  11. Attosecond two-photon interferometry for doubly excited states of helium

    E-Print Network [OSTI]

    J. Feist; S. Nagele; C. Ticknor; B. I. Schneider; L. A. Collins; J. Burgdörfer

    2011-04-19T23:59:59.000Z

    We show that the correlation dynamics in coherently excited doubly excited resonances of helium can be followed in real time by two-photon interferometry. This approach promises to map the evolution of the two-electron wave packet onto experimentally easily accessible non-coincident single electron spectra. We analyze the interferometric signal in terms of a semi-analytical model which is validated by a numerical solution of the time-dependent two-electron Schr\\"odinger equation in its full dimensionality.

  12. Two-Photon Exchange E#27;ffects in Elastic Electron-Proton Scattering

    SciTech Connect (OSTI)

    Johnson, Myriam James [Argonne National Laboratory

    2013-08-01T23:59:59.000Z

    Two methods, Rosenbluth separation and polarization transfer, can be used to extract the proton form factor ratio #22;mu_p G_Ep/G_Mp, but they do not yield the same results. It is thought that the disagreement is due to two photon exchange corrections to the #27;differential cross sections. High precision proton Rosenbluth extractions were carried out at 102 kinematics points spanning 16 values of momentum transfer Q^2, from 0.40 to 5.76 GeV^2. Reduced cross sections were found to 1.1% or better for Q^2 less than 3 GeV^2, increasing to 4% at 5.76 GeV^2. The form factor ratios were determined to 1:5-3% for Q2 < 1.5 GeV^2, increasing to 9% by 3 GeV^2 and rapidly above. Our data agrees with prior Rosenbluth, improving upon it the 1.0 - 2.0 GeV^2 range to conclusively show a separation from polarization transfer where it had not been certain before. In addition, reduced cross sections at each Q^2 were tested for nonlinearity in the angular variable. Such a departure from linearity would be a signature of two photon exchange effects, and prior data had not been #30;sufficiently precise to show nonzero curvature. Our data begins to hint at negative curvature but does not yet show a significant departure from zero.

  13. Electron correlation in two-photon double ionization of helium from attosecond to FEL pulses

    SciTech Connect (OSTI)

    Collins, Lee [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    We investigate the role of electron correlation in the two-photon double ionization of helium for ultrashort pulses in the extreme ultraviolet (XUV) regime with durations ranging from a hundred attoseconds to a few femtoseconds. We perform time-dependent ab initio calculations for pulses with mean frequencies in the so-called 'sequential' regime ({Dirac_h}{omega} > 54.4 eV). Electron correlation induced by the time correlation between emission events manifests itself in the angular distribution of the ejected electrons, which strongly depends on the energy sharing between them. We show that for ultrashort pulses two-photon double ionization probabilities scale non-uniformly with pulse duration depending on the energy sharing between the electrons. Most interestingly we find evidence for an interference between direct ('nonsequential') and indirect ('sequential') double photoionization with intermediate shake-up states, the strength of which is controlled by the pulse duration. This observation may provide a route towards measuring the pulse duration of x-ray free-electron laser (XFEL) pulses.

  14. Analysis of Enhanced Two-Photon Absorption in Tapered Optical Fibers

    E-Print Network [OSTI]

    Hao You; S. M. Hendrickson; J. D. Franson

    2008-09-30T23:59:59.000Z

    We analyze the rate of two-photon absorption in tapered optical fibers with diameters less than the wavelength of the incident light. The rate of two-photon absorption is shown to be enhanced due to the small mode volume of the tapered fiber and the relatively large overlap of the evanescent field with an atomic vapor that surrounds the tapered region. The two-photon absorption rate is optimized as a function of the diameter of the tapered region.

  15. Fast, High Fidelity Quantum Dot Spin Initialization without a Strong Magnetic Field by Two-Photon Processes

    E-Print Network [OSTI]

    Arka Majumdar; Ziliang Lin; Andrei Faraon; Jelena Vuckovic

    2009-07-20T23:59:59.000Z

    We describe a proposal for fast electron spin initialization in a negatively charged quantum dot coupled to a microcavity without the need for a strong magnetic field. We employ two-photon excitation to access trion states that are spin forbidden by one-photon excitation. Our simulation shows a maximum initialization speed of 1.3 GHz and maximum fidelity of 99.7% with realistic system parameters.

  16. Two-photon photovoltaic effect in gallium arsenide Jeff Chiles,1

    E-Print Network [OSTI]

    Fathpour, Sasan

    Two-photon photovoltaic effect in gallium arsenide Jichi Ma,1 Jeff Chiles,1 Yagya D. Sharma,2 214669); published September 4, 2014 The two-photon photovoltaic effect is demonstrated in gallium; (230.0250) Optoelectronics; (040.5350) Photovoltaic; (130.4310) Nonlinear. http://dx.doi.org/10.1364/OL

  17. Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons

    E-Print Network [OSTI]

    Tsien, Roger Y.

    Video-Rate Scanning Two-Photon Excitation Fluorescence Microscopy and Ratio Imaging with Cameleons ABSTRACT A video-rate (30 frames/s) scanning two-photon excitation microscope has been successfully tested 690 to 1050 nm, prechirper optics for laser pulse-width compression, resonant galvanometer for video

  18. Universal features in sequential and nonsequential two-photon double ionization of helium

    E-Print Network [OSTI]

    R. Pazourek; J. Feist; S. Nagele; E. Persson; B. I. Schneider; L. A. Collins; J. Burgörfer

    2011-02-08T23:59:59.000Z

    We analyze two-photon double ionization of helium in both the nonsequential and sequential regime. We show that the energy spacing between the two emitted electrons provides the key parameter that controls both the energy and the angular distribution and reveals the universal features present in both the nonsequential and sequential regime. This universality, i.e., independence of photon energy, is a manifestation of the continuity across the threshold for sequential double ionization. For all photon energies, the energy distribution can be described by a universal shape function that contains only the spectral and temporal information entering second-order time-dependent perturbation theory. Angular correlations and distributions are found to be more sensitive to the photon energy. In particular, shake-up interferences have a large effect on the angular distribution. Energy spectra, angular distributions parameterized by the anisotropy parameters, and total cross sections presented in this paper are obtained by fully correlated time-dependent ab initio calculations.

  19. Partial angular coherence and the angular Schmidt spectrum of entangled two-photon fields

    SciTech Connect (OSTI)

    Jha, Anand Kumar; Boyd, Robert W. [Institute of Optics, University of Rochester, Rochester, New York 14627 (United States); Agarwal, Girish S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

    2011-12-15T23:59:59.000Z

    We study partially coherent fields that have a coherent-mode representation in the orbital-angular-momentum-mode basis. For such fields, we introduce the concepts of the angular coherence function and the coherence angle. Such fields are naturally produced by the process of parametric down-conversion--a second-order nonlinear optical process in which a pump photon breaks up into two entangled photons, known as the signal and idler photons. We show that the angular coherence functions of the signal and idler fields are directly related to the angular Schmidt (spiral) spectrum of the down-converted two-photon field and thus that the angular Schmidt spectrum can be measured directly by measuring the angular coherence function of either the signal or the idler field, without requiring coincidence detection.

  20. Absolute frequency measurement of an SF6 two-photon line using a femtosecond optical comb and sum-frequency

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Absolute frequency measurement of an SF6 two-photon line using a femtosecond optical comb and sum laser. The absolute frequency of a CO2 laser stabilized onto an SF6 two-photon line has been measured

  1. Two-photon decay of light scalars: a comparison of tetraquark and quarkonium assignments

    E-Print Network [OSTI]

    Francesco Giacosa

    2009-03-31T23:59:59.000Z

    Two-photon decays of light scalar mesons are discussed within the quarkonium and tetraquark asignements: in both cases the decay rate of the sigma resonances turns out to be smaller than 1 keV.

  2. Two photon luminescence from quantum dots using broad and narrowband ultrafast laser pulses

    E-Print Network [OSTI]

    Balasubramanian, Haribhaskar

    2009-05-15T23:59:59.000Z

    Nonlinear optical microscopy (NLOM) offers many advantages when imaging intact biological samples. By using ultrafast lasers in the near infrared and two photon excitation (TPE), signal production is limited to the focal volume and provides...

  3. Two photon luminescence from quantum dots using broad and narrowband ultrafast laser pulses 

    E-Print Network [OSTI]

    Balasubramanian, Haribhaskar

    2009-05-15T23:59:59.000Z

    Nonlinear optical microscopy (NLOM) offers many advantages when imaging intact biological samples. By using ultrafast lasers in the near infrared and two photon excitation (TPE), signal production is limited to the focal volume and provides...

  4. Two photon luminescence from quantum dots using broad and narrowband ultrafast laser pulses 

    E-Print Network [OSTI]

    Balasubramanian, Haribhaskar

    2008-10-10T23:59:59.000Z

    Nonlinear optical microscopy (NLOM) offers many advantages when imaging intact biological samples. By using ultrafast lasers in the near infrared and two photon excitation (TPE), signal production is limited to the focal volume and provides...

  5. Synthesis of Photoresponsive Dual NIR Two-Photon Absorptive [60]Fullerene Triads and Tetrads

    E-Print Network [OSTI]

    Jeon, Seaho

    Broadband nonlinear optical (NLO) organic nanostructures exhibiting both ultrafast photoresponse and a large cross-section of two-photon absorption throughout a wide NIR spectrum may make them suitable for use as nonlinear ...

  6. Development of high-speed two-photon microscopy for biological and medical applications

    E-Print Network [OSTI]

    Kim, Ki Hean

    2005-01-01T23:59:59.000Z

    Two-photon microscopy (TPM) is one of the most powerful microscopic technologies for in-vivo 3D tissue imaging up to a few hundred micrometers. It has been finding important applications in neuronal imaging, tumor physiology ...

  7. Triple Differential Cross sections and Nuclear Recoil in Two-Photon Double Ionization of Helium

    E-Print Network [OSTI]

    Horner, Daniel A.

    2008-01-01T23:59:59.000Z

    Two-Photon Double Ionization of Helium D. A. Horner, 1 C. W.photon double ionization of helium are calculated using theDouble ionization of the helium atom by two XUV photons in

  8. Enhanced Two-Photon Absorption Using Entangled States and Small Mode Volumes

    E-Print Network [OSTI]

    Hao You; S. M. Hendrickson; J. D. Franson

    2009-07-13T23:59:59.000Z

    We calculate the rate of two-photon absorption for frequency entangled photons in a tapered optical fiber whose diameter is comparable to the wavelength of the light. The confinement of the electric field in the transverse direction increases the intensity associated with a single photon, while the two-photon absorption rate is further enhanced by the fact that the sum of the frequencies of the two photons is on resonance with the upper atomic state, even though each photon has a relatively broad linewidth. As a result, the photons are effectively confined in all three dimensions and the two-photon absorption rate for frequency-entangled photons in a tapered fiber was found to be comparable to that for unentangled photons in a microcavity with a small mode volume.

  9. Two photon luminescence from quantum dots using broad and narrowband ultrafast laser pulses

    E-Print Network [OSTI]

    Balasubramanian, Haribhaskar

    2008-10-10T23:59:59.000Z

    TWO PHOTON LUMINESCENCE FROM QUANTUM DOTS USING BROAD AND NARROWBAND ULTRAFAST LASER PULSES A Thesis by HARIBHASKAR BALASUBRAMANIAN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of MASTER OF SCIENCE December 2007 Major Subject: Biomedical Engineering TWO PHOTON LUMINESCENCE FROM QUANTUM DOTS USING BROAD AND NARROWBAND ULTRAFAST LASER PULSES A Thesis by HARIBHASKAR...

  10. Investigating two-photon double ionization of D{sub 2} by XUV-pump-XUV-probe experiments

    SciTech Connect (OSTI)

    Jiang, Y. H.; Kurka, M.; Kuehnel, K. U.; Toppin, M.; Schroeter, C. D.; Moshammer, R. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Rudenko, A.; Foucar, L. [Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Perez-Torres, J. F.; Plesiat, E.; Morales, F.; Martin, F. [Departamento de Quimica C-9, Universidad Autonoma de Madrid, 28049 Madrid (Spain); Herrwerth, O.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Jahnke, T.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Sanz-Vicario, J. L. [Instituto de Fisica, Universidad de Antioquia, Medellin (Colombia); Tilborg, J. van; Belkacem, A. [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-05-15T23:59:59.000Z

    We used a split-mirror setup attached to a reaction microscope at the free-electron laser in Hamburg (FLASH) to perform an XUV-pump-XUV-probe experiment by tracing the ultrafast nuclear wave-packet motion in the D{sub 2}{sup +}(1s{sigma}{sub g}) with <10 fs time resolution. Comparison with time-dependent calculations shows excellent agreement with the measured vibrational period of 22{+-}4 fs in D{sub 2}{sup +}, points to the importance of accurately knowing the internuclear distance-dependent ionization probability, and paves the way to control sequential and nonsequential two-photon double-ionization contributions.

  11. Direct measurement of the biphoton Wigner function through two-photon interference

    E-Print Network [OSTI]

    Tom Douce; Andreas Eckstein; Stephen P. Walborn; Antonio Z. Khoury; Sara Ducci; Arne Keller; Thomas Coudreau; Pérola Milman

    2013-09-26T23:59:59.000Z

    The Hong-Ou-Mandel (HOM) experiment was a benchmark in quantum optics, evidencing the quantum nature of the photon. In order to go deeper, and obtain the complete information about the quantum state of a system, for instance, composed by photons, the direct measurement or reconstruction of the Wigner function or other quasi--probability distribution in phase space is necessary. In the present paper, we show that a simple modification in the well-known HOM experiment provides the direct measurement of the Wigner function. We apply our results to a widely used quantum optics system, consisting of the biphoton generated in the parametric down conversion process. In this approach, a negative value of the Wigner function is a sufficient condition for non-gaussian entanglement between two photons. In the general case, the Wigner function provides all the required information to infer entanglement using well known necessary and sufficient criteria. We analyze our results using two examples of parametric down conversion processes taken from recent experiments. The present work offers a new vision of the HOM experiment that further develops its possibilities to realize fundamental tests of quantum mechanics involving decoherence and entanglement using simple optical set-ups.

  12. Enhanced-locality fiber-optic two-photon-fluorescence live-brain interrogation

    SciTech Connect (OSTI)

    Fedotov, I. V.; Doronina-Amitonova, L. V. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Kurchatov Institute National Research Center, Moscow (Russian Federation); Sidorov-Biryukov, D. A.; Fedotov, A. B. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Anokhin, K. V. [Kurchatov Institute National Research Center, Moscow (Russian Federation); P.K. Anokhin Institute of Normal Physiology, Russian Academy of Medical Sciences, Moscow (Russian Federation); Kilin, S. Ya. [B.I. Stepanov Institute of Physics, National Academy of Sciences of Belarus, Minsk (Belarus); Sakoda, K. [National Institute for Materials Science, 1-1 Namiki, Tsukuba 305-0044 (Japan); Zheltikov, A. M. [International Laser Center, Physics Department, M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation); Russian Quantum Center, ul. Novaya 100, Skolkovo, Moscow Region 1430125 (Russian Federation); Department of Physics and Astronomy, Texas A and M University, College Station, Texas 77843 (United States); Center of Photochemistry, Russian Academy of Sciences, ul. Novatorov 7a, Moscow 117421 (Russian Federation)

    2014-02-24T23:59:59.000Z

    Two-photon excitation is shown to substantially enhance the locality of fiber-based optical interrogation of strongly scattering biotissues. In our experiments, a high-numerical-aperture, large-core-are fiber probe is used to deliver the 200-fs output of a 100-MHz mode-locked ytterbium fiber laser to samples of live mouse brain, induce two-photon fluorescence of nitrogen–vacancy centers in diamond markers in brain sample. Fiber probes with a high numerical aperture and a large core area are shown to enable locality enhancement in fiber-laser–fiber-probe two-photon brain excitation and interrogation without sacrificing the efficiency of fluorescence response collection.

  13. Amplitude and phase modulation of time-energy entangled two-photon states

    E-Print Network [OSTI]

    F. Zäh; M. Halder; T. Feurer

    2009-01-22T23:59:59.000Z

    We experimentally demonstrate amplitude and phase modulation of a time-energy entangled two-photon wave function. The entangled photons are produced by spontaneous parametric down-conversion, spectrally dispersed in an prism compressor, modulated in amplitude and/or phase, and detected in coincidence by sum-frequency generation. First, we present a Fourier optical analysis of the optical setup yielding an analytic expression for the resulting field distribution at the exit plane of the shaping apparatus. We then introduce amplitude and/or phase shaping and present results which can only be obtained through a combination of the two. Specifically, we use a shaper-based interferometer to measure the two-photon interference of an almost bandwidth-limited two-photon wave function.

  14. Global analysis of proton elastic form factor data with two-photon exchange corrections

    SciTech Connect (OSTI)

    J. Arrington; W. Melnitchouk; J. A. Tjon

    2007-09-01T23:59:59.000Z

    We use the world's data on elastic electron-proton scattering and calculations of two-photon exchange effects to extract corrected values of the proton's electric and magnetic form factors over the full Q^2 range of the existing data. Our analysis combines the corrected Rosenbluth cross section and polarization transfer data, and is the first extraction of G_Ep and G_Mp including explicit two-photon exchange corrections and their associated uncertainties. In addition, we examine the angular dependence of the corrected cross sections, and discuss the possible nonlinearities of the cross section as a function of epsilon.

  15. Mapping of two-photon luminescence amplification in zinc-oxide microstructures

    SciTech Connect (OSTI)

    Semin, S. V., E-mail: sv_semin@mail.ru; Sherstyuk, N. E.; Mishina, E. D. [Moscow State Technical University of Radio Engineering, Electronics and Automation (Russian Federation); Gherman, C.; Kulyuk, L. [Academy of Sciences of Moldova, Institute of Applied Physics (Moldova, Republic of); Rasing, Th. [Radboud University Nijmegen, Institute for Molecules and Materials (Netherlands); Peng, L.-H. [National Taiwan University, Department of Electrical Engineering and Institute of Photonics and Optoelectronics (China)

    2012-03-15T23:59:59.000Z

    The mapping of two-photon excited luminescence in aggregations of free-standing zinc oxide microrods has been carried out at room temperature. Two-photon luminescence spectra in the excitonic region for individual microrods have been recorded. The luminescence intensity exhibits a power-law dependence on the optical pump power with the exponent n > 2. This fact, along with the existence of a threshold power above which the dependence in the exciton region deviates from a quadratic one, indicates the onset of light amplification in individual ZnO microrods and the conditions preceding laser oscillation.

  16. Engineering atom-atom thermal entanglement via two-photon process

    E-Print Network [OSTI]

    Y. Q. Guo; L. Zhou; H. S. Song

    2005-09-21T23:59:59.000Z

    We study the system that two atoms simultaneously interact with a single-mode thermal field via different couplings and different spontaneous emission rates when two-photon process is involved. It is found that we indeed can employ the different couplings to produce the atom-atom thermal entanglement in two-photon process. The different atomic spontaneous emission rates are also utilizable in generating thermal entanglement. We also investigate the effect of the cavity leakage. To the initial atomic state $|ee> ,$a slight leakage can relieve the restriction of interaction time and we can obtain a large and steady entanglement.

  17. Two-Photon 2s1s Transitions during Recombination of Hydrogen in the Universe

    E-Print Network [OSTI]

    E. E. Kholupenko; A. V. Ivanchik

    2006-11-13T23:59:59.000Z

    Based on the standard cosmological model, we calculate the correction to the rate of two-photon 2s1s transitions in the hydrogen atom under primordial hydrogen plasma recombination conditions that arises when the induced transitions under equilibrium background radiation with a blackbody spectrum and plasma recombination radiation are taken into account.

  18. Measurement of Electron Beam Polarization from Unstrained Bulk GaAs via Two Photon Photoemission

    E-Print Network [OSTI]

    Gay, Timothy J.

    the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab, where the polarized electron beamMeasurement of Electron Beam Polarization from Unstrained Bulk GaAs via Two Photon Photoemission Collections Journals About Contact us My IOPscience #12;Measurement of Electron Beam Polarization from

  19. Ris-PhD-10(EN) The development of efficient two-photon

    E-Print Network [OSTI]

    diagram illustrating the photosensitized generation of singlet oxygen and an example of a sensitizer that these biologically friendly molecules could not be brought to generate singlet oxygen in a two-photon irradiation 5 1.1 The interest in singlet oxygen 5 1.2 Generating singlet oxygen 6 1.3 Singlet and triplet

  20. Ultrafast Third Harmonic Micro-spectroscopy Reveals a Two-Photon Resonance in Human Hemoglobin

    E-Print Network [OSTI]

    Kleinfeld, David

    Ultrafast Third Harmonic Micro-spectroscopy Reveals a Two-Photon Resonance in Human Hemoglobin G Golden, CO 80401 Abstract The recently developed technique of ultrafast third harmonic generation (THG states in physiological solutions of human hemoglobin. Keywords: Third Harmonic Generation, Micro

  1. Europium-Doped TiO2 Hollow Nanoshells: Two-Photon Imaging of Cell Binding

    E-Print Network [OSTI]

    Kummel, Andrew C.

    Europium-Doped TiO2 Hollow Nanoshells: Two-Photon Imaging of Cell Binding Sergio Sandoval,,,§ Jian method to fabricate luminescent monodisperse 200 nm europium-doped hollow TiO2 nanoshell (NS) particles-functionalized polystyrene beads were used as templates, and the porous walls of europium-doped titania nanoshells were

  2. Two-Photon Intravital Imaging of Lungs during Anthrax Infection Reveals Long-Lasting Macrophage-Dendritic Cell Contacts

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Two-Photon Intravital Imaging of Lungs during Anthrax Infection Reveals Long-Lasting Macrophage ; Ecole du Val-de-Grâce, Paris, Francee The dynamics of the lung immune system at the microscopic level. In this study, we developed an improved intravital method for two-photon lung imaging uniquely based

  3. Radiative recombination and ultralong exciton photoluminescence lifetime in GaN freestanding film via two-photon excitation

    E-Print Network [OSTI]

    Radiative recombination and ultralong exciton photoluminescence lifetime in GaN freestanding film of a freestanding GaN film using one-photon and two-photon excitations to demonstrate the dramatic difference at 295 K is observed from a GaN freestanding film using two-photon excitation, whereas less than 100 ps

  4. Local Two-Photon Couplings and the J=0 Fixed Pole in Real and Virtual Compton Scattering

    E-Print Network [OSTI]

    Stanley J. Brodsky; Felipe J. Llanes-Estrada; Adam P. Szczepaniak

    2008-12-02T23:59:59.000Z

    The local coupling of two photons to the fundamental quark currents of a hadron gives an energy-independent contribution to the Compton amplitude proportional to the charge squared of the struck quark, a contribution which has no analog in hadron scattering reactions. We show that this local contribution has a real phase and is universal, giving the same contribution for real or virtual Compton scattering for any photon virtuality and skewness at fixed momentum transfer squared t. The t-dependence of this J=0 fixed Regge pole is parameterized by a yet unmeasured even charge-conjugation form factor of the target nucleon. The t=0 limit gives an important constraint on the dependence of the nucleon mass on the quark mass through the Weisberger relation. We discuss how this 1/x form factor can be extracted from high energy deeply virtual Compton scattering and examine predictions given by models of the H generalized parton distribution.

  5. Measurement of electron beam polarization from unstrained GaAs via two-photon photoemission

    SciTech Connect (OSTI)

    McCarter, James L. [Univ. of Virginia, Charlottesville, VA (United States); Afanasev, A. [George Washington Univ., Washingon, DC (United States); Gay, T. J. [Univ. of Nebraska, Lincoln, NE (United States); Hansknecht, John C. [JLAB, Newport News, VA (United States); Kechiantz, A. [George Washington Univ., Washingon, DC (United States); Poelker, B. Matthew [JLAB, Newport News, VA (United States)

    2014-02-01T23:59:59.000Z

    Two-photon absorption of 1560 nm light was used to generate polarized electron beams from unstrained GaAs photocathodes of varying thickness: 625 {mu}m, 0.32 {mu}m, and 0.18 {mu}m. For each photocathode, the degree of spin polarization of the photoemitted beam was less than 50%, contradicting earlier predictions based on simple quantum mechanical selection rules for spherically-symmetric systems but consistent with the more sophisticated model of Bhat et al. (Phys. Rev. B 71 (2005) 035209). Polarization via two-photon absorption was the highest from the thinnest photocathode sample and comparable to that obtained via one-photon absorption (using 778 nm light), with values 40.3 +- 1.0% and 42.6 +- 1.0%, respectively.

  6. Adiabatic rapid passage two-photon excitation of a Rydberg atom

    E-Print Network [OSTI]

    Kuznetsova, Elena; Malinovskaya, Svetlana A

    2015-01-01T23:59:59.000Z

    We considered the two-photon adiabatic rapid passage excitation of a single atom from the ground to a Rydberg state. Three schemes were analyzed: both pump and Stokes fields chirped and pulsed, only the pump field is chirped, and only the pump field is pulsed and chirped while the Stokes field is continuous wave (CW). In all three cases high transfer efficiencies $>99\\%$ were achieved for the experimentally realizable Rabi frequencies and the pulse durations of the fields.

  7. Stimulated emission of two photons in parametric amplification and its interpretation as multi-photon interference

    E-Print Network [OSTI]

    F. W. Sun; B. H. Liu; Y. X. Gong; Y. F. Huang; Z. Y. Ou; G. C. Guo

    2007-02-06T23:59:59.000Z

    Stimulated emission of two photons is observed experimentally in the parametric amplification process and is compared to a three-photon interference scheme. We find that the underlying physics of stimulated emission is simply the constructive interference due to photon indistinguishability. So the observed signal enhancement upon the input of photons is a result of multi-photon interference of the input photons and the otherwise spontaneously emitted photon from the amplifier.

  8. Two-photon excitation spectrum of light-harvesting complex II and fluorescence upconversion after one- and two-photon excitation of the carotenoids

    SciTech Connect (OSTI)

    Walla, P.J.; Yom, J.; Krueger, B.P.; Fleming, G.R.

    2000-05-18T23:59:59.000Z

    The two-photon excitation (TPE) spectrum of light-harvesting complex II (LHC II) has been measured in the spectral region of 1,000--1,600 nm, corresponding to one-photon wavelengths of 500--800 nm. The authors observed a band with an origin at {approximately}2 x 660 nm (ca. 15,100 {+-} 300 cm{sup {minus}1}) and a maximum at {approximately}2 x 600 nm. The line shape and origin of this band strongly suggest that the observed signal is due to the two-photon-allowed S{sub 1} state of the energy-transferring carotenoids (Car ) in LHC II. The authors also report the time dependence of the upconverted chlorophyll (Chl) fluorescence after TPE at the maximum of the observed band. Surprisingly, a fast rise of 250 {+-} 50 fs followed by a multiexponential decay on the picosecond time scale was observed. This result provides strong indication that there is a fast energy transfer even from the dipole-forbidden Car S{sub 1} state to the Chl's. The sub picosecond energy transfer from the Car S{sub 1} state is likely a consequence of the large number of energy-accepting Chls in van der Waals contact with the central Car's in LHC II. They also present upconversion data of the Car S{sub 2}, Chl a, and Chl b fluorescence observed after one-photon excitation into the dipole-allowed Car S{sub 2} state. The lifetime of the Car S{sub 2} state is {approximately}120 {+-} 30 fs. With the observed time constants they are able to calculate quantum yields for the different possible pathways contributing to the overall Car to Chl energy transfer in LHC II.

  9. Transverse target spin asymmetry in inclusive DIS with two-photon exchange

    SciTech Connect (OSTI)

    Andrei Afanasev; Mark Strikman; Christian Weiss

    2007-09-06T23:59:59.000Z

    We study the transverse target spin dependence of the cross section for the inclusive electron-nucleon scattering with unpolarized beam. Such dependence is absent in the one-photon exchange approximation (Christ-Lee theorem) and arises only in higher orders of the QED expansion, from the interference of one-photon and absorptive two-photon exchange amplitudes as well as from real photon emission (bremsstrahlung). We demonstrate that the transverse spin-dependent two-photon exchange cross section is free of QED infrared and collinear divergences. We argue that in DIS kinematics the transverse spin dependence should be governed by a "parton-like" mechanism in which the two-photon exchange couples mainly to a single quark. We calculate the normal spin asymmetry in an approximation where the dominant contribution arises from quark helicity flip due to interactions with non-perturbative vacuum fields (constituent quark picture) and is proportional to the quark transversity distribution in the nucleon. Such helicity-flip processes are not significantly Sudakov-suppressed if the infrared scale for gluon emission in the photon-quark subprocess is of the order of the chiral symmetry breaking scale, mu^2_chiral>>Lambda^2_QCD. We estimate the asymmetry in the kinematics of the planned Jefferson Lab Hall A experiment to be of the order 10^-4, with different sign for proton and neutron. We also comment on the spin dependence in the limit of soft high-energy scattering.

  10. Calculation of the spatial resolution in two-photon absorption spectroscopy applied to plasma diagnosis

    SciTech Connect (OSTI)

    Garcia-Lechuga, M. [Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, 47011-Valladolid (Spain); Laser Processing Group, Instituto de Óptica “Daza de Valdés,” CSIC, 28006-Madrid (Spain); Fuentes, L. M. [Departamento de Física Aplicada, Universidad de Valladolid, 47011-Valladolid (Spain); Grützmacher, K.; Pérez, C., E-mail: concha@opt.uva.es; Rosa, M. I. de la [Departamento de Física Teórica, Atómica y Óptica, Universidad de Valladolid, 47011-Valladolid (Spain)

    2014-10-07T23:59:59.000Z

    We report a detailed characterization of the spatial resolution provided by two-photon absorption spectroscopy suited for plasma diagnosis via the 1S-2S transition of atomic hydrogen for optogalvanic detection and laser induced fluorescence (LIF). A precise knowledge of the spatial resolution is crucial for a correct interpretation of measurements, if the plasma parameters to be analysed undergo strong spatial variations. The present study is based on a novel approach which provides a reliable and realistic determination of the spatial resolution. Measured irradiance distribution of laser beam waists in the overlap volume, provided by a high resolution UV camera, are employed to resolve coupled rate equations accounting for two-photon excitation, fluorescence decay and ionization. The resulting three-dimensional yield distributions reveal in detail the spatial resolution for optogalvanic and LIF detection and related saturation due to depletion. Two-photon absorption profiles broader than the Fourier transform-limited laser bandwidth are also incorporated in the calculations. The approach allows an accurate analysis of the spatial resolution present in recent and future measurements.

  11. Two-photon widths of the {chi}{sub cJ} states of charmonium

    SciTech Connect (OSTI)

    Ecklund, K. M. [State University of New York at Buffalo, Buffalo, New York 14260 (United States); Love, W.; Savinov, V. [University of Pittsburgh, Pittsburgh, Pennsylvania 15260 (United States); Lopez, A.; Mendez, H.; Ramirez, J. [University of Puerto Rico, Mayaguez, Puerto Rico 00681 (Puerto Rico); Ge, J. Y.; Miller, D. H.; Shipsey, I. P. J.; Xin, B. [Purdue University, West Lafayette, Indiana 47907 (United States); Adams, G. S.; Anderson, M.; Cummings, J. P.; Danko, I.; Hu, D.; Moziak, B.; Napolitano, J. [Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); He, Q.; Insler, J.; Muramatsu, H. [University of Rochester, Rochester, New York 14627 (United States)] (and others)

    2008-11-01T23:59:59.000Z

    Using a data sample of 24.5x10{sup 6} {psi}(2S) the reactions {psi}(2S){yields}{gamma}{chi}{sub cJ}, {chi}{sub cJ}{yields}{gamma}{gamma} have been studied for the first time to determine the two-photon widths of the {chi}{sub cJ} states of charmonium in their decay into two photons. The measured quantities are B({psi}(2S){yields}{gamma}{chi}{sub c0})xB({chi}{sub c0}{yields}{gamma}{gamma})=(2.17{+-}0.32{+-}0.10)x10{sup -5} and B({psi}(2S){yields}{gamma}{chi}{sub c2})xB({chi}{sub c2}{yields}{gamma}{gamma})=(2.68{+-}0.28{+-}0.15)x10{sup -5}. Using values for B({psi}(2S){yields}{gamma}{chi}{sub c0,c2}) and {gamma}({chi}{sub c0,c2}) from the literature the two-photon widths are derived to be {gamma}{sub {gamma}}{sub {gamma}}({chi}{sub c0})=(2.36{+-}0.35{+-}0.22) keV, {gamma}{sub {gamma}}{sub {gamma}}({chi}{sub c2})=(0.66{+-}0.07{+-}0.06) keV, and R{identical_to}{gamma}{sub {gamma}}{sub {gamma}}({chi}{sub c2})/{gamma}{sub {gamma}}{sub {gamma}}({chi}{sub c0})=0.278{+-}0.050{+-}0.036. The importance of the measurement of R is emphasized. For the forbidden transition, {chi}{sub c1}{yields}{gamma}{gamma}, an upper limit of {gamma}{sub {gamma}}{sub {gamma}}({chi}{sub c1})<0.03 keV is established.

  12. Polarization dependence of two-photon transition intensities in rare-earth doped crystals

    SciTech Connect (OSTI)

    Le Nguyen, An-Dien

    1996-05-01T23:59:59.000Z

    A polarization dependence technique has been developed as a tool to investigate phonon scattering (PS), electronic Raman scattering (ERS), and two-photon absorption (TPA) transition intensities in vanadate and phosphate crystals. A general theory for the polarization dependence (PD) of two-photon transition intensities has been given. Expressions for the polarization dependent behavior of two-photon transition intensities have been tabulated for the 32 crystallographic point groups. When the wavefunctions for the initial and final states of a rare-earth doped in crystals are known, explicit PD expressions with no unknown parameters can be obtained. A spectroscopic method for measuring and interpreting phonon and ERS intensities has been developed to study PrVO{sub 4}, NdVO{sub 4}, ErVO{sub 4}, and TmVO{sub 4} crystals. Relative phonon intensities with the polarization of the incident and scattered light arbitrarily varied were accurately predicted and subsequently used for alignment and calibration in ERS measurements in these systems for the first time. Since ERS and PS intensities generally follow different polarization curves as a function of polar angles, the two can be uniquely identified by comparing their respective polarization behavior. The most crucial application of the technique in ERS spectroscopy is the establishment of a stringent test for the Axe theory. For the first time, the F{sub 1}/F{sub 2} ratio extracted from the experimental fits of the ERS intensities were compared with those predicted by theories which include both the second- and third-order contributions. Relatively good agreement between the fitted values of F{sub 1}/F{sub 2} and the predicted values using the second-order theory has been found.

  13. Two-photon polarization data storage in bacteriorhodopsin films and its potential use in security applications

    SciTech Connect (OSTI)

    Imhof, Martin; Hampp, Norbert, E-mail: hampp@staff.uni-marburg.de [Department of Chemistry, Material Sciences Center, University of Marburg, Hans-Meerwein-Str., D-35032 Marburg (Germany); Rhinow, Daniel [Max-Planck-Institute of Biophysics, Max-von-Laue-Straße 3, D-60438 Frankfurt (Germany)

    2014-02-24T23:59:59.000Z

    Bacteriorhodopsin (BR) films allow write-once-read-many recording of polarization data by a two-photon-absorption (TPA) process. The optical changes in BR films induced by the TPA recording were measured and the Müller matrix of a BR film was determined. A potential application of BR films in security technology is shown. Polarization data can be angle-selective retrieved with high signal-to-noise ratio. The BR film does not only carry optical information but serves also as a linear polarizer. This enables that polarization features recorded in BR films may be retrieved by merely using polarized light from a mobile phone display.

  14. TPEcalc: a program for calculation of two-photon exchange amplitudes

    E-Print Network [OSTI]

    Dmitry Borisyuk; Alexander Kobushkin

    2015-06-03T23:59:59.000Z

    TPEcalc is a C++ program for calculation of two-photon exchange (TPE) amplitudes in elastic electron-hadron scattering, based on the dispersion method. It is a command-line tool which accepts kinematical parameters (Q^2 and epsilon) as input and returns TPE amplitudes. It can do calculations for proton, neutron and pion targets. Any spin 1/2+ or spin 0- target is supported, if the user supplies all necessary form factor parameterizations. This paper describes how to use TPEcalc and outlines underlying theory. The program source code can be downloaded from http://tpe.bitp.kiev.ua/

  15. High-Sensitivity Two-Photon Spectroscopy in a Dark Optical Trap, based on Electron Shelving

    E-Print Network [OSTI]

    Khaykovich, B; Baluschev, S; Fathi, D; Davidson, N E

    1999-01-01T23:59:59.000Z

    We propose a new spectroscopic method for measuring weak transitions in cold and trapped atoms, which exploits the long interaction times and tight confinement offered by dark optical traps together with an electron shelving technique to achieve extremely high sensitivity. We demonstrate our scheme by measuring a 5S_{1/2}-> 5D_{5/2} two-photon transition in cold Rb atoms trapped in a new single-beam dark optical trap, using an extremely weak probe laser power of 25 micro-Watt. We were able to measure transitions with as small excitation rate as 0.09 sec^(-1).

  16. Control of two-photon quantum walk in a complex multimode system by wavefront shaping

    E-Print Network [OSTI]

    Defienne, Hugo; Walmsley, Ian A; Smith, Brian J; Gigan, Sylvain

    2015-01-01T23:59:59.000Z

    Multi-photon interferences in complex multimode structures - quantum walks - are of both funda- mental and technological interest. They rely on the ability to design the complex network where the walk occurs. Here, we demonstrate the control of quantum walks of two indistinguishable photons in a complex linear system - a highly multimode fiber - by means of wavefront shaping techniques. Using the measured transmission matrix of the fiber, we demonstrate the ability to address arbitrary output modes of the two-photon speckle pattern, and simultaneous control of the quantum inter- ferences. This work provides a reconfigurable platform for multi-photon, multimode interference experiments and a route to high-dimensional quantum systems.

  17. Two-photon adiabatic passage in ultracold Rb interacting with a single nanosecond, chirped pulse

    E-Print Network [OSTI]

    Liu, Gengyuan

    2015-01-01T23:59:59.000Z

    A semiclassical, four-level model of a nanosecond, chirped pulse interacting with all optically accessible hyperfine states in the ultracold Rb atom is analyzed aiming at population inversion within $5S_{1/2}$ electronic state. The nature of two-photon adiabatic passage performed by such a single pulse having a bandwidth smaller than the hyperfine splitting of $5S_{1/2}$ state is investigated in the framework of the dressed state picture. It is shown that two dressed states are involved in the adiabatic dynamics of population inversion. The excited state manifold appeared to play an important mediating role in the mechanism of population transfer.

  18. Role of noise operators on two-photon correlations in an extended coherent Raman medium

    E-Print Network [OSTI]

    Ooi, C. H. Raymond; Zubairy, M. Suhail.

    2007-01-01T23:59:59.000Z

    Role of noise operators on two-photon correlations in an extended coherent Raman medium C. H. Raymond Ooi1,2,3,4,* and M. Suhail Zubairy3,5 1Department of Physics, Korea Advanced Institute of Science and Technology, Daejeon, 305-701 Korea 2Max... & Aerospace Engineering, Princeton University, New Jersey 08544, USA 5Texas A&M University at Qatar, Education City, P.O. Box 23874, Doha, Qatar #1;Received 8 January 2007; published 29 May 2007#2; An extended medium driven in a double Raman configuration...

  19. A stable frequency comb directly referenced to rubidium electromagnetically induced transparency and two-photon transitions

    SciTech Connect (OSTI)

    Hou, Dong; Wu, Jiutao; Zhang, Shuangyou; Ren, Quansheng; Zhang, Zhigang; Zhao, Jianye, E-mail: zhaojianye@pku.edu.cn [Department of Electronics, Peking University, Beijing, 100871 (China)

    2014-03-17T23:59:59.000Z

    We demonstrate an approach to create a stable erbium-fiber-based frequency comb at communication band by directly locking the combs to two rubidium atomic transitions resonances (electromagnetically induced transparency absorption and two-photon absorption), respectively. This approach directly transfers the precision and stability of the atomic transitions to the comb. With its distinguishing feature of compactness by removing the conventional octave-spanning spectrum and f-to-2f beating facilities and the ability to directly control the comb's frequency at the atomic transition frequency, this stable optical comb can be widely used in optical communication, frequency standard, and optical spectroscopy and microscopy.

  20. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

    SciTech Connect (OSTI)

    Johns, James E.

