Sample records for wave anisotropy cxs

  1. P wave anisotropy, stress, and crack distribution at Coso geothermal...

    Open Energy Info (EERE)

    Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: P wave anisotropy, stress, and crack distribution at Coso geothermal field, California...

  2. Anisotropies in the gravitational-wave stochastic background

    SciTech Connect (OSTI)

    Ölmez, S.; Mandic, V. [School of Physics and Astronomy, University of Minnesota, Minneapolis, MN 55455 (United States); Siemens, X., E-mail: olmez@physics.umn.edu, E-mail: mandic@physics.umn.edu, E-mail: siemens@gravity.phys.uwm.edu [Center for Gravitation and Cosmology, University of Wisconsin-Milwaukee, Milwaukee, WI 53201 (United States)

    2012-07-01T23:59:59.000Z

    We consider anisotropies in the stochastic background of gravitational-waves (SBGW) arising from random fluctuations in the number of gravitational-wave sources. We first develop the general formalism which can be applied to different cosmological or astrophysical scenarios. We then apply this formalism to calculate the anisotropies of SBGW associated with the fluctuations in the number of cosmic string loops, considering both cosmic string cusps and kinks. We calculate the anisotropies as a function of angle and frequency.

  3. Anisotropy and mantle flow in the Chile-Argentina subduction zone from shear wave splitting analysis

    E-Print Network [OSTI]

    Fouch, Matthew J.

    Anisotropy and mantle flow in the Chile-Argentina subduction zone from shear wave splitting subduction zone. Data is from the CHARGE network, which traversed Chile and western Argentina across two, M. L., G. Zandt, E. Triep, M. Fouch, and S. Beck (2004), Anisotropy and mantle flow in the Chile-Argentina

  4. Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia Nemat-Nasser

    E-Print Network [OSTI]

    Nemat-Nasser, Sia

    Stress-wave energy management through material anisotropy Alireza V. Amirkhizi, Aref Tehranian, Sia the required anisotropy, and to experimentally demonstrate the management of stress-wave energy in a desired that if this axis initially coincides with the stress-wave vector, then the energy of the plane waves would closely

  5. Statistical Anisotropies in Gravitational Waves in Solid Inflation

    E-Print Network [OSTI]

    Mohammad Akhshik; Razieh Emami; Hassan Firouzjahi; Yi Wang

    2014-05-16T23:59:59.000Z

    Solid inflation can support a long period of anisotropic inflation. We calculate the statistical anisotropies in the scalar and tensor power spectra and their cross-correlation in anisotropic solid inflation. The tensor-scalar cross-correlation can either be positive or negative, which impacts the statistical anisotropies of the TT and TB spectra in CMB map more significantly compared with the tensor self-correlation. The tensor power spectrum contains potentially comparable contributions from quadrupole and octopole angular patterns, which is different from the power spectra of scalar, the cross-correlation or the scalar bispectrum, where the quadrupole type statistical anisotropy dominates over octopole.

  6. Lunar Laser-Ranging Detection of Light-Speed Anisotropy and Gravitational Waves

    E-Print Network [OSTI]

    Reginald T Cahill

    2010-02-03T23:59:59.000Z

    The Apache Point Lunar Laser-ranging Operation (APOLLO), in NM, can detect photon bounces from retro-reflectors on the moon surface to 0.1ns timing resolution. This facility enables not only the detection of light speed anisotropy, which defines a local preferred frame of reference - only in that frame is the speed of light isotropic, but also fluctuations/turbulence (gravitational waves) in the flow of the dynamical 3-space relative to local systems/observers. So the APOLLO facility can act as an effective "gravitational wave" detector. A recently published small data set from November 5, 2007, is analysed to characterise both the average anisotropy velocity and the wave/turbulence effects. The results are consistent with some 13 previous detections, with the last and most accurate being from the spacecraft earth-flyby Doppler-shift NASA data.

  7. A New Light-Speed Anisotropy Experiment: Absolute Motion and Gravitational Waves Detected

    E-Print Network [OSTI]

    Reginald T Cahill

    2006-10-11T23:59:59.000Z

    Data from a new experiment measuring the anisotropy of the one-way speed of EM waves in a coaxial cable, gives the speed of light as 300,000+/-400+/-20km/s in a measured direction RA=5.5+/-2hrs, Dec=70+/-10deg S, is shown to be in excellent agreement with the results from seven previous anisotropy experiments, particularly those of Miller (1925/26), and even those of Michelson and Morley (1887). The Miller gas-mode interferometer results, and those from the RF coaxial cable experiments of Torr and Kolen (1983), De Witte (1991) and the new experiment all reveal the presence of gravitational waves, as indicated by the last +/- variations above, but of a kind different from those supposedly predicted by General Relativity. The understanding of the operation of the Michelson interferometer in gas-mode was only achieved in 2002 and involved a calibration for the interferometer that necessarily involved Special Relativity effects and the refractive index of the gas in the light paths. The results demonstrate the reality of the Fitzgerald-Lorentz contraction as an observer independent relativistic effect. A common misunderstanding is that the anisotropy of the speed of light is necessarily in conflict with Special Relativity and Lorentz symmetry - this is explained. All eight experiments and theory show that we have both anisotropy of the speed of light and relativistic effects, and that a dynamical 3-space exists - that absolute motion through that space has been repeatedly observed since 1887. These developments completely change fundamental physics and our understanding of reality.

  8. Ion anisotropy driven waves in the earth`s magnetosheath and plasma depletion layer

    SciTech Connect (OSTI)

    Denton, R.E.; Hudson, M.K. [Dartmouth Coll., Hanover, NH (United States). Dept. of Physics and Astronomy; Anderson, B.J. [Johns Hopkins Univ., Laurel, MD (United States). Applied Physics Lab.; Fuselier, S.A. [Lockheed Palo Alto Research Labs., CA (United States); Gary, S.P. [Los Alamos National Lab., NM (United States)

    1993-05-01T23:59:59.000Z

    Recent studies of low frequency waves ({omega}{sub r} {le} {Omega}{sub p}, where {Omega}{sub p} is the proton gyrofrequency) observed by AMPTE/CCE in the plasma depletion layer and magnetosheath proper arereviewed. These waves are shown to be well identified with ion cyclotron and mirror mode waves. By statistically analyzing the transitions between the magnetopause and time intervals with ion cyclotron and mirror mode waves, it is established that the regions in which ion cyclotron waves occur are between the magnetopause and the regions where the mirror mode is observed. This result is shown to follow from the fact that the wave spectral properties are ordered with respect to the proton parallel beta, {beta}{sub {parallel}p}. The later result is predicted by linear Vlasov theory using a simple model for the magnetosheath and plasma depletion layer. Thus, the observed spectral type can be associated with relative distance from the magnetopause. The anisotropy-beta relation, A{sub p} {triple_bond} (T{perpendicular}/T{sub {parallel}}){sub p} {minus} 1 = 0.50{beta}{sub {parallel}p}{sup {minus}0.48} results from the fact that the waves pitch angle scatter the particles so that the plasma is near marginal stability, and is a fundamental constraint on the plasma.

  9. Ion anisotropy driven waves in the earth's magnetosheath and plasma depletion layer

    SciTech Connect (OSTI)

    Denton, R.E.; Hudson, M.K. (Dartmouth Coll., Hanover, NH (United States). Dept. of Physics and Astronomy); Anderson, B.J. (Johns Hopkins Univ., Laurel, MD (United States). Applied Physics Lab.); Fuselier, S.A. (Lockheed Palo Alto Research Labs., CA (United States)); Gary, S.P. (Los Alamos National Lab., NM (United States))

    1993-01-01T23:59:59.000Z

    Recent studies of low frequency waves ([omega][sub r] [le] [Omega][sub p], where [Omega][sub p] is the proton gyrofrequency) observed by AMPTE/CCE in the plasma depletion layer and magnetosheath proper arereviewed. These waves are shown to be well identified with ion cyclotron and mirror mode waves. By statistically analyzing the transitions between the magnetopause and time intervals with ion cyclotron and mirror mode waves, it is established that the regions in which ion cyclotron waves occur are between the magnetopause and the regions where the mirror mode is observed. This result is shown to follow from the fact that the wave spectral properties are ordered with respect to the proton parallel beta, [beta][sub [parallel]p]. The later result is predicted by linear Vlasov theory using a simple model for the magnetosheath and plasma depletion layer. Thus, the observed spectral type can be associated with relative distance from the magnetopause. The anisotropy-beta relation, A[sub p] [triple bond] (T[perpendicular]/T[sub [parallel

  10. A New Light-Speed Anisotropy Experiment: Absolute Motion and Gravitational Waves Detected

    E-Print Network [OSTI]

    Cahill, R T

    2006-01-01T23:59:59.000Z

    Data from a new experiment measuring the anisotropy of the one-way speed of EM waves in a coaxial cable, gives the speed of light as 300,000+/-400+/-20km/s in a measured direction RA=5.5+/-2hrs, Dec=70+/-10deg S, is shown to be in excellent agreement with the results from seven previous anisotropy experiments, particularly those of Miller (1925/26), and even those of Michelson and Morley (1887). The Miller gas-mode interferometer results, and those from the RF coaxial cable experiments of Torr and Kolen (1983), De Witte (1991) and the new experiment all reveal the presence of gravitational waves, as indicated by the last +/- variations above, but of a kind different from those supposedly predicted by General Relativity. The understanding of the operation of the Michelson interferometer in gas-mode was only achieved in 2002 and involved a calibration for the interferometer that necessarily involved Special Relativity effects and the refractive index of the gas in the light paths. The results demonstrate the re...

  11. Geophys. J. Int. (1997) 129,439-449 Shear-wave anisotropy and the stress field from borehole recordings

    E-Print Network [OSTI]

    Edinburgh, University of

    Geophys. J. Int. (1997) 129,439-449 Shear-wave anisotropy and the stress field from borehole of Earth Sciences, University of Southern California, Los Angeles, CA 90089-0740, USA Accepted 1997 January 16. Received 1997 January 14; in original form 1995 August 30. S U M M A R Y 53 local earthquakes

  12. CONSTRAINTS ON THE HIGH-l POWER SPECTRUM OF MILLIMETER-WAVE ANISOTROPIES FROM APEX-SZ

    SciTech Connect (OSTI)

    Reichardt, C. L.; Zahn, O.; Ferrusca, D.; Holzapfel, W. L.; Johnson, B. R.; Lee, A. T.; Lueker, M. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Ade, P. A. R.; Lanting, T. [School of Physics and Astronomy, Cardiff University, CF24 3YB (United Kingdom); Basu, K.; Chon, G.; Kneissl, R. [Max Planck Institute for Radioastronomy, 53121 Bonn (Germany); Bender, A. N.; Halverson, N. W. [Center for Astrophysics and Space Astronomy, Department of Astrophysical and Planetary Sciences, University of Colorado, Boulder, CO 80309 (United States); Bertoldi, F. [Argelander Institute for Astronomy, Bonn University, Bonn (Germany); Cho, H.-M. [National Institute of Standards and Technology, Boulder, CO 80305 (United States); Dobbs, M.; Kennedy, J. [Department of Physics, McGill University, Montreal, H3A 2T8 (Canada); Horellou, C.; Johansson, D. [Onsala Space Observatory, Chalmers University of Technology, SE-439 92 Onsala (Sweden)] (and others)

    2009-08-20T23:59:59.000Z

    We present measurements of the angular power spectrum of millimeter wave anisotropies with the APEX-SZ instrument. APEX-SZ has mapped 0.8 deg{sup 2} of sky at a frequency of 150 GHz with an angular resolution of 1'. These new measurements significantly improve the constraints on anisotropy power at 150 GHz over the range of angular multipoles 3000 < l < 10, 000, limiting the total astronomical signal in a flat band power to be less than 105 {mu}K{sup 2} at 95% CL. We expect both submillimeter-bright, dusty galaxies and to a lesser extent secondary cosmic microwave background anisotropies from the Sunyaev-Zel'dovich effect (SZE) to significantly contribute to the observed power. Subtracting the SZE power spectrum expected for {sigma}{sub 8} = 0.8 and masking bright sources, the best-fit value for the remaining power is C {sub l} = 1.1{sup +0.9} {sub -0.8} x 10{sup -5} {mu}K{sup 2} (1.7{sup +1.4} {sub -1.3} Jy{sup 2} sr{sup -1}). This agrees well with model predictions for power due to submillimeter-bright, dusty galaxies. Comparing this power to the power detected by BLAST at 600 GHz, we find the frequency dependence of the source fluxes to be S{sub {nu}}{proportional_to}{nu}{sup 2.6+0.4}{sub -0.2}} if both experiments measure the same population of sources. Simultaneously fitting for the amplitude of the SZE power spectrum and a Poisson-distributed point source population, we place an upper limit on the matter fluctuation amplitude of {sigma}{sub 8} < 1.18 at 95% confidence.

  13. Analysis of PS-converted wave seismic data in the presence of azimuthal anisotropy 

    E-Print Network [OSTI]

    Liu, Weining

    2014-11-27T23:59:59.000Z

    Shear-wave splitting and azimuthal variations of seismic attributes are two major anisotropic effects induced by vertically-aligned fractures. They both have influences on seismic data processing and interpretation, and ...

  14. Heterogeneity and anisotropy of the lithosphere of SE Tibet from surface wave array tomography

    E-Print Network [OSTI]

    Yao, Huajian

    Understanding the geotectonic evolution of the southeastern Tibetan plateau requires knowledge about the structure of the lithosphere. Using data from 77 broadband stations in SW China, we invert Rayleigh wave phase velocity ...

  15. Detection of azimuthal anisotropy from 3-D p-wave seismic data

    E-Print Network [OSTI]

    Yildizel, Ali

    1992-01-01T23:59:59.000Z

    the equation; (II ? 1) for u(z) = V t(z) is wave slowness. Velocity estimation using reflections and the tau-p approach was first suggested by Schultz and Claerbout (1978), They showed that velocity analysis can be done in a ' similar manner... to conventional analysis by looking for maximum coherency over each ' trajectory of ellipses in r-p domain instead of a hyperbola in conventional analysis. Schultz (1982) also suggested a method of layer-stripping for velocity estimation in the r-p domain...

  16. Studying Hydraulic Fracturing through Time-variant Seismic Anisotropy

    E-Print Network [OSTI]

    Liu, Qifan

    2013-10-01T23:59:59.000Z

    . Studying seismic anisotropy by shear wave splitting can help us better understand the relationship between hydraulic fracturing and fracture systems. Shear wave splitting can be caused by fracturing and also can naturally take place in most sedimentary...

  17. Seismic response of fractures and induced anisotropy in poroelastic media

    E-Print Network [OSTI]

    Santos, Juan

    Seismic response of fractures and induced anisotropy in poroelastic media Juan E. Santos stituto) and R. Mart´inez Corredor (UNLP) Department of Mathematics, University of Calgary, October 2014 Seismic variations of velocity and attenuation of seismic waves. Seismic response of fractures and induced anisotropy

  18. Interpreting Power Anisotropy Measurements in Plasma Turbulence

    E-Print Network [OSTI]

    Chen, C H K; Horbury, T S; Schekochihin, A A

    2009-01-01T23:59:59.000Z

    A relationship between power anisotropy and wavevector anisotropy in turbulent fluctuations is derived. This can be used to interpret plasma turbulence measurements, for example in the solar wind. If fluctuations are anisotropic in shape then the ion gyroscale break point in spectra in the directions parallel and perpendicular to the magnetic field would not occur at the same frequency, and similarly for the electron gyroscale break point. This is an important consideration when interpreting solar wind observations in terms of anisotropic turbulence theories. Model magnetic field power spectra are presented assuming a cascade of critically balanced Alfven waves in the inertial range and kinetic Alfven waves in the dissipation range. The variation of power anisotropy with scale is compared to existing solar wind measurements and the similarities and differences are discussed.

  19. The elastic anisotropy of marble

    E-Print Network [OSTI]

    Gebhard, Susan Nash

    1982-01-01T23:59:59.000Z

    on acoustic anisotropy in marble has been shown to be negligable in four naturally-deformed samples. Compressional-wave velocities in each of the samples were calculated from the single crystal elastic constants of calcite and the orien- tat1ons... thanks to my husband, Fred Tubb, for his patience and support. This research was supported by the National Science Foundation under grant OCN 7817919 and Office of Naval Research contract N-00014- 80-0-0013. To my mother and father, for al1...

  20. Stratification of anisotropy in the Pacific upper mantle Daniel B. Smith, Michael H. Ritzwoller, and Nikolai M. Shapiro

    E-Print Network [OSTI]

    Shapiro, Nikolai

    Stratification of anisotropy in the Pacific upper mantle Daniel B. Smith, Michael H. Ritzwoller: surface waves, azimuthal anisotropy, Pacific Citation: Smith, D. B., M. H. Ritzwoller, and N. M. Shapiro

  1. Waves

    E-Print Network [OSTI]

    LaCure, Mari Mae

    2010-04-29T23:59:59.000Z

    Waves is the supporting document to the Master of Fine Arts thesis exhibition of the same title. Exhibited March 7-12 2010 in the Art and Design Gallery at the University of Kansas, Waves was comprised of a series of mixed media drawings...

  2. Semiclassical suppression of weak anisotropies of a generic Universe

    E-Print Network [OSTI]

    Marco Valerio Battisti; Riccardo Belvedere; Giovanni Montani

    2009-06-11T23:59:59.000Z

    A semiclassical mechanism which suppresses the weak anisotropies of an inhomogeneous cosmological model is developed. In particular, a wave function of this Universe having a meaningful probabilistic interpretation is obtained that is in agreement with the Copenhagen School. It describes the evolution of the anisotropies with respect to the isotropic scale factor which is regarded as a semiclassical variable playing an observer-like role. Near the cosmological singularity the solution spreads over all values of the anisotropies while, when the Universe expands sufficiently, the closed Friedmann-Robertson-Walker model appears to be the favorite state.

  3. Ion temperature anisotropy limitation in high beta plasmas

    SciTech Connect (OSTI)

    Scime, Earl E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Keiter, Paul A. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Balkey, Matthew M. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Boivin, Robert F. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Kline, John L. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Blackburn, Melanie [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Gary, S. Peter [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

    2000-05-01T23:59:59.000Z

    Measurements of parallel and perpendicular ion temperatures in the Large Experiment on Instabilities and Anisotropies (LEIA) space simulation chamber display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta ({beta}=8{pi}nkT/B{sup 2}). Fluctuation measurements indicate the presence of low frequency, transverse, electromagnetic waves with wave numbers and frequencies that are consistent with predictions for Alfven Ion Cyclotron instabilities. These observations are also consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound on the ion temperature anisotropy is imposed by scattering from enhanced fluctuations due to growth of the Alfven ion cyclotron instability. (c) 2000 American Institute of Physics.

  4. Structure and evolution of the Australian continent : insights from seismic and mechanical heterogeneity and anisotropy

    E-Print Network [OSTI]

    Simons, Frederik Jozef Maurits, 1974-

    2002-01-01T23:59:59.000Z

    In this thesis, I explore the geophysical structure and evolution of the Australian continental lithosphere. I combine insights from isotropic and anisotropic seismic surface-wave tomography with an analysis of the anisotropy ...

  5. SELF-CONSISTENT ION CYCLOTRON ANISOTROPY-BETA RELATION FOR SOLAR WIND PROTONS

    SciTech Connect (OSTI)

    Isenberg, Philip A. [Institute for the Study of Earth, Oceans, and Space, University of New Hampshire, Durham, NH 03824 (United States); Maruca, Bennett A. [Space Sciences Laboratory, University of California, Berkeley, CA 94720 (United States); Kasper, Justin C., E-mail: phil.isenberg@unh.edu, E-mail: bmaruca@ssl.berkeley.edu, E-mail: jkasper@cfa.harvard.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2013-08-20T23:59:59.000Z

    We derive a set of self-consistent marginally stable states for a system of ion-cyclotron waves propagating parallel to the large-scale magnetic field through a homogeneous proton-electron plasma. The proton distributions and the wave dispersions are related through the condition that no further ion-cyclotron resonant particle scattering or wave growth/damping may take place. The thermal anisotropy of the protons in these states therefore defines the threshold value for triggering the proton-cyclotron anisotropy instability. A number of recent papers have noted that the anisotropy of solar wind protons at 1 AU does not seem to be limited by the proton-cyclotron anisotropy threshold, even at low plasma beta. However, this puzzle seems to be due solely to the estimation of this anisotropy threshold under the assumption that the protons have a bi-Maxwellian distribution. We note that bi-Maxwellian distributions are never marginally stable to the resonant cyclotron interaction, so these estimates do not represent physically valid thresholds. The threshold anisotropies obtained from our marginally stable states are much larger, as a function of proton parallel beta, than the bi-Maxwellian estimates, and we show that the measured data remains below these more rigorous thresholds. Thus, the results of this paper resolve the apparent contradiction presented by the solar wind anisotropy observations at 1 AU: the bi-Maxwellian anisotropies are not rigorous thresholds, and so do not limit the proton distributions in the solar wind.

  6. Competing effects of magnetocrystalline anisotropy and exchange...

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

    effects of magnetocrystalline anisotropy and exchange bias in epitaxial FeIrMn bilayers. Competing effects of magnetocrystalline anisotropy and exchange bias in epitaxial FeIrMn...

  7. Permeability anisotropy and resistivity anisotropy of mechanically compressed mudrocks

    E-Print Network [OSTI]

    Adams, Amy Lynn

    2014-01-01T23:59:59.000Z

    Permeability anisotropy (the ratio of the horizontal to vertical permeability) is an important parameter used in sedimentary basin models and geotechnical design to model fluid flow, locate hydrocarbon reserves and estimate ...

  8. Wind anisotropies and GRB progenitors

    E-Print Network [OSTI]

    Georges Meynet; Andre Maeder

    2007-01-17T23:59:59.000Z

    We study the effect of wind anisotropies on the stellar evolution leading to collapsars. Rotating models of a 60 M$_\\odot$ star with $\\Omega/\\Omega_{\\rm crit}=0.75$ on the ZAMS, accounting for shellular rotation and a magnetic field, with and without wind anisotropies, are computed at $Z$=0.002 until the end of the core He-burning phase. Only the models accounting for the effects of the wind anisotropies retain enough angular momentum in their core to produce a Gamma Ray Burst (GRB). The chemical composition is such that a type Ic supernova event occurs. Wind anisotropies appear to be a key physical ingredient in the scenario leading to long GRBs.

  9. Seismic anisotropy of fractured rock

    E-Print Network [OSTI]

    M. Schoenberg, C. M. Sayers

    2000-02-18T23:59:59.000Z

    of seismic anisotropy to determine the orientation of fracture sets is of ... this assumption of noninteraction does not imply that the ... conventional (2-subscript) condensed 6 x 6 matrix notation,. 11. 6, while ... have simple physical interpretations.

  10. TACMB-1: The Theory of Anisotropies in the Cosmic Microwave Background (Bibliographic Resource Letter)

    E-Print Network [OSTI]

    Martin White; J. D. Cohn

    2002-03-07T23:59:59.000Z

    This Resource Letter provides a guide to the literature on the theory of anisotropies in the cosmic microwave background. Journal articles, web pages, and books are cited for the following topics: discovery, cosmological origin, early work, recombination, general CMB anisotropy references, primary CMB anisotropies (numerical, analytical work), secondary effects, Sunyaev-Zel'dovich effect(s), lensing, reionization, polarization, gravity waves, defects, topology, origin of fluctuations, development of fluctuations, inflation and other ties to particle physics, parameter estimation, recent constraints, web resources, foregrounds, observations and observational issues, and gaussianity.

