National Library of Energy BETA

Sample records for wave power density

  1. Effect of electron density profile on power absorption of high frequency electromagnetic waves in plasma

    SciTech Connect (OSTI)

    Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)

    2012-07-15

    Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.

  2. Shear-horizontal surface acoustic wave phononic device with high density filling material for ultra-low power sensing applications

    SciTech Connect (OSTI)

    Richardson, M.; Bhethanabotla, V. R.; Sankaranarayanan, S. K. R. S.

    2014-06-23

    Finite element simulations of a phononic shear-horizontal surface acoustic wave (SAW) sensor based on ST 90°-X Quartz reveal a dramatic reduction in power consumption. The phononic sensor is realized by artificially structuring the delay path to form an acoustic meta-material comprised of a periodic microcavity array incorporating high-density materials such as tantalum or tungsten. Constructive interference of the scattered and secondary reflected waves at every microcavity interface leads to acoustic energy confinement in the high-density regions translating into reduced power loss. Tantalum filled cavities show the best performance while tungsten inclusions create a phononic bandgap. Based on our simulation results, SAW devices with tantalum filled microcavities were fabricated and shown to significantly decrease insertion loss. Our findings offer encouraging prospects for designing low power, highly sensitive portable biosensors.

  3. Stability of an Ultra-Relativistic Blast Wave in an External Medium with a Steep Power-Law Density Profile

    E-Print Network [OSTI]

    Xiaohu Wang; Abraham Loeb; Eli Waxman

    2002-12-22

    We examine the stability of self-similar solutions for an accelerating relativistic blast wave which is generated by a point explosion in an external medium with a steep radial density profile of a power-law index > 4.134. These accelerating solutions apply, for example, to the breakout of a gamma-ray burst outflow from the boundary of a massive star, as assumed in the popular collapsar model. We show that short wavelength perturbations may grow but only by a modest factor <~ 10.

  4. WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01

    A LiBRARY ANL WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITYof Califomia. To be in WAVE-ENERGY DENSITY AND WAVE~HOMENTUMExpress1ons for the wave-energy density and wave-momentum

  5. Global coherence of dust density waves

    SciTech Connect (OSTI)

    Killer, Carsten; Melzer, André

    2014-06-15

    The coherence of self-excited three-dimensional dust density waves has been experimentally investigated by comparing global and local wave properties. For that purpose, three-dimensional dust clouds have been confined in a radio frequency plasma with thermophoretic levitation. Global wave properties have been measured from the line-of-sight integrated dust density obtained from homogenous light extinction measurements. Local wave properties have been obtained from thin, two-dimensional illuminated laser slices of the cloud. By correlating the simultaneous global and local wave properties, the spatial coherence of the waves has been determined. We find that linear waves with small amplitudes tend to be fragmented, featuring an incoherent wave field. Strongly non-linear waves with large amplitudes, however, feature a strong spatial coherence throughout the dust cloud, indicating a high level of synchronization.

  6. Spin- and Pair-Density-Wave Glasses

    E-Print Network [OSTI]

    Mross, David F.

    Spontaneous breaking of translational symmetry, known as density-wave order, is common in nature. However, such states are strongly sensitive to impurities or other forms of frozen disorder leading to fascinating glassy ...

  7. Density shock waves in confined microswimmers

    E-Print Network [OSTI]

    Tsang, Alan Cheng Hou

    2015-01-01

    Motile and driven particles confined in microfluidic channels exhibit interesting emergent behavior from propagating density bands to density shock waves. A deeper understanding of the physical mechanisms responsible for these emergent structures is relevant to a number of physical and biomedical applications. Here, we study the formation of density shock waves in the context of an idealized model of microswimmers confined in a narrow channel and subject to a uniform external flow. Interestingly, these density shock waves exhibit a transition from `subsonic' with compression at the back to `supersonic' with compression at the front of the population as the intensity of the external flow increases. This behavior is the result of a non-trivial interplay between hydrodynamic interactions and geometric confinement, and is confirmed by a novel quasilinear wave model that properly captures the dependence of the shock formation on the external flow. These findings can be used to guide the development of novel mechan...

  8. Using Radio Waves to Control Fusion Plasma Density

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

    Using Radio Waves to Control Fusion Plasma Density Using Radio Waves to Control Fusion Plasma Density Simulations Run at NERSC Support Fusion Experiments at MIT, General Atomics...

  9. Acoustic Kappa-Density Fluctuation Waves in Suprathermal Kappa Function Fluids

    E-Print Network [OSTI]

    Michael R. Collier; Aaron Roberts; Adolfo Vinas

    2007-10-20

    We describe a new wave mode similar to the acoustic wave in which both density and velocity fluctuate. Unlike the acoustic wave in which the underlying distribution is Maxwellian, this new wave mode occurs when the underlying distribution is a suprathermal kappa function and involves fluctuations in the power law index, kappa. This wave mode always propagates faster than the acoustic wave with an equivalent effective temperature and becomes the acoustic wave in the Maxwellian limit as kappa goes to infinity.

  10. Design of Millimeter-Wave Power Ampliers in Silicon /

    E-Print Network [OSTI]

    Kalantari, Nader

    2013-01-01

    1.1 Millimeter-Wave Power Amplifier . . . . . . . . . .ported mm-wave power amplifiers. . . . . . . . . . . . . . .GHz Tapered Constructive Wave Power 3.1 Traveling Wave Power

  11. Nuclear spin-density wave theory

    E-Print Network [OSTI]

    Yao Cheng

    2009-09-15

    Recently [arXiv:0906.5417], we reported a quantum phase transition of 103mRh excited by bremsstrahlung pumping. The long-lived Moessbauer excitation is delocalized as a neutral quasiparticle carrying a spin current. This letter gives a general theory for a nuclear spin-density wave propagating on crystals consisting of identical nuclei with a multipolar transition.

  12. Density waves in the Calogero model - revisited

    SciTech Connect (OSTI)

    Bardek, V. Feinberg, J. Meljanac, S.

    2010-03-15

    The Calogero model bears, in the continuum limit, collective excitations in the form of density waves and solitary modulations of the density of particles. This sector of the spectrum of the model was investigated, mostly within the framework of collective-field theory, by several authors, over the past 15 years or so. In this work we shall concentrate on periodic solutions of the collective BPS-equation (also known as 'finite amplitude density waves'), as well as on periodic solutions of the full static variational equations which vanish periodically (also known as 'large amplitude density waves'). While these solutions are not new, we feel that our analysis and presentation add to the existing literature, as we explain in the text. In addition, we show that these solutions also occur in a certain two-family generalization of the Calogero model, at special points in parameter space. A compendium of useful identities associated with Hilbert transforms, including our own proofs of these identities, appears in Appendix A. In Appendix B we also elucidate in the present paper some fine points having to do with manipulating Hilbert-transforms, which appear ubiquitously in the collective field formalism. Finally, in order to make this paper self-contained, we briefly summarize in Appendix C basic facts about the collective field formulation of the Calogero model.

  13. Energy-momentum Density of Gravitational Waves

    E-Print Network [OSTI]

    Amir M. Abbassi; Saeed Mirshekari

    2014-11-29

    In this paper, we elaborate the problem of energy-momentum in general relativity by energy-momentum prescriptions theory. Our aim is to calculate energy and momentum densities for the general form of gravitational waves. In this connection, we have extended the previous works by using the prescriptions of Bergmann and Tolman. It is shown that they are finite and reasonable. In addition, using Tolman prescription, exactly, leads to same results that have been obtained by Einstein and Papapetrou prescriptions.

  14. Nonlocal theory of electromagnetic wave decay into two electromagnetic waves in a rippled density plasma channel

    SciTech Connect (OSTI)

    Sati, Priti; Tripathi, V. K.

    2012-12-15

    Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.

  15. Competition between superconductivity and spin density wave

    E-Print Network [OSTI]

    Tian De Cao

    2012-08-25

    The Hubbard model has been investigated widely by many authors, while this work may be new in two aspects. One, we focus on the possible effects of the positions of the gaps associated with the pairing and the spin density wave. Two, we suggest that the models with different parameters are appropriate for different materials (or a material in different doped regions). This will lead to some new insights into the high temperature superconductors. It is shown that the SDW can appear at some temperature region when the on-site Coulomb interaction is larger, while the SC requires a decreased U at a lower temperature. This can qualitatively explain the relationship between superconducting and pseudogap states of Cu-based superconductors in underdoped and optimally doped regions. The superinsulator is also discussed.

  16. Catching a Wave: Innovative Wave Energy Device Surfs for Power...

    Office of Environmental Management (EM)

    and cost-effective electricity from clean energy resources, including water. Marine and hydrokinetic (MHK) technologies, which generate power from waves, tides, or...

  17. A restoration model of distorted electron density in wave-cutoff probe measurement

    SciTech Connect (OSTI)

    Jun, Hyun-Su Lee, Yun-Seong

    2014-02-15

    This study investigates the problem of electron density distortion and how the density can be restored in a wave-cutoff probe. Despite recent plasma diagnostics research using a wave-cutoff probe, the problem of electron density distortion caused by plasma conditions has not been resolved. Experimental results indicate that electron density measured using the wave-cutoff method is highly susceptible to variations in the probe tip gap. This electron density distortion is caused by the bulk plasma disturbance between probe tips, and it must be removed for calculating the absolute electron density. To do this, a detailed analytic model was developed using the power balance equation near probe tips. This model demonstrates the characteristics of plasma distortion in wave-cutoff probe measurement and successfully restored the absolute value of electron density with varying probe tip gaps.

  18. Considering Air Density in Wind Power Production

    E-Print Network [OSTI]

    Zénó Farkas

    2011-03-11

    In the wind power production calculations the air density is usually considered as constant in time. Using the CIPM-2007 equation for the density of moist air as a function of air temperature, air pressure and relative humidity, we show that it is worth taking the variation of the air density into account, because higher accuracy can be obtained in the calculation of the power production for little effort.

  19. Considering Air Density in Wind Power Production

    E-Print Network [OSTI]

    Farkas, Zénó

    2011-01-01

    In the wind power production calculations the air density is usually considered as constant in time. Using the CIPM-2007 equation for the density of moist air as a function of air temperature, air pressure and relative humidity, we show that it is worth taking the variation of the air density into account, because higher accuracy can be obtained in the calculation of the power production for little effort.

  20. Wave Power Demonstration Project at Reedsport, Oregon

    SciTech Connect (OSTI)

    Mekhiche, Mike; Downie, Bruce

    2013-10-21

    Ocean wave power can be a significant source of large?scale, renewable energy for the US electrical grid. The Electrical Power Research Institute (EPRI) conservatively estimated that 20% of all US electricity could be generated by wave energy. Ocean Power Technologies, Inc. (OPT), with funding from private sources and the US Navy, developed the PowerBuoy? to generate renewable energy from the readily available power in ocean waves. OPT's PowerBuoy converts the energy in ocean waves to electricity using the rise and fall of waves to move the buoy up and down (mechanical stroking) which drives an electric generator. This electricity is then conditioned and transmitted ashore as high?voltage power via underwater cable. OPT's wave power generation system includes sophisticated techniques to automatically tune the system for efficient conversion of random wave energy into low cost green electricity, for disconnecting the system in large waves for hardware safety and protection, and for automatically restoring operation when wave conditions normalize. As the first utility scale wave power project in the US, the Wave Power Demonstration Project at Reedsport, OR, will consist of 10 PowerBuoys located 2.5 miles off the coast. This U.S. Department of Energy Grant funding along with funding from PNGC Power, an Oregon?based electric power cooperative, was utilized for the design completion, fabrication, assembly and factory testing of the first PowerBuoy for the Reedsport project. At this time, the design and fabrication of this first PowerBuoy and factory testing of the power take?off subsystem are complete; additionally the power take?off subsystem has been successfully integrated into the spar.

  1. High-Efficiency and High-Power CMOS Power Amplifiers for Millimeter-Wave Applications /

    E-Print Network [OSTI]

    Agah, Amir

    2013-01-01

    of stacked-FET millimeter-wave power amplifiers,” IEEECMOS Millimeter-Wave Power Amplifiers .dual-path, millimeter-wave power amplifier with 20 dBm

  2. Spiral density wave generation by vortices in Keplerian flows

    E-Print Network [OSTI]

    G. Bodo; G. Chagelishvili; G. Murante; A. Tevzadze; P. Rossi; A. Ferrari

    2005-03-22

    We perform a detailed analytical and numerical study of the dynamics of perturbations (vortex/aperiodic mode, Rossby and spiral-density waves) in 2D compressible disks with a Keplerian law of rotation. We draw attention to the process of spiral-density wave generation from vortices, discussing, in particular, the initial, most peculiar stages of wave emission. We show that the linear phenomenon of wave generation by vortices in smooth (without inflection points) shear flows found by using the so-called non-modal approach, is directly applicable to the present case. After an analytical non-modal description of the physics and characteristics of the spiral-density wave generation/propagation in the local shearing-sheet model, we follow the process of wave generation by small amplitude coherent circular vortex structures, by direct global numerical simulation, describing the main features of the generated waves.

  3. Secondary dust density waves excited by nonlinear dust acoustic waves J. R. Heinrich,1,a)

    E-Print Network [OSTI]

    Merlino, Robert L.

    Secondary dust density waves excited by nonlinear dust acoustic waves J. R. Heinrich,1,a) S.-H. Kim amplitude ðnd=nd0 > 2Þ dust acoustic waves (DAW) that were spontaneously excited in a dc glow discharge dusty plasma in the moderately coupled, C $ 1; state. The high amplitude dust acoustic waves produced

  4. High power density solid oxide fuel cells

    DOE Patents [OSTI]

    Pham, Ai Quoc; Glass, Robert S.

    2004-10-12

    A method for producing ultra-high power density solid oxide fuel cells (SOFCs). The method involves the formation of a multilayer structure cells wherein a buffer layer of doped-ceria is deposited intermediate a zirconia electrolyte and a cobalt iron based electrode using a colloidal spray deposition (CSD) technique. For example, a cobalt iron based cathode composed of (La,Sr)(Co,Fe)O (LSCF) may be deposited on a zirconia electrolyte via a buffer layer of doped-ceria deposited by the CSD technique. The thus formed SOFC have a power density of 1400 mW/cm.sup.2 at 600.degree. C. and 900 mW/cm.sup.2 at 700.degree. C. which constitutes a 2-3 times increased in power density over conventionally produced SOFCs.

  5. Optical Properties of the Charge-Density-Wave Polychalcogenide...

    Office of Scientific and Technical Information (OSTI)

    Optical Properties of the Charge-Density-Wave Polychalcogenide Compounds R2Te5 (RNd, Sm and Gd) Citation Details In-Document Search Title: Optical Properties of the...

  6. Optical Properties of the Charge-Density-Wave Polychalcogenide...

    Office of Scientific and Technical Information (OSTI)

    the rare-earth polychalcogenide Rsub 2Tesub 5 (R Nd, Sm and Gd) charge-density-wave (CDW) compounds by optical methods. From the absorption spectrum we extract the...

  7. Effect of Chemical Pressure on the Charge Density Wave Transition...

    Office of Scientific and Technical Information (OSTI)

    Effect of Chemical Pressure on the Charge Density Wave Transition in Rare-Earth Tritellurides RTe3 Citation Details In-Document Search Title: Effect of Chemical Pressure on the...

  8. Liquid Walls Innovative High Power Density Concepts

    E-Print Network [OSTI]

    California at Los Angeles, University of

    erosion as limiting factors -Results in smaller and lower cost components (chambLiquid Walls Innovative High Power Density Concepts (Based on the APEX Study) http for the Chamber Technology that can: 1. Improve the vision for an attractive fusion energy system 2. Lower

  9. The excitation of spiral density waves through turbulent fluctuations in accretion discs I: WKBJ theory

    E-Print Network [OSTI]

    T. Heinemann; J. C. B. Papaloizou

    2009-04-30

    We study and elucidate the mechanism of spiral density wave excitation in a differentially rotating turbulent flow. We formulate a set of wave equations with sources that are only non-zero in the presence of turbulent fluctuations. We solve these in a shearing box domain using a WKBJ method. It is found that, for a particular azimuthal wave length, the wave excitation occurs through a sequence of regularly spaced swings during which the wave changes from leading to trailing form. This is a generic process that is expected to occur in shearing discs with turbulence. Trailing waves of equal amplitude propagating in opposite directions are produced, both of which produce an outward angular momentum flux that we give expressions for as functions of the disc parameters and azimuthal wave length. By solving the wave amplitude equations numerically we justify the WKBJ approach for a Keplerian rotation law for all parameter regimes of interest. In order to quantify the wave excitation completely the important wave source terms need to be specified. Assuming conditions of weak nonlinearity, these can be identified and are associated with a quantity related to the potential vorticity, being the only survivors in the linear regime. Under the additional assumption that the source has a flat power spectrum at long azimuthal wave lengths, the optimal azimuthal wave length produced is found to be determined solely by the WKBJ response and is estimated to be 2 pi H, with H being the nominal disc scale height.

  10. Density waves in the shearing sheet III. Disc heating

    E-Print Network [OSTI]

    B. Fuchs

    2001-04-25

    The problem of dynamical heating of galactic discs by spiral density waves is discussed using the shearing sheet model. The secular evolution of the disc is described quantitatively by a diffusion equation for the distribution function of stars in the space spanned by integrals of motion of the stars, in particular the radial action integral and an integral related to the angular momentum. Specifically, disc heating by a succession of transient, `swing amplified' density waves is studied. It is shown that such density waves lead predominantly to diffusion of stars in radial action space. The stochastical changes of angular momenta of the stars and the corresponding stochastic changes of the guiding centre radii of the stellar orbits induced by this process are much smaller.

  11. Turbulence transition and internal wave generation in density stratified jets

    E-Print Network [OSTI]

    Sutherland, Bruce

    Turbulence transition and internal wave generation in density stratified jets B. FL Sutherland (Received 3 June 1993; accepted 18 November 1993) The nonlinear evolution of an unstable symmetric jet torques. In this case, the mean flow of the fully evolved jet is stable to subharmonic disturbances

  12. Innovative fuel designs for high power density pressurized water reactor

    E-Print Network [OSTI]

    Feng, Dandong, Ph. D. Massachusetts Institute of Technology

    2006-01-01

    One of the ways to lower the cost of nuclear energy is to increase the power density of the reactor core. Features of fuel design that enhance the potential for high power density are derived based on characteristics of ...

  13. Design of annular fuel for high power density BWRs

    E-Print Network [OSTI]

    Morra, Paolo

    2005-01-01

    Enabling high power density in the core of Boiling Water Reactors (BWRs) is economically profitable for existing or new reactors. In this work, we examine the potential for increasing the power density in BWR plants by ...

  14. Whistler Wave Interaction with a Density Striation: A Laboratory Investigation of an Auroral Process

    E-Print Network [OSTI]

    California at Los Angles, University of

    1 Whistler Wave Interaction with a Density Striation: A Laboratory Investigation of an Auroral Angeles, California 90095 Whistler waves are launched toward a field-aligned density striation the wave-launching antenna, besides a reflected and a transmitted whistler wave, lower hybrid waves

  15. Generation of density inhomogeneities by magnetohydrodynamic waves in two dimensions

    E-Print Network [OSTI]

    S. Van Loo; S. A. E. G. Falle; T. W. Hartquist

    2006-05-10

    Using two dimensional simulations, we study the formation of structures with a high-density contrast by magnetohydrodynamic waves in regions in which the ratio of thermal to magnetic pressure is small. The initial state is a uniform background perturbed by fast-mode wave. Our most significant result is that dense structures persist for far longer in a two-dimensional simulation than in the one-dimensional case. Once formed, these structures persist as long as the fast-mode amplitude remains high.

  16. Optimal Base Station Density for Power Efficiency in Cellular Networks

    E-Print Network [OSTI]

    Haenggi, Martin

    Optimal Base Station Density for Power Efficiency in Cellular Networks Sanglap Sarkar, Radha, power consumption, power efficiency, optimal base station density. I. INTRODUCTION Cell size reduction by increasing the number of macro base stations or adding tiers of low powered base stations. There are two

  17. Revamped Simulation Tool to Power Up Wave Energy Development...

    Energy Savers [EERE]

    Revamped Simulation Tool to Power Up Wave Energy Development Revamped Simulation Tool to Power Up Wave Energy Development May 21, 2015 - 2:40pm Addthis Revamped Simulation Tool to...

  18. Columbia Power Technologies, Inc. Deploys its Direct Drive Wave...

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

    Columbia Power Technologies, Inc. Deploys its Direct Drive Wave Energy Buoy Columbia Power Technologies, Inc. Deploys its Direct Drive Wave Energy Buoy April 9, 2013 - 12:00am...

  19. Density waves in the shearing sheet I. Swing amplification

    E-Print Network [OSTI]

    B. Fuchs

    2001-03-02

    The shearing sheet model of a galactic disk is studied anew. The theoretical description of its dynamics is based on three building blocks: Stellar orbits, which are described here in epicyclic approximation, the collisionless Boltzmann equation determining the distribution function of stars in phase space, and the Poisson equation in order to take account of the self-gravity of the disk. Using these tools I develop a new formalism to describe perturbations of the shearing sheet. Applying this to the unbounded shearing sheet model I demonstrate again how the disturbances of the disk evolve always into `swing amplified' density waves, i.e. spiral-arm like, shearing density enhancements, which grow and decay while the wave crests swing by from leading to trailing orientation. Several examples are given how such `swing amplification' events are incited in the shearing sheet.

  20. Design of millimeter-wave power amplifiers using InP heterojunction bipolar transistors

    E-Print Network [OSTI]

    O'Sullivan, Tomás

    2009-01-01

    3 Design of Millimeter-wave Power Cells . . . . . . . . . .4.1 Millimeter-wave Power Amplifiersetup for millimeter-wave power sweeps . . . . . . 87 Figure

  1. Traveling-wave photodetectors with high power-bandwidth and gain-bandwidth product performance

    E-Print Network [OSTI]

    2004-01-01

    TRAVELING-WAVE PHOTODETECTORS WITH HIGH POWER–BANDWIDTH ANDTraveling-wave photodetectors for high-power, largeTRAVELING-WAVE PHOTODETECTORS WITH HIGH POWER–BANDWIDTH AND

  2. Non-AbelianSU(2)gauge fields through density wave order and strain...

    Office of Scientific and Technical Information (OSTI)

    Non-AbelianSU(2)gauge fields through density wave order and strain in graphene Prev Next Title: Non-AbelianSU(2)gauge fields through density wave order and strain in graphene...

  3. Non-Abelian S U ( 2 ) gauge fields through density wave order...

    Office of Scientific and Technical Information (OSTI)

    Non-Abelian S U ( 2 ) gauge fields through density wave order and strain in graphene Prev Next Title: Non-Abelian S U ( 2 ) gauge fields through density wave order and strain...

  4. Pressure Dependence of the Charge-Density-Wave Gap in Rare-Earth...

    Office of Scientific and Technical Information (OSTI)

    Pressure Dependence of the Charge-Density-Wave Gap in Rare-Earth Tri-Tellurides Citation Details In-Document Search Title: Pressure Dependence of the Charge-Density-Wave Gap in...

  5. Radial disk heating by more than one spiral density wave

    E-Print Network [OSTI]

    I. Minchev; A. C. Quillen

    2005-10-28

    We consider a differentially rotating, 2D stellar disk perturbed by two steady state spiral density waves moving at different patterns speeds. Our investigation is based on direct numerical integration of initially circular test-particle orbits. We examine a range of spiral strengths and spiral speeds and show that stars in this time dependent gravitational field can be heated (their random motions increased). This is particularly noticeable in the simultaneous propagation of a 2-armed spiral density wave near the corotation resonance (CR), and a weak 4-armed one near the inner and outer 4:1 Lindblad resonances. In simulations with 2 spiral waves moving at different pattern speeds we find: (1) the variance of the radial velocity, sigma_R^2, exceeds the sum of the variances measured from simulations with each individual pattern; (2) sigma_R^2 can grow with time throughout the entire simulation; (3) sigma_R^2 is increased over a wider range of radii compared to that seen with one spiral pattern; (4) particles diffuse radially in real space whereas they don't when only one spiral density wave is present. Near the CR with the stronger, 2-armed pattern, test particles are observed to migrate radially. These effects take place at or near resonances of both spirals so we interpret them as the result of stochastic motions. This provides a possible new mechanism for increasing the stellar velocity dispersion in galactic disks. If multiple spiral patterns are present in the Galaxy we predict that there should be large variations in the stellar velocity dispersion as a function of radius.

  6. Disk heating by more than one spiral density wave

    E-Print Network [OSTI]

    I. Minchev; A. C. Quillen

    2005-11-01

    We consider a differentially rotating, 2D stellar disk perturbed by two steady state spiral density waves moving at different patterns speeds. Our investigation is based on direct numerical integration of initially circular test-particle orbits. We examine a range of spiral strengths and spiral speeds and show that stars in this time dependent gravitational field can be heated (their random motions increased).This is particularly noticeable in the simultaneous propagation of a 2-armed spiral density wave near the corotation resonance (CR), and a weak 4-armed one near the inner and outer 4:1 Lindblad resonances. In simulations with 2 spiral waves moving at different pattern speeds we find: (1) the variance of the radial velocity, sigma_R^2, exceeds the sum of the variances measured from simulations with each individual pattern; (2) sigma_R^2 can grow with time throughout the entire simulation; (3) sigma_R^2 is increased over a wider range of radii compared to that seen with one spiral pattern; (4) particles diffuse radially in real space whereas they don't when only one spiral density wave is present. Near the CR with the stronger, 2-armed pattern, test particles are observed to migrate radially. These effects take place at or near resonances of both spirals so we interpret them as the result of stochastic motions. This provides a possible new mechanism for increasing the stellar velocity dispersion in galactic disks. If multiple spiral patterns are present in the Galaxy we predict that there should be large variations in the stellar velocity dispersion as a function of radius.

  7. NO FLARES FROM GAMMA-RAY BURST AFTERGLOW BLAST WAVES ENCOUNTERING SUDDEN CIRCUMBURST DENSITY CHANGE

    SciTech Connect (OSTI)

    Gat, Ilana; Van Eerten, Hendrik; MacFadyen, Andrew [Center for Cosmology and Particle Physics, Physics Department, New York University, New York, NY 10003 (United States)

    2013-08-10

    Afterglows of gamma-ray bursts are observed to produce light curves with the flux following power-law evolution in time. However, recent observations reveal bright flares at times on the order of minutes to days. One proposed explanation for these flares is the interaction of a relativistic blast wave with a circumburst density transition. In this paper, we model this type of interaction computationally in one and two dimensions, using a relativistic hydrodynamics code with adaptive mesh refinement called RAM, and analytically in one dimension. We simulate a blast wave traveling in a stellar wind environment that encounters a sudden change in density, followed by a homogeneous medium, and compute the observed radiation using a synchrotron model. We show that flares are not observable for an encounter with a sudden density increase, such as a wind termination shock, nor for an encounter with a sudden density decrease. Furthermore, by extending our analysis to two dimensions, we are able to resolve the spreading, collimation, and edge effects of the blast wave as it encounters the change in circumburst medium. In all cases considered in this paper, we find that a flare will not be observed for any of the density changes studied.

  8. High power density supercapacitors using locally aligned carbon nanotube electrodes

    E-Print Network [OSTI]

    Du, C S; Yeh, J; Pan, Ning

    2005-01-01

    carbon nanotubes in 1 ml of DMF) on two 12 mm × 12 mm nickelnanotubes as electrodes. An [7, 15] obtained high power density with polished nickel

  9. Spatiotemporal evolution of dielectric driven cogenerated dust density waves

    SciTech Connect (OSTI)

    Sarkar, Sanjib; Bose, M. [Department of Physics, Jadavpur University, Kolkata 700032 (India)] [Department of Physics, Jadavpur University, Kolkata 700032 (India); Mukherjee, S. [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India)] [FCIPT, Institute for Plasma Research, Gandhinagar 382428 (India); Pramanik, J. [Kharagpur College, Kharagpur 721305, West Bengal (India)] [Kharagpur College, Kharagpur 721305, West Bengal (India)

    2013-06-15

    An experimental observation of spatiotemporal evolution of dust density waves (DDWs) in cogenerated dusty plasma in the presence of modified field induced by glass plate is reported. Various DDWs, such as vertical, oblique, and stationary, were detected simultaneously for the first time. Evolution of spatiotemporal complexity like bifurcation in propagating wavefronts is also observed. As dust concentration reaches extremely high value, the DDW collapses. Also, the oblique and nonpropagating mode vanishes when we increase the number of glass plates, while dust particles were trapped above each glass plates showing only vertical DDWs.

  10. Charge density wave in hydrogen at high pressure

    E-Print Network [OSTI]

    Magdau, Ioan B

    2015-01-01

    We present extensive molecular dynamics (MD) simulations investigating numerous candidate crystal structures for hydrogen in conditions around the present experimental frontier (400GPa). Spontaneous phase transitions in the simulations reveal a new structure candidate comprising twofold coordinated chains of hydrogen atoms. We explain the electronic structure of this phase in terms of a charge density wave and calculate its experimental signature. In detailed tests of the accuracy of our calculation, we find that k-point sampling is far more important in MD than in static calculations, because of the freedom it give the atoms to rearrange themselves optimally for the given sampling.

  11. Radio-wave propagation through a medium containing electron-density fluctuations described by an anisotropic Goldreich-Sridhar spectrum

    E-Print Network [OSTI]

    B. D. G. Chandran; D. C. Backer

    2002-02-13

    We study the propagation of radio waves through a medium possessing density fluctuations that are elongated along the ambient magnetic field and described by an anisotropic Goldreich-Sridhar power spectrum. We derive general formulas for the wave phase structure function, visibility, angular broadening, diffraction-pattern length scales, and scintillation time scale for arbitrary distributions of turbulence along the line of sight, and specialize these formulas to idealized cases.

  12. WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01

    case, the electrons have negative wave energy for 2w ne w wave energy for 2w .w > 0 nl Hence, unstable waves with negative phase velocity,

  13. High Power Superconducting Continuous Wave Linacs for Protons...

    Office of Science (SC) Website

    Power Superconducting Continuous Wave Linacs for Protons and Heavy-Ions Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of...

  14. Reaction force control implementation of a linear generator in irregular waves for a wave power system 

    E-Print Network [OSTI]

    Li, Bin

    2012-11-29

    Most designs for wave energy converters include a hydraulic (or pneumatic) interface between the wave device and the generator to smooth electricity production, but a direct drive power take-off system is a possible way ...

  15. Evidence against a charge density wave on Bi(111)

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

    Kim, T. K.; Wells, J.; Kirkegaard, C.; Li, Z.; Hoffmann, S. V.; Gayone, J. E.; Fernandez-Torrente, I.; Häberle, P.; Pascual, J. I.; Moore, K. T.; et al

    2005-08-18

    The Bi(111) surface was studied by scanning tunneling microscopy (STM), transmission electron microscopy (TEM) and angle-resolved photoemission (ARPES) in order to verify the existence of a recently proposed surface charge density wave (CDW). The STM and TEM results to not support a CDW scenario at low temperatures. Thus the quasiparticle interference pattern observed in STM confirms the spin-orbit split character of the surface states which prevents the formation of a CDW, even in the case of good nesting. The dispersion of the electronic states observed with ARPES agrees well with earlier findings. In particular, the Fermi contour of the electronmore »pocket at the centre of the surface Brillouin zone is found to have a hexagonal shape. However, no gap opening or other signatures of a CDW phase transition can be found in the temperature-dependent data.« less

  16. Design, characterization, and modeling of GaN based HFETs for millimeter wave and microwave power amplifier applications

    E-Print Network [OSTI]

    Conway, Adam M.

    2006-01-01

    for Microwave and Millimeter-Wave Power Applications,” IEDM.power microwave and millimeter wave power amplifiers. Whilemicrowave and millimeter- wave power amplifier applications.

  17. Demonstration of Josephson effect submillimeter wave sources with increased power

    E-Print Network [OSTI]

    Han, Siyuan; Bi, Baokang; Zhang, Wenxing; Lukens, J. E.

    1994-03-05

    A submillimeter wave source based on a new design using Josephson junction arrays has been developed and tested. The maximum rf power, delivered to a 68? load and detected on chip, was 47 ?W at 394 GHz. Significant power ...

  18. Design of millimeter-wave power amplifiers using InP heterojunction bipolar transistors

    E-Print Network [OSTI]

    O'Sullivan, Tomás

    2009-01-01

    for Cascode Power Cells . . . . . . . . . . . . . .3 Design of Millimeter-wave Power Cells . . . . . . . . . .Millimeter-wave Cascode Power Cell Design . . . . . 5.1.3

  19. Wave Power Resources off the Hawaiian Islands luisvega@hawaii.edu Wave Resources for Representative Sites Around the Hawaiian Islands

    E-Print Network [OSTI]

    Wave Power Resources off the Hawaiian Islands luisvega@hawaii.edu 1 Wave Resources for Representative Sites Around the Hawaiian Islands Table of Contents Summary p2 Background: Wave Power Conversion p3 Licensing and Permitting p3 Challenges and Barriers p4 Wave Power Resources: Previous Work p5 Wave

  20. An evolutionary fuel assembly design for high power density BWRs

    E-Print Network [OSTI]

    Karahan, Aydin

    2007-01-01

    An evolutionary BWR fuel assembly design was studied as a means to increase the power density of current and future BWR cores. The new assembly concept is based on replacing four traditional assemblies and large water gap ...

  1. The design of high power density annular fuel for LWRs

    E-Print Network [OSTI]

    Yuan, Yi, 1975-

    2004-01-01

    Fuel performance models have been developed to assess the performance of internally and externally cooled LWR annular fuel. Such fuel may be operated at 30-50% higher core power density than the current operating LWRs, and ...

  2. New approximate radial wave functions for power-law potentials

    E-Print Network [OSTI]

    Vladimir Kudryashov

    2007-09-26

    Radial wave functions for power-law potentials are approximated with the help of power-law substitution and explicit summation of the leading constituent WKB series. Our approach reproduces the correct behavior of the wave functions at the origin, at the turning points and far away from the turning points

  3. WAVE-ENERGY DENSITY AND WAVE-MOMENTUM DENSITY OF EACH SPECIES OF A COLLISION-LESS PLASMA

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01

    case, the electrons have negative wave energy for 2w ne w wave energy for 2w . > w > 0 nlw/k to the negative wave energy of the electrons. positive

  4. No evidence for the blue-tilted power spectrum of relic gravitational waves

    E-Print Network [OSTI]

    Qing-Guo Huang; Sai Wang

    2015-02-09

    In this paper, we constrain the tilt of the power spectrum of relic gravitational waves by combining the data from BICEP2/Keck array and Planck (BKP) and the Laser Interferometer Gravitational-Waves Observatory (LIGO). From the data of BKP B-modes, the constraint on the tensor tilt is $n_t=0.66^{+1.83}_{-1.44}$ at the $68%$ confidence level. By further adding the LIGO upper limit on the energy density of gravitational waves, the constraint becomes $n_t=-0.76^{+1.37}_{-0.52}$ at the $68%$ confidence level. We conclude that there is no evidence for a blue-tilted power spectrum of relic gravitational waves and either sign of the index of tensor power spectrum is compatible with the data.

  5. Enhanced surfaces lead to increased heat transfer and power density.

    E-Print Network [OSTI]

    be used by electric motors. Aggressive ther- mal management is essential in boosting power density. The National Renewable Energy Laboratory's (NREL's) Advanced Power Electronics Task in the Center components. It is estimated that improved thermal performance can reduce the number or area of the insulated

  6. On the Power Spectrum Density of Gamma Ray Bursts

    E-Print Network [OSTI]

    Motoko Suzuki; Masahiro Morikawa; Izumi Joichi

    2001-04-13

    Gamma ray bursts (GRBs) are known to have short-time variability and power-law behavior with the index -1.67 in the power spectrum density. Reanalyzing the expanded data, we have found a) the power-law comes from the global profile of the burst and not from the self-similar shots nor rapid fluctuations in the luminosity profile. b) The power indices vary from burst to burst and the value -1.67 is given simply as the mean value of the distribution; there is no systematic correlation among GRBs to yield the power law.

  7. FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities

    E-Print Network [OSTI]

    Strangeway, Robert J.

    FAST observations of VLF waves in the auroral zone: Evidence of very low plasma densities R. J. Peterson,6 E. G. Shelley,6 and R. F. Pfaff,7 Abstract. The Fast Auroral SnapshoT (FAST) explorer frequently-form data acquired by FAST within the auroral density cavity show clear signatures of whistler-mode waves

  8. IMAGING WITH DIFFUSE PHOTON DENSITY WAVES Maureen A. O'Leary

    E-Print Network [OSTI]

    IMAGING WITH DIFFUSE PHOTON DENSITY WAVES Maureen A. O'Leary A DISSERTATION in PHYSICS Presented Chairperson #12;COPYRIGHT Maureen Ann O'Leary 1996 #12;DEDICATION This work is dedicated to Mom, Dad, Terry v without David's support. #12;ABSTRACT IMAGING WITH DIFFUSE PHOTON DENSITY WAVES Maureen A. O'Leary

  9. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    Power Maximization in Wave-Energy Converters Using Sampled-design optimization of wave energy converters con- sistingN. Sahinkaya. A review of wave energy converter technology.

  10. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    with controlled motion. Power from sea waves, pages 381–399,SAN DIEGO Power Maximization in Wave-Energy Converters Usingfor wave energy con- verters with limited power takeoff

  11. Protective, Modular Wave Power Generation System

    SciTech Connect (OSTI)

    Vvedensky, Jane M.; Park, Robert Y.

    2012-11-27

    The concept of small wave energy conversion modules that can be built into large, scalable arrays, in the same vein as solar panels, has been developed. This innovation lends itself to an organic business and development model, and enables the use of large-run manufacturing technology to reduce system costs. The first prototype module has been built to full-scale, and tested in a laboratory wave channel. The device has been shown to generate electricity and dissipate wave energy. Improvements need to be made to the electrical generator and a demonstration of an array of modules should be made in natural conditions.

  12. Inferring Magnetospheric Heavy Ion Density using EMIC Waves

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Kim, Hyomin; Lee, Dong-Hun

    2014-05-01

    We present a method to infer heavy ion concentration ratios from EMIC wave observations that result from ionion hybrid (IIH) resonance. A key feature of the ion-ion hybrid resonance is the concentration of wave energy in a field-aligned resonant mode that exhibits linear polarization. This mode converted wave is localized at the location where the frequency of a compressional wave driver matches the IIH resonance condition, which depends sensitively on the heavy ion concentration. This dependence makes it possible to estimate the heavy ion concentration ratio. In this letter, we evaluate the absorption coefficients at the IIH resonance at Earth's geosynchronous orbit for variable concentrations of He+ and field-aligned wave numbers using a dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentrations, it only occurs for a limited range of field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Using the wave absorption and observed EMIC waves from GOES-12 satellite, we demonstrate how this technique can be used to estimate that the He+ concentration is around 4% near L = 6.6.

  13. Limits to the power density of very large wind farms

    E-Print Network [OSTI]

    Nishino, Takafumi

    2013-01-01

    A simple analysis is presented concerning an upper limit of the power density (power per unit land area) of a very large wind farm located at the bottom of a fully developed boundary layer. The analysis suggests that the limit of the power density is about 0.38 times $\\tau_{w0}U_{F0}$, where $\\tau_{w0}$ is the natural shear stress on the ground (that is observed before constructing the wind farm) and $U_{F0}$ is the natural or undisturbed wind speed averaged across the height of the farm to be constructed. Importantly, this implies that the maximum extractable power from such a very large wind farm will not be proportional to the cubic of the wind speed at the farm height, or even the farm height itself, but be proportional to $U_{F0}$.

  14. Density waves in the shearing sheet IV. Interaction with a live dark halo

    E-Print Network [OSTI]

    B. Fuchs

    2004-03-01

    It is shown that if the self-gravitating shearing sheet, a model of a patch of a galactic disk, is embedded in a live dark halo, this has a strong effect on the dynamics of density waves in the sheet. I describe how the density waves and the halo interact via halo particles either on orbits in resonance with the wave or on non-resonant orbits. Contrary to expectation the presence of the halo leads to a very considerable enhancement of the amplitudes of the density waves in the shearing sheet. This effect appears to be the equivalent of the recently reported enhanced growth of bars in numerically simulated stellar disks embedded in live dark halos. Finally I discuss the transfer of linear momentum from a density wave in the sheet to the halo and show that it is mediated only by halo particles on resonant orbits.

  15. High-Power Density Target Design and Analyses for Accelerator

    E-Print Network [OSTI]

    McDonald, Kirk

    capacity limits applicability ­ Water · Low boiling point must account for twophase flow · CorrosionHigh-Power Density Target Design and Analyses for Accelerator Production of Isotopes W. David Intensity Proton Accelerators Fermi National Accelerator Laboratory October 20, 2009 #12;Outline Purpose

  16. High Power Millimeter-Wave Signal Generation in Advanced SiGe and CMOS Process

    E-Print Network [OSTI]

    Lin, Hsin-Chang

    2015-01-01

    1.3 Millimeter-Wave Signal Generation 1.4 ThesisPower Millimeter-Wave Signal Generation in Advanced SiGe andPower Millimeter-Wave Signal Generation in Advanced SiGe and

  17. High Power Millimeter-Wave Signal Generation in Advanced SiGe and CMOS Process

    E-Print Network [OSTI]

    Lin, Hsin-Chang

    2015-01-01

    1.1 Millimeter-Wave Applications . . . 1.2 PowerTechniques . . . 1.3 Millimeter-Wave Signal Generation 1.4High-Power Millimeter-Wave Frequency Multipliers in Advance

  18. A Low-Power System Design for Lamb Wave Methods Shaver Deyerlea

    E-Print Network [OSTI]

    Ha, Dong S.

    A Low-Power System Design for Lamb Wave Methods Shaver Deyerlea , Dong Sam Haa , and Daniel J significantly reduce the overall power dissipation of a Lamb wave system. In this paper, we propose a method damage on aluminum plates. Keywords: Low power SHM system, Low power Lamb wave system, Lamb Wave, Analog

  19. Creation of nonlinear density gradients for use in internal wave research

    E-Print Network [OSTI]

    Harris, Victoria Siân

    2007-01-01

    A method was developed to create a nonlinear density gradient in a tank of water. Such gradients are useful for studying internal waves, an ocean phenomenon that plays an important role in climate and ocean circulation. ...