    2010-05-01T23:59:59.000Z

    Ultrafast angle-resolved two photon photoemission was used to study the dynamics and interfacial band structure of ultrathin films adsorbed onto Ag(111). Studies focused on the image potential state (IPS) in each system as a probe for measuring changes in electronic behavior in differing environments. The energetics and dynamics of the IPS at the toluene/Ag(111) interface are strongly dependent upon coverage. For a single monolayer, the first IPS is bound by 0.81 eV below the vacuum level and has a lifetime of 50 femtoseconds (fs). Further adsorption of toluene creates islands of toluene with an exposed wetting layer underneath. The IPS is then split into two peaks, one corresponding to the islands and one corresponding to the monolayer. The wetting layer IPS shows the same dynamics as the monolayer, while the lifetime of the islands increases exponentially with increasing thickness. Furthermore, the island IPS transitions from delocalized to localized within 500 fs, and electrons with larger parallel momenta decay much faster. Attempts were made using a stochastic model to extract the rates of localization and intraband cooling at differing momenta. In sexithiophene (6T) and dihexyl-sexithiophene (DH6T), the IPS was used as a probe to see if the nuclear motion of spectating side chains can interfere with molecular conduction. The energy and band mass of the IPS was measured for 6T and two geometries of DH6T on Ag(111). Electrons injected into the thicker coverages of DH6T grew exponentially heavier until they were completely localized by 230 fs, while those injected into 6T remained nearly free electron like. Based off of lifetime arguments and the density of defects, the most likely cause for the mass enhancement of the IPS in this system is small polaron formation caused by coupling of the electron to vibrations of the alkyl substituents. The energetic relaxation of the molecular adsorbate was also measured to be 20 meV/100 fs for the DH6T, and 0 meV/100 fs for the 6T. This relaxation is consistent with the localization of the charge creating a barrier for it moving from one lattice site to a neighboring one. Finally, the IPS was used to study the evolution of the surface band gap at the Mg/Ag(111) interface. The Mg(0001) surface band gap lies 1.6 eV below the Fermi level, and consequently shows no peak in the projected density of states for the IPS. A method for creating layer by layer growth of Mg on Ag(111) was determined using Auger Spectroscopy and low energy electron diffraction. By monitoring the decay of the intensity of the IPS versus coverage, it was determined that four layers of magnesium on Ag(111) is sufficient to completely eliminate the surface band gap

  1. Improving femtosecond laser pulse delivery through a hollow core photonic crystal fiber for temporally focused two-photon endomicroscopy

    E-Print Network [OSTI]

    Choi, Heejin

    In this paper, we present a strategy to improve delivery of femtosecond laser pulses from a regenerative amplifier through a hollow core photonic crystal fiber for temporally focused wide-field two-photon endomicroscopy. ...

  2. Thermomechanical Actuator-Based Three-Axis Optical Scanner for High-Speed Two-Photon Endomicroscope Imaging

    E-Print Network [OSTI]

    Chen, Shih-Chi

    This paper presents the design and characterization of a three-axis thermomechanical actuator-based endoscopic scanner for obtaining ex vivo two-photon images. The scanner consisted of two sub-systems: 1) an optical system ...

  3. Observation of two-photon absorption at low power levels using tapered optical fibers in rubidium vapor

    E-Print Network [OSTI]

    S. M. Hendrickson; M. M. Lai; T. B. Pittman; J. D. Franson

    2010-07-12T23:59:59.000Z

    Nonlinear optical effects can be enhanced in tapered optical fibers with diameters less than the wavelength of the propagating light. Here we report on the observation of two-photon absorption using tapered fibers in rubidium vapor at power levels of less than 150 nW. Transit-time broadening produces two-photon absorption spectra with sharp peaks that are very different from conventional line shapes.

  4. Two-Photon Interactions with Nuclear Breakup in Relativistic Heavy Ion Collisions

    SciTech Connect (OSTI)

    Baltz, Anthony J.; Gorbunov, Yuri; R Klein, Spencer; Nystrand, Joakim

    2010-07-07T23:59:59.000Z

    Highly charged relativistic heavy ions have high cross-sections for two-photon interactions. The photon flux is high enough that two-photon interactions may be accompanied by additional photonuclear interactions. Except for the shared impact parameter, these interactions are independent. Additional interactions like mutual Coulomb excitation are of experimental interest, since the neutrons from the nuclear dissociation provide a simple, relatively unbiased trigger. We calculate the cross sections, rapidity, mass and transverse momentum (p{sub T}) distributions for exclusive {gamma}{gamma} production of mesons and lepton pairs, and for {gamma}{gamma} reactions accompanied by mutual Coulomb dissociation. The cross-sections for {gamma}{gamma} interactions accompanied by multiple neutron emission (XnXn) and single neutron emission (1n1n) are about 1/10 and 1/100 of that for the unaccompanied {gamma}{gamma} interactions. We discuss the accuracy with which these cross-sections may be calculated. The typical p{sub T} of {gamma}{gamma} final states is several times smaller than for comparable coherent photonuclear interactions, so p{sub T} may be an effective tool for separating the two classes of interactions.

  5. Two-photon laser excitation of trapped 232Th+ ions via the 402 nm resonance line

    E-Print Network [OSTI]

    Herrera-Sancho, O A; Zimmermann, K; Tamm, Chr; Peik, E; Taichenachev, A V; Yudin, V I; Glowacki, P

    2012-01-01T23:59:59.000Z

    Experiments on one- and two-photon laser excitation of 232Th+ ions in a radiofrequency ion trap are reported. As the first excitation step, the strongest resonance line at 402 nm from the 6d^2 7s J=3/2 ground state to the 6d7s7p J=5/2 state at 24874 cm^{-1} is driven by radiation from an extended cavity diode laser. Spontaneous decay of the intermediate state populates a number of low-lying metastable states, thus limiting the excited state population and fluorescence signal obtainable with continuous laser excitation. We study the collisional quenching efficiency of helium, argon, and nitrogen buffer gases, and the effect of repumping laser excitation from the three lowest-lying metastable levels. The experimental results are compared with a four-level rate equation model, that allows us to deduce quenching rates for these buffer gases. Using laser radiation at 399 nm for the second step, we demonstrate two-photon excitation to the state at 49960 cm^{-1}, among the highest-lying classified levels of Th+. Thi...

  6. Two-photon double ionization of the helium atom by ultrashort pulses

    SciTech Connect (OSTI)

    Palacios, Alicia; Horner, Daniel A; Rescigno, Thomas N; McCurdy, C William

    2010-05-14T23:59:59.000Z

    Two-photon double ionization of the helium atom was the subject of early experiments at FLASH and will be the subject of future benchmark measurements of the associated electron angular and energy distributions. As the photon energy of a single femtosecond pulse is raised from the threshold for two-photon double ionization at 39.5 eV to beyond the sequential ionization threshold at 54.4 eV, the electron ejection dynamics change from the highly correlated motion associated with nonsequential absorption to the much less correlated sequential ionization process. The signatures of both processes have been predicted in accurate \\textit{ab initio} calculations of the joint angular and energy distributions of the electrons, and those predictions contain some surprises. The dominant terms that contribute to sequential ionization make their presence apparent several eV below that threshold. In two-color pump probe experiments with short pulses whose central frequencies require that the sequential ionization process necessarily dominates, a two-electron interference pattern emerges that depends on the pulse delay and the spin state of the atom.

  7. Two-photon-absorption spectrum of poly(di- n -hexylsilane) films

    SciTech Connect (OSTI)

    Soos, Z.G. (Department of Chemistry, Princeton University, Princeton, New Jersey 08544 (USA)); Kepler, R.G. (Sandia National Laboratories, Albuquerque, New Mexico 87185 (USA))

    1991-05-15T23:59:59.000Z

    Two-photon-absorption (TPA) spectra of poly(di-{ital n}-hexylsilane) (PDHS) films are obtained from 605 to 410 nm at 295 and 11 K, where the intensity is an order of magnitude higher. A strong TPA band is found above 5 eV and interpreted in terms of interacting {sigma} electrons in a Pariser-Parr-Pople (PPP) model. PPP models for (Si){sub {ital n}} chains relate the excitonic (one-photon) absorption at {ital E}{sub {ital g}}=3.4 in PDHS to the 4.2-eV TPA at the alternation gap and the high-energy TPA derived from two-electron excitations at {ital E}{sub {ital g}}. The smaller alternation gap in {pi}-conjugated polymers and their intense TPA above {ital E}{sub {ital g}} also indicate correlated states and differ qualitatively from single-particle descriptions.

  8. Evaluation of the two-photon absorption characteristics of GaSb/GaAs quantum rings

    SciTech Connect (OSTI)

    Wagener, M. C.; Botha, J. R. [Department of Physics, Nelson Mandela Metropolitan University, Port Elizabeth 6031 (South Africa); Carrington, P. J. [Department of Electronic and Electrical Engineering, University College London, London (United Kingdom); Krier, A. [Department of Physics, Lancaster University, Lancaster LA1 4YB (United Kingdom)

    2014-07-28T23:59:59.000Z

    The optical parameters describing the sub-bandgap response of GaSb/GaAs quantum rings solar cells have been obtained from photocurrent measurements using a modulated pseudo-monochromatic light source in combination with a second, continuous photo-filling source. By controlling the charge state of the quantum rings, the photoemission cross-sections describing the two-photon sub-bandgap transitions could be determined independently. Temperature dependent photo-response measurements also revealed that the barrier for thermal hole emission from the quantum rings is significantly below the quantum ring localisation energy. The temperature dependence of the sub-bandgap photo-response of the solar cell is also described in terms of the photo- and thermal-emission characteristics of the quantum rings.

  9. Measurement of the two-photon exchange contribution in elastic $ep$ scattering at VEPP-3

    E-Print Network [OSTI]

    A. V. Gramolin; J. Arrington; L. M. Barkov; V. F. Dmitriev; V. V. Gauzshtein; R. A. Golovin; R. J. Holt; V. V. Kaminsky; B. A. Lazarenko; S. I. Mishnev; N. Yu. Muchnoi; V. V. Neufeld; D. M. Nikolenko; I. A. Rachek; R. Sh. Sadykov; Yu. V. Shestakov; V. N. Stibunov; D. K. Toporkov; H. de Vries; S. A. Zevakov; V. N. Zhilich

    2011-12-22T23:59:59.000Z

    We report on the status of the Novosibirsk experiment on a precision measurement of the ratio $R$ of the elastic $e^+ p$ and $e^- p$ scattering cross sections. Such measurements determine the two-photon exchange effect in elastic electron-proton scattering. The experiment is conducted at the VEPP-3 storage ring using a hydrogen internal gas target. The ratio $R$ is measured with a beam energy of 1.6 GeV (electron/positron scattering angles are $\\theta = 55 \\div 75^{\\circ}$ and $\\theta = 15 \\div 25^{\\circ}$) and 1 GeV ($\\theta = 65 \\div 105^{\\circ}$). We briefly describe the experimental method, paying special attention to the radiative corrections. Some preliminary results are presented.

  10. Beyond the born approximation: Measuring the two-photon exchange effect at CLAS

    SciTech Connect (OSTI)

    Robert Paul Bennett

    2012-04-01T23:59:59.000Z

    Recent results from experiments at Jefferson Laboratory, Newport News VA, which measured the ratio of the electric to magnetic form factors of the proton, G{sub E}/G{sub M}, have forced us to reexamine the single photon exchange approximation in lepton-proton elastic scattering. Discrepancies between the ratio obtained via the time-tested Rosenbluth separation method and newer polarization transfer measurements, which differ by as much as a factor of three, may be resolved by considering the effect of two photon exchange (TPE) processes. The CLAS TPE experiment at Jefferson Laboratory, will determine the effect of two-photon exchange in elastic lepton-proton scattering by precisely measuring the ratio of positron-proton to electron-proton elastic cross sections over a large kinematic range (0.1 < {xi} < 0.96, 0.2 {ge} Q{sup 2} {le} 2.0 GeV{sup 2}). We accomplish this by directing the 5.5 GeV primary electron beam, provided by the Continuous Electron Beam Accelerator Facility (CEBAF), onto a set of radiators and converters to produce simultaneous and identical beams of electron and positrons which collide with our proton target. Acceptance and efficiency concerns are minimized by only considering the ratios of the elastic cross sections and by switching polarity of magnets in the beamline and the spectrometer. Guided by the results of a short 2006 test run and extensive GEANT based modeling, new shielding and beamline components were designed to maximize luminosity. We took data from November 2010 - February 2011. The unique experimental design and challenges of the TPE experiment and the current analysis status will be presented.

  11. Optical beam induced current measurements based on two-photon absorption process in 4H-SiC bipolar diodes

    SciTech Connect (OSTI)

    Hamad, H.; Raynaud, C.; Bevilacqua, P.; Tournier, D.; Planson, D. [Ampère Laboratory - UMR 5005, 21, Avenue Jean Capelle, 69621 Villeurbanne Cedex (France); Vergne, B. [Franco-Allemand Institute of Saint-Louis ISL, 5, Rue du Général Cassagnou, 68300 Saint-Louis (France)

    2014-02-24T23:59:59.000Z

    Using a pulsed green laser with a wavelength of 532?nm, a duration pulse of ?1?ns, and a mean power varying between 1 and 100?mW, induced photocurrents have been measured in 4H-SiC bipolar diodes. Considering the photon energy (2.33?eV) and the bandgap of 4H-SiC (3.2?eV), the generation of electron-hole pair by the conventional single photon absorption process should be negligible. The intensity of the measured photocurrents depends quadratically on the power beam intensity. This clearly shows that they are generated using two-photon absorption process. As in conventional OBIC (Optical Beam Induced Current), the measurements give an image of the electric field distribution in the structure under test, and the minority carrier lifetime can be extracted from the decrease of the photocurrent at the edge of the structure. The extracted minority carrier lifetime of 210?ns is consistent with results obtained in case of single photon absorption.

  12. Electromagnetically induced transparency in a five-level {Lambda} system dominated by two-photon resonant transitions

    SciTech Connect (OSTI)

    Yan Dong [College of Physics, Jilin University, Changchun 130012 (China); School of Science, Changchun University, Changchun 130022 (China); Gao Jinwei; Bao Qianqian; Yang Hong; Wang Heng; Wu Jinhui [College of Physics, Jilin University, Changchun 130012 (China)

    2011-03-15T23:59:59.000Z

    We study the steady optical response of a five-level atomic system in the parametric region where resonant two-photon transitions are much stronger than far-detuned single-photon transitions. We find that the concurrent absorption of two weak probe fields can be well suppressed in a narrow spectral region to attain electromagnetically induced transparency (EIT) via quantum destructive interference between different two-photon transition pathways. To gain a deeper insight into relevant physics, we adiabatically reduce this five-level system with trivial single-photon transitions into a three-level system with vanishing single-photon transitions by deriving an effective Hamiltonian. The two systems have almost the same two-photon absorption spectra exhibiting typical EIT features but are a little different in fine details. This means that most characteristics of two-photon quantum destructive interference are reserved after the adiabatic elimination approximation. In addition, we verify by numerical calculations that the two-photon EIT spectra are insensitive to the dipole-dipole interaction of cold Rydberg atoms when the uppermost level has a high principle quantum number.

  13. Enhanced two-photon excitation through optical fiber by single-mode propagation in a large core

    E-Print Network [OSTI]

    Tank, David

    Enhanced two-photon excitation through optical fiber by single-mode propagation in a large core Fritjof Helmchen, David W. Tank, and Winfried Denk Multiphoton excitation through optical fibers of applications efficient MPE through optical fibers is desirable. For example, single-mode fibers SMFs can

  14. Single-Shot Generation and Detection of a Two-Photon Generalized Binomial State in a Cavity

    E-Print Network [OSTI]

    R. Lo Franco; G. Compagno; A. Messina; A. Napoli

    2006-07-28T23:59:59.000Z

    A "quasi-deterministic" scheme to generate a two-photon generalized binomial state in a single-mode high-Q cavity is proposed. We also suggest a single-shot scheme to measure the generated state based on a probe two-level atom that "reads" the cavity field. The possibility of implementing the schemes is discussed.

  15. Theory of the Energy Levels and Precise Two--Photon Spectroscopy of Atomic Hydrogen and Deuterium 1

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Theory of the Energy Levels and Precise Two--Photon Spectroscopy of Atomic Hydrogen and Deuterium 1 of the energy levels of simple hydrogenic systems. We review recent two­photon spectroscopic measurements performed in Garching and the relevant theoretical predictions for the hydrogen energy levels. A good

  16. The Search for eta(1440) --> K^0_S K^pm ?^mp in Two-Photon Fusion at CLEO

    E-Print Network [OSTI]

    R. Ahohe; CLEO Collaboration

    2005-01-11T23:59:59.000Z

    We analyze 13.8 \\rm fb^{-1} of the integrated e^+e^- luminosity collected at 10.6 GeV center-of-mass energy with the CLEO II and CLEO II.V detectors to study exclusive two-photon production of hadrons with masses below 1.7{\\rm \\ GeV/c^2} decaying into the K^0_S K^\\pm \\pi^\\mp final state. We observe two statistically significant enhancements in the \\eta(1440) mass region. These enhancements have large transverse momentum which rules them out as being due to pseudoscalar resonances but is consistent with the production of axial-vector mesons. We use tagged two-photon events to study the properties of the observed enhancements and associate them with the production of f_1(1285) and f_1(1420). Our non-observation of \\eta(1440) is inconsistent by more than two standard deviations with the first observation of this resonance in two-photon collisions by the L3 experiment. We present our estimates for 90% confidence level upper limits on the products of two-photon partial widths of pseudoscalar hadrons and their branching fractions into K^0_S(\\pi^+\\pi^-)K^\\pm\\pi^\\mp.

  17. Excited electron dynamics in bulk ytterbium: Time-resolved two-photon photoemission and GW+T ab initio calculations

    E-Print Network [OSTI]

    Aeschlimann, Martin

    relaxation dynamics is played by the electronic structure of the system close to the Fermi level. For exampleExcited electron dynamics in bulk ytterbium: Time-resolved two-photon photoemission and GW+T ab November 2007 The excited electron dynamics in ytterbium is investigated by means of the time-resolved two

  18. Search for the standard model Higgs boson decaying into two photons in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    CMS Collaboration

    A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a center-of-mass energy of 7 TeV, which corresponds ...

  19. J Am Chem Soc . Author manuscript Long-lived two-photon excited luminescence of water-soluble europium

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    -soluble europium complex: applications in biological imaging using two-photon scanning microscopy Alexandre Picot 1 Maury Abstract A new europium complex presenting good solubility-photon scanning microscopy bio-imaging experiments on fixed cancer cells. MESH Keywords Europium ; chemistry

  20. Large Scale Laser Two-Photon Polymerization Structuring for Fabrication of Artificial Polymeric Scaffolds for Regenerative Medicine

    SciTech Connect (OSTI)

    Malinauskas, M.; Purlys, V.; Zukauskas, A.; Rutkauskas, M.; Danilevicius, P.; Paipulas, D.; Bickauskaite, G.; Gadonas, R.; Piskarskas, A. [Vilnius University, Physics Faculty, Department of Quantum Electronics, Laser Research Center, Sauletekio ave. 10, LT-10223 Vilnius (Lithuania); Bukelskis, L.; Baltriukiene, D.; Bukelskiene, V. [Institute of Biochemistry, Vivarium, Mokslininkuo str. 12, LT-08662 Vilnius (Lithuania); Sirmenis, R. [Vilnius University Hospital Santariskiuo Klinikos, Santariskiuo g. 2, LT-08661 Vilnius (Lithuania); Gaidukeviciute, A. [Institute of Electronic Structure and Laser, Foundation for Research and Technology Hellas, Vassilika Vouton, 711 10 Heraklion, Crete (Greece); Sirvydis, V. [Vilnius University, Faculty of Medicine, Heart Surgery Center, Santariskiuo 2, LT-08661, Vilnius (Lithuania)

    2010-11-10T23:59:59.000Z

    We present a femtosecond Laser Two-Photon Polymerization (LTPP) system of large scale three-dimensional structuring for applications in tissue engineering. The direct laser writing system enables fabrication of artificial polymeric scaffolds over a large area (up to cm in lateral size) with sub-micrometer resolution which could find practical applications in biomedicine and surgery. Yb:KGW femtosecond laser oscillator (Pharos, Light Conversion. Co. Ltd.) is used as an irradiation source (75 fs, 515 nm (frequency doubled), 80 MHz). The sample is mounted on wide range linear motor driven stages having 10 nm sample positioning resolution (XY--ALS130-100, Z--ALS130-50, Aerotech, Inc.). These stages guarantee an overall travelling range of 100 mm into X and Y directions and 50 mm in Z direction and support the linear scanning speed up to 300 mm/s. By moving the sample three-dimensionally the position of laser focus in the photopolymer is changed and one is able to write complex 3D (three-dimensional) structures. An illumination system and CMOS camera enables online process monitoring. Control of all equipment is automated via custom made computer software ''3D-Poli'' specially designed for LTPP applications. Structures can be imported from computer aided design STereoLihography (stl) files or programmed directly. It can be used for rapid LTPP structuring in various photopolymers (SZ2080, AKRE19, PEG-DA-258) which are known to be suitable for bio-applications. Microstructured scaffolds can be produced on different substrates like glass, plastic and metal. In this paper, we present microfabricated polymeric scaffolds over a large area and growing of adult rabbit myogenic stem cells on them. Obtained results show the polymeric scaffolds to be applicable for cell growth practice. It exhibit potential to use it for artificial pericardium in the experimental model in the future.

  1. Two photon absorption laser induced fluorescence measurements of neutral density in a helicon plasma

    SciTech Connect (OSTI)

    Galante, M. E.; Magee, R. M.; Scime, E. E. [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)] [Department of Physics, West Virginia University, Morgantown, West Virginia 26506 (United States)

    2014-05-15T23:59:59.000Z

    We have developed a new diagnostic based on two-photon absorption laser induced fluorescence (TALIF). We use a high intensity (5?MW/cm{sup 2}), narrow bandwidth (0.1?cm{sup ?1}) laser to probe the ground state of neutral hydrogen, deuterium and krypton with spatial resolution better than 0.2?cm, a time resolution of 10?ns, and a measurement cadence of 20?Hz. Here, we describe proof-of-principle measurements in a helicon plasma source that demonstrate the TALIF diagnostic is capable of measuring neutral densities spanning four orders of magnitude; comparable to the edge neutral gradients predicted in the DIII-D tokamak pedestal. The measurements are performed in hydrogen and deuterium plasmas and absolute calibration is accomplished through TALIF measurements in neutral krypton. The optical configuration employed is confocal, i.e., both light injection and collection are accomplished with a single lens through a single optical port in the vacuum vessel. The wavelength resolution of the diagnostic is sufficient to separate hydrogen and deuterium spectra and we present measurements from mixed hydrogen and deuterium plasmas that demonstrate isotopic abundance measurements are feasible. Time resolved measurements also allow us to explore the evolution of the neutral hydrogen density and temperature and effects of wall recycling. We find that the atomic neutral density grows rapidly at the initiation of the discharge, reaching the steady-state value within 1?ms. Additionally, we find that neutral hydrogen atoms are born with 0.08?eV temperatures, not 2?eV as is typically assumed.

  2. Excited state dynamics of liquid water: Insight from the dissociation reaction following two-photon excitation

    E-Print Network [OSTI]

    Elles, Christopher G.; Shkrob, Ilya A.; Crowell, Robert A.; Bradforth, Stephen E.

    2007-04-25T23:59:59.000Z

    V to ionization at 12.4eV. The two channels occur with similar yield for an excitation energy of 9.3eV. For the lowest excitation energy, the transient absorption at 267nm probes the geminate recombination kinetics of the H and OH fragments, providing a window...

  3. Two-Photon Study on the Electronic Interactions between the First Excited Singlet States in Carotenoid?Tetrapyrrole Dyads

    SciTech Connect (OSTI)

    Liao, Pen-Nan; Pillai, Smitha; Gust, Devens; Moore, Thomas A.; Moore, Ana L.; Walla, Peter J.

    2011-01-01T23:59:59.000Z

    Electronic interactions between the first excited states (S{sub 1}) of carotenoids (Car) of different conjugation lengths (8?11 double bonds) and phthalocyanines (Pc) in different Car?Pc dyad molecules were investigated by two-photon spectroscopy and compared with Car S{sub 1}?chlorophyll (Chl) interactions in photosynthetic light harvesting complexes (LHCs). The observation of Chl/Pc fluorescence after selective two-photon excitation of the Car S{sub 1} state allowed sensitive monitoring of the flow of energy between Car S{sub 1} and Pc or Chl. It is found that two-photon excitation excites to about 80% to 100% exclusively the carotenoid state Car S{sub 1} and that only a small fraction of direct tetrapyrrole two-photon excitation occurs. Amide-linked Car?Pc dyads in tetrahydrofuran demonstrate a molecular gear shift mechanism in that effective Car S{sub 1} ? Pc energy transfer is observed in a dyad with 9 double bonds in the carotenoid, whereas in similar dyads with 11 double bonds in the carotenoid, the Pc fluorescence is strongly quenched by Pc ? Car S{sub 1} energy transfer. In phenylamino-linked Car?Pc dyads in toluene extremely large electronic interactions between the Car S{sub 1} state and Pc were observed, particularly in the case of a dyad in which the carotenoid contained 10 double bonds. This observation together with previous findings in the same system provides strong evidence for excitonic Car S{sub 1}?Pc Q{sub y} interactions. Very similar results were observed with photosynthetic LHC II complexes in the past, supporting an important role of such interactions in photosynthetic down-regulation.

  4. Two-photon double ionization of H2 at 30 eV using Exterior Complex Scaling

    SciTech Connect (OSTI)

    Morales, Felipe; Martin, Fernando; Horner, Daniel; Rescigno, Thomas N.; McCurdy, C. William

    2009-01-20T23:59:59.000Z

    Calculations of fully differential cross sections for two-photon double ionization of the hydrogen molecule with photons of 30 eV are reported. The results have been obtained by using the method of exterior complex scaling, which allows one to construct essentially exact wave functions that describe thedouble continuum on a large, but finite, volume. The calculated cross sections are compared with those previously obtained by Colgan et al., and discrepancies are found for specific molecular orientations and electron ejection directions.

  5. Laser induced fluorescence and resonant two-photon ionization spectroscopy of jet-cooled 1-hydroxy-9,10-anthraquinone

    SciTech Connect (OSTI)

    Cho, Sung Haeng; Huh, Hyun; Kim, Hyung Min; Kim, Choong Ik; Kim, Nam Joon; Kim, Seong Keun [School of Chemistry, Seoul National University, Seoul 151-747 (Korea, Republic of)

    2005-01-15T23:59:59.000Z

    We carried out laser induced fluorescence and resonance enhanced two-color two-photon ionization spectroscopy of jet-cooled 1-hydroxy-9,10-anthraquinone (1-HAQ). The 0-0 band transition to the lowest electronically excited state was found to be at 461.98 nm (21 646 cm-1). A well-resolved vibronic structure was observed up to 1100 cm-1 above the 0-0 band, followed by a rather broad absorption band in the higher frequency region. Dispersed fluorescence spectra were also obtained. Single vibronic level emissions from the 0-0 band showed Stokes-shifted emission spectra. The peak at 2940 cm-1 to the red of the origin in the emission spectra was assigned as the OH stretching vibration in the ground state, whose combination bands with the C=O bending and stretching vibrations were also seen in the emission spectra. In contrast to the excitation spectrum, no significant vibronic activity was found for low frequency fundamental vibrations of the ground state in the emission spectrum. The spectral features of the fluorescence excitation and emission spectra indicate that a significant change takes place in the intramolecular hydrogen bonding structure upon transition to the excited state, such as often seen in the excited state proton (or hydrogen) transfer. We suggest that the electronically excited state of interest has a double minimum potential of the 9,10-quinone and the 1,10-quinone forms, the latter of which, the proton-transferred form of 1-HAQ, is lower in energy. On the other hand, ab initio calculations at the B3LYP/6-31G(d,p) level predicted that the electronic ground state has a single minimum potential distorted along the reaction coordinate of tautomerization. The 9,10-quinone form of 1-HAQ is the lowest energy structure in the ground state, with the 1,10-quinone form lying {approx}5000 cm-1 above it. The intramolecular hydrogen bond of the 9,10-quinone was found to be unusually strong, with an estimated bond energy of {approx}13 kcal/mol ({approx}4500 cm-1), probably due to the resonance-assisted nature of the hydrogen bonding involved.

  6. Two-photon double ionization of H2 at 30 eV using exterior complex scaling

    SciTech Connect (OSTI)

    Horner, Daniel A [Los Alamos National Laboratory; Morales, F [UNIV AUTONOMA DE MADRID; Martin, F [UNIV AUTONOMA DE MADRID; Rescigno, T N [LBNL; Mccurdy, C W [LBNL

    2009-01-01T23:59:59.000Z

    Calculations of fully differential cross sections for two-photon double ionization of the hydrogen molecule with photons of 30 eV are reported. The results have been obtained by using the method of exterior complex scaling, which allows one to construct essentially exact wave functions that describe the double continuum on a large, but finite, volume. The calculated cross sections are compared with those previously obtained by Colgan et al [1], and discrepancies are found for specific molecular orientations and electron ejection directions.

  7. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

    E-Print Network [OSTI]

    Johns, James

    2010-01-01T23:59:59.000Z

    creates islands of toluene with an exposed wetting layertoluene showed patchy growth, leaving elements of the wetting monolayer exposed.

  8. Angular and polarization analysis for two-photon decay of 2s hyperfine states of hydrogenlike Uranium

    E-Print Network [OSTI]

    Laleh Safari; Pedro Amaro; Jose Paulo Santos; Filippo Fratini

    2014-07-15T23:59:59.000Z

    The amplitude of two-photon transitions between hyperfine states in hydrogenlike ions is derived based on relativistic Dirac equation and second order perturbation theory. We study angular and linear polarization properties of the photon pair emitted in the decay of $2s$ states, where spin-flip and non-spin-flip transitions are highlighted. We pay particular attention to hydrogenlike uranium, since it is an ideal candidate for investigating relativistic and high-multipole effects, such as spin-flip transitions. Two types of emission patterns are identified: i) non-spin-flip transitions are found to be characterized by an angular distribution of the type $W(\\theta)\\sim1+\\cos^2\\theta$ while the polarizations of the emitted photons are parallel; ii) spin-flip transitions have somewhat smaller decay rates and are found to be characterized by an angular distribution of the type $W(\\theta)\\sim1-1/3\\cos^2\\theta$ while the polarizations of the emitted photons are orthogonal, where $\\theta$ is the angle between photons directions. Deviations due to non-dipole and relativistic contributions are evaluated for both types of transitions. This work is the first step toward exploring the effect of nucleus over the the angular and polarization properties of the photon pairs emitted by two-photon transitions.

  9. Giant Two-Photon Absorption Coefficient and Frequency Up-Converted Luminescence in Monolayer MoS2

    E-Print Network [OSTI]

    Li, Yuanxin; Zhang, Saifeng; Zhang, Xiaoyan; Feng, Yanyan; Wang, Kangpeng; Zhang, Long; Wang, Jun

    2015-01-01T23:59:59.000Z

    Strong two-photon absorption (TPA) in monolayer MoS2 is demonstrated in contrast to saturable absorption (SA) in multilayer MoS2 under the excitation of femtosecond laser pulses in the near infrared region. MoS2 in the forms of monolayer single crystal and multilayer triangular islands are grown on either quartz or SiO2/Si by employing the seeding method through chemistry vapor deposition. The nonlinear transmission measurements reveal that monolayer MoS2 possesses a giant nonsaturation TPA coefficient, larger than that of conventional semiconductors. As a result of TPA, two-photon pumped frequency up-converted luminescence is observed directly in the monolayer MoS2. For the multilayer MoS2, the SA response is demonstrated with the ratio of the excited-state absorption cross section to ground-state cross section of 0.18. In addition, the laser damage threshold of the monolayer MoS2 is 97 GW/cm2, larger than that of the multilayer MoS2 of 78 GW/cm2.

  10. Single and two-photon fluorescence control of Er{sup 3+} ions by phase-shaped femtosecond laser pulse

    SciTech Connect (OSTI)

    Zhang, Shian, E-mail: sazhang@phy.ecnu.edu.cn; Ding, Jingxin; Lu, Chenhui; Jia, Tianqing; Sun, Zhenrong, E-mail: zrsun@phy.ecnu.edu.cn [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China)] [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China); Xu, Shuwu [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China) [State Key Laboratory of Precision Spectroscopy, and Department of Physics, East China Normal University, Shanghai 200062 (China); School of Science, Nantong University, Nantong 226007 (China); Qiu, Jianrong [State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology, Wushan Road 381, Guangzhou 510640 (China)] [State Key Laboratory of Luminescent Materials and Devices, and Institute of Optical Communication Materials, South China University of Technology, Wushan Road 381, Guangzhou 510640 (China)

    2014-01-06T23:59:59.000Z

    We experimentally demonstrate the control of the single and two-photon fluorescence (SPF and TPF) in Er{sup 3+} ions by shaping the femtosecond laser pulse with a ? or square phase modulation. With the low laser intensity (8.4?×?10{sup 10}?W/cm{sup 2}), SPF keeps a constant while TPF is effectively suppressed by the two control schemes. With the high laser intensity (1.2?×?10{sup 13}?W/cm{sup 2}), both SPF and TPF are simultaneously enhanced or suppressed by the ? phase modulation, and SPF is enhanced while TPF is effectively suppressed by the square phase modulation. The up/down-conversion fluorescence enhancement, suppression, or tuning by the optical control method can greatly expand its applications in various related fields.

  11. Investigating two-photon double ionization of D2 by XUV-Pump -- XUV-Probe experiments at FLASH

    SciTech Connect (OSTI)

    FLASH Collaboration; Jiang, Y.; Rudenko, A.; Perez-Torres, J.; Foucar, L.; Kurka, M.; Kuhnel, K.; Toppin, M.; Plesiat, E.; Morales, F.; Martin, F.; Herrwerth, O.; Lezius, M.; Kling, M.; Jahnke, T.; Dorner, R.; Sanz-Vicario, J.; van Tilborg, J.; Belkacem, A.; Schulz, M.; Ueda, K.; Zouros, T.; Dusterer, S.; Treusch, R.; Schroter, C.; Moshammer, R.; Ullrich, J.

    2010-08-02T23:59:59.000Z

    Using a novel split-mirror set-up attached to a Reaction Microscope at the Free electron LASer in Hamburg (FLASH) we demonstrate an XUV-pump -- XUV-probe ((hbar omega = 38 eV) experiment by tracing the ultra-fast nuclear wave-packet motion in the D2+ (1s sigma g-state) with<10 fs time resolution. Comparison with time-dependent calculations yields excellent agreement with the measured vibrational period of 22+-4 fs in D2+, points to the importance of the inter-nuclear distance dependent ionization probability and paves the way to control sequential and non-sequential two-photon double ionization contributions.

  12. Two photon absorption and its saturation of WS2 and MoS2 monolayer and few-layer films

    E-Print Network [OSTI]

    Zhang, Saifeng; McEvoy, Niall; O'Brien, Maria; Winters, Sinéad; Berner, Nina C; Yim, Chanyoung; Zhang, Xiaoyan; Chen, Zhanghai; Zhang, Long; Duesberg, Georg S; Wang, Jun

    2015-01-01T23:59:59.000Z

    The optical nonlinearity of WS2, MoS2 monolayer and few-layer films was investigated using the Z-scan technique with femtosecond pulses from the visible to the near infrared. The dependence of nonlinear absorption of the WS2 and MoS2 films on layer number and excitation wavelength was studied systematically. WS2 with 1~3 layers exhibits a giant two-photon absorption (TPA) coefficient. Saturation of TPA for WS2 with 1~3 layers and MoS2 with 25~27 layers was observed. The giant nonlinearity of WS2 and MoS2 is attributed to two dimensional confinement, a giant exciton effect and the band edge resonance of TPA.

  13. Studies of photoionization in liquids using a laser two-photon ionization conductivity technique. [Potoionization of pyrene, fluoranthene and TMPD in liquid n-pentane

    SciTech Connect (OSTI)

    Siomos, K.; Christophorou, L.G.

    1981-01-01T23:59:59.000Z

    One-photon ionization studies of solute molecules in a liquid medium are limited by the absorption of the host medium. A laser two-photon ionization (TPI) technique using a frequency tunable dye laser has been developed, whereby the photoionization threshold of a solute molecule was determined from the induced conductivity in the liquid medium under study due to electron-ion pair formation via two-photon ionization of the solute. The two-photon induced electron-ion current is measured as a function of the laser wavelength, lambda/sub laser/. In this paper, results are reported and discussed on the photoionization of N,N,N',N'-tetramethyl-p-phenylenediamine (TMPD), pyrene and fluoranthene in liquid n-pentane (n-Pt).

  14. First study of ?c(1S), ?(1760) and X(1835) production via ?'???? final states in two-photon collisions

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

    Zhang, C. C.; Aihara, H.; Asner, D. M.; Aushev, T.; Bakich, A. M.; Ban, Y.; Belous, K.; Bischofberger, M.; Browder, T. E.; Chen, A.; et al

    2012-09-01T23:59:59.000Z

    The invariant mass spectrum of the ?'???? final state produced in two-photon collisions is obtained using a 673 fb?¹ data sample collected in the vicinity of the ?(4S) resonance with the Belle detector at the KEKB asymmetric-energy e?e? collider. We observe a clear signal of the ?c(1S) and measure its mass and width to be M(?c(1S))=(2982.7±1.8(stat)±2.2(syst)±0.3(model)) MeV/c² and ?(?c(1S))=(37.8+5.8–5.3(stat)±2.8(syst)±1.4(model)) MeV/c². The third error is an uncertainty due to possible interference between the ?c(1S) and a nonresonant component. We also report the first evidence for ?(1760) decay to?'????; we find two solutions for its parameters, depending on the inclusion or notmore »of the X(1835), whose existence is of marginal significance in our data. From a fit to the mass spectrum using coherent X(1835) and ?(1760) resonant amplitudes, we set a 90% confidence level upper limit on the product ???B(?'????) for the X(1835).« less

  15. First study of ?c(1S), ?(1760) and X(1835) production via ?'???? final states in two-photon collisions

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

    Zhang, C. C.; Aihara, H.; Asner, D. M.; Aushev, T.; Bakich, A. M.; Ban, Y.; Belous, K.; Bischofberger, M.; Browder, T. E.; Chen, A.; Cheon, B. G.; Chilikin, K.; Chistov, R.; Choi, Y.; Dalseno, J.; Danilov, M.; Eidelman, S.; Feindt, M.; Gaur, V.; Gabyshev, N.; Goh, Y. M.; Han, Y. L.; Hayashii, H.; Horii, Y.; Hou, W.-S.; Hyun, H. J.; Iijima, T.; Inami, K.; Ishikawa, A.; Iwabuchi, M.; Julius, T.; Kiesling, C.; Kim, H. O.; Kim, M. J.; Kim, Y. J.; Ko, B. R.; Kodyš, P.; Korpar, S.; Krokovny, P.; Kuzmin, A.; Li, J.; Libby, J.; Liu, Y.; Liu, Z. Q.; Louvot, R.; Matvienko, D.; McOnie, S.; Mizuk, R.; Nakano, E.; Nakao, M.; Nakazawa, H.; Natkaniec, Z.; Nishida, S.; Ohshima, T.; Okuno, S.; Olsen, S. L.; Pakhlov, P.; Pakhlova, G.; Park, H.; Park, H. K.; Pestotnik, R.; Petri?, M.; Piilonen, L. E.; Röhrken, M.; Ryu, S.; Sahoo, H.; Sakai, Y.; Santel, D.; Sanuki, T.; Schneider, O.; Schwanda, C.; Sevior, M. E.; Shapkin, M.; Shebalin, V.; Shen, C. P.; Shibata, T.-A.; Shiu, J.-G.; Shwartz, B.; Smerkol, P.; Sohn, Y.-S.; Solovieva, E.; Stani?, S.; Stari?, M.; Sumihama, M.; Sumiyoshi, T.; Tikhomirov, I.; Uchida, M.; Uehara, S.; Uglov, T.; Unno, Y.; Uno, S.; Varner, G.; Vinokurova, A.; Vorobyev, V.; Wang, P.; Wang, X. L.; Watanabe, Y.; Williams, K. M.; Yabsley, B. D.; Yamashita, Y.; Yuan, C. Z.; Zhang, Z. P.; Zhulanov, V.