  11. Thickness dependence of magnetic anisotropy in thin Ni films electrodeposited onto the (011) and (001) surfaces of n-GaAs

    SciTech Connect (OSTI)

    Gubbiotti, G.; Carlotti, G.; Tacchi, S.; Liu, Y.-K.; Scheck, C.; Schad, R.; Zangari, G. [INFM CRS-SOFT, c/o Universita di Roma 'La Sapienza', I-00185, Rome (Italy); INFM UdR-Perugia, c/o Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); INFM-National Center for nanoStructures and bioSystem at Surfaces (S3) Modena, and Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); IINFM UdR-Perugia, Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); MINT Center, University of Alabama, Tuscaloosa Alabama 35401 (United States); Department of Materials Science and Engineering and Center for Electrochemical Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

    2005-05-15T23:59:59.000Z

    Brillouin light scattering from thermal spin waves has been exploited to investigate the thickness dependence of magnetic anisotropy of Ni films, with thickness in the range 7-35 nm, grown by electrodeposition onto either (011)- or (001)-GaAs substrates. In the former case, Ni films exhibit a well-defined in-plane uniaxial anisotropy induced by the symmetry of the substrate. In the case of the (001)-GaAs substrate, instead, the magnetic anisotropy results from a combination of both a fourfold and a twofold contribution. The physical mechanisms responsible for the observed anisotropy, as well as its dependence on film thickness, are discussed in detail.

  12. Layering and temperature-dependent magnetization and anisotropy of naturally produced Ni/NiO multilayers

    SciTech Connect (OSTI)

    Pappas, S. D.; Trachylis, D.; Velgakis, M. J. [Laboratory of High-Tech Materials, School of Engineering, University of Patras, 26504 Patras (Greece); Kapaklis, V.; Joensson, P. E.; Papaioannou, E. Th. [Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20 Uppsala (Sweden); Delimitis, A. [Chemical Process Engineering Research Institute (CPERI), Centre for Research and Technology Hellas (CERTH), 57001 Thermi, Thessaloniki (Greece); Poulopoulos, P. [Laboratory of High-Tech Materials, School of Engineering, University of Patras, 26504 Patras (Greece); Institut fuer Experimentalphysik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin-Dahlem (Germany); Materials Science Department, University of Patras, 26504 Patras (Greece); Fumagalli, P. [Institut fuer Experimentalphysik, Freie Universitaet Berlin, Arnimallee 14, D-14195 Berlin-Dahlem (Germany); Politis, C. [Laboratory of High-Tech Materials, School of Engineering, University of Patras, 26504 Patras (Greece); Department of Materials Science and Engineering, University of Texas at Arlington, Arlington, Texas 76019 (United States)

    2012-09-01T23:59:59.000Z

    Ni/NiO multilayers were grown by magnetron sputtering at room temperature, with the aid of the natural oxidation procedure. That is, at the end of the deposition of each single Ni layer, air is let to flow into the vacuum chamber through a leak valve. Then, a very thin NiO layer ({approx}1.2 nm) is formed. Simulated x-ray reflectivity patterns reveal that layering is excellent for individual Ni-layer thickness larger than 2.5 nm, which is attributed to the intercalation of amorphous NiO between the polycrystalline Ni layers. The magnetization of the films, measured at temperatures 5-300 K, has almost bulk-like value, whereas the films exhibit a trend to perpendicular magnetic anisotropy (PMA) with an unusual significant positive interface anisotropy contribution, which presents a weak temperature dependence. The power-law behavior of the multilayers indicates a non-negligible contribution of higher order anisotropies in the uniaxial anisotropy. Bloch-law fittings for the temperature dependence of the magnetization in the spin-wave regime show that the magnetization in the multilayers decreases faster as a function of temperature than the one of bulk Ni. Finally, when the individual Ni-layer thickness decreases below 2 nm, the multilayer stacking vanishes, resulting in a dramatic decrease of the interface magnetic anisotropy and consequently in a decrease of the perpendicular magnetic anisotropy.

  13. Gravimagnetic shock waves in the anisotropic plasma

    E-Print Network [OSTI]

    Yu. G. Ignatyev; D. N. Gorokhov

    2011-01-01T23:59:59.000Z

    The relativistic magnetohydrodynamic equations for the anisotropic magnetoactive plasma are obtained and accurately integrated in the plane gravitational wave metrics. The dependence of the induction mechanism of the gravimagnetic shock waves on the degree of the magnetoactive plasma anisotropy is analyzed.

  14. Drift kinetic Alfvén wave in temperature anisotropic plasma

    SciTech Connect (OSTI)

    Naim, Hafsa, E-mail: roohi-phy@yahoo.com; Bashir, M. F. [Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan) [Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan)] [Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan)

    2014-03-15T23:59:59.000Z

    By using the gyrokinetic theory, the kinetic Alfvén waves (KAWs) are discussed to emphasize the drift effects through the density inhomogeneity and the temperature anisotropy on their dispersion characteristics. The dependence of stabilization mechanism of the drift-Alfvén wave instability on the temperature anisotropy is highlighted. The estimate of the growth rate and the threshold condition for a wide range of parameters are also discussed.

  15. High anisotropy materials for magnetic nanotechnologies

    E-Print Network [OSTI]

    Shipton, Erik G.

    2011-01-01T23:59:59.000Z

    anisotropy in rare earth transition metal alloys originatesfor transition metals than for rare earth. The atomicmetal sublattice and negative exchange between the CoPd and the rare earth

  16. Dynamical models with a general anisotropy profile

    E-Print Network [OSTI]

    M. Baes; E. Van Hese

    2007-05-28T23:59:59.000Z

    Both numerical simulations and observational evidence indicate that the outer regions of galaxies and dark matter haloes are typically mildly to significantly radially anisotropic. The inner regions can be significantly non-isotropic, depending on the dynamical formation and evolution processes. In an attempt to break the lack of simple dynamical models that can reproduce this behaviour, we explore a technique to construct dynamical models with an arbitrary density and an arbitrary anisotropy profile. We outline a general construction method and propose a more practical approach based on a parameterized anisotropy profile. This approach consists of fitting the density of the model with a set of dynamical components, each of which have the same anisotropy profile. Using this approach we avoid the delicate fine-tuning difficulties other fitting techniques typically encounter when constructing radially anisotropic models. We present a model anisotropy profile that generalizes the Osipkov-Merritt profile, and that can represent any smooth monotonic anisotropy profile. Based on this model anisotropy profile, we construct a very general seven-parameter set of dynamical components for which the most important dynamical properties can be calculated analytically. We use the results to look for simple one-component dynamical models that generate simple potential-density pairs while still supporting a flexible anisotropy profile. We present families of Plummer and Hernquist models in which the anisotropy at small and large radii can be chosen as free parameters. We also generalize these two families to a three-parameter family that self-consistently generates the set of Veltmann potential-density pairs. (Abridged...)

  17. Wind anisotropy and stellar evolution

    E-Print Network [OSTI]

    Cyril Georgy; Georges Meynet; André Maeder

    2008-07-31T23:59:59.000Z

    Mass loss is a determinant factor which strongly affects the evolution and the fate of massive stars. At low metallicity, stars are supposed to rotate faster than at the solar one. This favors the existence of stars near the critical velocity. In this rotation regime, the deformation of the stellar surface becomes important, and wind anisotropy develops. Polar winds are expected to be dominant for fast rotating hot stars. These polar winds allow the star to lose large quantities of mass and still retain a high angular momentum, and they modifie the evolution of the surface velocity and the final angular momentum kept in the star's core. We show here how these winds affect the final stages of massive stars, according to our knowledge about Gamma Ray Bursts. Computation of theoretical Gamma Ray Bursts rate indicates that our models have too fast rotating cores, and that we need to include an additional effect to spin them down. Magnetic fields in stars act in this direction, and we show how they modify the evolution of massive star up to the final stages.

  18. Imaging CSEM data in the presence of electrical anisotropy

    SciTech Connect (OSTI)

    Newman, G.A.; Commer, M.; Carazzone, J.J.

    2009-09-10T23:59:59.000Z

    Formation anisotropy should be incorporated into the analysis of controlled source electromagnetic (CSEM) data because failure to do so can produce serious artifacts in the resulting resistivity images for certain data configurations of interest. This finding is demonstrated in model and case studies. Sensitivity to horizontal resistivity will be strongest in the broadside electric field data where detectors are offset from the tow line. Sensitivity to the vertical resistivity is strongest for over flight data where the transmitting antenna passes directly over the detecting antenna. Consequently, consistent treatment of both over flight and broadside electric field measurements requires an anisotropic modeling assumption. To produce a consistent resistivity model for such data we develop and employ a 3D CSEM imaging algorithm that treats transverse anisotropy. The algorithm is based upon non-linear conjugate gradients and full wave equation modeling. It exploits parallel computing systems to effectively treat 3D imaging problems and CSEM data volumes of industrial size. Here we use it to demonstrate the anisotropic imaging process on model and field data sets from the North Sea and offshore Brazil. We also verify that isotropic imaging of over flight data alone produces an image generally consistent with the vertical resistivity. However, superior data fits are obtained when the same over flight data are analyzed assuming an anisotropic resistivity model.

  19. Predicting stress-induced velocity anisotropy in rocks

    SciTech Connect (OSTI)

    Mavko, G.; Mukerji, T.; Godfrey, N. [Stanford Univ., CA (United States). Rock Physics Lab.] [Stanford Univ., CA (United States). Rock Physics Lab.

    1995-07-01T23:59:59.000Z

    A simple transformation, using measured isotropic V{sub P} and V{sub S} versus hydrostatic pressure, is presented for predicting stress-induced seismic velocity anisotropy in rocks. The compliant, crack-like portions of the pore space are characterized by generalized compressional and shear compliances that are estimated form the isotropic V{sub P} and V{sub S}. The physical assumption that the compliant porosity is crack-like means that the pressure dependence of the generalized compliances is governed primarily by normal tractions resolved across cracks and defects. This allows the measured pressure dependence to be mapped form the hydrostatic stress state to any applied nonhydrostatic stress. Predicted P- and S-wave velocities agree reasonably well with uniaxial stress data for Barre Granite and Massillon Sandstone. While it is mechanically similar to methods based on idealized ellipsoidal cracks, the approach is relatively independent of any assumed crack geometry and is not limited to small crack densities.

  20. Inflation and CMB Anisotropy from Quantum Metric Fluctuations

    E-Print Network [OSTI]

    Leonid Marochnik; Daniel Usikov

    2015-02-08T23:59:59.000Z

    We propose a model of cosmological evolution of the early and late Universe which is consistent with observational data and naturally explains the origin of inflation and dark energy. We show that the de Sitter accelerated expansion of the FLRW space with no matter fields (hereinafter, empty space) is its natural state, and the model does not require either a scalar field or cosmological constant or any other hypotheses. This is due to the fact that the de Sitter state is an exact solution of the rigorous mathematically consistent equations of one-loop quantum gravity for the empty FLRW space that are finite off the mass shell. Space without matter fields is not empty, as it always has the natural quantum fluctuations of the metric, i.e. gravitons. Therefore, the empty (in this sense) space is filled with gravitons, which have the backreaction effect on its evolution over time forming a self-consistent de Sitter instanton leading to the exponentially accelerated expansion of the Universe. At the start and the end of cosmological evolution, the Universe is assumed to be empty, which explains the origin of inflation and dark energy. This scenario leads to the prediction that the signs of the parameter 1+w should be opposite in both cases, and this fact is consistent with observations. The fluctuations of the number of gravitons lead to fluctuations of their energy density which in turn leads to the observed CMB temperature anisotropy of the order of 10^-5 and CMB polarization. In the frame of this scenario, it is not a hypothetical scalar field that generates inflation and relic gravitational waves but on the contrary, the gravitational waves (gravitons) generate dark energy, inflation, CMB anisotropy and polarization.

  1. Cosmological Rotation of Quantum-Mechanical Origin and Anisotropy of the Microwave Background

    E-Print Network [OSTI]

    L. P. Grishchuk

    1993-10-06T23:59:59.000Z

    It is shown that rotational cosmological perturbations can be generated in the early Universe, similarly to gravitational waves. The generating mechanism is quantum-mechanical in its nature, and the created perturbations should now be placed in squeezed vacuum quantum states. The physical conditions under which the phenomenon can occur are formulated. The generated perturbations can contribute to the large-angular-scale anisotropy of the cosmic microwave background radiation. An exact formula is derived for the angular correlation function of the temperature variations caused by the quantum-mechanically generated rotational perturbations. The multipole expansion begins from the dipole component. The comparison with the case of gravitational waves is made.

  2. Preferred orientation and elastic anisotropy in shales.

    SciTech Connect (OSTI)

    Lonardelli, I.; Wenk, H.-R.; Ren, Y.; Univ. of California at Berkeley

    2007-03-01T23:59:59.000Z

    Anisotropy in shales is becoming an important issue in exploration and reservoir geophysics. In this study, the crystallographic preferred orientation of clay platelets that contributes to elastic anisotropy was determined quantitatively by hard monochromatic X-ray synchrotron diffraction in two different shales from drillholes off the coast of Nigeria. To analyze complicated diffraction images with five different phases (illite/smectite, kaolinite, quartz, siderite, feldspar) and many overlapping peaks, we applied a methodology based on the crystallographic Rietveld method. The goal was to describe the intrinsic physical properties of the sample (phase composition, crystallographic preferred orientation, crystal structure, and microstructure) and compute macroscopic elastic properties by averaging single crystal properties over the orientation distribution for each phase. Our results show that elastic anisotropy resulting from crystallographic preferred orientation of the clay particles can be determined quantitatively. This provides a possible way to compare measured seismic anisotropy and texture-derived anisotropy and to estimate the contribution of the low-aspect ratio pores aligned with bedding.

  3. COSMIC-RAY TRANSPORT AND ANISOTROPIES

    SciTech Connect (OSTI)

    Biermann, Peter L. [MPI for Radioastronomy, Auf dem Huegel 69, D-53121 Bonn (Germany); Becker Tjus, Julia; Mandelartz, Matthias [Ruhr-Universitaet Bochum, Fakultaet fuer Physik and Astronomie, Theoretische Physik I, D-44780 Bochum (Germany); Seo, Eun-Suk [Department of Physics, University of Maryland, College Park, MD 20742 (United States)

    2013-05-10T23:59:59.000Z

    We show that the large-scale cosmic-ray anisotropy at {approx}10 TeV can be explained by a modified Compton-Getting effect in the magnetized flow field of old supernova remnants. Cosmic rays arrive isotropically to the flow field and are then carried along with the flow to produce a large-scale anisotropy in the arrival direction. This approach suggests an optimum energy scale for detecting the anisotropy. Two key assumptions are that propagation is based on turbulence following a Kolmogorov law and that cosmic-ray interactions are dominated by transport via cosmic-ray-excited magnetic irregularities through the stellar wind of an exploding star and its shock shell. A prediction is that the amplitude is smaller at lower energies due to incomplete sampling of the velocity field and also smaller at larger energies due to smearing.

  4. Gravity Waves Gravity Waves

    E-Print Network [OSTI]

    Weijgaert, Rien van de

    ;14/03/2014 6 H L H L L Phase & Group Velocity #12;14/03/2014 7 Doppler Effect #12;14/03/2014 8 Shock Waves #12;14/03/2014 14 Supernova Remnant Cassiopeia A Supernova blast waves #12;14/03/2014 15 Tycho's Remnant (SN 1572AD A SNR flythrough Theory of Supernova Blast Waves Supernovae: Type Ia Subsonic deflagration wave turning

  5. Determination of Near-Surface Anisotropy From Surface Electromagnetic Data

    E-Print Network [OSTI]

    Al-Dajani, AbdulFattah

    2001-01-01T23:59:59.000Z

    Ground penetrating radar (GPR) signatures, such as reflection moveout, are sensitive to the presence of azimuthal anisotropy. Azimuthal anisotropy can occur as an intrinsic property of the medium and/or due to the presence ...

  6. Resolution of reservoir scale electrical anisotropy from marine CSEM data

    E-Print Network [OSTI]

    Brown, V.

    2013-01-01T23:59:59.000Z

    and K. , Helbig, 1994, Oilfield anisotropy--its originscharacteristics: Schlumberger Oilfield Review, 6.4, 48-56.

  7. P and SV waves 3-D Numerical Modeling of AVOA from Heterogeneous Fractured Reservoirs

    E-Print Network [OSTI]

    Zhu, Xiang

    1997-01-01T23:59:59.000Z

    We study the effects of fracture-induced anisotropy and lateral fracture density heterogeneity on the reflected P and SV wave amplitude variation with offset and azimuth (AVOA), using 3-D finite-difference simulations. The ...

  8. Relative sensitivity of formability to anisotropy

    SciTech Connect (OSTI)

    Logan, R.W.; Maker, B.N.

    1997-01-01T23:59:59.000Z

    This work compares the relative importance of material anisotropy in sheet forming as compared to other material and process variables. The comparison is made quantitative by the use of normalized dependencies of depth to failure (forming limit is reached) on various measures of anisotropy, as well as strain and rate sensitivity, friction, and tooling. Comparisons are made for a variety of forming processes examined previously in the literature as well as two examples of complex stampings in this work. 7 The examples rover a range from nearly pure draw to nearly pure stretch situations, and show that for materials following a quadratic yield criterion, anisotropy is among the most sensitive parameters influencing formability. For materials following higher-exponent yield criteria, the dependency is milder but is still of the order of most other process parameters. However, depending on the particular forming operation, it is shown that in some cases anisotropy may be ignored, whereas in others its consideration is crucial to a good quality analysis.

  9. Numerical likelihood analysis of cosmic ray anisotropies

    SciTech Connect (OSTI)

    Carlos Hojvat et al.

    2003-07-02T23:59:59.000Z

    A numerical likelihood approach to the determination of cosmic ray anisotropies is presented which offers many advantages over other approaches. It allows a wide range of statistically meaningful hypotheses to be compared even when full sky coverage is unavailable, can be readily extended in order to include measurement errors, and makes maximum unbiased use of all available information.

  10. The Standard Cosmological Model and CMB Anisotropies

    E-Print Network [OSTI]

    James G. Bartlett

    1999-03-17T23:59:59.000Z

    This is a course on cosmic microwave background (CMB) anisotropies in the standard cosmological model, designed for beginning graduate students and advanced undergraduates. ``Standard cosmological model'' in this context means a Universe dominated by some form of cold dark matter (CDM) with adiabatic perturbations generated at some initial epoch, e.g., Inflation, and left to evolve under gravity alone (which distinguishes it from defect models). The course is primarily theoretical and concerned with the physics of CMB anisotropies in this context and their relation to structure formation. Brief presentations of the uniform Big Bang model and of the observed large--scale structure of the Universe are given. The bulk of the course then focuses on the evolution of small perturbations to the uniform model and on the generation of temperature anisotropies in the CMB. The theoretical development is performed in the (pseudo--)Newtonian gauge because it aids intuitive understanding by providing a quick reference to classical (Newtonian) concepts. The fundamental goal of the course is not to arrive at a highly exact nor exhaustive calculation of the anisotropies, but rather to a good understanding of the basic physics that goes into such calculations.

  11. The expected anisotropy in solid inflation

    E-Print Network [OSTI]

    Nicola Bartolo; Marco Peloso; Angelo Ricciardone; Caner Unal

    2014-07-30T23:59:59.000Z

    Solid inflation is an effective field theory of inflation in which isotropy and homogeneity are accomplished via a specific combination of anisotropic sources (three scalar fields that individually break isotropy). This results in specific observational signatures that are not found in standard models of inflation: a non-trivial angular dependence for the squeezed bispectrum, and a possibly long period of anisotropic inflation (to drive inflation, the "solid" must be very insensitive to any deformation, and thus background anisotropies are very slowly erased). In this paper we compute the expected level of statistical anisotropy in the power spectrum of the curvature perturbations of this model. To do so, we account for the classical background values of the three scalar fields that are generated on large (superhorizon) scales during inflation via a random walk sum, as the perturbation modes leave the horizon. Such an anisotropy is unavoidably generated, even starting from perfectly isotropic classical initial conditions. The expected level of anisotropy is related to the duration of inflation and to the amplitude of the squeezed bispectrum. If this amplitude is close to its current observational limit (so that one of the most interesting predictions of the model can be observed in the near future), we find that a level of statistical anisotropy $\\gtrsim 3\\%$ in the power spectrum is to be expected, if inflation lasted $\\gtrsim 20-30$ e-folds more than the final $50-60$ efolds required to generare the CMB modes. We also comment and point out various similarities between solid inflation and models of inflation where a suitable coupling of the inflaton to a vector kinetic term $F^{2}$ gives frozen and scale invariant vector perturbations on superhorizon scales.

  12. Residual stress measurement on ductile cast iron using critically refracted longitudinal (Lcr) wave technique

    E-Print Network [OSTI]

    Chundu, Srinivasulu Naidu

    1991-01-01T23:59:59.000Z

    . Temperature is an important factor that has significant effect on the velocity of L wave in ductile cast iron. Fully annealed and as-cast test bars were investigated to study the effect of temperature in the absence and presence of residual stresses.... Effect of Anisotropy in the Present Investigation l. Introduction . . 2. Examining the Test Bars for Anisotropy VIII. DETECTION OF STRESSES IN SHOT PEENED AND SHOT BLASTED DUCTILE IRON SAMPLES APPLYING LcR WAVE TECHNIQUE. . . . . . . . . . . . . A...

  13. Studies of anisotropy of iron based superconductors

    SciTech Connect (OSTI)

    Murphy, Jason [Ames Laboratory

    2013-05-15T23:59:59.000Z

    To study the electronic anisotropy in iron based superconductors, the temperature dependent London penetration depth, {Delta}{lambda}#1;#21;(T), have been measured in several compounds, along with the angular dependent upper critical field, H{sub c2}(T). Study was undertaken on single crystals of Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} with x=0.108 and x=0.127, in the overdoped range of the doping phase diagram, characterized by notable modulation of the superconducting gap. Heavy ion irradiation with matching field doses of 6 T and 6.5 T respectively, were used to create columnar defects and to study their effect on the temperature {Delta}{lambda}#1;#21;(T). The variation of the low-temperature penetration depth in both pristine and irradiated samples was #12;tted with a power-law function {Delta}{lambda}#1;#21;(T) = AT{sup n}. Irradiation increases the magnitude of the pre-factor A and decreases the exponent n, similar to the effect on the optimally doped samples. This finding supports the universal s{sub {+-}}#6; scenario for the whole doping range. Knowing that the s{sub {+-}}#6; gap symmetry exists across the superconducting dome for the electron doped systems, we next looked at {lambda}#21;(T), in optimally - doped, SrFe{sub 2}(As{sub 1-x}P{sub x}){sub 2}, x =0.35. Both, as-grown (T{sub c} ~ #25;25 K) and annealed (T{sub c} ~ #25;35 K) single crystals of SrFe{sub 2}(As{sub 1-x}P{sub x}){sub 2} were measured. Annealing decreases the absolute value of the London penetration depth from #21;{lambda}(0) = 300 {+-}#6; 10 nm in as-grown samples to {lambda}#21;(0) = 275{+-}#6;10 nm. At low temperatures, {lambda}#21;(T) #24;~ T indicates a superconducting gap with line nodes. Analysis of the full-temperature range superfluid density is consistent with the line nodes, but differs from the simple single-gap d-wave. The observed behavior is very similar to that of BaFe{sub 2}(As{sub 1-x}P{sub x}){sub 2}, showing that isovalently substituted pnictides are inherently different from the charge-doped materials. In-plane resistivity measurements as a function of temperature, magnetic field, and its orientation with respect to the crystallographic ab-plane were used to study the upper critical field, H{sub c2}, of two overdoped compositions of Ba(Fe{sub 1-x}Ni{sub x}){sub 2}As{sub 2}, x=0.054 and x=0.072. Measurements were performed using precise alignment (with accuracy less than 0.1{degree}) of the magnetic field with respect to the Fe-As plane. The dependence of the H{sub c2} on angle {theta}#18; between the field and the ab- plane was measured in isothermal conditions in a broad temperature range. We found that the shape of the H{sub c2} vs. {theta}#18; curve clearly deviates from the Ginzburg-Landau theory.