  20. Interaction of waves in a two-layer density stratified fluid

    E-Print Network [OSTI]

    Alam, Mohammad-Reza

    2008-01-01

    In the first part of this thesis, the mechanisms of nonlinear resonant interaction of surface-interfacial waves with a rippled bottom in a two-layer density stratified fluid in two dimensions is investigated via perturbation ...

  1. X-Ray Diffraction Observations of a Charge-Density-Wave Order...

    Office of Scientific and Technical Information (OSTI)

    X-Ray Diffraction Observations of a Charge-Density-Wave Order in Superconducting Ortho-II YBa2Cu3O6.54 Single Crystals in Zero Magnetic Field Citation Details In-Document Search...

  2. Pressure Dependence of the Charge-Density-Wave Gap in Rare-Earth...

    Office of Scientific and Technical Information (OSTI)

    of the optical properties of CeTesub 3, which exhibits an incommensurate charge-density-wave (CDW) state already at 300 K. Our data are collected in the mid-infrared spectral...

  3. Method of measuring reactive acoustic power density in a fluid

    DOE Patents [OSTI]

    Wheatley, J.C.; Swift, G.W.; Migliori, A.

    1985-09-03

    A method for determining reactive acoustic power density level and its direction in a fluid using a single sensor is disclosed. In the preferred embodiment, an apparatus for conducting the method, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas. 5 figs.

  4. Method of measuring reactive acoustic power density in a fluid

    SciTech Connect (OSTI)

    Wheatley, John C.; Swift, Gregory W.; Migliori, Albert

    1985-01-01

    A method for determining reactive acoustic power density level and its direction in a fluid using a single sensor is disclosed. In the preferred embodiment, an apparatus for conducting the method, which is termed a thermoacoustic couple, consists of a stack of thin, spaced apart polymeric plates, selected ones of which include multiple bimetallic thermocouple junctions positioned along opposite end edges thereof. The thermocouple junctions are connected in series in the nature of a thermopile, and are arranged so as to be responsive to small temperature differences between the opposite edges of the plates. The magnitude of the temperature difference, as represented by the magnitude of the electrical potential difference generated by the thermopile, is found to be directly related to the level of acoustic power density in the gas.

  5. Electrojet-independent ionospheric extremely low frequency/very low frequency wave generation by powerful high frequency waves

    SciTech Connect (OSTI)

    Kuo, Spencer; Snyder, Arnold; Chang, Chia-Lie

    2010-08-15

    Results of extremely low frequency/very low frequency (ELF/VLF) wave generation by intensity-modulated high frequency (HF) heaters of 3.2 MHz in Gakona, Alaska, near local solar noon during a geomagnetic quiet time, are presented to support an electrojet-independent ELF/VLF wave generation mechanism. The modulation was set by splitting the HF transmitter array into two subarrays; one was run at cw full power and the other run alternatively at 50% and 100% power modulation by rectangular waves of 2.02, 5, 8, and 13 kHz. The most effective generation was from the X-mode heater with 100% modulation. While the 8 kHz radiation has the largest wave amplitude, the spectral intensity of the radiation increases with the modulation frequency, i.e., 13 kHz line is the strongest. Ionograms recorded significant virtual height spread of the O-mode sounding echoes. The patterns of the spreads and the changes of the second and third hop virtual height traces caused by the O/X-mode heaters are distinctively different, evidencing that it is due to differently polarized density irregularities generated by the filamentation instability of the O/X-mode HF heaters.

  6. Gravitational wave generation in power-law inflationary models

    E-Print Network [OSTI]

    Paulo M. Sá; Alfredo B. Henriques

    2008-06-06

    We investigate the generation of gravitational waves in power-law inflationary models. The energy spectrum of the gravitational waves is calculated using the method of continuous Bogoliubov coefficients. We show that, by looking at the interval of frequencies between 10^(-5) and 10^5 Hz and also at the GHz range, important information can be obtained, both about the inflationary period itself and about the thermalization regime between the end of inflation and the beginning of the radiation-dominated era. We thus deem the development of gravitational wave detectors, covering the MHz/GHz range of frequencies, to be an important task for the future.

  7. Power and polarization monitor development for high power millimeter-wave

    SciTech Connect (OSTI)

    Makino, R., E-mail: makino.ryohhei@ms.nifs.ac.jp; Kobayashi, K. [Department of Energy Engineering and Science, Nagoya University, Nagoya 464-8603 (Japan); Kubo, S. [Department of Energy Engineering and Science, Nagoya University, Nagoya 464-8603 (Japan); National Institute for Fusion Science, Toki 509-5292 (Japan); Kobayashi, S.; Shimozuma, T.; Yoshimura, Y.; Igami, H.; Takahashi, H.; Mutoh, T. [National Institute for Fusion Science, Toki 509-5292 (Japan)

    2014-11-15

    A new type monitor of power and polarization states of millimeter-waves has been developed to be installed at a miter-bend, which is a part of transmission lines of millimeter-waves, for electron cyclotron resonance heating on the Large Helical Device. The monitor measures amplitudes and phase difference of the electric field of the two orthogonal polarizations which are needed for calculation of the power and polarization states of waves. The power and phase differences of two orthogonal polarizations were successfully detected simultaneously.

  8. Power supply switching for a mm-wave asymmetric multilevel outphasing power amplifier system

    E-Print Network [OSTI]

    Spaulding, Jonathon David

    2010-01-01

    This thesis demonstrates power switches to be used in our new Asymmetric Multilevel Outphasing (AMO) transmitter architecture at mm-wave frequencies. The AMO topology breaks the linearity vs. efficiency design objective ...

  9. ALPHA POWER CHANNELLING WITH TWO WAVES N.J. FISCH, M.C. HERRMANN

    E-Print Network [OSTI]

    ALPHA POWER CHANNELLING WITH TWO WAVES N.J. FISCH, M.C. HERRMANN Princeton Plasma Physics of waves, rather than by one wave alone. While one wave constrains more firmly the direction of the energy transfer, the necessary wave characteristics are far more easily achieved through a combination of waves

  10. Advanced, High Power, Next Scale, Wave Energy Conversion Device

    SciTech Connect (OSTI)

    Mekhiche, Mike; Dufera, Hiz; Montagna, Deb

    2012-10-29

    The project conducted under DOE contract DE?EE0002649 is defined as the Advanced, High Power, Next Scale, Wave Energy Converter. The overall project is split into a seven?stage, gated development program. The work conducted under the DOE contract is OPT Stage Gate III work and a portion of Stage Gate IV work of the seven stage product development process. The project effort includes Full Concept Design & Prototype Assembly Testing building on our existing PowerBuoy? technology to deliver a device with much increased power delivery. Scaling?up from 150kW to 500kW power generating capacity required changes in the PowerBuoy design that addressed cost reduction and mass manufacturing by implementing a Design for Manufacturing (DFM) approach. The design changes also focused on reducing PowerBuoy Installation, Operation and Maintenance (IO&M) costs which are essential to reducing the overall cost of energy. In this design, changes to the core PowerBuoy technology were implemented to increase capability and reduce both CAPEX and OPEX costs. OPT conceptually envisaged moving from a floating structure to a seabed structure. The design change from a floating structure to seabed structure would provide the implementation of stroke? unlimited Power Take?Off (PTO) which has a potential to provide significant power delivery improvement and transform the wave energy industry if proven feasible.

  11. Surface acoustic wave propagation and inhomogeneities in low-density two-dimensional electron systems near the metalinsulator transition

    E-Print Network [OSTI]

    Eisenstein, Jim

    Surface acoustic wave propagation and inhomogeneities in low-density two-dimensional electron) in a low-density regime (!1010 cmK2 ) at zero magnetic field. The interaction of the surface acoustic wave systems; D. Metal­insulator transition; E. Surface acoustic waves The apparent metal­insulator transition

  12. Constraining the gravitational wave energy density of the Universe using Earth's ring

    E-Print Network [OSTI]

    Michael Coughlin; Jan Harms

    2014-06-04

    The search for gravitational waves is one of today's major scientific endeavors. A gravitational wave can interact with matter by exciting vibrations of elastic bodies. Earth itself is a large elastic body whose so-called normal-mode oscillations ring up when a gravitational wave passes. Therefore, precise measurement of vibration amplitudes can be used to search for the elusive gravitational-wave signals. Earth's free oscillations that can be observed after high-magnitude earthquakes have been studied extensively with gravimeters and low-frequency seismometers over many decades leading to invaluable insight into Earth's structure. Making use of our detailed understanding of Earth's normal modes, numerical models are employed for the first time to accurately calculate Earth's gravitational-wave response, and thereby turn a network of sensors that so far has served to improve our understanding of Earth, into an astrophysical observatory exploring our Universe. In this article, we constrain the energy density of gravitational waves to values in the range 0.035 - 0.15 normalized by the critical energy density of the Universe at frequencies between 0.3mHz and 5mHz, using 10 years of data from the gravimeter network of the Global Geodynamics Project that continuously monitors Earth's oscillations. This work is the first step towards a systematic investigation of the sensitivity of gravimeter networks to gravitational waves. Further advance in gravimeter technology could improve sensitivity of these networks and possibly lead to gravitational-wave detection.

  13. Field induced spin density wave and spiral phases in a layered antiferromagnet

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

    Stone, Matthew B.; Lumsden, Mark D.; Garlea, Vasile O.; Grenier, B.; Ressouche, E.; Samulon, Eric C.; Fisher, Ian R.

    2015-07-28

    We determine the low-field ordered magnetic phases of the S=1 dimerized antiferromagnet Ba3Mn2O8 using single crystal neutron diffraction. We find that for magnetic fields between ?0H=8.80 T and 10.56 T applied along the [1\\bar{1}0] direction the system exhibits spin density wave order with incommensurate wave vectors of type (?,?,?). For ?0H > 10.56 T, the magnetic order changes to a spiral phase with incommensurate wave vectors only along the [hh0] direction. For both field induced ordered phases, the magnetic moments are lying in the plane perpendicular to the field direction. The nature of these two transitions is fundamentally different: themore »low-field transition is a second order transition to a spin-density wave ground state, while the one at higher field, toward the spiral phase, is of first order.« less

  14. Innovative Wave Power Device Starts Producing Clean Power in Hawaii |

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACT EVALUATION PLAN FOR0987PEnergy Software TacklesDepartment of

  15. Constraining the gravitational wave energy density of the Universe using Earth's ring

    E-Print Network [OSTI]

    Coughlin, Michael

    2014-01-01

    The search for gravitational waves is one of today's major scientific endeavors. A gravitational wave can interact with matter by exciting vibrations of elastic bodies. Earth itself is a large elastic body whose so-called normal-mode oscillations ring up when a gravitational wave passes. Therefore, precise measurement of vibration amplitudes can be used to search for the elusive gravitational-wave signals. Earth's free oscillations that can be observed after high-magnitude earthquakes have been studied extensively with gravimeters and low-frequency seismometers over many decades leading to invaluable insight into Earth's structure. Making use of our detailed understanding of Earth's normal modes, numerical models are employed for the first time to accurately calculate Earth's gravitational-wave response, and thereby turn a network of sensors that so far has served to improve our understanding of Earth, into an astrophysical observatory exploring our Universe. In this article, we constrain the energy density o...

  16. Alpha Power Channeling with Two Waves N. J. Fisch and M. C. Herrmann

    E-Print Network [OSTI]

    Alpha Power Channeling with Two Waves N. J. Fisch and M. C. Herrmann Princeton Plasma Physics is likely to be realized only through the excitation of a variety of waves, rather than by one wave alone. While one wave constrains more firmly the direction of the energy transfer, the necessary wave

  17. A powerful reflector in relativistic backward wave oscillator

    SciTech Connect (OSTI)

    Cao, Yibing, E-mail: caoyibing@nint.ac.cn; Sun, Jun; Teng, Yan; Zhang, Yuchuan; Zhang, Lijun; Shi, Yanchao; Ye, Hu; Chen, Changhua [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an, Shaanxi 710024 (China)

    2014-09-15

    An improved TM{sub 021} resonant reflector is put forward. Similarly with most of the slow wave structures used in relativistic backward wave oscillator, the section plane of the proposed reflector is designed to be trapezoidal. Compared with the rectangular TM{sub 021} resonant reflector, such a structure can depress RF breakdown more effectively by weakening the localized field convergence and realizing good electrostatic insulation. As shown in the high power microwave (HPM) generation experiments, with almost the same output power obtained by the previous structure, the improved structure can increase the pulse width from 25?ns to over 27?ns and no obvious surface damage is observed even if the generated HPM pulses exceed 1000 shots.

  18. Entropic uncertainty relation for power-law wave packets

    E-Print Network [OSTI]

    Sumiyoshi Abe; S. Martinez; F. Pennini; A. Plastino

    2002-06-06

    For the power-law quantum wave packet in configuration space, the variance of the position observable may be divergent. Accordingly, the information-entropic formulation of the uncertainty principle becomes more appropriate than the Heisenberg-type formulation, since it involves only the finite quantities. It is found that the total amount of entropic uncertainty converges to its lower bound in the limit of a large value of the exponent.

  19. Rigorous Analysis of Traveling Wave Photodetectors under High-Power Illumination

    E-Print Network [OSTI]

    Aste, Andreas

    Rigorous Analysis of Traveling Wave Photodetectors under High- Power Illumination Damir Pasalic data has shown excellent agreement. I. INTRODUCTION High-power traveling-wave photodetectors (TWPDs and velocity mismatch between the optical and RF waves over the length of the TWPD. For high power handling

  20. Electromagnetic Wave Power Observed Near the Moon during Terrestrial Bow Shock Crossings

    E-Print Network [OSTI]

    Fillingim, Matthew

    Electromagnetic Wave Power Observed Near the Moon during Terrestrial Bow Shock Crossings and Its (?) noise (cf. Nakagawa et al., 2011) 3. Large increase in magnetic field strength and wave power at the bow are evident in the plasma and magnetic field data Increase in wave power over a broad range of f i t h i p

  1. Alpha power channeling using ion-Bernstein waves* N. J. Fischtna)

    E-Print Network [OSTI]

    Alpha power channeling using ion-Bernstein waves* N. J. Fischtna) Princeton Plasma Physics of this power. The mechanism of channeling relies upon the amplifica- tion of a wave at the expense of the a must not require too large a power input. The rapid slowing down by the wave ensures that the a

  2. Proc 12th conf. RF Power in Plasmas, Savannah, 1997 Ion-Bernstein Wave Mode Conversion

    E-Print Network [OSTI]

    Jaun, André

    Proc 12th conf. RF Power in Plasmas, Savannah, 1997 Ion-Bernstein Wave Mode Conversion in Hot-Bernstein wave can dramatically affect the power profile and partition among the species. The results obtained very different wavelengths. Where the spa- tial scale of two waves match, the power associated with one

  3. CENTER FOR PULSED POWER DRIVEN HIGH ENERGY DENSITY PLASMA STUDIES

    SciTech Connect (OSTI)

    Professor Bruce R. Kusse; Professor David A. Hammer

    2007-04-18

    This annual report summarizes the activities of the Cornell Center for Pulsed-Power-Driven High-Energy-Density Plasma Studies, for the 12-month period October 1, 2005-September 30, 2006. This period corresponds to the first year of the two-year extension (awarded in October, 2005) to the original 3-year NNSA/DOE Cooperative Agreement with Cornell, DE-FC03-02NA00057. As such, the period covered in this report also corresponds to the fourth year of the (now) 5-year term of the Cooperative Agreement. The participants, in addition to Cornell University, include Imperial College, London (IC), the University of Nevada, Reno (UNR), the University of Rochester (UR), the Weizmann Institute of Science (WSI), and the P.N. Lebedev Physical Institute (LPI), Moscow. A listing of all faculty, technical staff and students, both graduate and undergraduate, who participated in Center research activities during the year in question is given in Appendix A.

  4. Measurement of Electron Density near Plasma Grid of Large-scaled Negative Ion Source by Means of Millimeter-Wave Interferometer

    SciTech Connect (OSTI)

    Nagaoka, K.; Tokuzawa, T.; Tsumori, K.; Nakano, H.; Ito, Y.; Osakabe, M.; Ikeda, K.; Kisaki, M.; Shibuya, M.; Sato, M.; Komada, S.; Kondo, T.; Hayashi, H.; Asano, E.; Takeiri, Y.; Kaneko, O.

    2011-09-26

    A millimeter-wave interferometer with the frequency of 39 GHz ({lambda} 7.7 mm) was newly installed to a large-scaled negative ion source. The measurable line-integrated electron density (n{sub e}l) is from 2x10{sup 16} to 7x10{sup 18} m{sup -2}, where n{sub e} and l represent an electron density and the plasma length along the millimeter-wave path, respectively. Our interest in this study is behavior of negative ions and reduction of electron density in the beam extraction region near the plasma grid. The first results show the possibility of the electron density measurement by the millimeter-wave interferometer in this region. The line-averaged electron density increases proportional to the arc power under the condition without cesium seeding. The significant decrease of the electron density and significant increase of the negative ion density were observed just after the cesium seeding. The electron density measured with the interferometer agrees well with that observed with a Langmuir probe. The very high negative ion ratio of n{sub H-}/(n{sub e}+n{sub H-}) = 0.85 was achieved within 400 min. after the cesium seeding.

  5. The response of plasma density to breaking inertial gravity wave in the lower regions of ionosphere

    SciTech Connect (OSTI)

    Tang, Wenbo Mahalov, Alex

    2014-04-15

    We present a three-dimensional numerical study for the E and lower F region ionosphere coupled with the neutral atmosphere dynamics. This model is developed based on a previous ionospheric model that examines the transport patterns of plasma density given a prescribed neutral atmospheric flow. Inclusion of neutral dynamics in the model allows us to examine the charge-neutral interactions over the full evolution cycle of an inertial gravity wave when the background flow spins up from rest, saturates and eventually breaks. Using Lagrangian analyses, we show the mixing patterns of the ionospheric responses and the formation of ionospheric layers. The corresponding plasma density in this flow develops complex wave structures and small-scale patches during the gravity wave breaking event.

  6. Luther-Emery Phase and Atomic-Density Waves in a Trapped Fermion Gas

    SciTech Connect (OSTI)

    Gao Xianlong; Rizzi, M.; Polini, Marco; Tosi, M. P.; Fazio, Rosario; Campo, V. L. Jr.; Capelle, K.

    2007-01-19

    The Luther-Emery liquid is a state of matter that is predicted to occur in one-dimensional systems of interacting fermions and is characterized by a gapless charge spectrum and a gapped spin spectrum. In this Letter we discuss a realization of the Luther-Emery phase in a trapped cold-atom gas. We study by means of the density-matrix renormalization-group technique a two-component atomic Fermi gas with attractive interactions subject to parabolic trapping inside an optical lattice. We demonstrate how this system exhibits compound phases characterized by the coexistence of spin pairing and atomic-density waves. A smooth crossover occurs with increasing magnitude of the atom-atom attraction to a state in which tightly bound spin-singlet dimers occupy the center of the trap. The existence of atomic-density waves could be detected in the elastic contribution to the light-scattering diffraction pattern.

  7. Brain Tissue Depth (mm) LightPowerDensity(mW/mm2

    E-Print Network [OSTI]

    Schnitzer, Mark

    Brain Tissue Depth (mm) LightPowerDensity(mW/mm2 ) Power Meter Tissue block Bare Fiber = 12° = 6 with the beveled cannula over CeA. d) Chart indicating estimated light power density seen at various distances from the fiber tip in mouse brain tissue when the light power density seen at the fiber tip was 7 mW (~99 mW/mm2

  8. Nonlinear Power Spectral Densities for the Harmonic Oscillator

    E-Print Network [OSTI]

    B. D. Hauer; J. Maciejko; J. P. Davis

    2015-06-13

    In this paper, we discuss a general procedure by which nonlinear power spectral densities (PSDs) of the harmonic oscillator can be calculated in both the quantum and classical regimes. We begin with an introduction of the damped and undamped classical harmonic oscillator, followed by an overview of the quantum mechanical description of this system. A brief review of both the classical and quantum autocorrelation functions (ACFs) and PSDs follow. We then introduce a general method by which the kth-order PSD for the harmonic oscillator can be calculated, where $k$ is any positive integer. This formulation is verified by first reproducing the known results for the $k = 1$ case of the linear PSD. It is then extended to calculate the second-order PSD, useful in the field of quantum measurement, corresponding to the $k = 2$ case of the generalized method. In this process, damping is included into each of the quantum linear and quadratic PSDs, producing realistic models for the PSDs found in experiment. These quantum PSDs are shown to obey the correspondence principle by matching with what was calculated for their classical counterparts in the high temperature, high-Q limit. Finally, we demonstrate that our results can be reproduced using the fluctuation-dissipation theorem, providing an independent check of our resultant PSDs.

  9. High power densities from high-temperature material interactions

    SciTech Connect (OSTI)

    Morris, J.F.

    1981-01-01

    Thermionic energy conversion (TEC) and metallic-fluid heat pipes (MFHPs) offer important and unique advantages in terrestrial and space energy processing. And they are well suited to serve together synergistically. TEC and MFHPs operate through working-fluid vaporization, condensation cycles that accept great thermal power densities at high temperatures. TEC and MFHPs have apparently simple, isolated performance mechanisms that are somewhat similar. And they also have obviously difficult, complected material problems that again are somewhat similar. Intensive investigation reveals that aspects of their operating cycles and material problems tend to merge: high-temperature material effects determine the level and lifetime of performance. Simplified equations verify the preceding statement for TEC and MFHPs. Material properties and interactions exert primary influences on operational effectiveness. And thermophysicochemical stabilities dictate operating temperatures which regulate the thermoemissive currents of TEC and the vaporization flow rates of MFHPs. Major high-temperature material problems of TEC and MFHPs have been solved. These solutions lead to productive, cost-effective applications of current TEC and MFHPs - and point to significant improvements with anticipated technological gains.

  10. High-power pulse trains excited by modulated continuous waves

    E-Print Network [OSTI]

    Wang, Yan; Li, Lu; Malomed, Boris A

    2015-01-01

    Pulse trains growing from modulated continuous waves (CWs) are considered, using solutions of the Hirota equation for solitons on a finite background. The results demonstrate that pulses extracted from the maximally compressed trains can propagate preserving their shape and forming robust arrays. The dynamics of double high-power pulse trains produced by modulated CWs in a model of optical fibers, including the Raman effect and other higher-order terms, is considered in detail too. It is demonstrated that the double trains propagate in a robust form, with frequencies shifted by the Raman effect.

  11. Testing Density Wave Theory with Resolved Stellar Populations around Spiral Arms in M81

    E-Print Network [OSTI]

    Choi, Yumi; Williams, Benjamin F; Weisz, Daniel R; Skillman, Evan D; Fouesneau, Morgan; Dolphin, Andrew E

    2015-01-01

    Stationary density waves rotating at a constant pattern speed $\\Omega_{\\rm P}$ would produce age gradients across spiral arms. We test whether such age gradients are present in M81 by deriving the recent star formation histories (SFHs) of 20 regions around one of M81's grand-design spiral arms. For each region, we use resolved stellar populations to determine the SFH by modeling the observed color-magnitude diagram (CMD) constructed from archival Hubble Space Telescope (HST) F435W and F606W imaging. Although we should be able to detect systematic time delays in our spatially-resolved SFHs, we find no evidence of star formation propagation across the spiral arm. Our data therefore provide no convincing evidence for a stationary density wave with a single pattern speed in M81, and instead favor the scenario of kinematic spiral patterns that are likely driven by tidal interactions with the companion galaxies M82 and NGC 3077.

  12. DENSITY WAVES EXCITED BY LOW-MASS PLANETS IN PROTOPLANETARY DISKS. I. LINEAR REGIME

    SciTech Connect (OSTI)

    Dong, Ruobing; Stone, James M.; Petrovich, Cristobal; Rafikov, Roman R. E-mail: rrr@astro.princeton.edu E-mail: cpetrovi@astro.princeton.edu

    2011-11-01

    Density waves excited by planets embedded in protoplanetary disks play a central role in planetary migration and gap opening processes. We carry out two-dimensional shearing sheet simulations to study the linear regime of wave evolution with the grid-based code Athena and provide detailed comparisons with theoretical predictions. Low-mass planets (down to {approx}0.03 M{sub Circled-Plus} at 1 AU) and high spatial resolution (256 grid points per scale height) are chosen to mitigate the effects of wave nonlinearity. To complement the existing numerical studies, we focus on the primary physical variables such as the spatial profile of the wave, torque density, and the angular momentum flux carried by the wave, instead of secondary quantities such as the planetary migration rate. Our results show percent level agreement with theory in both physical and Fourier spaces. New phenomena such as the change of the toque density sign far from the planet are discovered and discussed. Also, we explore the effect of the numerical algorithms and find that a high order of accuracy, high resolution, and an accurate planetary potential are crucial to achieve good agreement with the theory. We find that the use of a too large time step without properly resolving the dynamical timescale around the planet produces incorrect results and may lead to spurious gap opening. Global simulations of planet migration and gap opening violating this requirement may be affected by spurious effects resulting in, e.g., the incorrect planetary migration rate and gap opening mass.

  13. Speech articulator measurements using low power EM-wave sensors

    SciTech Connect (OSTI)

    Holzrichter, J.F.; Burnett, G.C.; Ng, L.C.; Lea, W.A.

    1998-01-01

    Very low power electromagnetic (EM) wave sensors are being used to measure speech articulator motions as speech is produced. Glottal tissue oscillations, jaw, tongue, soft palate, and other organs have been measured. Previously, microwave imaging (e.g., using radar sensors) appears not to have been considered for such monitoring. Glottal tissue movements detected by radar sensors correlate well with those obtained by established laboratory techniques, and have been used to estimate a voiced excitation function for speech processing applications. The noninvasive access, coupled with the small size, low power, and high resolution of these new sensors, permit promising research and development applications in speech production, communication disorders, speech recognition and related topics. {copyright} {ital 1998 Acoustical Society of America.}

  14. Field induced spin density wave and spiral phases in a layered antiferromagnet

    SciTech Connect (OSTI)

    Stone, Matthew B.; Lumsden, Mark D.; Garlea, Vasile O.; Grenier, B.; Ressouche, E.; Samulon, Eric C.; Fisher, Ian R.

    2015-07-28

    We determine the low-field ordered magnetic phases of the S=1 dimerized antiferromagnet Ba3Mn2O8 using single crystal neutron diffraction. We find that for magnetic fields between ?0H=8.80 T and 10.56 T applied along the [1\\bar{1}0] direction the system exhibits spin density wave order with incommensurate wave vectors of type (?,?,?). For ?0H > 10.56 T, the magnetic order changes to a spiral phase with incommensurate wave vectors only along the [hh0] direction. For both field induced ordered phases, the magnetic moments are lying in the plane perpendicular to the field direction. The nature of these two transitions is fundamentally different: the low-field transition is a second order transition to a spin-density wave ground state, while the one at higher field, toward the spiral phase, is of first order.

  15. Wave propagation and power deposition in magnetically enhanced inductively coupled and helicon plasma sources

    E-Print Network [OSTI]

    Kushner, Mark

    Wave propagation and power deposition in magnetically enhanced inductively coupled and helicon are increased, axial standing wave patterns occur with substantial power deposition downstream. The ability processing are of interest because of their ability to deposit power within the volume of the plasma beyond

  16. Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid

    E-Print Network [OSTI]

    Victoria, University of

    Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot Boronowski Committee Integration of Wave and Tidal Power into the Haida Gwaii Electrical Grid by Susan Margot only be practical at power penetration levels less than 20%. #12;iv Table of Contents Supervisory

  17. Revisiting the emission from relativistic blast waves in a density-jump medium

    SciTech Connect (OSTI)

    Geng, J. J.; Huang, Y. F.; Dai, Z. G. [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Wu, X. F. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China); Li, Liang, E-mail: hyf@nju.edu.cn, E-mail: dzg@nju.edu.cn, E-mail: xfwu@pmo.ac.cn [Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm (Sweden)

    2014-09-01

    Re-brightening bumps are frequently observed in gamma-ray burst afterglows. Many scenarios have been proposed to interpret the origin of these bumps, of which a blast wave encountering a density-jump in the circumburst environment has been questioned by recent works. We develop a set of differential equations to calculate the relativistic outflow encountering the density-jump by extending the work of Huang et al. This approach is a semi-analytic method and is very convenient. Our results show that late high-amplitude bumps cannot be produced under common conditions, rather only a short plateau may emerge even when the encounter occurs at an early time (<10{sup 4} s). In general, our results disfavor the density-jump origin for those observed bumps, which is consistent with the conclusion drawn from full hydrodynamics studies. The bumps thus should be caused by other scenarios.

  18. High-density thermoelectric power generation and nanoscale thermal metrology

    E-Print Network [OSTI]

    Mayer, Peter (Peter Matthew), 1978-

    2007-01-01

    Thermoelectric power generation has been around for over 50 years but has seen very little large scale implementation due to the inherently low efficiencies and powers available from known materials. Recent material advances ...

  19. Power-Law Wave Functions and Generalized Parton Distributions for Pion

    E-Print Network [OSTI]

    A. Mukherjee; I. V. Musatov; H. C. Pauli; A. V. Radyushkin

    2003-02-03

    We propose a model for generalized parton distributions of the pion based on the power-law ansatz for the effective light-cone wave function.

  20. MHK Projects/Wave Powered Pumping of Seawater for On Shore Use...

    Open Energy Info (EERE)

    MHK ProjectsWave Powered Pumping of Seawater for On Shore Use and Electrical Generation < MHK Projects Jump to: navigation, search << Return to the MHK database homepage Loading...

  1. IEEE MICROWAVE AND GUIDED WAVE LETTERS, VOL. 8, NO. 3, MARCH 1998 133 A High-Efficiency Traveling-Wave Power

    E-Print Network [OSTI]

    York, Robert A.

    to that of an optimum load for each device, thus realizing a traveling-wave power amplifier. The results for a 1­9-GHz. Additionally, power is lost to backward wave excitation on the artificial output line. A goal of this research port, thus real- izing a traveling wave power amplifier (TWPA). A 1­9-GHz coplanar waveguide (CPW

  2. Toward PDN Resource Estimation: A Law of General Power Density

    E-Print Network [OSTI]

    Kahng, Andrew B.

    -characterized power models. At all design levels, the most important input is the switching ac- tivity information to system-level interconnect predic- tion for modern ICs. PDN design and verification require accurate power placement or switch- ing information is rarely available, so that designers either rely on pessimistic

  3. High Energy Density Utracapacitors: Low-Cost, High Energy and Power Density, Nanotube-Enhanced Ultracapacitors

    SciTech Connect (OSTI)

    2010-04-01

    Broad Funding Opportunity Announcement Project: FastCAP is improving the performance of an ultracapacitor—a battery-like electronic device that can complement, and possibly even replace, an HEV or EV battery pack. Ultracapacitors have many advantages over conventional batteries, including long lifespans (over 1 million cycles, as compared to 10,000 for conventional batteries) and better durability. Ultracapacitors also charge more quickly than conventional batteries, and they release energy more quickly. However, ultracapacitors have fallen short of batteries in one key metric: energy density—high energy density means more energy storage. FastCAP is redesigning the ultracapacitor’s internal structure to increase its energy density. Ultracapacitors traditionally use electrodes made of irregularly shaped, porous carbon. FastCAP’s ultracapacitors are made of tiny, aligned carbon nanotubes. The nanotubes provide a regular path for ions moving in and out of the ultracapacitor’s electrode, increasing the overall efficiency and energy density of the device.

  4. Effect of a nonlinear power take off on a wave energy converter 

    E-Print Network [OSTI]

    Bailey, Helen Louise

    2011-11-22

    This thesis is titled The influence of a nonlinear Power Take Off on a Wave Energy Converter. It looks at the effect that having a nonlinear Power Take Off (PTO) has on an inertial referenced, slack moored, point absorber, ...

  5. Optical properties of the Ce and La ditelluride charge density wave compounds

    SciTech Connect (OSTI)

    Lavagnini, M.; Sacchetti, A.; Degiorgi, L.; /Zurich, ETH; Shin, K.Y.; Fisher, I.R.; /Stanford U., Geballe Lab. /Stanford U., Appl. Phys. Dept.

    2010-02-15

    The La and Ce di-tellurides LaTe{sub 2} and CeTe{sub 2} are deep in the charge-density-wave (CDW) ground state even at 300 K. We have collected their electrodynamic response over a broad spectral range from the far infrared up to the ultraviolet. We establish the energy scale of the single particle excitation across the CDW gap. Moreover, we find that the CDW collective state gaps a very large portion of the Fermi surface. Similarly to the related rare earth tri-tellurides, we envisage that interactions and Umklapp processes play a role in the onset of the CDW broken symmetry ground state.

  6. Physical interpretation of fractional diffusion-wave equation via lossy media obeying frequency power law

    E-Print Network [OSTI]

    Physical interpretation of fractional diffusion-wave equation via lossy media obeying frequency power law W. Chen and S. Holm Simula Research Laboratory, P. O. Box. 134, 1325 Lysaker, Norway (15 March 2003) The fractional diffusion-wave equation (FDWE)1,2 is a recent generalization of diffusion and wave

  7. High power continuous-wave titanium:sapphire laser

    DOE Patents [OSTI]

    Erbert, G.V.; Bass, I.L.; Hackel, R.P.; Jenkins, S.L.; Kanz, V.K.; Paisner, J.A.

    1993-09-21

    A high-power continuous-wave laser resonator is provided, wherein first, second, third, fourth, fifth and sixth mirrors form a double-Z optical cavity. A first Ti:sapphire rod is disposed between the second and third mirrors and at the mid-point of the length of the optical cavity, and a second Ti:sapphire rod is disposed between the fourth and fifth mirrors at a quarter-length point in the optical cavity. Each Ti:sapphire rod is pumped by two counter-propagating pump beams from a pair of argon-ion lasers. For narrow band operation, a 3-plate birefringent filter and an etalon are disposed in the optical cavity so that the spectral output of the laser consists of 5 adjacent cavity modes. For increased power, seventy and eighth mirrors are disposed between the first and second mirrors to form a triple-Z optical cavity. A third Ti:sapphire rod is disposed between the seventh and eighth mirrors at the other quarter-length point in the optical cavity, and is pumped by two counter-propagating pump beams from a third pair of argon-ion lasers. 5 figures.

  8. High power continuous-wave titanium:sapphire laser

    DOE Patents [OSTI]

    Erbert, Gaylen V. (Livermore, CA); Bass, Isaac L. (Castro Valley, CA); Hackel, Richard P. (Livermore, CA); Jenkins, Sherman L. (Livermore, CA); Kanz, Vernon K. (Livermore, CA); Paisner, Jeffrey A. (Danville, CA)

    1993-01-01

    A high-power continuous-wave laser resonator (10) is provided, wherein first, second, third, fourth, fifth and sixth mirrors (11-16) form a double-Z optical cavity. A first Ti:Sapphire rod (17) is disposed between the second and third mirrors (12,13) and at the mid-point of the length of the optical cavity, and a second Ti:Sapphire rod (18) is disposed between the fourth and fifth mirrors (14,15) at a quarter-length point in the optical cavity. Each Ti:Sapphire rod (17,18) is pumped by two counter-propagating pump beams from a pair of argon-ion lasers (21-22, 23-24). For narrow band operation, a 3-plate birefringent filter (36) and an etalon (37) are disposed in the optical cavity so that the spectral output of the laser consists of 5 adjacent cavity modes. For increased power, seventy and eighth mirrors (101, 192) are disposed between the first and second mirrors (11, 12) to form a triple-Z optical cavity. A third Ti:Sapphire rod (103) is disposed between the seventh and eighth mirrors (101, 102) at the other quarter-length point in the optical cavity, and is pumped by two counter-propagating pump beams from a third pair of argon-ion lasers (104, 105).

  9. A Framework to Determine the Probability Density Function for the Output Power of Wind Farms

    E-Print Network [OSTI]

    Dominguez-Garcia, Alejandro

    A Framework to Determine the Probability Density Function for the Output Power of Wind Farms Sairaj to the power output of a wind farm while factoring in the availability of the wind turbines in the farm availability model for the wind turbines, we propose a method to determine the wind-farm power output pdf

  10. Low Power Multilevel Interconnect Networks Using Wave-Pipelined Multiplexed (WPM) Routing

    E-Print Network [OSTI]

    Joshi, Ajay

    Low Power Multilevel Interconnect Networks Using Wave-Pipelined Multiplexed (WPM) Routing Ajay 30332, USA {joshi, vinita, jeff}@ece.gatech.edu Abstract A low power multilevel interconnect architecture that uses wave-pipelined multiplexed (WPM) interconnect routing is proposed in this paper. WPM

  11. Hyperscaling at the spin density wave quantum critical point in two dimensional metals

    E-Print Network [OSTI]

    Patel, Aavishkar A; Sachdev, Subir

    2015-01-01

    The hyperscaling property implies that spatially isotropic critical quantum states in $d$ spatial dimensions have a specific heat which scales with temperature as $T^{d/z}$, and an optical conductivity which scales with frequency as $\\omega^{(d-2)/z}$ for $\\omega \\gg T$, where $z$ is the dynamic critical exponent. We examine the spin-density-wave critical fixed point of metals in $d=2$ found by Sur and Lee (Phys. Rev. B 91, 125136 (2015)) in an expansion in $\\epsilon = 3-d$. We find that the contributions of the "hot spots" on the Fermi surface to the optical conductivity and specific heat obey hyperscaling (up to logarithms), and agree with the results of the large $N$ analysis of the optical conductivity by Hartnoll et al. (Phys. Rev. B 84, 125115 (2011)). With a small bare velocity of the boson associated with the spin density wave order, there is an intermediate energy regime where hyperscaling is violated with $d \\rightarrow d_t$, where $d_t = 1$ is the number of dimensions transverse to the Fermi surfac...

  12. A comparison of parametric decay of oblique Langmuir wave in high and low density magneto-plasmas

    SciTech Connect (OSTI)

    Shahid, M.; Hussain, A.; Department of Physics, Government College University, Lahore-54000 ; Murtaza, G.

    2013-09-15

    The parametric decay instability of an obliquely propagating Langmuir wave into the low-frequency electromagnetic shear Alfven wave and the Left-Handed Circularly Polarized wave has been investigated in an electron-ion plasma, immersed in a uniform external magnetic field. Quantum magneto-hydrodynamic model has been used to find the linear and non-linear response of a high density quantum magneto-plasma. Going to the classical limit (??0) retrieves the results for low density classical plasma. Nonlinear dispersion relations and growth rates are derived with analytically and numerically. It is observed that growth rate in the high density degenerate magneto-plasma increases exponentially, while in the low density classical case it increases logarithmically.

  13. Stable formation of ultrahigh power-density 248 nm channels in Xe cluster targets

    SciTech Connect (OSTI)

    Borisov, Alex B.; Racz, Ervin; Khan, Shahab F.; Poopalasingam, Sankar; McCorkindale, John C.; Boguta, John; Longworth, James W.; Rhodes, Charles K.

    2012-07-11

    The optimization of relativistic and ponderomotive self-channeling of ultra-powerful 248 nm laser pulses launched in underdense plasmas with an appropriate longitudinal gradient in the electron density profile located at the initial stage of the self-channeling leads to (1) stable channel formation and (2) highly efficient power compression producing power densities in the 10{sup 19}-10{sup 20} W/cm{sup 3} range. The comparison of theoretical studies with experimental results involving the correlation of (a) Thomson images of the electron density with (b) x-ray images of the channel morphology demonstrates that more than 90% of the incident 248 nm power can be trapped in stable channels and that this stable propagation can be extended to power levels significantly exceeding the critical power of the self-channeling process.

  14. Thin liquid lithium targets for high power density

    E-Print Network [OSTI]

    McDonald, Kirk

    High charge state High velocity flow ~60 m/s High heat capacity of Li Absorbs power deposited pressure > 6 MPa (for > ~150 m/s Li jet) #12;10 PV601 PV 602 HV 603 Vacuum Chamber Pressure Vessel 1 in. tubing 1/2 in. tubing Deflector Nozzle Viewport ToVacuum Pump To High Pressure Gas Supply Viewport

  15. Electromagnetic Potentials Basis for Energy Density and Power Flux

    E-Print Network [OSTI]

    H. E. Puthoff

    2010-09-26

    It is well understood that various alternatives are available within EM theory for the definitions of energy density, momentum transfer, EM stress-energy tensor, and so forth. Although the various options are all compatible with the basic equations of electrodynamics (e.g., Maxwell's equations, Lorentz force law, gauge invariance), nonetheless certain alternative formulations lend themselves to being seen as preferable to others with regard to the transparency of their application to physical problems of interest. Here we argue for the transparency of an option based on use of the EM potentials alone.

  16. Dynamics and afterglow light curves of gamma-ray burst blast waves encountering a density bump or void

    SciTech Connect (OSTI)

    Uhm, Z. Lucas; Zhang, Bing, E-mail: uhm@pku.edu.cn, E-mail: zhang@physics.unlv.edu [Kavli Institute for Astronomy and Astrophysics, Peking University, Beijing 100871 (China)

    2014-07-01

    We investigate the dynamics and afterglow light curves of gamma-ray burst blast waves that encounter various density structures (such as bumps, voids, or steps) in the surrounding ambient medium. We present and explain the characteristic response features that each type of density structure in the medium leaves on the forward shock (FS) and reverse shock (RS) dynamics for blast waves with either a long-lived or short-lived RS. We show that when the ambient medium density drops, the blast waves exhibit in some cases a period of an actual acceleration (even during their deceleration stage) due to adiabatic cooling of blast waves. Comparing numerical examples that have different shapes of bumps or voids, we propose a number of consistency tests that must be satisfied by correct modeling of blast waves. Our model results successfully pass these tests. Employing a Lagrangian description of blast waves, we perform a sophisticated calculation of afterglow emission. We show that as a response to density structures in the ambient medium, the RS light curves produce more significant variations than the FS light curves. Some observed features (such as rebrightenings, dips, or slow wiggles) can be more easily explained within the RS model. We also discuss the origin of these different features imprinted on the FS and RS light curves.

  17. Evaluation of high power density annular fuel application in the Korean OPR-1000 reactor

    E-Print Network [OSTI]

    Zhang, Liang, Ph. D.. Massachusetts Institute of Technology

    2009-01-01

    Compared to the traditional solid fuel geometry for PWRs, the internally and externally cooled annular fuel offers the potential to increase the core power density while maintaining or increasing safety margins. It is ...

  18. Afghanistan Wind Power Density at 50-m Above Ground Level GIS...

    Open Energy Info (EERE)

    Wind Power Density at 50-m Above Ground Level GIS Data This dataset was developed by the National Renewable Energy Laboratory (NREL) for the U.S. Agency for International...