    2012-09-01T23:59:59.000Z

    The invariant mass spectrum of the ?'???? final state produced in two-photon collisions is obtained using a 673 fb?¹ data sample collected in the vicinity of the ?(4S) resonance with the Belle detector at the KEKB asymmetric-energy e?e? collider. We observe a clear signal of the ?c(1S) and measure its mass and width to be M(?c(1S))=(2982.7±1.8(stat)±2.2(syst)±0.3(model)) MeV/c² and ?(?c(1S))=(37.8+5.8–5.3(stat)±2.8(syst)±1.4(model)) MeV/c². The third error is an uncertainty due to possible interference between the ?c(1S) and a nonresonant component. We also report the first evidence for ?(1760) decay to?'????; we find two solutions for its parameters, depending on the inclusion or not of the X(1835), whose existence is of marginal significance in our data. From a fit to the mass spectrum using coherent X(1835) and ?(1760) resonant amplitudes, we set a 90% confidence level upper limit on the product ???B(?'????) for the X(1835).

  16. NEAR-IR TWO PHOTON MICROSCOPY IMAGING OF SILICA NANOPARTICLES FUNCTIONALIZED WITH ISOLATED SENSITIZED Yb(III) CENTERS

    SciTech Connect (OSTI)

    Lapadula, Giuseppe; Bourdolle, Adrien; Allouche, Florian; Conley, Matthew P.; Maron, Laurent; Lukens, Wayne W.; Guyot, Yannick; Andraud, Chantal; Brasselet, Sophie; Copé; ret, Christophe; Maury, Olivier; Andersen, Richard A.

    2013-01-12T23:59:59.000Z

    Bright nano objects emitting in the near infrared with a maximal cross section of 41.4 x 103 GM (Goppert Mayer), were prepared by implanting ca. 180 4,4 diethylaminostyryl 2,2 bipyridine (DEAS) Yb(III) complexes on the surface of 12 nm silica nanoparticles. The surface complexes ([DEAS Ln SiO2], Ln =Y,Yb) were characterized using IR, solid state NMR, UV Vis, EXAFS spectroscopies in combination with the preparation and characterization of similar molecular analogues by analytical techniques (IR, solution NMR, UV Vis, X ray crystallography) as well as DFT calculations. Starting from the partial dehydroxylation of the silica at 700 C on high vacuum having 0.8 OH.nm 2, the grafting of Ln(N(SiMe3)2)3 generate ?SiO Ln(N(SiMe3)2)2, which upon thermal step and coordination of the DEAS chromophore yields (?SiO)3Ln(DEAS). Surface and molecular analogues display similar properties, in terms of DEAS binding constants absorption maxima and luminescence properties (intense emission band assigned to a ligand centered CT fluorescence and life time) in the solid state, consistent with the molecular nature of the surface species. The densely functionalized nanoparticles can be dispersed via ultra-sonication in small ca. 15-20 nm aggregates (1 to 6 elementary particles) that were detected using two photon microscopy imaging at 720 nm excitation, making them promising nano objects for bio imaging.

  17. Search for a Higgs-like boson decaying to two photons in proton antiproton collisions at center of mass energy of 1.96 TeV

    E-Print Network [OSTI]

    Chen, Guo

    2013-05-31T23:59:59.000Z

    We present a search for the Standard Model (SM) Higgs boson decaying to two photons using the 9.6 fb-1 of proton antiproton collisions at center of mass energy of 1.96 TeV collected by the D0 detector at the Tevatron from ...

  18. Resonant two-photon ionization spectroscopy of jet-cooled PdC Jon D. Langenberg, Lian Shao, and Michael D. Morsea)

    E-Print Network [OSTI]

    Morse, Michael D.

    Resonant two-photon ionization spectroscopy of jet-cooled PdC Jon D. Langenberg, Lian Shao April 1999; accepted 21 May 1999 The first optical investigation of the spectra of diatomic PdC has of PdC, which is studied to add to the growing body of knowledge surrounding the tran- sition metal

  19. A Super-Additivity Inequality for Channel Capacity of Classical-Quantum Channels

    E-Print Network [OSTI]

    Rahul Jain

    2009-02-20T23:59:59.000Z

    We show a super-additivity inequality for the channel capacity of classical-quantum (c - q) channels.

  20. Demonstration of a novel technique to measure two-photon exchange effects in elastic $e^\\pm p$ scattering

    E-Print Network [OSTI]

    M. Moteabbed; M. Niroula; B. A. Raue; L. B. Weinstein; D. Adikaram; J. Arrington; W. K. Brooks; J. Lachniet; Dipak Rimal; M. Ungaro; K. P. Adhikari; M. Aghasyan; M. J. Amaryan; S. Anefalos Pereira; H. Avakian; J. Ball; N. A. Baltzell; M. Battaglieri; V. Batourine; I. Bedlinskiy; R. P. Bennett; A. S. Biselli; J. Bono; S. Boiarinov; W. J. Briscoe; V. D. Burkert; D. S. Carman; A. Celentano; S. Chandavar; P. L. Cole; P. Collins; M. Contalbrigo; O. Cortes; V. Crede; A. D'Angelo; N. Dashyan; R. De Vita; E. De Sanctis; A. Deur; C. Djalali; D. Doughty; R. Dupre; H. Egiyan; L. El Fassi; P. Eugenio; G. Fedotov; S. Fegan; R. Fersch; J. A. Fleming; N. Gevorgyan; G. P. Gilfoyle; K. L. Giovanetti; F. X. Girod; J. T. Goetz; W. Gohn; E. Golovatch; R. W. Gothe; K. A. Griffioen; M. Guidal; N. Guler; L. Guo; K. Hafidi; H. Hakobyan; C. Hanretty; N. Harrison; D. Heddle; K. Hicks; D. Ho; M. Holtrop; C. E. Hyde; Y. Ilieva; D. G. Ireland; B. S. Ishkhanov; E. L. Isupov; H. S. Jo; K. Joo; D. Keller; M. Khandaker; A. Kim; F. J. Klein; S. Koirala; A. Kubarovsky; V. Kubarovsky; S. E. Kuhn; S. V. Kuleshov; S. Lewis; H. Y. Lu; M. MacCormick; I . J . D. MacGregor; D. Martinez; M. Mayer; B. McKinnon; T. Mineeva; M. Mirazita; V. Mokeev; R. A. Montgomery; K. Moriya; H. Moutarde; E. Munevar; C. Munoz Camacho; P. Nadel-Turonski; R. Nasseripour; S. Niccolai; G. Niculescu; I. Niculescu; M. Osipenko; A. I. Ostrovidov; L. L. Pappalardo; R. Paremuzyan; K. Park; S. Park; E. Phelps; J. J. Phillips; S. Pisano; O. Pogorelko; S. Pozdniakov; J. W. Price; S. Procureur; D. Protopopescu; A. J. R. Puckett; M. Ripani; G. Rosner; P. Rossi; F. Sabatié; M. S. Saini; C. Salgado; D. Schott; R. A. Schumacher; E. Seder; H. Seraydaryan; Y. G. Sharabian; E. S. Smith; G. D. Smith; D. I. Sober; D. Sokhan; S. Stepanyan; S. Strauch; W. Tang; C. E. Taylor; Ye Tian; S. Tkachenko; H. Voskanyan; E. Voutier; N. K. Walford; M. H. Wood; N. Zachariou; L. Zana; J. Zhang; Z. W. Zhao; I. Zonta

    2013-07-10T23:59:59.000Z

    The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. We present the results of a new experimental technique for making direct $e^\\pm p$ comparisons, which has the potential to make precise measurements over a broad range in $Q^2$ and scattering angles. We use the Jefferson Lab electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of $Q^2$ and scattering angle. Nonetheless, this measurement yields a data sample for $e^\\pm p$ with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. The final ratio of positron to electron scattering: $R=1.027\\pm0.005\\pm0.05$ for $=0.206$ GeV$^2$ and $0.830\\leq \\epsilon\\leq 0.943$.

  1. Demonstration of a novel technique to measure two-photon exchange effects in elastic e±p scattering

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

    Moteabbed, Maryam [Florida Institute of Technology; Niroula, Megh [Old Dominion University; Raue, Brian [Florida International University; Weinstein, Lawrence [Old Dominion University

    2013-08-01T23:59:59.000Z

    The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. The TPE contributions depend on the sign of the lepton charge in e±p scattering, but the luminosities of secondary positron beams limited past measurement at large scattering angles, where the TPE effects are believe to be most significant. We present the results of a new experimental technique for making direct e±p comparisons, which has the potential to make precise measurements over a broad range in Q2 and scattering angles. We use the Jefferson Laboratory electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of Q2 and scattering angle. Nonetheless, this measurement yields a data sample for e±p with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. Because we ran with only one polarity for the chicane, we are unable to study the difference between the incoming electron and positron beams. This systematic effect leads to the largest uncertainty in the final ratio of positron to electron scattering: R=1.027±0.005±0.05 for 2 >=0.206 GeV2 and 0.830 ? ? ? 0.943. We have demonstrated that the tertiary e± beam generated using this technique provides the opportunity for dramatically improved comparisons of e±p scattering, covering a significant range in both Q2 and scattering angle. Combining data with different chicane polarities will allow for detailed studies of the difference between the incoming e+ and e- beams.

  2. Demonstration of a novel technique to measure two-photon exchange effects in elastic e±p scattering

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

    Moteabbed, Maryam; Niroula, Megh; Raue, Brian; Weinstein, Lawrence

    2013-08-01T23:59:59.000Z

    The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. The TPE contributions depend on the sign of the lepton charge in e±p scattering, but the luminosities of secondary positron beams limited past measurement at large scattering angles, where the TPE effects are believe to be most significant. We present the results of a new experimental technique for making direct e±p comparisons, which has themore »potential to make precise measurements over a broad range in Q2 and scattering angles. We use the Jefferson Laboratory electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of Q2 and scattering angle. Nonetheless, this measurement yields a data sample for e±p with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. Because we ran with only one polarity for the chicane, we are unable to study the difference between the incoming electron and positron beams. This systematic effect leads to the largest uncertainty in the final ratio of positron to electron scattering: R=1.027±0.005±0.05 for 2 >=0.206 GeV2 and 0.830 ? ? ? 0.943. We have demonstrated that the tertiary e± beam generated using this technique provides the opportunity for dramatically improved comparisons of e±p scattering, covering a significant range in both Q2 and scattering angle. Combining data with different chicane polarities will allow for detailed studies of the difference between the incoming e+ and e- beams.« less

  3. Recoil-Ion Momentum Distributions for Two-Photon Double Ionization of He and Ne by 44 eV Free-Electron Laser Radiation

    SciTech Connect (OSTI)

    Rudenko, A.; Moshammer, R.; Ullrich, J. [Max-Planck Advanced Study Group at CFEL, Notkestrasse 85, 22607 Hamburg (Germany); Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Foucar, L.; Havermeier, T.; Smolarski, M.; Schoessler, S.; Cole, K.; Schoeffler, M.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, 60486 Frankfurt (Germany); Kurka, M.; Ergler, Th.; Kuehnel, K. U.; Jiang, Y. H.; Voitkiv, A.; Najjari, B.; Luedemann, S.; Schroeter, C. D. [Max-Planck-Institut fuer Kernphysik, Saupfercheckweg 1, 69117 Heidelberg (Germany); Kheifets, A. [Research School of Physical Sciences, Australian University, Canberra, ACT 0200 (Australia); Duesterer, S. [DESY, Notkestrasse 85, 22607 Hamburg (Germany)] (and others)

    2008-08-15T23:59:59.000Z

    Recoil-ion momentum distributions for two-photon double ionization of He and Ne (({Dirac_h}/2{pi}){omega}=44 eV) have been recorded with a reaction microscope at FLASH (the free-electron laser at Hamburg) at an intensity of {approx}1x10{sup 14} W/cm{sup 2} exploring the dynamics of the two fundamental two-photon-two-electron reaction pathways, namely, sequential and direct (or nonsequential) absorption of the photons. We find strong differences in the recoil-ion momentum patterns for the two mechanisms pointing to the significantly different two-electron emission dynamics and thus provide serious constraints for theoretical models.

  4. Search for the standard model Higgs boson decaying into two photons in pp collisions at sqrt(s)=7 TeV

    SciTech Connect (OSTI)

    Chatrchyan, S. [Yerevan Physical Institute (Armenia); et al.,

    2012-04-01T23:59:59.000Z

    A search for a Higgs boson decaying into two photons is described. The analysis is performed using a dataset recorded by the CMS experiment at the LHC from pp collisions at a centre-of-mass energy of 7 TeV, which corresponds to an integrated luminosity of 4.8 inverse femtobarns. Limits are set on the cross section of the standard model Higgs boson decaying to two photons. The expected exclusion limit at 95% confidence level is between 1.4 and 2.4 times the standard model cross section in the mass range between 110 and 150 GeV. The analysis of the data excludes, at 95% confidence level, the standard model Higgs boson decaying into two photons in the mass range 128 to 132 GeV. The largest excess of events above the expected standard model background is observed for a Higgs boson mass hypothesis of 124 GeV with a local significance of 3.1 sigma. The global significance of observing an excess with a local significance greater than 3.1 sigma anywhere in the search range 110-150 GeV is estimated to be 1.8 sigma. More data are required to ascertain the origin of this excess.

  5. Demonstration of a novel technique to measure two-photon exchange effects in elastic e±p scattering

    SciTech Connect (OSTI)

    Moteabbed, Maryam [Florida Institute of Technology; Niroula, Megh [Old Dominion University; Raue, Brian [Florida International University; Weinstein, Lawrence [Old Dominion University

    2013-08-01T23:59:59.000Z

    The discrepancy between proton electromagnetic form factors extracted using unpolarized and polarized scattering data is believed to be a consequence of two-photon exchange (TPE) effects. However, the calculations of TPE corrections have significant model dependence, and there is limited direct experimental evidence for such corrections. The TPE contributions depend on the sign of the lepton charge in e±p scattering, but the luminosities of secondary positron beams limited past measurement at large scattering angles, where the TPE effects are believe to be most significant. We present the results of a new experimental technique for making direct e±p comparisons, which has the potential to make precise measurements over a broad range in Q2 and scattering angles. We use the Jefferson Laboratory electron beam and the Hall B photon tagger to generate a clean but untagged photon beam. The photon beam impinges on a converter foil to generate a mixed beam of electrons, positrons, and photons. A chicane is used to separate and recombine the electron and positron beams while the photon beam is stopped by a photon blocker. This provides a combined electron and positron beam, with energies from 0.5 to 3.2 GeV, which impinges on a liquid hydrogen target. The large acceptance CLAS detector is used to identify and reconstruct elastic scattering events, determining both the initial lepton energy and the sign of the scattered lepton. The data were collected in two days with a primary electron beam energy of only 3.3 GeV, limiting the data from this run to smaller values of Q2 and scattering angle. Nonetheless, this measurement yields a data sample for e±p with statistics comparable to those of the best previous measurements. We have shown that we can cleanly identify elastic scattering events and correct for the difference in acceptance for electron and positron scattering. Because we ran with only one polarity for the chicane, we are unable to study the difference between the incoming electron and positron beams. This systematic effect leads to the largest uncertainty in the final ratio of positron to electron scattering: R=1.027±0.005±0.05 for < Q2 >=0.206 GeV2 and 0.830 ? ? ? 0.943. We have demonstrated that the tertiary e± beam generated using this technique provides the opportunity for dramatically improved comparisons of e±p scattering, covering a significant range in both Q2 and scattering angle. Combining data with different chicane polarities will allow for detailed studies of the difference between the incoming e+ and e- beams.

  6. Tracing direct and sequential two-photon double ionization of D{sub 2} in femtosecond extreme-ultraviolet laser pulses

    SciTech Connect (OSTI)

    Jiang, Y. H.; Kurka, M.; Kuehnel, K. U.; Ergler, Th.; Schroeter, C. D.; Moshammer, R. [Max-Planck-Institut fuer Kernphysik, D-69117 Heidelberg (Germany); Rudenko, A.; Foucar, L. [Max-Planck Advanced Study Group at CFEL, D-22607 Hamburg (Germany); Plesiat, E.; Perez-Torres, J. F.; Martin, F. [Departamento de Quimica C-9, Universidad Autonoma de Madrid, E-28049 Madrid (Spain); Herrwerth, O.; Lezius, M.; Kling, M. F. [Max-Planck-Institut fuer Quantenoptik, D-85748 Garching (Germany); Titze, J.; Jahnke, T.; Doerner, R. [Institut fuer Kernphysik, Universitaet Frankfurt, D-60486 Frankfurt (Germany); Sanz-Vicario, J. L. [Instituto de Fisica, Universidad de Antioquia, Medellin (Colombia); Schoeffler, M.; Tilborg, J. van [Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2010-02-15T23:59:59.000Z

    Two-photon double ionization (TPDI) of D{sub 2} is studied for 38-eV photons at the Free Electron Laser in Hamburg (FLASH). Based on model calculations, instantaneous and sequential absorption pathways are identified as separated peaks in the measured D{sup +}+D{sup +} fragment kinetic energy release (KER) spectra. The instantaneous process appears at high KER, corresponding to ionization at the molecule's equilibrium distance, in contrast to sequential ionization mainly leading to low-KER contributions. Measured fragment angular distributions are in good agreement with theory.

  7. Implications of Channelization and

    E-Print Network [OSTI]

    Gray, Matthew

    · Dams · Highways · Irrigation · Levees · Oilfield Canals · Channelization Reasons for Channelization

  8. Kinetics of generation, relaxation, and accumulation of electronic excitations under two-photon interband picosecond absorption in tungstate and molibdate crystals

    SciTech Connect (OSTI)

    Lukanin, V. I.; Karasik, A. Ya., E-mail: karasik@lst.gpi.ru [Russian Academy of Sciences, Prokhorov General Physics Institute (Russian Federation)

    2013-08-15T23:59:59.000Z

    Under two-photon 523.5 nm interband picosecond laser excitation, we measured the kinetics of induced absorption in PbWO{sub 4}, ZnWO{sub 4}, and PbMoO{sub 4} crystals with 532 to 633 nm continuous probe radiation. We obtained real-time information about the dynamics of the generation, relaxation, and accumulations of electronic excitations over a wide time range (from picoseconds to hundreds of seconds) and the 77-300 K temperature range. For the studied crystals, exponential temperature-independent growth of the induced absorption (IA) with 60 ns rise time reflects the dynamics of the generation of electronic excitation. The kinetics of the IA exponential growth with temperature-dependent 3.5-11 {mu}s time constants reflect the dynamics of energy migration between neighboring tungstate (molibdate) ions to traps for the studied crystals. The multiexponential relaxation absorption kinetics strongly depend on temperature, and the relaxation decay time of induced absorption increased from tens to hundreds of milliseconds to seconds under crystal cooling from 300 to 77 K. We found that the increase in the laser pump repetition rate (0-10 Hz) leads to the accumulation of electronic excitations. Control of the repetition rate and the number of excitations allowed us to change the relaxation time of the induced absorption by more than two orders of magnitude. Due to accumulation of excitations at 77 K, the absorption relaxation time can exceed 100 s for PbWO{sub 4} and PbMoO{sub 4} crystals. In the initially transparent crystals, two-photon interband absorption (2PA) leads to crystals opacity at the 523 and 633 nm wavelengths. (An inverse optical transmission of the crystals exceeds 50-55 at a 50-100 GW/cm{sup 2} pump intensity.) Measured at {approx}1 mW probe radiation of 532 and 633 nm wavelengths, the induced absorption values are comparable with those obtained under two-photon absorption at {approx}5 kW pump power. An optical 2PA shutter for the visible spectral range is proposed with a variable shutting time from hundreds of microseconds to tens of seconds.

  9. Absolute frequency measurement of an SF6 two-photon line using a femtosecond optical comb and sum-frequency generation

    E-Print Network [OSTI]

    Anne Amy-Klein; Andrei Goncharov; Mickael Guinet; Christophe Daussy; Olivier Lopez; Alexander Shelkovnikov; Christian Chardonnet

    2005-09-07T23:59:59.000Z

    We demonstrate a new simple technique to measure IR frequencies near 30 THz using a femtosecond (fs) laser optical comb and sum-frequency generation. The optical frequency is directly compared to the distance between two modes of the fs laser, and the resulting beat note is used to control this distance which depends only on the repetition rate fr of the fs laser. The absolute frequency of a CO2 laser stabilized onto an SF6 two-photon line has been measured for the first time. This line is an attractive alternative to the usual saturated absorption OsO4 resonances used for the stabilization of CO2 lasers. First results demonstrate a fractional Allan deviation of 3.10-14 at 1 s.

  10. Absolute frequency measurement of an SF6 two-photon line using a femtosecond optical comb and sum-frequency generation

    E-Print Network [OSTI]

    Amy-Klein, A; Guinet, M; Daussy, C; López, O; Shelkovnikov, A; Chardonnet, C; Amy-Klein, Anne; Goncharov, Andrei; Guinet, Mickael; Daussy, Christophe; Lopez, Olivier; Shelkovnikov, Alexander; Chardonnet, Christian

    2005-01-01T23:59:59.000Z

    We demonstrate a new simple technique to measure IR frequencies near 30 THz using a femtosecond (fs) laser optical comb and sum-frequency generation. The optical frequency is directly compared to the distance between two modes of the fs laser, and the resulting beat note is used to control this distance which depends only on the repetition rate fr of the fs laser. The absolute frequency of a CO2 laser stabilized onto an SF6 two-photon line has been measured for the first time. This line is an attractive alternative to the usual saturated absorption OsO4 resonances used for the stabilization of CO2 lasers. First results demonstrate a fractional Allan deviation of 3.10-14 at 1 s.

  11. Enhanced photoluminescence due to two-photon enhanced three-photon absorption in Mn{sup 2+}-doped ZnS quantum dots

    SciTech Connect (OSTI)

    Subha, Radhu [Department of Physics, Indian Institute of Technology, Madras, Chennai, 600036, India and Department of Physics, National University of Singapore (NUS), 2 Science Drive 3, Singapore, 117542 (Singapore); Nalla, Venkatram; Ji, Wei, E-mail: phyjiwei@nus.edu.sg [Department of Physics, National University of Singapore (NUS), 2 Science Drive 3, Singapore, 117542 (Singapore); Feng, Xiaobo [School of Physics and Electronic Information Technology, Yunnan Normal University (China); Vijayan, C. [Department of Physics, Indian Institute of Technology, Madras, Chennai, 600036 (India)

    2014-10-15T23:59:59.000Z

    In this work, we have investigated the multi-photon absorption induced photoluminescence in Mn{sup 2+}-doped ZnS quantum dots in the wavelength range 860 – 1050 nm (Near-Infrared Window I). The observed three-photon action cross-section has been compared with the theoretical prediction under four band approximation. An enhancement of four to five orders has been observed in the range from 970 to 1050 nm compared to the theoretical value, which is attributed to two-photon enhanced three-photon absorption. Transient lifetime measurements reveal a lifetime of 0.35 ± 0.3 ms, which is four to five orders higher than other conventional fluorescent probes.

  12. Geometric pumping in autophoretic channels

    E-Print Network [OSTI]

    Sebastien Michelin; Thomas D. Montenegro Johnson; Gabriele De Canio; Nicolas Lobato-Dauzier; Eric Lauga

    2015-05-07T23:59:59.000Z

    Many microfluidic devices use macroscopic pressure differentials to overcome viscous friction and generate flows in microchannels. In this work, we investigate how the chemical and geometric properties of the channel walls can drive a net flow by exploiting the autophoretic slip flows induced along active walls by local concentration gradients of a solute species. We show that chemical patterning of the wall is not required to generate and control a net flux within the channel, rather channel geometry alone is sufficient. Using numerical simulations, we determine how geometric characteristics of the wall influence channel flow rate, and confirm our results analytically in the asymptotic limit of lubrication theory.

  13. Geometric pumping in autophoretic channels

    E-Print Network [OSTI]

    Michelin, Sebastien; De Canio, Gabriele; Lobato-Dauzier, Nicolas; Lauga, Eric

    2015-01-01T23:59:59.000Z

    Many microfluidic devices use macroscopic pressure differentials to overcome viscous friction and generate flows in microchannels. In this work, we investigate how the chemical and geometric properties of the channel walls can drive a net flow by exploiting the autophoretic slip flows induced along active walls by local concentration gradients of a solute species. We show that chemical patterning of the wall is not required to generate and control a net flux within the channel, rather channel geometry alone is sufficient. Using numerical simulations, we determine how geometric characteristics of the wall influence channel flow rate, and confirm our results analytically in the asymptotic limit of lubrication theory.

  14. Discovery Channel

    E-Print Network [OSTI]

    Lovley, Derek

    and sonar to spot passing ships and submarines. And, for people living in poor, remote communitiesDiscovery Channel :: Bacteria Power: Future Energy? Page 1 September 10, 2003 EDT Bacteria Power: Energy Of The Future? AFP R. ferriducens: "Bacterial Battery" Sept. 9, 2003 -- U

  15. Quantum Capacities of Channels with small Environment

    E-Print Network [OSTI]

    Michael M. Wolf; David Perez-Garcia

    2006-07-11T23:59:59.000Z

    We investigate the quantum capacity of noisy quantum channels which can be represented by coupling a system to an effectively small environment. A capacity formula is derived for all cases where both system and environment are two-dimensional--including all extremal qubit channels. Similarly, for channels acting on higher dimensional systems we show that the capacity can be determined if the channel arises from a sufficiently small coupling to a qubit environment. Extensions to instances of channels with larger environment are provided and it is shown that bounds on the capacity with unconstrained environment can be obtained from decompositions into channels with small environment.

  16. NAIHC Convention and Trade Show

    Broader source: Energy.gov [DOE]

    The National American Indian Housing Council's (NAIHC) most longstanding Annual Event, the 39th Annual NAIHC Convention and Trade Show is an opportunity to learn about tribal housing, attend...

  17. Managing Beef Cattle for Show

    E-Print Network [OSTI]

    Herd, Dennis B.; Boleman, Chris; Boleman, Larry L.

    2001-11-16T23:59:59.000Z

    in show diets because of its rapid digestion and tendency to cause acido- sis (see the section on health). Oats are excellent for growth and development of steers or heifers. A mixture similar in nutrient content to oats can be formulated with a high...

  18. Process tomography for unitary quantum channels

    SciTech Connect (OSTI)

    Gutoski, Gus [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada)] [Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2L 2Y5 (Canada); Johnston, Nathaniel [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)] [Institute for Quantum Computing, University of Waterloo, Waterloo, Ontario N2L 3G1 (Canada)

    2014-03-15T23:59:59.000Z

    We study the number of measurements required for quantum process tomography under prior information, such as a promise that the unknown channel is unitary. We introduce the notion of an interactive observable and we show that any unitary channel acting on a d-level quantum system can be uniquely identified among all other channels (unitary or otherwise) with only O(d{sup 2}) interactive observables, as opposed to the O(d{sup 4}) required for tomography of arbitrary channels. This result generalizes to the problem of identifying channels with at most q Kraus operators, and slight improvements can be obtained if we wish to identify such a channel only among unital channels or among other channels with q Kraus operators. These results are proven via explicit construction of large subspaces of Hermitian matrices with various conditions on rank, eigenvalues, and partial trace. Our constructions are built upon various forms of totally nonsingular matrices.

  19. Excitation-energy dependence of the mechanism for two-photon ionization of liquid H2O and D2O from 8.3to12.4eV

    E-Print Network [OSTI]

    Elles, Christopher G.; Jailaubekov, Askat E.; Crowell, Robert A.; Bradforth, Stephen E.

    2006-07-28T23:59:59.000Z

    or gener- ate dangerous amounts of hydrogen gas in radioactive waste storage tanks.1 Radiolysis and photolysis experiments pro- vide a window on the underlying chemistry in such systems by revealing information about the important reactions that occur... following ionization in a controlled environment. Each ionization event produces a hydroxyl radical, a hydronium ion, and a solvated electron within the first few picoseconds, as in the case of two-photon ionization. H2O#1;aq#2; + 2h#2;? OH#1;aq#2; + H3O #1...

  20. High-quality polarization entanglement state preparation and manipulation in standard telecommunication channels

    E-Print Network [OSTI]

    F. Kaiser; A. Issautier; L. A. Ngah; O. Danila; H. Herrmann; W. Sohler; A. Martin; S. Tanzilli

    2012-07-16T23:59:59.000Z

    We report a novel and simple approach for generating near-perfect quality polarization entanglement in a fully guided-wave fashion. Both deterministic pair separation into two adjacent telecommunication channels and the paired photons' temporal walk-off compensation are achieved using standard fiber components. Two-photon interference experiments are performed, both for quantitatively demonstrating the relevance of our approach, and for manipulating the produced state between bosonic and fermionic symmetries. The compactness, versatility, and reliability of this configuration makes it a potential candidate for quantum communication applications.

  1. Implications of Channelization and

    E-Print Network [OSTI]

    Gray, Matthew

    patterns #12;3 Dynamic Hydrology of Hardwood Bottomlands Natural hydroperiod is characterized by stochastic · Irrigation · Levees · Oilfield Canals · Channelization Reasons for Channelization · Mainly for agricultural

  2. Construction of Channels (Indiana)

    Broader source: Energy.gov [DOE]

    Permission is required from the Natural Resources Commission is required for the construction or alteration of artificial channels or improved channels of natural watercourses that connect to any...

  3. Search for Dark Matter in Events with Missing Transverse Momentum and a Higgs Boson Decaying to Two Photons in $pp$ Collisions at $\\sqrt{s}=8$ TeV with the ATLAS Detector

    E-Print Network [OSTI]

    ATLAS Collaboration

    2015-01-01T23:59:59.000Z

    Results of a search for new phenomena in events with large missing transverse momentum and a Higgs boson decaying to two photons are reported. Data from proton--proton collisions at a center-of-mass energy of 8 TeV and corresponding to an integrated luminosity of 20.3 fb$^{-1}$ have been collected with the ATLAS detector at the LHC. The observed data are well described by the expected Standard Model backgrounds. Upper limits on the cross section of events with large missing transverse momentum and a Higgs boson candidate are also placed. Exclusion limits are presented for models of physics beyond the Standard Model featuring dark-matter candidates.

  4. Blind Channel Equalization and -Approximation Algorithms

    E-Print Network [OSTI]

    Ye, Yinyu

    Blind Channel Equalization and #15;-Approximation Algorithms #3; Qingyu Li 1 , Er-Wei Bai 1 University of Iowa Iowa City, IA 52242 Abstract In this paper, we show that a blind equalizer can be obtained without using any sta- tistical information on the input by formulating the blind channel equalization

  5. Extending additivity from symmetric to asymmetric channels

    E-Print Network [OSTI]

    Motohisa Fukuda

    2005-08-14T23:59:59.000Z

    We prove a lemma which allows one to extend results about the additivity of the minimal output entropy from highly symmetric channels to a much larger class. A similar result holds for the maximal output $p$-norm. Examples are given showing its use in a variety of situations. In particular, we prove the additivity and the multiplicativity for the shifted depolarising channel.

  6. Hydrodynamics of vegetated channels

    E-Print Network [OSTI]

    Nepf, Heidi

    This paper highlights some recent trends in vegetation hydrodynamics, focusing on conditions within channels and spanning spatial scales from individual blades, to canopies or vegetation patches, to the channel reach. At ...

  7. Simulating a single qubit channel using a mixed state environment

    E-Print Network [OSTI]

    Geetu Narang; Arvind

    2007-03-06T23:59:59.000Z

    We analyze the class of single qubit channels with the environment modeled by a one-qubit mixed state. The set of affine transformations for this class of channels is computed analytically, employing the canonical form for the two-qubit unitary operator. We demonstrate that, 3/8 of the generalized depolarizing channels can be simulated by the one-qubit mixed state environment by explicitly obtaining the shape of the volume occupied by this class of channels within the tetrahedron representing the generalized depolarizing channels. Further, as a special case, we show that the two-Pauli Channel cannot be simulated by a one-qubit mixed state environment.

  8. Remark on the additivity conjecture for the quantum depolarizing channel

    E-Print Network [OSTI]

    G. G. Amosov

    2005-09-11T23:59:59.000Z

    We consider bistochastic quantum channels generated by unitary representations of the discret group. The proof of the additivity conjecture for the quantum depolarizing channel $\\Phi$ based on the decreasing property of the relative entropy is given. We show that the additivity conjecture is true for the channel $\\Xi =\\Psi \\circ \\Phi $, where $\\Psi $ is the phase damping.

  9. Irregular Turbo Codes in Block-Fading Channels

    E-Print Network [OSTI]

    Kraidy, Ghassan M; Fàbregas, Albert Guillén i

    2010-01-01T23:59:59.000Z

    We study irregular binary turbo codes over non-ergodic block-fading channels. We first propose an extension of channel multiplexers initially designed for regular turbo codes. We then show that, using these multiplexers, irregular turbo codes that exhibit a small decoding threshold over the ergodic Gaussian-noise channel perform very close to the outage probability on block-fading channels, from both density evolution and finite-length perspectives.

  10. Channelization architecture for wide-band slow light in atomic vapors

    E-Print Network [OSTI]

    Zachary Dutton; Mark Bashkansky; Michael Steiner; John Reintjes

    2005-10-20T23:59:59.000Z

    We propose a ``channelization'' architecture to achieve wide-band electromagnetically induced transparency (EIT) and ultra-slow light propagation in atomic Rb-87 vapors. EIT and slow light are achieved by shining a strong, resonant ``pump'' laser on the atomic medium, which allows slow and unattenuated propagation of a weaker ``signal'' beam, but only when a two-photon resonance condition is satisfied. Our wideband architecture is accomplished by dispersing a wideband signal spatially, transverse to the propagation direction, prior to entering the atomic cell. When particular Zeeman sub-levels are used in the EIT system, then one can introduce a magnetic field with a linear gradient such that the two-photon resonance condition is satisfied for each individual frequency component. Because slow light is a group velocity effect, utilizing differential phase shifts across the spectrum of a light pulse, one must then introduce a slight mismatch from perfect resonance to induce a delay. We present a model which accounts for diffusion of the atoms in the varying magnetic field as well as interaction with levels outside the ideal three-level system on which EIT is based. We find the maximum delay-bandwidth product decreases with bandwidth, and that delay-bandwidth product ~1 should be achievable with bandwidth ~50 MHz (~5 ns delay). This is a large improvement over the ~1 MHz bandwidths in conventional slow light systems and could be of use in signal processing applications.

  11. Quantum Channel Capacities

    E-Print Network [OSTI]

    Graeme Smith

    2010-07-16T23:59:59.000Z

    A quantum communication channel can be put to many uses: it can transmit classical information, private classical information, or quantum information. It can be used alone, with shared entanglement, or together with other channels. For each of these settings there is a capacity that quantifies a channel's potential for communication. In this short review, I summarize what is known about the various capacities of a quantum channel, including a discussion of the relevant additivity questions. I also give some indication of potentially interesting directions for future research.

  12. Athermalized channeled spectropolarimeter enhancement.

    SciTech Connect (OSTI)

    Jones, Julia Craven; Way, Brandyn Michael; Mercier, Jeffrey Alan; Hunt, Jeffery P.

    2013-09-01T23:59:59.000Z

    Channeled spectropolarimetry can measure the complete polarization state of light as a function of wavelength. Typically, a channeled spectropolarimeter uses high order retarders made of uniaxial crystal to amplitude modulate the measured spectrum with the spectrally-dependent Stokes polarization information. A primary limitation of conventional channeled spectropolarimeters is related to the thermal variability of the retarders. Thermal variation often forces frequent system recalibration, particularly for field deployed systems. However, implementing thermally stable retarders, made of biaxial crystal, results in an athermal channeled spectropolarimeter that relieves the need for frequent recalibration. This report presents experimental results for an anthermalized channeled spectropolarimeter prototype produced using potassium titanyl phosphate. The results of this prototype are compared to the current thermal stabilization state of the art. Finally, the application of the technique to the thermal infrared is studied, and the athermalization concept is applied to an infrared imaging spectropolarimeter design.

  13. DOE Booth Presentations From Grainger Show 2015

    Broader source: Energy.gov [DOE]

    DOE hosted its solid-state lighting informational booth February 16–18 at the annual Grainger Show in Orlando, FL. With over 17,000 attendees and over 750 exhibitors, the show gathered a wide range of Grainger customers—from universities to large hotel chains as well as Grainger team members to learn the latest about LED lighting.

  14. Fractional channel multichannel analyzer

    DOE Patents [OSTI]

    Brackenbush, L.W.; Anderson, G.A.

    1994-08-23T23:59:59.000Z

    A multichannel analyzer incorporating the features of the present invention obtains the effect of fractional channels thus greatly reducing the number of actual channels necessary to record complex line spectra. This is accomplished by using an analog-to-digital converter in the asynchronous mode, i.e., the gate pulse from the pulse height-to-pulse width converter is not synchronized with the signal from a clock oscillator. This saves power and reduces the number of components required on the board to achieve the effect of radically expanding the number of channels without changing the circuit board. 9 figs.

  15. Dangerous Bodies: Freak Shows, Expression, and Exploitation

    E-Print Network [OSTI]

    Fordham, Brigham A.

    2007-01-01T23:59:59.000Z

    Dangerous Bodies: Freak Shows, Expression, and ExploitationR.I. GEN. LAWS § 11-9-1. DANGEROUS BODIES Rhode Island does161 Id. Id. 165 id. 166 Id. DANGEROUS BODIES This argument

  16. Side-Channel Oscilloscope

    E-Print Network [OSTI]

    Chaudhuri, Sumanta

    2011-01-01T23:59:59.000Z

    Side-Channel Analysis used for codebreaking could be used constructively as a probing tool for internal gates in integrated circuits. This paper outlines basic methods and mathematics for that purpose

  17. Distributed Precoding for MISO Interference Channels with Channel Mean Feedback

    E-Print Network [OSTI]

    Ulukus, Sennur

    Distributed Precoding for MISO Interference Channels with Channel Mean Feedback: Algorithms precoding algorithms for multiple-input single-output (MISO) interference channels, where each trans- mitter- antenna wireless interference channels [5]-[7]. For multiple- input single-output (MISO) interference

  18. On Weyl channels being covariant with respect to the maximum commutative group of unitaries

    E-Print Network [OSTI]

    G. G. Amosov

    2006-08-10T23:59:59.000Z

    We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the "two-Pauli" channel as well. Then, we show that our estimation of the output entropy for a tensor product of the phase damping channel and the identity channel based upon the decreasing property of the relative entropy allows to prove the additivity conjecture for the minimal output entropy for the quantum depolarizing channel in any prime dimesnsion and for the "two Pauli" channel in the qubit case.

  19. On Weyl channels being covariant with respect to the maximum commutative group of unitaries

    SciTech Connect (OSTI)

    Amosov, Grigori G. [Department of Higher Mathematics, Moscow Institute of Physics and Technology, Dolgoprudny 141700 (Russian Federation)

    2007-01-15T23:59:59.000Z

    We investigate the Weyl channels being covariant with respect to the maximum commutative group of unitary operators. This class includes the quantum depolarizing channel and the 'two-Pauli' channel as well. Then, we show that our estimation of the output entropy for a tensor product of the phase damping channel and the identity channel based upon the decreasing property of the relative entropy allows to prove the additivity conjecture for the minimal output entropy for the quantum depolarizing channel in any prime dimension and for the two-Pauli channel in the qubit case.

  20. Downstream variations in the width of bedrock channels David R. Montgomery and Karen B. Gran

    E-Print Network [OSTI]

    Montgomery, David R.

    Downstream variations in the width of bedrock channels David R. Montgomery and Karen B. Gran the Mokelumne River show that bedrock channel width decreases substantially downstream at the contact between show systematic channel widening after flood flows and debris flow impacts. We conclude that downstream

  1. Channel plate for DNA sequencing

    DOE Patents [OSTI]

    Douthart, R.J.; Crowell, S.L.

    1998-01-13T23:59:59.000Z

    This invention is a channel plate that facilitates data compaction in DNA sequencing. The channel plate has a length, a width and a thickness, and further has a plurality of channels that are parallel. Each channel has a depth partially through the thickness of the channel plate. Additionally an interface edge permits electrical communication across an interface through a buffer to a deposition membrane surface. 15 figs.

  2. MEMS in microfluidic channels.

    SciTech Connect (OSTI)

    Ashby, Carol Iris Hill; Okandan, Murat; Michalske, Terry A.; Sounart, Thomas L.; Matzke, Carolyn M.