  14. Weibel instability for a streaming electron, counterstreaming e-e, and e-p plasmas with intrinsic temperature anisotropy

    SciTech Connect (OSTI)

    Ghorbanalilu, M. [Physics Department, Shahid Beheshti University, G. C., Tehran (Iran, Islamic Republic of) [Physics Department, Shahid Beheshti University, G. C., Tehran (Iran, Islamic Republic of); Physics Department, Azarbaijan Shahid Madani University, Tabriz (Iran, Islamic Republic of); Sadegzadeh, S.; Ghaderi, Z. [Physics Department, Azarbaijan Shahid Madani University, Tabriz (Iran, Islamic Republic of)] [Physics Department, Azarbaijan Shahid Madani University, Tabriz (Iran, Islamic Republic of); Niknam, A. R. [Laser-Plasma Research Institute, Shahid Beheshti University, G. C., Tehran (Iran, Islamic Republic of)] [Laser-Plasma Research Institute, Shahid Beheshti University, G. C., Tehran (Iran, Islamic Republic of)

    2014-05-15T23:59:59.000Z

    The existence of Weibel instability for a streaming electron, counterstreaming electron-electron (e-e), and electron-positron (e-p) plasmas with intrinsic temperature anisotropy is investigated. The temperature anisotropy is included in the directions perpendicular and parallel to the streaming direction. It is shown that the beam mean speed changes the instability mode, for a streaming electron beam, from the classic Weibel to the Weibel-like mode. The analytical and numerical solutions approved that Weibel-like modes are excited for both counterstreaming e-e and e-p plasmas. The growth rates of the instabilities in e-e and e-p plasmas are compared. The growth rate is larger for e-p plasmas if the thermal anisotropy is small and the opposite is true for large thermal anisotropies. The analytical and numerical solutions are in good agreement only in the small parallel temperature and wave number limits, when the instability growth rate increases linearly with normalized wave number kc??{sub p}.

  15. Microstructures and petro-fabrics of lawsonite blueschist in the North Qilian suture zone, NW China: Implications for seismic anisotropy of

    E-Print Network [OSTI]

    Jung, Haemyeong

    are much stronger in foliated LBS than in massive LBS. In addition, a kinematic vorticity analysis suggests anisotropies occurs between glaucophane and lawsonite, the delay time of fast S-wave polarization an- isotropy). Hydrous minerals are therefore consid- ered to have enormous implications for the transportation of water

  16. Generation of Gravitational Waves and Scalar Perturbations in Inflation with Effective $?$-term and T/S Story

    E-Print Network [OSTI]

    V. N. Lukash; E. V. Mikheeva

    1998-03-06T23:59:59.000Z

    We argue that gravitational wave contribution to the cosmic microwave background anisotropy at angular scale $\\sim 10^0$ may exceed 50% for some models of hybrid inflation producing standard cosmology with the density perturbation slope $n \\simeq 1$.

  17. LIMITS ON ALPHA PARTICLE TEMPERATURE ANISOTROPY AND DIFFERENTIAL FLOW FROM KINETIC INSTABILITIES: SOLAR WIND OBSERVATIONS

    SciTech Connect (OSTI)

    Bourouaine, Sofiane; Verscharen, Daniel; Chandran, Benjamin D. G. [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States)] [Space Science Center, University of New Hampshire, Durham, NH 03824 (United States); Maruca, Bennett A. [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States)] [Space Science Laboratory, University of California, Berkeley, CA 94720 (United States); Kasper, Justin C., E-mail: s.bourouaine@unh.edu [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA 02138 (United States)

    2013-11-01T23:59:59.000Z

    Previous studies have shown that the observed temperature anisotropies of protons and alpha particles in the solar wind are constrained by theoretical thresholds for pressure and anisotropy driven instabilities such as the Alfvén/ion-cyclotron (A/IC) and fast-magnetosonic/whistler (FM/W) instabilities. In this Letter, we use a long period of in situ measurements provided by the Wind spacecraft's Faraday cups to investigate the combined constraint on the alpha proton differential flow velocity and the alpha particle temperature anisotropy due to A/IC and FM/W instabilities. We show that the majority of the data are constrained to lie within the region of parameter space in which A/IC and FM/W waves are either stable or have extremely low growth rates. In the minority of observed cases in which the growth rate of the A/IC (FM/W) instability is comparatively large, we find relatively higher values of T {sub ?}/T {sub p} (T {sub ??}/T {sub ?p}) when the alpha proton differential flow velocity is small, where T {sub ?} and T {sub p} (T {sub ??} and T {sub ?p}) are the perpendicular (parallel) temperatures of alpha particles and protons. We conjecture that this observed feature might arise from preferential alpha particle heating which can drive the alpha particles beyond the instability thresholds.

  18. anisotropy contrast study: Topics by E-print Network

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

    this location. Antoine Letessier-Selvon; Pierre Auger Collaboration 2006-10-05 3 Studying Hydraulic Fracturing through Time-variant Seismic Anisotropy Texas A&M University -...

  19. anisotropy probe wmap1: Topics by E-print Network

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

    Summary: The Wilkinson Microwave Anisotropy Probe (WMAP) mapped the distribution of temperature and polarization over the entire sky in five microwave frequency bands. These...

  20. anisotropy probe wmapobservations: Topics by E-print Network

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

    Summary: The Wilkinson Microwave Anisotropy Probe (WMAP) mapped the distribution of temperature and polarization over the entire sky in five microwave frequency bands. These...

  1. anisotropy probe 5-yr: Topics by E-print Network

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

    Summary: The Wilkinson Microwave Anisotropy Probe (WMAP) mapped the distribution of temperature and polarization over the entire sky in five microwave frequency bands. These...

  2. anisotropy instability thresholds: Topics by E-print Network

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

    these fluctuations are enhanced along the temperature anisotropy thresholds of the mirror, proton oblique firehose, and ion cyclotron instabilities. In addition, the measured...

  3. Resolution of reservoir scale electrical anisotropy from marine CSEM data

    E-Print Network [OSTI]

    Brown, V.

    2013-01-01T23:59:59.000Z

    the field data to accurately model potential reservoirs andreservoir scale electrical anisotropy from marine CSEM datathe reservoir target can be determined from seismic data or

  4. Concave nanomagnets with widely tunable anisotropy

    SciTech Connect (OSTI)

    Lambson, Brian; Gu, Zheng; Carlton, David; Bokor, Jeffrey

    2014-07-01T23:59:59.000Z

    A nanomagnet having widely tunable anisotropy is disclosed. The disclosed nanomagnet is a magnetic particle with a convex shape having a first magnetically easy axis. The convex shape is modified to include at least one concavity to urge a second magnetically easy axis to form substantially offset from the first magnetically easy axis. In at least one embodiment, the convex shape is also modified to include at least one concavity to urge a second magnetically easy axis to form with a magnetic strength substantially different from the first magnetically easy axis.

  5. Molecular anisotropy effects in carbon K-edge scattering: depolarized diffuse scattering and optical anisotropy

    SciTech Connect (OSTI)

    Stone, Kevin H.

    2014-07-14T23:59:59.000Z

    Some polymer properties, such as conductivity, are very sensitive to short- and intermediate-range orientational and positional ordering of anisotropic molecular functional groups, and yet means to characterize orientational order in disordered systems are very limited. We demonstrate that resonant scattering at the carbon K-edge is uniquely sensitive to short-range orientation correlations in polymers through depolarized scattering at high momentum transfers, using atactic polystyrene as a well-characterized test system. Depolarized scattering is found to coexist with unpolarized fluorescence, and to exhibit pronounced anisotropy. We also quantify the spatially averaged optical anisotropy from low-angle reflectivity measurements, finding anisotropy consistent with prior visible, x-ray absorption, and theoretical studies. The average anisotropy is much smaller than that in the depolarized scattering and the two have different character. Both measurements exhibit clear spectral signatures from the phenyl rings and the polyethylene-like backbone. Discussion focuses on analysis considerations and prospects for using this depolarized scattering for studies of disorder in soft condensed matter.

  6. Cosmic Microwave Background Anisotropy Window Functions Revisited

    E-Print Network [OSTI]

    Lloyd Knox

    1999-09-28T23:59:59.000Z

    The primary results of most observations of cosmic microwave background (CMB) anisotropy are estimates of the angular power spectrum averaged through some broad band, called band-powers. These estimates are in turn what are used to produce constraints on cosmological parameters due to all CMB observations. Essential to this estimation of cosmological parameters is the calculation of the expected band-power for a given experiment, given a theoretical power spectrum. Here we derive the "band power" window function which should be used for this calculation, and point out that it is not equivalent to the window function used to calculate the variance. This important distinction has been absent from much of the literature: the variance window function is often used as the band-power window function. We discuss the validity of this assumed equivalence, the role of window functions for experiments that constrain the power in {\\it multiple} bands, and summarize a prescription for reporting experimental results. The analysis methods detailed here are applied in a companion paper to three years of data from the Medium Scale Anisotropy Measurement.

  7. SUBMITTED TO GRL 1 Thermal Anisotropies in the Solar Wind

    E-Print Network [OSTI]

    Richardson, John

    SUBMITTED TO GRL 1 E Thermal Anisotropies in the Solar Wind: vidence of Heating by Interstellar cyclotron instabilit s generated by newly created pickup ions and heats the thermal solar wind protons TO GRL 2 T Introduction he thermal anisotropy of the solar wind is the ratio between the temperatures p

  8. ANNIVERSARY REVIEW Grain boundary energy anisotropy: a review

    E-Print Network [OSTI]

    Rohrer, Gregory S.

    energy (B) gained when the two surfaces are brought together and new bonds are formed. The grain boundaryANNIVERSARY REVIEW Grain boundary energy anisotropy: a review Gregory S. Rohrer Received: 29 April 2011 Abstract This paper reviews findings on the anisotropy of the grain boundary energies. After

  9. Anisotropy of strong pinning in multi-band superconductors

    E-Print Network [OSTI]

    Boyer, Edmond

    pinning in multi-band superconductors 2 1. Introduction The multi-band nature of superconductivity in iron the anisotropy of superconducting parameters in the iron-based superconductors. In particular, Kidzun et al. [23Anisotropy of strong pinning in multi-band superconductors C.J. van der Beek, M. Konczykowski

  10. Anisotropy of strong pinning in multi-band superconductors

    SciTech Connect (OSTI)

    van der Beek, C.J.; Konczykowski, M.; Prozorov, Ruslan

    2012-07-17T23:59:59.000Z

    The field-angular dependence and anisotropy of the critical current density in iron-based superconductors is evaluated using a phenomenological approach featuring distinct anisotropy factors for the penetration depth and the coherence length. Both the weak collective pinning limit and the strong pinning limit relevant for iron-based superconductors at low magnetic fields are considered. It is found that in the more anisotropic materials, such as SmFeAsO and NdFeAsO, the field-angular dependence is completely dominated by the coherence length (upper critical field) anisotropy, thereby explaining recent results on the critical current in these materials. In less anisotropic superconductors, strong pinning can lead to an apparent inversion of the anisotropy. Finally, it is shown that, under all circumstances, the ratio of the c-axis and ab-plane critical current densities for the magnetic field along the ab-plane directly yields the coherence length anisotropy factor ??.

  11. Mapping the nano-Hertz gravitational wave sky

    E-Print Network [OSTI]

    Neil J. Cornish; Rutger van Haasteren

    2014-06-19T23:59:59.000Z

    We describe a new method for extracting gravitational wave signals from pulsar timing data. We show that any gravitational wave signal can be decomposed into an orthogonal set of sky maps, with the number of maps equal to the number of pulsars in the timing array. These maps may be used as a basis to construct gravitational wave templates for any type of source, including collections of point sources. A variant of the standard Hellings-Downs correlation analysis is recovered for statistically isotropic signals. The template based approach allows us to probe potential anisotropies in the signal and produce maps of the gravitational wave sky.

  12. Rotation and anisotropy of galaxies revisited

    E-Print Network [OSTI]

    James Binney

    2005-04-18T23:59:59.000Z

    The use of the tensor virial theorem (TVT) as a diagnostic of anisotropic velocity distributions in galaxies is revisited. The TVT provides a rigorous global link between velocity anisotropy, rotation and shape, but the quantities appearing in it are not easily estimated observationally. Traditionally use has been made of a centrally averaged velocity dispersion and the peak rotation velocity. Although this procedure cannot be rigorously justified, tests on model galaxies show that it works surprisingly well. With the advent of integral-field spectroscopy it is now possible to establish a rigorous connection between the TVT and observations. The TVT is reformulated in terms of sky-averages, and the new formulation is tested on model galaxies.

  13. Relationship between Anisotropy in Soil Hydraulic Conductivity and Saturation

    SciTech Connect (OSTI)

    Zhang, Z. Fred

    2014-01-01T23:59:59.000Z

    Anisotropy in unsaturated hydraulic conductivity is saturation-dependent. Accurate characterization of soil anisotropy is very important in simulating flow and contaminant (e.g., radioactive nuclides in Hanford) transport. A recently developed tensorial connectivity-tortuosity (TCT) concept describes the hydraulic conductivity tensor of the unsaturated anisotropic soils as the product of a scalar variable, the symmetric connectivity tortuosity tensor, and the hydraulic conductivity tensor at saturation. In this study, the TCT model is used to quantify soil anisotropy in unsaturated hydraulic conductivity. The TCT model can describe different types of soil anisotropy; e.g., the anisotropy coefficient, C, can be monotonically increase or decrease with saturation and can vary from greater than unity to less than unity and vice versa. Soil anisotropy is independent of soil water retention properties and can be characterized by the ratio of the saturated hydraulic conductivities and the difference of the tortuosity-connectivity coefficients in two directions. ln(C) is linearly proportional to ln(Se) with Se being the effective saturation. The log-linear relationship between C and Se allows the saturation-dependent anisotropy to be determined using linear regression with the measurements of the directional hydraulic conductivities at a minimum of two water content levels, of which one may be at full saturation. The model was tested using measurements of directional hydraulic conductivities.

  14. Possible origin of the nonmonotonic doping dependence of the in-plane resistivity anisotropy of Ba(Fe1-xTx)?As? (T=Co, Ni and Cu)

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

    Kuo, Hsueh-Hui; Chu, Jiun-Haw; Riggs, Scott C.; Yu, Leo; McMahon, Peter L.; De Greve, Kristiaan; Yamamoto, Yoshihisa; Analytis, James G.; Fisher, Ian R.

    2011-08-01T23:59:59.000Z

    The in-plane resistivity anisotropy has been measured for detwinned single crystals of Ba(Fe1-xNix)?As? and Ba(Fe1-xCux)?As?. The data reveal a nonmonotonic doping dependence, similar to previous observations for Ba(Fe1-xCox)?As?. Magnetotransport measurements of the parent compound reveal a nonlinear Hall coefficient and a large linear term in the transverse magnetoresistance. Both effects are rapidly suppressed with chemical substitution over a similar compositional range as the onset of the large in-plane resistivity anisotropy. This suggests that the relatively small in-plane anisotropy of the parent compound in the spin-density wave state is due to the presence of an isotropic, high mobility pocket of the reconstructed Fermi surface. Progressive suppression of the contribution to the conductivity arising from this isotropic pocket with chemical substitution eventually reveals the underlying in-plane anisotropy associated with the remaining Fermi surface pockets

  15. anisotropy probe wmap: Topics by E-print Network

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

    in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the CMB anisotropy is the largest uncertainty. A...

  16. Current sheets and pressure anisotropy in the reconnection exhaust

    SciTech Connect (OSTI)

    Le, A.; Karimabadi, H.; Roytershteyn, V. [SciberQuest, Inc., Del Mar, California 92014 (United States)] [SciberQuest, Inc., Del Mar, California 92014 (United States); Egedal, J. [University of Wisconsin–Madison, Madison, Wisconsin 53706 (United States)] [University of Wisconsin–Madison, Madison, Wisconsin 53706 (United States); Ng, J. [PPPL, Princeton University, Princeton, New Jersey 08543 (United States)] [PPPL, Princeton University, Princeton, New Jersey 08543 (United States); Scudder, J. [University of Iowa, Iowa City, Iowa 52242 (United States)] [University of Iowa, Iowa City, Iowa 52242 (United States); Daughton, W.; Liu, Y.-H. [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

    2014-01-15T23:59:59.000Z

    A particle-in-cell simulation shows that the exhaust during anti-parallel reconnection in the collisionless regime contains a current sheet extending 100 inertial lengths from the X line. The current sheet is supported by electron pressure anisotropy near the X line and ion anisotropy farther downstream. Field-aligned electron currents flowing outside the magnetic separatrices feed the exhaust current sheet and generate the out-of-plane, or Hall, magnetic field. Existing models based on different mechanisms for each particle species provide good estimates for the levels of pressure anisotropy. The ion anisotropy, which is strong enough to reach the firehose instability threshold, is also important for overall force balance. It reduces the outflow speed of the plasma.

  17. Anisotropy and inhomogeneity of the universe from $?T/T$

    E-Print Network [OSTI]

    Roy Maartens; George Ellis; William Stoeger

    1995-10-24T23:59:59.000Z

    A recent paper (Martinez--Gonzalez & Sanz 1995) showed that if the universe is homogeneous but anisotropic, then the small quadrupole anisotropy in the cosmic microwave background radiation implies that the spacetime anisotropy is very small. We point out that more general results may be established, without assuming a priori homogeneity. We have proved that small anisotropies in the microwave background imply that the universe is almost Friedmann--Robertson--Walker. Furthermore, the quadrupole and octopole place direct and explicit limits on the degree of anisotropy and inhomogeneity, as measured by the shear, vorticity, Weyl tensor and density gradients. In the presence of inhomogeneity, it is only possible to set a much weaker limit on the shear than that given by Martinez--Gonzalez & Sanz.

  18. On the drift magnetosonic waves in anisotropic low beta plasmas

    SciTech Connect (OSTI)

    Naim, Hafsa, E-mail: roohi-phy@yahoo.com [Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Bashir, M. F., E-mail: frazbashir@yahoo.com [Department of Physics, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Murtaza, G. [Visiting Professor, Department of Physics, Quaid-e-Azam University, Islamabad (Pakistan)

    2014-10-15T23:59:59.000Z

    A generalized dispersion relation of obliquely propagating drift magnetosonic waves is derived by using the gyrokinetic theory for anisotropic low beta plasmas. The stability analysis applicable to a wide range of plasma parameters is performed to understand the stabilization mechanism of the drift magnetosonic instability and the estimation of the growth rate is also presented. It is noted that the growth rate of the drift instability enhances for small anisotropy (A{sub e,i}?=?T{sub ?e,i}/T{sub ?e,i}?anisotropy (A{sub e,i}?>?1)

  19. Colossal anisotropy of the magnetic properties of doped lithium nitrodometalates

    SciTech Connect (OSTI)

    Antropov, Vladimir P [Ames Laboratory; Antonov, Victor N [Ames Laboratory

    2014-09-01T23:59:59.000Z

    We present a first-principles investigation of the electronic structure and physical properties of doped lithium nitridometalates Li2(Li1?xMx)N (LiMN) with M = Cr, Mn, Fe, Co, and Ni. The diverse properties include the equilibrium magnetic moments, magneto-crystalline anisotropy, magneto-optical Kerr spectra, and x-ray magnetic circular dichroism. We explain the colossal magnetic anisotropy in LiFeN by its unique electronic structure which ultimately leads to a series of unusual physical properties. The most unique property is a complete suppression of relativistic effects and freezing of orbital moments for in-plane orientation of the magnetization. This leads to the colossal spatial anisotropy of many magnetic properties including energy, Kerr, and dichroism effects. LiFeN is identified as an ultimate single-ion anisotropy system where a nearly insulating state can be produced by a spin orbital coupling alone. A very nontrivial strongly fluctuating and sign changing character of the magnetic anisotropy with electronic 3d-atomic doping is predicted theoretically. A large and highly anisotropic Kerr effect due to the interband transitions between atomic-like Fe 3d bands is found for LiFeN. A giant anisotropy of the x-ray magnetic circular dichroism for the Fe K spectrum and a very weak one for the Fe L2,3 spectra in LiFeN are also predicted.

  20. Role of anisotropy configuration in exchange-biased systems.

    SciTech Connect (OSTI)

    Jimenez, E.; Camarero, J.; Perna, P.; Mikuszeit, N.; Teran, F. J.; Sort, J.; Nogues, J.; Garcia-Martin, J. M.; Hoffmann, A.; Dieny, B.; Miranda, R. (Materials Science Division); (Univ. Autonoma de Madrid); (Univ. Autonoma de Barcelona); (SPINTEC); (Inst. de Microelectronica de Madrid)

    2011-01-01T23:59:59.000Z

    We present a systematic study of the anisotropy configuration effects on the magnetic properties of exchange-biased ferromagnetic/antiferromagnetic (FM/AFM) Co/IrMn bilayers. The interfacial unidirectional anisotropy is set extrinsically via a field cooling procedure with the magnetic field misaligned by an angle {beta}{sub FC} with respect to the intrinsic FM uniaxial anisotropy. High resolution angular dependence in-plane resolved Kerr magnetometry measurements have been performed for three different anisotropy arrangements, including collinear {beta}{sub FC} = 0 and two opposite noncollinear cases. The symmetry breaking of the induced noncollinear configurations results in a peculiar nonsymmetric magnetic behavior of the angular dependence of magnetization reversal, coercivity, and exchange bias. The experimental results are well reproduced without any fitting parameter by using a simple model including the induced anisotropy configuration. Our finding highlights the importance of the relative angle between anisotropies in order to properly account for the magnetic properties of exchange-biased FM/AFM systems.

  1. Excitation of Banded Whistler Waves in the Magnetosphere

    SciTech Connect (OSTI)

    Gary, S. Peter [Los Alamos National Laboratory; Liu, Kaijun [Los Alamos National Laboratory; Winske, Dan [Los Alamos National Laboratory

    2012-07-13T23:59:59.000Z

    Banded whistler waves can be generated by the whistler anisotropy instability driven by two bi-Maxwellian electron components with T{sub {perpendicular}}/T{sub {parallel}} > 1 at different T{sub {parallel}} For typical magnetospheric condition of 1 < {omega}{sub e}/{Omega}{sub e} < 5 in regions associated with strong chorus, upper-band waves can be excited by anisotropic electrons below {approx} 1 keV, while lower-band waves are excited by anisotropic electrons above {approx} 10 keV. Lower-band waves are generally field-aligned and substantially electromagnetic, while upper-band waves propagate obliquely and have quasi-electrostatic fluctuating electric fields. The quasi-electrostatic feature of upper-band waves suggests that they may be more easily identified in electric field observations than in magnetic field observations. Upper-band waves are liable to Landau damping and the saturation level of upperband waves is lower than lower-band waves, consistent with observations that lower-band waves are stronger than upper-band waves on average. The oblique propagation, the lower saturation level, and the more severe Landau damping together would make upper-band waves more tightly confined to the geomagnetic equator (|{lambda}{sub m}| < {approx}10{sup o}) than lower-band waves.

  2. Correlated Detection of sub-mHz Gravitational Waves by Two Optical-Fiber Interferometers

    E-Print Network [OSTI]

    Reginald T Cahill; Finn Stokes

    2008-02-18T23:59:59.000Z

    Results from two optical-fiber gravitational-wave interferometric detectors are reported. The detector design is very small, cheap and simple to build and operate. Using two detectors has permitted various tests of the design principles as well as demonstrating the first simultaneous detection of correlated gravitational waves from detectors spatially separated by 1.1km. The frequency spectrum of the detected gravitational waves is sub-mHz with a strain spectral index a=-1.4 +/- 0.1. As well as characterising the wave effects the detectors also show, from data collected over some 80 days in the latter part of 2007, the dominant earth rotation effect and the earth orbit effect. The detectors operate by exploiting light speed anisotropy in optical-fibers. The data confirms previous observations of light speed anisotropy, earth rotation and orbit effects, and gravitational waves.

  3. Magnetic instability in a dilute circular rarefaction wave

    SciTech Connect (OSTI)

    Dieckmann, M. E. [Department of Science and Technology (ITN), Linkoping University, 60174 Norrkoping (Sweden); Sarri, G.; Borghesi, M. [Centre for Plasma Physics, School of Mathematics and Physics, Queen's University of Belfast, Belfast BT7 1NN (United Kingdom)

    2012-12-15T23:59:59.000Z

    The growth of magnetic fields in the density gradient of a rarefaction wave has been observed in simulations and in laboratory experiments. The thermal anisotropy of the electrons, which gives rise to the magnetic instability, is maintained by the ambipolar electric field. This simple mechanism could be important for the magnetic field amplification in astrophysical jets or in the interstellar medium ahead of supernova remnant shocks. The acceleration of protons and the generation of a magnetic field by the rarefaction wave, which is fed by an expanding circular plasma cloud, is examined here in form of a 2D particle-in-cell simulation. The core of the plasma cloud is modeled by immobile charges, and the mobile protons form a small ring close to the cloud's surface. The number density of mobile protons is thus less than that of the electrons. The protons of the rarefaction wave are accelerated to 1/10 of the electron thermal speed, and the acceleration results in a thermal anisotropy of the electron distribution in the entire plasma cloud. The instability in the rarefaction wave is outrun by a TM wave, which grows in the dense core distribution, and its magnetic field expands into the rarefaction wave. This expansion drives a secondary TE wave.