  19. NEUTRONIC AND THERMAL HYDRAULIC DESIGNS OF ANNULAR FUEL FOR HIGH POWER DENSITY BWRS

    E-Print Network [OSTI]

    Morra, P.

    As a promising new fuel for high power density light water reactors, the feasibility of using annular fuel for BWR services is explored from both thermal hydraulic and neutronic points of view. Keeping the bundle size ...

  20. Development of optimized core design and analysis methods for high power density BWRs

    E-Print Network [OSTI]

    Shirvan, Koroush

    2013-01-01

    Increasing the economic competitiveness of nuclear energy is vital to its future. Improving the economics of BWRs is the main goal of this work, focusing on designing cores with higher power density, to reduce the BWR ...

  1. Assessment of helical-cruciform fuel rods for high power density LWRs

    E-Print Network [OSTI]

    Conboy, Thomas M

    2010-01-01

    In order to significantly increase the power density of Light Water Reactors (LWRs), the helical-cruciform (HC) fuel rod assembly has been proposed as an alternative to traditional fuel geometry. The HC assembly is a ...

  2. Photoemission study of the electronic structure and charge density waves of Na?Ti?Sb?O

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

    Tan, S. Y. [Science and Technology on Surface Physics and Chemistry Lab., Mianyang (China); Fundan Univ., Shanghai (China); Jiang, J. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Ye, Z. R. [Fundan Univ., Shanghai (China); Niu, X. H. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Song, Y. [Rice Univ., Houston, TX (United States); Zhang, C. L. [Rice Univ., Houston, TX (United States); Univ. of Tennessee, Knoxville, TN (United States); Dai, P. C. [Rice Univ., Houston, TX (United States); Xie, B. P. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China); Lai, X. C. [Science and Technology on Surface Physics and Chemistry Lab., Mianyang (China); Feng, D. L. [Fundan Univ., Shanghai (China); Nanjing Univ., Nanjing (China)

    2015-04-30

    The electronic structure of Na?Ti?Sb?O single crystal is studied by photon energy and polarization dependent angle-resolved photoemission spectroscopy (ARPES). The obtained band structure and Fermi surface agree well with the band structure calculation of Na?Ti?Sb?O in the non-magnetic state, which indicates that there is no magnetic order in Na?Ti?Sb?O and the electronic correlation is weak. Polarization dependent ARPES results suggest the multi-band and multi-orbital nature of Na?Ti?Sb?O. Photon energy dependent ARPES results suggest that the electronic structure of Na?Ti?Sb?O is rather two-dimensional. Moreover, we find a density wave energy gap forms below the transition temperature and reaches 65 meV at 7 K, indicating that Na?Ti?Sb?O is likely a weakly correlated CDW material in the strong electron-phonon interaction regime. (author)

  3. Photoemission study of the electronic structure and charge density waves of Na?Ti?Sb?O

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

    Tan, S. Y.; Jiang, J.; Ye, Z. R.; Niu, X. H.; Song, Y.; Zhang, C. L.; Dai, P. C.; Xie, B. P.; Lai, X. C.; Feng, D. L.

    2015-04-30

    The electronic structure of Na?Ti?Sb?O single crystal is studied by photon energy and polarization dependent angle-resolved photoemission spectroscopy (ARPES). The obtained band structure and Fermi surface agree well with the band structure calculation of Na?Ti?Sb?O in the non-magnetic state, which indicates that there is no magnetic order in Na?Ti?Sb?O and the electronic correlation is weak. Polarization dependent ARPES results suggest the multi-band and multi-orbital nature of Na?Ti?Sb?O. Photon energy dependent ARPES results suggest that the electronic structure of Na?Ti?Sb?O is rather two-dimensional. Moreover, we find a density wave energy gap forms below the transition temperature and reaches 65 meV atmore »7 K, indicating that Na?Ti?Sb?O is likely a weakly correlated CDW material in the strong electron-phonon interaction regime. (author)« less

  4. Scattering of electromagnetic waves by vortex density structures associated with interchange instability: Analytical and large scale plasma simulation results

    SciTech Connect (OSTI)

    Sotnikov, V.; Kim, T.; Lundberg, J.; Paraschiv, I.; Mehlhorn, T. A.

    2014-05-15

    The presence of plasma turbulence can strongly influence propagation properties of electromagnetic signals used for surveillance and communication. In particular, we are interested in the generation of low frequency plasma density irregularities in the form of coherent vortex structures. Interchange or flute type density irregularities in magnetized plasma are associated with Rayleigh-Taylor type instability. These types of density irregularities play an important role in refraction and scattering of high frequency electromagnetic signals propagating in the earth ionosphere, in high energy density physics, and in many other applications. We will discuss scattering of high frequency electromagnetic waves on low frequency density irregularities due to the presence of vortex density structures associated with interchange instability. We will also present particle-in-cell simulation results of electromagnetic scattering on vortex type density structures using the large scale plasma code LSP and compare them with analytical results.

  5. Dynamic power balance for nonlinear waves in unbalanced gain and loss landscapes

    E-Print Network [OSTI]

    Kominis, Yannis

    2015-01-01

    The presence of losses in nonlinear photonic structures is a crucial issue for modern applications. Active parts are introduced for wave power compensation resulting in unbalanced gain and loss landscapes where localized beam propagation is, in general, dynamically unstable. Here we provide generic sufficient conditions for the relation between the gain-loss and the refractive index profiles in order to ensure efficient wave trapping and stable propagation for a wide range of beam launching conditions such as initial power, angle of incidence and position. The stability is a consequence of an underlying dynamic power balance mechanism related to a conserved quantity of wave dynamics.

  6. LOW POWER SCANNER FOR HIGH-DENSITY ELECTRODE ARRAY NEURAL RECORDING

    E-Print Network [OSTI]

    Mahmoodi, Hamid

    of this research is to design a low power integrated system that can be used in vivo for scanning the electrode. A model created in Python provides input vectors and output comparison for the verification processLOW POWER SCANNER FOR HIGH-DENSITY ELECTRODE ARRAY NEURAL RECORDING A Thesis work submitted

  7. Smooth Light Curves from a Bumpy Ride: Relativistic Blast Wave Encounters a Density Jump

    SciTech Connect (OSTI)

    Nakar, Ehud; /Caltech; Granot, Jonathan; /KIPAC, Menlo Park

    2006-06-06

    Some gamma-ray burst (GRB) afterglow light curves show significant variability, which often includes episodes of rebrightening. Such temporal variability had been attributed in several cases to large fluctuations in the external density, or density ''bumps''. Here we carefully examine the effect of a sharp increase in the external density on the afterglow light curve by considering, for the first time, a full treatment of both the hydrodynamic evolution and the radiation in this scenario. To this end we develop a semi-analytic model for the light curve and carry out several elaborate numerical simulations using a one dimensional hydrodynamic code together with a synchrotron radiation code. Two spherically symmetric cases are explored in detail--a density jump in a uniform external medium, and a wind termination shock. The effect of density clumps is also constrained. Contrary to previous works, we find that even a very sharp (modeled as a step function) and large (by a factor of a >> 1) increase in the external density does not produce sharp features in the light curve, and cannot account for significant temporal variability in GRB afterglows. For a wind termination shock, the light curve smoothly transitions between the asymptotic power laws over about one decade in time, and there is no rebrightening in the optical or X-rays that could serve as a clear observational signature. For a sharp jump in a uniform density profile we find that the maximal deviation {Delta}{alpha}{sub max} of the temporal decay index {alpha} from its asymptotic value (at early and late times), is bounded (e.g, {Delta}{alpha}{sub max} < 0.4 for {alpha} = 10); {Delta}{alpha}{sub max} slowly increases with {alpha}, converging to {Delta}{alpha}{sub max} {approx} 1 at very large {alpha} values. Therefore, no optical rebrightening is expected in this case as well. In the X-rays, while the asymptotic flux is unaffected by the density jump, the fluctuations in {alpha} are found to be comparable to those in the optical. Finally, we discuss the implications of our results for the origin of the observed fluctuations in several GRB afterglows.

  8. Effect of electron-density gradients on propagation of radio waves in the mid-latitude trough. Master's thesis

    SciTech Connect (OSTI)

    Citrone, P.J.

    1991-01-01

    Partial contents of this thesis include: (1) Radio-wave propagation and the mid-latitude trough; (2) Ionospheric measurements; (3) Modification of time-dependent ionospheric model output with latitudinal electron-density profiles from digisonde trough depictions; (4) Ray-tracing simulations to examine ground range; and (5) Effects of three-dimensional gradients in electron density on radio-wave propagation in the trough region. Data is tabulated for geophysical conditions, solar activity level, geomagnetic activity level, conditions for vertical ray refraction to surface, and ray-tracing fixed-input conditions.

  9. Noise power spectral density of a fibre scattered-light interferometer with a semiconductor laser source

    SciTech Connect (OSTI)

    Alekseev, A E; Potapov, V T

    2013-10-31

    Spectral characteristics of the noise intensity fluctuations at the output of a scattered-light interferometer, caused by phase fluctuations of semiconductor laser radiation are considered. This kind of noise is one of the main factors limiting sensitivity of interferometric sensors. For the first time, to our knowledge, the expression is obtained for the average noise power spectral density at the interferometer output versus the degree of a light source coherence and length of the scattering segment. Also, the approximate expressions are considered which determine the power spectral density in the low-frequency range (up to 200 kHz) and in the limiting case of extended scattering segments. The expression obtained for the noise power spectral density agrees with experimental normalised power spectra with a high accuracy. (interferometry of radiation)

  10. E?H mode transition density and power in two types of inductively coupled plasma configuration

    SciTech Connect (OSTI)

    Wang, Jian; Du, Yin-chang; Zhang, Xiao; Zheng, Zhe; Liu, Yu; Xu, Liang; Wang, Pi; Cao, Jin-xiang, E-mail: jxcao@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-07-15

    E???H transition power and density were investigated at various argon pressures in inductively coupled plasma (ICP) in a cylindrical interlaid chamber. The transition power versus the pressure shows a minimum transition power at 4?Pa (?/?=1) for argon. Then the transition density hardly changes at low pressures (?/??1), but it increases clearly when argon pressure exceeds an appropriate value. In addition, both the transition power and transition density are lower in the re-entrant configuration of ICP compared with that in the cylindrical configuration of ICP. The result may be caused from the decrease of stochastic heating in the re-entrant configuration of ICP. This work is useful to understand E???H mode transition and control the transition points in real plasma processes.

  11. Method and apparatus for measuring the momentum, energy, power, and power density profile of intense particle beams

    DOE Patents [OSTI]

    Gammel, George M. (Merrick, NY); Kugel, Henry W. (Somerset, NJ)

    1992-10-06

    A method and apparatus for determining the power, momentum, energy, and power density profile of high momentum mass flow. Small probe projectiles of appropriate size, shape and composition are propelled through an intense particle beam at equal intervals along an axis perpendicular to the beam direction. Probe projectiles are deflected by collisions with beam particles. The net beam-induced deflection of each projectile is measured after it passes through the intense particle beam into an array of suitable detectors.

  12. Reduction operators and exact solutions of variable coefficient nonlinear wave equations with power nonlinearities

    E-Print Network [OSTI]

    Ding-jiang Huang; Qin-min Yang; Shui-geng Zhou

    2013-12-18

    Reduction operators, i.e. the operators of nonclassical (or conditional) symmetry of a class of variable coefficient nonlinear wave equations with power nonlinearities is investigated within the framework of singular reduction operator. A classification of regular reduction operators is performedwith respect to generalized extended equivalence groups. Exact solutions of some nonlinear wave model which are invariant under certain reduction operators are also constructed.

  13. Wave-plate structures, power selective optical filter devices, and optical systems using same

    DOE Patents [OSTI]

    Koplow, Jeffrey P. (San Ramon, CA)

    2012-07-03

    In an embodiment, an optical filter device includes an input polarizer for selectively transmitting an input signal. The device includes a wave-plate structure positioned to receive the input signal, which includes first and second substantially zero-order, zero-wave plates arranged in series with and oriented at an angle relative to each other. The first and second zero-wave plates are configured to alter a polarization state of the input signal passing in a manner that depends on the power of the input signal. Each zero-wave plate includes an entry and exit wave plate each having a fast axis, with the fast axes oriented substantially perpendicular to each other. Each entry wave plate is oriented relative to a transmission axis of the input polarizer at a respective angle. An output polarizer is positioned to receive a signal output from the wave-plate structure and selectively transmits the signal based on the polarization state.

  14. Making waves on CMB power spectrum and inflaton dynamics

    E-Print Network [OSTI]

    Masahiro Kawasaki; Fuminobu Takahashi; Tomo Takahashi

    2004-11-11

    We discuss cosmic microwave background anisotropies in models with an unconventional primordial power spectrum. In particular, we consider an initial power spectrum with some ``spiky'' corrections. Interestingly, such a primordial power spectrum generates ``wavy'' structure in the CMB angular power spectrum.

  15. Coordinated control and network integration of wave power farms 

    E-Print Network [OSTI]

    Nambiar, Anup Jayaprakash

    2012-11-29

    Significant progress has been made in the development of wave energy converters (WECs) during recent years, with prototypes and farms of WECs being installed in different parts of the world. With increasing sizes of ...

  16. Damping Pressure Pulsations in a Wave-Powered Desalination System

    E-Print Network [OSTI]

    Padhye, Nikhil

    Wave-driven reverse osmosis desalination systems can be a cost-effective option for providing a safe and reliable source of drinking water for large coastal communities. Such systems usually require the stabilization of ...

  17. Theoretical modelling of two wave-power devices

    E-Print Network [OSTI]

    Lovas, Stéphanie

    2010-01-01

    Many wave energy devices are currently studied. In this thesis we focus on two specific devices: the Oscillating Water Column (OWC), and the buoys. In the first part of this thesis we examine the effects of coastline ...

  18. Reply to comment by R. Bousquet et al. on ``Subduction factory: 1. Theoretical mineralogy, densities, seismic wave speeds

    E-Print Network [OSTI]

    Hacker, Bradley R.

    , densities, seismic wave speeds and H2O contents'' Bradley R. Hacker,1 Geoffrey A. Abers,2 Simon M. Peacock,3: Hacker, B. R., G. A. Abers, S. M. Peacock, and S. Johnson (2005), Reply to comment by R. Bousquet et al to calculate rock phys- ical properties at high to ultrahigh pressure. One approach [e.g., Hacker et al., 2003

  19. Vacuum behaviors around rarefaction waves to 1D compressible Navier-Stokes equations with density-dependent viscosity

    E-Print Network [OSTI]

    Quansen Jiu; Yi Wang; Zhouping Xin

    2011-09-05

    In this paper, we study the large time asymptotic behavior toward rarefaction waves for solutions to the 1-dimensional compressible Navier-Stokes equations with density-dependent viscosities for general initial data whose far fields are connected by a rarefaction wave to the corresponding Euler equations with one end state being vacuum. First, a global-in-time weak solution around the rarefaction wave is constructed by approximating the system and regularizing the initial data with general perturbations, and some a priori uniform-in-time estimates for the energy and entropy are obtained. Then it is shown that the density of any weak solution satisfying the natural energy and entropy estimates will converge to the rarefaction wave connected to vacuum with arbitrary strength in super-norm time-asymptotically. Our results imply, in particular, that the initial vacuum at far fields will remain for all the time which are in contrast to the case of non-vacuum rarefaction waves studied in \\cite{JWX} where all the possible vacuum states will vanish in finite time. Finally, it is proved that the weak solution becomes regular away from the vacuum region of the rarefaction wave.

  20. On the breaking of a plasma wave in a thermal plasma. I. The structure of the density singularity

    SciTech Connect (OSTI)

    Bulanov, Sergei V.; Esirkepov, Timur Zh.; Kando, Masaki; Koga, James K.; Pirozhkov, Alexander S.; Nakamura, Tatsufumi; Bulanov, Stepan S.; Schroeder, Carl B.; Esarey, Eric; Califano, Francesco; Pegoraro, Francesco

    2012-11-15

    The structure of the singularity that is formed in a relativistically large amplitude plasma wave close to the wave breaking limit is found by using a simple waterbag electron distribution function. The electron density distribution in the breaking wave has a typical 'peakon' form. The maximum value of the electric field in a thermal breaking plasma is obtained and compared to the cold plasma limit. The results of computer simulations for different initial electron distribution functions are in agreement with the theoretical conclusions. The after-wavebreak regime is then examined, and a semi-analytical model of the density evolution is constructed. Finally the results of two dimensional particle in cell simulations for different initial electron distribution functions are compared, and the role of thermal effects in enhancing particle injection is noted.

  1. Solitary and shock waves in discrete double power-law materials

    E-Print Network [OSTI]

    E. B. Herbold; V. F. Nesterenko

    2007-08-24

    A novel strongly nonlinear laminar metamaterial supporting new types of solitary and shock waves with impact energy mitigating capabilities is presented. It consists of steel plates with intermittent polymer toroidal rings acting as strongly nonlinear springs with large allowable strain. Their force-displacement relationship is described by the addition of two power-law relationships resulting in a solitary wave speed and width depending on the amplitude. This double nonlinearity allows splitting of an initial impulse into two separate strongly nonlinear solitary wave trains. Solitary and shock waves are observed experimentally and analyzed numerically in an assembly with Teflon o-rings.

  2. Method of Fabrication of High Power Density Solid Oxide Fuel Cells

    DOE Patents [OSTI]

    Pham, Ai Quoc (San Jose, CA); Glass, Robert S. (Livermore, CA)

    2008-09-09

    A method for producing ultra-high power density solid oxide fuel cells (SOFCs). The method involves the formation of a multilayer structure cells wherein a buffer layer of doped-ceria is deposited intermediate a zirconia electrolyte and a cobalt iron based electrode using a colloidal spray deposition (CSD) technique. For example, a cobalt iron based cathode composed of (La,Sr)(Co,Fe)O(LSCF) may be deposited on a zirconia electrolyte via a buffer layer of doped-ceria deposited by the CSD technique. The thus formed SOFC have a power density of 1400 mW/cm.sup.2 at 600.degree. C. and 900 mW/cm.sup.2 at 700.degree. C. which constitutes a 2-3 times increased in power density over conventionally produced SOFCs.

  3. Efficiency enhancement techniques for RF and millimeter wave power amplifiers

    E-Print Network [OSTI]

    Ogunnika, Olumuyiwa Temitope, 1978-

    2012-01-01

    Power amplifiers are the circuit blocks in wireless transceivers that require the largest power budget because of their relatively low efficiencies. RF designers cannot depend solely on the development better semiconductor ...

  4. Advanced, High Power, Next Scale, Wave Energy Conversion Device

    SciTech Connect (OSTI)

    Hart, Philip R.

    2011-09-27

    This presentation from the Water Peer Review highlights one of the program's marine and hyrokinetics device design projects to scale up the current Ocean Power Technology PowerBuoy from 150kW to 500kW.

  5. Effect of spatial density variation and O+ concentration on the growth and evolution of electromagnetic ion cyclotron waves

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

    Denton, R. E.; Jordanova, V. K.; Fraser, B. J.

    2014-10-01

    We simulate electromagnetic ion cyclotron (EMIC) wave growth and evolution within three regions, the plasmasphere (or plasmaspheric plume), the plasmapause, and the low-density plasmatrough outside the plasmapause. First, we use a ring current simulation with a plasmasphere model to model the particle populations that give rise to the instability for conditions observed on 9 June 2001. Then, using two different models for the cold ion composition, we do a full scale hybrid code simulation in dipole coordinates of the EMIC waves on a meridional plane at MLT = 18 and at 1900 UT within a range of L shell frommore »L = 4.9 to 6.7. EMIC waves were observed during June 9, 2001 by Geostationary Operational Environmental Satellite (GOES) spacecraft. While an exact comparison between observed and simulated spectra is not possible here, we do find significant similarities between the two, at least at one location within the region of largest wave growth. We find that the plasmapause is not a preferred region for EMIC wave growth, though waves can grow in that region. The density gradient within the plasmapause does, however, affect the orientation of wave fronts and wave vector both within the plasmapause and in adjacent regions. There is a preference for EMIC waves to be driven in the He+ band (frequencies between the O+ and He+ gyrofrequencies) within the plasmasphere, although they can also grow in the plasmatrough. If present, H+ band waves are more likely to grow in the plasmatrough. This fact, plus L dependence of the frequency and possible time evolution toward lower frequency waves, can be explained by a simple model. Large O+ concentration limits the frequency range of or even totally quenches EMIC waves. This is more likely to occur in the plasmatrough at solar maximum. Such large O+ concentration significantly affects the H+ cutoff frequency and hence the width in frequency of the stop band above the He+ gyrofrequency. EMIC wave surfaces predicted by cold plasma theory are altered by the finite temperature of the ring current H+.« less

  6. Effect of spatial density variation and O+ concentration on the growth and evolution of electromagnetic ion cyclotron waves

    SciTech Connect (OSTI)

    Denton, R. E.; Jordanova, V. K.; Fraser, B. J.

    2014-10-01

    We simulate electromagnetic ion cyclotron (EMIC) wave growth and evolution within three regions, the plasmasphere (or plasmaspheric plume), the plasmapause, and the low-density plasmatrough outside the plasmapause. First, we use a ring current simulation with a plasmasphere model to model the particle populations that give rise to the instability for conditions observed on 9 June 2001. Then, using two different models for the cold ion composition, we do a full scale hybrid code simulation in dipole coordinates of the EMIC waves on a meridional plane at MLT = 18 and at 1900 UT within a range of L shell from L = 4.9 to 6.7. EMIC waves were observed during June 9, 2001 by Geostationary Operational Environmental Satellite (GOES) spacecraft. While an exact comparison between observed and simulated spectra is not possible here, we do find significant similarities between the two, at least at one location within the region of largest wave growth. We find that the plasmapause is not a preferred region for EMIC wave growth, though waves can grow in that region. The density gradient within the plasmapause does, however, affect the orientation of wave fronts and wave vector both within the plasmapause and in adjacent regions. There is a preference for EMIC waves to be driven in the He+ band (frequencies between the O+ and He+ gyrofrequencies) within the plasmasphere, although they can also grow in the plasmatrough. If present, H+ band waves are more likely to grow in the plasmatrough. This fact, plus L dependence of the frequency and possible time evolution toward lower frequency waves, can be explained by a simple model. Large O+ concentration limits the frequency range of or even totally quenches EMIC waves. This is more likely to occur in the plasmatrough at solar maximum. Such large O+ concentration significantly affects the H+ cutoff frequency and hence the width in frequency of the stop band above the He+ gyrofrequency. EMIC wave surfaces predicted by cold plasma theory are altered by the finite temperature of the ring current H+.

  7. Universal power law for the energy spectrum of breaking Riemann waves

    E-Print Network [OSTI]

    Dmitry Pelinovsky; Efim Pelinovsky; Elena Kartashova; Tatjana Talipova; Ayrat Giniyatullin

    2013-06-30

    The universal power law for the spectrum of one-dimensional breaking Riemann waves is justified for the simple wave equation. The spectrum of spatial amplitudes at the breaking time $t = t_b$ has an asymptotic decay of $k^{-4/3}$, with corresponding energy spectrum decaying as $k^{-8/3}$. This spectrum is formed by the singularity of the form $(x-x_b)^{1/3}$ in the wave shape at the breaking time. This result remains valid for arbitrary nonlinear wave speed. In addition, we demonstrate numerically that the universal power law is observed for long time in the range of small wave numbers if small dissipation or dispersion is accounted in the viscous Burgers or Korteweg-de Vries equations.

  8. Power spectrum of electron number density perturbations at cosmological recombination epoch

    E-Print Network [OSTI]

    B. Venhlovska; B. Novosyadlyj

    2009-02-19

    The power spectrum of number density perturbations of free electrons is obtained for the epoch of cosmological recombination of hydrogen. It is shown that amplitude of the electron perturbations power spectrum of scales larger than acoustic horizon exceeds by factor of 17 the amplitude of baryon matter density ones (atoms and ions of hydrogen and helium). In the range of the first and second acoustic peaks such relation is 18, in the range of the third one 16. The dependence of such relations on cosmological parameters is analysed too.

  9. Time- and power-dependent operation of a parametric spin-wave amplifier

    SciTech Connect (OSTI)

    Brächer, T.; Heussner, F.; Pirro, P.; Fischer, T.; Geilen, M.; Heinz, B.; Lägel, B.; Serga, A. A.; Hillebrands, B.

    2014-12-08

    We present the experimental observation of the localized amplification of externally excited, propagating spin waves in a transversely in-plane magnetized Ni{sub 81}Fe{sub 19} magnonic waveguide by means of parallel pumping. By employing microfocussed Brillouin light scattering spectroscopy, we analyze the dependency of the amplification on the applied pumping power and on the delay between the input spin-wave packet and the pumping pulse. We show that there are two different operation regimes: At large pumping powers, the spin-wave packet needs to enter the amplifier before the pumping is switched on in order to be amplified while at low powers the spin-wave packet can arrive at any time during the pumping pulse.

  10. Whistler wave radiation from a pulsed loop antenna located in a cylindrical duct with enhanced plasma density

    SciTech Connect (OSTI)

    Kudrin, Alexander V.; Shkokova, Natalya M.; Ferencz, Orsolya E.; Zaboronkova, Tatyana M.

    2014-11-15

    Pulsed radiation from a loop antenna located in a cylindrical duct with enhanced plasma density is studied. The radiated energy and its distribution over the spatial and frequency spectra of the excited waves are derived and analyzed as functions of the antenna and duct parameters. Numerical results referring to the case where the frequency spectrum of the antenna current is concentrated in the whistler range are reported. It is shown that under ionospheric conditions, the presence of an artificial duct with enhanced density can lead to a significant increase in the energy radiated from a pulsed loop antenna compared with the case where the same source is immersed in the surrounding uniform magnetoplasma. The results obtained can be useful in planning active ionospheric experiments with pulsed electromagnetic sources operated in the presence of artificial field-aligned plasma density irregularities that are capable of guiding whistler waves.

  11. MHK Technologies/Gyroscopic wave power generation system | Open Energy

    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050Enermar < MHK TechnologiesCat WaveGyroWaveGen

  12. Power Electronic Topologies with High Density Power Conversion and Galvanic Isolation for Utility Interface 

    E-Print Network [OSTI]

    Krishnamoorthy, Harish Sarma

    2015-01-26

    the transformers, inductors and DC electrolytic capacitors. Instead of using a line frequency transformer to interface any power electronic system with the utility grid directly, it is possible to use a power converter to transform the line frequency AC into a...

  13. Estimation of Heavy Ion Densities From Linearly Polarized EMIC Waves At Earth

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Lee, Dong-Hun

    2014-02-24

    Linearly polarized EMIC waves are expected to concentrate at the location where their wave frequency satisfies the ion-ion hybrid (IIH) resonance condition as the result of a mode conversion process. In this letter, we evaluate absorption coefficients at the IIH resonance in the Earth geosynchronous orbit for variable concentrations of helium and azimuthal and field-aligned wave numbers in dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentration, it only occurs for a limited range of azimuthal and field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Our results suggest that, at L = 6.6, linearly polarized EMIC waves can be generated via mode conversion from the compressional waves near the crossover frequency. Consequently, the heavy ion concentration ratio can be estimated from observations of externally generated EMIC waves that have polarization.

  14. Continuous-wave high-power rotational Raman generation in molecular deuterium

    E-Print Network [OSTI]

    Yavuz, Deniz

    Continuous-wave high-power rotational Raman generation in molecular deuterium J. T. Green, D. E the generation of more than 300 mW of rotational Stokes output power in a CW Raman laser. The generation and the generated wavelengths. Advances in high-reflectivity, ultralow loss dielectric coatings have allowed CW

  15. Increasing hurricane wave power along the U.S. Atlantic and Gulf coasts

    E-Print Network [OSTI]

    Bromirski, Peter D.

    erosion along the North Carolina coast [Dolan and Davis, 1992]. From a coastal management and planningIncreasing hurricane wave power along the U.S. Atlantic and Gulf coasts Peter D. Bromirski1 power index (WPI) increases significantly in the Atlantic during the mid-1990s, resulting largely from

  16. High Performance Circuits for Power Management and Millimeter Wave Applications 

    E-Print Network [OSTI]

    Amer, Ahmed 1979-

    2012-01-23

    to achieve the required goals in terms of small silicon area and power consumption while at the same time achieve high performance. Four key building blocks in power management and a switchable harmonic mixer with pre-amplifier and poly-phase generator as a...

  17. Non-contact Low Power EEG/ECG Electrode for High Density Wearable Biopotential Sensor

    E-Print Network [OSTI]

    Cauwenberghs, Gert

    Non-contact Low Power EEG/ECG Electrode for High Density Wearable Biopotential Sensor Networks Yu Mchi@ucsd.edu Abstract--A non-contact capacitive biopotential electrode with a common-mode noise senses the local biopotential with a differential gain of 46dB over a 1-100Hz bandwidth. Signals

  18. 2012 Jonathan G. Lange IMPROVING LITHIUM-ION BATTERY POWER AND ENERGY DENSITIES USING

    E-Print Network [OSTI]

    Braun, Paul

    1 ©2012 Jonathan G. Lange #12;1 IMPROVING LITHIUM-ION BATTERY POWER AND ENERGY DENSITIES USING ABSTRACT Lithium-ion batteries are commonly used as energy storage devices in a variety of applications. The cathode architectures and materials have a large influence on the performance of lithium-ion batteries

  19. Copper nanocrystal modified activated carbon for supercapacitors with enhanced volumetric energy and power density

    E-Print Network [OSTI]

    Cao, Guozhong

    Copper nanocrystal modified activated carbon for supercapacitors with enhanced volumetric energy of Cu can greatly increase the volumetric capacitance and power density of AC. online 4 March 2013 Keywords: Supercapacitor Copper Volumetric capacitance Activated carbon a b s t r a c

  20. Influence of defects on the charge density wave of ([SnSe]1+?)1(VSe2)1 ferecrystals

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

    Falmbigl, Matthias; Putzky, Daniel; Ditto, Jeffrey; Esters, Marco; Bauers, Sage R.; Ronning, Filip; Johnson, David C.

    2015-07-14

    A series of ferecrystalline compounds ([SnSe]1+?)1(VSe2)1 with varying Sn/V ratios were synthesized using the modulated elemental reactant technique. Temperature-dependent specific heat data reveal a phase transition at 102 K, where the heat capacity changes abruptly. An abrupt increase in electrical resistivity occurs at the same temperature, correlated with an abrupt increase in the Hall coefficient. Combined with the magnitude and nature of the specific heat discontinuity, this suggests that the transition is similar to the charge density wave transitions in transition metal dichalcogenides. An ordered intergrowth was formed over a surprisingly wide compositional range of Sn/V ratios of 0.89 ?more »1 + ? ? 1.37. X-ray diffraction and transmission electron microscopy reveal the formation of various volume defects in the compounds in response to the nonstoichiometry. The electrical resistivity and Hall coefficient data of samples with different Sn/V ratios show systematic variation in the carrier concentration with the Sn/V ratio. There is no significant change in the onset temperature of the charge density wave transition, only a variation in the carrier densities before and after the transition. Given the sensitivity of the charge density wave transitions of transition metal dichalcogenides to variations in composition, it is very surprising that the charge density wave transition observed at 102 K for ([SnSe]1.15)1(VSe2)1 is barely influenced by the nonstoichiometry and structural defects. As a result, this might be a consequence of the two-dimensional nature of the structurally independent VSe2 layers.« less

  1. Tapping into Wave and Tidal Ocean Power: 15% Water Power by 2030...

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

    Office What are the key documents? Mapping and Assessment of the United States Ocean Wave Energy Resource pdf here Assessment of Energy Production Potential from Tidal Streams...

  2. MHK Technologies/SyncWave Power Resonator | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050Enermar <OMIS D ESurgeWEC < MHK< MHKSyncWave

  3. Quasiparticle interference, quasiparticle interactions, and the origin of the charge density wave in 2H-NbSe?

    SciTech Connect (OSTI)

    Arguello, C. J. [Columbia Univ., New York, NY (United States); Valla, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rosenthal, E. P. [Columbia Univ., New York, NY (United States); Andrade, E. F. [Columbia Univ., New York, NY (United States); Jin, W. [Columbia Univ., New York, NY (United States); Yeh, P. C. [Columbia Univ., New York, NY (United States); Zaki, N. [Columbia Univ., New York, NY (United States); Jia, S. [Princeton Univ., NJ (United States); Cava, R. J. [Princeton Univ., NJ (United States); Fernandes, R. M. [Univ., of Minnesota, Minneapolis, MN (United States); Millis, A. J. [Columbia Univ., New York, NY (United States); Osgood, Jr., R. M. [Columbia Univ., New York, NY (United States); Princeton Univ., Princeton, NJ (United States); Pasupathy, A. N. [Columbia Univ., New York, NY (United States)

    2015-01-01

    We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe?, that we measure by scanning tunneling spectroscopic imaging. We show from the momentum and energy dependence of the quasiparticle interference that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe?. We demonstrate that by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wavevector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiology and the interactions. In 2H-NbSe?, we use this combination to show that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the CDW ordering wave vector.

  4. Quasiparticle interference, quasiparticle interactions, and the origin of the charge density wave in 2H-NbSe?

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

    Arguello, C. J.; Valla, T.; Rosenthal, E. P.; Andrade, E. F.; Jin, W.; Yeh, P. C.; Zaki, N.; Jia, S.; Cava, R. J.; Fernandes, R. M.; et al

    2015-01-20

    We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe?, that we measure by scanning tunneling spectroscopic imaging. We show from the momentum and energy dependence of the quasiparticle interference that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe?. We demonstrate that by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wavevector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiology andmore »the interactions. In 2H-NbSe?, we use this combination to show that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the CDW ordering wave vector.« less

  5. Quasiparticle interference, quasiparticle interactions, and the origin of the charge density wave in 2H-NbSe?

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

    Arguello, C. J. [Columbia Univ., New York, NY (United States); Valla, T. [Brookhaven National Lab. (BNL), Upton, NY (United States); Rosenthal, E. P. [Columbia Univ., New York, NY (United States); Andrade, E. F. [Columbia Univ., New York, NY (United States); Jin, W. [Columbia Univ., New York, NY (United States); Yeh, P. C. [Columbia Univ., New York, NY (United States); Zaki, N. [Columbia Univ., New York, NY (United States); Jia, S. [Princeton Univ., NJ (United States); Cava, R. J. [Princeton Univ., NJ (United States); Fernandes, R. M. [Univ., of Minnesota, Minneapolis, MN (United States); Millis, A. J. [Columbia Univ., New York, NY (United States); Osgood, Jr., R. M. [Columbia Univ., New York, NY (United States); Princeton Univ., Princeton, NJ (United States); Pasupathy, A. N. [Columbia Univ., New York, NY (United States)

    2015-01-01

    We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe?, that we measure by scanning tunneling spectroscopic imaging. We show from the momentum and energy dependence of the quasiparticle interference that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe?. We demonstrate that by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wavevector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiology and the interactions. In 2H-NbSe?, we use this combination to show that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the CDW ordering wave vector.

  6. Quasiparticle interference, quasiparticle interactions, and the origin of the charge density wave in 2H–NbSe2

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

    Arguello, C. J.; Rosenthal, E. P.; Andrade, E. F.; Jin, W.; Yeh, P. C.; Zaki, N.; Jia, S.; Cava, R. J.; Fernandes, R. M.; Millis, A. J.; et al

    2015-01-21

    We show that a small number of intentionally introduced defects can be used as a spectroscopic tool to amplify quasiparticle interference in 2H-NbSe?, that we measure by scanning tunneling spectroscopic imaging. We show from the momentum and energy dependence of the quasiparticle interference that Fermi surface nesting is inconsequential to charge density wave formation in 2H-NbSe?. Thus, we demonstrate that by combining quasiparticle interference data with additional knowledge of the quasiparticle band structure from angle resolved photoemission measurements, one can extract the wavevector and energy dependence of the important electronic scattering processes thereby obtaining direct information both about the fermiologymore »and the interactions. In 2H-NbSe?, we use this combination to show that the important near-Fermi-surface electronic physics is dominated by the coupling of the quasiparticles to soft mode phonons at a wave vector different from the CDW ordering wave vector.« less

  7. High power water load for microwave and millimeter-wave radio frequency sources

    DOE Patents [OSTI]

    Ives, R. Lawrence (Saratoga, CA); Mizuhara, Yosuke M. (Palo Alto, CA); Schumacher, Richard V. (Sunnyvale, CA); Pendleton, Rand P. (Saratoga, CA)

    1999-01-01

    A high power water load for microwave and millimeter wave radio frequency sources has a front wall including an input port for the application of RF power, a cylindrical dissipation cavity lined with a dissipating material having a thickness which varies with depth, and a rear wall including a rotating reflector for the reflection of wave energy inside the cylindrical cavity. The dissipation cavity includes a water jacket for removal of heat generated by the absorptive material coating the dissipation cavity, and this absorptive material has a thickness which is greater near the front wall than near the rear wall. Waves entering the cavity reflect from the rotating reflector, impinging and reflecting multiple times on the absorptive coating of the dissipation cavity, dissipating equal amounts of power on each internal reflection.

  8. A 19.1dBm Segmented Power-Mixer Based Multi-Gbps mm-Wave Transmitter in 32nm SOI CMOS

    E-Print Network [OSTI]

    Hajimiri, Ali

    A 19.1dBm Segmented Power-Mixer Based Multi-Gbps mm-Wave Transmitter in 32nm SOI CMOS Kaushik Abstract -- A high-power, fully-integrated, mm-wave power mixer based transmitter capable of generating case segmentation at 30% higher supply voltage. Index Terms -- mm-wave, , Power Mixer, CMOS Power

  9. Comparison of Energy Efficiency and Power Density in Pressure Retarded Osmosis and Reverse Electrodialysis

    SciTech Connect (OSTI)

    Yip, NY; Elimelech, M

    2014-09-16

    Pressure retarded osmosis (PRO) and reverse electrodialysis (RED) are emerging membrane-based technologies that can convert chemical energy in salinity gradients to useful work. The two processes have intrinsically different working principles: controlled mixing in PRO is achieved by water permeation across salt-rejecting membranes, whereas RED is driven by ion flux across charged membranes. This study compares the energy efficiency and power density performance of PRO and RED with simulated technologically available membranes for natural, anthropogenic, and engineered salinity gradients (seawater-river water, desalination brine-wastewater, and synthetic hypersaline solutions, respectively). The analysis shows that PRO can achieve both greater efficiencies (54-56%) and higher power densities (2.4-38 W/m(2)) than RED (18-38% and 0.77-1.2 W/m(2)). The superior efficiency is attributed to the ability of PRO membranes to more effectively utilize the salinity difference to drive water permeation and better suppress the detrimental leakage of salts. On the other hand, the low conductivity of currently available ion exchange membranes impedes RED ion flux and, thus, constrains the power density. Both technologies exhibit a trade-off between efficiency and power density: employing more permeable but less selective membranes can enhance the power density, but undesired entropy production due to uncontrolled mixing increases and some efficiency is sacrificed. When the concentration difference is increased (i.e., natural -> anthropogenic -> engineered salinity gradients), PRO osmotic pressure difference rises proportionally but not so for RED Nernst potential, which has logarithmic dependence on the solution concentration. Because of this inherently different characteristic, RED is unable to take advantage of larger salinity gradients, whereas PRO power density is considerably enhanced. Additionally, high solution concentrations suppress the Donnan exclusion effect of the charged RED membranes, severely reducing the permselectivity and diminishing the energy conversion efficiency. This study indicates that PRO is more suitable to extract energy from a range of salinity gradients, while significant advancements in ion exchange membranes are likely necessary for RED to be competitive with PRO.

  10. Two-dimensional AXUV-based radiated power density diagnostics on NSTX-U

    SciTech Connect (OSTI)

    Faust, I.; Parker, R. R. [MIT - Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Delgado-Aparicio, L.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; LeBlanc, B.; Kozub, T. A. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Tritz, K. [The Johns Hopkins University, Baltimore, Maryland 21209 (United States); Stratton, B. C. [MIT - Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States)

    2014-11-15

    A new set of radiated-power-density diagnostics for the National Spherical Torus Experiment Upgrade (NSTX-U) tokamak have been designed to measure the two-dimensional poloidal structure of the total photon emissivity profile in order to perform power balance, impurity transport, and magnetohydrodynamic studies. Multiple AXUV-diode based pinhole cameras will be installed in the same toroidal angle at various poloidal locations. The local emissivity will be obtained from several types of tomographic reconstructions. The layout and response expected for the new radially viewing poloidal arrays will be shown for different impurity concentrations to characterize the diagnostic sensitivity. The radiated power profile inverted from the array data will also be used for estimates of power losses during transitions from various divertor configurations in NSTX-U. The effect of in-out and top/bottom asymmetries in the core radiation from high-Z impurities will be addressed.

  11. Journal of Power Sources 153 (2006) 6875 Numerical study of a flat-tube high power density solid oxide fuel cell

    E-Print Network [OSTI]

    2006-01-01

    power density (HPD) solid oxide fuel cell (SOFC) is a geometry based on a tubular type SOFC: Flat-tube; High power density (HPD); Solid oxide fuel cell (SOFC); Simulation; Performance; Optimization 1. Introduction A solid oxide fuel cell (SOFC), like any other fuel cell, produces electrical

  12. High excitation power photoluminescence studies of ultra-low density GaAs quantum dots

    SciTech Connect (OSTI)

    Sonnenberg, D.; Graf, A.; Paulava, V.; Heyn, Ch.; Hansen, W. [Institut für Angewandte Physik und Zentrum für Mikrostrukturforschung, Universität Hamburg, Jungiusstr. 11, 20355 Hamburg (Germany)

    2013-12-04

    We fabricate GaAs epitaxial quantum dots (QDs) by filling of self-organized nanoholes in AlGaAs. The QDs are fabricated under optimized process conditions and have ultra-low density in the 10{sup 6} cm{sup ?2} regime. At low excitation power the optical emission of single QDs exhibit sharp excitonic lines, which are attributed to the recombination of excitonic and biexcitonic states. High excitation power measurements reveal surprisingly broad emission lines from at least six QD shell states.

  13. Primary pump power as a measure of fluid density during bubbly two-phase flow. [PWR

    SciTech Connect (OSTI)

    McCreery, G.E.; Linebarger, J.H.; Koske, J.E.