    2004-03-01T23:59:59.000Z

    Microelectromechanical systems (MEMS) comprise a new class of devices that include various forms of sensors and actuators. Recent studies have shown that microscale cantilever structures are able to detect a wide range of chemicals, biomolecules or even single bacterial cells. In this approach, cantilever deflection replaces optical fluorescence detection thereby eliminating complex chemical tagging steps that are difficult to achieve with chip-based architectures. A key challenge to utilizing this new detection scheme is the incorporation of functionalized MEMS structures within complex microfluidic channel architectures. The ability to accomplish this integration is currently limited by the processing approaches used to seal lids on pre-etched microfluidic channels. This report describes Sandia's first construction of MEMS instrumented microfluidic chips, which were fabricated by combining our leading capabilities in MEMS processing with our low-temperature photolithographic method for fabricating microfluidic channels. We have explored in-situ cantilevers and other similar passive MEMS devices as a new approach to directly sense fluid transport, and have successfully monitored local flow rates and viscosities within microfluidic channels. Actuated MEMS structures have also been incorporated into microfluidic channels, and the electrical requirements for actuation in liquids have been quantified with an elegant theory. Electrostatic actuation in water has been accomplished, and a novel technique for monitoring local electrical conductivities has been invented.

  3. Entanglement-Saving Channels

    E-Print Network [OSTI]

    Ludovico Lami; Vittorio Giovannetti

    2015-05-03T23:59:59.000Z

    The set of Entanglement Saving (ES) quantum channels is introduced and characterized. These are completely positive, trace preserving transformations which when acting locally on a bipartite quantum system initially prepared into a maximally entangled configuration, preserve its entanglement even when applied an arbitrary number of times. In other words, a quantum channel $\\psi$ is said to be ES if its powers $\\psi^n$ are not entanglement-breaking for all integers $n$. We also characterize the properties of the Asymptotic Entanglement Saving (AES) maps. These form a proper subset of the ES channels that is constituted by those maps which, not only preserve entanglement for all finite $n$, but which also sustain an explicitly not null level of entanglement in the asymptotic limit~$n\\rightarrow \\infty$. Structure theorems are provided for ES and for AES maps which yield an almost complete characterization of the former and a full characterization of the latter.

  4. Alpha Channeling in Rotating Plasma with Stationary Waves

    SciTech Connect (OSTI)

    A. Fetterman and N.J. Fisch

    2010-02-15T23:59:59.000Z

    An extension of the alpha channeling effect to supersonically rotating mirrors shows that the rotation itself can be driven using alpha particle energy. Alpha channeling uses radiofrequency waves to remove alpha particles collisionlessly at low energy. We show that stationary magnetic fields with high n? can be used for this purpose, and simulations show that a large fraction of the alpha energy can be converted to rotation energy.

  5. Conductive Channel for Energy Transmission

    SciTech Connect (OSTI)

    Apollonov, Victor V. [A.M. Prokhorov General Physics Institute, Vavilov Str. 38, Moscow, 119991 (Russian Federation)

    2011-11-10T23:59:59.000Z

    For many years the attempts to create conductive channels of big length were taken in order to study the upper atmosphere and to settle special tasks, related to energy transmission. There upon the program of creation of 'Impulsar' represents a great interest, as this program in a combination with high-voltage high repetition rate electrical source can be useful to solve the above mentioned problems (N. Tesla ideas for the days of high power lasers). The principle of conductive channel production can be shortly described as follows. The 'Impulsar' - laser jet engine vehicle - propulsion take place under the influence of powerful high repetition rate pulse-periodic laser radiation. In the experiments the CO{sub 2}-laser and solid state Nd:YAG laser systems had been used. Active impulse appears thanks to air breakdown (<30 km) or to the breakdown of ablated material on the board (>30 km), placed in the vicinity of the focusing mirror-acceptor of the breakdown waves. With each pulse of powerful laser the device rises up, leaving a bright and dense trace of products with high degree of ionization and metallization by conductive nano-particles due to ablation. Conductive dust plasma properties investigation in our experiments was produced by two very effective approaches: high power laser controlled ablation and by explosion of wire. Experimental and theoretical results of conductive canal modeling will be presented. The estimations show that with already experimentally demonstrated figures of specific thrust impulse the lower layers of the Ionosphere can be reached in several ten seconds that is enough to keep the high level of channel conductivity and stability with the help of high repetition rate high voltage generator. Some possible applications for new technology are highlighted.

  6. Channeling through Bent Crystals

    SciTech Connect (OSTI)

    Mack, Stephanie; /Ottawa U. /SLAC

    2012-09-07T23:59:59.000Z

    Bent crystals have demonstrated potential for use in beam collimation. A process called channeling is when accelerated particle beams are trapped by the nuclear potentials in the atomic planes within a crystal lattice. If the crystal is bent then the particles can follow the bending angle of the crystal. There are several different effects that are observed when particles travel through a bent crystal including dechanneling, volume capture, volume reflection and channeling. With a crystal placed at the edge of a particle beam, part of the fringe of the beam can be deflected away towards a detector or beam dump, thus helping collimate the beam. There is currently FORTRAN code by Igor Yazynin that has been used to model the passage of particles through a bent crystal. Using this code, the effects mentioned were explored for beam energy that would be seen at the Facility for Advanced Accelerator Experimental Tests (FACET) at a range of crystal orientations with respect to the incoming beam. After propagating 5 meters in vacuum space past the crystal the channeled particles were observed to separate from most of the beam with some noise due to dechanneled particles. Progressively smaller bending radii, with corresponding shorter crystal lengths, were compared and it was seen that multiple scattering decreases with the length of the crystal therefore allowing for cleaner detection of the channeled particles. The input beam was then modified and only a portion of the beam sent through the crystal. With the majority of the beam not affected by the crystal, most particles were not deflected and after propagation the channeled particles were seen to be deflected approximately 5mm. After a portion of the beam travels through the crystal, the entire beam was then sent through a quadrupole magnet, which increased the separation of the channeled particles from the remainder of the beam to a distance of around 20mm. A different code, which was developed at SLAC, was used to create an angular profile plot which was compared to what was produced by Yazynin's code for a beam with no multiple scattering. The results were comparable, with volume reflection and channeling effects observed and the range of crystal orientations at which volume reflection is seen was about 1 mrad in both simulations.

  7. Energy Blog | Department of Energy

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

    A simulation of the two-photon channel shows what ATLAS sees when the decay of a Higgs boson results in the production of two gamma rays. The blue beads indicate intermediate...

  8. Degenerate Quantum Codes for Pauli Channels

    E-Print Network [OSTI]

    Graeme Smith; John A. Smolin

    2006-12-23T23:59:59.000Z

    A striking feature of quantum error correcting codes is that they can sometimes be used to correct more errors than they can uniquely identify. Such degenerate codes have long been known, but have remained poorly understood. We provide a heuristic for designing degenerate quantum codes for high noise rates, which is applied to generate codes that can be used to communicate over almost any Pauli channel at rates that are impossible for a nondegenerate code. The gap between nondegenerate and degenerate code performance is quite large, in contrast to the tiny magnitude of the only previous demonstration of this effect. We also identify a channel for which none of our codes outperform the best nondegenerate code and show that it is nevertheless quite unlike any channel for which nondegenerate codes are known to be optimal.

  9. Wideband Fading Channels With Feedback

    E-Print Network [OSTI]

    Borade, Shashi

    The Rayleigh flat fading channel at low SNR is considered. With full channel state information (CSI) at the transmitter and receiver, its capacity is shown to be essentially SNR log(1SNR) nats/symbol, as SNR goes to zero. ...

  10. Local heat transfer in rotating smooth and ribbed two-pass square channels with three channel orientations

    SciTech Connect (OSTI)

    Dutta, S. [Univ. of South Carolina, Columbia, SC (United States); Han, J.C. [Texas A& M Univ., College Station, TX (United States)

    1996-08-01T23:59:59.000Z

    This paper presents experimental heat transfer results in a two-pass square channel with smooth and ribbed surfaces. The ribs are placed in a staggered half-V fashion with the rotation orthogonal to the channel axis. The channel orientation varies with respect to the rotation plane. A change in the channel orientation about the rotating frame causes a change in the secondary flow structure and associated flow and turbulence distribution. Consequently, the heat transfer coefficient from the individual surfaces of the two-pass square channel changes. The effects of rotation number on local Nusselt number ratio distributions are presented. Heat transfer coefficients with ribbed surfaces show different characteristics in rotation number dependency from those with smooth surfaces. Results show that staggered half-V ribs mostly have higher heat transfer coefficients than those with 90 and 60 deg continuous ribs. 16 refs., 10 figs.

  11. VAX CAMAC channel

    SciTech Connect (OSTI)

    Nelson, D.J.; Breidenbach, M.; Granieri, C.D.; Grund, J.E.; Patrick, J.F.; Weaver, L.J.

    1980-10-01T23:59:59.000Z

    A new generation CAMAC System has been developed for the Mark II Detector at SLAC's PEP storage ring. This flexible system can efficiently transfer data between a host computer and a very large set of CAMAC data acquisition and control modules. A bipolar microprocessor operates as a Channel interface by supervising the CAMAC system and minimizing the host computer's work. This programmable channel couples the host to a set of System Crates; each System Crate houses Branch Drivers that can directly control a set of crates or communicate over differential parallel highways to Branch Receivers for control of distant crates. A coherent software package integrates the high level programs, system driver level programs, and microcode control of the system.

  12. Sensitivity of Gaussian Channel Capacity and ate-Distortion Function to nonGaussian Contamination

    E-Print Network [OSTI]

    Verdú, Sergio

    Sensitivity of Gaussian Channel Capacity and ate-Distortion Function to nonGaussian Contamination-Gaussian contaminating noise. Although the ca- pacity of such channels cannot be evaluated in general, we analyze the decrease in capacity, or sensitivity of the channel capacity to the weak contaminating noise. We show

  13. Capacity Theorems for Relay Channels with ISI Ninoslav Marina, Aleksandar Kavcic and N. Thomas Gaarder

    E-Print Network [OSTI]

    Kavcic, Aleksandar

    Capacity Theorems for Relay Channels with ISI Ninoslav Marina, Aleksandar Kavci´c and N. Thomas-length intersymbol interference (ISI). For such channels, we show that the decode-and-forward strategy achieves the destination node to the relay node is an instance of a degraded relay channel with ISI, and observe

  14. Channel | Open Energy Information

    Open Energy Info (EERE)

    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 You are beingZealand JumpConceptual Model, click here.Telluric Survey asWest,CEI JumpChandradeep Solar PvtChannel Jump to:

  15. Control power in perfect controlled teleportation via partially entangled channels

    E-Print Network [OSTI]

    Xi-Han Li; Shohini Ghose

    2014-10-05T23:59:59.000Z

    We analyze and evaluate perfect controlled teleportation via three-qubit entangled channels from the point of view of the controller. The key idea in controlled teleportation is that the teleportation is performed only with the participation of the controller. We calculate a quantitative measure of the controller's power and establish a lower bound on the control power required for controlled teleportation. We show that the maximally entangled GHZ state is a suitable channel for controlled teleportation of arbitrary single qubits - the controller's power meets the bound and the teleportation fidelity without the controller's permission is no better than the fidelity of a classical channel. We also construct partially entangled channels that exceed the bound for controlled teleportation of a restricted set of states called the equatorial states. We calculate the minimum entanglement required in these channels to exceed the bound. Moreover, we find that in these restricted controlled teleportation schemes, the partially entangled channels can outperform maximally entangled channels with respect to the controller's power. Our results provide a new perspective on controlled teleportation schemes and are of practical interest since we propose useful partially entangled channels.

  16. Viscous lock-exchange in rectangular channels

    E-Print Network [OSTI]

    Jerome Martin; Nicole Rakotomalala; Laurent Talon; Dominique Salin

    2010-11-29T23:59:59.000Z

    In a viscous lock-exchange gravity current, which describes the reciprocal exchange of two fluids of different densities in a horizontal channel, the front between two Newtonian fluids spreads as the square root of time. The resulting diffusion coefficient reflects the competition between the buoyancy driving effect and the viscous damping, and depends on the geometry of the channel. This lock-exchange diffusion coefficient has already been computed for a porous medium, a 2D Stokes flow between two parallel horizontal boundaries separated by a vertical height, H, and, recently, for a cylindrical tube. In the present paper, we calculate it, analytically, for a rectangular channel (horizontal thickness b, vertical height, H) of any aspect ratio (H/b) and compare our results with experiments in horizontal rectangular channels for a wide range of aspect ratios (1/10-10). We also discuss the 2D Stokes-Darcy model for flows in Hele-Shaw cells and show that it leads to a rather good approximation, when an appropriate Brinkman correction is used.

  17. Mirrored serpentine flow channels for fuel cell

    DOE Patents [OSTI]

    Rock, Jeffrey Allan (Rochester, NY)

    2000-08-08T23:59:59.000Z

    A PEM fuel cell having serpentine flow field channels wherein the input/inlet legs of each channel border the input/inlet legs of the next adjacent channels in the same flow field, and the output/exit legs of each channel border the output/exit legs of the next adjacent channels in the same flow field. The serpentine fuel flow channels may be longer, and may contain more medial legs, than the serpentine oxidant flow channels.

  18. Controlled remote state preparation via partially entangled quantum channel

    E-Print Network [OSTI]

    Chun Wang; Zhi Zeng; Xi-Han Li

    2014-12-30T23:59:59.000Z

    We propose two controlled remote state preparation protocols via partially entangled channels. One prepares a single-qubit state and the other prepares a two-qubit state. Different from other controlled remote state preparation schemes which also utilize partially entangled channels, neither auxiliary qubits nor two-qubit unitary transformations are required in our schemes and the success probabilities are independent of the coefficients of the quantum channel. The success probabilities are 50% and 25% for arbitrary single-qubit states and two-qubit states, respectively. We also show that the success probabilities can reach 100% for restricted classes of states.

  19. Quantum Gaussian Channels with Additive Correlated Classical Noise

    E-Print Network [OSTI]

    Giovanna Ruggeri; Stefano Mancini

    2006-09-04T23:59:59.000Z

    We provide a model to study memory effects in quantum Gaussian channels with additive classical noise over an arbitrary number of uses. The correlation among different uses is introduced by contiguous two-mode interactions. Numerical results for few modes are presented. They confirm the possibility to enhance the classical information rate with the aid of entangled inputs, and show a likely asymptotic behavior that should lead to the full capacity of the channel.

  20. Muon Cooling Channels Eberhard Keil

    E-Print Network [OSTI]

    Keil, Eberhard

    Muon Cooling Channels Eberhard Keil Katharinenstr. 17, DE-10711 Berlin, Germany Abstract Parameters of muon cooling channels are discussed that achieve cooling of a muon beam from initial to final emittances in all three degrees of freedom in a given length. Published theories of ionisation cooling yield

  1. Jet impingement heat transfer in two-pass rotating rectangular channels 

    E-Print Network [OSTI]

    Zhang, Yuming

    1996-01-01T23:59:59.000Z

    compared with previously reported correlations. The pressure distributions show that the major effect on heat transfer is the jet impingement in the beginning of the channel and the cross flow at the end of the channel. The results also show that heat...

  2. Bargaining and the MISO Interference Channel

    E-Print Network [OSTI]

    Nokleby, Matthew; Swindlehurst, A. Lee

    2009-01-01T23:59:59.000Z

    the pareto boundary for the MISO interference channel,” IEEEinterference in the Gaussian MISO broadcast channel,” inOn maximizing the sum network MISO broadcast capacity,” in

  3. Broadcasting Gaussian Sources Over Gaussian Channels

    E-Print Network [OSTI]

    Gao, Yang

    2012-01-01T23:59:59.000Z

    Channel . . . . . . . . . . Power Loss for the Gaussianbroadcast channel, the power loss of separate coding is alsois to analyze the power loss for the Gaussian case. We

  4. Electrochemomechanical Energy Conversion in Nanofluidic Channels

    E-Print Network [OSTI]

    Yang, Peidong

    Electrochemomechanical Energy Conversion in Nanofluidic Channels Hirofumi Daiguji,*, Peidong Yang the height of a nanofluidic channel containing surface charge, a unipolar solution of counterions

  5. Joint Turbo Channel Detection and RLL Decoding for (1, 7) Coded Partial Response Recording Channels Zhao Fang IBM Global Services

    E-Print Network [OSTI]

    George Mathew; B. Farhang-boroujeny

    Abstract — Runlength limited (RLL) codes are essential in recording systems for minimizing distortions and maintaining bit synchronization. In this paper, we investigate the application of turbo codes on RLL (1, 7) coded partial response equalized recording channels. We propose a ‘combined trellis ’ approach for doing ‘soft-in soft-out ’ (SISO) channel detection and RLL decoding jointly. This approach makes the implementation of turbo equalization easier since it eliminates the need for a ‘SISO RLL encoder ’ in the feedback path from turbo decoder to channel detector. Simulation studies on magnetic recording channels show that our approach provides a coding gain of about 4 dB compared to Viterbi detection at 10 ?6 bit error rate. I.

  6. Opportunistic Power Control for Multi-Carrier Interference Channels

    E-Print Network [OSTI]

    Javan, Mohammad R

    2011-01-01T23:59:59.000Z

    We propose a new method for opportunistic power control in multi-carrier interference channels for delay-tolerant data services. In doing so, we utilize a game theoretic framework with novel constraints, where each user tries to maximize its utility in a distributed and opportunistic manner, while satisfying the game's constraints by adapting its transmit power to its channel. In this scheme, users transmit with more power on good sub-channels and do the opposite on bad sub-channels. In this way, in addition to the allocated power on each sub-channel, the total power of all users also depends on channel conditions. Since each user's power level depends on power levels of other users, the game belongs to the \\emph{generalized} Nash equilibrium (GNE) problems, which in general, is hard to analyze. We show that the proposed game has a GNE, and derive the sufficient conditions for its uniqueness. Besides, we propose a new pricing scheme for maximizing each user's throughput in an opportunistic manner under its to...

  7. Energy Innovation Hub Report Shows Philadelphia-area Building...

    Office of Environmental Management (EM)

    Innovation Hub Report Shows Philadelphia-area Building Retrofits Could Support 23,500 Jobs Energy Innovation Hub Report Shows Philadelphia-area Building Retrofits Could Support...

  8. EMERGING TECHNOLOGIES Two-photon excitation chlorophyll fluorescence lifetime imaging

    E-Print Network [OSTI]

    Qu, Jianan

    at higher Cd concentration was clearly identified. The decay of chlorophyll fluorescence extracted from) toxicity Abbreviations Cd Cadmium PS Photosystem LHCII Light-harvesting complex II PAM Pulse and Computer Engineering, Hong Kong University of Science and Technology (HKUST), Clear Water Bay, Kowloon

  9. Diffraction in Two-Photon Collisions at TESLA

    E-Print Network [OSTI]

    A. De Roeck; R. Engel; A. Rostovtsev

    1997-10-15T23:59:59.000Z

    In this article we discuss the possibility to measure diffraction dissociation in collisions of real and weakly virtual photons at a 500 GeV e+e- linear collider.

  10. Two-photon production of charged pion and kaon pairs

    E-Print Network [OSTI]

    Baringer, Philip S.

    1994-09-01T23:59:59.000Z

    calorizneter com- posed of 7800 thallium-doped cesium iodide (CsI) crys- tals. The barrel section of the CsI calorimeter forms an integral part of this analysis as the fine tower segmenta- tion allows for particle discrimination based on an analy- sis of shower... as the contamination from anni- hilation events, the two tracks must pass an acolinearity requirement: the angle between the two tracks must be more than 100 mrad away from back to back. Finally, the two tracks are required to project to well-understood regions...

  11. Hard two photon processes ??--> M_2 M_1 in QCD

    E-Print Network [OSTI]

    Victor L. Chernyak

    2012-12-06T23:59:59.000Z

    A short review of leading term QCD predictions vs those of the handbag model for large angle cross sections \\gamma\\gamma --> P_2 P_1 (P is the pseudoscalar meson \\pi^{\\pm,o}, K^{\\pm,o}, \\eta), and for \\gamma\\gamma --> V_2 V_1 (V is the neutral vector meson \\rho^o, \\omega, \\phi), in comparison with Belle Collaboration measuments

  12. TwoPhoton Absorption (TPA) Liquid Crystal Institute

    E-Print Network [OSTI]

    Palffy-Muhoray, Peter

    , actually results in a larger resolution spot. #12; 3D Microfabrication http://npm.creol.ucf.edu/3DM

  13. New bounding techniques for channel codes over quasi-static fading channels

    E-Print Network [OSTI]

    Hu, Jingyu

    2005-04-01T23:59:59.000Z

    This thesis is intended to provide several new bounding techniques for channel codes over quasi-static fading channels (QSFC). This type of channel has drawn more and more attention recently with the demanding need for higher capacity and more...

  14. 6 Equalization of Channels with ISI Many practical channels are bandlimited and linearly distort the

    E-Print Network [OSTI]

    Pulfrey, David L.

    244 6 Equalization of Channels with ISI Many practical channels are bandlimited and linearly distort the transmit signal. In this case, the resulting ISI channel has to be equalized for reliable

  15. On Duality in the MISO Interference Channel Francesco Negro, Irfan Ghauri, Dirk T.M. Slock

    E-Print Network [OSTI]

    Gesbert, David

    On Duality in the MISO Interference Channel Francesco Negro, Irfan Ghauri, Dirk T.M. Slock Infineon in a multi-input single- output (MISO) interference channel (IFC) and its dual SIMO with linear transmit (Tx for the IFC. We show that SINR duality under the sum power constraint nevertheless holds in the MISO IFC

  16. Gating Currents from Kv7 Channels Carrying Neuronal Hyperexcitability Mutations in the Voltage-Sensing Domain

    E-Print Network [OSTI]

    Bezanilla, Francisco

    unable to provide a detailed assessment of the structural rearrangements underlying channel gating.2 channels both functionally and structurally, were used for these experiments. The data obtained showed activation of gating-pore currents at depolarized potentials. These results reveal that distinct molecular

  17. PHYSICAL REVIEW B 84, 144511 (2011) Rectification of vortex motion in a circular ratchet channel

    E-Print Network [OSTI]

    Plourde, Britton L. T.

    2011-01-01T23:59:59.000Z

    PHYSICAL REVIEW B 84, 144511 (2011) Rectification of vortex motion in a circular ratchet channel N and induces a net vortex flow without any unbiased external drive, i.e., the ratchet effect. We show containing a single weak-pinning circular ratchet channel in a Corbino geometry and observed a substantial

  18. Secret-Key Agreement over a Non-Coherent Block-Fading MIMO Wiretap Channel

    E-Print Network [OSTI]

    Khisti, Ashish

    Secret-Key Agreement over a Non-Coherent Block-Fading MIMO Wiretap Channel Mattias Andersson. Dept., Univ. of Toronto, Toronto, ON, Canada email: akhisti@comm.utoronto.ca Abstract--We study secret. In this case we show that secret-key agreement is still possible by using the wireless channel for discussion

  19. Theoretical Estimates of HVAC Duct Channel Capacity for High-Speed Internet Access

    E-Print Network [OSTI]

    Stancil, Daniel D.

    Theoretical Estimates of HVAC Duct Channel Capacity for High-Speed Internet Access Ariton E. Xhafa-conditioning (HVAC) ducts based on multi-carrier transmission that uses M-QAM mod- ulation and measured channel- flections in HVAC ducts). Our work also shows that data rates in excess of 300 Mbps are possible over

  20. Side-Channel Resistance Evaluation of a Neural Network Based Lightweight Cryptography Scheme

    E-Print Network [OSTI]

    Side-Channel Resistance Evaluation of a Neural Network Based Lightweight Cryptography Scheme Marc Email: koch@esa.cs.tu-darmstadt.de Abstract-- Side-channel attacks have changed the design of secure such as, e.g., AES, show the need to consider these aspects to build more resistant cryptographic systems

  1. Interference Channel with State Information 

    E-Print Network [OSTI]

    Zhang, Lili

    2012-10-19T23:59:59.000Z

    with State Information. (August 2012) Lili Zhang, B.S., University of Science and Technology of China; M.S., University of Science and Technology of China Chair of Advisory Committee: Shuguang Cui In this dissertation, we study the state-dependent two... Fig. 2.: The interference channel with state information non-causally known at both transmitters. channel is assumed to be memoryless, i.e., p(yn1 , yn2 |xn1 , xn2 , sn) = n? i=1 p(y1i, y2i|x1i, x2i, si), where i is the element index for each...

  2. Multilevel trellis coded modulation for the fading channel

    E-Print Network [OSTI]

    Tung, Chien-Cheng

    1993-01-01T23:59:59.000Z

    Trellis coded modulation (TCM) has been applied to the fading channel recently [11-[3]. Among these articles, Divsalar and Simon showed in their papers that the length of the shortest error path and the product of the branch distance along the path...

  3. The generation of shared cryptographic keys through channel impulse response estimation at 60 GHz.

    SciTech Connect (OSTI)

    Young, Derek P.; Forman, Michael A.; Dowdle, Donald Ryan

    2010-09-01T23:59:59.000Z

    Methods to generate private keys based on wireless channel characteristics have been proposed as an alternative to standard key-management schemes. In this work, we discuss past work in the field and offer a generalized scheme for the generation of private keys using uncorrelated channels in multiple domains. Proposed cognitive enhancements measure channel characteristics, to dynamically change transmission and reception parameters as well as estimate private key randomness and expiration times. Finally, results are presented on the implementation of a system for the generation of private keys for cryptographic communications using channel impulse-response estimation at 60 GHz. The testbed is composed of commercial millimeter-wave VubIQ transceivers, laboratory equipment, and software implemented in MATLAB. Novel cognitive enhancements are demonstrated, using channel estimation to dynamically change system parameters and estimate cryptographic key strength. We show for a complex channel that secret key generation can be accomplished on the order of 100 kb/s.

  4. 2015 ACI National Home Performance Conference and Trade Show...

    Office of Environmental Management (EM)

    2015 ACI National Home Performance Conference and Trade Show 2015 ACI National Home Performance Conference and Trade Show May 4, 2015 9:00AM EDT to May 7, 2015 5:0...

  5. New Geothermal Prospects in the Western United States Show Promise...

    Energy Savers [EERE]

    New Geothermal Prospects in the Western United States Show Promise New Geothermal Prospects in the Western United States Show Promise February 27, 2013 - 2:21pm Addthis New...

  6. Sandia National Laboratories: New Material Tests Show Biaxial...

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

    Material Tests Show Biaxial Laminate Creep Is Important for Large Wind-Turbine Blades New Material Tests Show Biaxial Laminate Creep Is Important for Large Wind-Turbine Blades...

  7. EIGHT CHANNEL PROGRAMMABLE PULSE GENERATOR

    E-Print Network [OSTI]

    Kleinfeld, David

    Master-8 EIGHT CHANNEL PROGRAMMABLE PULSE GENERATOR Operation Manual A.M.P.I. A.M.P.I. 123Uzlel St and the programming simple and easy to learn. Master-8 is an attractive unit and you will enjoy working with its eight -- Modes of operation 11 -- Setting the parameters 13 -- Triggering 14 -- Eight stored paradigms 14

  8. Non-decaying hydrodynamic interactions along narrow channels

    E-Print Network [OSTI]

    Misiunas, Karolis; Lauga, Eric; Lister, John R; Keyser, Ulrich F

    2015-01-01T23:59:59.000Z

    Particle-particle interactions are of paramount importance in every multi-body system as they determine the collective behaviour and coupling strength. Many well-known interactions like electro-static, van der Waals or screened Coulomb, decay exponentially or with negative powers of the particle spacing r. Similarly, hydrodynamic interactions between particles undergoing Brownian motion decay as 1/r in bulk, and are assumed to decay quickly in small channels. Such interactions are ubiquitous in biological and technological systems. Here we confine two particles undergoing Brownian motion in narrow, microfluidic channels and study their coupling through hydrodynamic interactions. Our experiments show that, in contrast to expectations from current theoretical understanding, the hydrodynamic particle-particle interactions are long-range and non-decaying in these channels. This new effect is of fundamental importance for the interpretation of experiments where dense mixtures of particles or molecules diffuse thro...

  9. Flows and mixing in channels with misaligned superhydrophobic walls

    E-Print Network [OSTI]

    Nizkaya, Tatiana V; Zhou, Jiajia; Schmid, Friederike; Vinogradova, Olga I

    2014-01-01T23:59:59.000Z

    Aligned superhydrophobic surfaces with the same texture orientation reduce drag in the channel and generate secondary flows transverse to the direction of the applied pressure gradient. Here we show that a transverse shear, superimposed with the conventional Poiseuille and slip-driven plug flows, can be easily generated by using superhydrophobic channels with misaligned textured surfaces. We propose a general theoretical approach to quantify this transverse flow by introducing the concept of an effective shear tensor. To illustrate its use, we present approximate theoretical solutions and Dissipative Particle Dynamics simulations for striped superhydrophobic channels. Our results demonstrate that the transverse shear leads to complex flow patterns on the length scale of the texture period, which leads to a new mechanism of a passive mixing at low Reynolds number. This vertical mixing occurs at the texture period scale and does not require the contribution of side walls. Our results provide a basis for design ...

  10. Flows and mixing in channels with misaligned superhydrophobic walls

    E-Print Network [OSTI]

    Tatiana V. Nizkaya; Evgeny S. Asmolov; Jiajia Zhou; Friederike Schmid; Olga I. Vinogradova

    2015-03-14T23:59:59.000Z

    Aligned superhydrophobic surfaces with the same texture orientation reduce drag in the channel and generate secondary flows transverse to the direction of the applied pressure gradient. Here we show that a transverse shear can be easily generated by using superhydrophobic channels with misaligned textured surfaces. We propose a general theoretical approach to quantify this transverse flow by introducing the concept of an effective shear tensor. To illustrate its use, we present approximate theoretical solutions and Dissipative Particle Dynamics simulations for striped superhydrophobic channels. Our results demonstrate that the transverse shear leads to complex flow patterns, which provide a new mechanism of a passive vertical mixing at the scale of a texture period. Depending on the value of Reynolds number two different scenarios occur. At relatively low Reynolds number the flow represents a transverse shear superimposed with two co-rotating vortices. For larger Reynolds number these vortices become isolated, by suppressing fluid transport in the transverse direction.

  11. Feedback Capacity of the Compound Channel

    E-Print Network [OSTI]

    Shrader, Brooke E.

    In this work, we find the capacity of a compound finite-state channel (FSC) with time-invariant deterministic feedback. We consider the use of fixed length block codes over the compound channel. Our achievability result ...

  12. Channel incision in Rodeo Creek, Marin County

    E-Print Network [OSTI]

    Bass, Phoebe; Choy, Min

    2004-01-01T23:59:59.000Z

    on the Wetlands of Rodeo Creek in the Marin Headlands,channel. Cross Section 3 Rodeo Creek is 5 ft wide at Cross1.55 ft deep. Here, Rodeo Creek is a small channel running

  13. alfa show improved: Topics by E-print Network

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

    Policy Program Format AZ Town Hall president, Tara Jackson Reisslein, Martin 299 Seismic tomography shows that upwelling beneath Iceland is confined to the upper mantle...

  14. ORISE: Report shows nuclear engineering graduation rates on the...

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

    ORISE report shows nuclear engineering graduation rates on the rise in 2013 Number of graduate degrees expected to remain consistent, but undergraduate degrees could see decrease...

  15. Sandia Energy - Sandia Study Shows Large LNG Fires Hotter but...

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

    Study Shows Large LNG Fires Hotter but Smaller Than Expected Home Infrastructure Security News News & Events Energy Assurance Modeling Modeling & Analysis Analysis Sandia Study...

  16. abeta oligomers show: Topics by E-print Network

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

    Creek showing (Candy and Deep Purple claims) is hosted by Middle Devonian carbonate rocks in the southem Rocky Mountains oi British Columbia. The property lies near the...

  17. Sandia Energy - Biofuels Blend Right In: Researchers Show Ionic...

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

    Biofuels Blend Right In: Researchers Show Ionic Liquids Effective for Pretreating Mixed Blends of Biofuel Feedstocks Home Renewable Energy Energy Transportation Energy Biofuels...

  18. Corrosion and arc erosion in MHD channels

    SciTech Connect (OSTI)

    Rosa, R.J. (Montana State Univ., Bozeman, MT (United States). Dept. of Mechanical Engineering); Pollina, R.J. (Montana State Univ., Bozeman, MT (United States). Dept. of Mechanical Engineering EG and G Energy Measurements, Inc., Las Vegas, NV (United States))

    1992-08-01T23:59:59.000Z

    The problems connected with gas side corrosion for the design of the lA4 (POC) channel hardware are explored and results of gas side wear rate tests in the Textron Mark VII facility are presented. It is shown that the proposed designs meet a 2000 hour lifetime criterion based upon these materials tests. Improvement in cathode lifetime is demonstrated with lower voltage intercathode gaps. The corrosion of these materials is discussed and it is shown how lifetimes are dependent upon gap voltage and average metal temperature. The importance of uniformity of slagging to the durability of the anode wall is demonstrated. The wear mechanism of the anodes in the MHD channel is analyzed. In addition to gas-side corrosion, the results of specific water corrosion tests of sidewall materials are discussed. All of the tests reported here were carried out to confirm the gas-side performance and the manufacturability of anode and sidewall designs and to address questions posed about the durability of tungsten-copper on the waterside. the results of water corrosion tests of the tungsten copper alloy sidewall material are presented to show that with proper control of waterside pH and, if necessary, dissolved oxygen, one can obtain reliable performance with no degradation of heat transfer with this material. The final choice of materials was determined primarily by the outcome of these tests and also by the question of the manufacturability of the prospective designs.

  19. ShowFlow: A practical interface for groundwater modeling

    SciTech Connect (OSTI)

    Tauxe, J.D.

    1990-12-01T23:59:59.000Z

    ShowFlow was created to provide a user-friendly, intuitive environment for researchers and students who use computer modeling software. What traditionally has been a workplace available only to those familiar with command-line based computer systems is now within reach of almost anyone interested in the subject of modeling. In the case of this edition of ShowFlow, the user can easily experiment with simulations using the steady state gaussian plume groundwater pollutant transport model SSGPLUME, though ShowFlow can be rewritten to provide a similar interface for any computer model. Included in this thesis is all the source code for both the ShowFlow application for Microsoft{reg sign} Windows{trademark} and the SSGPLUME model, a User's Guide, and a Developer's Guide for converting ShowFlow to run other model programs. 18 refs., 13 figs.

  20. Turbulence suppression in channel flows by small amplitude transverse wall oscillations

    E-Print Network [OSTI]

    Jovanovic, Mihailo

    and experimental investigations in channel,2­4 pipe,5­7 and boundary layer8­11 flows. In this paper, we model oscillatory wall motion or an oscillatory spanwise body force showed that a substantial drag reduction up

  1. Role of chaos in quantum communication through a dynamical dephasing channel

    SciTech Connect (OSTI)

    Barreto Lemos, Gabriela [Instituto de Fisica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, Rio de Janeiro, RJ 21941-972, RJ (Brazil); Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria, Via Valleggio 11, I-22100 Como (Italy); Benenti, Giuliano [CNISM, CNR-INFM and Center for Nonlinear and Complex Systems, Universita degli Studi dell'Insubria, Via Valleggio 11, I-22100 Como (Italy); Istituto Nazionale di Fisica Nucleare, Sezione di Milano, via Celoria 16, I-20133 Milano (Italy)

    2010-06-15T23:59:59.000Z

    In this article we treat the subject of chaotic environments with few degrees of freedom in quantum communication by investigating a conservative dynamical map as a model of a dephasing quantum channel. When the channel's dynamics is chaotic, we investigate the model's semi-classical limit and show that the entropy exchange grows at a constant rate which depends on a single parameter (the interaction strength), analogous to stochastic models of dephasing channels. We analyze memory effects in the channel and present strong physical arguments to support that the present model is forgetful in the chaotic regime while memory effects in general cannot be ignored when channel dynamics is regular. In order to render the nonchaotic channel forgetful, it becomes necessary to apply a reset to the channel and this reset can efficiently be modeled by application of a chaotic map. We may then refer to encoding theorems (valid in the case of forgetful channels) to present evidence of a transition from noiseless to noisy channel due to the environment's transition from regular to chaotic dynamics.

  2. Multiple channel data acquisition system

    DOE Patents [OSTI]

    Crawley, H. Bert (Ames, IA); Rosenberg, Eli I. (Ames, IA); Meyer, W. Thomas (Ames, IA); Gorbics, Mark S. (Ames, IA); Thomas, William D. (Boone, IA); McKay, Roy L. (Ames, IA); Homer, Jr., John F. (Ames, IA)

    1990-05-22T23:59:59.000Z

    A multiple channel data acquisition system for the transfer of large amounts of data from a multiplicity of data channels has a plurality of modules which operate in parallel to convert analog signals to digital data and transfer that data to a communications host via a FASTBUS. Each module has a plurality of submodules which include a front end buffer (FEB) connected to input circuitry having an analog to digital converter with cache memory for each of a plurality of channels. The submodules are interfaced with the FASTBUS via a FASTBUS coupler which controls a module bus and a module memory. The system is triggered to effect rapid parallel data samplings which are stored to the cache memories. The cache memories are uploaded to the FEBs during which zero suppression occurs. The data in the FEBs is reformatted and compressed by a local processor during transfer to the module memory. The FASTBUS coupler is used by the communications host to upload the compressed and formatted data from the module memory. The local processor executes programs which are downloaded to the module memory through the FASTBUS coupler.

  3. Multiple channel data acquisition system

    DOE Patents [OSTI]

    Crawley, H.B.; Rosenberg, E.I.; Meyer, W.T.; Gorbics, M.S.; Thomas, W.D.; McKay, R.L.; Homer, J.F. Jr.

    1990-05-22T23:59:59.000Z

    A multiple channel data acquisition system for the transfer of large amounts of data from a multiplicity of data channels has a plurality of modules which operate in parallel to convert analog signals to digital data and transfer that data to a communications host via a FASTBUS. Each module has a plurality of submodules which include a front end buffer (FEB) connected to input circuitry having an analog to digital converter with cache memory for each of a plurality of channels. The submodules are interfaced with the FASTBUS via a FASTBUS coupler which controls a module bus and a module memory. The system is triggered to effect rapid parallel data samplings which are stored to the cache memories. The cache memories are uploaded to the FEBs during which zero suppression occurs. The data in the FEBs is reformatted and compressed by a local processor during transfer to the module memory. The FASTBUS coupler is used by the communications host to upload the compressed and formatted data from the module memory. The local processor executes programs which are downloaded to the module memory through the FASTBUS coupler. 25 figs.

  4. Continuous-variable private quantum channel

    SciTech Connect (OSTI)

    Bradler, Kamil [Instituto de Fisica, UNAM, Apdo. Postal 20-364, Mexico DF 01000 (Mexico); Department of Optics, Palacky University, 17. listopadu 50, 77200 Olomouc (Czech Republic)

    2005-10-15T23:59:59.000Z

    In this paper we introduce the concept of quantum private channel within the continuous variables framework (CVPQC) and investigate its properties. In terms of CVPQC we naturally define a 'maximally' mixed state in phase space together with its explicit construction and show that for increasing number of encryption operations (which sets the length of a shared key between Alice and Bob) the encrypted state is arbitrarily close to the maximally mixed state in the sense of the Hilbert-Schmidt distance. We bring the exact solution for the distance dependence and give also a rough estimate of the necessary number of bits of the shared secret key (i.e., how much classical resources are needed for an approximate encryption of a generally unknown continuous-variable state). The definition of the CVPQC is analyzed from the Holevo bound point of view which determines an upper bound of information about an incoming state an eavesdropper is able to get from his optimal measurement.

  5. Considering removing "Show Preview" button on utility rate form...

    Open Energy Info (EERE)

    Rmckeel's picture Submitted by Rmckeel(297) Contributor 22 April, 2013 - 13:55 Utility Rates I'm considering removing the "Show Preview" button, since it does not work (javascript...

  6. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

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

    Dynein Motor Domain Shows Ring-Shaped Motor, Buttress Print Movement is fundamental to life. It takes place even at the cellular level where cargo is continually being transported...

  7. acid show improved: Topics by E-print Network

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

    Marton 2001-01-01 8 ATOC 3500CHEM 3151 Problem 11, Spring 2014 We Didn't Get Much into Acid Rain...this shows how rainwater is naturally Geosciences Websites Summary: ATOC 3500...

  8. Biological Monitoring at Amchitka Appears to Show Impacts from...

    Energy Savers [EERE]

    of the monitoring showed that Dolly Varden (a type of freshwater char, a trout-like fish), rockweed (littoral-zone algae), and to a lesser extent, Irish Lord (a small...