  4. Macroscopic model with anisotropy based on micro-macro informations

    E-Print Network [OSTI]

    Nishant Kumar; Stefan Luding; Vanessa Magnanimo

    2015-06-15T23:59:59.000Z

    Physical experiments can characterize the elastic response of granular materials in terms of macroscopic state-variables, namely volume (packing) fraction and stress, while the microstructure is not accessible and thus neglected. Here, by means of numerical simulations, we analyze dense, frictionless, granular assemblies with the final goal to relate the elastic moduli to the fabric state, i.e., to micro-structural averaged contact network features as contact number density and anisotropy. The particle samples are first isotropically compressed and later quasi-statically sheared under constant volume (undrained conditions). From various static, relaxed configurations at different shear strains, now infinitesimal strain steps are applied to "measure" the effective elastic response; we quantify the strain needed so that plasticity in the sample develops as soon as contact and structure rearrangements happen. Because of the anisotropy induced by shear, volumetric and deviatoric stresses and strains are cross-coupled via a single anisotropy modulus, which is proportional to the product of deviatoric fabric and bulk modulus (i.e. the isotropic fabric). Interestingly, the shear modulus of the material depends also on the actual stress state, along with the contact configuration anisotropy. Finally, a constitutive model based on incremental evolution equations for stress and fabric is introduced. By using the previously measured dependence of the stiffness tensor (elastic moduli) on the microstructure, the theory is able to predict with good agreement the evolution of pressure, shear stress and deviatoric fabric (anisotropy) for an independent undrained cyclic shear test, including the response to reversal of strain.

  5. Plastic anisotropy in a superplastic duplex stainless steel

    SciTech Connect (OSTI)

    Song, J.L.; Bate, P.S. [Univ. of Birmingham (United Kingdom)] [Univ. of Birmingham (United Kingdom)

    1997-07-01T23:59:59.000Z

    Measurements of the plastic anisotropy in uniaxial tension of the duplex stainless steel, SAF2304, have been made at room temperature and under conditions where the material was superplastic. There was significant plastic anisotropy in both types of deformation and there were some similarities between the low and high temperature variations with tensile axis orientation. Although it was possible to model the high temperature anisotropy using a grain boundary sliding model, the assumed distribution of sliding boundaries was considered to be unrealistic. This, together with aspects of microstructural and textural development, indicated that deformation was principally occurring by intragranular slip with a significant contribution caused by mechanical inhomogeneity in the two-phase material.

  6. SIMULTANEOUS MEASUREMENT OF CIRCULAR DICHROISM AND FLUORESCENCE POLARIZATION ANISOTROPY.

    SciTech Connect (OSTI)

    SUTHERLAND,J.C.

    2002-01-19T23:59:59.000Z

    Circular dichroism and fluorescence polarization anisotropy are important tools for characterizing biomolecular systems. Both are used extensively in kinetic experiments involving stopped- or continuous flow systems as well as titrations and steady-state spectroscopy. This paper presents the theory for determining circular dichroism and fluorescence polarization anisotropy simultaneously, thus insuring the two parameters are recorded under exactly the same conditions and at exactly the same time in kinetic experiments. The approach to measuring circular dichroism is that used in almost all conventional dichrographs. Two arrangements for measuring fluorescence polarization anisotropy are described. One uses a single fluorescence detector and signal processing with a lock-in amplifier that is similar to the measurement of circular dichroism. The second approach uses classic ''T'' format detection optics, and thus can be used with conventional photon-counting detection electronics. Simple extensions permit the simultaneous measurement of the absorption and excitation intensity corrected fluorescence intensity.

  7. Predicted Impacts of Proton Temperature Anisotropy on Solar Wind Turbulence

    E-Print Network [OSTI]

    Klein, Kristopher G

    2015-01-01T23:59:59.000Z

    Particle velocity distributions measured in the weakly collisional solar wind are frequently found to be non-Maxwellian, but how these non-Maxwellian distributions impact the physics of plasma turbulence in the solar wind remains unanswered. Using numerical solutions of the linear dispersion relation for a collisionless plasma with a bi-Maxwellian proton velocity distribution, we present a unified framework for the four proton temperature anisotropy instabilities, identifying the associated stable eigenmodes, highlighting the unstable region of wavevector space, and presenting the properties of the growing eigenfunctions. Based on physical intuition gained from this framework, we address how the proton temperature anisotropy impacts the nonlinear dynamics of the \\Alfvenic fluctuations underlying the dominant cascade of energy from large to small scales and how the fluctuations driven by proton temperature anisotropy instabilities interact nonlinearly with each other and with the fluctuations of the large-scal...

  8. Vacuum Waves

    E-Print Network [OSTI]

    Paul S. Wesson

    2012-12-11T23:59:59.000Z

    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.

  9. Enhancing Magnetic Properties of Molecular Magnetic Materials: The Role of Single-Ion Anisotropy

    E-Print Network [OSTI]

    Saber, Mohamed Rashad Mohamed

    2013-07-09T23:59:59.000Z

    trend in the field is enhancing the global anisotropy in metal complexes using single-ion anisotropy. The work in this dissertation is devoted to the synthesis and characterization of new building blocks of the highly anisotropic early transition metal...

  10. Analysis of seismic anisotropy in 3D multi-component seismic data 

    E-Print Network [OSTI]

    Qian, Zhongping

    2010-01-01T23:59:59.000Z

    The importance of seismic anisotropy has been recognized by the oil industry since its first observation in hydrocarbon reservoirs in 1986, and the application of seismic anisotropy to solve geophysical problems has been ...

  11. Seismic waves in rocks with fluids and fractures

    SciTech Connect (OSTI)

    Berryman, J.G.

    2007-05-14T23:59:59.000Z

    Seismic wave propagation through the earth is often stronglyaffected by the presence of fractures. When these fractures are filledwith fluids (oil, gas, water, CO2, etc.), the type and state of the fluid(liquid or gas) can make a large difference in the response of theseismic waves. This paper summarizes recent work on methods ofdeconstructing the effects of fractures, and any fluids within thesefractures, on seismic wave propagation as observed in reflection seismicdata. One method explored here is Thomsen's weak anisotropy approximationfor wave moveout (since fractures often induce elastic anisotropy due tononuniform crack-orientation statistics). Another method makes use ofsome very convenient fracture parameters introduced previously thatpermit a relatively simple deconstruction of the elastic and wavepropagation behavior in terms of a small number of fracture parameters(whenever this is appropriate, as is certainly the case for small crackdensities). Then, the quantitative effects of fluids on thesecrack-influence parameters are shown to be directly related to Skempton scoefficient B of undrained poroelasticity (where B typically ranges from0 to 1). In particular, the rigorous result obtained for the low crackdensity limit is that the crack-influence parameters are multiplied by afactor (1 ? B) for undrained systems. It is also shown how fractureanisotropy affects Rayleigh wave speed, and how measured Rayleigh wavespeeds can be used to infer shear wave speed of the fractured medium.Higher crack density results are also presented by incorporating recentsimulation data on such cracked systems.

  12. Anisotropic wave propagation in nematic liquid crystals

    E-Print Network [OSTI]

    Paolo Biscari; Antonio DiCarlo; Stefano S. Turzi

    2014-05-10T23:59:59.000Z

    Despite the fact that quantitative experimental data have been available for more than forty years now, nematoacoustics still poses intriguing theoretical and experimental problems. In this paper, we prove that the main observed features of acoustic wave propagation through a nematic liquid crystal cell -- namely, the anisotropy of sound velocity and its frequency dependence -- may be plausibly explained by a first-gradient continuum theory characterized by a hyperelastic anisotropic response from an evolving relaxed configuration. We compare and contrast our proposal with a competing theory where the liquid crystal is modeled as an isotropically compressible, anisotropic second-gradient fluid.

  13. Interpretation of seismic anisotropy in terms of mantle flow when melt is present

    E-Print Network [OSTI]

    Kaminski, Edouard

    Interpretation of seismic anisotropy in terms of mantle flow when melt is present E. Kaminski scale. Citation: Kaminski, E. (2006), Interpretation of seismic anisotropy in terms of mantle flow when of seismic anisotropy to image upper mantle flow is usually based on the assumption that the direction

  14. ANISOTROPY LENGTHENS THE DECAY TIME OF TURBULENCE IN MOLECULAR CLOUDS

    SciTech Connect (OSTI)

    Hansen, Charles E.; McKee, Christopher F.; Klein, Richard I. [Astronomy Department, University of California, Berkeley, CA 94720 (United States)

    2011-09-01T23:59:59.000Z

    The decay of isothermal turbulence with velocity anisotropy is investigated using computational simulations and synthetic observations. We decompose the turbulence into isotropic and anisotropic components with total velocity dispersions {sigma}{sub iso} and {sigma}{sub ani}, respectively. We find that the decay rate of the turbulence depends on the crossing time of the isotropic component only. A cloud of size L with significant anisotropy in its turbulence has a dissipation time, t{sub diss} = L/(2{sigma}{sub iso}). This translates into turbulent energy decay rates on the cloud scale that can be much lower for anisotropic turbulence than for isotropic turbulence. To help future observations determine whether observed molecular clouds have the level of anisotropy required to maintain the observed level of turbulence over their lifetimes, we performed a principal component analysis on our simulated clouds. Even with projection effects washing out the anisotropic signal, there is a measurable difference in the axis-constrained principal component analysis performed in directions parallel and perpendicular to the direction of maximum velocity dispersion. When this relative difference, {psi}, is 0.1, there is enough anisotropy for the dissipation time to triple the expected isotropic value. We provide a fit for converting {psi} into an estimate for the dissipation time, t{sub diss}.

  15. Vitrinite reflectance anisotropy as a tectonic fabric element

    SciTech Connect (OSTI)

    Hower, J.C. (Univ. of Kentucky, Lexington); Davis, A.

    1981-04-01T23:59:59.000Z

    The anisotropy of the coal maceral vitrinite was analyzed in relation to the tectonic setting of a coal from the Southern Anthracite Field in Pennsylvania. For the coal studied, the maximum-intermediate reflectance plane essentially paralleled the axial plane of the synclinorium (N66/sup 0/E strike, 64/sup 0/SE dip).

  16. anisotropy energy spectrum: Topics by E-print Network

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

    anisotropy energy spectrum First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Ultra High Energy Cosmic...

  17. Anisotropy of strong pinning in multi-band superconductors

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    Anisotropy of strong pinning in multi-band superconductors C.J. van der Beek, M. Konczykowski of the critical current density in iron-based superconductors is evaluated using a phenomenological approach collective pinning limit, and the strong pinning limit relevant for iron-based superconductors at low

  18. Resolution of reservoir scale electrical anisotropy from marine CSEM data

    SciTech Connect (OSTI)

    Brown, V.; Hoversten, G.M.; Key, K.; Chen, J.

    2011-10-01T23:59:59.000Z

    A combination of 1D and 3D forward and inverse solutions is used to quantify the sensitivity and resolution of conventional controlled source electromagnetic (CSEM) data collected using a horizontal electric dipole source to transverse electrical anisotropy located in a deep-water exploration reservoir target. Since strongly anisotropic shale layers have a vertical resistivity that can be comparable to many reservoirs, we examine how CSEM can discriminate confounding shale layers through their characteristically lower horizontal resistivity. Forward modeling demonstrates that the sensitivity to reservoir level anisotropy is very low compared to the sensitivity to isotropic reservoirs, especially when the reservoir is deeper than about 2 km below the seabed. However, for 1D models where the number of inversion parameters can be fixed to be only a few layers, both vertical and horizontal resistivity of the reservoir can be well resolved using a stochastic inversion. We find that the resolution of horizontal resistivity increases as the horizontal resistivity decreases. We show that this effect is explained by the presence of strong horizontal current density in anisotropic layers with low horizontal resistivity. Conversely, when the reservoir has a vertical to horizontal resistivity ratio of about 10 or less, the current density is vertically polarized and hence has little sensitivity to the horizontal resistivity. Resistivity anisotropy estimates from 3D inversion for 3D targets suggest that resolution of reservoir level anisotropy for 3D targets will require good a priori knowledge of the background sediment conductivity and structural boundaries.

  19. ANISOTROPY OF SOURCE PARAMETERS FROM INDUCED MICROSEISMICITY Peter Starzec1

    E-Print Network [OSTI]

    1 ANISOTROPY OF SOURCE PARAMETERS FROM INDUCED MICROSEISMICITY Peter Starzec1 , Michael Fehler2 distributions of shear displacement at the source of microearthquakes induced by hydraulic fracturing were the reservoir that are far from injection wells. Background The Hot Dry Rock Geothermal Energy (HDR) concept

  20. Spin wave localization in one-dimensional magnonic microcavity comprising yttrium iron garnet

    SciTech Connect (OSTI)

    Kanazawa, Naoki; Goto, Taichi, E-mail: goto@ee.tut.ac.jp; Inoue, Mitsuteru [Department of Electrical and Electronic Information Engineering, Toyohashi University of Technology, 1-1 Hibari-Ga-Oka, Tempaku, Toyohashi, Aichi 441-8580 (Japan)

    2014-08-28T23:59:59.000Z

    We demonstrate the localization of magnetostatic surface waves, i.e., spin waves, in a one-dimensional magnonic microcavity substantialized with periodical conductivity modulation. The narrow localized state is observed inside band gaps and is responsible for a sharp transmission peak. The experimental results strongly agree with the theoretical prediction made with the shape magnetic anisotropy of the propagating medium composed of yttrium iron garnet taken into account.

  1. Wave represents displacement Wave represents pressure Source -Sound Waves

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    Wave represents displacement Wave represents pressure Source - Sound Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency

  2. Gravitational wave radiometry: Mapping a stochastic gravitational wave background

    SciTech Connect (OSTI)

    Mitra, Sanjit [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Observatoire de la Cote d'Azur, BP 4229, 06304 Nice Cedex 4 (France); Dhurandhar, Sanjeev; Souradeep, Tarun [Inter-University Centre for Astronomy and Astrophysics, Post Bag 4, Ganeshkhind, Pune 411007 (India); Lazzarini, Albert; Mandic, Vuk; Ballmer, Stefan [LIGO Laboratory, California Institute of Technology, MS 18-34, Pasadena, California 91125 (United States); Bose, Sukanta [Department of Physics, Washington State University, Pullman, Washington 99164-2814 (United States)

    2008-02-15T23:59:59.000Z

    The problem of the detection and mapping of a stochastic gravitational wave background (SGWB), either cosmological or astrophysical, bears a strong semblance to the analysis of the cosmic microwave background (CMB) anisotropy and polarization, which too is a stochastic field, statistically described in terms of its correlation properties. An astrophysical gravitational wave background (AGWB) will likely arise from an incoherent superposition of unmodelled and/or unresolved sources and cosmological gravitational wave backgrounds (CGWB) are also predicted in certain scenarios. The basic statistic we use is the cross correlation between the data from a pair of detectors. In order to ''point'' the pair of detectors at different locations one must suitably delay the signal by the amount it takes for the gravitational waves (GW) to travel to both detectors corresponding to a source direction. Then the raw (observed) sky map of the SGWB is the signal convolved with a beam response function that varies with location in the sky. We first present a thorough analytic understanding of the structure of the beam response function using an analytic approach employing the stationary phase approximation. The true sky map is obtained by numerically deconvolving the beam function in the integral (convolution) equation. We adopt the maximum likelihood framework to estimate the true sky map using the conjugate gradient method that has been successfully used in the broadly similar, well-studied CMB map-making problem. We numerically implement and demonstrate the method on signal generated by simulated (unpolarized) SGWB for the GW radiometer consisting of the LIGO pair of detectors at Hanford and Livingston. We include 'realistic' additive Gaussian noise in each data stream based on the LIGO-I noise power spectral density. The extension of the method to multiple baselines and polarized GWB is outlined. In the near future the network of GW detectors, including the Advanced LIGO and Virgo detectors that will be sensitive to sources within a thousand times larger spatial volume, could provide promising data sets for GW radiometry.

  3. Seismic velocity and Q anisotropy in fractured poroelastic media

    E-Print Network [OSTI]

    Introduction. Seismic wave propagation through fractures is an important subject in hydrocarbon exploration geophysics, mining and reservoir characterization ...

  4. FIVE-YEAR WILKINSON MICROWAVE ANISOTROPY PROBE OBSERVATIONS: SOURCE CATALOG

    SciTech Connect (OSTI)

    Wright, E. L.; Chen, X. [UCLA Physics and Astronomy, P.O. Box 951547, Los Angeles, CA 90095-1547 (United States); Odegard, N.; Hill, R. S.; Weiland, J. L. [Adnet Systems, Inc., 7515 Mission Dr., Suite A100, Lanham, MD 20706 (United States); Bennett, C. L.; Gold, B.; Larson, D. [Department of Physics and Astronomy, Johns Hopkins University, 3400 N. Charles St., Baltimore, MD 21218-2686 (United States); Hinshaw, G.; Wollack, E.; Kogut, A. [Code 665, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Jarosik, N.; Page, L.; Dunkley, J. [Department of Physics, Jadwin Hall, Princeton University, Princeton, NJ 08544-0708 (United States); Komatsu, E. [Department of Astronomy, University of Texas, Austin, 2511 Speedway, RLM 15.306, Austin, TX 78712 (United States); Nolta, M. R. [Canadian Institute for Theoretical Astrophysics, University of Toronto, 60 St. George St., Toronto, ON M5S 3H8 (Canada); Spergel, D. N. [Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544-1001 (United States); Halpern, M. [Department of Physics and Astronomy, University of British Columbia, Vancouver, BC V6T 1Z1 (Canada); Limon, M. [Columbia Astrophysics Laboratory, 550 W. 120th St., Mail Code 5247, New York, NY 10027-6902 (United States); Meyer, S. S. [Departments of Astrophysics and Physics, KICP and EFI, University of Chicago, Chicago, IL 60637 (United States)], E-mail: wright@astro.ucla.edu (and others)

    2009-02-15T23:59:59.000Z

    We present the list of point sources found in the Wilkinson Microwave Anisotropy Probe (WMAP) five-year maps. The technique used in the first-year and three-year analyses now finds 390 point sources, and the five-year source catalog is complete for regions of the sky away from the Galactic plane to a 2 Jy limit, with SNR >4.7 in all bands in the least covered parts of the sky. The noise at high frequencies is still mainly radiometer noise, but at low frequencies the cosmic microwave background (CMB) anisotropy is the largest uncertainty. A separate search of CMB-free V-W maps finds 99 sources of which all but one can be identified with known radio sources. The sources seen by WMAP are not strongly polarized. Many of the WMAP sources show significant variability from year to year, with more than a 2:1 range between the minimum and maximum fluxes.

  5. Anisotropies in magnetic field evolution and local Lyapunov exponents

    SciTech Connect (OSTI)

    Tang, X.Z.; Boozer, A.H.

    2000-01-13T23:59:59.000Z

    The natural occurrence of small scale structures and the extreme anisotropy in the evolution of a magnetic field embedded in a conducting flow is interpreted in terms of the properties of the local Lyapunov exponents along the various local characteristic (un)stable directions for the Lagrangian flow trajectories. The local Lyapunov exponents and the characteristic directions are functions of Lagrangian coordinates and time, which are completely determined once the flow field is specified. The characteristic directions that are associated with the spatial anisotropy of the problem, are prescribed in both Lagrangian and Eulerian frames. Coordinate transformation techniques are employed to relate the spatial distributions of the magnetic field, the induced current density, and the Lorentz force, which are usually followed in Eulerian frame, to those of the local Lyapunov exponents, which are naturally defined in Lagrangian coordinates.

  6. Anisotropies in magnetic field evolution and local Lyapunov exponents

    SciTech Connect (OSTI)

    Tang, X. Z. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)] [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Boozer, A. H. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)] [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)

    2000-04-01T23:59:59.000Z

    The natural occurrence of small scale structures and the extreme anisotropy in the evolution of a magnetic field embedded in a conducting flow is interpreted in terms of the properties of the local Lyapunov exponents along the various local characteristic (un)stable directions for the Lagrangian flow trajectories. The local Lyapunov exponents and the characteristic directions are functions of Lagrangian coordinates and time, which are completely determined once the flow field is specified. The characteristic directions that are associated with the spatial anisotropy of the problem, are prescribed in both Lagrangian and Eulerian frames. Coordinate transformation techniques are employed to relate the spatial distributions of the magnetic field, the induced current density, and the Lorentz force, which are usually followed in Eulerian frame, to those of the local Lyapunov exponents, which are naturally defined in Lagrangian coordinates. (c) 2000 American Institute of Physics.

  7. Q-anisotropy of qP waves in finely-layered media

    E-Print Network [OSTI]

    2009-05-05T23:59:59.000Z

    1Istituto Nazionale di Oceanografia e di Geofisica Sperimentale (OGS). Borgo Grotta Gigante 42c, 34010 Sgonico, Trieste, Italy. Tel: 0039-40-2140345, Fax: +

  8. P wave anisotropy, stress, and crack distribution at Coso geothermal field,

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to: navigation, searchOfRoseConcernsCompany OilInformationPre-TaxShelfOxfordValleyCalifornia

  9. Azimuthal anisotropy distributions in high-energy collisions

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

    Yan, Li; Ollitrault, Jean-Yves; Poskanzer, Arthur M.

    2015-03-01T23:59:59.000Z

    Elliptic flow in ultrarelativistic heavy-ion collisions results from the hydrodynamic response to the spatial anisotropy of the initial density profile. Along-standing problem in the interpretation of flow data is that uncertainties in the initial anisotropy are mingled with uncertainties in the response. We argue that the non-Gaussianity of flow fluctuations in small systems with large fluctuations can be used to disentangle the initial state from the response. We apply this method to recent measurements of anisotropic flow in Pb+Pb and p+Pb collisions at the LHC, assuming linear response to the initial anisotropy. The response coefficient is found to decrease asmore »the system becomes smaller and is consistent with a low value of the ratio of viscosity over entropy of ?/s 0.19. Deviations from linear response are studied. While they significantly change the value of the response coefficient they do not change the rate of decrease with centrality. Thus, we argue that the estimate of ?/s is robust against non-linear effects.« less

  10. Exchange coupling between silicon donors: the crucial role of the central cell and mass anisotropy

    E-Print Network [OSTI]

    G. Pica; B. W. Lovett; R. N Bhatt; S. A. Lyon

    2014-07-08T23:59:59.000Z

    Donors in silicon are now demonstrated as one of the leading candidates for implementing qubits and quantum information processing. Single qubit operations, measurements and long coherence times are firmly established, but progress on controlling two qubit interactions has been slower. One reason for this is that the inter donor exchange coupling has been predicted to oscillate with separation, making it hard to estimate in device designs. We present a multivalley effective mass theory of a donor pair in silicon, including both a central cell potential and the effective mass anisotropy intrinsic in the Si conduction band. We are able to accurately describe the single donor properties of valley-orbit coupling and the spatial extent of donor wave functions, highlighting the importance of fitting measured values of hyperfine coupling and the orbital energy of the $1s$ levels. Ours is a simple framework that can be applied flexibly to a range of experimental scenarios, but it is nonetheless able to provide fast and reliable predictions. We use it to estimate the exchange coupling between two donor electrons and we find a smoothing of its expected oscillations, and predict a monotonic dependence on separation if two donors are spaced precisely along the [100] direction.

  11. Resolving Spacecraft Earth-Flyby Anomalies with Measured Light Speed Anisotropy

    E-Print Network [OSTI]

    Reginald T. Cahill

    2008-04-30T23:59:59.000Z

    Doppler shift observations of spacecraft, such as Galileo, NEAR, Cassini, Rosetta and MESSENGER in earth flybys, have all revealed unexplained speed `anomalies' - that the doppler-shift determined speeds are inconsistent with expected speeds. Here it is shown that these speed anomalies are not real and are actually the result of using an incorrect relationship between the observed doppler shift and the speed of the spacecraft - a relationship based on the assumption that the speed of light is isotropic in all frames, i.e. invariant. Taking account of the repeatedly measured light-speed anisotropy the anomalies are resolved. The Pioneer 10/11 anomalies are discussed, but not resolved. The spacecraft observations demonstrate again that the speed of light is not invariant, and is isotropic only with respect to a dynamical 3-space. The existing doppler shift data also offers a resource to characterise a new form of gravitational waves, the dynamical 3-space turbulence, that has also been detected by other techniques.