    1983-01-01

    A nuclear plant operator requires other information on reactor coolant system inventory besides just pressurizer liquid level, which often disappears or gives ambiguous indications during a loss-of-coolant accident. Erroneous instrument readings during the Three Mile Island and Ginna accidents are examples. Pump power or current is shown in this paper to provide an additional source of inventory information. When the reactor coolant pumps are operating, it allows the operator to make decisions about the advisability of continued pump- and safety-injection operation. The inventory information is provided by a simple method of calculating fluid density for bubbly two-phase flow by relating pump power or current to fluid density. The calculational method is derived and compared with data in this paper. Calculations using the method agree well with the measured experimental data with increasing void fraction, until the flow transitions from bubbly to partially stratified churn flow within the pump.

  14. Wave-actuated power take-off device for electricity generation

    SciTech Connect (OSTI)

    Chertok, Allan

    2013-01-31

    Since 2008, Resolute Marine Energy, Inc. (RME) has been engaged in the development of a rigidly moored shallow-water point absorber wave energy converter, the "3D-WEC". RME anticipated that the 3D-WEC configuration with a fully buoyant point absorber buoy coupled to three power take off (PTO) units by a tripod array of tethers would achieve higher power capture than a more conventional 1-D configuration with a single tether and PTO. The investigation conducted under this program and documented herein addressed the following principal research question regarding RME'Â?Â?s power take off (PTO) concept for its 3D-WEC: Is RME's winch-driven generator PTO concept, previously implemented at sub-scale and tested at the Ohmsett wave tank facility, scalable in a cost-effective manner to significant power levels Â?Â?e.g., 10 to 100kW?

  15. An innovative demonstration of high power density in a compact MHD (magnetohydrodynamic) generator

    SciTech Connect (OSTI)

    Schmidt, H.J.; Lineberry, J.T.; Chapman, J.N.

    1990-06-01

    The present program was conducted by the University of Tennessee Space Institute (UTSI). It was by its nature a high risk experimental program to demonstrate the feasibility of high power density operation in a laboratory scale combustion driven MHD generator. Maximization of specific energy was not a consideration for the present program, but the results have implications in this regard by virtue of high energy fuel used. The power density is the ratio of the electrical energy output to the internal volume of the generator channel. The MHD process is a volumetric process and the power density is therefore a direct measure of the compactness of the system. Specific energy, is the ratio of the electrical energy output to consumable energy used for its production. The two parameters are conceptually interrelated. To achieve high power density and implied commensurate low system volume and weight, it was necessary to use an energetic fuel. The high energy fuel of choice was a mixture of powdered aluminum and carbon seeded with potassium carbonate and burned with gaseous oxygen. The solid fuel was burned in a hybrid combustion scheme wherein the fuel was cast within a cylindrical combustor in analogy with a solid propellant rocket motor. Experimental data is limited to gross channel output current and voltage, magnetic field strength, fuel and oxidizer flow rates, flow train external temperatures and combustor pressure. Similarly, while instantaneous oxidizer flow rates were measured, only average fuel consumption based on pre and post test component weights and dimensions was possible. 4 refs., 60 figs., 9 tabs.

  16. Abstract This article will begin by presenting two power take-off (PTO) technologies for the SEAREV wave energy

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    for the SEAREV wave energy converter (WEC) followed by the design methodology applied to electromagnetic with the SEAREV WEC before discussing the two conversion technologies intended to transform wave energy, including one featuring power leveling. Index Terms ­ wave energy conversion - electromagnetic generator

  17. Inflation that runs naturally: Gravitational waves and suppression of power at large and small scales

    E-Print Network [OSTI]

    Quinn E. Minor; Manoj Kaplinghat

    2015-03-08

    We point out three correlated predictions of the axion monodromy inflation model: large amplitude of gravitational waves, suppression of power on horizon scales and on scales relevant for the formation of dwarf galaxies. While these predictions are likely generic to models with oscillations in the inflaton potential, the axion monodromy model naturally accommodates the required running spectral index through Planck-scale corrections to the inflaton potential. Applying this model to a combined data set of Planck, ACT, SPT, and WMAP low-$\\ell$ polarization cosmic microwave background (CMB) data, we find a best-fit tensor-to-scalar ratio $r_{0.05} = 0.07^{+0.05}_{-0.04}$ due to gravitational waves, which may have been observed by the BICEP2 experiment. Despite the contribution of gravitational waves, the total power on large scales (CMB power spectrum at low multipoles) is lower than the standard $\\Lambda$CDM cosmology with a power-law spectrum of initial perturbations and no gravitational waves, thus mitigating some of the tension on large scales. There is also a reduction in the matter power spectrum of 20-30\\% at scales corresponding to $k = 10~{\\rm Mpc}^{-1}$, which are relevant for dwarf galaxy formation. This will alleviate some of the unsolved small-scale structure problems in the standard $\\Lambda$CDM cosmology. The inferred matter power spectrum is also found to be consistent with recent Lyman-$\\alpha$ forest data, which is in tension with the Planck-favored $\\Lambda$CDM model with power-law primordial power spectrum.

  18. Charge-density-wave origin of cuprate checkerboard visualized by scanning tunnelling microscopy

    E-Print Network [OSTI]

    Wise, W. D.

    One of the main challenges in understanding high-Tc superconductivity is to disentangle the rich variety of states of matter that may coexist, cooperate or compete with d-wave superconductivity. At centre stage is the ...

  19. Initial wave packets and the various power-law decreases of scattered wave packets at long times

    E-Print Network [OSTI]

    Manabu Miyamoto

    2004-04-09

    The long time behavior of scattered wave packets $\\psi (x,t)$ from a finite-range potential is investigated, by assuming $\\psi (x,t)$ to be initially located outside the potential. It is then shown that $\\psi (x,t)$ can asymptotically decrease in the various power laws at long time, according to its initial characteristics at small momentum. As an application, we consider the square-barrier potential system and demonstrate that $\\psi (x,t)$ exhibits the asymptotic behavior $t^{-3/2}$, while another behavior like $t^{-5/2}$ can also appear for another $\\psi (x,t)$.

  20. Transport induced by Density Waves in a Andreev-Lifshitz Supersolid

    E-Print Network [OSTI]

    Kwang-Hua W. Chu

    2006-09-03

    Macroscopic derivation of the entrainment in in a Andreev-Lifshitz Supersolid induced by a surface elastic wave propagating along the flexible interface is conducted by considering the nonlinear coupling between the interface and the rarefaction effect. We obtain the critical bounds for zero-volume-flow-rate states corresponding to specific rarefaction measure and wave number which is relevant to the rather small critical velocity of supersolid flows reported by Kim and Chan.

  1. High Power Superconducting Continuous Wave Linacs for Protons and

    Office of Science (SC) Website

    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 Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorkingLosThe23-24, 2011 High Energy Physics AdvisoryScienceHeavy-Ions| U.S.

  2. Low-frequency square-wave electronic ballast with resonant ignition using digital mode and power

    E-Print Network [OSTI]

    Low-frequency square-wave electronic ballast with resonant ignition using digital mode and power both the functions of a resonant circuit for lamp ignition and a current controlled low frequency of the FB converter according to the lamp requirements. I. INTRODUCTION The primary motivation for using low

  3. Power filters for gravitational wave bursts: network operation for source position estimation

    E-Print Network [OSTI]

    Julien Sylvestre

    2003-04-30

    A method is presented to generalize the power detectors for short bursts of gravitational waves that have been developed for single interferometers so that they can optimally process data from a network of interferometers. The performances of this method for the estimation of the position of the source are studied using numerical simulations.

  4. Power Smoothing and Limitation Control of a PMSG-Based Marine Current Turbine under Swell Waves

    E-Print Network [OSTI]

    Boyer, Edmond

    Power Smoothing and Limitation Control of a PMSG-Based Marine Current Turbine under Swell Waves la puissance maximale (MPPT) nécessiterait d'accélérer ou de décélérer fréquemment la turbine à par une turbine marine associée à un générateur synchrone à aimants permanents (GSAP). Un algorithme

  5. Wave goodbye to flat batteries: tiny windmills could power smartphones on the go

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    Wave goodbye to flat batteries: tiny windmills could power smartphones on the go by Matthew Jarvis associate and electrical engineering professor, designed and built the `micro-windmills' as part of a brainstorm commissioned by a Taiwanese firm. "The company was quite surprised with the micro-windmill idea

  6. High-resolution Tangential AXUV Arrays for Radiated Power Density Measurements on NSTX-U

    SciTech Connect (OSTI)

    Delgado-Aparicio, L; Bell, R E; Faust, I; Tritz, K; Diallo, A; Gerhardt, S P; Kozub, T A; LeBlanc, B P; Stratton, B C

    2014-07-01

    Precise measurements of the local radiated power density and total radiated power are a matter of the uttermost importance for understanding the onset of impurity-induced instabilities and the study of particle and heat transport. Accounting of power balance is also needed for the understanding the physics of various divertor con#12;gurations for present and future high-power fusion devices. Poloidal asymmetries in the impurity density can result from high Mach numbers and can impact the assessment of their flux-surface-average and hence vary the estimates of P[sub]rad (r, t) and (Z[sub]eff); the latter is used in the calculation of the neoclassical conductivity and the interpretation of non-inductive and inductive current fractions. To this end, the bolometric diagnostic in NSTX-U will be upgraded, enhancing the midplane coverage and radial resolution with two tangential views, and adding a new set of poloidally-viewing arrays to measure the 2D radiation distribution. These systems are designed to contribute to the near- and long-term highest priority research goals for NSTX-U which will integrate non-inductive operation at reduced collisionality, with high-pressure, long energy-confinement-times and a divertor solution with metal walls.

  7. Theoretical analysis of coupled diffuse-photon-density and thermal-wave field depth profiles photothermally generated in layered turbid dental

    E-Print Network [OSTI]

    Mandelis, Andreas

    -photon-density and thermal-wave model is developed for theoretical analysis of the photothermal field in demineralized teeth. Intact and demineralized layers of enamel, as well as dentin, are described as a layered one

  8. PHYS 211 Lecture 32 Wave power 32 -1 2002 by David Boal, Simon Fraser University. All rights reserved; further copying or resale is strictly prohibited.

    E-Print Network [OSTI]

    Boal, David

    PHYS 211 Lecture 32 ­ Wave power 32 - 1 ©2002 by David Boal, Simon Fraser University. All rights reserved; further copying or resale is strictly prohibited. Lecture 32 ­ Wave power Text: Symon, Mechanics, Chap. 8 Wave power Back in first year, we established that the instantaneous power given by a force F

  9. The desire to achieve both high power density and high power conversion efficiency leads to several required features of a first wall and blanket concept. Achieving high

    E-Print Network [OSTI]

    California at Los Angeles, University of

    required features of a first wall and blanket concept. Achieving high power density means that the coolant wall and blanket design, tritium breeding, activation and waste, power conversion, first wall thermo First wall heat flux 2 MW/m2 Neutron wall load 10 MW/m2 Tritium Breeding Ratio (local 2D) 1.37 Power

  10. Thin-film growth of the charge-density-wave oxide Rb0.30MoO3 H. S. J. van der Zant,a)

    E-Print Network [OSTI]

    Thin-film growth of the charge-density-wave oxide Rb0.30MoO3 H. S. J. van der Zant,a) O. C. Mantel 29 April 1996 We report on the thin-film fabrication of a charge-density wave CDW compound. Single-phase epitaxial films of the model CDW oxide Rb0.30MoO3 have been grown by pulsed-laser deposition. Detailed

  11. Investigation of an improved relativistic backward wave oscillator in efficiency and power capacity

    SciTech Connect (OSTI)

    Song, W.; Chen, C. H.; Sun, J.; Zhang, X. W.; Shao, H.; Song, Z. M.; Huo, S. F.; Shi, Y. C.; Li, X. Z. [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an, Shaanxi 710024 (China)

    2012-10-15

    Investigation of relativistic backward wave oscillator with high efficiency and power capacity is presented in this paper. To obtain high power and high efficiency, a TM{sub 021} mode resonant reflector is used to reduce the pulse shortening and increase power capacity to about 1.7 times. Meanwhile, an extraction cavity at the end of slow wave structure is employed to improve the efficiency from less than 30% to over 40%, through the beam-wave interaction intensification and better energy conversion from modulated electron beam to the electromagnetic field. Consistent with the numerical results, microwave with a power of 3.2 GW, a frequency of 9.75 GHz, and a pulse width of 27 ns was obtained in the high power microwave generation experiment, where the electron beam energy was configured to be {approx}910 kV and its current to be {approx}8.6 kA. The efficiency of the RBWO exceeds 40% at a voltage range of 870 kV-1000 kV.

  12. Progress at the interface of wave-function and density-functional theories

    SciTech Connect (OSTI)

    Gidopoulos, Nikitas I.

    2011-04-15

    The Kohn-Sham (KS) potential of density-functional theory (DFT) emerges as the minimizing effective potential in a variational scheme that does not involve fixing the unknown single-electron density. Using Rayleigh Schroedinger (RS) perturbation theory (PT), we construct ab initio approximations for the energy difference, the minimization of which determines the KS potential directly - thereby bypassing DFT's traditional algorithm to search for the density that minimizes the total energy. From second-order RS PT, we obtain variationally stable energy differences to be minimized, solving the severe problem of variational collapse of orbital-dependent exchange-correlation functionals based on second-order RS PT.

  13. Ferroelectricity Induced by Acentric Spin-Density Waves in YMn{sub 2}O{sub 5}

    SciTech Connect (OSTI)

    Chapon, L.C.; Radaelli, P.G.; Blake, G.R.; Park, S.; Cheong, S.-W.

    2006-03-10

    The commensurate and incommensurate magnetic structures of the magnetoelectric system YMn{sub 2}O{sub 5}, as determined from neutron diffraction, were found to be spin-density waves lacking a global center of symmetry. We propose a model, based on a simple magnetoelastic coupling to the lattice, which enables us to predict the polarization based entirely on the observed magnetic structure. Our data accurately reproduce the temperature dependence of the spontaneous polarization, particularly its sign reversal at the commensurate-incommensurate transition.

  14. Power Corrections and the Gaussian Form of the Meson Wave Function

    E-Print Network [OSTI]

    R. Akhoury; A. Sinkovics; M. G. Sotiropoulos

    1997-10-16

    The wave function of a light pseudoscalar meson is considered and nonperturbative corrections as signaled by perturbation theory are calculated. Two schemes are used, the massive gluon and the running coupling scheme. Both indicate the presence of leading power corrections of ${\\cal O}(b^2)$, whose exponentiation leads to a Gaussian dependence of the wave function on the impact parameter $b$. The dependence of this correction on the light cone energy fractions of the quark and the antiquark is discussed and compared with other models for the meson.

  15. Optimal generalization of power filters for gravitational wave bursts, from single to multiple detectors

    E-Print Network [OSTI]

    Julien Sylvestre

    2003-08-19

    Searches for gravitational wave signals which do not have a precise model describing the shape of their waveforms are often performed using power detectors based on a quadratic form of the data. A new, optimal method of generalizing these power detectors so that they operate coherently over a network of interferometers is presented. Such a mode of operation is useful in obtaining better detection efficiencies, and better estimates of the position of the source of the gravitational wave signal. Numerical simulations based on a realistic, computationally efficient hierarchical implementation of the method are used to characterize its efficiency, for detection and for position estimation. The method is shown to be more efficient at detecting signals than an incoherent approach based on coincidences between lists of events. It is also shown to be capable of locating the position of the source.

  16. Physical interpretation of fractional diffusion-wave equation via lossy media obeying frequency power law

    E-Print Network [OSTI]

    W. Chen; S. Holm

    2003-03-17

    The fractional diffusion-wave equation (FDWE) is a recent generalization of diffusion and wave equations via time and space fractional derivatives. The equation underlies Levy random walk and fractional Brownian motion and is foremost important in mathematical physics for such multidisciplinary applications as in finance, computational biology, acoustics, just to mention a few. Although the FDWE has been found to reflect anomalous energy dissipations, the physical significance of the equation has not been clearly explained in this regard. Here the attempt is made to interpret the FDWE via a new time-space fractional derivative wave equation which models forequency-dependent dissipations observed in such complex phenomena as acoustic wave propagating through human tissues, sediments, and rock layers. Meanwhile, we find a new bound (inequality (6) further below) on the orders of time and space derivatives of the FDWE, which indicates the so-called sub-diffusion process contradicts the real world frequency power law dissipation. This study also shows that the standard approach, albeit mathematically plausible, is phyiscally inappropriate to derive the normal diffusion equation from the damped wave equation, also known as the Telegrapher's equation.

  17. 1204 IEEE JOURNAL OF SOLID-STATE CIRCUITS, VOL. 34, NO. 9, SEPTEMBER 1999 Breakdown in Millimeter-Wave Power InP

    E-Print Network [OSTI]

    del Alamo, Jesús A.

    's) deliver lower output power than GaAs pseudomorphic HEMT's (PHEMT's) throughout most of the millimeter-wave for millimeter-wave power amplification is still a matter of debate. At this time, a review of the literature of merit with which millimeter-wave system designers are concerned. Power-added efficiency (PAE

  18. IMPLEMENTATION OF A FREQUENCY-AGILE,HIGH POWER BACKWARD WAVE OSCILLATOR E. Schamiloglu, C.T. Abdallah, G.T. Park, and V.S. Souvalian

    E-Print Network [OSTI]

    IMPLEMENTATION OF A FREQUENCY-AGILE,HIGH POWER BACKWARD WAVE OSCILLATOR E. Schamiloglu, C demonstrated how finite length effects in a high power vacuum backward wave oscillator (BWO) can be exploited automatically. I. Introduction High-power relativistic backward wave oscillators are considered narrowband

  19. Experimental determination of radiated internal wave power without pressure field data

    SciTech Connect (OSTI)

    Lee, Frank M.; Morrison, P. J. [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States); Paoletti, M. S.; Swinney, Harry L. [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)

    2014-04-15

    We present a method to determine, using only velocity field data, the time-averaged energy flux (J) and total radiated power P for two-dimensional internal gravity waves. Both (J) and P are determined from expressions involving only a scalar function, the stream function ?. We test the method using data from a direct numerical simulation for tidal flow of a stratified fluid past a knife edge. The results for the radiated internal wave power given by the stream function method agree to within 0.5% with results obtained using pressure and velocity data from the numerical simulation. The results for the radiated power computed from the stream function agree well with power computed from the velocity and pressure if the starting point for the stream function computation is on a solid boundary, but if a boundary point is not available, care must be taken to choose an appropriate starting point. We also test the stream function method by applying it to laboratory data for tidal flow past a knife edge, and the results are found to agree with the direct numerical simulation. The supplementary material includes a Matlab code with a graphical user interface that can be used to compute the energy flux and power from two-dimensional velocity field data.

  20. Dust-acoustic waves and stability in the permeating dusty plasma. II. Power-law distributions

    SciTech Connect (OSTI)

    Gong Jingyu; Du Jiulin; Liu Zhipeng

    2012-08-15

    The dust-acoustic waves and the stability theory for the permeating dusty plasma with power-law distributions are studied by using nonextensive q-statistics. In two limiting physical cases, when the thermal velocity of the flowing dusty plasma is much larger than, and much smaller than the phase velocity of the waves, we derived the dust-acoustic wave frequency, the instability growth rate, and the instability critical flowing velocity. As compared with the formulae obtained in part I [Gong et al., Phys. Plasmas 19, 043704 (2012)], all formulae of the present cases and the resulting plasma characteristics are q-dependent, and the power-law distribution of each plasma component of the permeating dusty plasma has a different q-parameter and thus has a different nonextensive effect. Further, we make numerical analyses of an example that a cometary plasma tail is passing through the interplanetary space dusty plasma and we show that these power-law distributions have significant effects on the plasma characteristics of this kind of plasma environment.

  1. Impurity-induced local density of states in a d-wave superconductor carrying a supercurrent 

    E-Print Network [OSTI]

    Zhang, DG; Ting, CS; Hu, Chia-Ren.

    2005-01-01

    and the bias voltage. DOI: 10.1103/PhysRevB.71.064521 PACS numberssd: 74.25.2q, 74.20.2z, 74.62.Dh The understanding of the local physics in cuprate or high- temperature superconductors sHTSd is one of the most chal- lenging problems in condensed matter... predomi- nantly d-wave symmetry.1 The zero-bias conductance peak sZBCPd in the tunneling spectroscopy of normal metal- cuprate superconductor junction with non-sn0md-directional contact provides one of the direct evidences for this symmetry.2 Due...

  2. Power Density Spectra of Gamma-Ray Burst Light Curves: Implications on Theory and Observation

    E-Print Network [OSTI]

    Heon-Young Chang; Insu Yi

    2001-01-02

    We study the power density spectrum (PDS) of artificial light curves of observed gamma-ray bursts (GRBs). We investigate statistical properties of GRB light curves by comparing the reported characteristics in the PDSs of the observed GRBs with those that we model, and discuss implications on interpretations of the PDS analysis results. Results of PDS analysis of observed GRBs suggest that the averaged PDS of GRBs follows a power law over about two decades of frequency with the power law index, -5/3, and the distribution of individual power follows an exponential distribution. Though an attempt to identify the most sensitive physical parameter has been made on the basis of the internal shock model, we demonstrate that conclusions of this kind of approach should be derived with due care. It is indicative that the physical information extracted from the slope can be misleading. We show that the reported slope and the distribution can be reproduced by adjusting the sampling interval in the time domain for a given decaying timescale of individual pulse in a specific form of GRB light curves. In particular, given that the temporal feature is modeled by a two-sided exponential function, the power law behavior with the index of -5/3 and the exponential distribution of the observed PDS is recovered at the 64 ms trigger time scale when the decaying timescale of individual pulse is $\\sim 1$ second, provided that the pulse sharply rises. Another way of using the PDS analysis is an application of the same method to individual long bursts in order to examine a possible evolution of the decaying timescale in a single burst.

  3. Non-intrusive beam power monitor for high power pulsed or continuous wave lasers

    DOE Patents [OSTI]

    Hawsey, Robert A. (Oak Ridge, TN); Scudiere, Matthew B. (Oak Ridge, TN)

    1993-01-01

    A system and method for monitoring the output of a laser is provided in which the output of a photodiode disposed in the cavity of the laser is used to provide a correlated indication of the laser power. The photodiode is disposed out of the laser beam to view the extraneous light generated in the laser cavity whose intensity has been found to be a direct correlation of the laser beam output power level. Further, the system provides means for monitoring the phase of the laser output beam relative to a modulated control signal through the photodiode monitor.

  4. Durability of Low Platinum Fuel Cells Operating at High Power Density

    SciTech Connect (OSTI)

    Polevaya, Olga; Blanchet, Scott; Ahluwalia, Rajesh; Borup, Rod; Mukundan, Rangachary

    2014-03-19

    Understanding and improving the durability of cost-competitive fuel cell stacks is imperative to successful deployment of the technology. Stacks will need to operate well beyond today’s state-of-the-art rated power density with very low platinum loading in order to achieve the cost targets set forth by DOE ($15/kW) and ultimately be competitive with incumbent technologies. An accelerated cost-reduction path presented by Nuvera focused on substantially increasing power density to address non-PGM material costs as well as platinum. The study developed a practical understanding of the degradation mechanisms impacting durability of fuel cells with low platinum loading (?0.2mg/cm2) operating at high power density (?1.0W/cm2) and worked out approaches for improving the durability of low-loaded, high-power stack designs. Of specific interest is the impact of combining low platinum loading with high power density operation, as this offers the best chance of achieving long-term cost targets. A design-of-experiments approach was utilized to reveal and quantify the sensitivity of durability-critical material properties to high current density at two levels of platinum loading (the more conventional 0.45 mgPt.cm–1 and the much lower 0.2 mgPt.cm–2) across several cell architectures. We studied the relevance of selected component accelerated stress tests (AST) to fuel cell operation in power producing mode. New stress tests (NST) were designed to investigate the sensitivity to the addition of electrical current on the ASTs, along with combined humidity and load cycles and, eventually, relate to the combined city/highway drive cycle. Changes in the cathode electrochemical surface area (ECSA) and average oxygen partial pressure on the catalyst layer with aging under AST and NST protocols were compared based on the number of completed cycles. Studies showed elevated sensitivity of Pt growth to the potential limits and the initial particle size distribution. The ECSA loss was correlated with the upper potential limit in the cycle tests, although the performance degradation was found to be a strong function of initial Pt loading. A large fraction of the voltage degradation was found due to increased mass transfer overpotentials, especially in the lower Pt loading cells. Increased mass transfer overpotentials were responsible for a large fraction of the voltage degradation at high current densities. Analysis of the impedance and polarization data indicated O2 diffusion in the aged electrode ionomer to be the main source of the increased mass transfer overpotentials. Results from the experimental parametric studies were used to inform and calibrate newly developed durability model, simulating lifetime performance of the fuel cell under variety of load-cycle protocols, electrode loadings and throughout wide range of operating conditions, including elevated-to-3.0A/cm2 current densities. Complete durability model included several sub-models: platinum dissolution-and-growth as well as reaction-diffusion model of cathode electrode, applied sequentially to study the lifetime predictions of ECSA and polarization performance in the ASTs and NSTs. These models establish relations between changes in overpotentials, ECSA and oxygen mass transport in fuel cell cathodes. The model was calibrated using single cells with land-channel and open flowfield architectures. The model was validated against Nuvera Orion® (open flowfield) short stack data in the load cycle durability tests. The reaction-diffusion model was used to correlate the effective mass transfer coefficients for O2 diffusion in cathode ionomer and separately in gas pores with the operating conditions (pressure, temperature, gas velocity in flow field and current density), Pt loading, and ageing related growth in Pt particles and thinning of the electrode. Achievements of both modeling and experimental objectives were demonstrated in a full format, subscale stacks operating in a simulated but fully realistic ambient environment, using system-compatible operating protocols.

  5. PHYSICAL REVIEW E 86, 046204 (2012) Impedance and power fluctuations in linear chains of coupled wave chaotic cavities

    E-Print Network [OSTI]

    Anlage, Steven

    2012-01-01

    PHYSICAL REVIEW E 86, 046204 (2012) Impedance and power fluctuations in linear chains of coupled wave chaotic cavities Gabriele Gradoni,* Thomas M. Antonsen, Jr., and Edward Ott Institute for Research of electromagnetic wave energy through a chain of coupled cavities is considered. The cavities are assumed

  6. Coherent control and time-dependent density functional theory: Towards creation of wave packets by ultrashort laser pulses

    SciTech Connect (OSTI)

    Raghunathan, Shampa; Nest, Mathias [Theoretische Chemie, TU Muenchen, Lichtenbergstr. 4, 85747 Garching (Germany)

    2012-02-14

    Explicitly time-dependent density functional theory (TDDFT) is a formally exact theory, which can treat very large systems. However, in practice it is used almost exclusively in the adiabatic approximation and with standard ground state functionals. Therefore, if combined with coherent control theory, it is not clear which control tasks can be achieved reliably, and how this depends on the functionals. In this paper, we continue earlier work in order to establish rules that answer these questions. Specifically, we look at the creation of wave packets by ultrashort laser pulses that contain several excited states. We find that (i) adiabatic TDDFT only works if the system is not driven too far from the ground state, (ii) the permanent dipole moments involved should not differ too much, and (iii) these results are independent of the functional used. Additionally, we find an artifact that produces fluence-dependent excitation energies.

  7. Revealing Charge Density Wave Formation in the LaTe2 System byAngle Resolved Photoemission Spectroscopy

    SciTech Connect (OSTI)

    Garcia, D.R.; Gweon, G.-H.; Zhou, S.Y.; Graf, J.; Jozwiak, C.M.; Jung, M.H.; Kwon, Y.S.; Lanzara, A.

    2006-11-15

    We present the first direct study of charge density wave(CDW) formation in quasi-2D single layer LaTe2 using high-resolutionangle resolved photoemission spectroscopy (ARPES) and low energy electrondiffraction (LEED). CDW formation is driven by Fermi surface (FS)nesting, however characterized by a surprisingly smaller gap (~;50 meV)than seen in the double layer RTe3 compounds, extending over the entireFS. This establishes LaTe2 as the first reported semiconducting 2D CDWsystem where the CDW phase is FS nesting driven. In addition, the layerdependence of this phase in the tellurides and the possible transitionfrom a stripe to a checkerboard phase is discussed.

  8. Gamma-ray burst prompt emission light curves and power density spectra in the ICMART model

    SciTech Connect (OSTI)

    Zhang, Bo [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Zhang, Bing, E-mail: bozhang@physics.unlv.edu, E-mail: zhang@physics.unlv.edu [Department of Physics and Astronomy, University of Nevada Las Vegas, Las Vegas, NV 89154 (United States)

    2014-02-20

    In this paper, we simulate the prompt emission light curves of gamma-ray bursts (GRBs) within the framework of the Internal-Collision-induced MAgnetic Reconnection and Turbulence (ICMART) model. This model applies to GRBs with a moderately high magnetization parameter ? in the emission region. We show that this model can produce highly variable light curves with both fast and slow components. The rapid variability is caused by many locally Doppler-boosted mini-emitters due to turbulent magnetic reconnection in a moderately high ? flow. The runaway growth and subsequent depletion of these mini-emitters as a function of time define a broad slow component for each ICMART event. A GRB light curve is usually composed of multiple ICMART events that are fundamentally driven by the erratic GRB central engine activity. Allowing variations of the model parameters, one is able to reproduce a variety of light curves and the power density spectra as observed.

  9. Minimizing lighting power density in office rooms equipped with Anidolic Daylighting Systems

    SciTech Connect (OSTI)

    Linhart, Friedrich; Scartezzini, Jean-Louis [Solar Energy and Building Physics Laboratory (LESO-PB), Ecole Polytechnique Federale de Lausanne (EPFL), 1015 Lausanne (Switzerland)

    2010-04-15

    Electric lighting is responsible for up to one third of an office building's electricity needs. Making daylight more available in office buildings can not only contribute to significant energy savings but also enhance the occupants' performance and wellbeing. Anidolic Daylighting Systems (ADS) are one type of very effective facade-integrated daylighting systems. All south-facing office rooms within the LESO solar experimental building in Lausanne (Switzerland) are equipped with a given type of ADS. A recent study has shown that these offices' occupants are highly satisfied with their lighting environment. The most energy-efficient south-facing offices have a lighting power density of less than 5W/m{sup 2}. The lighting situation within these ''best practice''-offices has been assessed using the lighting simulation software RELUX Vision. Because this lighting situation is very much appreciated by the occupants, it was used as a starting point for developing even more energy-efficient office lighting designs. Two new lighting designs, leading to lighting power densities of 3.9W/m{sup 2} and 3W/m{sup 2}, respectively, have been suggested and simulated with RELUX Vision. Simulation results have shown that the expected performances of these new systems are comparable to that of the current lighting installation within the ''best practice''-offices or even better. These simulation results have been confirmed during experiments on 20 human subjects in a test office room recently set up within the LESO building. This article gives engineers, architects and light planers valuable information and ideas on how to design energy-efficient and comfortable electric lighting systems in office rooms with abundant access to daylight. (author)

  10. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    A review of wave energy converter technology. Proceedings ofdecades. With the technology of wave-energy convert- ers(Wave energy utilization: A review of the technologies. Re-

  11. Unraveling the origin of the pseudogap in a charge density wave compound |

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking With WIPPfinalUnexpectedof Rochester |Argonne National Laboratory

  12. Effect of Chemical Pressure on the Charge Density Wave Transition in

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submitKansas Nuclear Profile 2010MesoscopyStaff »Vehicle automation is aover

  13. Enhanced modified faraday cup for determination of power density distribution of electron beams

    DOE Patents [OSTI]

    Elmer, John W. (Danville, CA); Teruya, Alan T. (Livermore, CA)

    2001-01-01

    An improved tomographic technique for determining the power distribution of an electron or ion beam using electron beam profile data acquired by an enhanced modified Faraday cup to create an image of the current density in high and low power ion or electron beams. A refractory metal disk with a number of radially extending slits, one slit being about twice the width of the other slits, is placed above a Faraday cup. The electron or ion beam is swept in a circular pattern so that its path crosses each slit in a perpendicular manner, thus acquiring all the data needed for a reconstruction in one circular sweep. The enlarged slit enables orientation of the beam profile with respect to the coordinates of the welding chamber. A second disk having slits therein is positioned below the first slit disk and inside of the Faraday cup and provides a shield to eliminate the majority of secondary electrons and ions from leaving the Faraday cup. Also, a ring is located below the second slit disk to help minimize the amount of secondary electrons and ions from being produced. In addition, a beam trap is located in the Faraday cup to provide even more containment of the electron or ion beam when full beam current is being examined through the center hole of the modified Faraday cup.

  14. Femtosecond x-rays link melting of charge density wave correlations and light-enhanced coherent transport in YBa?Cu?O?.?

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

    Forst, M. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Hill, J. P. [Brookhaven National Lab. (BNL), Upton, NY (United States); Frano, A. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Helmholtz-Zentrum Berlin Fur Materialien und Energie, Berlin (Germany); Kaiser, S. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Mankowsky, R. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Hunt, C. R. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Univ. of Illinois at Urbana-Champaign, Urbana, IL (United States); Turner, J. J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Dakovski, G. L. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Minitti, M. P. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Robinson, J. [SLAC National Accelerator Lab., Menlo Park, CA (United States); Loew, T. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Le Tacon, M. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Keimer, B. [Max-Planck Inst. for Solid State Research, Stuttgart (Germany); Cavalleri, A. [Max-Planck Inst. for the Structure and Dynamics of Matter, Hamburg (Germany); Univ. of Oxford (United Kingdom); Dhesi, S. S. [Diamond Light Source, Chilton, Didcot (United Kingdom)

    2014-11-01

    We use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  15. Femtosecond x rays link melting of charge-density wave correlations and light-enhanced coherent transport in YBa2Cu3O6.6

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

    Först, M.; Frano, A.; Kaiser, S.; Mankowsky, R.; Hunt, C. R.; Turner, J. J.; Dakovski, G. L.; Minitti, M. P.; Robinson, J.; Loew, T.; et al

    2014-11-17

    In this study, we use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  16. Femtosecond x-rays link melting of charge density wave correlations and light-enhanced coherent transport in YBa?Cu?O?.?

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

    Forst, M.; Hill, J. P.; Frano, A.; Kaiser, S.; Mankowsky, R.; Hunt, C. R.; Turner, J. J.; Dakovski, G. L.; Minitti, M. P.; Robinson, J.; et al

    2014-11-17

    We use femtosecond resonant soft x-ray diffraction to measure the optically stimulated ultrafast changes of charge density wave correlations in underdoped YBa?Cu?O?.?. We find that when coherent interlayer transport is enhanced by optical excitation of the apical oxygen distortions, at least 50% of the in-plane charge density wave order is melted. These results indicate that charge ordering and superconductivity may be competing up to the charge ordering transition temperature, with the latter becoming a hidden phase that is accessible only by nonlinear phonon excitation.

  17. On line power spectra identification and whitening for the noise in interferometric gravitational wave detectors

    E-Print Network [OSTI]

    E. Cuoco; G. Calamai; L. Fabbroni; G. Losurdo; M. Mazzoni; R. Stanga; F. Vetrano

    2001-04-26

    In this paper we address both to the problem of identifying the noise Power Spectral Density of interferometric detectors by parametric techniques and to the problem of the whitening procedure of the sequence of data. We will concentrate the study on a Power Spectral Density like the one of the Italian-French detector VIRGO and we show that with a reasonable finite number of parameters we succeed in modeling a spectrum like the theoretical one of VIRGO, reproducing all its features. We propose also the use of adaptive techniques to identify and to whiten on line the data of interferometric detectors. We analyze the behavior of the adaptive techniques in the field of stochastic gradient and in the Least Squares ones.

  18. Experimental determination of radiated internal wave power without pressure field data Frank M. Lee, M. S. Paoletti, Harry L. Swinney, and P. J. Morrison

    E-Print Network [OSTI]

    Experimental determination of radiated internal wave power without pressure field data Frank M. Lee Articles you may be interested in Internal wave and boundary current generation by tidal flow over) Experimental determination of radiated internal wave power without pressure field data Frank M. Lee,1 M. S

  19. 670 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 18, NO. 2, MARCH 2003 Integrated Magnetic Full Wave Converter With

    E-Print Network [OSTI]

    Lehman, Brad

    of these circuits are being proposed in 30 W 100 W range, and have great potential for telecommunication power670 IEEE TRANSACTIONS ON POWER ELECTRONICS, VOL. 18, NO. 2, MARCH 2003 Integrated Magnetic Full Wave Converter With Flexible Output Inductor Liang Yan, Student Member, IEEE, Dayu Qu, Member, IEEE

  20. 2/1/2014 geddem.com Wave Your iPhone for Power (Carefully): Micro-Windmill Technology http://www.geddem.com/2014/01/15/wave-your-iphone-for-power-carefully-micro-windmill-technology/ 1/3

    E-Print Network [OSTI]

    Chiao, Jung-Chih

    2/1/2014 geddem.com » Wave Your iPhone for Power (Carefully): Micro-Windmill Technology http://www.geddem.com/2014/01/15/wave-your-iphone-for-power-carefully-micro-windmill-technology/ 1/3 Search here Subscribe (300) Tech (150) Gaming (5) Websites (23) Wave Your iPhone for Power (Carefully): Micro-Windmill

  1. Decay estimates for One-dimensional wave equations with inverse power potentials

    E-Print Network [OSTI]

    O. Costin; M. Huang

    2014-10-23

    We study the one-dimensional wave equation with an inverse power potential that equals $const.x^{-m}$ for large $|x|$ where $m$ is any positive integer greater than or equal to 3. We show that the solution decays pointwise like $t^{-m}$ for large $t$, which is consistent with existing mathematical and physical literature under slightly different assumptions (see e.g. Bizon, Chmaj, and Rostworowski, 2007; Donninger and Schlag, 2010; Schlag, 2007). Our results can be generalized to potentials consisting of a finite sum of inverse powers, the largest of which being $const.x^{-\\alpha}$ where $\\alpha>2$ is a real number, as well as potentials of the form $const.x^{-m}+O(x^{-m-\\delta_1})$ with $\\delta_1>3$.

  2. High-Harmonic Fast-Wave Power Flow Along Magnetic Field Lines in the Scrape-Off Layer of NSTX

    SciTech Connect (OSTI)

    Perkins, R. J. [Princeton Plasma Physics Laboratory (PPPL); Hosea, J. [Princeton Plasma Physics Laboratory (PPPL); Kramer, G. [Princeton Plasma Physics Laboratory (PPPL); Ahn, Joonwook [ORNL; Bell, R. E. [Princeton Plasma Physics Laboratory (PPPL); Diallo, A. [Princeton Plasma Physics Laboratory (PPPL); Gerhardt, S. [Princeton Plasma Physics Laboratory (PPPL); Gray, T. K. [Oak Ridge National Laboratory (ORNL); Green, David L [ORNL; Jaeger, Erwin Frederick [ORNL; Jaworski, M. A. [Princeton Plasma Physics Laboratory (PPPL); LeBlanc, B [Princeton Plasma Physics Laboratory (PPPL); McLean, Adam G [ORNL; Maingi, Rajesh [ORNL; Phillips, C. K. [Princeton Plasma Physics Laboratory (PPPL); Roquemore, L. [Princeton Plasma Physics Laboratory (PPPL); Ryan, Philip Michael [ORNL; Sabbagh, S. A. [Columbia University; Taylor, G. [Princeton Plasma Physics Laboratory (PPPL); Wilson, J. R. [Princeton Plasma Physics Laboratory (PPPL)

    2012-01-01

    A significant fraction of high-harmonic fast-wave (HHFW) power applied to NSTX can be lost to the scrape-off layer (SOL) and deposited in bright and hot spirals on the divertor rather than in the core plasma. We show that the HHFW power flows to these spirals along magnetic field lines passing through the SOL in front of the antenna, implying that the HHFW power couples across the entire width of the SOL rather than mostly at the antenna face. This result will help guide future efforts to understand and minimize these edge losses in order to maximize fast-wave heating and current drive.

  3. Powerful High Velocity-Dispersion Molecular Hydrogen Associated with an Intergalactic Shock Wave in Stephan's Quintet

    E-Print Network [OSTI]

    P. N. Appleton; K. C. Xu; W. Reach; M. A. Dopita; Y. Gao; N. Lu; C. C. Popescu; J. W. Sulentic; R. J. Tuffs; M. S. Yun

    2006-02-25

    We present the discovery of strong mid-infrared emission lines of molecular hydrogen of apparently high velocity dispersion (~870 km/s) originating from a group-wide shock wave in Stephan's Quintet. These Spitzer Space Telescope observations reveal emission lines of molecular hydrogen and little else. this is the first time an almost pure H_2 line spectrum has been seen in an extragalactic object. Along with the absence of PAH features and very low excitation ionized gas tracers, the spectra resemble shocked gas seen in Galactic supernova remnants, but on a vast scale. The molecular emission extends over 24 kpc along the X-ray emitting shock-front, but has ten times the surface luminosity as the soft X-rays, and about one-third the surface luminosity of the IR continuum. We suggest that the powerful H_2 emission is generated by the shock wave caused when a high-velocity intruder galaxy collides with filaments of gas in the galaxy group. Our observations suggest a close connection between galaxy-scale shock-waves and strong broad H_2 emission lines, like those seen in the spectra of Ultraluminous Infrared Galaxies where high-speed collisions between galaxy disks are common.

  4. Low power penalty 80 to 10 Gbit/s OTDM demultiplexer using standing-wave enhanced electroabsorption modulator with reduced driving voltage

    E-Print Network [OSTI]

    2003-01-01

    ratio and saturation power traveling-wave electroabsorptionpower penalty 80 t o 10 Gbit/s OTDM demultiplexer using standing-wavepower penalty 80 to l O G b i l / s demultiplexing using a novel standing-wave

  5. Journal of Power Sources 140 (2005) 331339 Numerical study of a flat-tube high power density solid oxide fuel cell

    E-Print Network [OSTI]

    2005-01-01

    ) solid oxide fuel cell (SOFC) is a new design developed by Siemens Westinghouse, based on their formerly.V. All rights reserved. Keywords: Flat-tube; High power density; Solid oxide fuel cell; Simulation; Heat oxide fuel cell Part I. Heat/mass transfer and fluid flow Yixin Lu1, Laura Schaefer, Peiwen Li2

  6. Potential order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind

    E-Print Network [OSTI]

    Dabiri, John O.