  9. Conference shows high school girls their scientific future |...

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

    Division, speaks with event attendees. Click to enlarge. Conference shows high school girls their scientific future By Justin H.S. Breaux * April 7, 2014 Tweet EmailPrint...

  10. Secretary Chu Speaks at the 2010 Washington Auto Show

    Broader source: Energy.gov [DOE]

    at the 2010 Washington Auto Show, Secretary Chu lays out a roadmap for how the U.S. can lead the world in making the clean vehicles we need. He also announced that the Department of Energy had...

  11. New Report Shows Trend Toward Larger Offshore Wind Systems, with...

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

    Energy Department today released a new report showing progress for the U.S. offshore wind energy market in 2012, including the completion of two commercial lease auctions for...

  12. Use of Preventative and Therapeutic Drugs in Show Market Animals

    E-Print Network [OSTI]

    Faries Jr., Floron C.

    2001-03-12T23:59:59.000Z

    Various medicines are used in show market livestock and poultry, but exhibitors must ensure that the carcasses do not contain illegal residues of drugs, chemicals and feed additives. Only approved substances should be used. Illegal uses of drugs...

  13. Global Climate Change Assessment Report Shows Nations Not Doing...

    Open Energy Info (EERE)

    Global Climate Change Assessment Report Shows Nations Not Doing Enough Home > Blogs > Dc's blog Dc's picture Submitted by Dc(107) Contributor 5 November, 2014 - 14:49 The latest...

  14. Performance Limitations of Linear Systems over Additive White Noise Channels

    E-Print Network [OSTI]

    Li, Yiqian

    2011-01-01T23:59:59.000Z

    Control over additive white noise channels . . . . . . . 1.3Additive white noise channel . . . . . . . . . . . . . . Angaussian systems over additive gaussian wireles fading

  15. Joint source channel coding for non-ergodic channels: the distortion signal-to-noise ratio (SNR) exponent perspective

    E-Print Network [OSTI]

    Bhattad, Kapil

    2008-10-10T23:59:59.000Z

    . . . . . . . . . . . . . . . . . . . . . . . 72 F. Performance Analysis . . . . . . . . . . . . . . . . . . . . . 73 1. SISO / SIMO / MISO . . . . . . . . . . . . . . . . . . 77 2. The General MIMO Channel . . . . . . . . . . . . . . 79 3. Block Fading SISO Channel / Parallel SISO Channels 86 4... the mutual information between U and V. The second part, channel coding, is to send the bit stream B reliably over the channel. This is possible if and only if the channel coding rate Rc (bits per channel use) is less than the capacity of the channel...

  16. Surface plasmon resonance shows that type IV pili are

    E-Print Network [OSTI]

    Buckling, Angus

    REPORT Surface plasmon resonance shows that type IV pili are important in surface attachment. Here, using the surface analytical technique, surface plasmon resonance (SPR), we follow the attachment; pili; surface plasmon resonance; biofilm formation 1. INTRODUCTION Bacterial attachment is a critical

  17. Oil and gas shows in the Salina basin

    SciTech Connect (OSTI)

    Newell, K.D.; Lambert, M.; Berendsen, P.

    1989-01-01T23:59:59.000Z

    This book presents data from drillers' records and other information on the Salina basin wells in north-central Kansas. A listing that includes well name, operator, location, completion date, depth intervals, and formation name for each well is included. A map showing oil and gas fields in the surrounding area and wells drilled within the basin is offered.

  18. Fig. 1. Schematic of LDX device showing three superconducting

    E-Print Network [OSTI]

    1 Fig. 1. Schematic of LDX device showing three superconducting magnets and the plasma@psfc.mit.edu Abstract: We report the first production of high beta plasma confined by a laboratory superconducting-field superconducting dipole magnet, termed the "floating coil" was supported by three thin support rods. In this mode

  19. Joint Power and Resource Allocation for Block-Fading Relay-Assisted Broadcast Channels

    E-Print Network [OSTI]

    Shaqfeh, Mohammad

    2012-01-01T23:59:59.000Z

    We provide the solution for optimizing the power and resource allocation over block-fading relay-assisted broadcast channels in order to maximize the long term average achievable rates region of the users. The problem formulation assumes regenerative (repetition coding) decode-and-forward (DF) relaying strategy, long-term average total transmitted power constraint, orthogonal multiplexing of the users messages within the channel blocks, possibility to use a direct transmission (DT) mode from the base station to the user terminal directly or a relaying (DF) transmission mode, and partial channel state information. We show that our optimization problem can be transformed into an equivalent "no-relaying" broadcast channel optimization problem with each actual user substituted by two virtual users having different channel qualities and multiplexing weights. The proposed power and resource allocation strategies are expressed in closed-form that can be applied practically in centralized relay-assisted wireless netw...

  20. The private classical capacity with a symmetric side channel and its application to quantum cryptography

    E-Print Network [OSTI]

    Graeme Smith

    2007-05-25T23:59:59.000Z

    We study the symmetric-side-channel-assisted private capacity of a quantum channel, for which we provide a single-letter formula. This capacity is additive, convex, and, for degradable channels, equal to the unassisted private capacity. While a channel's (unassisted) capacity for for private classical communication may be strictly larger than its quantum capacity, we will show that these capacities are equal for degradable channels, thus demonstrating the equivalence of privacy and quantum coherence in this context. We use these ideas to find new bounds on the key rate of quantum key distribution protocols with one-way classical post-processing. For the Bennett-Brassard-84 (BB84) protocol, our results demonstrate that collective attacks are strictly stronger than individual attacks.

  1. Magnetohydrodynamic (MHD) channel corner seal

    DOE Patents [OSTI]

    Spurrier, Francis R. (Pittsburgh, PA)

    1980-01-01T23:59:59.000Z

    A corner seal for an MHD duct includes a compressible portion which contacts the duct walls and an insulating portion which contacts the electrodes, sidewall bars and insulators. The compressible portion may be a pneumatic or hydraulic gasket or an open-cell foam rubber. The insulating portion is segmented into a plurality of pieces of the same thickness as the electrodes, insulators and sidewall bars and aligned therewith, the pieces aligned with the insulator being of a different size from the pieces aligned with the electrodes and sidewall bars to create a stepped configuration along the corners of the MHD channel.

  2. Strong converse exponents for a quantum channel discrimination problem and quantum-feedback-assisted communication

    E-Print Network [OSTI]

    Tom Cooney; Milán Mosonyi; Mark M. Wilde

    2015-02-26T23:59:59.000Z

    This paper studies the difficulty of discriminating between an arbitrary quantum channel and a "replacer" channel that discards its input and replaces it with a fixed state. The results obtained here generalize those known in the theory of quantum hypothesis testing for binary state discrimination. We show that, in this particular setting, the most general adaptive discrimination strategies provide no asymptotic advantage over non-adaptive tensor-power strategies. This conclusion follows by proving a quantum Stein's lemma for this channel discrimination setting, showing that a constant bound on the Type I error leads to the Type II error decreasing to zero exponentially quickly at a rate determined by the maximum relative entropy registered between the channels. The strong converse part of the lemma states that any attempt to make the Type II error decay to zero at a rate faster than the channel relative entropy implies that the Type I error necessarily converges to one. We then refine this latter result by identifying the optimal strong converse exponent for this task. As a consequence of these results, we can establish a strong converse theorem for the quantum-feedback-assisted capacity of a channel, sharpening a result due to Bowen. Furthermore, our channel discrimination result demonstrates the asymptotic optimality of a non-adaptive tensor-power strategy in the setting of quantum illumination, as was used in prior work on the topic. The sandwiched Renyi relative entropy is a key tool in our analysis. Finally, by combining our results with recent results of Hayashi and Tomamichel, we find a novel operational of the mutual information of a quantum channel N as the optimal type II error exponent when discriminating between a large number of independent instances of N and an arbitrary "worst-case" replacer channel chosen from the set of all replacer channels.

  3. Secretary Chu Speaks at the 2010 Washington Auto Show

    SciTech Connect (OSTI)

    Secretary Chu

    2010-02-03T23:59:59.000Z

    Secretary Chu lays out a roadmap for how the U.S. can lead the world in making the clean vehicles we need at the 2010 Washington Auto Show. He also announced that the Department of Energy had closed on a $1.4 billion loan to Nissan to build the all-electric LEAF in Tennessee and create up to 1,300 American jobs.

  4. Several engine technology advances show potential in labs; Part 2

    SciTech Connect (OSTI)

    McCoy, J.J. (Tenneco Gas Co., Houston, TX (United States)); Willson, B. (Colorado State Univ., Fort Collins, CO (United States). Engines and Energy Conservation Lab.)

    1994-07-01T23:59:59.000Z

    Cutting fuel consumption and reducing emissions are dominant goals of stationary gas engine operators. Recent technology advances show promise and could result in money-saving retrofit options. Selected new technologies include sensors, actuators--defined as anything controlling the engine: fuel and ignition--and control techniques. An attractive feature of most of these technologies is that they can be retrofitting onto existing engines, allowing the potential for improved performance at a fraction of engine replacement cost. This paper describes these technologies.

  5. Secretary Chu Speaks at the 2010 Washington Auto Show

    ScienceCinema (OSTI)

    Secretary Chu

    2010-09-01T23:59:59.000Z

    Secretary Chu lays out a roadmap for how the U.S. can lead the world in making the clean vehicles we need at the 2010 Washington Auto Show. He also announced that the Department of Energy had closed on a $1.4 billion loan to Nissan to build the all-electric LEAF in Tennessee and create up to 1,300 American jobs.

  6. FIVE KEPLER TARGET STARS THAT SHOW MULTIPLE TRANSITING EXOPLANET CANDIDATES

    SciTech Connect (OSTI)

    Steffen, Jason H. [Fermilab Center for Particle Astrophysics, P.O. Box 500, Batavia, IL 60510 (United States); Batalha, Natalie M. [Department of Astronomy and Physics, San Jose State University, San Jose, CA 95192 (United States); Borucki, William J.; Caldwell, Douglas A.; Haas, Michael J.; Jenkins, Jon M.; Koch, David; Lissauer, Jack J. [NASA Ames Research Center, Moffett Field, CA 94035 (United States); Buchhave, Lars A.; Fabrycky, Daniel C.; Fressin, Francois; Holman, Matthew J.; Latham, David W. [Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, MA 02138 (United States); Cochran, William D.; Endl, Michael [McDonald Observatory, University of Texas, Austin, TX 78712-2059 (United States); Ford, Eric B.; Moorhead, Althea V. [Department of Astronomy, University of Florida, 211 Bryant Space Science Center, Gainesville, FL 32611-2055 (United States); Fortney, Jonathan J. [Department of Astronomy and Astrophysics, University of California, Santa Cruz, CA 95064 (United States); Howell, Steve B. [National Optical Astronomy Observatory, Tucson, AZ 85719 (United States); Isaacson, Howard [Astronomy Department, University of California Berkeley, Berkeley, CA 9472 (United States)

    2010-12-10T23:59:59.000Z

    We present and discuss five candidate exoplanetary systems identified with the Kepler spacecraft. These five systems show transits from multiple exoplanet candidates. Should these objects prove to be planetary in nature, then these five systems open new opportunities for the field of exoplanets and provide new insights into the formation and dynamical evolution of planetary systems. We discuss the methods used to identify multiple transiting objects from the Kepler photometry as well as the false-positive rejection methods that have been applied to these data. One system shows transits from three distinct objects while the remaining four systems show transits from two objects. Three systems have planet candidates that are near mean motion commensurabilities-two near 2:1 and one just outside 5:2. We discuss the implications that multi-transiting systems have on the distribution of orbital inclinations in planetary systems, and hence their dynamical histories, as well as their likely masses and chemical compositions. A Monte Carlo study indicates that, with additional data, most of these systems should exhibit detectable transit timing variations (TTVs) due to gravitational interactions, though none are apparent in these data. We also discuss new challenges that arise in TTV analyses due to the presence of more than two planets in a system.

  7. Morphology of rain water channelization in systematically varied model sandy soils

    E-Print Network [OSTI]

    Y. Wei; C. M. Cejas; R. Barrois; R. Dreyfus; D. J. Durian

    2014-03-13T23:59:59.000Z

    We visualize the formation of fingered flow in dry model sandy soils under different raining conditions using a quasi-2d experimental set-up, and systematically determine the impact of soil grain diameter and surface wetting property on water channelization phenomenon. The model sandy soils we use are random closely-packed glass beads with varied diameters and surface treatments. For hydrophilic sandy soils, our experiments show that rain water infiltrates into a shallow top layer of soil and creates a horizontal water wetting front that grows downward homogeneously until instabilities occur to form fingered flows. For hydrophobic sandy soils, in contrast, we observe that rain water ponds on the top of soil surface until the hydraulic pressure is strong enough to overcome the capillary repellency of soil and create narrow water channels that penetrate the soil packing. Varying the raindrop impinging speed has little influence on water channel formation. However, varying the rain rate causes significant changes in water infiltration depth, water channel width, and water channel separation. At a fixed raining condition, we combine the effects of grain diameter and surface hydrophobicity into a single parameter and determine its influence on water infiltration depth, water channel width, and water channel separation. We also demonstrate the efficiency of several soil water improvement methods that relate to rain water channelization phenomenon, including pre-wetting sandy soils at different level before rainfall, modifying soil surface flatness, and applying superabsorbent hydrogel particles as soil modifiers.

  8. Transfer information remotely via noise entangled coherent channels

    E-Print Network [OSTI]

    A. El Allati; N. Metwally; Y. Hassouni

    2010-02-11T23:59:59.000Z

    In this contribution, a generalized protocol of quantum teleportation is suggested to investigate the possibility of remotely transfer unknown multiparities entangled coherent state. A theoretical technique is introduced to generate maximum entangled coherent states which are used as quantum channels. We show that the mean photon number plays a central role on the fidelity of the transferred information. The noise parameter can be considered as a control parameter only for small values of the mean photon number.

  9. Debugging and teaching tools show, e.g., stimulus waveform and

    E-Print Network [OSTI]

    stimulation via RIB2 Sentence intelligibility measurement · Custom measurement procedure `Matrix-channel background babble noise using SoundMexPro · Extern hardware interface is used to communicate

  10. Modified Yeast Show Improved Xylose Fermentation and Toxin Tolerance -

    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 PowerCherries 82981-1cnHighandSWPA / SPRA /Ml'. WilliamEnergy Innovation Portal Show Improved

  11. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

    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 AdministrationField Campaign:INEA :Work with Jefferson LabDynein Motor Domain Shows

  12. Dynein Motor Domain Shows Ring-Shaped Motor, Buttress

    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 AdministrationField Campaign:INEA :Work with Jefferson LabDynein Motor Domain ShowsDynein

  13. Private Interactive Communication Across an Adversarial Channel

    E-Print Network [OSTI]

    Private Interactive Communication Across an Adversarial Channel Ran Gelles, Amit Sahai, and Akshay Wadia Department of Computer Science, University of California, Los Angeles, CA, USA {gelles, sahai

  14. Southern California Channel Islands Bibliography, through 1992

    E-Print Network [OSTI]

    Channel Islands National Marine Sanctuary

    1992-01-01T23:59:59.000Z

    Channel/Santa Maria Basin/Elk Hills/San Joaquin Basin/Chicosiliceous composition/Elk Hills/San Joaquin Basin/Chico

  15. Southern California Channel Islands Bibliography, through 1992

    E-Print Network [OSTI]

    Channel Islands National Marine Sanctuary

    1992-01-01T23:59:59.000Z

    evaluation/offshore/Santa Maria/ Santa Barbara/Santa Maria Basin/Santa Barbara Channel/Los Angeles Basin/economic geology/energy sources/petroleum. #

  16. Anisotropic flow in striped superhydrophobic channels

    E-Print Network [OSTI]

    Zhou, Jiajia; Schmid, Friederike; Vinogradova, Olga I

    2012-01-01T23:59:59.000Z

    We report results of dissipative particle dynamics simulations and develop a semi-analytical theory and of an anisotropic flow in a parallel-plate channel with two superhydrophobic striped walls. Our approach is valid for any local slip at the gas sectors and an arbitrary distance between the plates, ranging from a thick to a thin channel. It allows us to optimize area fractions, slip lengths, channel thickness and texture orientation to maximize a transverse flow. Our results may be useful for extracting effective slip tensors from global measurements, such as the permeability of a channel, in experiments or simulations, and may also find applications in passive microfluidic mixing.

  17. Anisotropic flow in striped superhydrophobic channels

    E-Print Network [OSTI]

    Jiajia Zhou; Aleksey V. Belyaev; Friederike Schmid; Olga I. Vinogradova

    2012-05-02T23:59:59.000Z

    We report results of dissipative particle dynamics simulations and develop a semi-analytical theory of an anisotropic flow in a parallel-plate channel with two superhydrophobic striped walls. Our approach is valid for any local slip at the gas sectors and an arbitrary distance between the plates, ranging from a thick to a thin channel. It allows us to optimize area fractions, slip lengths, channel thickness and texture orientation to maximize a transverse flow. Our results may be useful for extracting effective slip tensors from global measurements, such as the permeability of a channel, in experiments or simulations, and may also find applications in passive microfluidic mixing.

  18. Combined source-channel coding for a power and bandwidth constrained noisy channel

    E-Print Network [OSTI]

    Raja, Nouman Saeed

    2005-02-17T23:59:59.000Z

    This thesis proposes a framework for combined source-channel coding under power and bandwidth constrained noisy channel. The framework is then applied to progressive image coding transmission using constant envelope M-ary Phase Shift Key (MPSK...

  19. Statistical Hot Channel Analysis for the NBSR

    SciTech Connect (OSTI)

    Cuadra A.; Baek J.

    2014-05-27T23:59:59.000Z

    A statistical analysis of thermal limits has been carried out for the research reactor (NBSR) at the National Institute of Standards and Technology (NIST). The objective of this analysis was to update the uncertainties of the hot channel factors with respect to previous analysis for both high-enriched uranium (HEU) and low-enriched uranium (LEU) fuels. Although uncertainties in key parameters which enter into the analysis are not yet known for the LEU core, the current analysis uses reasonable approximations instead of conservative estimates based on HEU values. Cumulative distribution functions (CDFs) were obtained for critical heat flux ratio (CHFR), and onset of flow instability ratio (OFIR). As was done previously, the Sudo-Kaminaga correlation was used for CHF and the Saha-Zuber correlation was used for OFI. Results were obtained for probability levels of 90%, 95%, and 99.9%. As an example of the analysis, the results for both the existing reactor with HEU fuel and the LEU core show that CHFR would have to be above 1.39 to assure with 95% probability that there is no CHF. For the OFIR, the results show that the ratio should be above 1.40 to assure with a 95% probability that OFI is not reached.

  20. Additivity and multiplicativity properties of some Gaussian channels for Gaussian inputs

    E-Print Network [OSTI]

    Tohya Hiroshima

    2006-02-13T23:59:59.000Z

    We prove multiplicativity of maximal output $p$ norm of classical noise channels and thermal noise channels of arbitrary modes for all $p>1$ under the assumption that the input signal states are Gaussian states. As a direct consequence, we also show the additivity of the minimal output entropy and that of the energy-constrained Holevo capacity for those Gaussian channels under Gaussian inputs. To the best of our knowledge, newly discovered majorization relation on symplectic eigenvalues, which is also of independent interest, plays a central role in the proof.

  1. 2005 International Conference on Wireless Networks, Communications and Mobile Computing Optimal Power Control for Multiple Access Channel

    E-Print Network [OSTI]

    Chen, Rong-Rong

    Power Control for Multiple Access Channel with Peak and Average Power Constraints Rong-Rong Chen}I@ece.utah.edu Abstract- In this paper, we study optimal power control for multiple access channel with peak and average and the receiver. We characterize the structures of the optimal power control policy and show that the optimal

  2. Joint channel estimation and decoding of root LDPC codes in block-fading channels

    E-Print Network [OSTI]

    Andriyanova, Iryna

    Joint channel estimation and decoding of root LDPC codes in block-fading channels Iryna Andriyanova receivers for joint decoding and channel-state estimation for transmission on block-fading chan- nels of root-LDPC-coded signals. Root-LDPC codes are known to be most performant codes for block

  3. Security bound of continuous-variable quantum key distribution with noisy coherent states and channel

    E-Print Network [OSTI]

    Yong Shen; Jian Yang; Hong Guo

    2009-06-29T23:59:59.000Z

    Security of a continuous-variable quantum key distribution protocol based on noisy coherent states and channel is analyzed. Assuming the noise of coherent states is induced by Fred, a neutral party relative to others, we prove that the prepare and measurement scheme and entanglement-based scheme are equivalent. Then, we show that this protocol is secure against Gaussian collective attacks even if the channel is lossy and noisy, and further, a lower bound to the secure key rate is derived.

  4. RESULTS & CONCLUSION The analysis (above) shows that there are multiple reaches of Trout Brook and Smith

    E-Print Network [OSTI]

    Barclay, David J.

    and April 1995 and 2006 were downloaded from the NYS Geographic Information Systems Clearinghouse. The 1995 Stream channel migration is a significant problem that can cause damage to roads, buildings and other potentially cheaper and less invasive options, such as not building in areas where channels are migrating

  5. Distributed Interference Pricing with MISO Channels

    E-Print Network [OSTI]

    Kuzmanovic, Aleksandar

    Distributed Interference Pricing with MISO Channels Changxin Shi, Randall A. Berry, and Michael L an interference channel consisting of multi- input, single-output (MISO) wireless links. The objective generalized to a MISO network, as shown in Sec- tion II. Such an algorithm was previously presented in [3

  6. Optimization of Energy Harvesting MISO Communication Channels

    E-Print Network [OSTI]

    Gesbert, David

    1 Optimization of Energy Harvesting MISO Communication Channels Rajeev Gangula, Student Member-to-point multiple-input single-output (MISO) communication system is con- sidered when both the transmitter (TX bound on the ergodic rate of MISO channel with beamforming and limited feedback. Feedback bit allocation

  7. Energy Harvesting Diamond Channel with Energy Cooperation

    E-Print Network [OSTI]

    Ulukus, Sennur

    Energy Harvesting Diamond Channel with Energy Cooperation Berk Gurakan Sennur Ulukus Department@umd.edu Abstract--We consider the energy harvesting diamond channel, where the source and two relays harvest energy the option of wirelessly transferring some of its energy to the relays via energy cooperation. We find

  8. Fourier transform channeled spectropolarimetry in the MWIR

    E-Print Network [OSTI]

    Dereniak, Eustace L.

    Fourier transform channeled spectropolarimetry in the MWIR Michael W. Kudenov,1 Nathan A. Hagen, 1 Abstract: A complete Fourier Transform Spectropolarimeter in the MWIR is demonstrated. The channeled and links 1. P. Griffiths and J. D. Haseth, "Fourier Transform Infrared Spectrometry," (John Wiley & Sons

  9. Constrained capacity of MIMO Rayleigh fading channels

    E-Print Network [OSTI]

    He, Wenyan

    2011-08-08T23:59:59.000Z

    In this thesis channel capacity of a special type of multiple-input multiple-output (MIMO) Rayleigh fading channels is studied, where the transmitters are subject to a finite phase-shift keying (PSK) input alphabet. The constraint on the input...

  10. General teleportation channel, singlet fraction and quasi-distillation

    E-Print Network [OSTI]

    Pawel Horodecki; Michal Horodecki; Ryszard Horodecki

    1999-03-02T23:59:59.000Z

    We prove a theorem on direct relation between the optimal fidelity $f_{max}$ of teleportation and the maximal singlet fraction $F_{max}$ attainable by means of trace-preserving LQCC action (local quantum and classical communication). For a given bipartite state acting on $C^d\\otimes C^d$ we have $f_{max}= {F_{max}d+1\\over d+1}$. We assume completely general teleportation scheme (trace preserving LQCC action over the pair and the third particle in unknown state). The proof involves the isomorphism between quantum channels and a class of bipartite states. We also exploit the technique of $U\\otimes U^*$ twirling states (random application of unitary transformation of the above form) and the introduced analogous twirling of channels. We illustrate the power of the theorem by showing that {\\it any} bound entangled state does not provide better fidelity of teleportation than for the purely classical channel. Subsequently, we apply our tools to the problem of the so-called conclusive teleportation, then reduced to the question of optimal conclusive increasing of singlet fraction. We provide an example of state for which Alice and Bob have no chance to obtain perfect singlet by LQCC action, but still singlet fraction arbitrarily close to unity can be obtained with nonzero probability. We show that a slight modification of the state has a threshold for singlet fraction which cannot be exceeded anymore.

  11. Separation of chiral particles in micro- or nanofluidic channels

    E-Print Network [OSTI]

    Sebastian Meinhardt; Jens Smiatek; Ralf Eichhorn; Friederike Schmid

    2012-04-18T23:59:59.000Z

    We propose a method to separate enantiomers in microfluidic or nanofluidic channels. It requires flow profiles which break chiral symmetry and have regions with high local shear. Such profiles can be generated in channels confined by walls with different hydrodynamic boundary conditions (e.g. slip lengths). Due to a nonlinear hydrodynamic effect, particles with different chirality migrate at different speed and can be separated. The mechanism is demonstrated by computer simulations. We investigate the influence of thermal fluctuations (i.e. the P\\'eclet number) and show that the effect disappears in the linear response regime. The details of the microscopic flow are important and determine which volume forces are necessary to achieve separation.

  12. Separation of chiral particles in micro- or nanofluidic channels

    E-Print Network [OSTI]

    Meinhardt, Sebastian; Eichhorn, Ralf; Schmid, Friederike

    2012-01-01T23:59:59.000Z

    We propose a method to separate enantiomers in microfluidic or nanofluidic channels. It requires flow profiles which break chiral symmetry and have regions with high local shear. Such profiles can be generated in channels confined by walls with different hydrodynamic boundary conditions (e.g. slip lengths). Due to a nonlinear hydrodynamic effect, particles with different chirality migrate at different speed and can be separated. The mechanism is demonstrated by computer simulations. We investigate the influence of thermal fluctuations (i.e. the P\\'eclet number) and show that the effect disappears in the linear response regime. The details of the microscopic flow are important and determine which volume forces are necessary to achieve separation.

  13. Tidal channel deposits in Upper Cretaceous of northern Kaiparowits Plateau, Utah

    SciTech Connect (OSTI)

    Sanchez, J.D.; McCabe, P.J.

    1988-02-01T23:59:59.000Z

    Seven coarsening-upward sequences have been recognized in the 300 to 400-m thick John Henry Member of the Straight Cliffs Formation. These sequences have abundant hummocky cross-stratification and are interpreted as having formed by the progradation of wave-dominated shorelines. A detailed study of these sequences showed that in many cases channel deposits are incised into upper shoreface deposits. These channels are up t 15 m deep. Mudclasts, Ostrea and Inoceramus fragments, and pebbles are present at the base of many channels. Some channel lag deposits also contain logs with Teredolites borings. Thin units of flaser, wavy and lenticular bedding may be present at any position within the channel deposits but are most common higher in the sequences. The channels are, however, infilled predominantly with trough cross-bedded, fine to medium-grained sandstones. Some cross-beds show multiple reactivation surfaces and the bimodal nature of the paleocurrents suggests that the cross-beds were deposited by tidal currents. The presence of tidal bundles with double mud drapes in a few cross-beds confirms the interpretation of the sandstones as tidal channel deposits. At least 22 tidal bundles are present in one tidal bundle sequence, suggesting a semi-diurnal tidal cycle. Although, there is convincing evidence of tides within the channel deposits, the shoreface deposits show little evidence of reworking by tidal currents. Possible beach or intertidal mudflat deposits have a maximum thickness of 1.5 m. The Kaiparowits region during the Upper Cretaceous probably experienced, therefore, a microtidal regime with significant tidal currents being restricted to tidal inlets or estuaries.

  14. Tidal channel deposits in Upper Cretaceous of northern Kaiparowits Plateau, Utah

    SciTech Connect (OSTI)

    Sanchez, J.D.; McCabe, P.J.

    1988-01-01T23:59:59.000Z

    Seven coarsening-upward sequences have been recognized in the 300 to 400-m thick John Henry Member of the Straight Cliffs Formation. These sequences have abundant hummocky cross-stratification and are interpreted as having formed by the progradation of wave-dominated shorelines. A detailed study of these sequences showed that in many cases channel deposits are incised into upper shoreface deposits. These channels are up to 15 m deep. Mudclasts, Ostrea and Inoceramus fragments, and pebbles are present at the base of many channels. Some channel lag deposits also contain logs with Teredolites borings. Thin units of flaser, wavy and lenticular bedding may be present at any position within the channel deposits but are most common higher in the sequences. The channels are, however, infilled predominantly with trough cross-bedded, fine to medium-grained sandstones. Some crossbeds show multiple reactivation surfaces and the bimodal nature of the paleocurrents suggests that the cross-beds were deposited by tidal currents. The presence of tidal bundles with double mud drapes in a few cross-beds confirms the interpretation of the sandstones as tidal channel deposits. At least 22 tidal bundles are present in one tidal bundle sequence, suggesting a semi-diurnal tidal cycle. Although there is convincing evidence of tides within the channel deposits, the shoreface deposits show little evidence of reworking by tidal currents. Possible beach or intertidal mudflat deposits have a maximum thickness of 1.5 m. The Kaiparowits region during the Upper Cretaceous probably experience, therefore, a microtidal regime with significant tidal currents being restricted to tidal inlets or estuaries.

  15. Measurement of heat transfer and pressure drop in rectangular channels with turbulence promoters. Final report

    SciTech Connect (OSTI)

    Han, J. C.; Park, J. S.; Ibrahim, M. Y.

    1986-09-01T23:59:59.000Z

    Periodic rib turbulators were used in advanced turbine cooling designs to enhance the internal heat transfer. The objective of the present project was to investigate the combined effects of the rib angle of attack and the channel aspect ratio on the local heat transfer and pressure drop in rectangular channels with two opposite ribbed walls for Reynolds number varied from 10,000 to 60,000. The channel aspect ratio (W/H) was varied from 1 to 2 to 4. The rib angle of attack (alpha) was varied from 90 to 60 to 45 to 30 degree. The highly detailed heat transfer coefficient distribution on both the smooth side and the ribbed side walls from the channel sharp entrance to the downstream region were measured. The results showed that, in the square channel, the heat transfer for the slant ribs (alpha = 30 -45 deg) was about 30% higher that of the transverse ribs (alpha = 90 deg) for a constant pumping power. However, in the rectangular channels (W/H = 2 and 4, ribs on W side), the heat transfer at alpha = 30 -45 deg was only about 5% higher than 90 deg. The average heat transfer and friction correlations were developed to account for rib spacing, rib angle, and channel aspect ratio over the range of roughness Reynolds number.

  16. Hydraulic and slurry flows through a channel contraction

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    Hydraulic and slurry flows through a channel contraction Onno Bokhove o, Twente #12;Hydraulic flow through channel contraction Outline · 1. Introduction · 2. Experiments · 3. Conclusions · References ISSF 2008 University of Twente Page 2 #12;Hydraulic flow through channel contraction

  17. Maximum likelihood sequence estimation for multipath fading channels

    E-Print Network [OSTI]

    Pautler, Joseph James

    2000-01-01T23:59:59.000Z

    This thesis addresses receiver design for multipath fading channels. The channel model was chosen to closely resemble a typical land mobile fading channel. Three receivers will be compared in this work. The first will be the optimum receiver...

  18. Solution to time-energy costs of quantum channels

    E-Print Network [OSTI]

    Chi-Hang Fred Fung; H. F. Chau; Chi-Kwong Li; Nung-Sing Sze

    2014-12-16T23:59:59.000Z

    We derive a formula for the time-energy costs of general quantum channels proposed in [Phys. Rev. A 88, 012307 (2013)]. This formula allows us to numerically find the time-energy cost of any quantum channel using positive semidefinite programming. We also derive a lower bound to the time-energy cost for any channels and the exact the time-energy cost for a class of channels which includes the qudit depolarizing channels and projector channels as special cases.

  19. Steady-state estuarine modeling of the Brownsville ship channel

    E-Print Network [OSTI]

    Maldonado, Roberto Jaime

    1976-01-01T23:59:59.000Z

    Channel 17. Resultant Tidal Velocities Brownsville Ship Channel 18. Summary of Inflow Data Brownsvi lie Ship Channel Modelinp 14Z 145 149 LIST OF ILLUSTRATIONS Figure 1 Drowns vi 1 le Ship Channel and Contiguous Waters Sam pl i ng Stat i on Loca... ti ons San Martin Lake System . 3 Sampling Station Locations, Fishing Harbor Climatological Occurrence Physical Sampling Station Locations Brownsville Ship Channel 6 Salinity, Brownsville Ship Channel, May 1975 . 7 Temperature, Brownsville Ship...

  20. 6340 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 58, NO. 12, DECEMBER 2010 Binary Consensus Over Fading Channels

    E-Print Network [OSTI]

    Mostofi, Yasamin

    are with the Electrical and Computer Engineering Depart- ment, University of New Mexico, Albuquerque, NM 87131 USA (e in fading en- vironments. We show the impact of channel unreliability and net- work topology on consensus

  1. Analysis of Crystal Lattice Deformation by Ion Channeling. |...

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

    Crystal Lattice Deformation by Ion Channeling. Analysis of Crystal Lattice Deformation by Ion Channeling. Abstract: A model of dislocations has been developed for the use in Monte...

  2. Tidal channel and marshplain development : Cooley Landing salt pond restoration

    E-Print Network [OSTI]

    Garrity, Nick

    2003-01-01T23:59:59.000Z

    the rapidly eroding outboard mudflat channels. Introductionthis there is an extensive mudflat. PWA performed baselineerosion of the outboard mudflat channels. Since September

  3. Exploiting Heterogeneous Channel Coherence Intervals for Blind Interference Alignment

    E-Print Network [OSTI]

    Jafar, Syed Ali

    2011-01-01T23:59:59.000Z

    On the degrees of freedom of MISO broadcast channels withtrend, are listed below. 1. MISO BC with no CSIT for onemultiple input single output (MISO) broadcast channel (BC)

  4. Multi-channel polarized thermal emitter

    DOE Patents [OSTI]

    Lee, Jae-Hwang; Ho, Kai-Ming; Constant, Kristen P

    2013-07-16T23:59:59.000Z

    A multi-channel polarized thermal emitter (PTE) is presented. The multi-channel PTE can emit polarized thermal radiation without using a polarizer at normal emergence. The multi-channel PTE consists of two layers of metallic gratings on a monolithic and homogeneous metallic plate. It can be fabricated by a low-cost soft lithography technique called two-polymer microtransfer molding. The spectral positions of the mid-infrared (MIR) radiation peaks can be tuned by changing the periodicity of the gratings and the spectral separation between peaks are tuned by changing the mutual angle between the orientations of the two gratings.

  5. Complete Muon Cooling Channel Design and Simulations

    SciTech Connect (OSTI)

    Neuffer, D.V.; /Fermilab; Ankenbrandt, C.M.; Johnson, R.P.; Yoshikawa, C.Y.; /MUONS Inc., Batavia; Derbenev, Y.S.; Morozov, V.S.; /Jefferson Lab

    2012-05-01T23:59:59.000Z

    Considerable progress has been made in developing promising subsystems for muon beam cooling channels to provide the extraordinary reduction of emittances required for an energy-frontier muon collider. However, it has not yet been demonstrated that the various proposed cooling subsystems can be consolidated into an integrated end-to-end design. Presented here are concepts to address the matching of transverse emittances between subsystems through an extension of the theoretical framework of the Helical Cooling Channel (HCC), which allows a general analytical approach to guide the transition from one set of cooling channel parameters to another.

  6. Complete Muon Cooling Channel Design and Simulations

    SciTech Connect (OSTI)

    C. Y. Yoshikawa, C.M. Ankenbrandt, R.P. Johnson, Y.S. Derbenev, V.S. Morozov, D.V. Neuffer, K. Yonehara

    2012-07-01T23:59:59.000Z

    Considerable progress has been made in developing promising subsystems for muon beam cooling channels to provide the extraordinary reduction of emittances required for an energy-frontier muon collider. However, it has not yet been demonstrated that the various proposed cooling subsystems can be consolidated into an integrated end-to-end design. Presented here are concepts to address the matching of transverse emittances between subsystems through an extension of the theoretical framework of the Helical Cooling Channel (HCC), which allows a general analytical approach to guide the transition from one set of cooling channel parameters to another.

  7. Coupled-channel scattering on a torus

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

    Guo, Peng [JLAB; Dudek, Jozef Jon [Old Dominion U., JLAB; Edwards, Robert G. [JLAB; Szczepaniak, Adam Pawel [Indiana U.

    2013-07-01T23:59:59.000Z

    Based on the Hamiltonian formalism approach, a generalized Luscher's formula for two particle scattering in both the elastic and coupled-channel cases in moving frames is derived from a relativistic Lippmann-Schwinger equation. Some strategies for extracting scattering amplitudes for a coupled-channel system from the discrete finite-volume spectrum are discussed and illustrated with a toy model of two-channel resonant scattering. This formalism will, in the near future, be used to extract information about hadron scattering from lattice QCD computations.

  8. TWO-CHANNEL DIELECTRIC WAKE FIELD ACCELERATOR

    SciTech Connect (OSTI)

    Jay L. Hirshfield

    2012-05-30T23:59:59.000Z

    Experimental results are reported for test beam acceleration and deflection in a two-channel, cm-scale, rectangular dielectric-lined wakefield accelerator structure energized by a 14-MeV drive beam. The dominant waveguide mode of the structure is at {approx}30 GHz, and the structure is configured to exhibit a high transformer ratio ({approx}12:1). Accelerated bunches in the narrow secondary channel of the structure are continuously energized via Cherenkov radiation that is emitted by a drive bunch moving in the wider primary channel. Observed energy gains and losses, transverse deflections, and changes in the test bunch charge distribution compare favorably with predictions of theory.

  9. On complementary channels and the additivity problem

    E-Print Network [OSTI]

    A. S. Holevo

    2005-10-06T23:59:59.000Z

    We explore complementarity between output and environment of a quantum channel (or, more generally, CP map), making an observation that the output purity characteristics for complementary CP maps coincide. Hence, validity of the mutiplicativity/additivity conjecture for a class of CP maps implies its validity for complementary maps. The class of CP maps complementary to entanglement-breaking ones is described and is shown to contain diagonal CP maps as a proper subclass, resulting in new class of CP maps (channels) for which the multiplicativity/additivity holds. Covariant and Gaussian channels are discussed briefly in this context.

  10. Channels and jokers in continuous systems

    SciTech Connect (OSTI)

    Butkovskii, O. Ya., E-mail: olegb@vlsu.ru; Logunov, M. Yu. [Vladimir State University (Russian Federation)

    2007-06-15T23:59:59.000Z

    The Roessler system is used as an example to demonstrate that the reconstruction of a model nonlinear dynamical system from an observed time series reveals phase-space regions called channels and jokers [3]. The proposed method for finding such regions is shown to be robust to noise and inaccuracy (redundancy) of the models used in the reconstruction procedure. The evolution of local Lyapunov exponents of attractors is examined for the model systems, and its relation to channels and jokers is exposed. It is shown that channels and jokers can be used in predictive modeling. The quality of such models is analyzed by invoking the concept of degree of predictability.

  11. Modeling, Real-Time Estimation, and Identification of UWB Indoor Wireless Channels

    SciTech Connect (OSTI)

    Olama, Mohammed M [ORNL] [ORNL; Djouadi, Seddik M [ORNL] [ORNL; Li, Yanyan [ORNL] [ORNL; Fathy, Aly [University of Tennessee (UT)] [University of Tennessee (UT)

    2013-01-01T23:59:59.000Z

    In this paper, stochastic differential equations (SDEs) are used to model ultrawideband (UWB) indoor wireless channels. We show that the impulse responses for time-varying indoor wireless channels can be approximated in a mean square sense as close as desired by impulse responses that can be realized by SDEs. The state variables represent the inphase and quadrature components of the UWB channel. The expected maximization and extended Kalman filter are employed to recursively identify and estimate the channel parameters and states, respectively, from online received signal strength measured data. Both resolvable and non-resolvable multipath received signals are considered and represented as small-scaled Nakagami fading. The proposed models together with the estimation algorithm are tested using UWB indoor measurement data demonstrating the method s viability and the results are presented.