  12. CALCUL QUANTIQUE DE L'ANISOTROPIE DIAMAGNTIQUE DES MOLCULES ORGANIQUES III. HYDROCARBURES AROMATIQUES COMPLEXES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    15. CALCUL QUANTIQUE DE L'ANISOTROPIE DIAMAGNÉTIQUE DES MOLÉCULES ORGANIQUES III. HYDROCARBURES orbitales moléculaires est étendue au cas des hydrocarbures conjugués contenant au moins quatre noyaux

  13. anisotropy probe five-year: Topics by E-print Network

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

    Summary: The Wilkinson Microwave Anisotropy Probe (WMAP) mapped the distribution of temperature and polarization over the entire sky in five microwave frequency bands. These...

  14. Graphene Signal Amplification for Sensitive and Real-Time Fluorescence Anisotropy Detection of Small Molecules

    E-Print Network [OSTI]

    Tan, Weihong

    Graphene Signal Amplification for Sensitive and Real-Time Fluorescence Anisotropy Detection graphene oxide (GO) as the signal amplifier. Because of the extraordinarily larger volume of GO

  15. Synchrotron X-ray Applications Toward an Understanding of Elastic Anisotropy

    E-Print Network [OSTI]

    Kanitpanyacharoen, Waruntorn

    2012-01-01T23:59:59.000Z

    anisotropy of hydrocarbon source rock. Geophysics, 57, 727-of hydrocarbons in Toarcian source rocks of differentDeposition of petroleum source rocks. In: Welte, D.H. ,

  16. 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

  17. Multi-region relaxed magnetohydrodynamics with anisotropy and flow

    SciTech Connect (OSTI)

    Dennis, G. R., E-mail: graham.dennis@anu.edu.au; Dewar, R. L.; Hole, M. J. [Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Hudson, S. R. [Princeton Plasma Physics Laboratory, PO Box 451, Princeton, New Jersey 08543 (United States)

    2014-07-15T23:59:59.000Z

    We present an extension of the multi-region relaxed magnetohydrodynamics (MRxMHD) equilibrium model that includes pressure anisotropy and general plasma flows. This anisotropic extension to our previous isotropic model is motivated by Sun and Finn's model of relaxed anisotropic magnetohydrodynamic equilibria. We prove that as the number of plasma regions becomes infinite, our anisotropic extension of MRxMHD reduces to anisotropic ideal MHD with flow. The continuously nested flux surface limit of our MRxMHD model is the first variational principle for anisotropic plasma equilibria with general flow fields.

  18. Large-Scale Anisotropy of EGRET Gamma Ray Sources

    E-Print Network [OSTI]

    Luis Anchordoqui; Thomas McCauley; Thomas Paul; Olaf Reimer; Diego F. Torres

    2005-06-24T23:59:59.000Z

    In the course of its operation, the EGRET experiment detected high-energy gamma ray sources at energies above 100 MeV over the whole sky. In this communication, we search for large-scale anisotropy patterns among the catalogued EGRET sources using an expansion in spherical harmonics, accounting for EGRET's highly non-uniform exposure. We find significant excess in the quadrupole and octopole moments. This is consistent with the hypothesis that, in addition to the galactic plane, a second mid-latitude (5^{\\circ} < |b| < 30^{\\circ}) population, perhaps associated with the Gould belt, contributes to the gamma ray flux above 100 MeV.

  19. Effect of radiation-like solid on CMB anisotropies

    E-Print Network [OSTI]

    Vladimír Balek; Matej Škovran

    2015-01-28T23:59:59.000Z

    We compute the power in the lowest multipoles of CMB anisotropies in the presence of radiation-like solid, a hypothetical new kind of radiation with nonzero shear modulus. If only the ordinary Sachs-Wolfe effect is taken into account, the shear modulus to energy density ratio must be in absolute value of order $10^{-5}$ or less for the theory to be consistent with observations within cosmic variance. With the integrated Sachs-Wolfe effect switched on, the constraint is relaxed almost by two orders of magnitude.

  20. Elastic anisotropy in multifilament Nb3Sn superconducting wires

    E-Print Network [OSTI]

    Scheuerlein, C; Alknes, P; Arnau, G; Bjoerstad, R; Bordini, B

    2015-01-01T23:59:59.000Z

    The elastic anisotropy caused by the texture in the Nb3Sn filaments of PIT and RRP wires has been calculated by averaging the estimates of Voigt and Reuss, using published Nb3Sn single crystal elastic constants and the Nb3Sn grain orientation distribution determined in both wire types by Electron Backscatter Diffraction. At ambient temperature the calculated Nb3Sn E-moduli in axial direction in the PIT and the RRP wire are 130 GPa and 140 GPa, respectively. The calculated E-moduli are compared with tensile test results obtained for the corresponding wires and extracted filament bundles.

  1. Distribution Function of Dark Matter with Constant Anisotropy

    E-Print Network [OSTI]

    Ding Ma; Ping He

    2008-08-01T23:59:59.000Z

    N-body simulations of dark matter halos show that the density is cusped near the center of the halo. The density profile behaves as $r^{-\\gamma}$ in the inner parts, where $\\gamma \\simeq 1$ for the NFW model and $\\gamma \\simeq 1.5$ for the Moore's model, but in the outer parts, both models agree with each other in the asymptotic behavior of the density profile. The simulations also show the information about anisotropy parameter $\\beta(r)$ of velocity distribution. $\\beta\\approx 0$ in the inner part and $\\beta\\approx 0.5$ (radially anisotropic) in the outer part of the halo. We provide some distribution functions $F(E,L)$ with the constant anisotropy parameter $\\beta$ for the two spherical models of dark matter halos: a new generalized NFW model and a generalized Moore model. There are two parameters $\\alpha$ and $\\epsilon$ for those two generalized models to determine the asymptotic behavior of the density profile. In this paper, we concentrate on the situation of $\\beta(r)=1/2$ from the viewpoint of the simulation.

  2. Optical Anisotropy of Schwarzschild Metric within Equivalent Medium Framework

    E-Print Network [OSTI]

    Sina Khorasani; Bizhan Rashidian

    2009-12-16T23:59:59.000Z

    It is has been long known that the curved space in the presence of gravitation can be described as a non-homogeneous anisotropic medium in flat geometry with different constitutive equations. In this article, we show that the eigenpolarizations of such medium can be exactly solved, leading to a pseudo-isotropic description of curved vacuum with two refractive index eigenvalues having opposite signs, which correspond to forward and backward travel in time. We conclude that for a rotating universe, time-reversal symmetry is broken. We also demonstrate the applicability of this method to Schwarzschild metric and derive exact forms of refractive index. We derive the subtle optical anisotropy of space around a spherically symmetric, non-rotating and uncharged blackhole in the form of an elegant closed form expression, and show that the refractive index in such a pseudo-isotropic system would be a function of coordinates as well as the direction of propagation. Corrections arising from such anisotropy in the bending of light are shown and a simplified system of equations for ray-tracing in the equivalent medium of Schwarzschild metric is found.

  3. Azimuthal anisotropy in U+U collisions at STAR

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

    Wang, Hui; Sorensen, Paul

    2014-12-01T23:59:59.000Z

    The azimuthal anisotropy of particle production is commonly used in high-energy nuclear collisions to study the early evolution of the expanding system. The prolate shape of uranium nuclei makes it possible to study how the geometry of the colliding nuclei affects #12;final state anisotropies. It also provides a unique opportunity to understand how entropy is produced in heavy ion collisions. In this paper, the two- and four- particle cumulant v2 (v2{2} and v2{4}) from U+U collisions at ?sNN = 193 GeV and Au+Au collisions at ?sNN = 200 GeV for inclusive charged hadrons will be presented. The STAR Zero Degreemore »Calorimeters are used to select very central collisions. Differences were observed between the multiplicity dependence of v2{2} for most central Au+Au and U+U collisions. The multiplicity dependence of v2{2} in central collisions were compared to Monte Carlo Glauber model predictions and it was seen that this model cannot explain the present results. (auth)« less

  4. Azimuthal anisotropy in U+U collisions at STAR

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

    Wang, Hui; Sorensen, Paul

    2014-12-01T23:59:59.000Z

    The azimuthal anisotropy of particle production is commonly used in high-energy nuclear collisions to study the early evolution of the expanding system. The prolate shape of uranium nuclei makes it possible to study how the geometry of the colliding nuclei affects #12;final state anisotropies. It also provides a unique opportunity to understand how entropy is produced in heavy ion collisions. In this paper, the two- and four- particle cumulant v2 (v2{2} and v2{4}) from U+U collisions at ?sNN = 193 GeV and Au+Au collisions at ?sNN = 200 GeV for inclusive charged hadrons will be presented. The STAR Zero Degree Calorimeters are used to select very central collisions. Differences were observed between the multiplicity dependence of v2{2} for most central Au+Au and U+U collisions. The multiplicity dependence of v2{2} in central collisions were compared to Monte Carlo Glauber model predictions and it was seen that this model cannot explain the present results. (auth)

  5. ANALYSIS OF ANISOTROPY IN ELASTIC CONSTANTS OF SiCp/2124 Al METAL MATRIX COMPOSITES

    E-Print Network [OSTI]

    Hong, Soon Hyung

    ANALYSIS OF ANISOTROPY IN ELASTIC CONSTANTS OF SiCp/2124 Al METAL MATRIX COMPOSITES H.K. Jung* , Y; Metal matrix composite; Elastic constants; Aspect ratio; Anisotropy 1. Introduction Metal matrix composites (MMCs) are becoming attractive materials for advanced aerospace structures because

  6. Voltage control of magnetic anisotropy in Fe films with quantum well states

    E-Print Network [OSTI]

    Bauer, Uwe

    The influence of a gate voltage on magnetic anisotropy is investigated in a thin Fe film epitaxially grown on a Ag(1,1,10) substrate and covered by MgO. Oscillations in step-induced magnetic anisotropy due to quantum well ...

  7. Optical anisotropy and liquid-crystal alignment properties of rubbed polyimide layers

    E-Print Network [OSTI]

    Exeter, University of

    Optical anisotropy and liquid-crystal alignment properties of rubbed polyimide layers FUZI YANG polyimide layers and the rubbing process is investigated using the recently developed polarization-conversion guided mode technique. Results indicate that the effective optical anisotropy of the polyimide layers may

  8. Azimuthal anisotropy in high-energy heavy-ion collisions at RHIC energies

    E-Print Network [OSTI]

    ShinIchi Esumi

    2004-05-19T23:59:59.000Z

    Directed and elliptic event anisotropy parameters measured in the experiments at relativistic heavy-ion collider are presented. The possible origin of the measured elliptic anisotropy parameter $v_2$ and its sensitivity to the early phase of the high-energy heavy-ion collisions are discussed.

  9. Plasticity-induced structural anisotropy of silica glass C. L. Rountree1

    E-Print Network [OSTI]

    Boyer, Edmond

    Plasticity-induced structural anisotropy of silica glass C. L. Rountree1 , D. Vandembroucq2 , M anisotropic structure after extended shear plastic flow. This anisotropy which survives for an un- stressed tetrahedra microstructure remains mostly unaltered. PACS numbers: 62.20.F, 81.05.Kf Plasticity of amorphous

  10. Imprints of expansion onto the local anisotropy of solar wind turbulence

    E-Print Network [OSTI]

    Verdini, Andrea

    2015-01-01T23:59:59.000Z

    We study the anisotropy of II-order structure functions defined in a frame attached to the local mean field in three-dimensional (3D) direct numerical simulations of magnetohydrodynamic turbulence, including or not the solar wind expansion. We simulate spacecraft flybys through the numerical domain by taking increments along the radial (wind) direction that forms an angle of $45^o$ with the ambient magnetic field. We find that only when expansion is taken into account, do the synthetic observations match the 3D anisotropy observed in the solar wind, including the change of anisotropy with scales. Our simulations also show that the anisotropy changes dramatically when considering increments oblique to the radial directions. Both results can be understood by noting that expansion reduces the radial component of the magnetic field at all scales, thus confining fluctuations in the plane perpendicular to the radial. Expansion is thus shown to affect not only the (global) spectral anisotropy, but also the local ani...

  11. Is inner core seismic anisotropy a marker of plastic flow of cubic iron?

    E-Print Network [OSTI]

    Lincot, A; Cardin, Philippe

    2015-01-01T23:59:59.000Z

    This paper investigates whether observations of seismic anisotropy are compatible with a cubic structure of the inner core Fe alloy. We assume that anisotropy is the result of plastic deformation within a large scale flow induced by preferred growth at the inner core equator. Based on elastic moduli from the literature, bcc- or fcc-Fe produce seismic anisotropy well below seismic observations ($\\textless{}0.4\\%$). A Monte-Carlo approach allows us to generalize this result to any form of elastic anisotropy in a cubic system. Within our model, inner core global anisotropy is not compatible with a cubic structure of Fe alloy. Hence, if the inner core material is indeed cubic, large scale coherent anisotropic structures, incompatible with plastic deformation induced by large scale flow, must be present.

  12. Geometrical vs wave optics under gravitational waves

    E-Print Network [OSTI]

    Raymond Angélil; Prasenjit Saha

    2015-05-20T23:59:59.000Z

    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. Full-Wave Algorithm to Model Effects of Bedding Slopes on the Response of Subsurface Electromagnetic Geophysical Sensors near Unconformities

    E-Print Network [OSTI]

    Sainath, Kamalesh

    2015-01-01T23:59:59.000Z

    We propose a full-wave pseudo-analytical numerical electromagnetic (EM) algorithm to model subsurface induction sensors, traversing planar-layered geological formations of arbitrary EM material anisotropy and loss, which are used, for example, in the exploration of hydrocarbon reserves. Unlike past pseudo-analytical planar-layered modeling algorithms that impose parallelism between the formation's bed junctions however, our method involves judicious employment of Transformation Optics techniques to address challenges related to modeling arbitrarily-oriented, relative slope (i.e., tilting) between said junctions. The algorithm exhibits this flexibility, both with respect to anisotropy in the formation layers as well as junction tilting, via employing special planar slabs that coat each "flattened" (i.e., originally tilted) planar interface, locally redirecting the incident wave within the coating slabs to cause wave fronts to interact with the flattened interfaces as if they were still tilted with a specific, ...

  14. Electric-field-induced spin wave generation using multiferroic magnetoelectric cells

    SciTech Connect (OSTI)

    Cherepov, Sergiy; Khalili Amiri, Pedram; Alzate, Juan G.; Wong, Kin; Lewis, Mark; Upadhyaya, Pramey; Nath, Jayshankar; Bao, Mingqiang; Wang, Kang L. [Department of Electrical Engineering, University of California, Los Angeles, California 90095 (United States); Bur, Alexandre; Wu, Tao; Carman, Gregory P. [Department of Mechanical and Aerospace Engineering, University of California, Los Angeles, California 90095 (United States); Khitun, Alexander [Department of Electrical Engineering, University of California, Riverside, California 92521 (United States)

    2014-02-24T23:59:59.000Z

    In this work, we report on the demonstration of voltage-driven spin wave excitation, where spin waves are generated by multiferroic magnetoelectric (ME) cell transducers driven by an alternating voltage, rather than an electric current. A multiferroic element consisting of a magnetostrictive Ni film and a piezoelectric [Pb(Mg{sub 1/3}Nb{sub 2/3})O{sub 3}]{sub (1?x)}–[PbTiO{sub 3}]{sub x} substrate was used for this purpose. By applying an AC voltage to the piezoelectric, an oscillating electric field is created within the piezoelectric material, which results in an alternating strain-induced magnetic anisotropy in the magnetostrictive Ni layer. The resulting anisotropy-driven magnetization oscillations propagate in the form of spin waves along a 5??m wide Ni/NiFe waveguide. Control experiments confirm the strain-mediated origin of the spin wave excitation. The voltage-driven spin wave excitation, demonstrated in this work, can potentially be used for low-dissipation spin wave-based logic and memory elements.

  15. First Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Foreground Emission

    E-Print Network [OSTI]

    C. Bennett; R. S. Hill; G. Hinshaw; M. R. Nolta; N. Odegard; L. Page; D. N. Spergel; J. L. Weiland; E. L. Wright; M. Halpern; N. Jarosik; A. Kogut; M. Limon; S. S. Meyer; G. S. Tucker; E. Wollack

    2003-06-05T23:59:59.000Z

    Full sky maps are made in five microwave frequency bands to separate the temperature anisotropy of the CMB from foreground emission. We define masks that excise regions of high foreground emission. The effectiveness of template fits to remove foreground emission from the WMAP data is examined. These efforts result in a CMB map with minimal contamination and a demonstration that the WMAP CMB power spectrum is insensitive to residual foreground emission. We construct a model of the Galactic emission components. We find that the Milky Way resembles other normal spiral galaxies between 408 MHz and 23 GHz, with a synchrotron spectral index that is flattest (beta ~ -2.5) near star-forming regions, especially in the plane, and steepest (beta ~ -3) in the halo. The significant synchrotron index steepening out of the plane suggests a diffusion process in which the halo electrons are trapped in the Galactic potential long enough to suffer synchrotron and inverse Compton energy losses and hence a spectral steepening. The synchrotron index is steeper in the WMAP bands than in lower frequency radio surveys, with a spectral break near 20 GHz to beta < -3. The modeled thermal dust spectral index is also steep in the WMAP bands, with beta ~ 2.2. Microwave and H alpha measurements of the ionized gas agree. Spinning dust emission is limited to < ~5% of the Ka-band foreground emission. A catalog of 208 point sources is presented. Derived source counts suggest a contribution to the anisotropy power from unresolved sources of (15.0 +- 1.4) 10^{-3} microK^2 sr at Q-band and negligible levels at V-band and W-band.

  16. CONSTRAINTS ON THE SOURCE OF ULTRA-HIGH-ENERGY COSMIC RAYS USING ANISOTROPY VERSUS CHEMICAL COMPOSITION

    SciTech Connect (OSTI)

    Liu, Ruo-Yu; Wang, Xiang-Yu [School of Astronomy and Space Science, Nanjing University, Nanjing 210093 (China); Taylor, Andrew M. [Dublin Institute for Advanced Studies, 31 Fitzwilliam Place, Dublin 2 (Ireland); Lemoine, Martin [Institut d'Astrophysique de Paris, CNRS, UPMC, 98 bis Boulevard Arago, F-75014 Paris (France); Waxman, Eli, E-mail: lemoine@iap.fr [Physics Faculty, Weizmann Institute, P.O. Box 26, Rehovot 7600 (Israel)

    2013-10-20T23:59:59.000Z

    The joint analysis of anisotropy signals and chemical composition of ultra-high-energy cosmic rays offers strong potential for shedding light on the sources of these particles. Following up on an earlier idea, this paper studies the anisotropies produced by protons of energy >E/Z, assuming that anisotropies at energy >E have been produced by nuclei of charge Z, which share the same magnetic rigidity. We calculate the number of secondary protons produced through photodisintegration of the primary heavy nuclei. Making the extreme assumption that the source does not inject any proton, we find that the source(s) responsible for anisotropies such as reported by the Pierre Auger Observatory should lie closer than ?20-30, 80-100, and 180-200 Mpc if the anisotropy signal is mainly composed of oxygen, silicon, and iron nuclei, respectively. A violation of this constraint would otherwise result in the secondary protons forming a more significant anisotropy signal at lower energies. Even if the source were located closer than this distance, it would require an extraordinary metallicity ?> 120, 1600, and 1100 times solar metallicity in the acceleration zone of the source, for oxygen, silicon, and iron, respectively, to ensure that the concomitantly injected protons do not produce a more significant low-energy anisotropy. This offers interesting prospects for constraining the nature and the source of ultra-high-energy cosmic rays with the increase in statistics expected from next-generation detectors.

  17. Water Waves Roger Grimshaw

    E-Print Network [OSTI]

    ,2) provide a kinematic description of water waves, which to this point means that the conditionsWater 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

  18. 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

  19. Environment-induced anisotropy and the sensitivity of the radical pair mechanism in the avian compass

    E-Print Network [OSTI]

    Alejandro Carrillo; Marcio F. Cornelio; Marcos C. de Oliveira

    2013-04-10T23:59:59.000Z

    Earth's magnetic field is essential for orientation in birds migration. The most promising explanation for this orientation is the photo-stimulated radical pair (RP) mechanism, conjectured to occur in cryptochrome photoreceptors. The radicals must have an intrinsic anisotropy in order to define a reference frame for the compass. This anisotropy, when introduced through hyperfine interactions, imposes immobility of the RP, and implies that entanglement between the unpaired electrons of the RP is preserved over long coherence times. We show that this kind of anisotropy, and consequently the entanglement in the model, are not necessary for the proper functioning of the compass. Classically correlated initial conditions for the RP, subjected to a fast decoherence process, are able to provide the anisotropy required. The environment in which the RP is immersed is then responsible for the reference frame of the compass, relaxing the immobility assumption. This fact significantly expands the range of applicability of the RP mechanism providing more elements for experimental search.

  20. CALCUL QUANTIQUE DE L'ANISOTROPIE DIAMAGNTIQUE DES MOLCULES ORGANIQUES PRINCIPAUX GROUPES D'HYDROCARBURES AROMATIQUES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    GROUPES D'HYDROCARBURES AROMATIQUES Par MM. GASTON BERTHIER, MARGEL MAYOT et BERNARD PULLMAN. Sommaire'anisotropie diamagnétique des principaux groupes d'hydrocarbures conjugués : molécules polybenzé- niques condensées, phényléthylènes, polyphényles, dérivés quinodiméthaniques des hydrocarbures aroma- tiques, hydrocarbures

  1. Evaluating permeability anisotropy in the early Jurassic Tilje formation, offshore mid-Norway

    E-Print Network [OSTI]

    Aliyev, Kanan

    2005-11-01T23:59:59.000Z

    The problem of evaluating permeability anisotropy in the Tilje Formation, Heidrum field, offshore mid-Norway, has been investigated by the Statoil Research Centre by a detailed combination of the geological and petrophysical data. The large...

  2. Structure, magnetic properties and magnetoelastic anisotropy in epitaxial Sr(Ti???Co?)O? films

    E-Print Network [OSTI]

    Bi, Lei

    We report the structure, magnetic properties and magnetoelastic anisotropy of epitaxial Sr(Ti???Co?)O? films grown on LaAlO? (001) and SrTiO? (001) substrates by pulsed laser deposition. Room temperature ferromagnetism was ...

  3. CMB anisotropy power spectrum using linear combinations of WMAP maps Rajib Saha,1,2,3

    E-Print Network [OSTI]

    Souradeep, Tarun

    CMB anisotropy power spectrum using linear combinations of WMAP maps Rajib Saha,1,2,3 Simon Prunet year WMAP data by Saha et al. 2006. All previous estimates of the power spectrum of the CMB are based

  4. Azimuthal Anisotropy in Heavy Ion Collisions from the Maximum Entropy Method

    E-Print Network [OSTI]

    Pirner, Hans J

    2014-01-01T23:59:59.000Z

    We investigate the azimuthal anisotropy v2 of particle production in nucleus-nucleus collisions in the maximum entropy approach. This necessitates two new parameters delta and lambda2. The parameter delta describes the deformation of transverse configuration space and is related to the anisotropy of the overlap zone of the two nuclei. The parameter lambda2 defines the anisotropy of the particle distribution in momentum space. Assuming deformed flux tubes at the early stage of the collision we relate the momentum to the space asymmetry i.e. lambda2 to delta with the uncertainty relation. We compute the anisotropy v2 as a function of centrality, transverse momentum and rapidity using gluon-hadron duality. The general features of LHC data are reproduced.