    Potential order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind turbine arrays John O. Dabiria) Graduate Aeronautical Laboratories and Bioengineering, California; published online 19 July 2011) Modern wind farms comprised of horizontal-axis wind turbines (HAWTs) require

  7. Spectral Densities and Frequencies in the Power Spectrum of Higher Order Repeat Alpha Satellite in Human DNA Molecule*

    E-Print Network [OSTI]

    Pavin, Nenad

    Spectral Densities and Frequencies in the Power Spectrum of Higher Order Repeat Alpha Satellite in Human DNA Molecule* Vladimir Paar,a,** Nenad Pavin,a Ivan Basar,a Marija Rosandi},b Ivica Luketin was applied to the central segment of a fully sequenced genomic seg- ment from the centromeric region in human

  8. Ultralow-power local laser control of the dimer density in alkali-metal vapors through photodesorption

    SciTech Connect (OSTI)

    Jha, Pankaj K.; Scully, Marlan O. [Texas A and M University, College Station, Texas 77843 (United States); Princeton University, Princeton, New Jersey 08544 (United States); Dorfman, Konstantin E. [Texas A and M University, College Station, Texas 77843 (United States); University of California, Irvine, Irvine, California 92697 (United States); Yi Zhenhuan; Yuan Luqi; Welch, George R. [Texas A and M University, College Station, Texas 77843 (United States); Sautenkov, Vladimir A. [Texas A and M University, College Station, Texas 77843 (United States); Joint Institute of High Temperature, RAS, Moscow 125412 (Russian Federation); Rostovtsev, Yuri V. [University of North Texas, Denton, Texas 76203 (United States); Zheltikov, Aleksei M. [Texas A and M University, College Station, Texas 77843 (United States); M.V. Lomonosov Moscow State University, Moscow 119992 (Russian Federation)

    2012-08-27

    Ultralow-power diode-laser radiation is employed to induce photodesorption of cesium from a partially transparent thin-film cesium adsorbate on a solid surface. Using resonant Raman spectroscopy, we demonstrate that this photodesorption process enables an accurate local optical control of the density of dimer molecules in alkali-metal vapors.

  9. Emergence of coherence in the charge-density wave state of 2H-NbSe2

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

    Chatterjee, U.; Zhao, J.; Iavarone, M.; Di Capua, R.; Castellan, J. P.; Karapetrov, G.; Malliakas, C. D.; Kanatzidis, M. G.; Claus, H.; Ruff, J. P. C.; et al

    2015-02-17

    A charge-density wave (CDW) state has a broken symmetry described by a complex order parameter with an amplitude and a phase. The conventional view, based on clean, weak-coupling systems, is that a finite amplitude and long-range phase coherence set in simultaneously at the CDW transition temperature Tcdw. Here we investigate, using photoemission, X-ray scattering and scanning tunnelling microscopy, the canonical CDW compound 2H-NbSe2 intercalated with Mn and Co, and show that the conventional view is untenable. We find that, either at high temperature or at large intercalation, CDW order becomes short-ranged with a well-defined amplitude, which has impacts on themore »electronic dispersion, giving rise to an energy gap. The phase transition at Tcdw marks the onset of long-range order with global phase coherence, leading to sharp electronic excitations. Our observations emphasize the importance of phase fluctuations in strongly coupled CDW systems and provide insights into the significance of phase incoherence in ‘pseudogap’ states.« less

  10. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    A review of wave energy converter technology. Proceedings ofWave energy utilization: A review of the technologies. Re-decades. With the technology of wave-energy convert- ers(

  11. Power Maximization in Wave-Energy Converters Using Sampled -Data Extremum Seeking /

    E-Print Network [OSTI]

    Chen, Tianjia

    2013-01-01

    design optimization of wave energy converters con- sistingN. Sahinkaya. A review of wave energy converter technology.2009. [6] A.F.O. Falc˜ao. Wave energy utilization: A review

  12. Fast-wave Power Flow Along SOL Field Lines In NSTX nd The Associated Power Deposition Profile Across The SOL In Front Of The Antenna

    SciTech Connect (OSTI)

    Perkins, Roy

    2013-06-21

    Fast-wave heating and current drive efficiencies can be reduced by a number of processes in the vicinity of the antenna and in the scrape off layer (SOL). On NSTX from around 25% to more than 60% of the high-harmonic fast-wave power can be lost to the SOL regions, and a large part of this lost power flows along SOL magnetic field lines and is deposited in bright spirals on the divertor floor and ceiling. We show that field-line mapping matches the location of heat deposition on the lower divertor, albeit with a portion of the heat outside of the predictions. The field-line mapping can then be used to partially reconstruct the profile of lost fast-wave power at the midplane in front of the antenna, and the losses peak close to the last closed flux surface (LCFS) as well as the antenna. This profile suggests a radial standing-wave pattern formed by fast-wave propagation in the SOL, and this hypothesis will be tested on NSTX-U. Advanced RF codes must reproduce these results so that such codes can be used to understand this edge loss and to minimize RF heat deposition and erosion in the divertor region on ITER.

  13. Mesoscopic Charge Density Wave

    E-Print Network [OSTI]

    technology . . . . . . . . . . . . . . . . . . . . . . 10 1.3.1 Thin lms of Rb0:30MoO3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 2 Thin Rb0:30MoO3 lms by pulsed-laser deposition 23 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 3.2 Thin lms of Rb0:30MoO3 . . . . . . . . . . . . . . . . . . . . . . 44 3.3 Fabrication of Rb0

  14. Charge Density Wave Compounds

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 OutreachProductswsicloudwsiclouddenDVA N C E D BGene Network ShapingDate:Characterization

  15. Influence of fluid density on the statistics of power fluctuations in von K\\'arm\\'an swirling flows

    E-Print Network [OSTI]

    Opazo, A; Bustamante, G; Labbé, R

    2015-01-01

    We report experimental results for fluctuations of injected power in confined von K\\'arm\\'an swirling flows with constant external torque applied to the stirrers. Two experiments were performed at nearly equal Reynolds numbers in geometrically similar experimental setups, using air in one of them and water in the other. We found that the probability density function of power fluctuations is strongly asymmetric in air, while in water it is closer to a Gaussian, showing that the effect that a big change on the fluid density has on the flow-stirrer interaction is not reflected merely by a change in the amplitude of stirrers' response. In the case of water, with a density roughly 830 times greater than air density, the forcing exerted by the flow on the stirrers is stronger, so that they follow more closely the locally averaged rotation of the flow. When the fluid is air, the forcing is much weaker, resulting not only in a smaller stirrer response to the torque exerted by the flow, but also in power fluctuations ...

  16. The constraints on power spectrum of relic gravitational waves from current observations of large-scale structure of the Universe

    E-Print Network [OSTI]

    B. Novosyadlyj; S. Apunevych

    2004-12-02

    We carry out the determination of the amplitude of relic gravitational waves power spectrum. Indirect best-fit technique was applied to compare observational data and theory predictions. As observations we have used data on large-scale structure (LSS) of the Universe and anisotropy of cosmic microwave background (CMB) temperature. The conventional inflationary model with 11 parameters has been investigated, all of them evaluated jointly. This approach gave us a possibility to find parameters of power spectrum of gravitational waves along with statistical errors. The main result consists in following: WMAP data on power spectrum of CMB temperature fluctuations along with LSS data prefer model with small amplitude of tensor mode power spectrum, close to zero. The upper limit for its amplitude at quadupole harmonics T/S=0.6 at 95% C.L.

  17. DEVELOPMENT OF PTO-SIM: A POWER PERFORMANCE MODULE FOR THE OPEN-SOURCE WAVE ENERGY CONVERTER CODE WEC-SIM

    E-Print Network [OSTI]

    DEVELOPMENT OF PTO-SIM: A POWER PERFORMANCE MODULE FOR THE OPEN-SOURCE WAVE ENERGY CONVERTER CODE National Laboratories Albuquerque, NM USA Email: kelley.ruehl@sandia.gov ABSTRACT WEC-Sim (Wave Energy Converter-SIMulator) is an open- source wave energy converter (WEC) code capable of simulat- ing WECs

  18. Chiral magnetic wave at finite baryon density and the electric quadrupole moment of quark-gluon plasma in heavy ion collisions

    E-Print Network [OSTI]

    Yannis Burnier; Dmitri E. Kharzeev; Jinfeng Liao; Ho-Ung Yee

    2011-03-07

    Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon plasma in the presence of external magnetic field that stems from the interplay of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by the waves of the electric and chiral charge densities coupled by the axial anomaly. We consider CMW at finite baryon density and find that it induces the electric quadrupole moment of the quark-gluon plasma produced in heavy ion collisions: the "poles" of the produced fireball (pointing outside of the reaction plane) acquire additional positive electric charge, and the "equator" acquires additional negative charge. We point out that this electric quadrupole deformation lifts the degeneracy between the elliptic flows of positive and negative pions leading to $v_2(\\pi^+) < v_2(\\pi^-)$, and estimate the magnitude of the effect.

  19. Spin-orbit Coupling Induced Magnetism in the d-density Wave Phase of La2-xBaxCuO4 Superconductors

    SciTech Connect (OSTI)

    Wu, Congjun; /Stanford U., Phys. Dept. /Santa Barbara, KITP; Zaanen, Jan; Zhang, Shou-Cheng; /Stanford U., Phys. Dept.

    2010-01-15

    We study the effects of spin-orbit coupling in the d-density wave (DDW) phase. In the low-temperature orthorhombic phase of La{sub 2-x}Ba{sub x}CuO{sub 4}, we find that spin-orbit coupling induces ferromagnetic moments in the DDW phase, which are polarized along the [110] direction with a considerable magnitude. This effect does not exist in the superconducting phase. On the other hand, if the d-density wave order does not exist at zero field, a magnetic field along the [110] direction always induces such a staggered orbital current. We discuss experimental constraints on the DDW states in light of our theoretical predictions.

  20. High-resolution tangential absolute extreme ultraviolet arrays for radiated power density measurements on NSTX-U

    SciTech Connect (OSTI)

    Delgado-Aparicio, L.; Bell, R. E.; Diallo, A.; Gerhardt, S. P.; Kozub, T. A.; LeBlanc, B. P.; Stratton, B. C. [Princeton Plasma Physics Laboratory, Princeton, New Jersey 08540 (United States); Faust, I. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States); Tritz, K. [The Johns Hopkins University, Baltimore, Maryland 21209 (United States)

    2014-11-15

    The radiated-power-density diagnostic on the equatorial midplane for the NSTX-U tokamak will be upgraded to measure the radial structure of the photon emissivity profile with an improved radial resolution. This diagnostic will enhance the characterization and studies of power balance, impurity transport, and MHD. The layout and response expected of the new system is shown for different plasma conditions and impurity concentrations. The effect of toroidal rotation driving poloidal asymmetries in the core radiation from high-Z impurities is also addressed.

  1. Nuclear Instruments and Methods in Physics Research A 547 (2005) 663678 Determining axial fuel-rod power-density profiles from in-core

    E-Print Network [OSTI]

    Shultis, J. Kenneth

    2005-01-01

    is proposed for determining power-density profiles in nuclear reactor fuel rods from neutron flux measurementsNuclear Instruments and Methods in Physics Research A 547 (2005) 663­678 Determining axial fuel-rod power-density profiles from in-core neutron flux measurements J. Kenneth Shultisà Department

  2. High-Temperature SiC Power Module with Integrated SiC Gate Drivers for Future High-Density Power Electronics Applications

    SciTech Connect (OSTI)

    Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.; Passmore, Mr. Brandon [APEI, Inc.; Martin, Daniel [APEI, Inc.; Mcnutt, Tyler [APEI, Inc.; Lostetter, Dr. Alex [APEI, Inc.; Ericson, Milton Nance [ORNL; Frank, Steven Shane [ORNL; Britton Jr, Charles L [ORNL; Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Dr. Matt [University of Arkansas; Lamichhane, Ranjan [University of Arkansas; Shepherd, Dr. Paul [University of Arkansas; Glover, Dr. Michael [University of Arkansas

    2015-01-01

    This paper presents the testing results of an all-silicon carbide (SiC) intelligent power module (IPM) for use in future high-density power electronics applications. The IPM has high-temperature capability and contains both SiC power devices and SiC gate driver integrated circuits (ICs). The high-temperature capability of the SiC gate driver ICs allows for them to be packaged into the power module and be located physically close to the power devices. This provides a distinct advantage by reducing the gate driver loop inductance, which promotes high frequency operation, while also reducing the overall volume of the system through higher levels of integration. The power module was tested in a bridgeless-boost converter to showcase the performance of the module in a system level application. The converter was initially operated with a switching frequency of 200 kHz with a peak output power of approximately 5 kW. The efficiency of the converter was then evaluated experimentally and optimized by increasing the overdrive voltage on the SiC gate driver ICs. Overall a peak efficiency of 97.7% was measured at 3.0 kW output. The converter s switching frequency was then increased to 500 kHz to prove the high frequency capability of the power module was then pushed to its limits and operated at a switching frequency of 500 kHz. With no further optimization of components, the converter was able to operate under these conditions and showed a peak efficiency of 95.0% at an output power of 2.1 kW.

  3. A Predictive power control of Doubly Fed Induction Generator for Wave Energy Converter

    E-Print Network [OSTI]

    Brest, Université de

    Switchgear Wave converter control Gear hal-01023509,version1-13Jul2014 Author manuscript, published in "IEEE

  4. Density-potential pairs for spherical stellar systems with Sersic light-profiles and (optional) power-law cores

    E-Print Network [OSTI]

    Balsa Terzic; Alister W. Graham

    2005-06-10

    Popular models for describing the luminosity-density profiles of dynamically hot stellar systems (e.g., Jaffe, Hernquist, Dehnen) were constructed with the desire to match the deprojected form of an R^{1/4} light-profile. Real galaxies, however, are now known to have a range of different light-profile shapes that scale with mass. Consequently, although highly useful, the above models have implicit limitations, and this is illustrated here through their application to a number of real galaxy density profiles. On the other hand, the analytical density profile given by Prugniel & Simien (1997) closely matches the deprojected form of Sersic R^{1/n} light-profiles - including deprojected exponential light-profiles. It is thus applicable for describing bulges in spiral galaxies, dwarf elliptical galaxies, and both ordinary and giant elliptical galaxies. Here we provide simple equations, in terms of elementary and special functions, for the gravitational potential and force associated with this density profile. Furthermore, to match galaxies with partially depleted cores, and better explore the supermassive black hole / galaxy connection, we have added a power-law core to this density profile and derived similar expressions for the potential and force of this hybrid profile. Expressions for the mass and velocity dispersion, assuming isotropy, are also given. These models may also prove appropriate for describing the dark matter distribution in halos formed from LCDM cosmological simulations.

  5. Wave

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power AdministrationRobust,Field-effectWorking WithTelecentricN AProject Assessment Customer5-259011 Summer 2001 Heat

  6. High Power Millimeter-Wave Signal Generation in Advanced SiGe and CMOS Process

    E-Print Network [OSTI]

    Lin, Hsin-Chang

    2015-01-01

    2.4.2 Power Measurements . . . . . . . . . . . . . . . . .2.3.2 8-way Power Combining . . . . . . . . . . . . . . .2.3.3 16-way Power Combining . . . . .

  7. The Effect of Vegetation Density on the Resilience of Coastal Dune Systems Against Wave-Induced Erosion 

    E-Print Network [OSTI]

    Tyler, Robert Cory

    2013-09-28

    by coastal managers and stakeholders. Dunes with healthy vegetation growth are believed to provide an even higher resilience against wave-induced erosion. However, very little research currently exists on quantifying the effect that plants have on dune...

  8. Thermal Properties of Graphene and Applications for Thermal Management of High-Power Density Electronics

    E-Print Network [OSTI]

    Yan, Zhong

    2013-01-01

    Turin and A. A. Balandin, Electronics Letters 40, 81 (2004).REFERENCES G. E. Moore, Electronics 38 (1965). E. Pop, Nanofor High-power Electronics” PCSI-38:38th Conference on the

  9. Doped LiFePO? cathodes for high power density lithium ion batteries

    E-Print Network [OSTI]

    Bloking, Jason T. (Jason Thompson), 1979-

    2003-01-01

    Olivine LiFePO4 has received much attention recently as a promising storage compound for cathodes in lithium ion batteries. It has an energy density similar to that of LiCoO 2, the current industry standard for cathode ...

  10. Power Spectrum of the density of cold atomic gas in the Galaxy towards Cas A and Cygnus A

    E-Print Network [OSTI]

    A. A. Deshpande; K. S. Dwarakanath; W. M. Goss

    2000-07-25

    We have obtained the power spectral description of the density and opacity fluctuations of the cold HI gas in the Galaxy towards Cas A, and Cygnus A. We have employed a method of deconvolution, based on CLEAN, to estimate the true power spectrum of optical depth of cold HI gas from the observed distribution, taking into account the finite extent of the background source and the incomplete sampling of optical depth over the extent of the source. We investigate the nature of the underlying spectrum of density fluctuations in the cold HI gas which would be consistent with that of the observed HI optical depth fluctuations. These power spectra for the Perseus arm towards Cas A, and for the Outer arm towards Cygnus A have a slope of 2.75 +/- 0.25 (3sigma error). The slope in the case of the Local arm towards Cygnus A is 2.5, and is significantly shallower in comparison. The linear scales probed here range from 0.01 to 3 pc. We discuss the implications of our results, the non-Kolmogorov nature of the spectrum, and the observed HI opacity variations on small transverse scales.

  11. In recent years, power density in microprocessors has doubled every three years,

    E-Print Network [OSTI]

    Huang, Wei

    faster than operating volt- ages. Because a microprocessor consumes energy and converts it into heat reliability and low manufacturing cost. Any design must remove heat from the surface of the microprocessor die of hundreds of microseconds or mil- liseconds. Power-management techniques, to be useful for thermal

  12. Improved power capacity in a high efficiency klystron-like relativistic backward wave oscillator by distributed energy extraction

    SciTech Connect (OSTI)

    Xiao, Renzhen; Chen, Changhua; Cao, Yibing; Sun, Jun [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China)

    2013-12-07

    With the efficiency increase of a klystron-like relativistic backward wave oscillator, the maximum axial electric field and harmonic current simultaneously appear at the end of the beam-wave interaction region, leading to a highly centralized energy exchange in the dual-cavity extractor and a very high electric field on the cavity surface. Thus, we present a method of distributed energy extraction in this kind of devices. Particle-in-cell simulations show that with the microwave power of 5.1?GW and efficiency of 70%, the maximum axial electric field is decreased from 2.26 MV/cm to 1.28 MV/cm, indicating a threefold increase in the power capacity.

  13. Topographic power spectral density study of the effect of surface treatment processes on niobium for superconducting radio frequency accelerator cavities

    SciTech Connect (OSTI)

    Charles Reece, Hui Tian, Michael Kelley, Chen Xu

    2012-04-01

    Microroughness is viewed as a critical issue for attaining optimum performance of superconducting radio frequency accelerator cavities. The principal surface smoothing methods are buffered chemical polish (BCP) and electropolish (EP). The resulting topography is characterized by atomic force microscopy (AFM). The power spectral density (PSD) of AFM data provides a more thorough description of the topography than a single-value roughness measurement. In this work, one dimensional average PSD functions derived from topography of BCP and EP with different controlled starting conditions and durations have been fitted with a combination of power law, K correlation, and shifted Gaussian models to extract characteristic parameters at different spatial harmonic scales. While the simplest characterizations of these data are not new, the systematic tracking of scale-specific roughness as a function of processing is new and offers feedback for tighter process prescriptions more knowledgably targeted at beneficial niobium topography for superconducting radio frequency applications.

  14. Alpha Power Channeling with Two Waves N. J. Fisch and M. C. Herrmann

    E-Print Network [OSTI]

    DIFFUSION TO ONE DIMENSION The energy of the -particles is best tapped by dif- fusing them in energy Laboratory Princeton, NJ 08543, USA ABSTRACT. The complete channeling of energy from alpha particles. While one wave constrains more firmly the direction of the energy transfer, the necessary wave

  15. Exploring finite density QCD phase transition with canonical approach -Power of multiple precision computation-

    E-Print Network [OSTI]

    Shotaro Oka; for Zn-Collaboration

    2015-11-15

    The canonical approach for finite density lattice QCD has a numerical instability. This instability makes it difficult to use the method reliably at the finite real chemical potential region. We studied this instability in detail and found that it is caused by the cancellation of significant digits. In order to reduce the effect of this cancellation, we adopt the multiple precision calculation for our discrete Fourier transformation (DFT) program, and we get the canonical partition function Zc(n,T) with required accuracy. From the obtained Zc(n,T), we calculate Lee--Yang zero distribution varying the number of significant digits. As a result, some curves surround the origin in the fugacity plane, but they are moved by varying the number of significant digits. Hence, we conclude that these curves are pseudo phase transition lines, and not real ones.

  16. An Open Ocean Trial of Controlled Upwelling Using Wave Pump Technology ANGELICQUE WHITE

    E-Print Network [OSTI]

    White, Angelicque

    An Open Ocean Trial of Controlled Upwelling Using Wave Pump Technology ANGELICQUE WHITE College) ABSTRACT In 1976, John D. Isaacs proposed to use wave energy to invert the density structure of the ocean of deep water to the surface ocean. Although Isaacs's wave-powered pump has taken many forms, from energy

  17. MEMS Fuel Cells--Low Temp--High Power Density - Energy Innovation Portal

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousandReport) | SciTech ConnectFuture3, Washington,AMONG THE

  18. Early structure formation from primordial density fluctuations with a blue-tilted power spectrum

    E-Print Network [OSTI]

    Hirano, Shingo; Yoshida, Naoki; Spergel, David; Yorke, Harold W

    2015-01-01

    While observations of large-scale structure and the cosmic microwave background (CMB) provide strong constraints on the amplitude of the primordial power spectrum (PPS) on scales larger than 10 Mpc, the amplitude of the power spectrum on sub-galactic length scales is much more poorly constrained. We study early structure formation in a cosmological model with a blue-tilted PPS. We assume that the standard scale-invariant PPS is modified at small length scales as $P(k) \\sim k^{m_{\\rm s}}$ with $m_{\\rm s} > 1$. We run a series of cosmological hydrodynamic simulations to examine the dependence of the formation epoch and the characteristic mass of primordial stars on the tilt of the PPS. In models with $m_{\\rm s} > 1$, star-forming gas clouds are formed at $z > 100$, when formation of hydrogen molecules is inefficient because the intense CMB radiation destroys chemical intermediates. Without efficient coolant, the gas clouds gravitationally contract while keeping a high temperature. The protostars formed in such ...

  19. ISET Journal of Earthquake Technology, Paper No. 487, Vol. 44, No. 1, March 2007, pp. 305323 ENERGY AND POWER OF NONLINEAR WAVES IN A SEVEN-STORY

    E-Print Network [OSTI]

    Gupta, Vinay Kumar

    variations of wave energy and of power in the building response, and to set a physical basis for a new designISET Journal of Earthquake Technology, Paper No. 487, Vol. 44, No. 1, March 2007, pp. 305

  20. Status of Wave and Tidal Power Technologies for the United States

    SciTech Connect (OSTI)

    Musial, W.

    2008-08-01

    This paper presents the status of marine applications for renewable energy as of 2008 from a U.S. perspective. Technologies examined include wave, tidal, and ocean current energy extraction devices.

  1. High Current Density, Long Life Cathodes for High Power RF Sources

    SciTech Connect (OSTI)

    Ives, Robert Lawrence; Collins, George; Falce, Lou; Schwartzkopf, Steve; Busbaher, Daniel

    2014-01-22

    This program was tasked with improving the quality and expanding applications for Controlled Porosity Reservoir (CPR) cathodes. Calabazas Creek Research, Inc. (CCR) initially developed CPR cathodes on a DOE-funded SBIR program to improve cathodes for magnetron injection guns. Subsequent funding was received from the Defense Advanced Research Projects Agency. The program developed design requirements for implementation of the technology into high current density cathodes for high frequency applications. During Phase I of this program, CCR was awarded the prestigious 2011 R&D100 award for this technology. Subsequently, the technology was presented at numerous technical conferences. A patent was issued for the technology in 2009. These cathodes are now marketed by Semicon Associates, Inc. in Lexington, KY. They are the world’s largest producer of cathodes for vacuum electron devices. During this program, CCR teamed with Semicon Associates, Inc. and Ron Witherspoon, Inc. to improve the fabrication processes and expand applications for the cathodes. Specific fabrications issues included the quality of the wire winding that provides the basic structure and the sintering to bond the wires into a robust, cohesive structure. The program also developed improved techniques for integrating the resulting material into cathodes for electron guns.

  2. Partial wave analysis at BES III harnessing the power of GPUs

    E-Print Network [OSTI]

    Niklaus Berger

    2011-08-29

    Partial wave analysis is a core tool in hadron spectroscopy. With the high statistics data available at facilities such as the Beijing Spectrometer III, this procedure becomes computationally very expensive. We have successfully implemented a framework for performing partial wave analysis on graphics processors. We discuss the implementation, the parallel computing frameworks employed and the performance achieved, with a focus on the recent transition to the OpenCL framework.

  3. Order-of-magnitude enhancement of wind farm power density via counter-rotating vertical-axis wind turbine arrays

    E-Print Network [OSTI]

    Dabiri, John O

    2010-01-01

    Modern wind farms require significant land resources to separate each wind turbine from the adjacent turbine wakes. These aerodynamic constraints limit the amount of power that can be extracted from a given wind farm footprint. We conducted full-scale field tests of vertical-axis wind turbines in counter-rotating configurations under natural wind conditions. Whereas wind farms consisting of propeller-style turbines produce 2 to 3 watts of power per square meter of land area, these field tests indicate that power densities approaching 100 W m^-2 can be achieved by arranging vertical-axis wind turbines in layouts that enable them to extract energy from adjacent wakes. In addition, we calculated that the global wind resource available to 10-m tall turbines based on the present approach is approximately 225 trillion watts (TW), which significantly exceeds the global wind resource available to 80-m tall, propeller-style wind turbines, approximately 75 TW. This improvement is due to the closer spacing that can be a...

  4. Spatial and temporal modulation of internal waves and thermohaline structure

    E-Print Network [OSTI]

    Cole, Sylvia T.

    2010-01-01

    of outward internal wave energy and dissipation was 17 GW.between internal wave energy density, energy flux, andstructure of internal wave energy density, energy flux, and

  5. Cyclic voltammetry on sputter-deposited films of electrochromic Ni oxide: Power-law decay of the charge density exchange

    SciTech Connect (OSTI)

    Wen, Rui-Tao Granqvist, Claes G.; Niklasson, Gunnar A.

    2014-10-20

    Ni-oxide-based thin films were produced by reactive direct-current magnetron sputtering and were characterized by X-ray diffraction and Rutherford backscattering spectroscopy. Intercalation of Li{sup +} ions was accomplished by cyclic voltammetry (CV) in an electrolyte of LiClO{sub 4} in propylene carbonate, and electrochromism was documented by spectrophotometry. The charge density exchange, and hence the optical modulation span, decayed gradually upon repeated cycling. This phenomenon was accurately described by an empirical power law, which was valid for at least 10{sup 4} cycles when the applied voltage was limited to 4.1?V vs Li/Li{sup +}. Our results allow lifetime assessments for one of the essential components in an electrochromic device such as a “smart window” for energy-efficient buildings.

  6. Near-Millimeter Wave Issues for a Space Power Grid Narayanan Komerath, Vigneshwar Venkat, Jason Fernandez

    E-Print Network [OSTI]

    for the power generated when the sun is brightest or the wind is strongest. Real-time beaming also allows collectors and converters to generate beamed microwaves from concentrated solar power, feeding into the established space power grid at lower costs. In Phase 3, large areas of ultra light collectors in high orbits

  7. Decay estimates for the one-dimensional wave equation with an inverse power potential

    E-Print Network [OSTI]

    Roland Donninger; Wilhelm Schlag

    2010-03-10

    We study the wave equation on the real line with a potential that falls off like $|x|^{-\\alpha}$ for $|x| \\to \\infty$ where $2 < \\alpha \\leq 4$. We prove that the solution decays pointwise like $t^{-\\alpha}$ as $t \\to \\infty$ provided that there are no resonances at zero energy and no bound states. As an application we consider the $\\ell=0$ Price Law for Schwarzschild black holes. This paper is part of our investigations into decay of linear waves on a Schwarzschild background.

  8. CONTROL OF POPULATION DENSITIES SURROUNDING NUCLEAR POWER PLANTS. VOLUME 5 OF THE FINAL REPORT ON HEALTH AND SAFETY IMPACTS OF NUCLEAR, GEOTHERMAL, AND FOSSIL-FUEL ELECTRIC GENERATION IN CALIFORNIA

    E-Print Network [OSTI]

    Nero, jA.V.

    2010-01-01

    Related Standards for Nuclear Power Plants," by A.V. NeroResponse Planning for Nuclear Power Plants in California,"Densities Surrounding Nuclear Power Plants," by A.V. Nero,

  9. Charge Density Waves in Exfoliated Films of van der Waals Materials: Evolution of Raman Spectrum in TiSe2

    E-Print Network [OSTI]

    and slide through the crystal producing a collective current. CDW materials have been considered physical state variables for information process- ing.6 It has become clear that power dissipation of independent particles. If instead, the N electrons are in a collective state, then the minimum dissipation

  10. Exact Near-Onset Analysis of the Spin-Density-Wave Instability in Ferromagnetic Superconductors - the Linearly Polarized State 

    E-Print Network [OSTI]

    Hu, Chia-Ren.

    1984-01-01

    inteaction in real magnetic supercon- ductor s. ACKNOW LEDGMENTS This work was supported by National Science Founda- tion Grant No. DMR82-05697. It was partially worked out while the author was visiting the Argonne National Laboratory (ANL...). The dislocation support from ANL and the warm hospitality of Dr. G. W. Crabtree are grate- fully acknowledged. 30 EXACT NEAR-ONSET ANALYSIS OF THE SPIN-DENSITY-. . . 2589 ~E. I. Blount and C. M. Valma, Phys. Rev. Lett. 42, 1079 (1979). ~D. E. Moncton, D. B...

  11. Exact, E=0, Solutions for General Power-Law Potentials. II. Quantum Wave Functions

    E-Print Network [OSTI]

    Jamil Daboul; Michael Martin Nieto

    1994-08-09

    For zero energy, $E=0$, we derive exact, quantum solutions for {\\it all} power-law potentials, $V(r) = -\\gamma/r^{\

  12. A High Power Density Electrostatic Vibration-to-Electric Energy Converter Based On An In-Plane Overlap Plate (IPOP) Mechanism

    E-Print Network [OSTI]

    Paracha, A M; Marty, F; Chasin, A Vaisman; Poulichet, P; Bourouina, T

    2008-01-01

    In this paper, design, fabrication and characterization issues of a bulk silicon-based, vibration powered, electric energy generator are addressed. The converter is based on an In-Plane Overlap Plate (IPOP) configuration [1]. Measurements have shown that with a theoretically lossless electronics and a starting voltage of 5 V, power density of 58 $\\mu$W/cm3 is achievable at the resonance frequency of 290 Hz. It can be further improved by reducing the parasitic capacitance, which can be achieved by silicon etching, but a considerable mass is lost. In [2], it is shown that 19% of mass reduction improves power density from 12.95 $\\mu$W/cm3 to 59 $\\mu$W/cm3. Hence an enhancement in fabrication process is proposed, which is termed as Backside DRIE. It helps in increasing power density without loosing an important quantity of mass. Simulations have shown that 2.5% of mass removal improves power density up to 76.71 $\\mu$W/cm3. Initial simulation results and problems of associated electronics are also discussed.

  13. Environmental assessment for the Satellite Power System (SPS): studies of honey bees exposed to 2. 45 GHz continuous-wave electromagnetic energy

    SciTech Connect (OSTI)

    Gary, N E; Westerdahl, B B

    1980-12-01

    A system for small animal exposure was developed for treating honey bees, Apis mellifera L., in brood and adult stages, with 2.45 GHz continuous wave microwaves at selected power densities and exposure times. Post-treatment brood development was normal and teratological effects were not detected at exposures of 3 to 50 mw/cm/sup 2/ for 30 minutes. Post-treatment survival, longevity, orientation, navigation, and memory of adult bees were also normal after exposures of 3 to 50 mw/cm/sup 2/ for 30 minutes. Post-treatment longevity of confined bees in the laboratory was normal after exposures of 3 to 50 mw/cm/sup 2/ for 24 hours. Thermoregulation of brood nest, foraging activity, brood rearing, and social interaction were not affected by chronic exposure to 1 mw/cm/sup 2/ during 28 days. In dynamic behavioral bioassays the frequency of entry and duration of activity of unrestrained, foraging adult bees was identical in microwave-exposed (5 to 40 mw/cm/sup 2/) areas versus control areas.

  14. Observation of low magnetic field density peaks in helicon plasma

    SciTech Connect (OSTI)

    Barada, Kshitish K.; Chattopadhyay, P. K.; Ghosh, J.; Kumar, Sunil; Saxena, Y. C. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)

    2013-04-15

    Single density peak has been commonly observed in low magnetic field (<100 G) helicon discharges. In this paper, we report the observations of multiple density peaks in low magnetic field (<100 G) helicon discharges produced in the linear helicon plasma device [Barada et al., Rev. Sci. Instrum. 83, 063501 (2012)]. Experiments are carried out using argon gas with m = +1 right helical antenna operating at 13.56 MHz by varying the magnetic field from 0 G to 100 G. The plasma density varies with varying the magnetic field at constant input power and gas pressure and reaches to its peak value at a magnetic field value of {approx}25 G. Another peak of smaller magnitude in density has been observed near 50 G. Measurement of amplitude and phase of the axial component of the wave using magnetic probes for two magnetic field values corresponding to the observed density peaks indicated the existence of radial modes. Measured parallel wave number together with the estimated perpendicular wave number suggests oblique mode propagation of helicon waves along the resonance cone boundary for these magnetic field values. Further, the observations of larger floating potential fluctuations measured with Langmuir probes at those magnetic field values indicate that near resonance cone boundary; these electrostatic fluctuations take energy from helicon wave and dump power to the plasma causing density peaks.

  15. High-power, mid-infrared, picosecond pulses generated by compression of a CO2 laser beat-wave in GaAs

    E-Print Network [OSTI]

    Pigeon, J J; Joshi, C

    2015-01-01

    We report on the generation of a train of ~ 2 ps, 10 um laser pulses via multiple four-wave mixing and compression of an infrared laser beat-wave propagating in the negative group velocity dispersion region of bulk GaAs and a combination of GaAs and NaCl. The use of a 200 ps, 106 GHz beat-wave, produced by combining laser pulses amplified on the 10P(20) and 10P(16) transition of a CO2 laser, provides a novel method for generating high-power, picosecond, mid-IR laser pulses at a high repetition rate. By using 165 and 882 GHz beat-waves we show that cascaded phase-mismatched difference frequency generation plays a significant role in the four-wave mixing process in GaAs.

  16. MHK Projects/Coos County Offshore Wave Energy Power Plant | Open Energy

    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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource HistoryScenarios Towards 2050 JumpCoos Bay OPT Wave Park < MHK Projects

  17. GEOPHYSICAL RESEARCH LETTERS, VOL. 26, NO. 16, PAGES 2629-2632, AUGUST 15, 1999 Modulated electron-acoustic waves in auroral density

    E-Print Network [OSTI]

    Carlson, Charles W.

    of the parallel auroral accelera- tion region. They form intense packets of electron acoustic waves. The modulation is due to ion acoustic waves. These structures are electrostatic and propagate along the mag exhibit signatures of electron acoustic wave activity. Elec- tron acoustic waves are known to contribute

  18. Interferometric adaptive optics for high power laser pointing, wave-front control and phasing

    SciTech Connect (OSTI)

    Baker, K L; Stappaerts, E A; Homoelle, D C; Henesian, M A; Bliss, E S; Siders, C W; Barty, C J

    2009-01-21

    Implementing the capability to perform fast ignition experiments, as well as, radiography experiments on the National Ignition Facility (NIF) places stringent requirements on the control of each of the beam's pointing and overall wavefront quality. One quad of the NIF beams, 4 beam pairs, will be utilized for these experiments and hydrodynamic and particle-in-cell simulations indicate that for the fast ignition experiments, these beams will be required to deliver 50% (4.0 kJ) of their total energy (7.96 kJ) within a 40 {micro}m diameter spot at the end of a fast ignition cone target. This requirement implies a stringent pointing and overall phase conjugation error budget on the adaptive optics system used to correct these beam lines. The overall encircled energy requirement is more readily met by phasing of the beams in pairs but still requires high Strehl ratios, Sr, and rms tip/tilt errors of approximately one {micro}rad. To accomplish this task we have designed an interferometric adaptive optics system capable of beam pointing, high Strehl ratio and beam phasing with a single pixilated MEMS deformable mirror and interferometric wave-front sensor. We present the design of a testbed used to evaluate the performance of this wave-front sensor below along with simulations of its expected performance level.

  19. Higher Fock states and power counting in exclusive P-wave quarkonium decays

    E-Print Network [OSTI]

    Jan Bolz; Peter Kroll; Gerhard A. Schuler

    1997-04-22

    Exclusive processes at large momentum transfer Q factor into perturbatively calculable short-distance parts and long-distance hadronic wave functions. Usually, only contributions from the leading Fock states have to be included to leading order in 1/Q. We show that for exclusive decays of P-wave quarkonia the contribution from the next-higher Fock state |Q Qbar g> contributes at the same order in 1/Q. We investigate how the constituent gluon attaches to the hard process in order to form colour-singlet final-state hadrons and argue that a single additional long-distance factor is sufficient to parametrize the size of its contribution. Incorporating transverse degrees of freedom and Sudakov factors, our results are perturbatively stable in the sense that soft phase-space contributions are largely suppressed. Explicit calculations yield good agreement with data on chi_{c J} decays into pairs of pions, kaons, and etas. We also comment on J/psi decays into two pions.

  20. Experimental observation of standing wave effect in low-pressure very-high-frequency capacitive discharges

    SciTech Connect (OSTI)

    Liu, Yong-Xin; Gao, Fei; Liu, Jia; Wang, You-Nian

    2014-07-28

    Radial uniformity measurements of plasma density were carried out by using a floating double probe in a cylindrical (21?cm in electrode diameter) capacitive discharge reactor driven over a wide range of frequencies (27–220 MHz). At low rf power, a multiple-node structure of standing wave effect was observed at 130?MHz. The secondary density peak caused by the standing wave effect became pronounced and shifts toward the axis as the driving frequency further to increase, indicative of a much more shortened standing-wave wavelength. With increasing rf power, the secondary density peak shift toward the radial edge, namely, the standing-wave wavelength was increased, in good qualitative agreement with the previous theory and simulation results. At higher pressures and high frequencies, the rf power was primarily deposited at the periphery of the electrode, due to the fact that the waves were strongly damped as they propagated from the discharge edge into the center.

  1. Probing the plasma near high power wave launchers in fusion devices for static and dynamic electric fields (invited)

    SciTech Connect (OSTI)

    Klepper, C. C., E-mail: kleppercc@ornl.gov; Isler, R. C.; Biewer, T. M.; Caughman, J. B.; Green, D. L.; Harris, J. H.; Hillis, D. L. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States); Martin, E. H. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6169 (United States); North Carolina State University, Raleigh, North Carolina 27607 (United States); Colas, L.; Goniche, M.; Hillairet, J.; Panayotis, S.; Pegourié, B.; Jacquot, J.; Lotte, Ph.; Colledani, G.; Ekedahl, A.; Litaudon, X. [CEA, IRFM, F-13108 Saint Paul-lez-Durance (France); Shannon, S. C. [North Carolina State University, Raleigh, North Carolina 27607 (United States)

    2014-11-15

    An exploratory study was carried out in the long-pulse tokamak Tore Supra, to determine if electric fields in the plasma around high-power, RF wave launchers could be measured with non-intrusive, passive, optical emission spectroscopy. The focus was in particular on the use of the external electric field Stark effect. The feasibility was found to be strongly dependent on the spatial extent of the electric fields and overlap between regions of strong (>?1 kV/cm) electric fields and regions of plasma particle recycling and plasma-induced, spectral line emission. Most amenable to the measurement was the RF electric field in edge plasma, in front of a lower hybrid heating and current drive launcher. Electric field strengths and direction, derived from fitting the acquired spectra to a model including time-dependent Stark effect and the tokamak-range magnetic field Zeeman-effect, were found to be in good agreement with full-wave modeling of the observed launcher.

  2. Probing the plasma near high power wave launchers in fusion devices for static and dynamic electric fields

    SciTech Connect (OSTI)

    Klepper, C Christopher; Martin, Elijah H; Isler, Ralph C; Colas, L.; Goniche, M.; Hillairet, J.; Panayotis, Stephanie; Jacquot, Jonathan; Lotte, Ph.; Colledani, G.; Biewer, Theodore M; Caughman, J. B. O.; Ekedahl, A.; Green, David L; Harris, Jeffrey H; Hillis, Donald Lee; Shannon, Prof. Steven; Litaudon, X

    2014-01-01

    An exploratory study was carried out in the long-pulse tokamak Tore Supra, to determine if electric fields in the plasma around high-power, RF wave launchers could be measured with non-intrusive, passive, optical emission spectroscopy. The focus was in particular on the use of the external electric field Stark effect. The feasibility was found to be strongly dependent on the spatial extent of the electric fields and overlap between regions of strong (> 1 kV/cm) electric fields and regions of plasma particle recycling and plasma-induced, spectral line emission. Most amenable to the measurement was the RF electric field in edge plasma, in front of a lower hybrid heating and current drive launcher. Electric field strengths and direction, derived from fitting the acquired spectra to a model including time-dependent Stark effect and the tokamak-range magnetic field Zeeman-effect, were found to be in good agreement with full-wave modeling of the observed launcher.

  3. Surface-emitting terahertz quantum cascade lasers with continuous-wave power in the tens of milliwatt range

    SciTech Connect (OSTI)

    Xu, Gangyi, E-mail: gangyi.xu@mail.sitp.ac.cn [Institut d'Electronique Fondamentale, Univ. Paris Sud, UMR8622 CNRS, 91405 Orsay (France); Key Laboratory of Infrared Imaging Materials and Detectors, Shanghai Institute of Technical Physics, Chinese Academy of Sciences, Shanghai 200083 (China); Li, Lianhe; Giles Davies, A.; Linfield, Edmund H. [School of Electronic and Electrical Engineering, University of Leeds, Leeds LS9 2JT (United Kingdom); Isac, Nathalie; Halioua, Yacine; Colombelli, Raffaele, E-mail: raffaele.colombelli@u-psud.fr [Institut d'Electronique Fondamentale, Univ. Paris Sud, UMR8622 CNRS, 91405 Orsay (France)

    2014-03-03

    We demonstrate efficient surface-emitting terahertz frequency quantum cascade lasers with continuous wave output powers of 20–25?mW at 15?K and maximum operating temperatures of 80–85?K. The devices employ a resonant-phonon depopulation active region design with injector, and surface emission is realized using resonators based on graded photonic heterostructures (GPHs). GPHs can be regarded as energy wells for photons and have recently been implemented through grading the period of the photonic structure. In this paper, we show that it is possible to keep the period constant and grade instead the lateral metal coverage across the GPH. This strategy ensures spectrally single-mode operation across the whole laser dynamic range and represents an additional degree of freedom in the design of confining potentials for photons.