  12. Generalized decoding, effective channels, and simplified security proofs in quantum key distribution

    SciTech Connect (OSTI)

    Renes, Joseph M. [IAKS Prof. Beth, Arbeitsgruppe Quantum Computing, Universitaet Karlsruhe, Am Fasanengarten 5, D-76131 Karlsruhe (Germany); Quantum Information Theory Group, Institut fuer Theoretische Physik I, and Max-Planck-Forschungsgruppe, Institut fuer Optik, Information und Photonik, Universitaet Erlangen-Nuernberg, Staudtstrasse 7, D-91058 Erlangen (Germany); Grassl, Markus [IAKS Prof. Beth, Arbeitsgruppe Quantum Computing, Universitaet Karlsruhe, Am Fasanengarten 5, D-76131 Karlsruhe (Germany)

    2006-08-15T23:59:59.000Z

    Prepare and measure quantum key distribution protocols can be decomposed into two basic steps: delivery of the signals over a quantum channel and distillation of a secret key from the signal and measurement records by classical processing and public communication. Here we formalize the distillation process for a general protocol in a purely quantum-mechanical framework and demonstrate that it can be viewed as creating an 'effective' quantum channel between the legitimate users Alice and Bob. The process of secret key generation can then be viewed as entanglement distribution using this channel, which enables application of entanglement-based security proofs to essentially any prepare and measure protocol. To ensure secrecy of the key, Alice and Bob must be able to estimate the channel noise from errors in the key, and we further show how symmetries of the distillation process simplify this task. Applying this method, we prove the security of several key distribution protocols based on equiangular spherical codes.

  13. arterial wave mechanics: Topics by E-print Network

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

    polarization and entanglement) of multi-photon states propagating through inhomogeneous media. As a demonstration of the two-photon wave function's use, we show how two photons...

  14. This book describes the responsibilities of show personnel and outlines the job descriptions of various positions for the NH 4-H State Horse Show (or any other 4-H horse show).

    E-Print Network [OSTI]

    New Hampshire, University of

    of various positions for the NH 4-H State Horse Show (or any other 4-H horse show). June 2013 #12;Table of Contents Organizing a 4-H Horse Show ........................................................................................... 1 State 4-H Horse Show Philosophy................................................................ 1

  15. General teleportation channel, singlet fraction and quasi-distillation

    E-Print Network [OSTI]

    Horodecki, M; Horodecki, R; Horodecki, Michal; Horodecki, Pawel; Horodecki, Ryszard

    1999-01-01T23:59:59.000Z

    We prove a theorem on direct relation between the optimal fidelity $f_{max}$ of teleportation and the maximal singlet fraction $F_{max}$ attainable by means of trace-preserving LQCC action (local quantum and classical communication). For a given bipartite state acting on $C^d\\otimes C^d$ we have $f_{max}= {F_{max}d+1\\over d+1}$. We assume completely arbitrary teleportation schemes (trace preserving LQCC action over the pair and the third particle in unknown state). The proof involves the isomorphism between quantum channels and a class of bipartite states. We also exploit the technique of $U\\otimes U^*$ twirling states (random application of unitary transformation of the above form) and the introduced analogous twirling of channels. We illustrate the power of the theorem by showing that {\\it any} bound entangled state does not provide better fidelity of teleportation than for the purely classical channel. Subsequently, we apply our tools to the problem of the so-called conclusive teleportation, then reduced t...

  16. Message passing with queues and channels

    DOE Patents [OSTI]

    Dozsa, Gabor J; Heidelberger, Philip; Kumar, Sameer; Ratterman, Joseph D; Steinmacher-Burow, Burkhard; Wisniewski, Robert W

    2013-09-24T23:59:59.000Z

    In an embodiment, a send thread receives an identifier that identifies a destination node and a pointer to data. The send thread creates a first send request in response to the receipt of the identifier and the data pointer. The send thread selects a selected channel from among a plurality of channels. The selected channel comprises a selected hand-off queue and an identification of a selected message unit. Each of the channels identifies a different message unit. The selected hand-off queue is randomly accessible. If the selected hand-off queue contains an available entry, the send thread adds the first send request to the selected hand-off queue. If the selected hand-off queue does not contain an available entry, the send thread removes a second send request from the selected hand-off queue and sends the second send request to the selected message unit.

  17. Channel modelling and relay for powerline communications 

    E-Print Network [OSTI]

    Tan, Bo

    2013-11-28T23:59:59.000Z

    The thesis discusses the channel modelling and relay techniques in powerline communications (PLC) which is considered as a promising technology for the Smart Grid communications, Internet access and home area network ...

  18. Active Brownian motion in a narrow channel

    E-Print Network [OSTI]

    Xue Ao; Pulak Kumar Ghosh; Yunyun Li; Gerhard Schmid; Peter Hänggi; Fabio Marchesoni

    2014-09-17T23:59:59.000Z

    We review recent advances in rectification control of artificial microswimmers, also known as Janus particles, diffusing along narrow, periodically corrugated channels. The swimmer self-propulsion mechanism is modeled so as to incorporate a nonzero torque (propulsion chirality). We first summarize the effects of chirality on the autonomous current of microswimmers freely diffusing in channels of different geometries. In particular, left-right and upside-down asymmetric channels are shown to exhibit different transport properties. We then report new results on the dependence of the diffusivity of chiral microswimmers on the channel geometry and their own self-propulsion mechanism. The self-propulsion torque turns out to play a key role as a transport control parameter.

  19. Two-way quantum communication channels

    E-Print Network [OSTI]

    Childs, A M; Lo, H K; Childs, Andrew M.; Leung, Debbie W.; Lo, Hoi-Kwong

    2005-01-01T23:59:59.000Z

    We consider communication between two parties using a bipartite quantum operation, which constitutes the most general quantum mechanical model of two-party communication. We primarily focus on the simultaneous forward and backward communication of classical messages. For the case in which the two parties share unlimited prior entanglement, we give inner and outer bounds on the achievable rate region that generalize classical results due to Shannon. In particular, using a protocol of Bennett, Harrow, Leung, and Smolin, we give a one-shot expression in terms of the Holevo information for the entanglement-assisted one-way capacity of a two-way quantum channel. As applications, we rederive two known additivity results for one-way channel capacities: the entanglement-assisted capacity of a general one-way channel, and the unassisted capacity of an entanglement-breaking one-way channel.

  20. Kelp Forests of the Santa Barbara Channel

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Kelp Forests of the Santa Barbara Channel Revised Fourth Edition Kelp Forests of the Santa Barbara Research Program Santa Barbara Coastal Long Term Ecological Research Program #12;Kelp Forests of the Santa

  1. Optimal Distributed Beamforming for MISO Interference Channels

    E-Print Network [OSTI]

    Qiu, Jiaming

    2012-07-16T23:59:59.000Z

    In this thesis, the problem of quantifying the Pareto optimal boundary of the achievable rate region is considered over multiple-input single-output(MISO)interference channels, where the problem boils down to solving a sequence of convex feasibility...

  2. Distributed computation on unreliable radio channels

    E-Print Network [OSTI]

    Newport, Calvin (Calvin Charles)

    2009-01-01T23:59:59.000Z

    An important topic in wireless networking is the development of reliable algorithms for environments suffering from adversarial interference. This term captures any type of channel disruption outside the control of the ...

  3. Time varying channels : characterization, estimation, and detection

    E-Print Network [OSTI]

    Ricklin, Nathan D.

    2010-01-01T23:59:59.000Z

    overall, then the Doppler’s effect of smearing the symbol into note the effect on normalized Doppler of increasing theis the ICI, a direct effect of the Doppler induced channel

  4. Electrokinetic Energy Conversion Efficiency in Nanofluidic Channels

    E-Print Network [OSTI]

    Dekker, Cees

    Electrokinetic Energy Conversion Efficiency in Nanofluidic Channels Frank H. J. van der Heyden- and nanofluidic devices2-5 whose geometries and material properties can be engineered. High energy

  5. Transverse flow in thin superhydrophobic channels

    E-Print Network [OSTI]

    Feuillebois, Francois

    We provide some general theoretical results to guide the optimization of transverse hydrodynamic phenomena in superhydrophobic channels. Our focus is on the canonical micro- and nanofluidic geometry of a parallel-plate ...

  6. Light Show

    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 PowerCherries 82981-1cnHigh SchoolIn12electron 9 5Let us count theLienertLift Forces in9 Lightning

  7. Employee Show

    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 3,625govInstrumentstdmadapInactiveVisitingContractElectron-State HybridizationSecurity /MaterialsPKGWhere Science

  8. Digitally Assisted Multi-Channel Receivers

    E-Print Network [OSTI]

    Pentakota, Krishna Anand Santosh Spikanth

    2011-10-21T23:59:59.000Z

    -channel charge sampling receivers with sinc filter banks together with a complete system calibration and synchronization algorithm for the receiver. A unified model has been defined for the receiver containing all first order mismatches, offsets... and imperfections and a technique based on least mean squares algorithm is employed to track these errors. The performance of this technique under noisy channel conditions has been verified. The sinc filter bank is compared with the conventional analog filter...

  9. Quatum Thermodynamics and the coherence in Ion channels

    E-Print Network [OSTI]

    Samyadeb Bhattacharya; Sisir Roy

    2013-05-02T23:59:59.000Z

    We showed that quantum mechanical superposition can sustain in the process of ion transfer in protein membrane for a substantial period, in spite of the presence of the interactions with environmental modes of molecular vibration. The spectral temperature, as defined in quantum thermodynamical framework plays a significant role in maintaining the coherence. The ratio of decoherence time and dwell time has been calculated, which can be directly related to the degree of coherence. The results shead new light to build quantum information system of entangled ionic states in the voltage gated biological channels.

  10. MISO Broadcast Channel with Delayed and Evolving CSIT

    E-Print Network [OSTI]

    Gesbert, David

    MISO Broadcast Channel with Delayed and Evolving CSIT Jinyuan Chen and Petros Elia Mobile--The work considers the two-user MISO broadcast channel with a gradual and delayed accumulation of channel-input single-output broadcast channel (MISO BC) with an M-transmit antenna (M 2) transmitter communicating

  11. FLUID: Improving Throughputs in Enterprise Wireless LANs through Flexible Channelization

    E-Print Network [OSTI]

    Liblit, Ben

    the usefulness of flexible channels in the context of 802.11-based networks. Current 802.11 hardware can provideFLUID: Improving Throughputs in Enterprise Wireless LANs through Flexible Channelization Shravan for designing 802.11 wireless LANs (WLANs) using flexible channelization -- the choice of an appropriate channel

  12. Ion Channels as Promising Therapeutic Targets for Melanoma

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    20 Ion Channels as Promising Therapeutic Targets for Melanoma Aurélie Chantôme1, Marie Potier. During the last decade, the number of ion- channel types expressed in various cancers, including melanoma;Breakthroughs in Melanoma Research430 class of channels, water channels or aquaporins (AQP), allow water

  13. A Reliable method for Blind Channel Identification using Burst Data

    E-Print Network [OSTI]

    Raphaeli, Dan

    1 A Reliable method for Blind Channel Identification using Burst Data Dan Raphaeli, Senior Member Output (MISO) FIR channels with nonminimum phase. The approach is based on mini- mizing a cost function of identification success when consider- ing statistical channels, its ability to obtain reliable channel estimates

  14. Clustering of cyclic-nucleotide-gated channels in olfactory cilia

    E-Print Network [OSTI]

    French, Donald A.

    Clustering of cyclic-nucleotide-gated channels in olfactory cilia Richard J. Flannery* , Donald A channel clusters in olfactory cilia Key words: olfaction, receptor neuron, cyclic-nucleotide-gated channel of olfactory signal transduction, including a high density of cyclic-nucleotide-gated (CNG) channels. CNG

  15. Multiple description source coding for mobile radio channels

    E-Print Network [OSTI]

    Pegnyemb, Telesphore Bertrand

    1999-01-01T23:59:59.000Z

    The topic of this thesis is the transmission of a memoryless source over a slow fading channel. It should be noted that when a channel is specified as a slow fading channel, it does not specify whether the channel is flat or frequency selective...

  16. MHD channel gas-side element erosion-corrosion studies

    SciTech Connect (OSTI)

    Pollina, R.J.; Simpsom, W. (Avco-Everett Research Lab., Inc., Everett, MA (USA)); Farrar, L.C. (Montec Associates, Inc., Butte, MT (USA))

    1990-01-01T23:59:59.000Z

    The problems connected with gas side corrosion for the design of the 1A4 channel hardware are explored and the authors present the results to date of gas side wear rate tests in the Mark 7 facility. They show that the proposed designs meet a 2000 hour lifetime criterion based upon materials test results. They also show the improvement in cathode lifetime obtained with lower voltage intercathode gaps. Finally the authors discuss the corrosion of these materials and show how lifetimes are dependent upon gap voltage and average metal temperature. The final choice of materials is determined primarily by the outcome of these tests and also by the question of the manufacturability of the prospective designs. 6 figs., 6 tabs.

  17. A Search for Channel Deformation in Irradiated Vanadium Tensile Specimens

    SciTech Connect (OSTI)

    Gelles, David S.; Toloczko, Mychailo B.; Kurtz, Richard J.

    2010-02-26T23:59:59.000Z

    A miniature tensile specimen of V-4Cr-4Ti which had be irradiated in the 17J test at 425°C to 3.7 dpa was mechanically polished, deformed to 3.9% strain at room temperature, and examined by scanning and transmission electron microscopy in order to look for evidence of channel deformation. It was found that uniform deformation can occur without channel deformation, but evidence for channeling was found with channels appearing most prominently after the onset of necking. The channeling occurs on wavy planes with large variations in localized deformation from channel to channel.

  18. Poly(ethylene glycol)-based open-channel blockers for the acetylcholine receptor : mechanistic and structure-function studies at the single-channel level

    E-Print Network [OSTI]

    Lin, Wan-Chen, Ph. D. Massachusetts Institute of Technology

    2009-01-01T23:59:59.000Z

    Ion channels are essential mediators in nervous signaling pathways. Because hyperactivation of ion channels can lead to pathological disorders such as congenital myasthenic syndromes and neurodegeneration, channel inhibitors ...

  19. Single- and coupled-channel radial inverse scattering with supersymmetric transformations

    E-Print Network [OSTI]

    Daniel Baye; Jean-Marc Sparenberg; Andrey M Pupasov-Maksimov; Boris F Samsonov

    2014-06-13T23:59:59.000Z

    The present status of the coupled-channel inverse-scattering method with supersymmetric transformations is reviewed. We first revisit in a pedagogical way the single-channel case, where the supersymmetric approach is shown to provide a complete solution to the inverse-scattering problem. A special emphasis is put on the differences between conservative and non-conservative transformations. In particular, we show that for the zero initial potential, a non-conservative transformation is always equivalent to a pair of conservative transformations. These single-channel results are illustrated on the inversion of the neutron-proton triplet eigenphase shifts for the S and D waves. We then summarize and extend our previous works on the coupled-channel case and stress remaining difficulties and open questions. We mostly concentrate on two-channel examples to illustrate general principles while keeping mathematics as simple as possible. In particular, we discuss the difference between the equal-threshold and different-threshold problems. For equal thresholds, conservative transformations can provide non-diagonal Jost and scattering matrices. Iterations of such transformations are shown to lead to practical algorithms for inversion. A convenient technique where the mixing parameter is fitted independently of the eigenphases is developed with iterations of pairs of conjugate transformations and applied to the neutron-proton triplet S-D scattering matrix, for which exactly-solvable matrix potential models are constructed. For different thresholds, conservative transformations do not seem to be able to provide a non-trivial coupling between channels. In contrast, a single non-conservative transformation can generate coupled-channel potentials starting from the zero potential and is a promising first step towards a full solution to the coupled-channel inverse problem with threshold differences.

  20. Quantum steganography with noisy quantum channels

    SciTech Connect (OSTI)

    Shaw, Bilal A. [Department of Computer Science, University of Southern California, Los Angeles, California 90089 (United States); Center for Quantum Information Science and Technology, University of Southern California, Los Angeles, California 90089 (United States); Brun, Todd A. [Department of Computer Science, University of Southern California, Los Angeles, California 90089 (United States); Center for Quantum Information Science and Technology, University of Southern California, Los Angeles, California 90089 (United States); Department of Electrical Engineering, University of Southern California, Los Angeles, California 90089 (United States); Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089 (United States)

    2011-02-15T23:59:59.000Z

    Steganography is the technique of hiding secret information by embedding it in a seemingly ''innocent'' message. We present protocols for hiding quantum information by disguising it as noise in a codeword of a quantum error-correcting code. The sender (Alice) swaps quantum information into the codeword and applies a random choice of unitary operation, drawing on a secret random key she shares with the receiver (Bob). Using the key, Bob can retrieve the information, but an eavesdropper (Eve) with the power to monitor the channel, but without the secret key, cannot distinguish the message from channel noise. We consider two types of protocols: one in which the hidden quantum information is stored locally in the codeword, and another in which it is embedded in the space of error syndromes. We analyze how difficult it is for Eve to detect the presence of secret messages, and estimate rates of steganographic communication and secret key consumption for specific protocols and examples of error channels. We consider both the case where there is no actual noise in the channel (so that all errors in the codeword result from the deliberate actions of Alice), and the case where the channel is noisy and not controlled by Alice and Bob.

  1. Determinating Timing Channels in Statistically Multiplexed Clouds

    E-Print Network [OSTI]

    Aviram, Amittai; Ford, Bryan; Gummadi, Ramakrishna

    2010-01-01T23:59:59.000Z

    Timing side-channels represent an insidious security challenge for cloud computing, because: (a) they enable one customer to steal information from another without leaving a trail or raising alarms; (b) only the cloud provider can feasibly detect and report such attacks, but the provider's incentives are not to; and (c) known general-purpose timing channel control methods undermine statistical resource sharing efficiency, and, with it, the cloud computing business model. We propose a new cloud architecture that uses provider-enforced deterministic execution to eliminate all timing channels internal to a shared cloud domain, without limiting internal resource sharing. A prototype determinism-enforcing hypervisor demonstrates that utilizing such a cloud might be both convenient and efficient. The hypervisor enables parallel guest processes and threads to interact via familiar shared memory and file system abstractions, and runs moderately coarse-grained parallel tasks as efficiently and scalably as current nond...

  2. Transverse flow in thin superhydrophobic channels

    E-Print Network [OSTI]

    Feuillebois, Francois; Vinogradova, Olga I

    2010-01-01T23:59:59.000Z

    We provide some general theoretical results to guide the optimization of transverse hydrodynamic phenomena in superhydrophobic channels. Our focus is on the canonical micro- and nanofluidic geometry of a parallel-plate channel with an arbitrary two-component (low-slip and high-slip) coarse texture, varying on scales larger than the channel thickness. By analyzing rigorous bounds on the permeability, over all possible patterns, we optimize the area fractions, slip lengths, geometry and orientation of the surface texture to maximize transverse flow. In the case of two aligned striped surfaces, very strong transverse flows are possible. Optimized superhydrophobic surfaces may find applications in passive microfluidic mixing and amplification of transverse electrokinetic phenomena.

  3. A study of the eta etaprime and etaprime etaprime channels produced in central pp interactions at 450 GeV/c

    E-Print Network [OSTI]

    The WA102 Collaboration; D. Barberis

    1999-11-29T23:59:59.000Z

    The reactions pp -> pf (X0) ps, where X0 is observed decaying to eta etaprime and etaprime etaprime, have been studied at 450 GeV/c. This is the first time that these channels have been observed in central production and only the second time that the etaprime etaprime channel has been observed in any production mechanism. In the eta etaprime channel there is evidence for the f0(1500) and a peak at 1.95 GeV. The etaprime etaprime channel shows a peak at threshold which is compatible with having JPC = 2++ and spin projection JZ = 0.

  4. Blind CFO estimation for OFDM-IDMA system in Rayleigh fading multipath channel

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    - 1 - Blind CFO estimation for OFDM-IDMA system in Rayleigh fading multipath channel Yasamine to adapt a method of blind CFO estimation, called CFO estimation-Syndrome Function Minimization (C- SFM show that, for high Eb/N0, the two systems have the same performance. Key words: Blind carrier

  5. Beamforming for the Underlay Cognitive MISO Interference Channel via UL-DL Duality

    E-Print Network [OSTI]

    Gesbert, David

    Beamforming for the Underlay Cognitive MISO Interference Channel via UL-DL Duality Francesco Negro.negro@eurecom.fr, dirk.slock@eurecom.fr Abstract--SINR duality is shown in a multi-input single- output (MISO) downlink for the IFC. We show that SINR duality under the sum power constraint nevertheless holds in the MISO IFC

  6. Rate Shaping by Block Dropping for Transmission of MPEGprecoded Video over Channels of Dynamic Bandwidth

    E-Print Network [OSTI]

    Zeng, Wenjun "Kevin"

    ) and much better visual quality than conventional ap­ proaches. We also show that by jointly dropping blocksRate Shaping by Block Dropping for Transmission of MPEG­precoded Video over Channels of Dynamic of the compressed video in cases that the network capacity is reduced. This pa­ per proposes a novel block

  7. Remote control of ion channels and neurons through magnetic-field heating of nanoparticles

    E-Print Network [OSTI]

    Ferkey, Denise

    Remote control of ion channels and neurons through magnetic-field heating of nanoparticles Heng. Here, we show an approach based on radio-frequency magnetic-field heating of nanoparticles to remotely targeted to specific proteins on the plasma membrane of cells expressing TRPV1, and heated by a radio

  8. Nonlinear Trellis Description for Convolutionally Encoded Transmission Over ISI-channels with Applications for CPM

    E-Print Network [OSTI]

    Schuh, Fabian

    2012-01-01T23:59:59.000Z

    In this paper we propose a matched decoding scheme for convolutionally encoded transmission over intersymbol interference (ISI) channels and devise a nonlinear trellis description. As an application we show that for coded continuous phase modulation (CPM) using a non-coherent receiver the number of states of the super trellis can be significantly reduced by means of a matched non-linear trellis encoder.

  9. Quantum capacity of lossy channel with additive classical Gaussian noise : a perturbation approach

    E-Print Network [OSTI]

    Xiao-yu Chen

    2007-10-02T23:59:59.000Z

    For a quantum channel of additive Gaussian noise with loss, in the general case of $n$ copies input, we show that up to first order perturbation, any non-Gaussian perturbation to the product thermal state input has a less quantum information transmission rate when the input energy tend to infinitive.

  10. Unconditional Security of the Bennett 1992 quantum key-distribution over lossy and noisy channel

    E-Print Network [OSTI]

    Kiyoshi Tamaki; Norbert Lütkenhaus

    2003-08-11T23:59:59.000Z

    We show that the security proof of the Bennett 1992 protocol over loss-free channel in (K. Tamaki, M. Koashi, and N. Imoto, Phys. Rev. Lett. 90, 167904 (2003)) can be adapted to accommodate loss. We assumed that Bob's detectors discriminate between single photon states on one hand and vacuum state or multi-photon states on the other hand.

  11. Positivity, Discontinuity, Finite Resources and Nonzero Error for Arbitrarily Varying Quantum Channels

    E-Print Network [OSTI]

    H. Boche; J. Noetzel

    2014-05-07T23:59:59.000Z

    This work is motivated by a quite general question: Under which circumstances are the capacities of information transmission systems continuous? The research is explicitly carried out on arbitrarily varying quantum channels (AVQCs). We give an explicit example that answers the recent question whether the transmission of messages over AVQCs can benefit from distribution of randomness between the legitimate sender and receiver in the affirmative. The specific class of channels introduced in that example is then extended to show that the deterministic capacity does have discontinuity points, while that behaviour is, at the same time, not generic: We show that it is continuous around its positivity points. This is in stark contrast to the randomness-assisted capacity, which is always continuous in the channel. Our results imply that the deterministic message transmission capacity of an AVQC can be discontinuous only in points where it is zero, while the randomness assisted capacity is nonzero. Apart from the zero-error capacities, this is the first result that shows a discontinuity of a capacity for a large class of quantum channels. The continuity of the respective capacity for memoryless quantum channels had, among others, been listed as an open problem on the problem page of the ITP Hannover for about six years before it was proven to be continuous. We also quantify the interplay between the distribution of finite amounts of randomness between the legitimate sender and receiver, the (nonzero) decoding error with respect to the average error criterion that can be achieved over a finite number of channel uses and the number of messages that can be sent. This part of our results also applies to entanglement- and strong subspace transmission. In addition, we give a new sufficient criterion for the entanglement transmission capacity with randomness assistance to vanish.

  12. Heat transfer and flow characteristics of cooling channels in turbine blades

    E-Print Network [OSTI]

    Saxena, Amit

    1988-01-01T23:59:59.000Z

    /mass transfer distributions were determined for straight flow' through a pin fin channel (H/D = 1, S/D = X/D = 2. 5) and a flow through the pin fin channel with trailing edge flow ejection. The overall friction factor and local pressure drop results were... obtained for various configurations and lengths (L/d = 2 and 20) of the trailing edge ejection holes, From the pressure drop data, the radial mass flow rate and the mass flow rates through trailing edge ejection holes were calculated. The results show...

  13. Donor doping of single-walled carbon nanotubes by filling of channels with silver

    SciTech Connect (OSTI)

    Kharlamova, M. V., E-mail: mv.kharlamova@gmail.com [Moscow State University (Russian Federation); Niu, J. J. [Drexel University, Department of Materials Science and Engineering (United States)

    2012-09-15T23:59:59.000Z

    The channels of single-walled carbon nanotubes (SWNTs) are filled with metallic silver. The synthesized nanocomposites are studied by Raman spectroscopy and optical absorption spectroscopy, and these data indicate a substantial modification of the electronic structure of the nanotubes upon their filling. Moreover, X-ray photoelectron spectroscopy shows that the incorporation of the metal leads to a change in the work function of SWNTs due to the Fermi level upshift and to the transfer of an electron density from inserted nanoparticles to the nanotube walls. Thus, the filling of the channels with silver results in donor doping of the nanotubes.

  14. Laboratory measurements of wave height variations and currents along a steep-sided channel

    E-Print Network [OSTI]

    Way, Francis

    2000-01-01T23:59:59.000Z

    towards the channel, when the basin is filling. The channel is evident by the dark rectangle in the middle of the figure. 16 3. 3: Truncated time series of case 1 atx=2. 5m andy=8. 0 m (55&t(70 s). The open circle in figure 3. 1 shows the measurement... position in the basin. . . . . . . . . . . . . . 19 3. 4: The ADV's side-looking 3-D sensor probe 20 3. 5: Plan view of where ADV measurements were taken. The circle indicates a representative location that is referred to in Figure 3. 6...

  15. FREEPORT HARBOR, TEXAS CHANNEL IMPROVEMENT PROJECT

    E-Print Network [OSTI]

    US Army Corps of Engineers

    by 2021. Dredged material management will be performed in the least cost manner according to the Dredged. The study evaluated project benefits based on reduction in transportation costs generated from more feet wide; and dredging the remainder of the Stauffer Channel to a depth of -25 feet MLT (-26 feet MLLW

  16. FREEPORT HARBOR, TEXAS CHANNEL IMPROVEMENT PROJECT

    E-Print Network [OSTI]

    US Army Corps of Engineers

    on reduction in transportation costs generated from more efficient loading of the existing fleet, from (-51 feet MLLW) and 300 feet wide; and dredging the remainder of the Stauffer Channel to a depth of -25 require eight separate dredging contracts to complete. The work is estimated to begin in 2012

  17. Differential Kalman Filteringfor Tracking Rayleigh Fading Channels

    E-Print Network [OSTI]

    Gulak, P. Glenn

    Differential Kalman Filteringfor Tracking Rayleigh Fading Channels M. J. Ornidi,S.Gazol;F? G. Gulak in the tracking of a fadingchannel plays an essential role in many wireless receivers. The conventional Kalman implementation. In this paper a new approach is proposed for the implementation of the Kalman filter based

  18. Transformer Recharging with Alpha Channeling in Tokamaks

    SciTech Connect (OSTI)

    N.J. Fisch

    2009-12-21T23:59:59.000Z

    Transformer recharging with lower hybrid waves in tokamaks can give low average auxiliary power if the resistivity is kept high enough during the radio frequency (rf) recharging stage. At the same time, operation in the hot ion mode via alpha channeling increases the effective fusion reactivity. This paper will address the extent to which these two large cost saving steps are compatible. __________________________________________________

  19. Channel Routing for Integrated Optics Christopher Condrat

    E-Print Network [OSTI]

    Kalla, Priyank

    Channel Routing for Integrated Optics Christopher Condrat (chris@g6net.com) Priyank Kalla (kalla, Salt Lake City, UT, USA Abstract--Increasing scope and applications of integrated optics necessitates the development of automated techniques for physical design of optical systems. This paper presents an automated

  20. Variational Bayesian Blind and Semiblind Channel Estimation

    E-Print Network [OSTI]

    Gesbert, David

    elaborate the details for the case of MIMO OFDM systems. I. INTRODUCTION Blind and semiblind channel, SFR , Orange, STEricsson, Cisco, BMW Group , SAP, Monaco Telecom and Symantec. The research reported herein has also been partially supported by the European FP7 NoE NewCom++ and FET project CROWN

  1. Computational Studies of the Gramicidin Channel

    E-Print Network [OSTI]

    Gates, Kent. S.

    Medical College of Cornell University, 1300 York Avenue, New York, New York 10021 Received September 17 of the ion and water molecules through the channel interior, the large energetic loss due to dehydration, the large energetic loss of de- hydration being roughly compensated by coordination with main-chain carbonyl

  2. Four-Channel Differential AC Amplifier

    E-Print Network [OSTI]

    Kleinfeld, David

    to amplify cellular neurophysiological signals in applications requiring high gain, high input impedance, low://www.a-msystems.com General Description Instrument Features The Four-Channel Differential AC Amplifier Model 1700 is designed noise, high common-mode rejection, and powerline interference rejection. Typical applications include

  3. Channel coding for high speed links

    E-Print Network [OSTI]

    Blitvic, Natasa

    2008-01-01T23:59:59.000Z

    This thesis explores the benefit of channel coding for high-speed backplane or chip-to-chip interconnects, referred to as the high-speed links. Although both power-constrained and bandwidth-limited, the high-speed links ...

  4. Quaternary Ammonium Compounds as Water Channel Blockers

    E-Print Network [OSTI]

    de Groot, Bert

    /AQP2/AQP4, whereas the water permeability of AQP3 and AQP5, which lack a corresponding TyrQuaternary Ammonium Compounds as Water Channel Blockers SPECIFICITY, POTENCY, AND SITE OF ACTION, West Mains Road, EH9 3JJ Scotland, United Kingdom Excessive water uptake through Aquaporins (AQP) can

  5. Heat transfer and pressure drop in an annular channel with downflow

    SciTech Connect (OSTI)

    Dolan, F.X.; Crowley, C.J. (Creare, Inc., Hanover, NH (United States)); Qureshi, Z.H. (Westinghouse Savannah River Co., Aiken, SC (United States))

    1992-01-01T23:59:59.000Z

    The onset of a flow instability (OFI) determines the minimum flow rate for cooling in the flow channels of a nuclear fuel assembly. A test facility was constructed with full-scale models (length and diameter) of annular flow channels incorporating many instruments to measure heat transfer and pressure drop with downflow in the annulus. Tests were performed both with and without axial centering ribs at prototypical values of pressure, flow rate and uniform wall heat flux. The axial ribs have the effect of subdividing the annulus into quadrants, so the problem becomes one of parallel channel flow, unlike previous experiments in tubes (upflow and downflow). Other tests were performed to determine the effects if any of asymmetric and non-uniform circumferential wall heating, operating pressure level and dissolved gas concentration. Data from the tests are compared with models for channel heat transfer and pressure drop profiles in several regimes of wall heating from single-phase forced convection through partially and fully developed nucleate boiling. Minimum stable flow rates were experimentally determined as a function of wall heat flux and heat distribution and compared with the model for the transition to fully developed boiling which is a key criterion in determining the OFI condition in the channel. The heat transfer results in the channel without ribs are in excellent agreement with predictions from a computer model of the flow in the annulus and with empirical correlations developed from similar tests. The test results with centering ribs show that geometrical variations between the channels can lead to differences in subchannel behavior which can make the effect of the ribs and the geometry an important factor when assessing the power level at which the fuel assembly (and the reactor) can be operated to prevent overheating in the event of a loss-of-coolant-accident (LOCA).

  6. Heat transfer and pressure drop in an annular channel with downflow

    SciTech Connect (OSTI)

    Dolan, F.X.; Crowley, C.J. [Creare, Inc., Hanover, NH (United States); Qureshi, Z.H. [Westinghouse Savannah River Co., Aiken, SC (United States)

    1992-06-01T23:59:59.000Z

    The onset of a flow instability (OFI) determines the minimum flow rate for cooling in the flow channels of a nuclear fuel assembly. A test facility was constructed with full-scale models (length and diameter) of annular flow channels incorporating many instruments to measure heat transfer and pressure drop with downflow in the annulus. Tests were performed both with and without axial centering ribs at prototypical values of pressure, flow rate and uniform wall heat flux. The axial ribs have the effect of subdividing the annulus into quadrants, so the problem becomes one of parallel channel flow, unlike previous experiments in tubes (upflow and downflow). Other tests were performed to determine the effects if any of asymmetric and non-uniform circumferential wall heating, operating pressure level and dissolved gas concentration. Data from the tests are compared with models for channel heat transfer and pressure drop profiles in several regimes of wall heating from single-phase forced convection through partially and fully developed nucleate boiling. Minimum stable flow rates were experimentally determined as a function of wall heat flux and heat distribution and compared with the model for the transition to fully developed boiling which is a key criterion in determining the OFI condition in the channel. The heat transfer results in the channel without ribs are in excellent agreement with predictions from a computer model of the flow in the annulus and with empirical correlations developed from similar tests. The test results with centering ribs show that geometrical variations between the channels can lead to differences in subchannel behavior which can make the effect of the ribs and the geometry an important factor when assessing the power level at which the fuel assembly (and the reactor) can be operated to prevent overheating in the event of a loss-of-coolant-accident (LOCA).

  7. New bounding techniques for channel codes over quasi-static fading channels 

    E-Print Network [OSTI]

    Hu, Jingyu

    2005-04-01T23:59:59.000Z

    reliable wireless communication systems. Although there have been some published results on analyzing the performance of channel codes over QSFCs, most of them produced quite loose performance upper bounds. In this thesis, the general Gallager bounding...

  8. Channel Sounding for the Masses: Low Complexity GNU 802.11b Channel Impulse Response Estimation

    E-Print Network [OSTI]

    Firooz, Mohammad H; Zhang, Junxing; Patwari, Neal; Kasera, Sneha K

    2010-01-01T23:59:59.000Z

    New techniques in cross-layer wireless networks are building demand for ubiquitous channel sounding, that is, the capability to measure channel impulse response (CIR) with any standard wireless network and node. Towards that goal, we present a software-defined IEEE 802.11b receiver and CIR estimation system with little additional computational complexity compared to 802.11b reception alone. The system implementation, using the universal software radio peripheral (USRP) and GNU Radio, is described and compared to previous work. By overcoming computational limitations and performing direct-sequence spread-spectrum (DS-SS) matched filtering on the USRP, we enable high-quality yet inexpensive CIR estimation. We validate the channel sounder and present a drive test campaign which measures hundreds of channels between WiFi access points and an in-vehicle receiver in urban and suburban areas.

  9. Resonant behaviour of an oscillating wave energy converter in a channel

    E-Print Network [OSTI]

    E. Renzi; F. Dias

    2012-04-10T23:59:59.000Z

    A mathematical model is developed to study the behaviour of an oscillating wave energy converter in a channel. During recent laboratory tests in a wave tank, peaks in the hydrodynamic actions on the converter occurred at certain frequencies of the incident waves. This resonant mechanism is known to be generated by the transverse sloshing modes of the channel. Here the influence of the channel sloshing modes on the performance of the device is further investigated. Within the framework of a linear inviscid potential-flow theory, application of the Green theorem yields a hypersingular integral equation for the velocity potential in the fluid domain. The solution is found in terms of a fast-converging series of Chebyshev polynomials of the second kind. The physical behaviour of the system is then analysed, showing sensitivity of the resonant sloshing modes to the geometry of the device, that concurs in increasing the maximum efficiency. Analytical results are validated with available numerical and experimental data.

  10. Resonant behaviour of an oscillating wave energy converter in a channel

    E-Print Network [OSTI]

    Renzi, E

    2012-01-01T23:59:59.000Z

    A mathematical model is developed to study the behaviour of an oscillating wave energy converter in a channel. During recent laboratory tests in a wave tank, peaks in the hydrodynamic actions on the converter occurred at certain frequencies of the incident waves. This resonant mechanism is known to be generated by the transverse sloshing modes of the channel. Here the influence of the channel sloshing modes on the performance of the device is further investigated. Within the framework of a linear inviscid potential-flow theory, application of the Green theorem yields a hypersingular integral equation for the velocity potential in the fluid domain. The solution is found in terms of a fast-converging series of Chebyshev polynomials of the second kind. The physical behaviour of the system is then analysed, showing sensitivity of the resonant sloshing modes to the geometry of the device, that concurs in increasing the maximum efficiency. Analytical results are validated with available numerical and experimental d...

  11. Energetics of ion competition in the DEKA selectivity filter of neuronal sodium channels

    E-Print Network [OSTI]

    D. Boda; G. Leaf; J. Fonseca; B. Eisenberg

    2015-04-03T23:59:59.000Z

    The energetics of ionic selectivity in the neuronal sodium channels is studied. A simple model constructed for the selectivity filter of the channel is used. The selectivity filter of this channel type contains aspartate (D), glutamate (E), lysine (K), and alanine (A) residues (the DEKA locus). We use Grand Canonical Monte Carlo simulations to compute equilibrium binding selectivity in the selectivity filter and to obtain various terms of the excess chemical potential from a particle insertion procedure based on Widom's method. We show that K$^{+}$ ions in competition with Na$^{+}$ are efficiently excluded from the selectivity filter due to entropic hard sphere exclusion. The dielectric constant of protein has no effect on this selectivity. Ca$^{2+}$ ions, on the other hand, are excluded from the filter due to a free energetic penalty which is enhanced by the low dielectric constant of protein.

  12. Precision studies of the Higgs boson decay channel H ? Z Z ? 4 ? with MEKD

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

    Avery, Paul; Bourilkov, Dimitri; Chen, Mingshui; Cheng, Tongguang; Drozdetskiy, Alexey; Gainer, James S.; Korytov, Andrey; Matchev, Konstantin T.; Milenovic, Predrag; Mitselmakher, Guenakh; Park, Myeonghun; Rinkevicius, Aurelijus; Snowball, Matthew

    2013-03-01T23:59:59.000Z

    The importance of the H?ZZ?4l “golden” channel was shown by its major role in the discovery, by the ATLAS and CMS collaborations, of a Higgs-like boson with mass near 125 GeV. We analyze the discrimination power of the matrix element method both for separating the signal from the irreducible ZZ background and for distinguishing various spin and parity hypotheses describing a signal in this channel. We show that the proper treatment of interference effects associated with permutations of identical leptons in the 4e and 4? final states plays an important role in achieving the best sensitivity in measuring the properties of the newly discovered boson. We provide a code, mekd, that calculates kinematic discriminants based on the full leading-order matrix elements and which will aid experimentalists and phenomenologists in their continuing studies of the H?ZZ?4l channel.

  13. Finite blocklength analysis of the MISO Coherent Block Fading Channel

    E-Print Network [OSTI]

    Collins, Austin Daniel

    2014-01-01T23:59:59.000Z

    The Coherent MISO Block Fading Channel is a wireless communication channel model in which the transmitter has access to multiple antennas while the receiver has access to one. This model is becoming increasingly important ...

  14. Correlation-based beamforming for multi-user MIMO channels

    E-Print Network [OSTI]

    Anderson, Adam L.

    2008-01-01T23:59:59.000Z

    W. Cheng and R. Murch, “MU-MISO transmission with limitedis found in [42] for the MISO channel or in [28] for theoutperforms DPC in the MISO broadcast channel. A similar

  15. Channel estimation and feedback for multiple antenna communication

    E-Print Network [OSTI]

    Murthy, Chandra Ramabhadra

    2006-01-01T23:59:59.000Z

    Schematic representation of a MISO system with beamformingcapacity of the correlated MISO channel with Q-EGT for di?Outage probability of the MISO channel with quantized EGT (t

  16. 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. ...

  17. Minimal Proton Channel Enables H2 Oxidation and Production with...

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

    Minimal Proton Channel Enables H2 Oxidation and Production with a Water-Soluble Nickel-Based Catalyst. Minimal Proton Channel Enables H2 Oxidation and Production with a...