  5. Azimuthal Anisotropy in Heavy Ion Collisions from the Maximum Entropy Method

    E-Print Network [OSTI]

    Hans J. Pirner

    2014-05-09T23:59:59.000Z

    We investigate the azimuthal anisotropy v2 of particle production in nucleus-nucleus collisions in the maximum entropy approach. This necessitates two new parameters delta and lambda2. The parameter delta describes the deformation of transverse configuration space and is related to the anisotropy of the overlap zone of the two nuclei. The parameter lambda2 defines the anisotropy of the particle distribution in momentum space. Assuming deformed flux tubes at the early stage of the collision we relate the momentum to the space asymmetry i.e. lambda2 to delta with the uncertainty relation. We compute the anisotropy v2 as a function of centrality, transverse momentum and rapidity using gluon-hadron duality. The general features of LHC data are reproduced.

  6. Mechanical Flow Response and Anisotropy of Ultra-Fine Grained Magnesium and Zinc Alloys 

    E-Print Network [OSTI]

    Al Maharbi, Majid H.

    2011-02-22T23:59:59.000Z

    MECHANICAL FLOW RESPONSE AND ANISOTROPY IN ULTRA-FINE GRAINED MAGNESIUM AND ZINC ALLOYS A Dissertation by MAJID AL MAHARBI Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... of the requirements for the degree of DOCTOR OF PHILOSOPHY December 2009 Major Subject: Materials Science and Engineering MECHANICAL FLOW RESPONSE AND ANISOTROPY IN ULTRA-FINE GRAINED MAGNESIUM AND ZINC ALLOYS A Dissertation by MAJID AL...

  7. Structure formation and CMBR anisotropy spectrum in the inflessence model

    E-Print Network [OSTI]

    A. A. Sen; V. F. Cardone; S. Capozziello; A. Troisi

    2006-07-25T23:59:59.000Z

    The inflessence model has recently been proposed in an attempt to explain both early inflation and present day accelerated expansion within a single mechanism. The model has been successfully tested against the Hubble diagram of Type Ia Supernovae, the shift parameter, and the acoustic peak parameter. As a further mandatory test, we investigate here structure formation in the inflessence model determining the evolution of matter density contrast $\\delta \\equiv \\delta \\rho_M/\\rho_M$ in the linear regime. We compare the growth factor $D(a) \\equiv \\delta/a$ and the growth index $f(z) \\equiv d\\ln{\\delta}/d\\ln{a}$ to these same quantities for the successful concordance $\\Lambda$CDM model with a particular emphasis on the role of the inflessence parameters $(\\gamma, z_Q)$. We also evaluate the anisotropy spectrum of the cosmic microwave background radiation (CMBR) to check whether the inflessence model may be in agreement with the observations. We find that, for large values of $(\\gamma, z_Q)$, structure formation proceeds in a similar way to that in the $\\Lambda$CDM scenario, and it is also possible to nicely fit the CMBR spectrum.

  8. Dielectric anisotropy in polar solvents under external fields

    E-Print Network [OSTI]

    Sahin Buyukdagli

    2014-12-14T23:59:59.000Z

    We investigate dielectric saturation and increment in polar liquids under external fields. We couple a previously introduced dipolar solvent model to a uniform electric field and derive the electrostatic kernel of interacting dipoles. This procedure allows an unambiguous definition of the liquid dielectric permittivity embodying non-linear dielectric response and correlation effects.We find that the presence of the external field results in a dielectric anisotropy characterized by a two-component dielectric permittivity tensor. The increase of the electric field amplifies the permittivity component parallel to the field direction, i.e. dielectric increment is observed along the field. However, the perpendicular component is lowered below the physiological permittivity, indicating dielectric saturation perpendicular to the field. By comparison with Molecular Dynamics simulations from the literature, we show that the mean-field level dielectric response theory underestimates dielectric saturation. The inclusion of dipolar correlations at the weak-coupling level intensify the mean-field level dielectric saturation and improves the agreement with simulation data at weak electric fields. The correlation-corrected theory predicts as well the presence of a metastable configuration corresponding to the antiparallel alignment of dipoles with the field. This prediction can be verified by solvent-explicit simulations where solvent molecules are expected to be trapped transiently in this metastable state.

  9. Large-scale anisotropy of TeV-band cosmic rays

    SciTech Connect (OSTI)

    Kumar, Rahul; Eichler, David [Phyiscs Department, Ben-Gurion University, Be'er-Sheba 84105 (Israel)

    2014-04-20T23:59:59.000Z

    The expected anisotropy in the 1 to 10{sup 4} TeV energy range is calculated for Galactic cosmic rays with both anisotropy in the diffusion tensor and source discreteness taken into account. We find that if the sources are distributed radially (but with azimuthal symmetry) in proportion to Galactic pulsars, the expected anisotropy almost always exceeds the observational limits by one order of magnitude in the case of isotropic diffusion. If the radial diffusion is more than an order of magnitude smaller than the azimuthal diffusion rate, the radial gradient of the sources can be accommodated about 5% of the time. If the sources are concentrated in the spiral arms, then the anisotropy depends on our location between them, but in some spatial window, roughly equidistant from adjacent spiral arms, the observational constraints on anisotropy are obeyed roughly 20%-30% of the time for extremely anisotropic diffusion. The solar system is in that window less than 10% of the time, but it may be there now. Under the assumption of isotropic diffusion, nearby supernovae are found to produce a discreteness anisotropy that is nearly two orders of magnitude in excess of the observational limit if all supernovae are assumed to contribute equally with a source rate 1 in every 100 years.

  10. Photon wave function

    E-Print Network [OSTI]

    Iwo Bialynicki-Birula

    2005-08-26T23:59:59.000Z

    Photon wave function is a controversial concept. Controversies stem from the fact that photon wave functions can not have all the properties of the Schroedinger wave functions of nonrelativistic wave mechanics. Insistence on those properties that, owing to peculiarities of photon dynamics, cannot be rendered, led some physicists to the extreme opinion that the photon wave function does not exist. I reject such a fundamentalist point of view in favor of a more pragmatic approach. In my view, the photon wave function exists as long as it can be precisely defined and made useful.

  11. Phase-controllable spin wave generation in iron garnet by linearly polarized light pulses

    SciTech Connect (OSTI)

    Yoshimine, Isao; Iida, Ryugo; Shimura, Tsutomu [Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505 (Japan); Satoh, Takuya, E-mail: satoh@phys.kyushu-u.ac.jp [Institute of Industrial Science, The University of Tokyo, Tokyo 153-8505 (Japan); PRESTO, Japan Science and Technology Agency, Tokyo 102-0076 (Japan); Department of Physics, Kyushu University, Fukuoka 812-8581 (Japan); Stupakiewicz, Andrzej; Maziewski, Andrzej [Laboratory of Magnetism, Faculty of Physics, University of Bialystok, Bialystok 15-424 (Poland)

    2014-07-28T23:59:59.000Z

    A phase-controlled spin wave was non-thermally generated in bismuth-doped rare-earth iron garnet by linearly polarized light pulses. We controlled the initial phase of the spin wave continuously within a range of 180° by changing the polarization azimuth of the excitation light. The azimuth dependences of the initial phase and amplitude of the spin wave were attributed to a combination of the inverse Cotton-Mouton effect and photoinduced magnetic anisotropy. Temporally and spatially resolved spin wave propagation was observed with a CCD camera, and the waveform was in good agreement with calculations. A nonlinear effect of the spin excitation was observed for excitation fluences higher than 100 mJ/cm{sup 2}.

  12. Rogue Wave Modes for the Long Wave-Short Wave Resonance Kwok Wing CHOW*(1)

    E-Print Network [OSTI]

    1 Rogue Wave Modes for the Long Wave-Short Wave Resonance Model Kwok Wing CHOW*(1) , Hiu Ning CHAN.45.Yv; 47.35.Fg ABSTRACT The long wave-short wave resonance model arises physically when the phase velocity of a long wave matches the group velocity of a short wave. It is a system of nonlinear evolution

  13. 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, ...

  14. New wave generation

    E-Print Network [OSTI]

    Mercier, Matthieu J.

    We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (Exp. Fluids, vol. 42, 2007, pp. 123–130). This ...

  15. Bragg grating rogue wave

    E-Print Network [OSTI]

    Degasperis, Antonio; Aceves, Alejandro B

    2015-01-01T23:59:59.000Z

    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.

  16. Internal wave instability: Wave-wave versus wave-induced mean flow interactions

    E-Print Network [OSTI]

    Sutherland, Bruce

    , known as parametric sub- harmonic instability, results generally when a disturbance of one frequency imparts energy to disturbances of half that frequency.13,14 Generally, a plane periodic internal wave, energy from primary waves is transferred, for example, to waves with half frequency. Self

  17. Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino

    E-Print Network [OSTI]

    Merlino, Robert L.

    Dust-Acoustic Waves: Visible Sound Waves Robert L. Merlino Department of Physics and Astronomy with their announcement that: "We find that a new type of sound wave, namely, the dust-acoustic waves, can appear" [1 and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some

  18. 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

  19. Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics 

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14T23:59:59.000Z

    Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...

  20. Coastal Wave Generation and Wave Breaking over Terrain: Two Problems in Mesoscale Wave Dynamics

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14T23:59:59.000Z

    Two problems in mesoscale wave dynamics are addressed: (i) wave-turbulence interaction in a breaking mountain wave and (ii) gravity wave generation associated with coastal heating gradients. The mean and turbulent structures in a breaking mountain...

  1. A comparison between matter wave and light wave interferometers for the detection of gravitational waves

    E-Print Network [OSTI]

    Pacôme Delva; Marie-Christine Angonin; Philippe Tourrenc

    2006-09-20T23:59:59.000Z

    We calculate and compare the response of light wave interferometers and matter wave interferometers to gravitational waves. We find that metric matter wave interferometers will not challenge kilometric light wave interferometers such as Virgo or LIGO, but could be a good candidate for the detection of very low frequency gravitational waves.

  2. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30T23:59:59.000Z

    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.

  3. Beta-dependent upper bound on ion temperature anisotropy in a laboratory plasma

    SciTech Connect (OSTI)

    Keiter, Paul A. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Scime, Earl E. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Balkey, Matthew M. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Boivin, Robert [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Kline, John L. [West Virginia University, Morgantown, West Virginia 26506 (United States)] [West Virginia University, Morgantown, West Virginia 26506 (United States); Gary, S. Peter [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)

    2000-03-01T23:59:59.000Z

    Laser induced fluorescence measurements of ion temperatures, parallel and perpendicular to the local magnetic field, in the Large Experiment on Instabilities and Anisotropies space simulation chamber (a steady-state, high beta, argon plasma) display an inverse correlation between the upper bound on the ion temperature anisotropy and the parallel ion beta ({beta}=8{pi}nkT/B{sup 2}). These observations are consistent with in situ spacecraft measurements in the Earth's magnetosheath and with a theoretical/computational model that predicts that such an upper bound is imposed by scattering from enhanced fluctuations due to growth of the ion cyclotron anisotropy instability (the Alfven ion cyclotron instability). (c) 2000 American Institute of Physics.

  4. Anisotropy enhancement of the Casimir-Polder force between a nanoparticle and graphene

    E-Print Network [OSTI]

    Svend-Age Biehs; Girish S. Agarwal

    2014-03-21T23:59:59.000Z

    We derive the analytical expressions for the thermal Casimir-Polder energy and force between a spheroidal nanoparticle above a semi-infinite material and a graphene covered interface. We analyze in detail the Casimir-Polder force between a gold nanoparticle and a single sheet of pristine graphene focusing on the impact of anisotropy. We show that the effect of anisotropy, i.e. the shape and orientation of the spheroidal nanoparticle, has a much larger influence on the force than the tunability of graphene. The effect of tuning and anisotropy both add up such that we observe a force which is between 20-50% of that in the ideal metal case which is much larger than the results found for the Casimir force between a metal halfspace and a layer of graphene.

  5. Electric field controlled reversible magnetic anisotropy switching studied by spin rectification

    SciTech Connect (OSTI)

    Zhou, Hengan; Fan, Xiaolong, E-mail: fanxiaolong@lzu.edu.cn; Wang, Fenglong; Jiang, Changjun; Rao, Jinwei; Zhao, Xiaobing; Xue, Desheng [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China)] [Key Laboratory for Magnetism and Magnetic Materials of Ministry of Education, Lanzhou University, Lanzhou 730000 (China); Gui, Y. S.; Hu, C.-M. [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)] [Department of Physics and Astronomy, University of Manitoba, Winnipeg, Manitoba R3T 2N2 (Canada)

    2014-03-10T23:59:59.000Z

    In this letter, spin rectification was used to study the electric field controlled dynamic magnetic properties of the multiferroic composite which is a Co stripe with induced in-plane anisotropy deposited onto a Pb(Mg{sub 1?3}Nb{sub 2?3})O{sub 3}-PbTiO{sub 3} substrate. Due to the coupling between piezoelectric and magnetoelastic effects, a reversible in-plane anisotropy switching has been realized by varying the history of the applied electric field. This merit results from the electric hysteresis of the polarization in the nonlinear piezoelectric regime, which has been proved by a butterfly type electric field dependence of the in-plane anisotropy field. Moreover, the electric field dependent effective demagnetization field and linewidth have been observed at the same time.

  6. Anisotropy enhancement of the Casimir-Polder force between a nanoparticle and graphene

    E-Print Network [OSTI]

    Svend-Age Biehs; Girish S. Agarwal

    2015-03-27T23:59:59.000Z

    We derive the analytical expressions for the thermal Casimir-Polder energy and force between a spheroidal nanoparticle above a semi-infinite material and a graphene covered interface. We analyze in detail the Casimir-Polder force between a gold nanoparticle and a single sheet of pristine graphene focusing on the impact of anisotropy. We show that the effect of anisotropy, i.e. the shape and orientation of the spheroidal nanoparticle, has a much larger influence on the force than the tunability of graphene. The effect of tuning and anisotropy both add up such that we observe a force which is between 20-50% of that in the ideal metal case which is much larger than the results found for the Casimir force between a metal halfspace and a layer of graphene.

  7. Development and anisotropy of three-dimensional turbulence in a current sheet

    SciTech Connect (OSTI)

    Onofri, M.; Veltri, P.; Malara, F. [Dipartimento di Fisica, Universita della Calabria, via P. Bucci, 87036 Rende (Serbia and Montenegro) (Italy)

    2007-06-15T23:59:59.000Z

    The nonlinear evolution of three-dimensional reconnection instabilities are studied in a current sheet where many resonant surfaces are simultaneously present at different locations of the simulation domain. The nonlinear evolution produces the development of anisotropic magnetohydrodynamic turbulence. The development of the energy spectrum is followed until the energy is transported to the dissipative length scale and the anisotropy of the spectrum is analyzed. The energy cascade is affected by the Alfven effect and it takes place mainly in the direction perpendicular to the local average magnetic field. Anisotropy is also affected by propagation of perturbations across the main magnetic field, due to the growth of a transverse component related to reconnection. The direction of anisotropy varies with the position in space. The spectral index is different both from what is found in homogeneous isotropic turbulence and from the values predicted for magnetohydrodynamic turbulence with a uniform large-scale magnetic field.

  8. Re-Analysis of the Marinov Light-Speed Anisotropy Experiment

    E-Print Network [OSTI]

    Cahill, R T

    2006-01-01T23:59:59.000Z

    The anisotropy of the speed of light at 1 part in 10^3 has been detected by Michelson and Morley (1887), Miller (1925/26), Illingworth (1927), Joos (1930), Jaseja et al. (1964), Torr and Kolen (1984), De Witte (1991) and Cahill (2006) using a variety of experimental techniques, from gas-mode Michelson interferometers to one-way RF coaxial cable propagation timing. All agree on the speed, right ascension and declination of the anisotropy velocity. The Stephan Marinov experiment (1984) detected a light speed anisotropy using a mechanical coupled shutters technique which has holes in co-rotating disks, essentially a one-way version of the Fizeau mechanical round-trip speed-of-light experiment. The Marinov data is re-analysed after correcting for a number of errors, and the results of his experiment now agree with the above experiments.

  9. Structural controlled magnetic anisotropy in Heusler L1{sub 0}-MnGa epitaxial thin films

    SciTech Connect (OSTI)

    Wang Kangkang; Lu Erdong; Smith, Arthur R. [Department of Physics and Astronomy, Nanoscale and Quantum Phenomena Institute, Ohio University, Athens, Ohio 45701 (United States); Knepper, Jacob W.; Yang Fengyuan [Department of Physics, Ohio State University, 191 Woodruff Ave., Columbus, Ohio 43210 (United States)

    2011-04-18T23:59:59.000Z

    Ferromagnetic L1{sub 0}-MnGa thin films have been epitaxially grown on GaN, sapphire, and MgO substrates using molecular beam epitaxy. Using diffraction techniques, the epitaxial relationships are determined. It is found that the crystalline orientation of the films differ due to the influence of the substrate. By comparing the magnetic anisotropy to the structural properties, a clear correlation could be established indicating that the in-plane and out-of-plane anisotropy is directly determined by the crystal orientation of the film and could be controlled via selection of the substrates. This result could be helpful in tailoring magnetic anisotropy in thin films for spintronic applications.

  10. Nonlinear spherical Alfven waves

    E-Print Network [OSTI]

    Ulf Torkelsson; G. Christopher Boynton

    1997-09-23T23:59:59.000Z

    We present an one-dimensional numerical study of Alfven waves propagating along a radial magnetic field. Neglecting losses, any spherical Alfven wave, no matter how small its initial amplitude is, becomes nonlinear at sufficiently large radii. From previous simulations of Alfven waves in plane parallel atmospheres we did expect the waves to steepen and produce current sheets in the nonlinear regime, which was confirmed by our new calculations. On the other hand we did find that even the least nonlinear waves were damped out almost completely before 10 solar radii. A damping of that kind is required by models of Alfven wave-driven winds from old low-mass stars as these winds are mainly accelerated within a few stellar radii.

  11. OBSERVATION OF COSMIC-RAY ANISOTROPY WITH THE ICETOP AIR SHOWER ARRAY

    E-Print Network [OSTI]

    Aartsen, M. G.; Besson, David Zeke

    2013-02-15T23:59:59.000Z

    for any particular model, they lend support to scenarios where the large-scale anisotropy is a superposition of the flux from a few nearby sources. The sparse spatial distribution and the different ages of nearby supernova remnants are expected to lead... shower array at the south pole. IceTop, an integral part of the IceCube detector, is sensitive to cosmic rays between 100 TeV and 1 EeV. With the current size of the IceTop data set, searches for anisotropy at the 10?3 level can, for the first time...

  12. A study of magnetic anisotropy energy in CuMn spin glass

    E-Print Network [OSTI]

    Allen, Christine Adele

    1986-01-01T23:59:59.000Z

    A STUDY OF MAGNETIC ANISOTROPY ENERGY IN CuMn SPIN GLASS A Thesis by CHRISTINE ADELE ALLEN Submitted to the Graduate College of Texas ARM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE August 1986... Major Subject: Physics A STUDY OF MAGNETIC ANISOTROPY ENERGY IN CuMn SPIN GLASS A Thesis by CHRISTINE ADELE ALLEN Approved as to style and content by: Thomas W. Adair, III (Chai man of Committee) Robert A. enefick (Member) Donald L. Parker...

  13. Maskelynite formation via solid-state transformation: Evidence of infrared and x-ray anisotropy

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

    Jaret, Steven J.; Ehm, Lars; Woerner, William R.; Phillips, Brian L.; Nekvasil, Hanna; Wright, Shawn P.; Glotch, Timothy D.

    2015-03-01T23:59:59.000Z

    We present optical microscopy, micro-Raman spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, high-energy X-ray total scattering experiments, and micro-Fourier transform infrared (micro-FTIR) spectroscopy on shocked labradorite from the Lonar Crater, India. We show that maskelynite of shock class 2 is structurally more similar to fused glass than to crystalline plagioclase. However, there are slight but significant differences – preservation of original pre-impact igneous zoning, anisotropy at Infrared wavelengths, X-ray anisotropy, and preservation of some intermediate range order – which are all consistent with a solid-state transformation formation of maskelynite.

  14. Structure-borne sound Flexural wave (bending wave)

    E-Print Network [OSTI]

    Berlin,Technische Universität

    1 Structure-borne sound · Flexural wave (bending wave) »One dimensional (beam) +(/x)dx +(/x)dx = (/x) (/x)dx=(2/x2)dx Mz +(Mz/x)dx Mz vy Fy Fy +(Fy/x)dx Structure-borne sound · Bending wave ­ flexural wave #12;2 Structure-borne sound · Two obliquely propagating waves + - + + - + - Structure

  15. 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 #12;66 2. Wave Propagation Theory quantities of the quiescent (time independent) medium are identified perturbations is much smaller than the speed of sound. 2.1.1 The Nonlinear Wave Equation Retaining higher

  16. Wave momentum flux parameter: a descriptor for nearshore waves

    E-Print Network [OSTI]

    US Army Corps of Engineers

    Wave momentum flux parameter: a descriptor for nearshore waves Steven A. Hughes* US Army Engineer Available online 7 October 2004 Abstract A new parameter representing the maximum depth-integrated wave momentum flux occurring over a wave length is proposed for characterizing the wave contribution

  17. Pump-Probe Polarization Anisotropy Study of Femtosecond Energy Transfer within the Photosynthetic Reaction Center of Rhodobacter sphaeroides R26

    E-Print Network [OSTI]

    Lang, Matthew

    Pump-Probe Polarization Anisotropy Study of Femtosecond Energy Transfer within the Photosynthetic) in the photosynthetic reaction center has been time resolved with pump-probe polarization anisotropy measurements using artifacts from saturation and photoexcitation of incompletely relaxed reaction centers. The pump excitation

  18. -Wavelet analysis for detecting anisotropy in point patterns -277 Journal of Vegetation Science 15: 277-284, 2004

    E-Print Network [OSTI]

    Rosenberg, Michael S.

    - Wavelet analysis for detecting anisotropy in point patterns - 277 Journal of Vegetation Science methods designed for continuously distributed data. Wavelet analysis, a booming approach to studying into the ecological literature. A simple adaptation of wavelet analysis is proposed for the detection of anisotropy

  19. Seismic Anisotropy and Mantle flow beneath Western Venezuela Jeniffer Masy,1 Fenglin Niu1 and Alan Levander1

    E-Print Network [OSTI]

    Alvarez, Pedro J.

    . Seismic anisotropy has been widely used to measure upper mantle deformation from past and present orogenic. Here we present measure- ments of seismic anisotropy from the BOLIVAR broadband seismic deployment an ellipsoid path. Note the signifcant amount SKS energy on the transverse component, an indication

  20. hal-00196134,version1-12Dec2007 Analysis of anisotropy crossover due to oxygen in Pt/Co/MOx

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    hal-00196134,version1-12Dec2007 Analysis of anisotropy crossover due to oxygen in Pt/Co/MOx-ray spectroscopy measurements have been performed on a se- ries of Pt/Co/MOx trilayers (M=Al, Mg, Ta...) in order to investigate the role of oxidation in the onset of perpendicular magnetic anisotropy at the Co/MOx interface

  1. Project EARTH-13-SHELL4: The geological significance of seismic anisotropy of fine-grained sedimentary sequences

    E-Print Network [OSTI]

    Henderson, Gideon

    hydrocarbon accumulations or for CO2 storage sites, and increasingly as reservoirs for shale gas plays. Seismic data can help elucidate systematic variations in critical physical parameters governing the fluid-azimuth anisotropy data. The anisotropy is an output from the velocity analysis but there seems to be only a weak

  2. New wave generation

    E-Print Network [OSTI]

    Mercier, Matthieu J; Mathur, Manikandan; Gostiaux, Louis; Peacock, Thomas; Dauxois, Thierry

    2015-01-01T23:59:59.000Z

    We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (2007). This mechanism, which involves a tunable source comprised of oscillating plates, has so far been used for a few fundamental studies of internal waves, but its full potential has yet to be realized. Our studies reveal that this approach is capable of producing a wide variety of two-dimensional wave fields, including plane waves, wave beams and discrete vertical modes in finite-depth stratifications. The effects of discretization by a finite number of plates, forcing amplitude and angle of propagation are investigated, and it is found that the method is remarkably efficient at generating a complete wave field despite forcing only one velocity component in a controllable manner. We furthermore find that the nature of the radiated wave field is well predicted using Fourier transforms of the spatial structure of the wave generator.