  4. In Situ Evaluation of Density, Viscosity and Thickness of Adsorbed Soft Layers by Combined Surface Acoustic Wave and Surface Plasmon Resonance

    E-Print Network [OSTI]

    L. Francis; J. -M. Friedt; C. Zhou; P. Bertrand

    2006-04-28

    We show the theoretical and experimental combination of acoustic and optical methods for the in situ quantitative evaluation of the density, the viscosity and the thickness of soft layers adsorbed on chemically tailored metal surfaces. For the highest sensitivity and an operation in liquids, a Love mode surface acoustic wave (SAW) sensor with a hydrophobized gold coated sensing area is the acoustic method, while surface plasmon resonance (SPR) on the same gold surface as the optical method is monitored simultaneously in a single set-up for the real-time and label-free measurement of the parameters of adsorbed soft layers, which means for layers with a predominant viscous behavior. A general mathematical modeling in equivalent viscoelastic transmission lines is presented to determine the correlation between experimental SAW signal shifts and the waveguide structure including the presence of the adsorbed layer and the supporting liquid from which it segregates. A methodology is presented to identify from SAW and SPR simulations the parameters representatives of the soft layer. During the absorption of a soft layer, thickness or viscosity changes are observed in the experimental ratio of the SAW signal attenuation to the SAW signal phase and are correlated with the theoretical model. As application example, the simulation method is applied to study the thermal behavior of physisorbed PNIPAAm, a polymer whose conformation is sensitive to temperature, under a cycling variation of temperature between 20 and 40 oC. Under the assumption of the bulk density and the bulk refractive index of PNIPAAm, thickness and viscosity of the film are obtained from simulations; the viscosity is correlated to the solvent content of the physisorbed layer.

  5. Sandia Energy - WEC-Sim (Wave Energy Converter SIMulator)

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

    WEC-Sim (Wave Energy Converter SIMulator) Home Stationary Power Energy Conversion Efficiency Water Power WEC-Sim (Wave Energy Converter SIMulator) WEC-Sim (Wave Energy Converter...

  6. Power combiner

    DOE Patents [OSTI]

    Arnold, Mobius; Ives, Robert Lawrence

    2006-09-05

    A power combiner for the combining of symmetric and asymmetric traveling wave energy comprises a feed waveguide having an input port and a launching port, a reflector for reflecting launched wave energy, and a final waveguide for the collection and transport of launched wave energy. The power combiner has a launching port for symmetrical waves which comprises a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which comprises a sawtooth rotated about a central axis.

  7. Optical fiber evanescent wave adsorption sensors for high-temperature gas sensing in advanced coal-fired power plants

    SciTech Connect (OSTI)

    Buric, M.; Ohodnicky, P.; Duy, J.

    2012-01-01

    Modern advanced energy systems such as coal-fired power plants, gasifiers, or similar infrastructure present some of the most challenging harsh environments for sensors. The power industry would benefit from new, ultra-high temperature devices capable of surviving in hot and corrosive environments for embedded sensing at the highest value locations. For these applications, we are currently exploring optical fiber evanescent wave absorption spectroscopy (EWAS) based sensors consisting of high temperature core materials integrated with novel high temperature gas sensitive cladding materials. Mathematical simulations can be used to assist in sensor development efforts, and we describe a simulation code that assumes a single thick cladding layer with gas sensitive optical constants. Recent work has demonstrated that Au nanoparticle-incorporated metal oxides show a potentially useful response for high temperature optical gas sensing applications through the sensitivity of the localized surface plasmon resonance absorption peak to ambient atmospheric conditions. Hence, the simulation code has been applied to understand how such a response can be exploited in an optical fiber based EWAS sensor configuration. We demonstrate that interrogation can be used to optimize the sensing response in such materials.

  8. Train of high-power femtosecond pulses: Probe wave in a gas of prepared atoms

    E-Print Network [OSTI]

    Gevorg Muradyan; A. Zh. Muradyan

    2009-08-21

    We present a new method for generating a regular train of ultrashort optical pulses in a prepared two-level medium. The train develops from incident monochromatic probe radiation travelling in a medium of atoms, which are in a quantum mechanical superposition of dressed internal states. In the frame of used linear theory for the probe radiation, the energy of individual pulses is an exponentially growing function of atom density and of interaction cross section. Pulse repetition rate is determined by the generalized Rabi frequency and can be around 1 THz and greater. We also show that the terms, extra to the dipole approximation, endow the gas by a new property: non-saturating dependence of refractive index on the dressing monochromatic field intensity. Contribution of these nonsaturating terms can be compatible with the main dipole approximation in the wavelength region of about ten micrometers (the range of CO_2 laser) or larger.

  9. Internal Wave Interferometry

    E-Print Network [OSTI]

    Mathur, Manikandan S.

    Internal waves are a ubiquitous and significant means of momentum and energy transport in the oceans, atmosphere, and astrophysical bodies. Here, we show that internal wave propagation in nonuniform density stratifications, ...

  10. Modified Szabo's wave equation models for lossy media obeying frequency power law

    E-Print Network [OSTI]

    W. Chen; S. Holm

    2002-12-30

    Szabo's models of acoustic attenuation (Szabo 1994a) comply well with the empirical frequency power law involving non-integer and odd integer exponent coefficients while guaranteering causality, but nevertheless encounter the troublesome issues of hyper-singular improper integral and obscurity in implementing initial conditions. The purpose of this paper is to ease or remove these drawbacks of the Szabo's models via the Caputo fractional derivative concept. The positive time fractional derivative is also first introduced to include the positivity of the attenuation possesses.

  11. Riding the Clean Energy Wave: New Projects Aim to Improve Water Power

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMassR&D100Nationalquestionnaires 0serialIndustrialSenior8Rick StevensA Megawatt

  12. Performance Assessment of the Wave Dragon Wave Energy Converter

    E-Print Network [OSTI]

    Hansen, René Rydhof

    Performance Assessment of the Wave Dragon Wave Energy Converter Based on the EquiMar Methodology S of the wave energy sector, device developers are called to provide reliable estimates on power performanceMar, Nissum Bredning, Hanstholm, North Sea, Ekofisk, Wave-to-wire, Wave energy. I. INTRODUCTION The wave

  13. Kinetic Alfvén wave turbulence and formation of localized structures

    SciTech Connect (OSTI)

    Sharma, R. P.; Modi, K. V.; Mechanical Engineering Department, Government Engineering College Valsad, Gujarat 396001

    2013-08-15

    This work presents non-linear interaction of magnetosonic wave with kinetic Alfvén wave for intermediate ?-plasma (m{sub e}/m{sub i}???1). A set of dimensionless equations have been developed for analysis by considering ponderomotive force due to pump kinetic Alfvén wave in the dynamics of magnetosonic wave. Stability analysis has been done to study modulational instability or linear growth rate. Further, numerical simulation has been carried out to study the nonlinear stage of instability and resulting power spectrum applicable to solar wind around 1 AU. Due to the nonlinearity, background density of magnetosonic wave gets modified which results in localization of kinetic Alfvén wave. From the obtained results, we observed that spectral index follows k{sup ?3.0}, consistent with observation received by Cluster spacecraft for the solar wind around 1 AU. The result shows the steepening of power spectrum which may be responsible for heating and acceleration of plasma particles in solar wind.

  14. High-Temperature SiC Power Module with Integrated SiC Gate Drivers for Future High-Density Power Electronics Applications

    SciTech Connect (OSTI)

    Whitaker, Mr. Bret [APEI, Inc.; Cole, Mr. Zach [APEI, Inc.; Passmore, Mr. Brandon [APEI, Inc.; Mcnutt, Tyler [APEI, Inc.; Lostetter, Dr. Alex [APEI, Inc.; Ericson, Milton Nance [ORNL; Frank, Steven [ORNL; Britton Jr, Charles L [ORNL; Marlino, Laura D [ORNL; Mantooth, Alan [University of Arkansas; Francis, Matt [APEI, Inc.; Lamichhane, Ranjan [APEI, Inc.; Shepherd, Paul [APEI, Inc.; Glover, Michael [APEI, Inc.

    2014-01-01

    This paper presents a high-temperature capable intelligent power module that contains SiC power devices and SiC gate driver integrated circuits (ICs). The high-temperature capability of the SiC gate driver ICs allows for them to be packaged into the power module and be located physically close to the power devices. This provides a distinct advantage by reducing the gate driver loop inductance, which promotes high frequency operation, while also reducing the overall volume of the system through higher levels of integration. The power module was tested in a bridgeless-boost converter (Fig. 1) to determine the performance of the module in a system level application. The converter was operated with a switching frequency of 200 kHz with a peak output power of approximately 5 kW. The peak efficiency was found to be 97.5% at 2.9 kW.

  15. Symmetry-Breaking Orbital Anisotropy Observed for Detwinned Ba(Fe1-xCox)2As2 above the Spin Density Wave Transition

    SciTech Connect (OSTI)

    Yi, Ming

    2011-08-19

    Nematicity, defined as broken rotational symmetry, has recently been observed in competing phases proximate to the superconducting phase in the cuprate high temperature superconductors. Similarly, the new iron-based high temperature superconductors exhibit a tetragonal to orthorhombic structural transition (i.e. a broken C{sub 4} symmetry) that either precedes or is coincident with a collinear spin density wave (SDW) transition in undoped parent compounds, and superconductivity arises when both transitions are suppressed via doping. Evidence for strong in-plane anisotropy in the SDW state in this family of compounds has been reported by neutron scattering, scanning tunneling microscopy, and transport measurements. Here we present an angle resolved photoemission spectroscopy study of detwinned single crystals of a representative family of electron-doped iron-arsenide superconductors, Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} in the underdoped region. The crystals were detwinned via application of in-plane uniaxial stress, enabling measurements of single domain electronic structure in the orthorhombic state. At low temperatures, our results clearly demonstrate an in-plane electronic anisotropy characterized by a large energy splitting of two orthogonal bands with dominant d{sub xz} and d{sub yz} character, which is consistent with anisotropy observed by other probes. For compositions x > 0, for which the structural transition (T{sub S}) precedes the magnetic transition (T{sub SDW}), an anisotropic splitting is observed to develop above T{sub SDW}, indicating that it is specifically associated with T{sub S}. For unstressed crystals, the band splitting is observed close to T{sub S}, whereas for stressed crystals the splitting is observed to considerably higher temperatures, revealing the presence of a surprisingly large in-plane nematic susceptibility in the electronic structure.

  16. Compact, Low-Profile Power Converters: Highly-Laminated, High-Saturation-Flux-Density, Magnetic Cores for On-Chip Inductors in Power Converter Applications

    SciTech Connect (OSTI)

    None

    2010-09-01

    ADEPT Project: Georgia Tech is creating compact, low-profile power adapters and power bricks using materials and tools adapted from other industries and from grid-scale power applications. Adapters and bricks convert electrical energy into useable power for many types of electronic devices, including laptop computers and mobile phones. These converters are often called wall warts because they are big, bulky, and sometimes cover up an adjacent wall socket that could be used to power another electronic device. The magnetic components traditionally used to make adapters and bricks have reached their limits; they can't be made any smaller without sacrificing performance. Georgia Tech is taking a cue from grid-scale power converters that use iron alloys as magnetic cores. These low-cost alloys can handle more power than other materials, but the iron must be stacked in insulated plates to maximize energy efficiency. In order to create compact, low-profile power adapters and bricks, these stacked iron plates must be extremely thin-only hundreds of nanometers in thickness, in fact. To make plates this thin, Georgia Tech is using manufacturing tools used in microelectromechanics and other small-scale industries.

  17. Relic gravitational waves in the frame of slow-roll inflation with a power-law potential and the detection

    E-Print Network [OSTI]

    Ming-Lei Tong

    2013-02-22

    We obtained the analytic solutions of relic gravitational waves (RGWs) for the slow-roll inflation with a power-law form potential of the scalar field, $V=\\lambda\\phi^n$. Based on a reasonable range of $n$ constrained by cosmic microwave background (CMB) observations, we give tight constraints of the tensor-to-scalar ratio $r$ and the inflation expansion index $\\beta$ for the fixed scalar spectral index $n_s$. Even though, the spectrum of RGWs in low frequencies is hardly depends on any parameters, the high frequency parts will be affected by several parameters, such as $n_s$, the reheating temperature $T_{RH}$ and the index $\\beta_s$ describing the expansion from the end of inflation to the reheating process. We analyzed in detail all the factors which would affect the spectrum of RGWs in high frequencies including the quantum normalization. We found that the future GW detectors SKA, eLISA, BBO and DECIGO are promising to catch the signals of RGWs. Furthermore, BBO and DECIGO have the potential not only to distinguish the spectra with different parameters but also to examine the validity of the quantum normalization.

  18. On expansion of equal-time relativistic two-body wave equations in powers of 1/c to higher orders

    E-Print Network [OSTI]

    Alexei Turovsky

    2012-11-29

    Based on an extension of the Foldy--Wouthuysen method to two-body equations, the problem of expansion of equal-time relativistic equations for two Dirac particles in powers of $1/c$ to higher orders is considered. For the case of two particles with unequal masses, the transformed Hamiltonian in a general even-even form is obtained to order $1/c^4$. It is found that certain extra terms, which can be eliminated by an additional unitary transformation, arise in the expansion in higher orders, depending on the order of application of the generating functions in the first iteration. As examples for illustration, the Breit equation and the Salpeter equation with the Breit interaction are taken and their reduction to approximate forms including all the $1/c^{4}$-order terms is carried out using the method under consideration. The obtained results may be applied for the nonrelativistic expansion of two-body wave equations with various interaction potentials to higher orders, for the investigation of their features and symmetries, and may also be useful in the study of light atoms.

  19. Designing materials for energy storage with high power and energy density : LiFePO? cathode material

    E-Print Network [OSTI]

    Kang, Byoungwoo

    2010-01-01

    LiFePO? has drawn a lot of attention as a cathode material in lithium rechargeable batteries because its structural and thermal stability, its inexpensive cost, and environmental friendliness meet the requirements of power ...

  20. Low power low-density parity-checking (ldpc) codes decoder design using dynamic voltage and frequency scaling 

    E-Print Network [OSTI]

    Wang, Weihuang

    2009-05-15

    This thesis presents a low-power LDPC decoder design based on speculative scheduling of energy necessary to decode dynamically varying data frame in both block-fading channels and general AWGN channels. A model of a ...

  1. System using a megawatt class millimeter wave source and a high-power rectenna to beam power to a suspended platform

    DOE Patents [OSTI]

    Caplan, Malcolm; Friedman, Herbert W.

    2005-07-19

    A system for beaming power to a high altitude platform is based upon a high power millimeter gyrotron source, optical transmission components, and a high-power receiving antenna (i.e., a rectenna) capable of rectifying received millimeter energy and converting such energy into useable electrical power.

  2. Mapping and Assessment of the United States Ocean Wave Energy Resource

    SciTech Connect (OSTI)

    Paul T. Jacobson; George Hagerman; George Scott

    2011-12-01

    This project estimates the naturally available and technically recoverable U.S. wave energy resources, using a 51-month Wavewatch III hindcast database developed especially for this study by National Oceanographic and Atmospheric Administration�¢����s (NOAA�¢����s) National Centers for Environmental Prediction. For total resource estimation, wave power density in terms of kilowatts per meter is aggregated across a unit diameter circle. This approach is fully consistent with accepted global practice and includes the resource made available by the lateral transfer of wave energy along wave crests, which enables wave diffraction to substantially reestablish wave power densities within a few kilometers of a linear array, even for fixed terminator devices. The total available wave energy resource along the U.S. continental shelf edge, based on accumulating unit circle wave power densities, is estimated to be 2,640 TWh/yr, broken down as follows: 590 TWh/yr for the West Coast, 240 TWh/yr for the East Coast, 80 TWh/yr for the Gulf of Mexico, 1570 TWh/yr for Alaska, 130 TWh/yr for Hawaii, and 30 TWh/yr for Puerto Rico. The total recoverable wave energy resource, as constrained by an array capacity packing density of 15 megawatts per kilometer of coastline, with a 100-fold operating range between threshold and maximum operating conditions in terms of input wave power density available to such arrays, yields a total recoverable resource along the U.S. continental shelf edge of 1,170 TWh/yr, broken down as follows: 250 TWh/yr for the West Coast, 160 TWh/yr for the East Coast, 60 TWh/yr for the Gulf of Mexico, 620 TWh/yr for Alaska, 80 TWh/yr for Hawaii, and 20 TWh/yr for Puerto Rico.

  3. A thermally self-sustained micro solid-oxide fuel-cell stack with high power density

    E-Print Network [OSTI]

    Haile, Sossina M.

    output and rapid start-up by using single chamber operation on propane fuel. The catalytic oxidation in the absence of external heating. Of the fuel choices available for portable power applications, propane is par of Technology, Pasadena, California 91125, USA. 2 Department of Aerospace and Mechanical Engineering, University

  4. Numerical simulations of acoustically generated gravitational waves at a first order phase transition

    E-Print Network [OSTI]

    Mark Hindmarsh; Stephan J. Huber; Kari Rummukainen; David J. Weir

    2015-04-13

    We present details of numerical simulations of the gravitational radiation produced by a first order {thermal} phase transition in the early universe. We confirm that the dominant source of gravitational waves is sound waves generated by the expanding bubbles of the low-temperature phase. We demonstrate that the sound waves have a power spectrum with power-law form between the scales set by the average bubble separation (which sets the length scale of the fluid flow $L_\\text{f}$) and the bubble wall width. The sound waves generate gravitational waves whose power spectrum also has a power-law form, at a rate proportional to $L_\\text{f}$ and the square of the fluid kinetic energy density. We identify a dimensionless parameter $\\tilde\\Omega_\\text{GW}$ characterising the efficiency of this "acoustic" gravitational wave production whose value is $8\\pi\\tilde\\Omega_\\text{GW} \\simeq 0.8 \\pm 0.1$ across all our simulations. We compare the acoustic gravitational waves with the standard prediction from the envelope approximation. Not only is the power spectrum steeper (apart from an initial transient) but the gravitational wave energy density is generically two orders of magnitude or more larger.

  5. EARLY AFTERGLOWS OF GAMMA-RAY BURSTS IN A STRATIFIED MEDIUM WITH A POWER-LAW DENSITY DISTRIBUTION

    SciTech Connect (OSTI)

    Yi, Shuang-Xi; Dai, Zi-Gao [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Wu, Xue-Feng, E-mail: dzg@nju.edu.cn [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008 (China)

    2013-10-20

    A long-duration gamma-ray burst (GRB) has been widely thought to arise from the collapse of a massive star, and it has been suggested that its ambient medium is a homogenous interstellar medium (ISM) or a stellar wind. There are two shocks when an ultra-relativistic fireball that has been ejected during the prompt gamma-ray emission phase sweeps up the circumburst medium: a reverse shock that propagates into the fireball, and a forward shock that propagates into the ambient medium. In this paper, we investigate the temporal evolution of the dynamics and emission of these two shocks in an environment with a general density distribution of n?R {sup –k} (where R is the radius) by considering thick-shell and thin-shell cases. A GRB afterglow with one smooth onset peak at early times is understood to result from such external shocks. Thus, we can determine the medium density distribution by fitting the onset peak appearing in the light curve of an early optical afterglow. We apply our model to 19 GRBs and find that their k values are in the range of 0.4-1.4, with a typical value of k ? 1, implying that this environment is neither a homogenous ISM with k = 0 nor a typical stellar wind with k = 2. This shows that the progenitors of these GRBs might have undergone a new mass-loss evolution.

  6. Critical Parameters for Turbulent Transport in the SOL: Mechanism for the L-H Transition and its impact on the H-mode Power Threshold and Density Limit in ITER

    E-Print Network [OSTI]

    Critical Parameters for Turbulent Transport in the SOL: Mechanism for the L-H Transition and its impact on the H-mode Power Threshold and Density Limit in ITER

  7. Aspects of wave turbulence in preheating

    SciTech Connect (OSTI)

    Crespo, José A.; De Oliveira, H.P., E-mail: jaacrespo@gmail.com, E-mail: oliveira@dft.if.uerj.br [Universidade do Estado do Rio de Janeiro, Instituto de Física - Departamento de Física Teórica, Rio de Janeiro, RJ, CEP 20550-013 Brazil. (Brazil)

    2014-06-01

    In this work we have studied the nonlinear preheating dynamics of several inflationary models. It is well established that after a linear stage of preheating characterized by the parametric resonance, the nonlinear dynamics becomes relevant driving the system towards turbulence. Wave turbulence is the appropriated description of this phase since the matter contents are fields instead of usual fluids. Turbulence develops due to the nonlinear interations of waves, here represented by the small inhomogeneities of the scalar fields. We present relevant aspects of wave turbulence such as the Kolmogorov-Zakharov spectrum in frequency and wave number that indicates the energy transfer through scales. From the power spectrum of the matter energy density we were able to estimate the temperature of the thermalized system.

  8. Improved efficiency and power density for thermoacoustic coolers. Technical report, 1 June 1995-31 May 1996

    SciTech Connect (OSTI)

    Hofler, T.J.

    1996-06-01

    Work continues on building a thermoacoustic heat driven cooler having no moving parts, with cooling power in the 0.5 to 1.0 kW range. Previous work dealt with numerical modeling of a new engine topology used in the above engine and various work on improved heat exchangers. Recently, morn modeling suggests that cooling powers in the range of 35 kW (10 ton) may be possible with an engine having a longest dimension of 4 ft. and that efficiency improves significantly with size. Also, the authors have solved some fabrication problems with their high temperature nickel heat exchangers. The major work this year has been on the high temperature thermoacoustic stack structure. A common Stirling engine regenerator structure consisting of stacked disks cut from stainless steel wire mesh was tested in an apparatus previously used for high amplitude heat exchanger measurements. Stacks are very easy to construct in this fashion and longitudinal thermal conduction is greatly reduced. Results show that amplitude performance is very good and within 10% of the usual spiral roll structures. More impressively, the efficiency of the mesh stack is as much as 30% higher than for spiral rolls stacks. The authors are also conducting measurements on pure carbon random structures that could be used at extremely high temperatures.

  9. A Novel Overtopping Wave Energy Device Concept Applied to California

    E-Print Network [OSTI]

    Imamura, John

    2009-01-01

    for overtopping wave energy devices are limited in theirhigh power output wave energy devices may be possible.design and modeling of wave energy devices. Nat- urally this

  10. Bragg grating rogue wave

    E-Print Network [OSTI]

    Degasperis, Antonio; Aceves, Alejandro B

    2015-01-01

    We derive the rogue wave solution of the classical massive Thirring model, that describes nonlinear optical pulse propagation in Bragg gratings. Combining electromagnetically induced transparency with Bragg scattering four-wave mixing, may lead to extreme waves at extremely low powers.

  11. Scattering of radio frequency waves by blobs in tokamak plasmas

    SciTech Connect (OSTI)

    Ram, Abhay K.; Hizanidis, Kyriakos; Kominis, Yannis

    2013-05-15

    The density fluctuations and blobs present in the edge region of magnetic fusion devices can scatter radio frequency (RF) waves through refraction, reflection, diffraction, and coupling to other plasma waves. This, in turn, affects the spectrum of the RF waves and the electromagnetic power that reaches the core of the plasma. The usual geometric optics analysis of RF scattering by density blobs accounts for only refractive effects. It is valid when the amplitude of the fluctuations is small, of the order of 10%, compared to the background density. In experiments, density fluctuations with much larger amplitudes are routinely observed, so that a more general treatment of the scattering process is needed. In this paper, a full-wave model for the scattering of RF waves by a blob is developed. The full-wave approach extends the range of validity well beyond that of geometric optics; however, it is theoretically and computationally much more challenging. The theoretical procedure, although similar to that followed for the Mie solution of Maxwell's equations, is generalized to plasmas in a magnetic field. Besides diffraction and reflection, the model includes coupling to a different plasma wave than the one imposed by the external antenna structure. In the model, it is assumed that the RF waves interact with a spherical blob. The plasma inside and around the blob is cold, homogeneous, and imbedded in a uniform magnetic field. After formulating the complete analytical theory, the effect of the blob on short wavelength electron cyclotron waves and longer wavelength lower hybrid waves is studied numerically.

  12. 3-103 The power that could be produced by a water wheel is to be determined. Properties The density of water is taken to be 1000 m3

    E-Print Network [OSTI]

    Bahrami, Majid

    3-52 3-103 The power that could be produced by a water wheel is to be determined. Properties The density of water is taken to be 1000 m3 /kg (Table A-3). Analysis The power production is determined from The mass flow rate through the wind mill is kg/s7.457 /kg)m4(0.8409 m/s)(10m)7( 3 2 11 S v VA m The power

  13. Phase locking of an S-band wide-gap klystron amplifier with high power injection driven by a relativistic backward wave oscillator

    SciTech Connect (OSTI)

    Bai Xianchen; Zhang Jiande; Yang Jianhua; Jin Zhenxing [College of Optoelectronic Science and Engineering, National University of Defense Technology, Changsha 410073 (China)

    2012-12-15

    Theoretical analyses and preliminary experiments on the phase-locking characteristics of an inductively loaded 2-cavity wide-gap klystron amplifier (WKA) with high power injection driven by a GW-class relativistic backward wave oscillator (RBWO) are presented. Electric power of the amplifier and oscillator is supplied by a single accelerator being capable of producing dual electron beams. The well phase-locking effect of the RBWO-WKA system requires the oscillator have good frequency reproducibility and stability from pulse to pulse. Thus, the main switch of the accelerator is externally triggered to stabilize the diode voltage and then the working frequency. In the experiment, frequency of the WKA is linearly locked by the RBWO. With a diode voltage of 530 kV and an input power of {approx}22 MW, an output power of {approx}230 MW with the power gain of {approx}10.2 dB is obtained from the WKA. As the main switch is triggered, the relative phase difference between the RBWO and the WKA is less than {+-}15 Degree-Sign in a single shot, and phase jitter of {+-}11 Degree-Sign is obtained within a series of shots with duration of about 40 ns.

  14. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30

    This program allowed further advancing the development of a novel type of wave energy converter, a Cycloidal Wave Energy Converter or CycWEC. A CycWEC consists of one or more hydrofoils rotating around a central shaft, and operates fully submerged beneath the water surface. It operates under feedback control sensing the incoming waves, and converts wave power to shaft power directly without any intermediate power take off system. Previous research consisting of numerical simulations and two dimensional small 1:300 scale wave flume experiments had indicated wave cancellation efficiencies beyond 95%. The present work was centered on construction and testing of a 1:10 scale model and conducting two testing campaigns in a three dimensional wave basin. These experiments allowed for the first time for direct measurement of electrical power generated as well as the interaction of the CycWEC in a three dimensional environment. The Atargis team successfully conducted two testing campaigns at the Texas A&M Offshore Technology Research Center and was able to demonstrate electricity generation. In addition, three dimensional wave diffraction results show the ability to achieve wave focusing, thus increasing the amount of wave power that can be extracted beyond what was expected from earlier two dimensional investigations. Numerical results showed wave cancellation efficiencies for irregular waves to be on par with results for regular waves over a wide range of wave lengths. Using the results from previous simulations and experiments a full scale prototype was designed and its performance in a North Atlantic wave climate of average 30kW/m of wave crest was estimated. A full scale WEC with a blade span of 150m will deliver a design power of 5MW at an estimated levelized cost of energy (LCOE) in the range of 10-17 US cents per kWh. Based on the new results achieved in the 1:10 scale experiments these estimates appear conservative and the likely performance at full scale will exceed this initial performance estimates. In advancing the Technology Readiness Level (TRL) of this type of wave energy converter from 3 to 4, we find the CycWEC to exceed our initial estimates in terms of hydrodynamic performance. Once fully developed and optimized, it has the potential to not just outperform all other WEC technologies, but to also deliver power at a lower LCOE than competing conventional renewables like wind and solar. Given the large wave power resource both domestically and internationally, this technology has the potential to lead to a large improvement in our ability to produce clean electricity at affordable cost.

  15. An innovative high-power constant-current pulsed-arc power-supply for a high-density pulsed-arc-plasma ion-source using a LaB{sub 6}-filament

    SciTech Connect (OSTI)

    Ueno, A.; Oguri, H.; Ikegami, K.; Namekawa, Y.; Ohkoshi, K.; Tokuchi, A.

    2010-02-15

    An innovative high-power constant-current (CC) pulsed-arc (PA) power-supply (PS) indispensable for a high-density PA plasma ion-source using a lanthanum hexaboride (LaB{sub 6}) filament was devised by combining a constant-voltage (CV) PA-PS, which is composed of an insulated gate bipolar transistor (IGBT) switch, a CV direct-current (dc) PS and a 270 mF capacitor with a CC-PA-PS, which is composed of an IGBT-switch, a CC-dc-PS and a 400 {mu}H inductor, through the inductor. The hybrid-CC-PA-PS succeeded in producing a flat arc-pulse with a peak power of 56 kW (400 Ax140 V) and a duty factor of more than 1.5%(600 {mu}sx25 Hz) for Japan Proton Accelerator Research Complex (J-PARC) H{sup -} ion-source stably. It also succeeded in shortening the 99% rising-time of the arc-pulse-current to about 20 {mu}s and tilting up or down the arc-pulse-current arbitrarily and almost linearly by changing the setting voltage of its CV-dc-PS.

  16. Microwave and millimeter-wave rectifying circuit arrays and ultra-wideband antennas for wireless power transmission and communications 

    E-Print Network [OSTI]

    Ren, Yu-Jiun

    2009-05-15

    In the future, space solar power transmission and wireless power transmission will play an important role in gathering clean and infinite energy from space. The rectenna, i.e., a rectifying circuit combined with an antenna, is one of the most...

  17. Analysis of four-wave mixing of high-power lasers for the detection of elastic photon-photon scattering

    E-Print Network [OSTI]

    J. Lundin; M. Marklund; E. Lundstrom; G. Brodin; J. Collier; R. Bingham; J. T. Mendonca; P. Norreys

    2006-10-10

    We derive expressions for the coupling coefficients for electromagnetic four-wave mixing in the non-linear quantum vacuum. An experimental setup for detection of elastic photon-photon scattering is suggested, where three incoming laser pulses collide and generate a fourth wave with a new frequency and direction of propagation. An expression for the number of scattered photons is derived and, using beam parameters for the Astra Gemini system at the Rutherford Appleton Laboratory, it is found that the signal can reach detectable levels. Problems with shot-to-shot reproducibility are reviewed, and the magnitude of the noise arising from competing scattering processes is estimated. It is found that detection of elastic photon-photon scattering may for the first time be achieved.

  18. Measurements and Linear Wave Theory Based Simulations of Vegetated Wave Hydrodynamics for Practical Applications 

    E-Print Network [OSTI]

    Anderson, Mary Elizabeth

    2011-10-21

    impeded. Sparse vegetation fields dissipated less wave energy than the intermediate density; however, the extremely dense fields dissipated very little, if any, wave energy and sometimes wave growth was observed. This is possibly due to the highest...

  19. Constraining the gravitational wave energy density of the Universe in the Range 0.1 Hz to 1 Hz using the Apollo Seismic Array

    E-Print Network [OSTI]

    Michael Coughlin; Jan Harms

    2014-10-11

    In this paper, we describe an analysis of Apollo era lunar seismic data that places an upper limit on an isotropic stochastic gravitational-wave background integrated over a year in the frequency range 0.1\\,Hz -- 1\\,Hz. We find that because the Moon's ambient noise background is much quieter than that of the Earth, significant improvements over an Earth based analysis were made. We find an upper limit of $\\Omega_{\\rm GW}<1.2\\times 10^{5}$, which is three orders of magnitude smaller than a similar analysis of a global network of broadband seismometers on Earth and the best limits in this band to date. We also discuss the benefits of a potential Earth-Moon correlation search and compute the time-dependent overlap reduction function required for such an analysis. For this search, we find an upper limit an order of magnitude larger than the Moon-Moon search.

  20. Constraining the gravitational wave energy density of the Universe in the Range 0.1 Hz to 1 Hz using the Apollo Seismic Array

    E-Print Network [OSTI]

    Coughlin, Michael

    2014-01-01

    In this paper, we describe an analysis of Apollo era lunar seismic data that places an upper limit on an isotropic stochastic gravitational-wave background integrated over a year in the frequency range 0.1\\,Hz -- 1\\,Hz. We find that because the Moon's ambient noise background is much quieter than that of the Earth, significant improvements over an Earth based analysis were made. We find an upper limit of $\\Omega_{\\rm GW}<1.2\\times 10^{5}$, which is three orders of magnitude smaller than a similar analysis of a global network of broadband seismometers on Earth and the best limits in this band to date. We also discuss the benefits of a potential Earth-Moon correlation search and compute the time-dependent overlap reduction function required for such an analysis. For this search, we find an upper limit an order of magnitude larger than the Moon-Moon search.

  1. Nonlinear Electron Heat Conduction Equation and Self similar method for 1-D Thermal Waves in Laser Heating of Solid Density DT Fuel

    E-Print Network [OSTI]

    A. Mohammadian Pourtalari; M. A. Jafarizadeh; M. Ghoranneviss

    2011-11-23

    Electron heat conduction is one of the ways that energy transports in laser heating of fusible target material. The aim of Inertial Confinement Fusion (ICF) is to show that the thermal conductivity is strongly dependent on temperature and the equation of electron heat conduction is a nonlinear equation. In this article, we solve the one-dimensional (1-D) nonlinear electron heat conduction equation with a self-similar method (SSM). This solution has been used to investigate the propagation of 1-D thermal wave from a deuterium-tritium (DT) plane source which occurs when a giant laser pulse impinges onto a DT solid target. It corresponds to the physical problem of rapid heating of a boundary layer of material in which the energy of laser pulse is released in a finite initial thickness.

  2. Wave Propagation Theory 2.1 The Wave Equation

    E-Print Network [OSTI]

    2 Wave Propagation Theory 2.1 The Wave Equation The wave equation in an ideal fluid can be derived from hydrodynamics and the adia- batic relation between pressure and density. The equation for conservation of mass, Euler's equation (Newton's 2nd Law), and the adiabatic equation of state are respec

  3. Chiral Heat Wave and wave mixing in chiral media

    E-Print Network [OSTI]

    Chernodub, M N

    2015-01-01

    We show that a hot rotating fluid of relativistic chiral fermions possesses a new gapless collective excitation associated with coherent propagation of energy density and chiral density waves along the axis of rotation. This excitation, which we call the Chiral Heat Wave, emerges due to a mixed gauge-gravitational anomaly. At finite density the Chiral Heat Wave couples to the Chiral Vortical Wave while in the presence of an external magnetic field it mixes with the Chiral Magnetic Wave. We find that the coupled waves - which are coherent fluctuations of the vector, axial and energy currents - have generally different velocities compared to the velocities of the individual waves. We also demonstrate that rotating chiral systems subjected to external magnetic field possess non-propagating metastable thermal excitations, the Dense Hot Spots.

  4. One-dimensional full wave simulation on XB mode conversion in electron cyclotron heating

    SciTech Connect (OSTI)

    Kim, S. H., E-mail: shkim95@kaeri.re.kr [Korea Atomic Energy Research Institute, Daejeon 305-353 (Korea, Republic of); Lee, H. Y.; Jo, J. G.; Hwang, Y. S. [Seoul National University, Seoul 151-742 (Korea, Republic of)

    2014-06-15

    The XB mode conversion in electron cyclotron resonance frequency heating has been studied in detail through 1D full wave simulation. The field pattern depends on the density scale length, and the wave absorption near upper hybrid resonance is maximized beyond the R(X) mode cutoff density for optimized density scale length. The simulated mode conversion efficiency has been compared with that of an analytic formula, showing good agreements except for the phase dependent term of the X wave. The mode conversion efficiency is calculated for oblique injections as well, and it is found that the efficiency decreases as the injection angles increases. Short magnetic field scale length is confirmed to relax the short density scale length condition maximizing the XB mode conversion efficiency. Finally, the simulation code is used to analyze the mode conversion and power absorption of a pre-ionization plasma in versatile experiment spherical torus.

  5. Enhancing critical current density of cuprate superconductors

    DOE Patents [OSTI]

    Chaudhari, Praveen

    2015-06-16

    The present invention concerns the enhancement of critical current densities in cuprate superconductors. Such enhancement of critical current densities include using wave function symmetry and restricting movement of Abrikosov (A) vortices, Josephson (J) vortices, or Abrikosov-Josephson (A-J) vortices by using the half integer vortices associated with d-wave symmetry present in the grain boundary.

  6. 2011 Waves -1 STANDING WAVES

    E-Print Network [OSTI]

    Gustafsson, Torgny

    2011 Waves - 1 STANDING WAVES ON A STRING The objectives of the experiment are: · To show that standing waves can be set up on a string. · To determine the velocity of a standing wave. · To understand of waves. A #12;2011 Waves - 2 A standing wave is caused by superposing two similar (same frequency

  7. Propagating Waves in a Monolayer of Gas-Fluidized Rods

    E-Print Network [OSTI]

    L. J. Daniels; D. J. Durian

    2010-11-12

    We report on an observation of propagating compression waves in a quasi-two-dimensional monolayer of apolar granular rods fluidized by an upflow of air. The collective wave speed is an order of magnitude faster than the speed of the particles. This gives rise to anomalously large number fluctuations dN ~ $N^{0.72 \\pm 0.04}$, which are greater than ordinary number fluctuations of N^{1/2}. We characterize the waves by calculating the spatiotemporal power spectrum of the density. The position of observed peaks, as a function of frequency w and wavevector k, yields a linear dispersion relationship in the long-time, long-wavelength limit and a wavespeed c = w/k. Repeating this analysis for systems at different densities and air speeds, we observe a linear increase in the wavespeed with increasing packing fraction with no dependence on the airflow. Although air-fluidized rods self-propel individually or in dilute collections, the parallel and perpendicular root-mean-square speeds of the rods indicate that they no longer self-propel when propagating waves are present. Based on this mutual exclusivity, we map out the phase behavior for the existence of waves vs self-propulsion as a function of density and fluidizing airflow.

  8. Arnold Schwarzenegger CALIFORNIA OCEAN WAVE

    E-Print Network [OSTI]

    Arnold Schwarzenegger Governor CALIFORNIA OCEAN WAVE ENERGY ASSESSMENT Prepared For: California, State and Federal Agencies and their expectations in respect to potential wave power deployments Jim a huge amount of wave measurement data from various data sources Asfaw Beyene of the Department

  9. Numerical simulations of acoustically generated gravitational waves at a first order phase transition

    E-Print Network [OSTI]

    Hindmarsh, Mark; Rummukainen, Kari; Weir, David J

    2015-01-01

    We present details of numerical simulations of the gravitational radiation produced by a first order {thermal} phase transition in the early universe. We confirm that the dominant source of gravitational waves is sound waves generated by the expanding bubbles of the low-temperature phase. We demonstrate that the sound waves have a power spectrum with power-law form between the scales set by the average bubble separation (which sets the length scale of the fluid flow $L_\\text{f}$) and the bubble wall width. The sound waves generate gravitational waves whose power spectrum also has a power-law form, at a rate proportional to $L_\\text{f}$ and the square of the fluid kinetic energy density. We identify a dimensionless parameter $\\tilde\\Omega_\\text{GW}$ characterising the efficiency of this "acoustic" gravitational wave production whose value is $8\\pi\\tilde\\Omega_\\text{GW} \\simeq 0.8 \\pm 0.1$ across all our simulations. We compare the acoustic gravitational waves with the standard prediction from the envelope appr...

  10. Propagating Structure Of A Microwave Driven Shock wave Inside A Tube

    SciTech Connect (OSTI)

    Shimada, Yutaka; Shibata, Teppei; Yamaguchi, Toshikazu; Komurasaki, Kimiya [Department of Advanced Energy, the University of Tokyo, 5-1-5 Kashiwa-no-ha, Kashiwa, Chiba, 277-8561 (Japan); Oda, Yasuhisa; Kajiwara, Ken; Takahashi, Koji; Kasugai, Atsushi; Sakamoto, Keishi [Japan Atomic Energy Agency, 801-1 Mukoyama, Naka, Ibaraki, 311-0193 (Japan); Arakawa, Yoshihiro [Department of Aeronautics and Astronautics, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-0033 (Japan)

    2010-05-06

    The thrust generation process of a microwave rocket is similar to a pulse detonation engine, and understanding the interactions between microwave plasma and shock waves is important. Shadowgraph images of the microwave plasma generated in a tube under atmospheric air were taken. The observed plasma and shock wave were propagating one-dimensionally at constant velocity inside the tube. In order to understand the flow field inside the rocket, one-dimensional CFD analysis was conducted. With the change of microwave power density, the structure of the flow field was classified into two regimes: Microwave Supported Combustion (MSC), and Microwave Supported Detonation (MSD). The structure of the MSD was different from the structure of a chemical detonation, which implied the existence of a preheating in front of the shock wave. Furthermore, the flight performance was estimated by calculating the momentum coupling coefficient. It was confirmed that the efficiency was nearly constant in the MSD regime, with the increase of microwave power density.

  11. MHK Technologies/New Knowledge Wind and Wave Renewable Mobile...

    Open Energy Info (EERE)

    < MHK Technologies Jump to: navigation, search << Return to the MHK database homepage New Knowledge Wind and Wave Renewable Mobile Wind and Wave Power Plant Platform.jpg...

  12. Quantum coherent switch utilizing commensurate nanoelectrode and charge density periodicities

    DOE Patents [OSTI]

    Harrison; Neil (Santa Fe, NM), Singleton; John (Los Alamos, NM), Migliori; Albert (Santa Fe, NM)

    2008-08-05

    A quantum coherent switch having a substrate formed from a density wave (DW) material capable of having a periodic electron density modulation or spin density modulation, a dielectric layer formed onto a surface of the substrate that is orthogonal to an intrinsic wave vector of the DW material; and structure for applying an external spatially periodic electrostatic potential over the dielectric layer.