  18. Analysis of global channel costs for the pharmaceutical industry

    E-Print Network [OSTI]

    Rimling, Eric C. (Eric Christopher)

    2009-01-01T23:59:59.000Z

    The pharmaceutical industry creates products which often have more than one supply chain channel, defined as a route through the supply chain network from sourcing to the end market. Each channel's specific cost characteristics ...

  19. Bedrock channel response to tetonic, climatic and eustatic forcings

    E-Print Network [OSTI]

    Snyder, Noah P

    2001-01-01T23:59:59.000Z

    The response of bedrock channels to external forcings is investigated in this thesis. The approach is to test and constrain a theoretical model for bedrock-channel incision based on shear stress using field data. The primary ...

  20. Channel Meander Migration in Large-Scale Physical Model Study 

    E-Print Network [OSTI]

    Yeh, Po Hung

    2010-10-12T23:59:59.000Z

    A set of large-scale laboratory experiments were conducted to study channel meander migration. Factors affecting the migration of banklines, including the ratio of curvature to channel width, bend angle, and the Froude ...

  1. Secret key agreement using asymmetry in channel state knowledge

    E-Print Network [OSTI]

    Wornell, Gregory W.

    We study secret-key agreement protocols over a wiretap channel controlled by a state parameter. The secret-key capacity is established when the wiretap channel is discrete and memoryless, the sender and receiver are both ...

  2. Secret-Key Generation Using Correlated Sources and Channels

    E-Print Network [OSTI]

    Khisti, Ashish

    We study the secret-key capacity in a joint source-channel coding setup-the terminals are connected over a discrete memoryless channel and have access to side information, modelled as a pair of discrete memoryless source ...

  3. Heat transfer augmentation in a rectangular channel with slit rib-turbulators on two opposite walls

    SciTech Connect (OSTI)

    Hwang, J.J. [Chung-Hua Polytechnic Inst., Hsinchu (Taiwan, Province of China). Dept. of Mechanical Engineering; Liou, T.M. [National Tsing-Hua Univ., Hsinchu (Taiwan, Province of China). Dept. of Power Mechanical Engineering

    1997-07-01T23:59:59.000Z

    The effect of slit ribs on heat transfer and friction in a rectangular channel is investigated experimentally. The slit ribs are arranged in-line on two opposite walls of the channel. Three rib open-area ratios ({beta} = 24, 37, and 46%), three rib pitch-to-height ratios (Pi/H = 10, 20, and 30), and two rib height-to-channel hydraulic diameter ratios (H/De = 0.081, and 0.162) are examined. The Reynolds number ranges from 10,000 to 50,000. Laser holographic interferometry is employed to measure the local heat transfer coefficients of the ribbed wall quantitatively, and observe the flow over the ribbed wall qualitatively. The results show that the slit rib has an advantage of avoiding hot spots. In addition, the heat transfer performance of the slit-ribbed channel is much better than that of the solid-ribbed channel. Semi-empirical correlations for friction and heat transfer are developed to account for rib spacings and open-area ratios. These correlations may be used in the design of turbine blade cooling passages.

  4. Structural Analyses of the Ankyrin Repeat Domain of TRPV6 and Related TRPV Ion Channels

    SciTech Connect (OSTI)

    Phelps, C.B.; Huang, R.J.; Lishko, P.V.; Wang, R.R.; Gaudet, R. (Harvard)

    2008-06-03T23:59:59.000Z

    Transient receptor potential (TRP) proteins are cation channels composed of a transmembrane domain flanked by large N- and C-terminal cytoplasmic domains. All members of the vanilloid family of TRP channels (TRPV) possess an N-terminal ankyrin repeat domain (ARD). The ARD of mammalian TRPV6, an important regulator of calcium uptake and homeostasis, is essential for channel assembly and regulation. The 1.7 A crystal structure of the TRPV6-ARD reveals conserved structural elements unique to the ARDs of TRPV proteins. First, a large twist between the fourth and fifth repeats is induced by residues conserved in all TRPV ARDs. Second, the third finger loop is the most variable region in sequence, length and conformation. In TRPV6, a number of putative regulatory phosphorylation sites map to the base of this third finger. Size exclusion chromatography and crystal packing indicate that the TRPV6-ARD does not assemble as a tetramer and is monomeric in solution. Adenosine triphosphate-agarose and calmodulin-agarose pull-down assays show that the TRPV6-ARD does not interact with either ligand, indicating a different functional role for the TRPV6-ARD than in the paralogous thermosensitive TRPV1 channel. Similar biochemical findings are also presented for the highly homologous mammalian TRPV5-ARD. The implications of the structural and biochemical data on the role of the ankyrin repeats in different TRPV channels are discussed.

  5. Linear Beamforming for the Spatially Correlated MISO broadcast channel

    E-Print Network [OSTI]

    Raghavan, Vasanthan; Hanly, Stephen

    2010-01-01T23:59:59.000Z

    A spatially correlated broadcast setting with M antennas at the base station and M users (each with a single antenna) is considered. We assume that the users have perfect channel information about their links and the base station has only statistical information about each user's link. The base station employs a linear beamforming strategy with one spatial eigen-mode allocated to each user. The goal of this work is to understand the structure of the beamforming vectors that maximize the ergodic sum-rate achieved by treating interference as noise. In the M = 2 case, we first fix the beamforming vectors and compute the ergodic sum-rate in closed-form as a function of the channel statistics. We then show that the optimal beamforming vectors are the dominant generalized eigenvectors of the covariance matrices of the two links. It is difficult to obtain intuition on the structure of the optimal beamforming vectors for M > 2 due to the complicated nature of the sum-rate expression. Nevertheless, in the case of asym...

  6. Corrosion and arc erosion in MHD channels. Final report

    SciTech Connect (OSTI)

    Rosa, R.J. [Montana State Univ., Bozeman, MT (United States). Dept. of Mechanical Engineering; Pollina, R.J. [Montana State Univ., Bozeman, MT (United States). Dept. of Mechanical Engineering]|[EG and G Energy Measurements, Inc., Las Vegas, NV (United States)

    1992-08-01T23:59:59.000Z

    The problems connected with gas side corrosion for the design of the lA4 (POC) channel hardware are explored and results of gas side wear rate tests in the Textron Mark VII facility are presented. It is shown that the proposed designs meet a 2000 hour lifetime criterion based upon these materials tests. Improvement in cathode lifetime is demonstrated with lower voltage intercathode gaps. The corrosion of these materials is discussed and it is shown how lifetimes are dependent upon gap voltage and average metal temperature. The importance of uniformity of slagging to the durability of the anode wall is demonstrated. The wear mechanism of the anodes in the MHD channel is analyzed. In addition to gas-side corrosion, the results of specific water corrosion tests of sidewall materials are discussed. All of the tests reported here were carried out to confirm the gas-side performance and the manufacturability of anode and sidewall designs and to address questions posed about the durability of tungsten-copper on the waterside. the results of water corrosion tests of the tungsten copper alloy sidewall material are presented to show that with proper control of waterside pH and, if necessary, dissolved oxygen, one can obtain reliable performance with no degradation of heat transfer with this material. The final choice of materials was determined primarily by the outcome of these tests and also by the question of the manufacturability of the prospective designs.

  7. Stochastic Wireless Channel Modeling, Estimation and Identification from Measurements

    SciTech Connect (OSTI)

    Olama, Mohammed M [ORNL; Djouadi, Seddik M [ORNL; Li, Yanyan [ORNL

    2008-07-01T23:59:59.000Z

    This paper is concerned with stochastic modeling of wireless fading channels, parameter estimation, and system identification from measurement data. Wireless channels are represented by stochastic state-space form, whose parameters and state variables are estimated using the expectation maximization algorithm and Kalman filtering, respectively. The latter are carried out solely from received signal measurements. These algorithms estimate the channel inphase and quadrature components and identify the channel parameters recursively. The proposed algorithm is tested using measurement data, and the results are presented.

  8. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    the MICE cooling channel magnets and the progress in theProgress on the Superconducting Magnets for the MICE Cooling

  9. Free Online Training on the DVU Learning Channel!

    Broader source: Energy.gov [DOE]

    Free online courses are now available through the DOE Virtual University (DVU) website on the new DVU Learning Channel

  10. Algorithms for Space-Time Equalization of Wireless Channels

    E-Print Network [OSTI]

    Kouroupetroglou, Georgios

    . In this thesis we investigate receiver techniques for maximum likelihood (ML) joint channel/data estimation for block fading channels, demon- strating the data efficiency provided by the semi-blind approach. The case-channel interference (CCI). In the second part of the thesis we propose two new adaptive equalizers for direct sequence

  11. MISO Broadcast Channels with Confidential Messages and Alternating CSIT

    E-Print Network [OSTI]

    Ulukus, Sennur

    MISO Broadcast Channels with Confidential Messages and Alternating CSIT Pritam Mukherjee1 , Ravi, Blacksburg, VA 24061 Abstract--We study the two-user multiple-input single-output (MISO) broadcast channel-user multiple- input single-output (MISO) broadcast channel with confiden- tial messages (BCCM), in which

  12. Optimizing Feedback in Energy Harvesting MISO Communication Channels

    E-Print Network [OSTI]

    Gesbert, David

    Optimizing Feedback in Energy Harvesting MISO Communication Channels Rajeev Gangula1 , David.gunduz@imperial.ac.uk Abstract--In this work,1 we consider the optimization of feedback in a point-to-point MISO channel in the context of a simple multiple antenna system, namely MISO channel, where feedback can be used to improve

  13. Coordinating a Constrained Channel with Linear Wholesale Price Contracts.

    E-Print Network [OSTI]

    Tsitsiklis, John

    Coordinating a Constrained Channel with Linear Wholesale Price Contracts. Navid Sabbaghi, Yossi, there is a set of linear wholesale price contracts that coordinates the channel while allowing the supplier-supplier/one-newsvendor channel configuration (with each supplier selling a unique product). We analyze how this set of wholesale

  14. Kalman Predictions for Multipoint OFDM Downlink Channels Rikke Apelfrjd

    E-Print Network [OSTI]

    Kalman Predictions for Multipoint OFDM Downlink Channels Rikke Apelfröjd Signals and Systems, Dept for coherent joint transmission. Kalman predictors have the potential to counteract this. This report includes: · Kalman filter equations for multipoint OFDM FDD downlink channels based on results for MIMO OFDM channels

  15. UNCORRECTEDPROOF Effect of channel bifurcation on residual estuarine circulation

    E-Print Network [OSTI]

    Voulgaris, George

    western channel. This is the result of the fact that the magnitude of residual flow scales with the water throughout the water column of the channel while in the adjacent shoals the residual flow is directedUNCORRECTEDPROOF Effect of channel bifurcation on residual estuarine circulation: Winyah Bay, South

  16. Microwave Radiometer – 3 Channel (MWR3C) Handbook

    SciTech Connect (OSTI)

    Cadeddu, MP

    2012-05-04T23:59:59.000Z

    The microwave radiometer 3-channel (MWR3C) provides time-series measurements of brightness temperatures from three channels centered at 23.834, 30, and 89 GHz. These three channels are sensitive to the presence of liquid water and precipitable water vapor.

  17. Concurrent signal combining and channel estimation in digital communications

    DOE Patents [OSTI]

    Ormesher, Richard C. (Albuquerque, NM); Mason, John J. (Albuquerque, NM)

    2011-08-30T23:59:59.000Z

    In the reception of digital information transmitted on a communication channel, a characteristic exhibited by the communication channel during transmission of the digital information is estimated based on a communication signal that represents the digital information and has been received via the communication channel. Concurrently with the estimating, the communication signal is used to decide what digital information was transmitted.

  18. Brief Communication Channel Noise is Essential for Perithreshold Oscillations in

    E-Print Network [OSTI]

    Dorval II, Alan D. "Chuck"

    Brief Communication Channel Noise is Essential for Perithreshold Oscillations in Entorhinal by the stochastic flicker of voltage-gated ion channels, can be a major contributor to electrical membrane noise of persistent Na channels is necessary for the existence of slow perithreshold oscillations that characterize

  19. Analysis of complete positivity conditions for quantum qutrit channels

    E-Print Network [OSTI]

    A. Checinska; K. Wodkiewicz

    2008-12-15T23:59:59.000Z

    We present an analysis of complete positivity (CP) constraints on qutrit quantum channels that have a form of affine transformations of generalized Bloch vector. For diagonal (damping) channels we derive conditions analogous to the ones that in qubit case produce tetrahedron structure in the channel parameter space.

  20. Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint

    E-Print Network [OSTI]

    Greenberg, Albert

    Renewable Energy Scheduling for Fading Channels with Maximum Power Constraint Zhe Wang Electrical--In this paper, we develop efficient algorithm to obtain the optimal energy schedule for fading channel with energy harvesting. We assume that the side information of both the channel states and energy harvesting

  1. An Information Theoretic Analysis on Indoor PLC Channel Characterizations

    E-Print Network [OSTI]

    Gesbert, David

    An Information Theoretic Analysis on Indoor PLC Channel Characterizations Hao LIN , Aawatif MENOUNI. But the development of Power Line Communications (PLC) highly depends on the knowledge of the channel characterizations. For this reason, a large number of attentions have been payed on the PLC channel analysis using

  2. Joint Source-Channel Coding via Turbo Codes

    E-Print Network [OSTI]

    Alajaji, Fady

    Joint Source-Channel Coding via Turbo Codes by Guang-Chong Zhu A dissertation submitted coding. One of the most exciting break- throughs in channel coding is the invention of Turbo codes, whose- tigate three joint source-channel coding issues in the context of Turbo codes. In the #12;rst part

  3. Modeling of multipath fading channels for network simulation

    E-Print Network [OSTI]

    Rajkumar Samuel,

    2009-05-15T23:59:59.000Z

    on the higher layers of the network. Setting up the models is especially difficult for a frequency selective channel. In this thesis the use of non-linear functions to convert the frequency selective channel to an equivalent flat fading channel is examined...

  4. Outage Capacity and Code Design for Dying Channels

    E-Print Network [OSTI]

    Zeng, Meng

    2012-10-19T23:59:59.000Z

    , it is critical to quantify how fast and reliably the information can be collected over attacked links. For a single point-to-point channel subject to a random attack, named as a dying channel, we model it as a block-fading (BF) channel with a finite and random...

  5. Study of Higgs boson production in bosonic decay channels at the LHC (including off-shell production)

    E-Print Network [OSTI]

    Oda, Susumu; The ATLAS collaboration

    2015-01-01T23:59:59.000Z

    The experimental study of Higgs boson production in bosonic decay channels at the LHC will be presented in this presentation. The bosonic decay channels include $ZZ$, $WW$, $\\gamma\\gamma$ and $Z\\gamma$. $WW$ decay channel has a large branching fraction. $\\gamma\\gamma$ and $ZZ$ can construct the whole event topology. $Z\\gamma$ can be sensitive to exotic Higgs decays. Also, off-shell production is now expected to be sensitive to the Higgs decay width and additional Higgs bosons or new phenomena beyond the Standard Model (SM) of the particle physics. Therefore, the bosonic decay channels are assumed to a key to probe the SM and beyond that. This presentation will show the results at $\\sqrt{s}=7$ and $8$ TeV.

  6. On Quantum Channel Estimation with Minimal Resources

    E-Print Network [OSTI]

    M. Zorzi; F. Ticozzi; A. Ferrante

    2011-06-10T23:59:59.000Z

    We determine the minimal experimental resources that ensure a unique solution in the estimation of trace-preserving quantum channels with both direct and convex optimization methods. A convenient parametrization of the constrained set is used to develop a globally converging Newton-type algorithm that ensures a physically admissible solution to the problem. Numerical simulations are provided to support the results, and indicate that the minimal experimental setting is sufficient to guarantee good estimates.

  7. Computational optimization of synthetic water channels.

    SciTech Connect (OSTI)

    Rogers, David Michael; Rempe, Susan L. B.

    2012-12-01T23:59:59.000Z

    Membranes for liquid and gas separations and ion transport are critical to water purification, osmotic energy generation, fuel cells, batteries, supercapacitors, and catalysis. Often these membranes lack pore uniformity and robustness under operating conditions, which can lead to a decrease in performance. The lack of uniformity means that many pores are non-functional. Traditional membranes overcome these limitations by using thick membrane materials that impede transport and selectivity, which results in decreased performance and increased operating costs. For example, limitations in membrane performance demand high applied pressures to deionize water using reverse osmosis. In contrast, cellular membranes combine high flux and selective transport using membrane-bound protein channels operating at small pressure differences. Pore size and chemistry in the cellular channels is defined uniformly and with sub-nanometer precision through protein folding. The thickness of these cellular membranes is limited to that of the cellular membrane bilayer, about 4 nm thick, which enhances transport. Pores in the cellular membranes are robust under operating conditions in the body. Recent efforts to mimic cellular water channels for efficient water deionization produced a significant advance in membrane function. The novel biomimetic design achieved a 10-fold increase in membrane permeability to water flow compared to commercial membranes and still maintained high salt rejection. Despite this success, there is a lack of understanding about why this membrane performs so well. To address this lack of knowledge, we used highperformance computing to interrogate the structural and chemical environments experienced by water and electrolytes in the newly created biomimetic membranes. We also compared the solvation environments between the biomimetic membrane and cellular water channels. These results will help inform future efforts to optimize and tune the performance of synthetic biomimetic membranes for applications in water purification, energy, and catalysis.

  8. Salinity patterns in the Houston Ship Channel

    E-Print Network [OSTI]

    Withers, Richard Ercelray

    1969-01-01T23:59:59.000Z

    to the highly stratified. It is also subject to heavy industrial waste loading and large volumes of urban storm runoff. Further, the tidal action in ihe channel is relatively minor, The mean tide elevation normally varies from one to two feet. A multiple... linear regression analysis is us d to derive the prediction eouation. The parameters are included in the regression analysis raised to various combinations of powers to expedite a non-linear analysis. The best ? fit predic- tion equation is determined...

  9. Stanford University Exploiting Channel Knowledge at the Tx in MISO and MIMO Wireless Exploiting Partial Channel Knowledge at

    E-Print Network [OSTI]

    Paulraj, Arogyaswami

    Stanford University Exploiting Channel Knowledge at the Tx in MISO and MIMO Wireless Exploiting Partial Channel Knowledge at the Transmitter in MISO and MIMO Wireless SPAWC 2003 Rome, Italy June 18 Exploiting Channel Knowledge at the Tx in MISO and MIMO Wireless Outline Introduction · Perfect CSI

  10. Measurement of the top quark mass in the dilepton channel

    SciTech Connect (OSTI)

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Agelou, M.; Aguilo, E.; Ahn, S.H.; Ahsan, M.; Alexeev, G.D.; /Buenos Aires U. /Rio de Janeiro, CBPF /Rio de Janeiro State U. /Sao Paulo, IFT /Alberta U. /Simon Fraser U. /York U., Canada /McGill U. /Hefei, CUST /Andes U., Bogota /Charles U.

    2006-09-01T23:59:59.000Z

    We present a measurement of the top quark mass in the dilepton channel based on approximately 370 pb{sup -1} of data collected by the D0 experiment during Run II of the Fermilab Tevatron collider. We employ two different methods to extract the top quark mass. We show that both methods yield consistent results using ensemble tests of events generated with the D0 Monte Carlo simulation. We combine the results from the two methods to obtain a top quark mass m{sub t} = 178.1 {+-} 8.2 GeV. The statistical uncertainty is 6.7 GeV and the systematic uncertainty is 4.8 GeV.

  11. Collective response of self-organised clusters of mechanosensitive channels

    E-Print Network [OSTI]

    Ksenia Guseva; Marco Thiel; Ian Booth; Samantha Miller; Celso Grebogi; Alessandro de Moura

    2011-01-02T23:59:59.000Z

    Mechanosensitive channels are ion channels activated by membrane tension. We investigate the influence of bacterial mechanosensitive channels spatial distribution on activation (gating). Based on elastic short-range interactions we map this physical process onto an Ising-like model, which enables us to predict the clustering of channels and the effects of clustering on their gating. We conclude that the aggregation of channels and the consequent interactions among them leads to a global cooperative gating behaviour with potentially dramatic consequences for the cell.

  12. Energy conversion device with support member having pore channels

    DOE Patents [OSTI]

    Routkevitch, Dmitri [Longmont, CO; Wind, Rikard A [Johnstown, CO

    2014-01-07T23:59:59.000Z

    Energy devices such as energy conversion devices and energy storage devices and methods for the manufacture of such devices. The devices include a support member having an array of pore channels having a small average pore channel diameter and having a pore channel length. Material layers that may include energy conversion materials and conductive materials are coaxially disposed within the pore channels to form material rods having a relatively small cross-section and a relatively long length. By varying the structure of the materials in the pore channels, various energy devices can be fabricated, such as photovoltaic (PV) devices, radiation detectors, capacitors, batteries and the like.

  13. Optimal channel allocation with dynamic power control in cellular networks

    E-Print Network [OSTI]

    Wu, Xin; Bari, Ataul; 10.5121/ijcnc.2011.3206

    2011-01-01T23:59:59.000Z

    Techniques for channel allocation in cellular networks have been an area of intense research interest for many years. An efficient channel allocation scheme can significantly reduce call-blocking and calldropping probabilities. Another important issue is to effectively manage the power requirements for communication. An efficient power control strategy leads to reduced power consumption and improved signal quality. In this paper, we present a novel integer linear program (ILP) formulation that jointly optimizes channel allocation and power control for incoming calls, based on the carrier-to-interference ratio (CIR). In our approach we use a hybrid channel assignment scheme, where an incoming call is admitted only if a suitable channel is found such that the CIR of all ongoing calls on that channel, as well as that of the new call, will be above a specified value. Our formulation also guarantees that the overall power requirement for the selected channel will be minimized as much as possible and that no ongoin...

  14. IEEE COMMUNICATIONS LETTERS, VOL. 6, NO. 11, NOVEMBER 2002 503 Channel Reliability Estimation for Turbo Decoding

    E-Print Network [OSTI]

    Lee, Jae Hong

    for Turbo Decoding in Rayleigh Fading Channels With Imperfect Channel Estimates Hyundong Shin, Student scheme of the channel reliability factor for turbo decoding in Rayleigh fading channels with imperfect channel estimates. The channel re- liability factor is required for iterative MAP decoding of turbo codes

  15. CSM Trailhead Channel Development Policy page 1 of 1 Colorado School of Mines Trailhead

    E-Print Network [OSTI]

    . Channel Development III. Channel Development Work Flow IV. Channel Building Tools V. Channel Requirements VI. Channel Guidelines VII. Responsibilities of Users VIII. Related Links Appendix A. Tab. Channels are intended to deliver dynamic, high-demand content and interactive applications to a significant

  16. Contribution of potassium channels to myogenic response in skeletal muscle arterioles: effects of age and fiber type

    E-Print Network [OSTI]

    Kim, Se Jeong

    2006-10-30T23:59:59.000Z

    channels and voltage-dependent (Kv) potassium channels; these channels have a role in the negativefeedback pathways that modulate depolarization and myogenic constriction. We tested the hypothesis that increased KCa channel and Kv channel activity...

  17. Optimal Distributed Beamforming for MISO Interference Channels

    E-Print Network [OSTI]

    Qiu, Jiaming; Luo, Zhi-Quan; Cui, Shuguang

    2010-01-01T23:59:59.000Z

    We consider the problem of quantifying the Pareto optimal boundary in the achievable rate region over multiple-input single-output (MISO) interference channels, where the problem boils down to solving a sequence of convex feasibility problems after certain transformations. The feasibility problem is solved by two new distributed optimal beamforming algorithms, where the first one is to parallelize the computation based on the method of alternating projections, and the second one is to localize the computation based on the method of cyclic projections. Convergence proofs are established for both algorithms.

  18. Flow in channels with superhydrophobic trapezoidal textures

    E-Print Network [OSTI]

    Nizkaya, Tatiana V; Vinogradova, Olga I

    2013-01-01T23:59:59.000Z

    Superhydrophobic one-dimensional surfaces reduce drag and generate transverse hydrodynamic phenomena by combining hydrophobicity and roughness to trap gas bubbles in a microscopic textures. Recent work in this area has focused on specific cases of superhydrophobic stripes. Here we study theoretically and numerically the hydrodynamic flow in a channel with a superhydrophobic trapezoidal texture. These allow us to evaluate the drag reduction and anisotropy of the flow for various trapezoidal reliefs. Our results provide a framework for the rational design of superhydrophobic surfaces for microfluidic applications.

  19. Carderock Circulating Water Channel | Open Energy Information

    Open Energy Info (EERE)

    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 You are being directedAnnualProperty EditCalifornia:Power LPInformation 8thCalwind IICaneyNW1Circulating Water Channel

  20. A seismic approach to testing different formation channels of subdwarf B stars

    E-Print Network [OSTI]

    Haili Hu; M. -A. Dupret; C. Aerts; G. Nelemans; S. D. Kawaler; A. Miglio; J. Montalban; R. Scuflaire

    2008-08-22T23:59:59.000Z

    There are many unknowns in the formation of subdwarf B stars. Different formation channels are considered to be possible and to lead to a variety of helium-burning subdwarfs. All seismic models to date, however, assume that a subdwarf B star is a post-helium-flash-core surrounded by a thin inert layer of hydrogen. We examine an alternative formation channel, in which the subdwarf B star originates from a massive (>~2 Msun) red giant with a non-degenerate helium-core. Although these subdwarfs may evolve through the same region of the log g-Teff diagram as the canonical post-flash subdwarfs, their interior structure is rather different. We examine how this difference affects their pulsation modes and whether it can be observed. Using detailed stellar evolution calculations we construct subdwarf B models from both formation channels. The iron accumulation in the driving region due to diffusion, which causes the excitation of the modes, is approximated by a Gaussian function. The pulsation modes and frequencies are calculated with a non-adiabatic pulsation code. A detailed comparison of two subdwarf B models from different channels, but with the same log g and Teff, shows that their mode excitation is different. The excited frequencies are lower for the post-flash than for the post-non-degenerate subdwarf B star. This is mainly due to the differing chemical composition of the stellar envelope. A more general comparison between two grids of models shows that the excited frequencies of most post-non-degenerate subdwarfs cannot be well-matched with the frequencies of post-flash subdwarfs. In the rare event that an acceptable seismic match is found, additional information, such as mode identification and log g and Teff determinations, allows us to distinguish between the two formation channels.

  1. Robust Secure Transmission in MISO Channels Based on Worst-Case Optimization

    E-Print Network [OSTI]

    Huang, Jing

    2011-01-01T23:59:59.000Z

    This paper studies robust transmission schemes for multiple-input single-output (MISO) wiretap channels. Both the cases of direct transmission and cooperative jamming with a helper are investigated with imperfect channel state information (CSI) for the eavesdropper links. Robust transmit covariance matrices are obtained based on worst-case secrecy rate maximization, under both individual and global power constraints. For the case of an individual power constraint, we show that the non-convex maximin optimization problem can be transformed into a quasiconvex problem that can be efficiently solved with existing methods. For a global power constraint, the joint optimization of the transmit covariance matrices and power allocation between the source and the helper is studied via geometric programming. We also study the robust wiretap transmission problem for the case with a quality-of-service constraint at the legitimate receiver. Numerical results show the advantage of the proposed robust design. In particular, ...

  2. SUBMITTED TO IEEE TRANS. ON INFORM. THEORY 1 Source-Channel Diversity for Parallel Channels

    E-Print Network [OSTI]

    Martinian, Emin

    is with the Department of Electrical Engineering, University of Notre Dame, Notre Dame, IN 46556. Email: jnl@nd.edu Emin Martinian and Gregory Wornell are with the Department of Electrical Engineering and Computer Science constraints of the desired application, such channel fluctuations cause outages. Specifically, when

  3. Local heat/mass transfer distributions around sharp 180 deg turns in two-pass smooth and rib-roughened channels

    SciTech Connect (OSTI)

    Han, J.C.; Chandra, P.R.; Lau, S.C. (Texas A and M Univ., College Station (United States))

    1988-02-01T23:59:59.000Z

    The detailed mass transfer distributions around the sharp 180 deg turns in a two-pass, square, smooth channel and in an identical channel with two rib-roughened opposite walls were determined via the napthalene sublimation technique. The top, bottom, inner (divider), and outer walls of the test channel were napthalene-coated surfaces. For the ribbed channel tests, square, transverse, brass ribs were attached to the top and bottom walls of the channel in alignment. The rib height-to-hydraulic diameter ratios (e/D) were 0.063 and 0.094; the rib pitch-to-height ratios (P/e) were 10 and 20. Experiments were conducted for three Reynolds numbers of 15,000, 30,000 and 60,000. Results show that the Sherwood numbers on the top, outer, and inner walls around the turn in the rib-roughened channel are higher than the corresponding Sherwood numbers around the turn in the smooth channel. For both the smooth and the ribbed channels, the Sherwood numbers after the sharp turn are higher than those before the turn. The regional averages of the local Sherwood numbers are correlated and compared with published heat transfer data.

  4. Calibration of a 32 channel electron cyclotron emission radiometer on the HL-2A tokamak

    SciTech Connect (OSTI)

    Shi, Z. B., E-mail: shizb@swip.ac.cn; Jiang, M.; Huang, X. L.; Zhong, W. L.; Chen, W.; Che, Y. L.; Liu, Z. T.; Ding, X. T.; Yang, Q. W.; Duan, X. R. [Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, P. O. Box 432, Chengdu 610041 (China)

    2014-02-15T23:59:59.000Z

    A novel 32-channel electron cyclotron emission radiometer has been designed and tested for the measurement of electron temperature profiles on the HL-2A tokamak. This system is based on the intermediate frequency filter detection technique, and has the features of wide working frequency range and high spatial resolution. Two relative calibration methods have been investigated: sweeping the toroidal magnetic field and hopping the output frequency of the local oscillator. Preliminary results show that both methods can ensure reasonable profiles.

  5. Magnets for Muon 6D Cooling Channels

    SciTech Connect (OSTI)

    Johnson, Rolland [Muons, Inc.; Flanagan, Gene [Muons, Inc.

    2014-09-10T23:59:59.000Z

    The Helical Cooling Channel (HCC), an innovative technique for six-dimensional (6D) cooling of muon beams using a continuous absorber inside superconducting magnets, has shown considerable promise based on analytic and simulation studies. The implementation of this revolutionary method of muon cooling requires high field superconducting magnets that provide superimposed solenoid, helical dipole, and helical quadrupole fields. Novel magnet design concepts are required to provide HCC magnet systems with the desired fields for 6D muon beam cooling. New designs feature simple coil configurations that produce these complex fields with the required characteristics, where new high field conductor materials are particularly advantageous. The object of the program was to develop designs and construction methods for HCC magnets and design a magnet system for a 6D muon beam cooling channel. If successful the program would develop the magnet technologies needed to create bright muon beams for many applications ranging from scientific accelerators and storage rings to beams to study material properties and new sources of energy. Examples of these applications include energy frontier muon colliders, Higgs and neutrino factories, stopping muon beams for studies of rare fundamental interactions and muon catalyzed fusion, and muon sources for cargo screening for homeland security.

  6. apical water channels: Topics by E-print Network

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

    that ?etwee 322 THE EFFECT OF CHANNELIZATION ON FLOODPLAIN SEDIMENT DEPOSITION AND SUBSIDENCE ALONG THE POCOMOKE RIVER, MARYLAND1 Multidisciplinary Databases and Resources...

  7. aquaporin-2 water channel: Topics by E-print Network

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

    that ?etwee 275 THE EFFECT OF CHANNELIZATION ON FLOODPLAIN SEDIMENT DEPOSITION AND SUBSIDENCE ALONG THE POCOMOKE RIVER, MARYLAND1 Multidisciplinary Databases and Resources...

  8. aquaporin-2 water channels: Topics by E-print Network

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

    that ?etwee 275 THE EFFECT OF CHANNELIZATION ON FLOODPLAIN SEDIMENT DEPOSITION AND SUBSIDENCE ALONG THE POCOMOKE RIVER, MARYLAND1 Multidisciplinary Databases and Resources...

  9. aqp1 water channel: Topics by E-print Network

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

    that ?etwee 285 THE EFFECT OF CHANNELIZATION ON FLOODPLAIN SEDIMENT DEPOSITION AND SUBSIDENCE ALONG THE POCOMOKE RIVER, MARYLAND1 Multidisciplinary Databases and Resources...

  10. aquaporin-1 water channels: Topics by E-print Network

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

    that ?etwee 284 THE EFFECT OF CHANNELIZATION ON FLOODPLAIN SEDIMENT DEPOSITION AND SUBSIDENCE ALONG THE POCOMOKE RIVER, MARYLAND1 Multidisciplinary Databases and Resources...

  11. Coupled-channel scattering in 1 + 1 dimensional lattice model

    SciTech Connect (OSTI)

    Guo, Peng [JLAB

    2013-07-01T23:59:59.000Z

    Based on the Lippmann-Schwinger equation approach, a generalized Lüscher’s formula in 1+1 dimensions for two particles scattering in both the elastic and coupled-channel cases in moving frames is derived. A two-dimensional coupled-channel scattering lattice model is presented, which represents a two-coupled-channel resonant scattering scalars system. The Monte Carlo simulation is performed on finite lattices and in various moving frames. The two-dimensional generalized Lüscher’s formula is used to extract the scattering amplitudes for the coupled-channel system from the discrete finite-volume spectrum.

  12. Hydrology, environment Four remarks on the growth of channel networks

    E-Print Network [OSTI]

    Kudrolli, Arshad

    Hydrology, environment Four remarks on the growth of channel networks Quatre remarques sur la online xxx Presented by Ghislain de Marsily Keywords: Geomorphology Hydrology River network Mots cle

  13. Quantum state discrimination with bosonic channels and Gaussian states

    E-Print Network [OSTI]

    Tan, Si Hui, Ph. D. Massachusetts Institute of Technology

    2010-01-01T23:59:59.000Z

    Discriminating between quantum states is an indispensable part of quantum information theory. This thesis investigates state discrimination of continuous quantum variables, focusing on bosonic communication channels and ...

  14. PEP II 16-channel corrector controller using BITBUS

    SciTech Connect (OSTI)

    Olsen, R.

    1997-07-01T23:59:59.000Z

    A 16-channel controller has been implemented to control the PEP II corrector switching power converters. The design and performance are discussed.

  15. Proton Channel Orientation in Block-Copolymer Electrolyte Membranes

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

    Proton Channel Orientation in Block-Copolymer Electrolyte Membranes Print Fuel cells have the potential to provide power for a wide variety of applications ranging from electronic...

  16. Experimental characterization of Gaussian quantum-communication channels

    SciTech Connect (OSTI)

    Di Guglielmo, James; Hage, Boris; Franzen, Alexander; Schnabel, Roman [Institut fuer Gravitationsphysik, Leibniz Universitaet Hannover and Max-Planck-Institut fuer Gravitationsphysik (Albert-Einstein-Institute), Callinstrasse 38, 30167 Hannover (Germany); Fiurasek, Jaromir [Department of Optics, Palacky University, 17 listopadu 50, 77200 Olomouc (Czech Republic)

    2007-07-15T23:59:59.000Z

    We present a full experimental characterization of continuous-variable quantum-communication channels established by shared entanglement together with local operations and classical communication. The resulting teleportation channel was fully characterized by measuring all elements of the covariance matrix of the shared two-mode squeezed Gaussian state. From the experimental data we determined the lower bound to the quantum channel capacity, the teleportation fidelity of coherent states, and the logarithmic negativity and purity of the shared state. Additionally, a positive secret key rate was obtained for two of the established channels.

  17. Progress on Superconducting Magnets for the MICE Cooling Channel

    E-Print Network [OSTI]

    Green, Michael A

    2010-01-01T23:59:59.000Z

    274 Progress on the Superconducting Magnets for the MICEM. A Green and J. M. Rey, “Superconducting Solenoids for anG, “Supercritically Cooled Superconducting Muon Channel,”

  18. The Effect of the Treatment of Localised Friction in Two-Phase Mixtures on the Stability of Parallel Channels

    SciTech Connect (OSTI)

    Abdou, H.N.; Garea, V.B. [Instituto Balseiro and Centro Atomico Bariloche, CNEA, Av. Bustillo 9500, Bariloche, RN 8400 (Argentina); Larreteguy, A.E. [Universidad Argentina de la Empresa, Lima 717, 1073 Buenos Aires (Argentina)

    2002-07-01T23:59:59.000Z

    A one-dimensional analytical model has been developed to be used for the linear analysis of density-wave oscillations in a parallel heated channel. The heated channel is divided into a single-phase and a two-phase region. The two-phase region is represented by the homogeneous model. The localised friction at the channel exit is treated considering the two-phase mixture. The exact equation for the total channel pressure drop is perturbed around the steady state. The stability characteristics of the heated channel are investigated using the Nyquist criterion. The marginal stability boundary (MSB) is determined in the two-dimensional thermodynamic equilibrium space parameters, the subcooled boiling number and the phase change number. The predictions of the model are compared with experimental results published in open literature. The results indicate a more stable system with (1) low system pressure, (2) high inlet restriction, (3) low outlet restriction, and (4) high inlet velocity. The results show that the model agrees well with the available experimental data. In particular, the results show the significance of correcting the localised friction due to the presence of the two-phase mixture in the two-phase region: explicit inclusion of the two-phase localised friction improves the agreement with experimental results. This effect is more important for high heating power and high inlet subcooling. (authors)

  19. Stable stationary vortices and traveling oscillatory vortices in a stenotic fluid-flow channel David W. Pravica,1

    E-Print Network [OSTI]

    Bier, Martin

    will show that a sufficiently large boundary vor- ticity layer is required for stationary vortices and that a suf- ficiently high Reynolds number with a boundary shear stress is required for traveling oscillatoryStable stationary vortices and traveling oscillatory vortices in a stenotic fluid-flow channel

  20. Electron-conformational transformations in nanoscopic RyR channels govern both the heart's contraction and beating

    E-Print Network [OSTI]

    A. S. Moskvin; A. M. Ryvkin; O. E. Solovyova; V. S. Markhasin

    2011-03-31T23:59:59.000Z

    We show that a simple biophysically based electron-conformational model of RyR channel is able to explain and describe on equal footing the oscillatory regime of the heart's cell release unit both in sinoatrial node (pacemaker) cells under normal physiological conditions and in ventricular myocytes under Ca$^{2+}$ SR overload.

  1. Abrupt termination of a quantum channel and exactly solvable position-dependent mass models in three dimensions

    E-Print Network [OSTI]

    C. Quesne

    2007-03-04T23:59:59.000Z

    We consider a particle with a position-dependent mass, moving in a three-dimensional semi-infinite parallelepipedal or cylindrical channel under the influence of some hyperbolic potential. We show that the lack of uniformity in the environment generates an infinite number of bound states.

  2. Entropy of quantum channel in the theory of quantum information

    E-Print Network [OSTI]

    Wojciech Roga

    2011-10-03T23:59:59.000Z

    Quantum channels, also called quantum operations, are linear, trace preserving and completely positive transformations in the space of quantum states. Such operations describe discrete time evolution of an open quantum system interacting with an environment. The thesis contains an analysis of properties of quantum channels and different entropies used to quantify the decoherence introduced into the system by a given operation. Part I of the thesis provides a general introduction to the subject. In Part II, the action of a quantum channel is treated as a process of preparation of a quantum ensemble. The Holevo information associated with this ensemble is shown to be bounded by the entropy exchanged during the preparation process between the initial state and the environment. A relation between the Holevo information and the entropy of an auxiliary matrix consisting of square root fidelities between the elements of the ensemble is proved in some special cases. Weaker bounds on the Holevo information are also established. The entropy of a channel, also called the map entropy, is defined as the entropy of the state corresponding to the channel by the Jamiolkowski isomorphism. In Part III of the thesis, the additivity of the entropy of a channel is proved. The minimal output entropy, which is difficult to compute, is estimated by an entropy of a channel which is much easier to obtain. A class of quantum channels is specified, for which additivity of channel capacity is conjectured. The last part of the thesis contains characterization of Davies channels, which correspond to an interaction of a state with a thermal reservoir in the week coupling limit, under the condition of quantum detailed balance and independence of rotational and dissipative evolutions. The Davies channels are characterized for one-qubit and one-qutrit systems.