  3. Directed Relativistic Blast Wave

    E-Print Network [OSTI]

    Andrei Gruzinov

    2007-04-23T23:59:59.000Z

    A spherically symmetrical ultra-relativistic blast wave is not an attractor of a generic asymmetric explosion. Spherical symmetry is reached only by the time the blast wave slows down to non-relativistic velocities, when the Sedov-Taylor-von Neumann attractor solution sets in. We show however, that a directed relativistic explosion, with the explosion momentum close to the explosion energy, produces a blast wave with a universal intermediate asymptotic -- a selfsimilar directed ultra-relativistic blast wave. This universality might be of interest for the astrophysics of gamma-ray burst afterglows.

  4. Shear-wave splitting, lithospheric anisotropy, and mantle deformation beneath the ArabiaEurasia collision zone in Iran

    E-Print Network [OSTI]

    Hatzfeld, Denis

    ­Eurasia collision zone in Iran Ayoub Kaviani a,b,c , Denis Hatzfeld c, , Anne Paul c , Mohammad Tatar b , Keith Priestley d a Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Zanjan, Iran b International Institute of Earthquake Engineering and Seismology, P.O. Box 19395-3913, Tehran, Iran c

  5. Characterizing Fractures in the Geysers Geothermal Field by Micro-seismic Data, Using Soft Computing, Fractals, and Shear Wave Anisotropy

    Broader source: Energy.gov [DOE]

    Determine if fracturing could be used to enhance permeability; and whether dilution of existing fluids with injected water would lower corrosivity enough to allow economic production of power.

  6. Wave Energy challenges and possibilities

    E-Print Network [OSTI]

    © Wave Energy ­ challenges and possibilities By: Per Resen Steenstrup www.WaveStarEnergy.com Risø-R-1608(EN) 161 #12;© Wave energy is an old story.... The first wave energy patent is 200 years old. Over the last 100 years more than 200 new wave energy devices have been developped and more than 1.000 patents

  7. JOURNAL DE PHYSIQUE Colloque C 1, supplktnent au no 2-3, Tome 32, Fkvrier-Mars 1971, page C 1 -920 STUDIES OF MAGNETIC ANISOTROPY

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    5lEu pour etudier l'anisotropie magnetique de plusieurs grenats de terres rares deformule :RZSm~/2-x

  8. Wave-Corpuscle Mechanics for Electric Charges

    E-Print Network [OSTI]

    Babin, Anatoli; Figotin, Alexander

    2010-01-01T23:59:59.000Z

    superposition in nonlinear wave dynamics. Rev. Math. Phys.6. Babin, A. , Figotin, A. : Wave-corpuscle mechanics forV. , Fortunato, D. : Solitary waves in the nonlinear wave

  9. Wave Energy Resource Analysis for Use in Wave Energy Conversion 

    E-Print Network [OSTI]

    Pastor, J.; Liu, Y.; Dou, Y.

    2014-01-01T23:59:59.000Z

    In order to predict the response of wave energy converters an accurate representation of the wave climate resource is crucial. This paper gives an overview of wave resource modeling techniques as well as detailing a methodology for estimating...

  10. Harmonic generation of gravitational wave induced Alfven waves

    E-Print Network [OSTI]

    Mats Forsberg; Gert Brodin

    2007-11-26T23:59:59.000Z

    Here we consider the nonlinear evolution of Alfven waves that have been excited by gravitational waves from merging binary pulsars. We derive a wave equation for strongly nonlinear and dispersive Alfven waves. Due to the weak dispersion of the Alfven waves, significant wave steepening can occur, which in turn implies strong harmonic generation. We find that the harmonic generation is saturated due to dispersive effects, and use this to estimate the resulting spectrum. Finally we discuss the possibility of observing the above process.

  11. Developing de Broglie Wave

    E-Print Network [OSTI]

    J X Zheng-Johansson; P-I Johansson

    2006-08-27T23:59:59.000Z

    The electromagnetic component waves, comprising together with their generating oscillatory massless charge a material particle, will be Doppler shifted when the charge hence particle is in motion, with a velocity $v$, as a mere mechanical consequence of the source motion. We illustrate here that two such component waves generated in opposite directions and propagating at speed $c$ between walls in a one-dimensional box, superpose into a traveling beat wave of wavelength ${\\mit\\Lambda}_d$$=(\\frac{v}{c}){\\mit\\Lambda}$ and phase velocity $c^2/v+v$ which resembles directly L. de Broglie's hypothetic phase wave. This phase wave in terms of transporting the particle mass at the speed $v$ and angular frequency ${\\mit\\Omega}_d=2\\pi v /{\\mit\\Lambda}_d$, with ${\\mit\\Lambda}_d$ and ${\\mit\\Omega}_d$ obeying the de Broglie relations, represents a de Broglie wave. The standing-wave function of the de Broglie (phase) wave and its variables for particle dynamics in small geometries are equivalent to the eigen-state solutions to Schr\\"odinger equation of an identical system.

  12. JOURNAL DE PHYSIQUE Colloque C I, suppkment au no 2-3, Tome 32, Fkvrier-Mars 1971,page C 1 -186 MAGNETIC ANISOTROPY IN NICKEL AND IRON ;

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    MAGNETIC ANISOTROPY IN NICKEL AND IRON ; THE EFFECT OF PRESSURE J. J. M. FRANSE Natuurkundig Laboratorium thkoriques sur I'anisotropie magnetique et sur la magnetostric- tion du nickel et du fer, accordant beaucoup experimentaleen ce qui concerne l'anisotropie magnttiquedu nickel. Des arguments sont all& gues qui soutiennent un

  13. Mcanismes d'anisotropie dans la gravure du silicium en plasma SF6. Modle de gravure

    E-Print Network [OSTI]

    Boyer, Edmond

    377 Mécanismes d'anisotropie dans la gravure du silicium en plasma SF6. Modèle de gravure B. Petit) Résumé. - Les mécanismes de gravure du silicium en plasma de SF6 sont étudiés aux basses pressions et aux of silicon in low pressure SF6 plasma under low energy ion impact are studied using Microwave Multipolar

  14. Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field

    E-Print Network [OSTI]

    Qin, Lu-Chang

    Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field ZHEN Liang( )1 of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; 2. Department 27599-3255, USA Received 29 June 2006; accepted 15 January 2007 Abstract: Structural and magnetic

  15. Manipulation of magnetic anisotropy of Co ultrathin films by substrate engineering

    E-Print Network [OSTI]

    Hasegawa, Shuji

    Manipulation of magnetic anisotropy of Co ultrathin films by substrate engineering Yuki Saisyu September 2011) The magnetic and structural properties of Co films prepared on various substrates were-energy electron diffraction (RHEED) and scanning tunneling microscopy (STM). The magnetic signals of the Co films

  16. Nuclear modification and azimuthal anisotropy of D mesons produced in relativistic heavy ion collision

    E-Print Network [OSTI]

    Younus, Mohammed

    2015-01-01T23:59:59.000Z

    In this paper we present a phenomenological treatment of charm quark energy loss before fragmenting into D mesons and calculate nuclear modification factor, '$R_{AA}$' and azimuthal anisotropy, '$v_2$' of D mesons for lead on lead collision at LHC energy of $\\sqrt{s}$=2.76 A TeV.

  17. Effect of permeability anisotropy on buoyancy-driven flow for CO2 sequestration in saline aquifers

    E-Print Network [OSTI]

    Firoozabadi, Abbas

    ) in deep saline aquifers is considered one of the most effective methods for carbon sequestration., 48, W09539, doi:10.1029/2012WR011939.* 1. Introduction [2] Carbon sequestration in deep salineEffect of permeability anisotropy on buoyancy-driven flow for CO2 sequestration in saline aquifers

  18. Scanning Force Microscopy Studies on Molecular Packing and Friction Anisotropy in Thin Films of

    E-Print Network [OSTI]

    Kenis, Paul J. A.

    Scanning Force Microscopy Studies on Molecular Packing and Friction Anisotropy in Thin Films in bulk, was studied using differential scanning calorimetry, optical microscopy, magic angle solid were investigated at the molecular level by a combination of multimode scanning force microscopy (SFM

  19. FREE-FORM ANISOTROPY: A NEW METHOD FOR CRACK DETECTION ON PAVEMENT SURFACE IMAGES

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    FREE-FORM ANISOTROPY: A NEW METHOD FOR CRACK DETECTION ON PAVEMENT SURFACE IMAGES Tien Sy NGUYEN(1, in the segmentation step, for crack detection on road pavement images. Features which are calculated along every free on some samples of different kinds of pavements. Results of the method are also given on other kinds

  20. AUTOMATIC DETECTION AND CLASSIFICATION OF DEFECT ON ROAD PAVEMENT USING ANISOTROPY MEASURE

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    AUTOMATIC DETECTION AND CLASSIFICATION OF DEFECT ON ROAD PAVEMENT USING ANISOTROPY MEASURE Tien Sy-sy.nguyen@etu.univ-orleans.fr ABSTRACT Existing systems for automated pavement defect detection can only identify cracking type defects for the inspectors and road users [1]. In the last few years, several automated pavement inspecting systems which use

  1. Permeability of illite-bearing shale: 1. Anisotropy and effects of clay content and loading

    E-Print Network [OSTI]

    Herbert, Bruce

    Permeability of illite-bearing shale: 1. Anisotropy and effects of clay content and loading-rich shale recovered from the Wilcox formation and saturated with 1 M NaCl solution varies from 3 Ã? 10Ã?22 transport; KEYWORDS: permeability, shale, connected pore space Citation: Kwon, O., A. K. Kronenberg, A. F

  2. Magnetic anisotropy in a permalloy microgrid fabricated by near-field optical lithography

    SciTech Connect (OSTI)

    Li, S. P.; Lebib, A.; Peyrade, D.; Natali, M.; Chen, Y.; Lew, W. S.; Bland, J. A. C.

    2001-07-01T23:59:59.000Z

    We report the fabrication and magnetic properties of permalloy microgrids prepared by near-field optical lithography and characterized using high-sensitivity magneto-optical Kerr effect techniques. A fourfold magnetic anisotropy induced by the grid architecture is identified. {copyright} 2001 American Institute of Physics.

  3. Modeling of Substrate-Induced Anisotropy in Through-Plane Thermal Behavior of Polymeric Thin Films

    E-Print Network [OSTI]

    Lee, Jeong-Bong

    Modeling of Substrate-Induced Anisotropy in Through-Plane Thermal Behavior of Polymeric Thin Films, Atlanta, Georgia 30332-0269 SYNOPSIS Polymeric thin films are widely used in microelectronic applications properties of isotropic thin films for single layer (thin film rigidly clamped) and bilayer (thin film

  4. Influence of Tissue Conductivity Inhomogeneity and Anisotropy on EEG/MEG based

    E-Print Network [OSTI]

    Utah, University of

    source in the brain using a volume-conduction model of the head. The associated differential equations in the Human Brain #12;Die Deutsche Bibliothek - CIP-Einheitsaufnahme Wolters, Carsten Hermann: Influence of Tissue Conductivity Inhomogeneity and Anisotropy on EEG/MEG based Source Localization in the Human Brain

  5. The Large Scale Cosmic-Ray Anisotropy as Observed with Milagro

    E-Print Network [OSTI]

    Abdo, A A; Aune, T; Berley, D; Casanova, S; Chen, C; Dingus, B L; Ellsworth, R W; Fleysher, L; Fleysher, R; González, M M; Goodman, J A; Hoffman, C M; Hopper, B; Hüntemeyer, P H; Kolterman, B E; Lansdell, C P; Linnemann, J T; McEnery, J E; Mincer, A I; Némethy, P; Noyes, D; Ryan, J M; Parkinson, P M Saz; Shoup, A; Sinnis, G; Smith, A J; Sullivan, G W; Vasileiou, V; Walker, G P; Williams, D A; Yodh, G B

    2008-01-01T23:59:59.000Z

    Results are presented of a harmonic analysis of the large scale cosmic-ray anisotropy as observed by the Milagro observatory. We show a two-dimensional display of the sidereal anisotropy projections in right ascension generated by the fitting of three harmonics to 18 separate declination bands. The Milagro observatory is a water Cherenkov detector located in the Jemez mountains near Los Alamos, New Mexico. With a high duty cycle and large field-of-view, Milagro is an excellent instrument for measuring this anisotropy with high sensitivity at TeV energies. The analysis is conducted using a seven year data sample consisting of more than 95 billion events. We observe an anisotropy with a magnitude around 0.1% for cosmic rays with a median energy of 6 TeV. The dominant feature is a deficit region of depth (-2.85 +/- 0.06 stat. +/- 0.08 syst.)x10^(-3) in the direction of the Galactic North Pole with a range in declination of -10 to 45 degrees and 150 to 225 degrees in right ascension. We observe a steady increase ...

  6. The Large Scale Cosmic-Ray Anisotropy as Observed with Milagro

    E-Print Network [OSTI]

    A. A. Abdo; B. T. Allen; T. Aune; D. Berley; S. Casanova; C. Chen; B. L. Dingus; R. W. Ellsworth; L. Fleysher; R. Fleysher; M. M. Gonzalez; J. A. Goodman; C. M. Hoffman; B. Hopper; P. H. Hüntemeyer; B. E. Kolterman; C. P. Lansdell; J. T. Linnemann; J. E. McEnery; A. I. Mincer; P. Nemethy; D. Noyes; J. Pretz; J. M. Ryan; P. M. Saz Parkinson; A. Shoup; G. Sinnis; A. J. Smith; G. W. Sullivan; V. Vasileiou; G. P. Walker; D. A. Williams; G. B. Yodh

    2009-04-20T23:59:59.000Z

    Results are presented of a harmonic analysis of the large scale cosmic-ray anisotropy as observed by the Milagro observatory. We show a two-dimensional display of the sidereal anisotropy pro jections in right ascension generated by the fitting of three harmonics to 18 separate declination bands. The Milagro observatory is a water Cherenkov detector located in the Jemez mountains near Los Alamos, New Mexico. With a high duty cycle and large field-of-view, Milagro is an excellent instrument for measuring this anisotropy with high sensitivity at TeV energies. The analysis is conducted using a seven year data sample consisting of more than 95 billion events, the largest such data set in existence. We observe an anisotropy with a magnitude around 0.1% for cosmic rays with a median energy of 6 TeV. The dominant feature is a deficit region of depth (2.49 +/- 0.02 stat. +/- 0.09 sys.)x10^(-3) in the direction of the Galactic North Pole centered at 189 degrees right ascension. We observe a steady increase in the magnitude of the signal over seven years.

  7. Perpendicular magnetic anisotropy in ion beam sputtered Co/Ni multilayers

    E-Print Network [OSTI]

    Rasin, Boris

    2009-01-01T23:59:59.000Z

    Co/Ni multilayers display perpendicular magnetic anisotropy and have applications in magnetic devices that could lead to a large increase in the density of magnetic storage. Co/Ni 10-(2 Å Co/ 8Å Ni) and 10-(2 Å Co/ 4 Å Ni) ...

  8. Secondary dust density waves excited by nonlinear dust acoustic waves

    SciTech Connect (OSTI)

    Heinrich, J. R.; Kim, S.-H.; Meyer, J. K.; Merlino, R. L. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States); Rosenberg, M. [Department of Electrical and Computer Engineering, University of California, San Diego, California 92093 (United States)

    2012-08-15T23:59:59.000Z

    Secondary dust density waves were observed in conjunction with high amplitude (n{sub d}/n{sub d0}>2) dust acoustic waves (DAW) that were spontaneously excited in a dc glow discharge dusty plasma in the moderately coupled, {Gamma}{approx}1, state. The high amplitude dust acoustic waves produced large dust particle oscillations, displacements, and trapping. Secondary dust density waves were excited in the wave troughs of the high amplitude DAWs. The waveforms, amplitudes, wavelengths, and wave speeds of the primary DAWs and the secondary waves were measured. A dust-dust streaming instability is discussed as a possible mechanism for the production of the secondary waves.

  9. Recirculation in multiple wave conversions

    E-Print Network [OSTI]

    Brizard, A.J.

    2008-01-01T23:59:59.000Z

    model lies with the simple wave energy conservation law itthe recirculation of wave energy introduces interference e?particles, the tertiary-wave energy may be negative and thus

  10. Arnold Schwarzenegger CALIFORNIA OCEAN WAVE

    E-Print Network [OSTI]

    Arnold Schwarzenegger Governor CALIFORNIA OCEAN WAVE ENERGY ASSESSMENT Prepared For: California this report as follows: Previsic, Mirko. 2006. California Ocean Wave Energy Assessment. California Energy Systems Integration · Transportation California Ocean Wave Energy Assessment is the final report

  11. Diagonalization of pp-waves

    E-Print Network [OSTI]

    B. V. Ivanov

    1997-05-21T23:59:59.000Z

    A coordinate transformation is found which diagonalizes the axisymmetric pp-waves. Its effect upon concrete solutions, including impulsive and shock waves, is discussed.

  12. Wave-wave interactions in solar type III radio bursts

    SciTech Connect (OSTI)

    Thejappa, G. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); MacDowall, R. J. [NASA/Goddard Space Flight Center, Greenbelt MD 20771 (United States)

    2014-02-11T23:59:59.000Z

    The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.

  13. The interplay of long-range magnetic order and single-ion anisotropy in rare earth nickel germanides

    SciTech Connect (OSTI)

    Islam, Z.

    1999-05-10T23:59:59.000Z

    This dissertation is concerned with the interplay of long-range order and anisotropy in the tetragonal RNi{sub 2}Ge{sub 2} (R = rare earth) family of compounds. Microscopic magnetic structures were studied using both neutron and x-ray resonant exchange scattering (XRES) techniques. The magnetic structures of Tb, Dy, Eu and Gd members have been determined using high-quality single-crystal samples. This work has correlated a strong Fermi surface nesting to the magnetic ordering in the RNi{sub 2}Ge{sub 2} compounds. Generalized susceptibility, {chi}{sub 0}(q), calculations found nesting to be responsible for both incommensurate ordering wave vector in GdNi{sub 2}Ge{sub 2}, and the commensurate structure in EuNi{sub 2}Ge{sub 2}. A continuous transition from incommensurate to commensurate magnetic structures via band filling is predicted. The surprisingly higher T{sub N} in EuNi{sub 2}Ge{sub 2} than that in GdNi{sub 2}Ge{sub 2} is also explained. Next, all the metamagnetic phases in TbNi{sub 2}Ge{sub 2} with an applied field along the c axis have been characterized with neutron diffraction measurements. A mixed phase model for the first metamagnetic structure consisting of fully-saturated as well as reduced-moment Tb ions is presented. The moment reduction may be due to moment instability which is possible if the exchange is comparable to the low-lying CEF level splitting and the ground state is a singlet. In such a case, certain Tb sites may experience a local field below the critical value needed to reach saturation.

  14. Full wave simulations of lower hybrid wave propagation in tokamaks

    E-Print Network [OSTI]

    Wright, John C.

    Full wave simulations of lower hybrid wave propagation in tokamaks J. C. Wright , P. T. Bonoli , C hybrid (LH) waves have the attractive property of damping strongly via electron Landau resonance. Consequently these waves are well-suited to driving current in the plasma periphery where the electron

  15. Spin-waves in antiferromagnetic single-crystal LiFePO4 Jiying Li,* Vasile O. Garlea, Jerel L. Zarestky, and David Vaknin

    E-Print Network [OSTI]

    Vakni, David

    -wave theory by including in the spin Hamiltonian in-plane nearest- and next-nearest-neighbor interactions J1 and J2 , inter-plane nearest-neighbor interactions J and a single-ion anisotropy D . A weak 0 number s : 75.25. z, 75.30.Ds, 75.50.Ee I. INTRODUCTION Lithium-orthophosphates LiMPO4 M=Mn,Fe,Co,Ni have

  16. Wind Wave Float

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

    Water Power Peer Review WindWaveFloat Alla Weinstein Principle Power, Inc. aweinstein@principlepowerinc.com November 1, 2011 2 | Wind and Water Power Program eere.energy.gov...

  17. Waving in the rain

    E-Print Network [OSTI]

    Cavaleri, Luigi; Bidlot, Jean-Raymond

    2015-01-01T23:59:59.000Z

    We consider the effect of rain on wind wave generation and dissipation. Rain falling on a wavy surface may have a marked tendency to dampen the shorter waves in the tail of the spectrum, the related range increasing with the rain rate. Following the coupling between meteorological and wave models, we derive that on the whole this should imply stronger wind and higher waves in the most energetic part of the spectrum. This is supported by numerical experiments. However, a verification based on the comparison between operational model results and measured data suggests that the opposite is true. This leads to a keen analysis of the overall process, in particular on the role of the tail of the spectrum in modulating the wind input and the white-capping. We suggest that the relationship between white-capping and generation by wind is deeper and more implicative than presently generally assumed.

  18. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, V.M.; Vawter, G.A.

    1993-12-14T23:59:59.000Z

    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.

  19. Surface wave interferometry 

    E-Print Network [OSTI]

    Halliday, David Fraser

    2009-01-01T23:59:59.000Z

    This thesis concerns the application of seismic interferometry to surface waves. Seismic interferometry is the process by which the wavefield between two recording locations is estimated, resulting in new recordings at ...

  20. Millimeter-wave sensors

    E-Print Network [OSTI]

    Kim, Seoktae

    2006-04-12T23:59:59.000Z

    New millimeter wave interferometric, multifunctional sensors have been studied for industrial sensing applications: displacement measurement, liquid-level gauging and velocimetry. Two types of configuration were investigated to implement the sensor...

  1. Pilot-wave hydrodynamics

    E-Print Network [OSTI]

    Bush, John W. M.

    Yves Couder, Emmanuel Fort, and coworkers recently discovered that a millimetric droplet sustained on the surface of a vibrating fluid bath may self-propel through a resonant interaction with its own wave field. This article ...

  2. The effect of broad-band Alfven-cyclotron waves spectra on the preferential heating and differential acceleration of He{sup ++} ions in the solar wind

    SciTech Connect (OSTI)

    Maneva, Y. G. [Department of Physics, Catholic University of America, Washington DC, 20064 (United States) and Heliophysics Science Devision, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Ofman, L. [Department of Physics, Catholic University of America, Washington, DC 20064 (United States) and Heliophysics Science Devision, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Vinas, A. F. [Heliophysics Science Devision, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2013-06-13T23:59:59.000Z

    In anticipation of results from inner heliospheric missions such as the Solar Orbiter and the Solar Probe we present the results from 1.5D hybrid simulations to study the role of magnetic fluctuations for the heating and differential acceleration of He{sup ++} ions in the solar wind. We consider the effects of nonlinear Alfven-cyclotron waves at different frequency regimes. Monochromatic nonlinear Alfven-alpha-cyclotron waves are known to preferentially heat and accelerate He{sup ++} ions in collisionless low beta plasma. In this study we demonstrate that these effects are preserved when higherfrequency monochromatic and broad-band spectra of Alfven-proton-cyclotron waves are considered. Comparison between several nonlinear monochromatic waves shows that the ion temperatures, anisotropies and relative drift are quantitatively affected by the shift in frequency. Including a broad-band wave-spectrum results in a significant reduction of both the parallel and the perpendicular temperature components for the He{sup ++} ions, whereas the proton heating is barely influenced, with the parallel proton temperature only slightly enhanced. The differential streaming is strongly affected by the available wave power in the resonant daughter ion-acoustic waves. Therefore for the same initial wave energy, the relative drift is significantly reduced in the case of initial wave-spectra in comparison to the simulations with monochromatic waves.