  13. Density modification by two superposing TE{sub 10} modes in a plasma filled rectangular waveguide

    SciTech Connect (OSTI)

    Tomar, Sanjay K.; Malik, Hitendra K. [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)] [Plasma Waves and Particle Acceleration Laboratory, Department of Physics, Indian Institute of Technology Delhi, New Delhi 110 016 (India)

    2013-07-15

    Microwave and plasma interaction is examined via two fundamental TE{sub 10} modes propagating in a plasma filled rectangular waveguide after superposing at a smaller angle. The propagation of the resultant mode realized from these two modes is governed by a wave equation obtained using the Maxwell's equations. This equation is solved numerically using fourth order Runge-Kutta method for the field amplitude of the microwave in the waveguide considering the waveguide to be made up of a perfect conductor and filled with different types of initial plasma density distributions, viz. homogeneous density, linear density with gradient in the propagation direction, and the density with Gaussian profile along the waveguide width. A phenomenon similar to the duct formation by high power microwaves is found to take place, where the plasma density attains interesting profiles. These profiles can be controlled by the angle of superposition, phase difference between the fields of the two modes, microwave frequency and microwave field amplitude.

  14. Wave Motion

    E-Print Network [OSTI]

    M. Carcione, F. Cavallini, Simulation of waves in porn-viscoelastic rocks Saturated by immiscible ?uids. Numerical evidence ofa second slow wave,]. Comput.

  15. Stratified Steady Periodic Water Waves

    E-Print Network [OSTI]

    Samuel Walsh

    2009-02-11

    This paper considers two-dimensional stratified water waves propagating under the force of gravity over an impermeable flat bed and with a free surface. We prove the existence of a global continuum of classical solutions that are periodic and traveling. These waves, moreover, can exhibit large density variation, speed and amplitude.

  16. Millimeter-Wave Circuits for 60GHz and Beyond

    E-Print Network [OSTI]

    Afshar, Bagher

    2010-01-01

    Device Modeling for mm-Wave Design . . . . . . . . . .Devices for mm-Wave Design . . . . . . . . . . . . . .9.2 Previous Work on mm-Wave Power Ampli?ers in SiGe

  17. A Comprehensive Study Of Fracture Patterns And Densities In The...

    Open Energy Info (EERE)

    Patterns And Densities In The Geysers Geothermal Reservoir Using Microearthquake Shear-Wave Splitting Tomography Jump to: navigation, search OpenEI Reference LibraryAdd to...

  18. Sandia Energy - Advanced Controls of Wave Energy Converters May...

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

    Advanced Controls of Wave Energy Converters May Increase Power Capture Up to 330% Home Renewable Energy Energy Water Power Partnership News News & Events Computational Modeling &...

  19. Spatiotemporal temperature and density characterization of high-power atmospheric flashover discharges over inert poly(methyl methacrylate) and energetic pentaerythritol tetranitrate dielectric surfaces

    SciTech Connect (OSTI)

    Tang, V.; Grant, C. D.; McCarrick, J. F.; Zaug, J. M.; Glascoe, E. A.; Wang, H.

    2012-03-01

    A flashover arc source that delivered up to 200 mJ on the 100s-of-ns time-scale to the arc and a user-selected dielectric surface was characterized for studying high-explosive kinetics under plasma conditions. The flashover was driven over thin pentaerythritol tetranitrate (PETN) and poly(methyl methacrylate) (PMMA) dielectric films and the resultant plasma was characterized in detail. Time- and space-resolved temperatures and electron densities of the plasma were obtained using atomic emission spectroscopy. The hydrodynamics of the plasma was captured through fast, visible imaging. Fourier transform infrared spectroscopy (FTIR) was used to characterize the films pre- and post-shot for any chemical alterations. Time-resolved infrared spectroscopy (TRIR) provided PETN depletion data during the plasma discharge. For both types of films, temperatures of 1.6-1.7 eV and electron densities of {approx}7-8 x 10{sup 17}/cm{sup 3}{approx}570 ns after the start of the discharge were observed with temperatures of 0.6-0.7 eV persisting out to 15 {mu}s. At 1.2 {mu}s, spatial characterization showed flat temperature and density profiles of 1.1-1.3 eV and 2-2.8 x 10{sup 17}/cm{sup 3} for PETN and PMMA films, respectively. Images of the plasma showed an expanding hot kernel starting from radii of {approx}0.2 mm at {approx}50 ns and reaching {approx}1.1 mm at {approx}600 ns. The thin films ablated or reacted several hundred nm of material in response to the discharge. First TRIR data showing the in situ reaction or depletion of PETN in response to the flashover arc were successfully obtained, and a 2-{mu}s, 1/e decay constant was measured. Preliminary 1 D simulations compared reasonably well with the experimentally determined plasma radii and temperatures. These results complete the first steps to resolving arc-driven PETN reaction pathways and their associated kinetic rates using in situ spectroscopy techniques.

  20. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, Vincent M. (Placitas, NM); Vawter, Gregory A. (Albuquerque, NM)

    1993-01-01

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.

  1. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, V.M.; Vawter, G.A.

    1993-12-14

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size. 4 figures.

  2. Dispersive shock waves in interacting one-dimensional systems

    E-Print Network [OSTI]

    Fominov, Yakov

    (internal waves in deep stratified fluid) Benjamin 1967 Ono 1975 Benjamin-Ono KdV h H #12;Nonlinearity vs · Internal waves in deep stratified fluids · Atmosphere waves www.dropbears.com #12;Conventional shock waves + l0 x + 2 l0xx H = 0 soliton charge = 1 m = Consequence of the universal density profile! m=3

  3. One dimensional full wave analysis of slow-to-fast mode conversion in lower hybrid frequencies

    SciTech Connect (OSTI)

    Jia, Guo-Zhang; Gao, Zhe

    2014-12-15

    The linear conversion from the slow wave to the fast wave in the lower hybrid range of frequencies is analyzed numerically by using the set of field equations describing waves in a cold plane-stratified plasma. The equations are solved as a two-point boundary value problem, where the polarizations of each mode are set consistently in the boundary conditions. The scattering coefficients and the field patterns are obtained for various density profiles. It is shown that, for large density scale length, the results agree well with the traditional cognitions. In contrast, the reflected component and the probable transmitted-converted component from the conversion region, which are neglected in the usual calculations, become significant when the scale length is smaller than the wavelength of the mode. The inclusion of these new components will improve the accuracy of the simulated propagation and deposition for the injected rf power when the conversion process is involved within a sharp-varying density profile. Meanwhile, the accessibility of the incident slow wave for the low frequency case is also affected by the scale length of the density profile.

  4. Climate modulates internal wave activity in the Northern South China Sea

    E-Print Network [OSTI]

    Decarlo, TM; Karnauskas, KB; Davis, KA; Wong, GTF

    2015-01-01

    of nonlinear internal wave generation and propagation in theof generation mechanisms of solitary internal waves in theWaves The background oceanic density ?eld has both spatial and temporal variability, which can affect IW generation

  5. Energy Transfer via Solar Wind Driven Ultra Low Frequency Waves in the Earth's Magnetosphere

    E-Print Network [OSTI]

    Hartinger, Michael David

    2012-01-01

    spectral density comparison Wave polarization and energythe plasmasphere on ULF wave energy transfer. We conclude inan important e?ect on ULF wave energy transfer in the Pc5

  6. Wave represents displacement Wave represents pressure Source -Sound Waves

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio. The Sound Waves simulation becomes the source of an analogical mapping to Radio Waves. Concepts Radio Waves 1 - Sound Waves references water waves 2 - Water is analogy for Sound Waves 3 - Radio

  7. POWER, THERMAL, AND RELIABILITY MODELING IN NANOMETER-SCALE

    E-Print Network [OSTI]

    Brooks, David

    ........................................................................................................................................................................................................................................................ POWER ........................................................................................................................................................................................................................................................ POWER IS THE SOURCE OF THE GREATEST PROBLEMS FACING MICROPROCESSOR DESIGNERS. RAPID POWER VARIATION BRINGS TRANSIENT ERRORS. HIGH POWER DENSITIES BRING HIGH TEMPERATURES, HARMING RELIABILITY AND INCREASING

  8. Traveling wave device for combining or splitting symmetric and asymmetric waves

    DOE Patents [OSTI]

    Möbius, Arnold (Eggenstein, DE); Ives, Robert Lawrence (Saratoga, CA)

    2005-07-19

    A traveling wave device for the combining or splitting of symmetric and asymmetric traveling wave energy includes a feed waveguide for traveling wave energy, the feed waveguide having an input port and a launching port, a reflector for coupling wave energy between the feed waveguide and a final waveguide for the collection and transport of wave energy to or from the reflector. The power combiner has a launching port for symmetrical waves which includes a cylindrical section coaxial to the feed waveguide, and a launching port for asymmetric waves which includes a sawtooth rotated about a central axis.

  9. Low-Density Attack Revisited Tetsuya Izu

    E-Print Network [OSTI]

    International Association for Cryptologic Research (IACR)

    Low-Density Attack Revisited Tetsuya Izu Jun Kogure Takeshi Koshiba Takeshi Shimoyama Secure The low-density attack proposed by Lagarias and Odlyzko is a powerful algorithm against the subset sum, densities of the subset sum problems should be higher than 0.9408... in order to avoid the low

  10. Low density metal hydride foams

    DOE Patents [OSTI]

    Maienschein, Jon L. (Oakland, CA); Barry, Patrick E. (Pleasant Hill, CA)

    1991-01-01

    Disclosed is a low density foam having a porosity of from 0 to 98% and a density less than about 0.67 gm/cc, prepared by heating a mixture of powered lithium hydride and beryllium hydride in an inert atmosphere at a temperature ranging from about 455 to about 490 K for a period of time sufficient to cause foaming of said mixture, and cooling the foam thus produced. Also disclosed is the process of making the foam.

  11. ELECTROCHEMICAL POWER FOR TRANSPORTATION

    E-Print Network [OSTI]

    Cairns, Elton J.

    2012-01-01

    The idea of using fuel cells as a high-efficiency source offuel cell) E V; 6094 W·h/kga Theoretical References Specific Power 27-25 W/kg Power Density 12-35 W/1 Efficiency

  12. High Energy Density Capacitors

    SciTech Connect (OSTI)

    2010-07-01

    BEEST Project: Recapping is developing a capacitor that could rival the energy storage potential and price of today’s best EV batteries. When power is needed, the capacitor rapidly releases its stored energy, similar to lightning being discharged from a cloud. Capacitors are an ideal substitute for batteries if their energy storage capacity can be improved. Recapping is addressing storage capacity by experimenting with the material that separates the positive and negative electrodes of its capacitors. These separators could significantly improve the energy density of electrochemical devices.

  13. CONTROL OF POPULATION DENSITIES SURROUNDING NUCLEAR POWER PLANTS. VOLUME 5 OF THE FINAL REPORT ON HEALTH AND SAFETY IMPACTS OF NUCLEAR, GEOTHERMAL, AND FOSSIL-FUEL ELECTRIC GENERATION IN CALIFORNIA

    E-Print Network [OSTI]

    Nero, jA.V.

    2010-01-01

    the actual risk presented by nuclear power plants. Dependingyears): Average risk from a nuclear power plant during itssocietal risks from a system of 100 nuclear power plants due

  14. Whistler mode waves and the electron heat flux in the solar wind: cluster observations

    SciTech Connect (OSTI)

    Lacombe, C.; Alexandrova, O.; Cornilleau-Wehrlin, N.; Mangeney, A.; De Conchy, Y.; Maksimovic, M.; Matteini, L.; Santolík, O.

    2014-11-20

    The nature of the magnetic field fluctuations in the solar wind between the ion and electron scales is still under debate. Using the Cluster/STAFF instrument, we make a survey of the power spectral density and of the polarization of these fluctuations at frequencies f in [1, 400] Hz, during five years (2001-2005), when Cluster was in the free solar wind. In ?10% of the selected data, we observe narrowband, right-handed, circularly polarized fluctuations, with wave vectors quasi-parallel to the mean magnetic field, superimposed on the spectrum of the permanent background turbulence. We interpret these coherent fluctuations as whistler mode waves. The lifetime of these waves varies between a few seconds and several hours. Here, we present, for the first time, an analysis of long-lived whistler waves, i.e., lasting more than five minutes. We find several necessary (but not sufficient) conditions for the observation of whistler waves, mainly a low level of background turbulence, a slow wind, a relatively large electron heat flux, and a low electron collision frequency. When the electron parallel beta factor ? {sub e?} is larger than 3, the whistler waves are seen along the heat flux threshold of the whistler heat flux instability. The presence of such whistler waves confirms that the whistler heat flux instability contributes to the regulation of the solar wind heat flux, at least for ? {sub e?} ? 3, in slow wind at 1 AU.

  15. Plasma control by modification of helicon wave propagation in low magnetic fields

    SciTech Connect (OSTI)

    Lafleur, T.; Charles, C.; Boswell, R. W. [Space Plasma, Power and Propulsion Group, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2010-07-15

    By making use of nonuniform magnetic fields, it is shown experimentally that control of helicon wave propagation can be achieved in a low pressure (0.08 Pa) expanding plasma. The m=1 helicon waves are formed during a direct capacitive to wave mode transition that occurs in a low diverging magnetic field (B{sub 0}<3 mT). In this initial configuration, waves are prevented from reaching the downstream region, but slight modifications to the magnetic field allows the axial distance over which waves can propagate to be controlled. By changing the effective propagation distance in this way, significant modification of the density and plasma potential profiles can be achieved, showing that the rf power deposition can be spatially controlled as well. Critical to the modification of the wave propagation behavior is the magnetic field strength (and geometry) near the exit of the plasma source region, which gives electron cyclotron frequencies close to the wave frequency of 13.56 MHz.

  16. Matter Wave Radiation Leading to Matter Teleportation

    E-Print Network [OSTI]

    Yong-Yi Huang

    2015-02-12

    The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.

  17. Vacuum Waves

    E-Print Network [OSTI]

    Paul S. Wesson

    2012-12-11

    As an example of the unification of gravitation and particle physics, an exact solution of the five-dimensional field equations is studied which describes waves in the classical Einstein vacuum. While the solution is essentially 5D in nature, the waves exist in ordinary 3D space, and may provide a way to test for an extra dimension.

  18. Ultra high vacuum broad band high power microwave window

    DOE Patents [OSTI]

    Nguyen-Tuong, Viet (Seaford, VA); Dylla, III, Henry Frederick (Yorktown, VA)

    1997-01-01

    An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost.

  19. Ultra high vacuum broad band high power microwave window

    DOE Patents [OSTI]

    Nguyen-Tuong, V.; Dylla, H.F. III

    1997-11-04

    An improved high vacuum microwave window has been developed that utilizes high density polyethylene coated on two sides with SiOx, SiNx, or a combination of the two. The resultant low dielectric and low loss tangent window creates a low outgassing, low permeation seal through which broad band, high power microwave energy may be passed. No matching device is necessary and the sealing technique is simple. The features of the window are broad band transmission, ultra-high vacuum compatibility with a simple sealing technique, low voltage standing wave ratio, high power transmission and low cost. 5 figs.

  20. Ulysses observations of magnetic waves due to newborn interstellar pickup ions. I. New observations and linear analysis

    SciTech Connect (OSTI)

    Cannon, Bradford E.; Smith, Charles W.; Isenberg, Philip A.; Vasquez, Bernard J.; Murphy, Neil; Nuno, Raquel G. E-mail: Charles.Smith@unh.edu E-mail: Bernie.Vasquez@unh.edu E-mail: raquel.nuno@asu.edu

    2014-04-01

    We have examined Ulysses magnetic field data using dynamic spectrogram techniques that compute wave amplitude, polarization, and direction of propagation over a broad range of frequencies and time. Events were identified that showed a strong polarization signature and an enhancement of power above the local proton gyrofrequency. We perform a statistical study of 502 wave events in an effort to determine when, where, and why they are observed. Most notably, we find that waves arising from newborn interstellar pickup ions are relatively rare and difficult to find. The quantities normally employed in theories of wave growth are neutral atom density and quantities related to their ionization and the subsequent dynamics such as wind speed, solar wind flux, and magnetic field orientation. We find the observations of waves to be largely uncorrelated to these quantities except for mean field direction where quasi-radial magnetic fields are favored and solar wind proton flux where wave observations appear to be favored by low flux conditions which runs contrary to theoretical expectations of wave generation. It would appear that an explanation based on source physics and instability growth rates alone is not adequate to account for the times when these waves are seen.

  1. On the Energy of Rotating Gravitational Waves

    E-Print Network [OSTI]

    Bahram Mashhoon; James C. McClune; Enrique Chavez; Hernando Quevedo

    1996-09-06

    A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.

  2. Nonlinear interaction of proton whistler with kinetic Alfvén wave to study solar wind turbulence

    SciTech Connect (OSTI)

    Goyal, R.; Sharma, R. P.; Goldstein, M. L.; Dwivedi, N. K.

    2013-12-15

    This paper presents the nonlinear interaction between small but finite amplitude kinetic Alfvén wave (KAW) and proton whistler wave using two-fluid model in intermediate beta plasma, applicable to solar wind. The nonlinearity is introduced by modification in the background density. This change in density is attributed to the nonlinear ponderomotive force due to KAW. The solutions of the model equations, governing the nonlinear interaction (and its effect on the formation of localized structures), have been obtained using semi-analytical method in solar wind at 1AU. It is concluded that the KAW properties significantly affect the threshold field required for the filament formation and their critical size (for proton whistler). The magnetic and electric field power spectra have been obtained and their relevance with the recent observations of solar wind turbulence by Cluster spacecraft has been pointed out.

  3. Gravitational wave production by rotating primordial black holes

    E-Print Network [OSTI]

    Dong, Ruifeng; Stojkovic, Dejan

    2015-01-01

    In this paper we analyze in detail a rarely discussed question of gravity waves production from evaporating black holes. Evaporating black holes emit gravitons which are at classical level registered as gravity waves. We use the latest constraints on the primordial black hole abundance, and calculate the power emitted in gravitons at the time of their evaporation. We then solve the coupled system of equations that gives us the evolution of the frequency and amplitude of gravity waves during the expansion of the universe. The spectrum of gravitational waves that can be detected today depends on multiple factors: fraction of the total energy density which was occupied by black holes, the epoch in which the black holes are formed, and quantities like mass and angular momentum of evaporating black holes. We conclude that very small primordial black holes which evaporate before the nucleosynthesis emit gravitons whose spectral energy fraction today can be as large as $10^{-5}$. On the other hand, primordial black ...

  4. The Centre for Power Transmission

    E-Print Network [OSTI]

    Burton, Geoffrey R.

    . The PTMC strives to be a distinguished centre of excellence for wave power technology. The combination and make it a serious competitor for other renewable energy technologies. #12;) 1225 38-6371 Email: ptmc@bath.ac.uk Web: http://www.bath.ac.uk/ptmc/ Consultancy Project WAVE POWER

  5. Primordial Graviton Production and Decaying Vacuum Energy Density

    E-Print Network [OSTI]

    Tamayo, David; Bessada, D F A

    2015-01-01

    The problem of cosmological production of (massless) gravitons is discussed in the framework of an expanding, spatially homogeneous and isotropic FRW type Universe with decaying vacuum energy density ($\\Lambda \\equiv \\Lambda(H(t))$) described by general relativity theory. The gravitational wave equation is established and its time-dependent part has analytically been solved for different epochs in the case of a flat geometry. Unlike the standard $\\Lambda$CDM cosmology (no interacting vacuum), we show that massless gravitons can be produced during the radiation era. However, high frequency modes are damped out even faster than in the standard cosmology both in the radiation and matter-vacuum dominated epoch. The formation of the stochastic background of gravitons and the remnant power spectrum generated at different cosmological eras are also explicitly evaluated.

  6. CONTROL OF POPULATION DENSITIES SURROUNDING NUCLEAR POWER PLANTS. VOLUME 5 OF THE FINAL REPORT ON HEALTH AND SAFETY IMPACTS OF NUCLEAR, GEOTHERMAL, AND FOSSIL-FUEL ELECTRIC GENERATION IN CALIFORNIA

    E-Print Network [OSTI]

    Nero, jA.V.

    2010-01-01

    Standards for Nuclear Power Plants," by A.V. Nero and Y.C.Planning for Nuclear Power Plants in California," by W.W.S.Surrounding Nuclear Power Plants," by A.V. Nero, C.H.

  7. Structural vibration damping using lightweight, low-wave-speed media

    E-Print Network [OSTI]

    Verdirame, Justin Matthew, 1978-

    2007-01-01

    Incorporation of a low-density, low-wave-speed medium (LWSM) into a structure yields significant damping if the speed of wave propagation in the medium is low enough for standing waves to arise in it. In this thesis, we ...

  8. Peculiarities in the energy transfer by waves on strained strings

    E-Print Network [OSTI]

    Butikov, Eugene

    Peculiarities in the energy transfer by waves on strained strings Eugene I. Butikov St. Petersburg of elastic potential energy associated with waves in a stretched string is discussed. The influence of nonlinear coupling between transverse and longitudinal waves on the density of energy is investigated

  9. Development of PTO-Sim: A Power Performance Module for the Open-Source Wave Energy Converter Code WEC-Sim

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalent BondingMeeting |DesignCommunities ReviewedOilDevelopment

  10. Spin waves in the (

    SciTech Connect (OSTI)

    Lipscombe, O. J.; Chen, G. F.; Fang, Chen; Perring, T. G.; Abernathy, Douglas L; Christianson, Andrew D; Egami, Takeshi; Wang, Nanlin; Hu, Jiangping; Dai, Pengcheng

    2011-01-01

    We use neutron scattering to show that spin waves in the iron chalcogenide Fe{sub 1.05}Te display novel dispersion clearly different from both the first principles density functional calculations and recent observations in the related iron pnictide CaFe{sub 2}As{sub 2}. By fitting to a Heisenberg Hamiltonian, we find that although the nearest-neighbor exchange couplings in the two systems are quite different, their next-nearest-neighbor (NNN) couplings are similar. This suggests that superconductivity in the pnictides and chalcogenides share a common magnetic origin that is intimately associated with the NNN magnetic coupling between the irons.

  11. Wave Propagation in Multiferroic Materials

    E-Print Network [OSTI]

    Keller, Scott Macklin

    2013-01-01

    130 SAW Waves . . . . . . . . . . . . . .QuasiStatic MEE Waves . . . . . . . . . . . . . . . . . . .General MEE Wave Solution . . . . . . . . . . . .

  12. TEMPORAL VARIATIONS OF FRACTURE DIRECTIONS AND FRACTURE DENSITIES...

    Open Energy Info (EERE)

    DIRECTIONS AND FRACTURE DENSITIES IN THE COSO GEOTHERMAL FIELD FROM ANALYSES OF SHEAR-WAVE SPLITTING Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference...

  13. The Wave Function and Quantum Reality

    E-Print Network [OSTI]

    Shan Gao

    2011-08-04

    We investigate the meaning of the wave function by analyzing the mass and charge density distribution of a quantum system. According to protective measurement, a charged quantum system has mass and charge density proportional to the modulus square of its wave function. It is shown that the mass and charge density is not real but effective, and it is formed by the ergodic motion of a localized particle with the total mass and charge of the system. Moreover, it is argued that the ergodic motion is not continuous but discontinuous and random. This result suggests a new interpretation of the wave function, according to which the wave function is a description of random discontinuous motion of particles, and the modulus square of the wave function gives the probability density of the particles being in certain locations. It is shown that the suggested interpretation of the wave function disfavors the de Broglie-Bohm theory and the many-worlds interpretation but favors the dynamical collapse theories, and the random discontinuous motion of particles may provide an appropriate random source to collapse the wave function.

  14. Common Analysis of the Relativistic Klystron and the Standing-Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Wurtele, Jonathan S.

    2008-01-01

    Powered by a Relativistic Klystron", Phys. Rev. Lett. 11.Analysis the Relativistic Klystron and the Standing-WaveANALYSIS OF THE RELATIVISTIC KLYSTRON AND THE STANDING-WAVE

  15. Internal wave instability: Wave-wave versus wave-induced mean flow interactions

    E-Print Network [OSTI]

    Sutherland, Bruce

    Internal wave instability: Wave-wave versus wave-induced mean flow interactions B. R. Sutherland fluid, vertically propagating internal gravity waves of moderately large amplitude can become unstable, energy from primary waves is transferred, for example, to waves with half frequency. Self

  16. Author's personal copy Wave energy resources along the Hawaiian Island chain

    E-Print Network [OSTI]

    Author's personal copy Wave energy resources along the Hawaiian Island chain Justin E. Stopa model Wave atlas Wave energy Wave power a b s t r a c t Hawaii's access to the ocean and remoteness from as nearshore wave energy resources in Hawaii. A global WAVEWATCH III (WW3) model forced by surface winds from

  17. Electron Bernstein Wave Research on the National Spherical Torus Experiment

    SciTech Connect (OSTI)

    G. Taylor; A. Bers; T.S. Bigelow; M.D. Carter; J.B. Caughman; J. Decker; S. Diem; P.C. Efthimion; N.M. Ershov; E. Fredd; R.W. Harvey; J. Hosea; F. Jaeger; J. Preinhaelter; A.K. Ram; D.A. Rasmussen; A.P. Smirnov; J.B. Wilgen; J.R. Wilson

    2005-04-21

    Off-axis electron Bernstein wave current drive (EBWCD) may be critical for sustaining noninductive high-beta National Spherical Torus Experiment (NSTX) plasmas. Numerical modeling results predict that the {approx}100 kA of off-axis current needed to stabilize a solenoid-free high-beta NSTX plasma could be generated via Ohkawa current drive with 3 MW of 28 GHz EBW power. In addition, synergy between EBWCD and bootstrap current may result in a 10% enhancement in current-drive efficiency with 4 MW of EBW power. Recent dual-polarization EBW radiometry measurements on NSTX confirm that efficient coupling to EBWs can be readily accomplished by launching elliptically polarized electromagnetic waves oblique to the confining magnetic field, in agreement with numerical modeling. Plans are being developed for implementing a 1 MW, 28 GHz proof-of-principle EBWCD system on NSTX to test the EBW coupling, heating and current-drive physics at high radio-frequency power densities.

  18. Gravitational Waves from Neutron Stars: A Review

    E-Print Network [OSTI]

    Paul D. Lasky

    2015-08-26

    Neutron stars are excellent emitters of gravitational waves. Squeezing matter beyond nuclear densities invites exotic physical processes, many of which violently transfer large amounts of mass at relativistic velocities, disrupting spacetime and generating copious quantities of gravitational radiation. I review mechanisms for generating gravitational waves with neutron stars. This includes gravitational waves from radio and millisecond pulsars, magnetars, accreting systems and newly born neutron stars, with mechanisms including magnetic and thermoelastic deformations, various stellar oscillation modes and core superfluid turbulence. I also focus on what physics can be learnt from a gravitational wave detection, and where additional research is required to fully understand the dominant physical processes at play.

  19. Gravitational Waves from Neutron Stars: A Review

    E-Print Network [OSTI]

    Lasky, Paul D

    2015-01-01

    Neutron stars are excellent emitters of gravitational waves. Squeezing matter beyond nuclear densities invites exotic physical processes, many of which violently transfer large amounts of mass at relativistic velocities, disrupting spacetime and generating copious quantities of gravitational radiation. I review mechanisms for generating gravitational waves with neutron stars. This includes gravitational waves from radio and millisecond pulsars, magnetars, accreting systems and newly born neutron stars, with mechanisms including magnetic and thermoelastic deformations, various stellar oscillation modes and core superfluid turbulence. I also focus on what physics can be learnt from a gravitational wave detection, and where additional research is required to fully understand the dominant physical processes at play.

  20. Emergence of exponentially small reflected waves

    E-Print Network [OSTI]

    Volker Betz; Alain Joye; Stefan Teufel

    2008-04-23

    We study the time-dependent scattering of a quantum mechanical wave packet at a barrier for energies larger than the barrier height, in the semi-classical regime. More precisely, we are interested in the leading order of the exponentially small scattered part of the wave packet in the semiclassical parameter when the energy density of the incident wave is sharply peaked around some value. We prove that this reflected part has, to leading order, a Gaussian shape centered on the classical trajectory for all times soon after its birth time. We give explicit formulas and rigorous error bounds for the reflected wave for all of these times.

  1. TRAVELING-WAVE TUBE AMPLIFIER CHARACTERISTICS STUDY FOR STOCHASTIC BEAM COOLING EXPERIMENTS

    E-Print Network [OSTI]

    Leskovar, B.

    2010-01-01

    Power Gallium-Arsenide Field- Effect Transistors and Helix Traveling-Wave Tubes (TWT) were considered as potential

  2. Status of High Power Tests of Normal Conducting Short Standing...

    Office of Scientific and Technical Information (OSTI)

    Status of High Power Tests of Normal Conducting Short Standing Wave Structures Citation Details In-Document Search Title: Status of High Power Tests of Normal Conducting Short...

  3. Shallow Water Waves and Solitary Waves

    E-Print Network [OSTI]

    Hereman, Willy

    2013-01-01

    Encyclopedic article covering shallow water wave models used in oceanography and atmospheric science. Sections: Definition of the Subject; Introduction and Historical Perspective; Completely Integrable Shallow Water Wave Equations; Shallow Water Wave Equations of Geophysical Fluid Dynamics; Computation of Solitary Wave Solutions; Numerical Methods; Water Wave Experiments and Observations; Future Directions, and Bibliography.

  4. Energy Department Invests $16 Million to Harness Wave and Tidal...

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

    wave conditions and adjust system settings to maximize power output. Responsible and Sustainable Energy Development As part of the Administration's commitment to developing...

  5. Sandia Energy - Sandia, NREL Release Wave Energy Converter Modeling...

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

    Release Wave Energy Converter Modeling and Simulation Code: WEC-Sim Home Renewable Energy Energy Water Power Partnership News News & Events Computational Modeling & Simulation...

  6. Stochastic excitation of seismic waves by a hurricane

    E-Print Network [OSTI]

    Tanimoto, Toshiro

    2015-01-01

    J. Kossin (2008), Increasing hurricane wave power along thescale characteristics of mature hurricanes. Part I: GeneralVertical motions in intense hurricanes, J. Atmos. Sci. , 42,

  7. Wind Power

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

    Wind Power Bioenergy Power Systems Wind Power Wind Power Main Page Outreach Programs Image Gallery FAQs Links Software Hydro Power INL Home Wind Power Introduction The Wind Power...

  8. Alfven wave tomography for cold magnetohydrodynamic plasmas I. Y. Dodin and N. J. Fisch

    E-Print Network [OSTI]

    ARTICLES Alfve´n wave tomography for cold magnetohydrodynamic plasmas I. Y. Dodin and N. J. Fisch; accepted 12 December 2001 Alfve´n wave propagation in slightly nonuniform cold plasmas is studied by means of quasistatic plasma density perturbations. The Alfve´n waves are shown not to affect the plasma density

  9. Controller for a wave energy converter

    DOE Patents [OSTI]

    Wilson, David G.; Bull, Diana L.; Robinett, III, Rush D.

    2015-09-22

    A wave energy converter (WEC) is described, the WEC including a power take off (PTO) that converts relative motion of bodies of the WEC into electrical energy. A controller controls operation of the PTO, causing the PTO to act as a motor to widen a wave frequency spectrum that is usable to generate electrical energy.

  10. Traveling Waves in Lattice Dynamical Systems

    E-Print Network [OSTI]

    a number of other potentials, like the power potential, the Lennard­Jones potential, etc., which cases). In the case of a general superquadratic potential, the first rigorous study of traveling waves with prescribed av­ eraged potential energy. Then the wave speed c is determined in terms of the corresponding

  11. Zero Energy of Plane-Waves for ELKOs

    E-Print Network [OSTI]

    Luca Fabbri

    2011-02-23

    We consider the ELKO field in interaction through contorsion with its own spin density, and we investigate the form of the consequent autointeractions; to do so we take into account the high-density limit and find plane wave solutions: such plane waves give rise to contorsional autointeractions for which the Ricci metric curvature vanishes and therefore the energy density is equal to zero identically. Consequences are discussed.

  12. MHD Wave Propagation in the Neighbourhood of Two Null Points

    E-Print Network [OSTI]

    J. A. McLaughlin; A. W. Hood

    2007-12-11

    The nature of fast magnetoacoustic and Alfv\\'en waves is investigated in a zero $\\beta$ plasma in the neighbourhood of a pair of two-dimensional null points. This gives an indication of wave propagation in the low $\\beta$ solar corona, for a more complicated magnetic configuration than that looked at by McLaughlin & Hood (2004). It is found that the fast wave is attracted to the null points and that the front of the wave slows down as it approaches the null point pair, with the wave splitting and part of the wave accumulating at one null and the rest at the other. Current density will then accumulate at these points and ohmic dissipation will then extract the energy in the wave at these points. This suggests locations where wave heating will occur in the corona. The Alfv\\'en wave behaves in a different manner in that the wave accumulates along the separatrices. Hence, the current density will accumulate at this part of the topology and this is where wave heating will occur. However, the phenomenon of wave accumulation at a specific place is a feature of both wave types, and illustrates the importance of studying the topology of the corona when considering MHD wave propagation.

  13. Wave variability and wave spectra for wind generated gravity waves 

    E-Print Network [OSTI]

    Bretschneider, Charles L.

    1959-01-01

    A series of experiments of forces on a fixed vertical truncated column due to Stokes 5th order like waves were done in a wave tank. An effort was made to generate the waves as close as possible to theoretical Stokes 5th order waves. A systematic...

  14. Engineering Density of States of Earth Abundant Semiconductors...

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

    of States of Earth Abundant Semiconductors for Enhanced Thermoelectric Power Factor Engineering Density of States of Earth Abundant Semiconductors for Enhanced Thermoelectric...

  15. Weak measurement and Bohmian conditional wave functions

    SciTech Connect (OSTI)

    Norsen, Travis; Struyve, Ward

    2014-11-15

    It was recently pointed out and demonstrated experimentally by Lundeen et al. that the wave function of a particle (more precisely, the wave function possessed by each member of an ensemble of identically-prepared particles) can be “directly measured” using weak measurement. Here it is shown that if this same technique is applied, with appropriate post-selection, to one particle from a perhaps entangled multi-particle system, the result is precisely the so-called “conditional wave function” of Bohmian mechanics. Thus, a plausibly operationalist method for defining the wave function of a quantum mechanical sub-system corresponds to the natural definition of a sub-system wave function which Bohmian mechanics uniquely makes possible. Similarly, a weak-measurement-based procedure for directly measuring a sub-system’s density matrix should yield, under appropriate circumstances, the Bohmian “conditional density matrix” as opposed to the standard reduced density matrix. Experimental arrangements to demonstrate this behavior–and also thereby reveal the non-local dependence of sub-system state functions on distant interventions–are suggested and discussed. - Highlights: • We study a “direct measurement” protocol for wave functions and density matrices. • Weakly measured states of entangled particles correspond to Bohmian conditional states. • Novel method of observing quantum non-locality is proposed.

  16. Funding Opportunity Announcement for Water Power Manufacturing...

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

    for Competitive Marine and Hydrokinetic (MHK) Demonstrations at the Navy's Wave Energy Test Site (WETS) Water Power Program About the Program Research & Development...

  17. Ocean Power (4 Activities) | Department of Energy

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

    our existing non-renewable resources. Ocean power is divided into three categories: wave energy, tidal energy, and ocean thermal energy conversion (OTEC) Systems. It is...

  18. Laboratory Density Functionals

    E-Print Network [OSTI]

    B. G. Giraud

    2007-07-26

    We compare several definitions of the density of a self-bound system, such as a nucleus, in relation with its center-of-mass zero-point motion. A trivial deconvolution relates the internal density to the density defined in the laboratory frame. This result is useful for the practical definition of density functionals.

  19. Power Plant Power Plant

    E-Print Network [OSTI]

    Stillwater Power Plant Wabuska Power Plant Casa Diablo Power Plant Glass Mountain Geothermal Area Lassen Geothermal Area Coso Hot Springs Power Plants Lake City Geothermal Area Thermo Geothermal Area Lakeview Geothermal Area Raft River Geothermal Area Cove Fort Power Plant Roosevelt Power Plant Borax Lake

  20. Nonlinear coupling of left and right handed circularly polarized dispersive Alfvén wave

    SciTech Connect (OSTI)

    Sharma, R. P., E-mail: rpsharma@ces.iitd.ac.in; Sharma, Swati, E-mail: swati.sharma704@gmail.com; Gaur, Nidhi, E-mail: nidhiphysics@gmail.com [Centre for Energy Studies, Indian Institute of Technology Delhi, New Delhi 110016 (India)

    2014-07-15

    The nonlinear phenomena are of prominent interests in understanding the particle acceleration and transportation in the interplanetary space. The ponderomotive nonlinearity causing the filamentation of the parallel propagating circularly polarized dispersive Alfvén wave having a finite frequency may be one of the mechanisms that contribute to the heating of the plasmas. The contribution will be different of the left (L) handed mode, the right (R) handed mode, and the mix mode. The contribution also depends upon the finite frequency of the circularly polarized waves. In the present paper, we have investigated the effect of the nonlinear coupling of the L and R circularly polarized dispersive Alfvén wave on the localized structures formation and the respective power spectra. The dynamical equations are derived in the presence of the ponderomotive nonlinearity of the L and R pumps and then studied semi-analytically as well as numerically. The ponderomotive nonlinearity accounts for the nonlinear coupling between both the modes. In the presence of the adiabatic response of the density fluctuations, the nonlinear dynamical equations satisfy the modified nonlinear Schrödinger equation. The equations thus obtained are solved in solar wind regime to study the coupling effect on localization and the power spectra. The effect of coupling is also studied on Faraday rotation and ellipticity of the wave caused due to the difference in the localization of the left and the right modes with the distance of propagation.

  1. Optimizing Ballast Design of Wave Energy Converters Using Evolutionary Algorithms

    E-Print Network [OSTI]

    Tumer, Kagan

    Optimizing Ballast Design of Wave Energy Converters Using Evolutionary Algorithms Mitch Colby, 97331 kagan.tumer@oregonstate.edu ABSTRACT Wave energy converters promise to be a viable alternative% improvement in power output over a ballast-free wave energy converter. General Terms Algorithms; Applications

  2. Multimodal standing gravity waves: a completely resonant system.

    E-Print Network [OSTI]

    Iooss, Gérard

    Multimodal standing gravity waves: a completely resonant system. G´erard Iooss , Pavel Plotnikov@hydro.nsc.ru Abstract The standing gravity wave problem on an infinitely deep fluid layer is considered under the form be expanded in powers of amplitude is then given up to order 2 . Key words: nonlinear water waves, standing

  3. Correlated noise in networks of gravitational-wave detectors: Subtraction and mitigation

    E-Print Network [OSTI]

    Christensen, Nelson

    of gravitational-wave detectors [22­25] will probe gravitational-wave energy density several orders of magnitude of Technology, Pasadena, California 91125, USA 2 Physics and Astronomy, Carleton College, Northfield, Minnesota

  4. Localization of Classical Waves I: Acoustic Waves.

    E-Print Network [OSTI]

    Localization of Classical Waves I: Acoustic Waves. Alexander Figotin \\Lambda Department, 1997 Abstract We consider classical acoustic waves in a medium described by a position dependent mass the existence of localized waves, i.e., finite energy solutions of the acoustic equations with the property

  5. Coda wave interferometry 1 Coda wave interferometry

    E-Print Network [OSTI]

    Snieder, Roel

    Coda wave interferometry 1 Coda wave interferometry An interferometer is an instrument that is sensitive to the interference of two or more waves (optical or acoustic). For example, an optical interferometer uses two interfering light beams to measure small length changes. Coda wave interferometry

  6. WindWaveFloat Final Report

    SciTech Connect (OSTI)

    Alla Weinstein, Dominique Roddier, Kevin Banister

    2012-03-30

    Principle Power Inc. and National Renewable Energy Lab (NREL) have completed a contract to assess the technical and economic feasibility of integrating wave energy converters into the WindFloat, resulting in a new concept called the WindWaveFloat (WWF). The concentration of several devices on one platform could offer a potential for both economic and operational advantages. Wind and wave energy converters can share the electrical cable and power transfer equipment to transport the electricity to shore. Access to multiple generation devices could be simplified, resulting in cost saving at the operational level. Overall capital costs may also be reduced, provided that the design of the foundation can be adapted to multiple devices with minimum modifications. Finally, the WindWaveFloat confers the ability to increase energy production from individual floating support structures, potentially leading to a reduction in levelized energy costs, an increase in the overall capacity factor, and greater stability of the electrical power delivered to the grid. The research conducted under this grant investigated the integration of several wave energy device types into the WindFloat platform. Several of the resulting system designs demonstrated technical feasibility, but the size and design constraints of the wave energy converters (technical and economic) make the WindWaveFloat concept economically unfeasible at this time. Not enough additional generation could be produced to make the additional expense associated with wave energy conversion integration into the WindFloat worthwhile.

  7. Effect of Impurities Scattering Potential on NMR relaxation rate in impure d-wave superconductors

    E-Print Network [OSTI]

    P. Udomsamuthirun; K. Meemon

    2009-07-20

    The purpose of our research is to study the nuclear spin lattice relaxation rate of impure d-wave superconductors. We use the Green function method to derive the approximation equation of density of states including the impurity scattering potential. We can get the analytic equation of the nuclear spin lattice relaxation rate that contained the impurity scattering potential in case of weak scattering potential and strong scattering potential in the simple form as the power series of order parameter and temperature . The numerical calculations show that there is coherence peak in the weak impurity scattering potential but there is no peak in the strong impurity scattering potential.

  8. Seasonal and diurnal dependence of Pc 3-5 magnetic pulsation power at geomagnetically conjugate stations in the auroral zones

    SciTech Connect (OSTI)

    Saito, Hiroaki (Univ. of Electro-Communications, Tokyo (Japan) National Institute of Polar Research, Tokyo (Japan)); Sato, Natsuo (National Institute of Polar Research, Tokyo (Japan)); Tonegawa, Yutaka (Tokai Univ., Hiratsuka (Japan)); Yoshino, Takeo (Univ. of Electro-Communications, Tokyo (Japan)); Saemundsson, T. (Univ. of Iceland, Reykjavik (Iceland))

    1989-06-01

    Seasonal and diurnal variations of Pc 3-5 magnetic pulsation powers have been examined using 2 years of magnetic data from geomagnetically conjugate stations, Syowa in Antarctica and Husafell and Tjoernes in Iceland. The magnetic pulsation powers are found to be relatively higher at the winter hemisphere station than at the summer station. The pulsations observed during equinox show a diurnal dependence, i.e., that the power density is higher in the geomagnetic morning at the stations in Iceland than at Syowa, and this relationship is reversed in the afternoon. The power density ratio of Pc 3 pulsations between the conjugate stations, which is associated with the seasons and with local time, is higher than that of Pc 5. These characteristics can be attributed to the effects of sunlight in the ionosphere, i.e., Pc 3-5 pulsations are shielded when the waves propagate from the magnetosphere to the ground through the sunlit ionosphere.