  3. Helical Muon Beam Cooling Channel Engineering Design

    SciTech Connect (OSTI)

    Kashikhin, V.S.; Lopes, M.L.; Romanov, G.V.; Tartaglia, M.A.; Yonehara, K.; Yu, M.; Zlobin, A.V.; /Fermilab; Flanagan, G.; Johnson, R.P.; Kazakevich, G.M.; Marhauser, F.; /MUONS Inc., Batavia

    2012-05-01T23:59:59.000Z

    The Helical Cooling Channel (HCC), a novel technique for six-dimensional (6D) ionization cooling of muon beams, has shown considerable promise based on analytic and simulation studies. However, the implementation of this revolutionary method of muon cooling requires new techniques for the integration of hydrogen-pressurized, high-power RF cavities into the low-temperature superconducting magnets of the HCC. We present the progress toward a conceptual design for the integration of 805 MHz RF cavities into a 10 T Nb{sub 3}Sn based HCC test section. We include discussions on the pressure and thermal barriers needed within the cryostat to maintain operation of the magnet at 4.2 K while operating the RF and energy absorber at a higher temperature. Additionally, we include progress on the Nb{sub 3}Sn helical solenoid design.

  4. Power module assemblies with staggered coolant channels

    DOE Patents [OSTI]

    Herron, Nicholas Hayden; Mann, Brooks S; Korich, Mark D

    2013-07-16T23:59:59.000Z

    A manifold is provided for supporting a power module assembly with a plurality of power modules. The manifold includes a first manifold section. The first face of the first manifold section is configured to receive the first power module, and the second face of the first manifold section defines a first cavity with a first baseplate thermally coupled to the first power module. The first face of the second manifold section is configured to receive the second power module, and the second face of the second manifold section defines a second cavity with a second baseplate thermally coupled to the second power module. The second face of the first manifold section and the second face of the second manifold section are coupled together such that the first cavity and the second cavity form a coolant channel. The first cavity is at least partially staggered with respect to second cavity.

  5. Multiple channel optical data acquisition system

    DOE Patents [OSTI]

    Fasching, G.E.; Goff, D.R.

    1985-02-22T23:59:59.000Z

    A multiple channel optical data acquisition system is provided in which a plurality of remote sensors monitoring specific process variable are interrogated by means of a single optical fiber connecting the remote station/sensors to a base station. The remote station/sensors derive all power from light transmitted through the fiber from the base station. Each station/sensor is individually accessed by means of a light modulated address code sent over the fiber. The remote station/sensors use a single light emitting diode to both send and receive light signals to communicate with the base station and provide power for the remote station. The system described can power at least 100 remote station/sensors over an optical fiber one mile in length.

  6. Di-Higgs phenomenology: The forgotten channel

    E-Print Network [OSTI]

    Christoph Englert; Frank Krauss; Michael Spannowsky; Jennifer Thompson

    2014-09-29T23:59:59.000Z

    Searches for multi-Higgs final states allow to constrain parameters of the SM (or extensions thereof) that directly relate to the mechanism of electroweak symmetry breaking. Multi-Higgs production cross sections, however, are small and the phenomenologically accessible final states are challenging to isolate in the busy multi-jet hadron collider environment of the LHC run 2. This makes the necessity to extend the list of potentially observable production mechanisms obvious. Most of the phenomenological analyses in the past have focused on $gg\\to hh+jets$; in this paper we study $pp\\to t\\bar t hh$ at LHC run 2 and find that this channel for $h\\to b\\bar b$ and semi-leptonic and hadronic top decays has the potential to provide an additional handle to constrain the Higgs trilinear coupling in a global fit at the end of run 2.

  7. Multi-channel medical imaging system

    DOE Patents [OSTI]

    Frangioni, John V

    2013-12-31T23:59:59.000Z

    A medical imaging system provides simultaneous rendering of visible light and fluorescent images. The system may employ dyes in a small-molecule form that remain in the subject's blood stream for several minutes, allowing real-time imaging of the subject's circulatory system superimposed upon a conventional, visible light image of the subject. The system may provide an excitation light source to excite the fluorescent substance and a visible light source for general illumination within the same optical guide used to capture images. The system may be configured for use in open surgical procedures by providing an operating area that is closed to ambient light. The systems described herein provide two or more diagnostic imaging channels for capture of multiple, concurrent diagnostic images and may be used where a visible light image may be usefully supplemented by two or more images that are independently marked for functional interest.

  8. New York Event to Show Bi-Partisan, International Support for...

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

    New York Event to Show Bi-Partisan, International Support for Geothermal Energy in America New York Event to Show Bi-Partisan, International Support for Geothermal Energy in...

  9. Effective charge and free energy of DNA inside an ion channel

    E-Print Network [OSTI]

    Jingshan Zhang; B. I. Shklovskii

    2008-03-03T23:59:59.000Z

    Translocation of a single stranded DNA (ssDNA) through an alpha-hemolysin channel in a lipid membrane driven by applied transmembrane voltage V was extensively studied recently. While the bare charge of the ssDNA piece inside the channel is approximately 12 (in units of electron charge) measurements of different effective charges resulted in values between one and two. We explain these challenging observations by a large self-energy of a charge in the narrow water filled gap between ssDNA and channel walls, related to large difference between dielectric constants of water and lipid, and calculate effective charges of ssDNA. We start from the most fundamental stall charge $q_s$, which determines the force $F_s= q_s V/L$ stalling DNA against the voltage V (L is the length of the channel). We show that the stall charge $q_s$ is proportional to the ion current blocked by DNA, which is small due to the self-energy barrier. Large voltage V reduces the capture barrier which DNA molecule should overcome in order to enter the channel by $|q_c|V$, where $q_c$ is the effective capture charge. We expressed it through the stall charge $q_s$. We also relate the stall charge $q_s$ to two other effective charges measured for ssDNA with a hairpin in the back end: the charge $q_u$ responsible for reduction of the barrier for unzipping of the hairpin and the charge $q_e$ responsible for DNA escape in the direction of hairpin against the voltage. At small V we explain reduction of the capture barrier with the salt concentration.

  10. Additivity of the Renyi entropy of order 2 for positive-partial-transpose-inducing channels

    E-Print Network [OSTI]

    B. Dierckx; M. Fannes; C. Vandenplas

    2008-06-02T23:59:59.000Z

    We prove that the minimal Renyi entropy of order 2 (RE2) output of a positive-partial-transpose(PPT)-inducing channel joint to an arbitrary other channel is equal to the sum of the minimal RE2 output of the individual channels. PPT-inducing channels are channels with a Choi matrix which is bound entangled or separable. The techniques used can be easily recycled to prove additivity for some non-PPT-inducing channels such as the depolarizing and transpose depolarizing channels, though not all known additive channels. We explicitly make the calculations for generalized Werner-Holevo channels as an example of both the scope and limitations of our techniques.

  11. Prediction of Channel Thermal Noise in Twin Silicon Nanowire MOSFET (TSNWFET)

    E-Print Network [OSTI]

    Lee, Jong Duk

    proportional to the drain driving current. 3. Derivation of channel thermal noise For analyzing channel thermal effects, the power spectral density equation of channel thermal noise suitable for short channelPrediction of Channel Thermal Noise in Twin Silicon Nanowire MOSFET (TSNWFET) Jaehong Lee, Jongwook

  12. On Sufficient Conditions for Testing Optimality of Codewords in ISI Channels

    E-Print Network [OSTI]

    Kavcic, Aleksandar

    On Sufficient Conditions for Testing Optimality of Codewords in ISI Channels Fabian Lim1 if a codeword is optimal, for intersymbol interference (ISI) channels. I. INTRODUCTION The maximum interference (ISI) channels, where (channel) memory is present. The techniques for the memoryless channels

  13. Optimal Training Signals for MIMO OFDM Channel Estimation

    E-Print Network [OSTI]

    Minn, Hlaing

    Optimal Training Signals for MIMO OFDM Channel Estimation Hlaing Minn*, Member, IEEE and Naofal Al.minn@utdallas.edu, aldhahir@utdallas.edu Abstract--This paper presents general classes of optimal train- ing signals transform are used to derive the optimal training signals which minimize the channel estimation mean square

  14. Blind channel identification and extraction of more sources than sensors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Blind channel identification and extraction of more sources than sensors P. Comonba a I3S that a static system with more inputs (sources) than outputs (sensors, or channels) cannot be blindly identified blind identification problem. Here, in order to demonstrate its feasibility, the procedure is detailed

  15. Blind Channel Identification for the Emitter Location Problem

    E-Print Network [OSTI]

    Fowler, Mark

    a thesis entitled "Blind Channel Identification for the Emitter Location Problem: A Least Square ApproachBlind Channel Identification for the Emitter Location Problem: A Least Square Approach BY Cheung C. Chau B.S.E.E., Binghamton University, 2000 Thesis Submitted in Partial Fulfillment of the Requirements

  16. Robust Secure Transmission in MISO Channels With Imperfect ECSI

    E-Print Network [OSTI]

    Swindlehurst, A. Lee

    Robust Secure Transmission in MISO Channels With Imperfect ECSI Jing Huang and A. Lee Swindlehurst.huang; swindle}@uci.edu Abstract--This paper studies robust transmission schemes for MISO wiretap channels-input single-output (MISO) wiretap cannels, the optimal transmit covariance matrix was found to be single

  17. MISO Broadcasting FBMC System for Highly Frequency Selective Channels

    E-Print Network [OSTI]

    Swindlehurst, A. Lee

    MISO Broadcasting FBMC System for Highly Frequency Selective Channels Michael Newinger, Leonardo G.a.nossek}@tum.de swindle@uci.edu Abstract--In this contribution we propose new techniques for multi-user MISO broadcasting an SDMA approach for the MISO broadcast channel based on Tomlinson-Harashima Precoding. However

  18. Columbia River Channel Improvement Project Rock Removal Blasting: Monitoring Plan

    SciTech Connect (OSTI)

    Carlson, Thomas J.; Johnson, Gary E.

    2010-01-29T23:59:59.000Z

    This document provides a monitoring plan to evaluate take as outlined in the National Marine Fisheries Service 2002 Biological Opinion for underwater blasting to remove rock from the navigation channel for the Columbia River Channel Improvement Project. The plan was prepared by the Pacific Northwest National Laboratory (PNNL) for the U.S. Army Corps of Engineers (USACE), Portland District.

  19. New Digital Block Implementation Algorithm for MIMO Channel Hardware Simulator

    E-Print Network [OSTI]

    Boyer, Edmond

    in a controllable and repeatable laboratory environment. After a description of the MIMO channel models], the FPGAs provide the greatest design flexibility and visibility of resource utilization. The channel models electromagnetic waves interact with the propagation environment. Thus, they have to be considered in the design

  20. Contraction scour in compound channels with cohesive soil beds

    E-Print Network [OSTI]

    Israel Devadason, Benjamin Praisy

    2009-05-15T23:59:59.000Z

    .................................................................................4 1.3 Approaches And Methodologies..............................................................5 II BASIC CONCEPTS AND PARAMETERS IN BRIDGE SCOUR .....................8 2.1 Introduction......................................................................................................31 4.5 General Test Arrangement .....................................................................35 V FLUME TESTS ? THE COMPOUND CHANNEL MODEL............................43 5.1 The Compound Channel Model...

  1. Contraction scour in compound channels with cohesive soil beds

    E-Print Network [OSTI]

    Israel Devadason, Benjamin Praisy

    2008-10-10T23:59:59.000Z

    .................................................................................4 1.3 Approaches And Methodologies..............................................................5 II BASIC CONCEPTS AND PARAMETERS IN BRIDGE SCOUR .....................8 2.1 Introduction......................................................................................................31 4.5 General Test Arrangement .....................................................................35 V FLUME TESTS – THE COMPOUND CHANNEL MODEL............................43 5.1 The Compound Channel Model...

  2. Iterative Water-filling for Gaussian Vector Multiple Access Channels

    E-Print Network [OSTI]

    Li, Tiffany Jing

    Iterative Water-filling for Gaussian Vector Multiple Access Channels W. Yu, W. Rhee, S. Boyd, and J. Cioffi Zhenlei Shen Lehigh University March 29, 2005 Zhenlei Shen (Lehigh) Iterative Water-filling for Gaussian Vector Multiple Access ChannelsMarch 29, 2005 1 / 13 #12;1 Quick Review 2 Iterative Water

  3. The Energy Harvesting Multiple Access Channel with Energy Storage Losses

    E-Print Network [OSTI]

    Yener, Aylin

    The Energy Harvesting Multiple Access Channel with Energy Storage Losses Kaya Tutuncuoglu and Aylin considers a Gaussian multiple access channel with two energy harvesting transmitters with lossy energy storage. The power allocation policy maximizing the average weighted sum rate given the energy harvesting

  4. Design and analysis of iteratively decodable codes for ISI channels

    E-Print Network [OSTI]

    Doan, Dung Ngoc

    2005-11-01T23:59:59.000Z

    B from the capacity have been designed in the literature. In this dissertation, we will focus on the design and analysis of near-capacity achieving codes for another important class of channels, namely inter-symbol interference (ISI)channels. We propose...

  5. Analysis of Seepage from Polygon Channels Bhagu R. Chahar1

    E-Print Network [OSTI]

    Chahar, B. R.

    Analysis of Seepage from Polygon Channels Bhagu R. Chahar1 Abstract: An exact analytical solution conformal mapping and Green- Neumann functions. Chahar 2001 analyzed seepage from slit and strip channels by a drainage layer. Chahar 2000 and Swamee et al. 2001 obtained an analytical solution for seepage from

  6. TIME-VARYING CHANNEL MODEL EFFICIENCY Scott Rickard

    E-Print Network [OSTI]

    Drakakis, Konstantinos

    with constant radial velocity relative to one an- other. For ease of presentation, we consider in this work the derivation of the Doppler effect, although the resulting channel for elec- tromagnetic waves has a similar path Doppler effect non- relativistic channel. In Section 3 we derive the continuous time

  7. Subcarrier Clustering for MISO-OFDM Channels with Quantized Beamforming

    E-Print Network [OSTI]

    Santipach, - Wiroonsak

    Subcarrier Clustering for MISO-OFDM Channels with Quantized Beamforming Kritsada Mamat the capacity [1] and link reliability. Thus, many current and future wireless standards are based on multiple antenna. For a multiple-input single-output (MISO) channel, beamforming is a simple and effective method

  8. Coded Adaptive Linear Precoded Discrete Multitone Over PLC Channel

    E-Print Network [OSTI]

    Boyer, Edmond

    Coded Adaptive Linear Precoded Discrete Multitone Over PLC Channel Fahad Syed Muhammmad, Jean- DMT system is presented in the power line communication (PLC) context with a loading algorithm which spectral density constraint. Using a multipath model of PLC channel, it is shown that the proposed coded

  9. Interactive Secret Key Generation over Reciprocal Fading Channels

    E-Print Network [OSTI]

    Khisti, Ashish

    Interactive Secret Key Generation over Reciprocal Fading Channels Ashish Khisti Dept. of Electrical--We study a two-terminal secret-key generation problem over a two-way, approximately reciprocal, block of the secret-key is gen- erated from the correlated channel state sequences by creating omniscience between

  10. Secret-Key Generation over Reciprocal Fading Channels

    E-Print Network [OSTI]

    Khisti, Ashish

    Secret-Key Generation over Reciprocal Fading Channels Ashish Khisti Department of Electrical and Computer Engineering University of Toronto Nov. 14, 2012 #12;Motivation Secret-Key Generation in Wireless, 2012 2/ 22 #12;Motivation Secret-Key Generation in Wireless Fading Channels A B KA KB Forward

  11. Secret-Key Generation from Channel Reciprocity: A Separation Approach

    E-Print Network [OSTI]

    Khisti, Ashish

    Secret-Key Generation from Channel Reciprocity: A Separation Approach Ashish Khisti Department: Secret-Key Generation Secure Message Transmission Physical Layer Authentication Jamming Resistance Feb 11, 2013 2/ 20 #12;Motivation Secret-Key Generation in Wireless Fading Channels A B KA KB Forward

  12. Secret-Key Generation using Correlated Sources and Channels

    E-Print Network [OSTI]

    Khisti, Ashish

    1 Secret-Key Generation using Correlated Sources and Channels Ashish Khisti, Member, IEEE of generating a shared secret key between two terminals in a joint source-channel setup -- the terminals to correlated discrete memoryless source sequences. We establish lower and upper bounds on the secret

  13. Fabrication of 10 nm enclosed nanofluidic channels and Zhaoning Yu

    E-Print Network [OSTI]

    Fabrication of 10 nm enclosed nanofluidic channels Han Caoa) and Zhaoning Yu Nanostructure wafers . The nanofluidic channels were further narrowed and sealed by techniques that are based- tremely small nanofluidic structures need to be fabricated and used as matrices for the manipulation

  14. Optimizing Budget Allocation Among Channels and Influencers Iftah Gamzu

    E-Print Network [OSTI]

    Shamir, Ron

    Optimizing Budget Allocation Among Channels and Influencers Noga Alon Iftah Gamzu Moshe Tennenholtz in a marketing plan deals with the allocation of a given budget among media channels in order to maximize budget needs to be distributed among a set of potential influencers in a way that provides high

  15. Water Transport in Hydrophilic Channels of Nafion (DMR 0819860)

    E-Print Network [OSTI]

    Petta, Jason

    (RH) that open up the ion channels for optimal proton transport. Nafion, a polymer used for fuel cells Benziger, Princeton University Sr Fuel cells convert chemical energy to electrical energy by transporting protons through ion conducting channels in polymer membranes. Improving proton conduction will make fuel

  16. TECHNICAL PAPER Fabrication of microfluidic device channel using a photopolymer

    E-Print Network [OSTI]

    and industry areas (Manz et al. 1990). The technology allows designers to create small, portable, robust, low-costTECHNICAL PAPER Fabrication of microfluidic device channel using a photopolymer for colloidal of fabricating microfluidic device channels for bio-nanoelectronics sys- tem by using high performance epoxy

  17. Transverse flow in thin superhydrophobic channels Franois Feuillebois,1

    E-Print Network [OSTI]

    Bazant, Martin Z.

    Transverse flow in thin superhydrophobic channels François Feuillebois,1 Martin Z. Bazant,2 in superhydrophobic channels. Our focus is on the canonical micro- and nanofluidic geometry of a parallel are possible. Optimized superhydrophobic surfaces may find applications in passive microfluidic mixing

  18. Design and analysis of iteratively decodable codes for ISI channels 

    E-Print Network [OSTI]

    Doan, Dung Ngoc

    2005-11-01T23:59:59.000Z

    B from the capacity have been designed in the literature. In this dissertation, we will focus on the design and analysis of near-capacity achieving codes for another important class of channels, namely inter-symbol interference (ISI)channels. We propose...

  19. Robust concatenated codes for the slow Rayleigh fading channel

    E-Print Network [OSTI]

    Hsu, Teh-Hsuan

    2009-05-15T23:59:59.000Z

    In this thesis, we design a robust concatenated code for the Multiple-Input Multiple-Output (MIMO) system in the presence of slow Rayleigh fading with no channel side information at the transmitter (no CSIT) and perfect channel side information...

  20. On Ergodic Secrecy Capacity for Gaussian MISO Wiretap Channels

    E-Print Network [OSTI]

    Li, Jiangyuan

    2010-01-01T23:59:59.000Z

    A Gaussian multiple-input single-output (MISO) wiretap channel model is considered, where there exists a transmitter equipped with multiple antennas, a legitimate receiver and an eavesdropper each equipped with a single antenna. We study the problem of finding the optimal input covariance that achieves ergodic secrecy capacity subject to a power constraint where only statistical information about the eavesdropper channel is available at the transmitter. This is a non-convex optimization problem that is in general difficult to solve. Existing results address the case in which the eavesdropper or/and legitimate channels have independent and identically distributed Gaussian entries with zero-mean and unit-variance, i.e., the channels have trivial covariances. This paper addresses the general case where eavesdropper and legitimate channels have nontrivial covariances. A set of equations describing the optimal input covariance matrix are proposed along with an algorithm to obtain the solution. Based on this framew...

  1. Designer proton-channel transgenic algae for photobiological hydrogen production

    DOE Patents [OSTI]

    Lee, James Weifu (Knoxville, TN)

    2011-04-26T23:59:59.000Z

    A designer proton-channel transgenic alga for photobiological hydrogen production that is specifically designed for production of molecular hydrogen (H.sub.2) through photosynthetic water splitting. The designer transgenic alga includes proton-conductive channels that are expressed to produce such uncoupler proteins in an amount sufficient to increase the algal H.sub.2 productivity. In one embodiment the designer proton-channel transgene is a nucleic acid construct (300) including a PCR forward primer (302), an externally inducible promoter (304), a transit targeting sequence (306), a designer proton-channel encoding sequence (308), a transcription and translation terminator (310), and a PCR reverse primer (312). In various embodiments, the designer proton-channel transgenic algae are used with a gas-separation system (500) and a gas-products-separation and utilization system (600) for photobiological H.sub.2 production.

  2. Two-photon Photoemission of Organic Semiconductor Molecules on Ag(111)

    E-Print Network [OSTI]

    Yang, Aram

    2008-01-01T23:59:59.000Z

    Supramolecular organization in ultra-thin ?lms of alpha-sexithiophene on sili- con dioxide. Nature Materials,

  3. A two photon absorption laser induced fluorescence diagnostic for fusion plasmas

    SciTech Connect (OSTI)

    Magee, R. M.; Galante, M. E.; McCarren, D.; Scime, E. E. [Physics Department, West Virginia University, Morgantown, West Virginia 26506 (United States); Boivin, R. L.; Brooks, N. H.; Groebner, R. J.; Hill, D. N. [General Atomics, San Diego, California 92121 (United States); Porter, G. D. [Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)

    2012-10-15T23:59:59.000Z

    The quality of plasma produced in a magnetic confinement fusion device is influenced to a large extent by the neutral gas surrounding the plasma. The plasma is fueled by the ionization of neutrals, and charge exchange interactions between edge neutrals and plasma ions are a sink of energy and momentum. Here we describe a diagnostic capable of measuring the spatial distribution of neutral gas in a magnetically confined fusion plasma. A high intensity (5 MW/cm{sup 2}), narrow bandwidth (0.1 cm{sup -1}) laser is injected into a hydrogen plasma to excite the Lyman {beta} transition via the simultaneous absorption of two 205 nm photons. The absorption rate, determined by measurement of subsequent Balmer {alpha} emission, is proportional to the number of particles with a given velocity. Calibration is performed in situ by filling the chamber to a known pressure of neutral krypton and exciting a transition close in wavelength to that used in hydrogen. We present details of the calibration procedure, including a technique for identifying saturation broadening, measurements of the neutral density profile in a hydrogen helicon plasma, and discuss the application of the diagnostic to plasmas in the DIII-D tokamak.

  4. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

    E-Print Network [OSTI]

    Johns, James

    2010-01-01T23:59:59.000Z

    Laser System The tunable ultrafast pulses used in thesewhen exposed to ultrafast pulses, and that this degradationthe UV pulse. 4.3 Results Here, we present ultrafast time

  5. Two-photon Photo-emission of Ultrathin Film PTCDA Morphologies on Ag(111)

    E-Print Network [OSTI]

    Yang, Aram

    2008-01-01T23:59:59.000Z

    to generate tunable ultrafast pulses of ?100 fs durationIn short, a pulse from a commercial ultrafast oscillator is

  6. Two photon absorption and third harmonic generation micro- spectroscopy : hemoglobin and other compounds

    E-Print Network [OSTI]

    Clay, Gabriel Omar

    2006-01-01T23:59:59.000Z

    As the absorption of ultrafast pulses in the vessel lumen isfocussed, ultrafast, ~2 nano-joule laser pulses at selectedwith ultrafast ( ~100-200 fs in duration) laser pulses at

  7. Characterization of Two-Photon Excitation: Coherent Control and Nonlinear Propagation in Transparent Media 

    E-Print Network [OSTI]

    Poudel, Milan Prasad

    2010-10-12T23:59:59.000Z

    Coherent control of laser induced processes is based on the quantum interference among multiple excitation pathways. Progress in the field has been fueled by advances in pulse shaping techniques, allowing modulation of phase and amplitude across...

  8. Fast-scanning two-photon fluorescence imaging based on a microelectromechanical systems two-

    E-Print Network [OSTI]

    Schnitzer, Mark

    , electric potential, electrical field, or illumination. Microelectromechanical systems (MEMS) designed

  9. Experimenting Liver Fibrosis Diagnostic by Two Photon Excitation Microscopy and Bag-of-Features Image Classification

    E-Print Network [OSTI]

    Stanciu, Stefan G.

    The accurate staging of liver fibrosis is of paramount importance to determine the state of disease progression, therapy responses, and to optimize disease treatment strategies. Non-linear optical microscopy techniques ...

  10. applying two-photon excitation: Topics by E-print Network

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

    of Kansas - KU ScholarWorks Summary: or gener- ate dangerous amounts of hydrogen gas in radioactive waste storage tanks.1 Radiolysis and photolysis experiments pro- vide a window...

  11. Non-local geometric phase in two-photon interferometry , O. Alibart1

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    in Hanbury Brown-Twiss polarized intensity interferometry. The experiment involves two independent, polar Brown and Twiss (HB-T), who performed inten- sity interferometry experiments using incoherent thermal

  12. Nonclassical effects in two-photon interference experiments: event-by-event simulations

    E-Print Network [OSTI]

    -photon interference experiments with two independent sources, like the Hanbury Brown-Twiss experiment: Interference, Hanbury Brown-Twiss experiment, Ghosh-Mandel experiment, quantum theory, discrete

  13. Self-standing aligned fiber scaffold fabrication by two photon photopolymerization

    E-Print Network [OSTI]

    Hidai, Hirofumi; Jeon, Hojeong; Hwang, David J.; Grigoropoulos, Costas P.

    2009-01-01T23:59:59.000Z

    10.1038/35089130 A.S. Kewitsch, A. Yariv, Opt. Lett. 21(1),self-focusing (Kewitsch and Yariv 1996), self-growing (Shoji

  14. Hard two photon processes \\gamma\\gamma --> M_2 M_1 in QCD

    E-Print Network [OSTI]

    Chernyak, Victor L

    2012-01-01T23:59:59.000Z

    A short review of leading term QCD predictions vs those of the handbag model for large angle cross sections \\gamma\\gamma --> P_2 P_1 (P is the pseudoscalar meson \\pi^{\\pm,o}, K^{\\pm,o}, \\eta), and for \\gamma\\gamma --> V_2 V_1 (V is the neutral vector meson \\rho^o, \\omega, \\phi), in comparison with Belle Collaboration measuments

  15. Two-photon double ionization of the helium atom by ultrashort pulses

    E-Print Network [OSTI]

    Palacios, Alicia

    2010-01-01T23:59:59.000Z

    ionization of He Kurka M, Rudenko A, Foucar L, Kuhnel K U,2000 Phys. Rev. A 62, 032706. Rudenko A, Foucar L, Kurka M,of atoms (Kurka et al. 2009, Rudenko et al. 2008, Sorokin et

  16. Second-order autocorrelation of XUV FEL pulses via time resolved two-photon single

    E-Print Network [OSTI]

    Kling, Matthias

    R. Moshammer,1,2 Th. Pfeifer,1 A. Rudenko,2,3 Y. H. Jiang,1,2 L. Foucar,2,3 M. Kurka,1,2 K. U. Feist, D. A. Horner, A. Rudenko, Y. H. Jiang, K. U. Kühnel, L. Foucar, T. N. Rescigno, C. W. McCurdy, R

  17. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

    E-Print Network [OSTI]

    Johns, James E.

    2010-01-01T23:59:59.000Z

    performance and efficiency of photovoltaics, field effectvoltage and efficiency of organic photovoltaics. Despite

  18. Time?resolved two?photon induced anisotropy decay: The rotational diffusion regime

    E-Print Network [OSTI]

    Wan, Chaozhi; Johnson, Carey K.

    1994-09-01T23:59:59.000Z

    tensor with nonzero elements S xx and S yy' All other elements are assumed to vanish and the orientation of the secondary transition dipole is taken to be along the x axis. In this case, (A~:6)2 { (2 9 ) _ E(2)t r l(t)=7(2+p2) (1+YJC) 2+P + YJ PC e 0... +(C-YJ)[ (2+p2)C- ~ p]e-E~2)t} (36) and _ (A~:6)2 { (2 6 ) -E(2)t r2(t)- 7(1 +3p2) (1 +YJC) 3P -1 + V3 PC e 0 +(C-YJ)[ (3P2-1)C- ~ p]e-E~2)l (37) where A(2) C 2,0 = A(2)' 0,0 (38) (39) It is apparent that rl and r2 in Eqs. (36) and (37...

  19. Membrane potential detection with second-harmonic generation and two-photon

    E-Print Network [OSTI]

    the performance of TPEF and SHG microscopy for membrane potential imaging. We argue that electrochromic TPEF sensitivities in the case of both electrochromic and orientational response mechanisms. Despite their similar.elsevier.com/locate/optcom #12;the phenomenon of electrochromism, which is rou- tinely used for membrane potential detection

  20. Characterization of Two-Photon Excitation: Coherent Control and Nonlinear Propagation in Transparent Media

    E-Print Network [OSTI]

    Poudel, Milan Prasad

    2010-10-12T23:59:59.000Z

    CEO detection [26]. .....................................................................16 2.7 Beat signal from the Rainbow oscillator (35 dB)...........................................16 2.8 Regenerative Cavity [23... inside a stretcher by separating in time its Fig. 2.3. Schematic of the (a) grating stretcher and (b) grating compressor b)a) 12 frequency components. Then this pulse is directed into the amplifier regenerative cavity...

  1. Reconstruction of a multimode entangled state using a two-photon phase-sensitive linear amplifier

    E-Print Network [OSTI]

    Ahmad, M.; Qamar, S.; Zubairy, M. Suhail

    2003-01-01T23:59:59.000Z

    inverse Radon transformation. This scheme is insensitive to the noise associated with the nonunit efficiency of the detector in the homodyne detection measurement scheme....

  2. Confocal two photon emission microscopy: A new approach to waveguide imaging

    E-Print Network [OSTI]

    Dierolf, Volkmar

    Based on earlier studies of the interaction eects between Er3+ and Ti4+ ions in Ti:LiNbO3 wave- guides, vod2@lehigh.edu, Fax: 49-610-758-5730 1 #12;I. INTRODUCTION AND BACKGROUND Lithium niobate (LiNbO3) plays an important role in integrated optics due to its favorable optical properties and the possibility

  3. Enhanced Background Rejection in Thick Tissue with Differential-Aberration Two-Photon Microscopy

    E-Print Network [OSTI]

    to superficial tissue damage, then the power density of the ballistic light near the surface can be so high and the ballistic light so weak that the power density of the ballistic light cannot compete at the beam focus can lead to significant power densities near the tissue surface. If the tissue

  4. Atom microscopy via two-photon spontaneous emission spectroscopy RID A-5077-2009

    E-Print Network [OSTI]

    Qamar, Sajid; Evers, Joerg; Zubairy, M. Suhail

    2009-01-01T23:59:59.000Z

    #1;e?i#1;#7;k?#6;2#2;t#3;e?i#6;1tC1#1;t#2; ? ei#6;1tC2#1;t#2;#4; + 1 2#8;q gqe i#1;#7;q+#6;2#2;tCe k,q#1;t#2; , #1;6c#2; C? 4 k#1;t#2; = 1 2 gk #1;e?i#1;#7;k+#6;2#2;t#3;e?i#6;1tC1#1;t#2; ? ei#6;1tC2#1;t#2;#4; ? 1 2#8;q gqe i#1;#7;q?#6...;2#2;tCe k,q#1;t#2; , #1;6d#2; C? e k,q#1;t#2; = 1 2gq #1;e?i#7;qt#3;e?i#6;2tC3k#1;t#2; ? C4k#1;t#2;ei#6;2t#4; . #1;6e#2; In the long-time limit, #5;#12;#1;t ? #14;#2;#6; = #8; k,q Ce k,q#1;#14;#2;#5;e,1k,1q#6; . #1;7#2; The final...

  5. Three-dimensional cardiac architecture determined by two-photon microtomy

    E-Print Network [OSTI]

    Huang, Hayden

    Cardiac architecture is inherently three-dimensional, yet most characterizations rely on two-dimensional histological slices or dissociated cells, which remove the native geometry of the heart. We previously developed a ...

  6. Search for resonances decaying to ?[subscript c]?[superscript +]?[superscript -] in two-photon interactions

    E-Print Network [OSTI]

    Cowan, Ray Franklin

    We report a study of the process ???X??[subscript c]?[superscript +]?[superscript -], where X stands for one of the resonances ?[subscript c2](1P), ?[subscript c](2S), X(3872), X(3915), or ?[subscript c2](2P). The analysis ...

  7. Electron Dynamics and Symmetries at the Metal-Molecule Interface Probed by Two Photon Photoemission

    E-Print Network [OSTI]

    Muller, Eric Anton

    2012-01-01T23:59:59.000Z

    response such as supercapacitors may be able to overcomein the bulk[88]. In supercapacitors, power is stored by athe molecular mechanisms governing supercapacitors and other

  8. Proton form factors and two-photon exchange contribution to elastic electron-proton scattering

    E-Print Network [OSTI]

    and unpolarized data! R. C. Walker, et al. PRD 49 (1994) 5671. I. A. Qattan, et al. PRL 94 (2005) 142301. M. K. Jones, et al. PRL 84 (2000) 1398. V. Punjabi, et al. PRC 71 (2005) 055202. O. Gayou, et al. PRL 88 (2002) 092301. A. J. R. Puckett, et al. PRL 104 (2010) 242301. Alexander Gramolin (Budker INP) Proton

  9. Watching Electrons Transfer from Metals to Insulators using Two Photon Photoemission

    E-Print Network [OSTI]

    Johns, James

    2010-01-01T23:59:59.000Z

    Phys. Rev. Lett. J1 - PRL 2004, 93, (15). Fauster, T. a.Phys. Rev. Lett. J1 - PRL 2004, vol.93, no.21, 215702/1-4.Surface. Phys. Rev. Lett. J1 - PRL 1998, 80, (19), 4265 LP -

  10. Optical flux lattices for two-photon dressed N. R. Cooper and J. Dalibard

    E-Print Network [OSTI]

    Dalibard, Jean

    the EPL website to read the latest articles published in cutting-edge fields of research from across of the referees to making all final acceptance decisions Impact Factor ­ The 2010 Impact Factor is 2.753; your Journal Citation Reports IMPACT FACTOR 500 000full text downloads in 2010 OVER 30 DAYS 16 961 average

  11. Autocorrelation measurements of free-electron laser radiation using a two-photon QWIP

    E-Print Network [OSTI]

    Perera, A. G. Unil

    ]. Besides thermography, the high electrical bandwidth of QWIPs provides interesting opportunities in new

  12. Electronic structure of liquid water from polarization-dependent two-photon absorption spectroscopy

    E-Print Network [OSTI]

    Elles, Christopher G.; Rivera, Christopher A.; Zhang, Yuyuan; Pieniazek, Piotr A.; Bradforth, Stephen E.

    2009-02-26T23:59:59.000Z

    the absorption at many wavelengths simultaneously. A preresonance enhancement of the absolute 2PA cross section is observed when the pump-photon energy increases from 4.6 to 6.2 eV. The absorption cross section also depends on the relative polarization...

  13. Frustrated Two-Photon Creation in a Time-Dependent Cavity

    SciTech Connect (OSTI)

    Branning, David [Department of Physics, Trinity College, 300 Summit St., Hartford, CT, 06106 (United States)

    2009-03-10T23:59:59.000Z

    In the process of parametric downconversion, a high-energy photon is annihilated to create a pair of lower-energy photons within a nonlinear dielectric material. It was shown some years ago that this process can be modified by quantum interference, by reflecting the high-energy and low-energy light back into the dielectric. The suppression or enhancement of the downconversion rate is analogous to the phenomenon of inhibited spontaneous emission that occurs when an excited atom is placed in a cavity whose allowed modes cannot support the spontaneous emission. In this case, the atom remains excited--but then, how does it interact with the cavity? If the cavity mirror were replaced by a detector, could photons be counted immediately, or only after some time delay? Our experiment uses spontaneous downconversion, a 2-m long cavity, and a fast optical switch to obtain the answer.

  14. Two-Photon Study on the Electronic Interactions between the First Excited

    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. DOE Office of ScienceandMesa del SolStrengthening aTurbulence may be key to "fastTwist SolvesTwoSinglet States

  15. Methods for consistent forewarning of critical events across multiple data channels

    DOE Patents [OSTI]

    Hively, Lee M.

    2006-11-21T23:59:59.000Z

    This invention teaches further method improvements to forewarn of critical events via phase-space dissimilarity analysis of data from biomedical equipment, mechanical devices, and other physical processes. One improvement involves conversion of time-serial data into equiprobable symbols. A second improvement is a method to maximize the channel-consistent total-true rate of forewarning from a plurality of data channels over multiple data sets from the same patient or process. This total-true rate requires resolution of the forewarning indications into true positives, true negatives, false positives and false negatives. A third improvement is the use of various objective functions, as derived from the phase-space dissimilarity measures, to give the best forewarning indication. A fourth improvement uses various search strategies over the phase-space analysis parameters to maximize said objective functions. A fifth improvement shows the usefulness of the method for various biomedical and machine applications.

  16. Microfluidic pumping through miniaturized channels driven by ultra-high frequency surface acoustic waves

    SciTech Connect (OSTI)

    Shilton, Richie J., E-mail: richard.shilton@iit.it [Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); Travagliati, Marco [Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy); Beltram, Fabio [NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy); Center for Nanotechnology Innovation @ NEST, Istituto Italiano di Tecnologia, Piazza San Silvestro 12, 56127 Pisa (Italy); Cecchini, Marco, E-mail: marco.cecchini@nano.cnr.it [NEST, Scuola Normale Superiore and Istituto Nanoscienze-CNR, Piazza San Silvestro 12, 56127 Pisa (Italy)

    2014-08-18T23:59:59.000Z

    Surface acoustic waves (SAWs) are an effective means to pump fluids through microchannel arrays within fully portable systems. The SAW-driven acoustic counterflow pumping process relies on a cascade phenomenon consisting of SAW transmission through the microchannel, SAW-driven fluid atomization, and subsequent coalescence. Here, we investigate miniaturization of device design, and study both SAW transmission through microchannels and the onset of SAW-driven atomization up to the ultra-high-frequency regime. Within the frequency range from 47.8 MHz to 754?MHz, we show that the acoustic power required to initiate SAW atomization remains constant, while transmission through microchannels is most effective when the channel widths w???10??, where ? is the SAW wavelength. By exploiting the enhanced SAW transmission through narrower channels at ultra-high frequencies, we discuss the relevant frequency-dependent length scales and demonstrate the scaling down of internal flow patterns and discuss their impact on device miniaturization strategies.

  17. Identification of genes from pattern formation, tyrosine kinase, and potassium channel families by DNA amplification

    SciTech Connect (OSTI)

    Kamb, A.; Weir, M.; Rudy, B.; Varmus, H.; Kenyon, C. (Univ. of California, San Francisco (USA))

    1989-06-01T23:59:59.000Z

    The study of gene family members has been aided by the isolation of related genes on the basis of DNA homology. The authors have adapted the polymerase chain reaction to screen animal genomes very rapidly and reliably for likely gene family members. Using conserved amino acid sequences to design degenerate oligonucleotide primers, they have shown that the genome of the nematode Caenorhabditis elegans contains sequences homologous to many Drosophila genes involved in pattern formation, including the segment polarity gene wingless (vertebrate int-1), and homeobox sequences characteristic of the Antennapedia, engrailed, and paired families. In addition, they have used this method to show that C. elegans contains at least five different sequences homologous to genes in the tyrosine kinase family. Lastly, they have isolated six potassium channel sequences from humans, a result that validates the utility of the method with large genomes and suggests that human potassium channel gene diversity may be extensive.

  18. Mars outflow channels: A reappraisal of the estimation of water flow velocities from water depths, regional slopes, and channel floor

    E-Print Network [OSTI]

    Head III, James William

    of estimating water flow velocities in Martian outflow channels using equations based on the Darcy of the Manning equation should be replaced by the modern form or, preferably, by the Darcy-Weisbach equation channel systems on Mars have relied widely on various versions of the Manning equation. This has led

  19. The conserved carboxy-terminal region of the ammonia channel AmtB plays a critical role in channel function

    E-Print Network [OSTI]

    Merrick, Mike

    The conserved carboxy-terminal region of the ammonia channel AmtB plays a critical role in channel-terminal residues can have very marked effects. Using the Escherichia coli AmtB protein as a model system for Amt that are best explained in terms of two distinct effects of the C-terminal region on AmtB activity. Residues

  20. apolipoprotein a-i showed: Topics by E-print Network

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

    Creek showing (Candy and Deep Purple claims) is hosted by Middle Devonian carbonate rocks in the southem Rocky Mountains oi British Columbia. The property lies near the...