  9. Measurements of plasma bremsstrahlung and plasma energy density produced by electron cyclotron resonance ion source plasmas

    E-Print Network [OSTI]

    Noland, Jonathan David

    2011-01-01

    of x-ray power and plasma energy density with microwaveof diamagnetic loop used for plasma energy density mea-the average electron energy and density. During the slowly

  10. Mass dependence of the vacuum energy density in the massive Schwinger model

    E-Print Network [OSTI]

    Taekoon Lee

    2007-03-09

    The vacuum energy density of the massive Schwinger model is shown to be not power expandable in the fermion mass.

  11. Turbulent density fluctuations in the solar wind

    E-Print Network [OSTI]

    Ingale, Madhusudan

    2015-01-01

    Treatments of the radio scattering due to density turbulence in the solar wind typically employ asymptotic approximations to the phase structure function. We use a general structure function (GSF) that straddles the asymptotic limits and quantify the relative error introduced by the approximations. We show that the regimes where GSF predictions are accurate than those of its asymptotic approximations is not only of practical relevance, but are where inner scale effects influence the estimate of the scatter-broadening. Thus we propose that GSF should henceforth be used for scatter broadening calculations and estimates of quantities characterizing density turbulence in the solar corona and solar wind. In the next part of this thesis we use measurements of density turbulence in the solar wind from previously publish observations of radio wave scattering and interplanetary scintillations. Density fluctuations are inferred using the GSF for radio scattering data and existing analysis methods for IPS. Assuming that...

  12. Refrigeration system having standing wave compressor

    DOE Patents [OSTI]

    Lucas, Timothy S. (Glen Allen, VA)

    1992-01-01

    A compression-evaporation refrigeration system, wherein gaseous compression of the refrigerant is provided by a standing wave compressor. The standing wave compressor is modified so as to provide a separate subcooling system for the refrigerant, so that efficiency losses due to flashing are reduced. Subcooling occurs when heat exchange is provided between the refrigerant and a heat pumping surface, which is exposed to the standing acoustic wave within the standing wave compressor. A variable capacity and variable discharge pressure for the standing wave compressor is provided. A control circuit simultaneously varies the capacity and discharge pressure in response to changing operating conditions, thereby maintaining the minimum discharge pressure needed for condensation to occur at any time. Thus, the power consumption of the standing wave compressor is reduced and system efficiency is improved.

  13. Parametric internal waves in a compressible fluid

    E-Print Network [OSTI]

    Das, Kausik S; Bhattacharyay, A

    2007-01-01

    We describe the effect of vibration on a confined volume of fluid which is density stratified due to its compressibility. We show that internal gravity-acoustic waves can be parametrically destabilized by the vibration. The resulting instability is similar to the classic Faraday instability of surface waves, albeit modified by the compressible nature of the fluid. It may be possible to observe experimentally near a gas-liquid critical point.

  14. Shock wave propagation in vibrofluidized granular materials

    E-Print Network [OSTI]

    Kai Huang; Guoqing Miao; Peng Zhang; Yi Yun; Rongjue Wei

    2005-11-29

    Shock wave formation and propagation in two-dimensional granular materials under vertical vibration are studied by digital high speed photography. The steepen density and temperature wave fronts form near the plate as granular layer collides with vibrating plate and propagate upward through the layer. The temperature front is always in the transition region between the upward and downward granular flows. The effects of driving parameters and particle number on the shock are also explored.

  15. High Energy Density Microwaves

    SciTech Connect (OSTI)

    Phillips, R.M. [Stanford Linear Accelerator Center, Stanford, CA 94309 (United States)

    1999-04-01

    These proceedings represent papers presented at the RF98 Workshop entitled `High Energy Density Microwaves` held in California in October, 1998. The topics discussed were predominantly accelerator{minus}related. The Workshop dealt, for the most part, with the generation and control of electron beams, the amplification of RF signals, the design of mode converters, and the effect of very high RF field gradients. This Workshop was designed to address the concerns of the microwave tube industry worldwide, the plasma physicists who deal with very high beam currents and gigawatts of RF power, and researchers in accelerator centers around the world. Papers were presented on multibeam klystrons, gyrotron development, plasmas in microwave tubes, RF breakdown, and alternatives to conventional linear coliders at 1 TeV and above. The Workshop was partially sponsored by the US Department of Energy. There were 46 papers presented at the conference,out of which 19 have been abstracted for the Energy,Science and Technology database.(AIP)

  16. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. 60, NO. 7, JULY 2012 2277 Low-Power Wireless Power Delivery

    E-Print Network [OSTI]

    Popovic, Zoya

    of incident power levels are RF identifications (RFIDs) and power beaming. In RFIDs, an interrogating RF wave transmits a plane wave incident on a rectenna element or array (RF power re- ceiver). Following the potential for maintenance-free operation. This paper focuses on a methodology for designing low-power

  17. Counting energy packets in the electromagnetic wave

    E-Print Network [OSTI]

    Stefan Popescu; Bernhard Rothenstein

    2007-05-18

    We discuss the concept of energy packets in respect to the energy transported by electromagnetic waves and we demonstrate that this physical quantity can be used in physical problems involving relativistic effects. This refined concept provides results compatible to those obtained by simpler definition of energy density when relativistic effects apply to the free electromagnetic waves. We found this concept further compatible to quantum theory perceptions and we show how it could be used to conciliate between different physical approaches including the classical electromagnetic wave theory, the special relativity and the quantum theories.

  18. Phases of holographic d-wave superconductor

    E-Print Network [OSTI]

    Krikun, Alexander

    2015-01-01

    We study different phases in the holographic model of d-wave superconductor. These are described by solutions to the classical equations of motion found in different ansatze. Apart from the known homogeneous d-wave superconducting phase we find three new solutions. Two of them represent two distinct families of the spatially modulated solutions, which realize the charge density wave phases in the dual theory. The third one is the new homogeneous phase with nonzero anapole moment. These phases are relevant to the physics of cuprate high-Tc superconductor in pseudogap region. While the d-wave phase preserves translation, parity and time reversal symmetry, the striped phases break translations spontaneously. Parity and time-reversal are preserved when combined with discrete half-periodic shift of the wave. In anapole phase translation symmetry is preserved, but parity and time reversal are spontaneously broken. All of the considered solutions brake the global $U(1)$. Thermodynamical treatment shows that in the s...

  19. Langlee Wave Power AS | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History View NewTexas:Montezuma, Arizona: Energy Resources JumpColorado:New

  20. Wave Power Plant Inc | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION JEnvironmental Jump to:EA EISTJThinWarsaw, Poland:Energy InformationWausau High SchoolInc Jump

  1. Kinetic Wave Power | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIXsource History View NewGuam:onItronKanoshKetchikan Public UtilitiesKiloa metamorphic

  2. Wave Energy Basics

    Broader source: Energy.gov [DOE]

    Wave energy technologies extract energy directly from surface waves or from pressure fluctuations below the surface. Renewable energy analysts believe there is enough energy in ocean waves to provide up to 2 terawatts of electricity.

  3. Wave Control Introduction

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    focussing: in crossing seas due to coastal or submarine convergences. Moreover, (rogue) wave energy devices maker to create the highest rogue wave? geometry and dynamo in a new rogue wave energy device? maximum

  4. Capillary wave turbulence on a spherical fluid surface in low gravity

    E-Print Network [OSTI]

    Falcon, Eric

    .epljournal.org #12;Europhysics Letters (EPL) has a new online home at www.epljournal.org Take a look for the latest. The surface wave amplitude displays power law spectrum over two decades in frequency, corresponding´en waves in solar wind [3], plasmas [4], surface waves on elastic plates [5], and spin waves in solids

  5. Capillary-Gravity Waves Generated by a Slow Moving Object A. D. Chepelianskii,1,2

    E-Print Network [OSTI]

    Raphael, Elie

    Capillary-Gravity Waves Generated by a Slow Moving Object A. D. Chepelianskii,1,2 F. Chevy,3 and E=2 . The dispersive nature of capillary-gravity waves is responsible for the complicated wave pattern generated) or an external pressure source [2­6]. Since the disturbance expends a power to generate these waves

  6. UTILITY OF EXTRACTING CY PARTICLE ENERGY BY WAVES N.J. FISCH, M.C. HERRMANN

    E-Print Network [OSTI]

    UTILITY OF EXTRACTING CY PARTICLE ENERGY BY WAVES N.J. FISCH, M.C. HERRMANN Princeton Plasma by injecting waves that diffuse the a particles both in space and in energy, rather than just in energy [13 particle power by waves, and that these waves might then damp resonantly on the fast energy tail

  7. Structural power flow measurement

    SciTech Connect (OSTI)

    Falter, K.J.; Keltie, R.F.

    1988-12-01

    Previous investigations of structural power flow through beam-like structures resulted in some unexplained anomalies in the calculated data. In order to develop structural power flow measurement as a viable technique for machine tool design, the causes of these anomalies needed to be found. Once found, techniques for eliminating the errors could be developed. Error sources were found in the experimental apparatus itself as well as in the instrumentation. Although flexural waves are the carriers of power in the experimental apparatus, at some frequencies longitudinal waves were excited which were picked up by the accelerometers and altered power measurements. Errors were found in the phase and gain response of the sensors and amplifiers used for measurement. A transfer function correction technique was employed to compensate for these instrumentation errors.

  8. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    2015-01-01

    wave generation by convection in water Michael Le Bars 1,2 ,investigate the dynamics of water cooled from below at 0 ° Cof the unusual property that water’s density maximum is at

  9. Shear-wave splitting and reservoir crack characterization: the...

    Open Energy Info (EERE)

    of its geothermal potential and day-to-day production. To detect the geometry and density of fracture systems we applied the shear-wave splitting technique to a large number...

  10. Internal wave energy radiated from a turbulent mixed layer

    SciTech Connect (OSTI)

    Munroe, James R.; Sutherland, Bruce R.

    2014-09-15

    We examine mixed-layer deepening and the generation of internal waves in stratified fluid resulting from turbulence that develops in response to an applied surface stress. In laboratory experiments the stress is applied over the breadth of a finite-length tank by a moving roughened conveyor belt. The turbulence in the shear layer is characterized using particle image velocimetry to measure the kinetic energy density. The internal waves are measured using synthetic schlieren to determine their amplitudes, frequencies, and energy density. We also perform fully nonlinear numerical simulations restricted to two dimensions but in a horizontally periodic domain. These clearly demonstrate that internal waves are generated by transient eddies at the integral length scale of turbulence and which translate with the background shear along the base of the mixed layer. In both experiments and simulations we find that the energy density of the generated waves is 1%–3% of the turbulent kinetic energy density of the turbulent layer.

  11. A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma

    SciTech Connect (OSTI)

    Yang Min; Li Xiaoping; Xie Kai; Liu Donglin; Liu Yanming

    2013-01-15

    A large volume uniform plasma generator is proposed for the experiments of electromagnetic (EM) wave propagation in plasma, to reproduce a 'black out' phenomenon with long duration in an environment of the ordinary laboratory. The plasma generator achieves a controllable approximate uniform plasma in volume of 260 mm Multiplication-Sign 260 mm Multiplication-Sign 180 mm without the magnetic confinement. The plasma is produced by the glow discharge, and the special discharge structure is built to bring a steady approximate uniform plasma environment in the electromagnetic wave propagation path without any other barriers. In addition, the electron density and luminosity distributions of plasma under different discharge conditions were diagnosed and experimentally investigated. Both the electron density and the plasma uniformity are directly proportional to the input power and in roughly reverse proportion to the gas pressure in the chamber. Furthermore, the experiments of electromagnetic wave propagation in plasma are conducted in this plasma generator. Blackout phenomena at GPS signal are observed under this system and the measured attenuation curve is of reasonable agreement with the theoretical one, which suggests the effectiveness of the proposed method.

  12. Geometrical vs wave optics under gravitational waves

    E-Print Network [OSTI]

    Raymond Angélil; Prasenjit Saha

    2015-05-20

    We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely null geodesics and Maxwell's equations, or, geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics - rather than solving Maxwell's equations directly for the fields, as in most previous approaches - we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic fields all experience the same phase modulation. Applying such a phase modulation to a superposition of plane waves corresponding to a Gaussian wave packet leads to time delays.

  13. Pelamis Wave Power Ocean Power Delivery Ltd | 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 on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to:Newberg,Energy LLC Jump to:3 ofAltos delValley El PwrPeking

  14. Subduction factory 1. Theoretical mineralogy, densities, seismic wave speeds,

    E-Print Network [OSTI]

    Hacker, Bradley R.

    Bradley R. Hacker Department of Geological Sciences, University of California, Santa Barbara, California physics, H2O Citation: Hacker, B. R., G. A. Abers, and S. M. Peacock, Subduction factory, 1, Theoretical a consistent model; the com- panion paper [Hacker et al., 2003], on the relationship between intermediate

  15. Using Radio Waves to Control Fusion Plasma Density

    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: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 - 19PortalStatusUserUserHomeUsing RunningUsing

  16. Neutral depletion and the helicon density limit

    SciTech Connect (OSTI)

    Magee, R. M.; Galante, M. E.; Carr, J. Jr.; Lusk, G.; McCarren, D. W.; Scime, E. E.

    2013-12-15

    It is straightforward to create fully ionized plasmas with modest rf power in a helicon. It is difficult, however, to create plasmas with density >10{sup 20} m{sup ?3}, because neutral depletion leads to a lack of fuel. In order to address this density limit, we present fast (1 MHz), time-resolved measurements of the neutral density at and downstream from the rf antenna in krypton helicon plasmas. At the start of the discharge, the neutral density underneath the antenna is reduced to 1% of its initial value in 15 ?s. The ionization rate inferred from these data implies that the electron temperature near the antenna is much higher than the electron temperature measured downstream. Neutral density measurements made downstream from the antenna show much slower depletion, requiring 14 ms to decrease by a factor of 1/e. Furthermore, the downstream depletion appears to be due to neutral pumping rather than ionization.

  17. Evolution of gravitational waves through the cosmological QCD transition

    E-Print Network [OSTI]

    Dominik J. Schwarz

    1998-11-06

    The spectrum of gravitational waves that have been produced in inflation is modified during cosmological transitions. Large drops in the number of relativistic particles, like during the QCD transition or at $e^+e^-$ annihilation, lead to steps in the spectrum of gravitational waves. We calculate the transfer function for the differential energy density of gravitational waves for a first-order and for a crossover QCD transition.

  18. Relic gravitational waves and the generalized second law

    E-Print Network [OSTI]

    German Izquierdo; Diego Pavon

    2005-01-12

    The generalized second law of gravitational thermodynamics is applied to the present era of accelerated expansion of the Universe. In spite of the fact that the entropy of matter and relic gravitational waves inside the event horizon diminish, the mentioned law is fulfilled provided that the expression for the entropy density of the gravitational waves satisfies a certain condition.

  19. Effects of Phase Transition induced density fluctuations on pulsar dynamics

    E-Print Network [OSTI]

    Bagchi, Partha; Layek, Biswanath; Srivastava, Ajit M

    2015-01-01

    We show that density fluctuations during phase transitions in pulsar cores may have non-trivial effects on pulsar timings, and may also possibly account for glitches and anti-glitches. These density fluctuations invariably lead to non-zero off-diagonal components of the moment of inertia, leading to transient wobbling of star. Thus, accurate measurements of pulsar timing and intensity modulations (from wobbling) may be used to identify the specific pattern of density fluctuations, hence the particular phase transition, occurring inside the pulsar core. Changes in quadrupole moment from rapidly evolving density fluctuations during the transition, with very short time scales, may provide a new source for gravitational waves.

  20. Volcanoes generate devastating waves

    SciTech Connect (OSTI)

    Lockridge, P. (National Geophysical Data Center, Boulder, CO (USA))

    1988-01-01

    Although volcanic eruptions can cause many frightening phenomena, it is often the power of the sea that causes many volcano-related deaths. This destruction comes from tsunamis (huge volcano-generated waves). Roughly one-fourth of the deaths occurring during volcanic eruptions have been the result of tsunamis. Moreover, a tsunami can transmit the volcano's energy to areas well outside the reach of the eruption itself. Some historic records are reviewed. Refined historical data are increasingly useful in predicting future events. The U.S. National Geophysical Data Center/World Data Center A for Solid Earth Geophysics has developed data bases to further tsunami research. These sets of data include marigrams (tide gage records), a wave-damage slide set, digital source data, descriptive material, and a tsunami wall map. A digital file contains information on methods of tsunami generation, location, and magnitude of generating earthquakes, tsunami size, event validity, and references. The data can be used to describe areas mot likely to generate tsunamis and the locations along shores that experience amplified effects from tsunamis.

  1. Visualization of electronic density

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

    Grosso, Bastien; Cooper, Valentino R.; Pine, Polina; Hashibon, Adham; Yaish, Yuval; Adler, Joan

    2015-04-22

    An atom’s volume depends on its electronic density. Although this density can only be evaluated exactly for hydrogen-like atoms, there are many excellent numerical algorithms and packages to calculate it for other materials. 3D visualization of charge density is challenging, especially when several molecular/atomic levels are intertwined in space. We explore several approaches to 3D charge density visualization, including the extension of an anaglyphic stereo visualization application based on the AViz package to larger structures such as nanotubes. We will describe motivations and potential applications of these tools for answering interesting questions about nanotube properties.

  2. Relativistic electron acceleration by oblique whistler waves

    SciTech Connect (OSTI)

    Yoon, Peter H.; School of Space Research, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 ; Pandey, Vinay S.; Lee, Dong-Hun

    2013-11-15

    Test-particle simulations of electrons interacting with finite-amplitude, obliquely propagating whistler waves are carried out in order to investigate the acceleration of relativistic electrons by these waves. According to the present findings, an efficient acceleration of relativistic electrons requires a narrow range of oblique propagation angles, close to the whistler resonance cone angle, when the wave amplitude is held constant at relatively low value. For a constant wave propagation angle, it is found that a range of oblique whistler wave amplitudes permits the acceleration of relativistic electrons to O(MeV) energies. An initial distribution of test electrons is shown to form a power-law distribution when plotted in energy space. It is also found that the acceleration is largely uniform in electron pitch-angle space.

  3. Understanding ion cyclotron harmonic fast wave heating losses in the scrape off layer of tokamak plasmas

    SciTech Connect (OSTI)

    Bertelli, N [PPPL; Jaeger, E F; Hosea, J C; Phillips, C K; Berry, L; Bonoli, P T; Gerhardt, S P [PPPL; Green, D; LeBlanc, B [PPPL; Perkins, R J; Ryan, P M; Taylor, G; Valeo, E J; Wilso, J R; Wright, J C

    2014-07-01

    Fast waves at harmonics of the ion cyclotron frequency, which have been used successfully on National Spherical Torus Experiment (NSTX), will also play an important role in ITER and are a promising candidate for the Fusion Nuclear Science Facility (FNSF) designs based on spherical torus (ST). Experimental studies of high harmonic fast waves (HHFW) heating on the NSTX have demonstrated that substantial HHFW power loss occurs along the open field lines in the scrape-off layer (SOL), but the mechanism behind the loss is not yet understood. The full wave RF code AORSA, in which the edge plasma beyond the last closed flux surface (LCFS) is included in the solution domain, is applied to specific NSTX discharges in order to predict the effects and possible causes of this power loss. In the studies discussed here, a collisional damping parameter has been implemented in AORSA as a proxy to represent the real, and most likely nonlinear, damping processes. A prediction for the NSTX Upgrade (NSTX-U) experiment, that will begin operation next year, is also presented, indicating a favorable condition for the experiment due to a wider evanescent region in edge density.*Research supported by the U.S. DOE under Contract No. DE-AC02-09CH11466 with Princeton University.

  4. Quantification of the influence of directional sea state parameters over the performances of wave energy converters 

    E-Print Network [OSTI]

    Pascal, Remy Claude Rene

    2012-11-29

    Accurate predictions of the annual energy yield from wave energy converters are essential to the development of the wave industry. The current method based on power matrices uses only a small part of the data available ...

  5. Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean...

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

    Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current, and In-Stream Hydrokinetic Power Assessment of Projected Life-Cycle Costs for Wave, Tidal, Ocean Current,...

  6. Big Flippin' Wave Science

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Verdes, Campus Point, Coal Oil Point (Sands) Waves propagate perpendicular to isobaths (lines of constant

  7. Water Waves Roger Grimshaw

    E-Print Network [OSTI]

    Water Waves Roger Grimshaw May 7, 2003 Abstract A short review of the theory of weakly nonlinear water waves, prepared for the forthcoming Encyclopedia of Nonlinear Science 1 Introduction Water waves nonlinear waves. Throughout the theory is based on the traditional assumptions that water is inviscid

  8. Effects of a random spatial variation of the plasma density on the mode conversion in cold, unmagnetized, and stratified plasmas

    SciTech Connect (OSTI)

    Jung Yu, Dae; Kim, Kihong

    2013-12-15

    We study the effects of a random spatial variation of the plasma density on the mode conversion of electromagnetic waves into electrostatic oscillations in cold, unmagnetized, and stratified plasmas. Using the invariant imbedding method, we calculate precisely the electromagnetic field distribution and the mode conversion coefficient, which is defined to be the fraction of the incident wave power converted into electrostatic oscillations, for the configuration where a numerically generated random density variation is added to the background linear density profile. We repeat similar calculations for a large number of random configurations and take an average of the results. We obtain a peculiar nonmonotonic dependence of the mode conversion coefficient on the strength of randomness. As the disorder increases from zero, the maximum value of the mode conversion coefficient decreases initially, then increases to a maximum, and finally decreases towards zero. The range of the incident angle in which mode conversion occurs increases monotonically as the disorder increases. We present numerical results suggesting that the decrease of mode conversion mainly results from the increased reflection due to the Anderson localization effect originating from disorder, whereas the increase of mode conversion of the intermediate disorder regime comes from the appearance of many resonance points and the enhanced tunneling between the resonance points and the cutoff point. We also find a very large local enhancement of the magnetic field intensity for particular random configurations. In order to obtain high mode conversion efficiency, it is desirable to restrict the randomness close to the resonance region.

  9. Applying the cold plasma dispersion relation to whistler mode chorus waves: EMFISIS wave measurements from the Van Allen Probes

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

    Hartley, D. P.; Chen, Y.; Kletzing, C. A.; Denton, M. H.; Kurth, W. S.

    2015-02-17

    Most theoretical wave models require the power in the wave magnetic field in order to determine the effect of chorus waves on radiation belt electrons. However, researchers typically use the cold plasma dispersion relation to approximate the magnetic wave power when only electric field data are available. In this study, the validity of using the cold plasma dispersion relation in this context is tested using Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) observations of both the electric and magnetic spectral intensities in the chorus wave band (0.1–0.9 fce). Results from this study indicate that the calculated wavemore »intensity is least accurate during periods of enhanced wave activity. For observed wave intensities >10?³ nT², using the cold plasma dispersion relation results in an underestimate of the wave intensity by a factor of 2 or greater 56% of the time over the full chorus wave band, 60% of the time for lower band chorus, and 59% of the time for upper band chorus. Hence, during active periods, empirical chorus wave models that are reliant on the cold plasma dispersion relation will underestimate chorus wave intensities to a significant degree, thus causing questionable calculation of wave-particle resonance effects on MeV electrons.« less

  10. Study of the ceramic window geometry for HWR and Spoke cavity power coupler

    E-Print Network [OSTI]

    Mielot, C

    This document describes all the detailed comparison of several ceramic window design for fundamental power coupler meant to provide RF power to spoke or half wave superconducting cavities.

  11. Ocean Power Technologies (TRL 5 6 System) - PB500, 500 kW Utility...

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

    technologiesinchart.ppt More Documents & Publications Advanced, High Power, Next Scale, Wave Energy Conversion Device Ocean Power Technologies (TRL 7 8 System) - Reedsport PB150...

  12. Accurately specifying storm-time ULF wave radial diffusion in the radiation belts

    E-Print Network [OSTI]

    Dimitrakoudis, Stavros; Balasis, Georgios; Papadimitriou, Constantinos; Anastasiadis, Anastasios; Daglis, Ioannis A

    2015-01-01

    Ultra-low frequency (ULF) waves can contribute to the transport, acceleration and loss of electrons in the radiation belts through inward and outward diffusion. However, the most appropriate parameters to use to specify the ULF wave diffusion rates are unknown. Empirical representations of diffusion coefficients often use Kp; however, specifications using ULF wave power offer an improved physics-based approach. We use 11 years of ground-based magnetometer array measurements to statistically parameterise the ULF wave power with Kp, solar wind speed, solar wind dynamic pressure and Dst. We find Kp is the best single parameter to specify the statistical ULF wave power driving radial diffusion. Significantly, remarkable high energy tails exist in the ULF wave power distributions when expressed as a function of Dst. Two parameter ULF wave power specifications using Dst as well as Kp provide a better statistical representation of storm-time radial diffusion than any single variable alone.

  13. Density-dependent covariant energy density functionals

    SciTech Connect (OSTI)

    Lalazissis, G. A.

    2012-10-20

    Relativistic nuclear energy density functionals are applied to the description of a variety of nuclear structure phenomena at and away fromstability line. Isoscalar monopole, isovector dipole and isoscalar quadrupole giant resonances are calculated using fully self-consistent relativistic quasiparticle randomphase approximation, based on the relativistic Hartree-Bogoliubovmodel. The impact of pairing correlations on the fission barriers in heavy and superheavy nuclei is examined. The role of pion in constructing desnity functionals is also investigated.

  14. Low density molded desiccant

    SciTech Connect (OSTI)

    Lula, J.W.

    1982-01-01

    A formulation for low density syntactic foam desiccant, using a polyimide resin binder, glass microbubble filler, and molecular sieve desiccant powder has been developed. The formulation may be modified easily to meet specific part requirements such as density and desired moisture pickup. Some parts can be molded to size.

  15. Electron scattering and nonlinear trapping by oblique whistler waves: The critical wave intensity for nonlinear effects

    SciTech Connect (OSTI)

    Artemyev, A. V. Vasiliev, A. A.; Mourenas, D.; Krasnoselskikh, V. V.

    2014-10-15

    In this paper, we consider high-energy electron scattering and nonlinear trapping by oblique whistler waves via the Landau resonance. We use recent spacecraft observations in the radiation belts to construct the whistler wave model. The main purpose of the paper is to provide an estimate of the critical wave amplitude for which the nonlinear wave-particle resonant interaction becomes more important than particle scattering. To this aim, we derive an analytical expression describing the particle scattering by large amplitude whistler waves and compare the corresponding effect with the nonlinear particle acceleration due to trapping. The latter is much more rare but the corresponding change of energy is substantially larger than energy jumps due to scattering. We show that for reasonable wave amplitudes ?10–100?mV/m of strong whistlers, the nonlinear effects are more important than the linear and nonlinear scattering for electrons with energies ?10–50?keV. We test the dependencies of the critical wave amplitude on system parameters (background plasma density, wave frequency, etc.). We discuss the role of obtained results for the theoretical description of the nonlinear wave amplification in radiation belts.

  16. Sensitivity Achieved by the LIGO and Virgo Gravitational Wave Detectors during LIGO's Sixth and Virgo's Second and Third Science Runs

    E-Print Network [OSTI]

    The LIGO Scientific Collaboration; The Virgo Collaboration

    2012-03-15

    We summarize the sensitivity achieved by the LIGO and Virgo gravitational wave detectors for low-mass compact binary coalescence (CBC) searches during LIGO's sixth science run and Virgo's second and third science runs. We present strain noise power spectral densities (PSDs) which are representative of the typical performance achieved by the detectors in these science runs. The data presented here and in the accompanying web-accessible data files are intended to be released to the public as a summary of detector performance for low-mass CBC searches during S6 and VSR2-3.

  17. Spatial damping of propagating sausage waves in coronal cylinders

    E-Print Network [OSTI]

    Guo, Ming-Zhe; Li, Bo; Xia, Li-Dong; Yu, Hui

    2015-01-01

    Sausage modes are important in coronal seismology. Spatially damped propagating sausage waves were recently observed in the solar atmosphere. We examine how wave leakage influences the spatial damping of sausage waves propagating along coronal structures modeled by a cylindrical density enhancement embedded in a uniform magnetic field. Working in the framework of cold magnetohydrodynamics, we solve the dispersion relation (DR) governing sausage waves for complex-valued longitudinal wavenumber $k$ at given real angular frequencies $\\omega$. For validation purposes, we also provide analytical approximations to the DR in the low-frequency limit and in the vicinity of $\\omega_{\\rm c}$, the critical angular frequency separating trapped from leaky waves. In contrast to the standing case, propagating sausage waves are allowed for $\\omega$ much lower than $\\omega_{\\rm c}$. However, while able to direct their energy upwards, these low-frequency waves are subject to substantial spatial attenuation. The spatial damping ...

  18. Shock-activated electrochemical power supplies

    DOE Patents [OSTI]

    Benedick, W.B.; Graham, R.A.; Morosin, B.

    1987-04-20

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolyte rendering the electrolyte electrochemically active. 2 figs.

  19. Shock-activated electrochemical power supplies

    DOE Patents [OSTI]

    Benedick, W.B.; Graham, R.A.; Morosin, B.

    1988-11-08

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolytes rendering the electrolyte electrochemically active. 2 figs.

  20. Shock-activated electrochemical power supplies

    DOE Patents [OSTI]

    Benedick, William B. (Albuquerque, NM); Graham, Robert A. (Los Lunas, NM); Morosin, Bruno (Albuquerque, NM)

    1988-01-01

    A shock-activated electrochemical power supply is provided which is initiated extremely rapidly and which has a long shelf life. Electrochemical power supplies of this invention are initiated much faster than conventional thermal batteries. Power supplies of this invention comprise an inactive electrolyte and means for generating a high-pressure shock wave such that the shock wave is propagated through the electrolytes rendering the electrolyte electrochemically active.

  1. Shock-Wave Attenuation and Energy-Dissipation Potential of Granular Materials

    E-Print Network [OSTI]

    Grujicic, Mica

    Shock-Wave Attenuation and Energy-Dissipation Potential of Granular Materials Mica Grujicic, B this approach, both compression shocks and decompression waves are treated as (stress, specific volume, particle velocity, mass-based internal energy density, temperature, and mass-based entropy density) propagating

  2. Stochastic acceleration of electrons by fast magnetosonic waves in solar flares: the effects of anisotropy in velocity and wavenumber space

    SciTech Connect (OSTI)

    Pongkitiwanichakul, Peera; Chandran, Benjamin D. G.

    2014-11-20

    We develop a model for stochastic acceleration of electrons in solar flares. As in several previous models, the electrons are accelerated by turbulent fast magnetosonic waves ({sup f}ast waves{sup )} via transit-time-damping (TTD) interactions. (In TTD interactions, fast waves act like moving magnetic mirrors that push the electrons parallel or anti-parallel to the magnetic field). We also include the effects of Coulomb collisions and the waves' parallel electric fields. Unlike previous models, our model is two-dimensional in both momentum space and wavenumber space and takes into account the anisotropy of the wave power spectrum F{sub k} and electron distribution function f {sub e}. We use weak turbulence theory and quasilinear theory to obtain a set of equations that describes the coupled evolution of F{sub k} and f {sub e}. We solve these equations numerically and find that the electron distribution function develops a power-law-like non-thermal tail within a restricted range of energies E in (E {sub nt}, E {sub max}). We obtain approximate analytic expressions for E {sub nt} and E {sub max}, which describe how these minimum and maximum energies depend upon parameters such as the electron number density and the rate at which fast-wave energy is injected into the acceleration region at large scales. We contrast our results with previous studies that assume that F{sub k} and f {sub e} are isotropic, and we compare one of our numerical calculations with the time-dependent hard-X-ray spectrum observed during the 1980 June 27 flare. In our numerical calculations, the electron energy spectra are softer (steeper) than in models with isotropic F{sub k} and f {sub e} and closer to the values inferred from observations of solar flares.

  3. Stable operating regime for traveling wave devices

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    2000-01-01

    Autophase stability is provided for a traveling wave device (TWD) electron beam for amplifying an RF electromagnetic wave in walls defining a waveguide for said electromagnetic wave. An off-axis electron beam is generated at a selected energy and has an energy noise inherently arising from electron gun. The off-axis electron beam is introduced into the waveguide. The off-axis electron beam is introduced into the waveguide at a second radius. The waveguide structure is designed to obtain a selected detuning of the electron beam. The off-axis electron beam has a velocity and the second radius to place the electron beam at a selected distance from the walls defining the waveguide, wherein changes in a density of the electron beam due to the RF electromagnetic wave are independent of the energy of the electron beam to provide a concomitant stable operating regime relative to the energy noise.

  4. Fast wave evanescence in filamentary boundary plasmas

    SciTech Connect (OSTI)

    Myra, J. R. [Lodestar Research Corporation, Boulder, Colorado 80027 (United States)] [Lodestar Research Corporation, Boulder, Colorado 80027 (United States)

    2014-02-15

    Radio frequency waves for heating and current drive of plasmas in tokamaks and other magnetic confinement devices must first traverse the scrape-off-layer (SOL) before they can be put to their intended use. The SOL plasma is strongly turbulent and intermittent in space and time. These turbulent properties of the SOL, which are not routinely taken into account in wave propagation codes, can have an important effect on the coupling of waves through an evanescent SOL or edge plasma region. The effective scale length for fast wave (FW) evanescence in the presence of short-scale field-aligned filamentary plasma turbulence is addressed in this paper. It is shown that although the FW wavelength or evanescent scale length is long compared with the dimensions of the turbulence, the FW does not simply average over the turbulent density; rather, the average is over the exponentiation rate. Implications for practical situations are discussed.

  5. Creating and studying ion acoustic waves in ultracold neutral plasmasa) T. C. Killian,1,b)

    E-Print Network [OSTI]

    California at San Diego, University of

    Creating and studying ion acoustic waves in ultracold neutral plasmasa) T. C. Killian,1,b) P. Mc online 23 March 2012) We excite ion acoustic waves in ultracold neutral plasmas by imprinting density of IAWs in UNPs, including the effects of strong coupling, was published16 and ion-acoustic shock waves

  6. An explicit time evolution method for acoustic wave propagation Huafeng Liu1

    E-Print Network [OSTI]

    Niu, Fenglin

    . We started from the constant-density acoustic wave equation and obtained an analytical timeAn explicit time evolution method for acoustic wave propagation Huafeng Liu1 , Nanxun Dai2 (ETE) method to efficiently simulate wave propaga- tion in acoustic media with high temporal accuracy

  7. Homogenization in random media and effective medium theory for high frequency waves

    E-Print Network [OSTI]

    Bal, Guillaume

    Homogenization in random media and effective medium theory for high frequency waves Guillaume Bal May 1, 2007 Abstract We consider the homogenization of the wave equation with high frequency initial density of high frequency waves propagating in highly heterogeneous media when the wavelength is much

  8. Non-Reflecting Internal Wave Beam Propagation in the Deep Ocean Roger Grimshaw1)

    E-Print Network [OSTI]

    ). Here we analyze theoretically the penetration of internal waves in an ocean with continuousNon-Reflecting Internal Wave Beam Propagation in the Deep Ocean Roger Grimshaw1) , Efim Pelinovsky1 2008 Using linear internal wave theory for an ocean stratified by both density and current, we identify

  9. Title of Document: LONGITUDINAL SPACE-CHARGE WAVES INDUCED BY ENERGY MODULATIONS

    E-Print Network [OSTI]

    Anlage, Steven

    ABSTRACT Title of Document: LONGITUDINAL SPACE-CHARGE WAVES INDUCED BY ENERGY MODULATIONS Brian L. Modulations in energy or density can induce space-charge waves at low energies which could be problematic at higher energies. This thesis is a study of longitudinal space-charge waves induced by energy modulations

  10. Internal wave energy radiated from a turbulent mixed layer James R. Munroe1, a)

    E-Print Network [OSTI]

    Sutherland, Bruce

    Internal wave energy radiated from a turbulent mixed layer James R. Munroe1, a) and Bruce R of the mixed layer. In both experiments and simulations we find that the energy density of the generated waves examine mixed-layer deepening and the generation of internal waves in stratified fluid resulting from

  11. 1. INTRODUCTION The investigation of whistler waves excitation and propagation in Earth

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    disturbance near antenna was about Bmax/B0~5%. #12;High frequency probe whistler waves (f0=80-200 MHz) were magnetic field disturbance the whistler wave (frequency f0=160 MHz is close to local electron cyclotron and parametric whistler wave interaction with plasma density and magnetic field variations. Amplitude-frequency

  12. the wave model A traveling wave is an organized disturbance

    E-Print Network [OSTI]

    Winokur, Michael

    1 waves the wave model A traveling wave is an organized disturbance propagating at a well-defined wave speed v. · In transverse waves the particles of the medium move perpendicular to the direction of wave propagation. · In longitudinal waves the particles of the medium move parallel to the direction

  13. Density Functional Theory with Dissipation: Transport through Single Molecules

    SciTech Connect (OSTI)

    Kieron Burke

    2012-04-30

    A huge amount of fundamental research was performed on this grant. Most of it focussed on fundamental issues of electronic structure calculations of transport through single molecules, using density functional theory. Achievements were: (1) First density functional theory with dissipation; (2) Pseudopotential plane wave calculations with master equation; (3) Weak bias limit; (4) Long-chain conductance; and (5) Self-interaction effects in tunneling.

  14. INTERNAL SOLITARY WAVES WITH A WEAKLY STRATIFIED CRITICAL LAYER

    E-Print Network [OSTI]

    horizontal shear flow and density stratification. On a long time scale, the waves evolve and reach a quasi, we invoke nonlinear effects to re- solve this singularity. Although viscosity and thermal-fluid limit is eventually taken. Crucially, the density stratification is assumed to be small at the critical

  15. Model comparison for the density structure across solar coronal waveguides

    E-Print Network [OSTI]

    Arregui, I; Ramos, A Asensio

    2015-01-01

    The spatial variation of physical quantities, such as the mass density, across solar atmospheric waveguides governs the timescales and spatial scales for wave damping and energy dissipation. The direct measurement of the spatial distribution of density, however, is difficult and indirect seismology inversion methods have been suggested as an alternative. We applied Bayesian inference, model comparison, and model-averaging techniques to the inference of the cross-field density structuring in solar magnetic waveguides using information on periods and damping times for resonantly damped magnetohydrodynamic (MHD) transverse kink oscillations. Three commonly employed alternative profiles were used to model the variation of the mass density across the waveguide boundary. Parameter inference enabled us to obtain information on physical quantities such as the Alfv\\'en travel time, the density contrast, and the transverse inhomogeneity length scale. The inference results from alternative density models were compared a...

  16. On the wave energy potential of Western Black Sea shelf

    E-Print Network [OSTI]

    Galabov, Vasko

    2013-01-01

    In the present study we evaluate the approaches to estimate the wave energy potential of the western Black Sea shelf with numerical models. For the purpose of our evaluation and due to the lack of long time series of measurements in the selected area of the Black Sea, we compare the modeled mean wave power flux output from the SWAN wave model with the only available long term measurements from the buoy of Gelendzhik for the period 1997-2003 (with gaps). The forcing meteorological data for the numerical wave models for the selected years is extracted from the ERA Interim reanalysis of ECMWF (European Centre for Medium range Forecasts). For the year 2003 we also compare the estimated wave power with the modeled by SWAN, using ALADIN regional atmospheric model winds. We try to identify the shortcomings and limitations of the numerical modeling approach to the evaluation of the wave energy potential in Black Sea.

  17. Inertial Confinement Fusion, High Energy Density Plasmas and an Energy Source on Earth

    E-Print Network [OSTI]

    Inertial Confinement Fusion, High Energy Density Plasmas and an Energy Source on Earth Max Tabak ignition robust burn Supernova core MFE ICF ignition requires large energy and power densities Log10 Achieving the necessary multiplication of power,energy and mass densities requires a well controlled

  18. Control of Spin Waves in a Thin Film Ferromagnetic Insulator through Interfacial Spin Scattering

    E-Print Network [OSTI]

    of high-power spin waves. DOI: 10.1103/PhysRevLett.107.146602 PACS numbers: 72.25.Ba, 72.25.Mk, 72.25.Rb, 75.30.Ds Spin waves in ferromagnetic films have many unique properties and thereby have potential raise or reduce the power level to which high-power spin-wave pulses saturate due to nonlinear damping

  19. Soliton Turbulence in Shallow Water Ocean Surface Waves

    E-Print Network [OSTI]

    Costa, Andrea; Resio, Donald T; Alessio, Silvia; Chrivì, Elisabetta; Saggese, Enrica; Bellomo, Katinka; Long, Chuck E

    2014-01-01

    We analyze shallow water wind waves in Currituck Sound, North Carolina and experimentally confirm, for the first time, the presence of $soliton$ $turbulence$ in ocean waves. Soliton turbulence is an exotic form of nonlinear wave motion where low frequency energy may also be viewed as a $dense$ $soliton$ $gas$, described theoretically by the soliton limit of the Korteweg-deVries (KdV) equation, a $completely$ $integrable$ $soliton$ $system$: Hence the phrase "soliton turbulence" is synonymous with "integrable soliton turbulence." For periodic/quasiperiodic boundary conditions the $ergodic$ $solutions$ of KdV are exactly solvable by $finite$ $gap$ $theory$ (FGT), the basis of our data analysis. We find that large amplitude measured wave trains near the energetic peak of a storm have low frequency power spectra that behave as $\\sim\\omega^{-1}$. We use the linear Fourier transform to estimate this power law from the power spectrum and to filter $densely$ $packed$ $soliton$ $wave$ $trains$ from the data. We apply ...

  20. Accurate neutralino relic density

    E-Print Network [OSTI]

    Paolo Gondolo; Joakim Edsjo

    1998-04-30

    We enlarge our set of supersymmetric models and update accelerator constraints in our precise calculation of the relic density of the lightest neutralino, which includes relativistic Boltzmann averaging, subthreshold and resonant annihilations, and coannihilation processes among charginos and neutralinos.