  3. Autoresonant Excitation of Diocotron Waves

    E-Print Network [OSTI]

    Wurtele, Jonathan

    of the wave, the pump and the wave will phase lock at very low wave amplitude. When the pump reachesAutoresonant Excitation of Diocotron Waves J. Fajans E. Gilson U.C. Berkeley L. Friedland Hebrew of phase with the oscillator, and the os- cillator's amplitude will decrease, eventually reaching zero

  4. Interfacial oxygen migration and its effect on the magnetic anisotropy in Pt/Co/MgO/Pt films

    SciTech Connect (OSTI)

    Chen, Xi; Feng, Chun, E-mail: fengchun@ustb.edu.cn, E-mail: ghyu@mater.ustb.edu.cn; Liu, Yang; Jiang, Shaolong; Hua Li, Ming; Hua Yu, Guang, E-mail: fengchun@ustb.edu.cn, E-mail: ghyu@mater.ustb.edu.cn [Department of Materials Physics and Chemistry, University of Science and Technology Beijing, Beijing 100083 (China); Long Wu, Zheng [Analytical and Testing Center, Beijing Normal University, Beijing 100875 (China); Yang, Feng [State Key Laboratory of Heavy Oil Processing, China University of Petroleum, Beijing 102249 (China)

    2014-02-03T23:59:59.000Z

    This paper reports the interfacial oxygen migration effect and its induced magnetic anisotropy evolution in Pt/Co/MgO/Pt films. During depositing the MgO layer, oxygen atoms from the MgO combine with the neighboring Co atoms, leading to the formation of CoO at the Co/MgO interface. Meanwhile, the films show in-plane magnetic anisotropy (IMA). After annealing, most of the oxygen atoms in CoO migrate back to the MgO layer, resulting in obvious improvement of Co/MgO interface and the enhancement of effective Co-O orbital hybridization. These favor the evolution of magnetic anisotropy from IMA to perpendicular magnetic anisotropy (PMA). The oxygen migration effect is achieved by the redox reaction at the Co/MgO interface. On the contrary, the transfer from IMA to PMA cannot be observed in Pt/Co/Pt films due to the lack of interfacial oxygen migration.

  5. Local control of magnetocrystalline anisotropy in (Ga,Mn)As microdevices: Demonstration in current-induced switching

    E-Print Network [OSTI]

    Wunderlich, J.; Irvine, A. C.; Zemen, J.; Holy, V.; Rushforth, A. W.; De Ranieri, E.; Rana, U.; Vyborny, K.; Sinova, Jairo; Foxon, C. T.; Campion, R. P.; Williams, D. A.; Gallagher, B. L.; Jungwirth, T.

    2007-01-01T23:59:59.000Z

    The large saturation magnetization in conventional dense moment ferromagnets offers a flexible means of manipulating the ordered state through demagnetizing shape anisotropy fields, but these dipolar fields, in turn, limit the integrability...

  6. Visualization of microcrack anisotropy in granite affected by afault zone, using confocal laser scanning microscope

    SciTech Connect (OSTI)

    Onishi, Celia T.; Shimizu, Ichiko

    2004-01-02T23:59:59.000Z

    Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation.

  7. Constraints on CPT violation from Wilkinson Microwave Anisotropy Probe three year polarization data: A wavelet analysis

    SciTech Connect (OSTI)

    Cabella, Paolo; Silk, Joseph [University of Oxford, Astrophysics, Keble Road, Oxford, OX1 3RH (United Kingdom); Natoli, Paolo [Dipartimento di Fisica e sezione INFN, Universita di Roma 'Tor Vergata', Via della Ricerca Scientifica, I-00133 Rome (Italy)

    2007-12-15T23:59:59.000Z

    We perform a wavelet analysis of the temperature and polarization maps of the cosmic microwave background (CMB) delivered by the Wilkinson Microwave Anisotropy Probe experiment in search for a parity-violating signal. Such a signal could be seeded by new physics beyond the standard model, for which the Lorentz and CPT symmetries may not hold. Under these circumstances, the linear polarization direction of a CMB photon may get rotated during its cosmological journey, a phenomenon also called cosmological birefringence. Recently, Feng et al. have analyzed a subset of the Wilkinson Microwave Anisotropy Probe and BOOMERanG 2003 angular power spectra of the CMB, deriving a constraint that mildly favors a nonzero rotation. By using wavelet transforms we set a tighter limit on the CMB photon rotation angle {delta}{alpha}=-2.5{+-}3.0 ({delta}{alpha}=-2.5{+-}6.0) at the one (two) {sigma} level, consistent with a null detection.

  8. Sputtering of cobalt film with perpendicular magnetic anisotropy on disorder-free graphene

    SciTech Connect (OSTI)

    Jamali, Mahdi; Lv, Yang; Zhao, Zhengyang; Wang, Jian-Ping, E-mail: jpwang@umn.edu [Department of Electrical and Computer Engineering, University of Minnesota, 4-174 200 Union Street SE, Minneapolis, MN 55455 (United States)

    2014-10-15T23:59:59.000Z

    Growth of thin cobalt film with perpendicular magnetic anisotropy has been investigated on pristine graphene for spin logic and memory applications. By reduction of the kinetic energy of the sputtered atoms using indirect sputtered deposition, deposition induced defects in the graphene layer have been controlled. Cobalt film on graphene with perpendicular magnetic anisotropy has been developed. Raman spectroscopy of the graphene surface shows very little disorder induced in the graphene by the sputtering process. In addition, upon increasing the cobalt film thickness, the disorder density increases on the graphene and saturates for thicknesses of Co layers above 1 nm. The AFM image indicates a surface roughness of about 0.86 nm. In addition, the deposited film forms a granular structure with a grain size of about 40 nm.

  9. Three-terminal magnetic tunneling junction device with perpendicular anisotropy CoFeB sensing layer

    SciTech Connect (OSTI)

    Honjo, H., E-mail: hr-honjou@aist.go.jp; Nebashi, R.; Tokutome, K.; Miura, S.; Sakimura, N.; Sugibayashi, T. [Green Platform Research Laboratories, NEC Corporation, Tsukuba (Japan); Fukami, S.; Kinoshita, K.; Murahata, M.; Kasai, N. [Center for Spintronics Integrated Systems, Tohoku University, Sendai (Japan); Ishihara, K. [Smart Energy Research Laboratories, NEC Corporation, Tsukuba (Japan); Ohno, H. [Center for Spintronics Integrated Systems, Tohoku University, Sendai (Japan); Laboratory for Nanoelectronics and Spintronics, Research Institute of Electrical Communication, Tohoku University, Sendai (Japan); WPI Advanced Institute for Materials Research, Tohoku University, Sendai (Japan)

    2014-05-07T23:59:59.000Z

    We demonstrated read and write characteristics of a three terminal memory device with a perpendicular anisotropy-free layer of a strip of [Co/Ni] and a low-switching perpendicular-anisotropy CoFeB/MgO sensing layer. This new design of the cell results in a small cell area. The switching magnetic field of the sensing layer can be decreased by changing sputtering gas for the Ta-cap from Ar to Kr. An electron energy-loss spectroscopy analysis of the cross-section of the magnetic tunneling junction (MTJ) revealed that the boron content in CoFeB with a Kr-sputtered Ta-cap was smaller than that with an Ar-sputtered one. A change in resistance for the MTJ was observed that corresponded to the magnetic switching of the Co/Ni wire and its magnetoresistance ratio and critical current were 90% and 0.8?mA, respectively.

  10. Perpendicular magnetic anisotropy in epitaxially strained cobalt-ferrite (001) thin films

    SciTech Connect (OSTI)

    Yanagihara, H., E-mail: yanagiha@bk.tsukuba.ac.jp; Utsumi, Y.; Niizeki, T., E-mail: t-niizeki@imr.tohoku.ac.jp; Inoue, J.; Kita, Eiji [Institute of Applied Physics, University of Tsukuba, Tsukuba 305-8573 (Japan)

    2014-05-07T23:59:59.000Z

    We investigated the dependencies of both the magnetization characteristics and the perpendicular magnetic anisotropy of Co{sub x}Fe{sub 3–x}O{sub 4}(001) epitaxial films (x?=?0.5 and 0.75) on the growth conditions of the reactive magnetron sputtering process. Both saturation magnetization and the magnetic uniaxial anisotropy constant K{sub u} are strongly dependent on the reactive gas (O{sub 2}) flow rate, although there is little difference in the surface structures for all samples observed by reflection high-energy electron diffraction. In addition, certain dead-layer-like regions were observed in the initial stage of the film growth for all films. Our results suggest that the magnetic properties of Co{sub x}Fe{sub 3–x}O{sub 4} epitaxial films are governed by the oxidation state and the film structure at the vicinity of the interface.

  11. Approach to fabricating Co nanowire arrays with perpendicular anisotropy: Application of a magnetic field during deposition

    SciTech Connect (OSTI)

    Ge, Shihui; Li, Chao; Ma, Xiao; Li, Wei; Xi, Li; Li, C. X.

    2001-07-01T23:59:59.000Z

    Cobalt (Co) nanowire arrays were electrodeposited into the pores of polycarbonate membranes. A magnetic field parallel or perpendicular to the membrane plane was applied during deposition to control the wire growth. X-ray diffraction, transmission electron microscopy, and vibrating sample magnetometer were employed to investigate the structure as well as the magnetic properties of the nanowire arrays. The results show that the magnetic field applied during deposition strongly influences the growth of Co nanowires, inducing variations in their crystalline structure and magnetic properties. The sample deposited with the field perpendicular to the membrane plane exhibits a perpendicular magnetic anisotropy with greatly enhanced coercivity and squareness as a result of the preferred growth of Co grains with the c axis perpendicular to the film plane. In contrast, the deposition in a parallel magnetic field forces Co grains to grow with the c axis parallel to the film plane, resulting in in-plane anisotropy. {copyright} 2001 American Institute of Physics.

  12. Primordial torsion fields as an explanation of the anisotropy in cosmological electromagnetic propagation

    E-Print Network [OSTI]

    Antonio Dobado; Antonio L. Maroto

    1997-07-18T23:59:59.000Z

    In this note we provide a simple explanation of the recent finding of anisotropy in electromagnetic (EM) propagation claimed by Nodland and Ralston (astro-ph/9704196). We consider, as a possible origin of such effect, the effective coupling between EM fields and some tiny background torsion field. The coupling is obtained after integrating out charged fermions, it is gauge invariant and does not require the introduction of any new physics.

  13. Anisotropy of the primary cosmic-ray flux in Super-Kamiokande

    E-Print Network [OSTI]

    Yuichi Oyama

    2006-05-08T23:59:59.000Z

    A first-ever 2-dimensional celestial map of primary cosmic-ray flux was obtained from 2.10x10^8 cosmic-ray muons accumulated in 1662.0 days of Super-Kamiokande. The celestial map indicates an (0.104 \\pm 0.020)% excess region in the constellation of Taurus and a -(0.094 \\pm 0.014)% deficit region toward Virgo. Interpretations of this anisotropy are discussed.

  14. Process and apparatus for preparing textured crystalline materials using anisotropy in the paramagnetic susceptibility

    DOE Patents [OSTI]

    Holloway, A.

    1992-01-07T23:59:59.000Z

    The present invention discloses a process and apparatus for forming textures in materials. The process comprises heating a material having an anisotropy in the paramagnetic or diamagnetic susceptibility within a magnetic field. The material is heated to a temperature approaching its melting point while a magnetic field of at least 10[sup 4]Oe is simultaneously applied. The process and apparatus produce highly textured bulk and elongated materials with high current densities below critical superconducting temperatures. 6 figs.

  15. Process and apparatus for preparing textured crystalline materials using anisotropy in the paramagnetic susceptibility

    DOE Patents [OSTI]

    Holloway, Aleksey (522 N. 32nd St., Omaha, NE 68131)

    1992-01-07T23:59:59.000Z

    The present invention discloses a process and apparatus for forming textures in materials. The process comprises heating a material having an anisotropy in the paramagnetic or diamagnetic susceptibility within a magnetic field. The material is heated to a temperature approaching its melting point while a magnetic field of at least 10.sup.4 Oe is simultaneously applied. The process and apparatus produce highly textured bulk and elongated materials with high current densities below critical superconducting temperatures.

  16. On the Observation of the Cosmic Ray Anisotropy below 10$^{15}$ eV

    E-Print Network [OSTI]

    G. Di Sciascio; R. Iuppa

    2014-07-08T23:59:59.000Z

    The measurement of the anisotropy in the arrival direction of cosmic rays is complementary to the study of their energy spectrum and chemical composition to understand their origin and propagation. It is also a tool to probe the structure of the magnetic fields through which cosmic rays travel. As cosmic rays are mostly charged nuclei, their trajectories are deflected by the action of galactic magnetic field they propagate through before reaching the Earth atmosphere, so that their detection carries directional information only up to distances as large as their gyro-radius. If cosmic rays below $10^{15}{\\rm\\,eV}$ are considered and the local galactic magnetic field ($\\sim3{\\rm\\,\\mu G}$) is accounted for, gyro-radii are so short that isotropy is expected. At most, a weak di-polar distribution may exist, reflecting the contribution of the closest CR sources. However, a number of experiments observed an energy-dependent \\emph{"large scale"} anisotropy in the sidereal time frame with an amplitude of about 10$^{-4}$ - 10$^{-3}$, revealing the existence of two distinct broad regions: an excess distributed around 40$^{\\circ}$ to 90$^{\\circ}$ in Right Ascension (commonly referred to as "tail.in" excess) and a deficit (the "loss cone") around 150$^{\\circ}$ to 240$^{\\circ}$ in Right Ascension. In recent years the Milagro and ARGO-YBJ collaborations reported the of a "medium" scale anisotropy inside the tail-in region. The observation of such small features has been recently claimed by the IceCube experiment also in the Southern hemisphere. So far, no theory of cosmic rays in the Galaxy exists which is able to explain the origin of these different anisotropies leaving the standard model of cosmic rays and that of the galactic magnetic field unchanged at the same time.

  17. Study of anisotropy of spin cast and vapor deposited polyimide films using internal reflection techniques

    SciTech Connect (OSTI)

    Liberman, V.

    1996-11-01T23:59:59.000Z

    We have compared anisotropy of spin cast and vapor deposited polyimide (VDP) films, using internal reflection infrared spectroscopy. The films were deposited directly on the internal reflection element. We find that spin cast films are more anisotropic than their VDP counterparts, with the polyimide chains tending to align parallel to the substrate. Both films are found to contain more and less ordered regions. Within the ordered regions, the plane of the phenyl ring tends to align parallel to the substrate.

  18. Analysis of stress-induced Burgers vector anisotropy in pressurized tube specimens of irradiated ferritic-martensitic steel: JLF-1

    SciTech Connect (OSTI)

    Gelles, D.S. [Pacific Northwest National Lab., Richland, WA (United States); Shibayama, T. [Univ. of Hokkaido, Oarai, Ibaraki (Japan). Inst. for Materials Research

    1998-09-01T23:59:59.000Z

    A procedure for determining the Burgers vector anisotropy in irradiated ferritic steels allowing identification of all a<100> and all a/2<111> dislocations in a region of interest is applied to a pressurized tube specimen of JLF-1 irradiated at 430 C to 14.3 {times} 10{sup 22} n/cm{sup 2} (E > 0.1 MeV) or 61 dpa. Analysis of micrographs indicates large anisotropy in Burgers vector populations develop during irradiation creep.

  19. Magnetic anisotropy barrier for spin tunneling in Mn{sub 12}O{sub 12} molecules

    SciTech Connect (OSTI)

    Pederson, M.R. [Center for Computational Materials Science--6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science--6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Khanna, S.N. [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)] [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)

    1999-10-01T23:59:59.000Z

    Electronic structure calculations on the nature of electronic states and the magnetic coupling in Mn-acetate [Mn{sub 12}O{sub 12}(RCOO){sub 16}(H{sub 2}O){sub 4}] molecules have been been carried out within the generalized gradient approximation to the density functional formalism. Our studies on this 100-atom molecule illustrate the role of the nonmagnetic carboxyl host in stabilizing the ferrimagnetic Mn{sub 12}O{sub 12} core and provide estimates of the local magnetic moment at the various sites. We provide a first density-functional-based prediction of the second-order magnetic anisotropy energy of this system. Results are in excellent agreement with experiment. To perform these calculations we introduce a simplified exact method for spin-orbit coupling and magnetic anisotropy energies in multicenter systems. This method is free of shape approximations and has other advantages as well. First, it is valid for periodic boundary conditions or finite systems and is independent of basis set choice. Second, the method does not require the calculation of electric field. Third, for applications to systems with a finite energy gap between occupied and unoccupied electronic states, a perturbative expansion allows for a simple determination of the magnetic anisotropy energy. {copyright} {ital 1999} {ital The American Physical Society}

  20. Theoretical calculations of magnetic order and anisotropy energies in molecular magnets

    SciTech Connect (OSTI)

    Pederson, M. R. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Porezag, D. V. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Kortus, J. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Khanna, S. N. [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)] [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)

    2000-05-01T23:59:59.000Z

    We present theoretical electronic structure calculations on the nature of electronic states and the magnetic coupling in the Mn{sub 12}O{sub 12} free cluster and the Mn{sub 12}O{sub 12}(RCOO){sub 16}(H{sub 2}O){sub 4} molecular magnetic crystal. The calculations have been performed with the all-electron full-potential NRLMOL code. We find that the free Mn{sub 12}O{sub 12} cluster relaxes to an antiferromagnetic cluster with no net moment. However, when coordinated by sixteen HCOO ligands and four H{sub 2}O groups, as it is in the molecular crystal, we find that the ferrimagnetic ordering and geometrical and magnetic structure observed in the experiments is restored. Local Mn moments for the free and ligandated molecular magnets are presented and compared to experiment. We identify the occupied and unoccupied electronic states that are most responsible for the formation of the large anisotropy barrier and use a recently developed full-space and full-potential method for calculating the spin-orbit coupling interaction and anisotropy energies. Our calculated second-order anisotropy energy is in excellent agreement with experiment. (c) 2000 American Institute of Physics.

  1. OBSERVATION OF COSMIC-RAY ANISOTROPY WITH THE ICETOP AIR SHOWER ARRAY

    SciTech Connect (OSTI)

    Aartsen, M. G. [School of Chemistry and Physics, University of Adelaide, Adelaide, SA 5005 Australia (Australia)] [School of Chemistry and Physics, University of Adelaide, Adelaide, SA 5005 Australia (Australia); Abbasi, R.; Ahlers, M.; Andeen, K.; Auffenberg, J.; Baker, M. [Department of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI 53706 (United States)] [Department of Physics and Wisconsin IceCube Particle Astrophysics Center, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium)] [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Ackermann, M. [DESY, D-15735 Zeuthen (Germany)] [DESY, D-15735 Zeuthen (Germany); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand)] [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Aguilar, J. A. [Departement de physique nucleaire et corpusculaire, Universite de Geneve, CH-1211 Geneve (Switzerland)] [Departement de physique nucleaire et corpusculaire, Universite de Geneve, CH-1211 Geneve (Switzerland); Altmann, D. [Institut fuer Physik, Humboldt-Universitaet zu Berlin, D-12489 Berlin (Germany)] [Institut fuer Physik, Humboldt-Universitaet zu Berlin, D-12489 Berlin (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States)] [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States)] [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Baum, V. [Institute of Physics, University of Mainz, Staudinger Weg 7, D-55099 Mainz (Germany)] [Institute of Physics, University of Mainz, Staudinger Weg 7, D-55099 Mainz (Germany); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States)] [Department of Physics, University of California, Berkeley, CA 94720 (United States); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)] [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States)] [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Science Faculty CP230, Universite Libre de Bruxelles, B-1050 Brussels (Belgium)] [Science Faculty CP230, Universite Libre de Bruxelles, B-1050 Brussels (Belgium); Tjus, J. Becker [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)] [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Becker, K.-H. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany)] [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Collaboration: IceCube Collaboration; and others

    2013-03-01T23:59:59.000Z

    We report on the observation of anisotropy in the arrival direction distribution of cosmic rays at PeV energies. The analysis is based on data taken between 2009 and 2012 with the IceTop air shower array at the south pole. IceTop, an integral part of the IceCube detector, is sensitive to cosmic rays between 100 TeV and 1 EeV. With the current size of the IceTop data set, searches for anisotropy at the 10{sup -3} level can, for the first time, be extended to PeV energies. We divide the data set into two parts with median energies of 400 TeV and 2 PeV, respectively. In the low energy band, we observe a strong deficit with an angular size of about 30 Degree-Sign and an amplitude of (- 1.58 {+-} 0.46{sub stat} {+-} 0.52{sub sys}) Multiplication-Sign 10{sup -3} at a location consistent with previous observations of cosmic rays with the IceCube neutrino detector. The study of the high energy band shows that the anisotropy persists to PeV energies and increases in amplitude to (- 3.11 {+-} 0.38{sub stat} {+-} 0.96{sub sys}) Multiplication-Sign 10{sup -3}.

  2. Nonlinear Evolution of Cosmic Magnetic Fields and Cosmic Microwave Background Anisotropies

    E-Print Network [OSTI]

    Hiroyuki Tashiro; Naoshi Sugiyama; Robi Banerjee

    2006-01-14T23:59:59.000Z

    In this work we investigate the effects of the primordial magnetic fields on cosmic microwave background anisotropies (CMB). Based on cosmological magnetohydrodynamic (MHD) simulations we calculate the CMB anisotropy spectra and polarization induced by fluid fluctuations (Alfv\\'en modes) generated by primordial magnetic fields. The strongest effect on the CMB spectra comes from the transition epoch from a turbulent regime to a viscous regime. The balance between magnetic and kinetic energy until the onset of the viscous regime provides a one to one relation between the comoving coherence length $L$ and the comoving magnetic field strength $B$, such as $L \\sim 30 (B/10^{-9}{\\rm G})^3 \\rm pc$. The resulting CMB temperature and polarization anisotropies are somewhat different from the ones previously obtained by using linear perturbation theory. Our calculation gives a constraint on the magnetic field strength in the intermediate scale of CMB observations. Upper limits are set by WMAP and BOOMERANG results for comoving magnetic field strength of $B 0.7 \\rm Mpc$ for the most extreme case, or $B 0.8 \\rm Mpc$ for the most conservative case.

  3. The Effect of Proton Temperature Anisotropy on the Solar Minimum Corona and Wind

    E-Print Network [OSTI]

    Alberto M. Vasquez; Adriaan A. van Ballegooijen; John C. Raymond

    2003-10-29T23:59:59.000Z

    A semi-empirical, axisymmetric model of the solar minimum corona is developed by solving the equations for conservation of mass and momentum with prescribed anisotropic temperature distributions. In the high-latitude regions, the proton temperature anisotropy is strong and the associated mirror force plays an important role in driving the fast solar wind; the critical point where the outflow velocity equals the parallel sound speed is reached already at 1.5 Rsun from Sun center. The slow wind arises from a region with open field lines and weak anisotropy surrounding the equatorial streamer belt. The model parameters were chosen to reproduce the observed latitudinal extent of the equatorial streamer in the corona and at large distance from the Sun. We find that the magnetic cusp of the closed-field streamer core lies at about 1.95 Rsun. The transition from fast to slow wind is due to a decrease in temperature anisotropy combined with the non-monotonic behavior of the non-radial expansion factor in flow tubes that pass near the streamer cusp. In the slow wind, the plasma beta is of order unity and the critical point lies at about 5 Rsun, well beyond the magnetic cusp. The predicted outflow velocities are consistent with OVI Doppler dimming measurements from UVCS/SOHO. We also find good agreement with polarized brightness (pB) measurements from LASCO/SOHO and HI Ly-alpha images from UVCS/SOHO.

  4. Re-Analysis of the Marinov Light-Speed Anisotropy Experiment

    E-Print Network [OSTI]

    Reginald T Cahill

    2007-01-02T23:59:59.000Z

    The anisotropy of the speed of light at 1 part in 10^3 has been detected by Michelson and Morley (1887), Miller (1925/26), Illingworth (1927), Joos (1930), Jaseja et al. (1964), Torr and Kolen (1984), De Witte (1991) and Cahill (2006) using a variety of experimental techniques, from gas-mode Michelson interferometers (with the relativistic theory for these only determined in 2002) to one-way RF coaxial cable propagation timing. All agree on the speed, right ascension and declination of the anisotropy velocity. The Stephan Marinov experiment (1984) detected a light speed anisotropy using a mechanical coupled shutters technique which has holes in co-rotating disks, essentially a one-way version of the Fizeau mechanical round-trip speed-of-light experiment. The Marinov data is re-analysed herein because the velocity vector he determined is in a very different direction to that from the above experiments. No explanation for this difference has been uncovered.

  5. Most spin-1/2 transition-metal ions do have single ion anisotropy

    SciTech Connect (OSTI)

    Liu, Jia; Whangbo, Myung-Hwan, E-mail: hxiang@fudan.edu.cn, E-mail: mike-whangbo@ncsu.edu [Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695 (United States); Koo, Hyun-Joo [Department of Chemistry and Research Institute for Basic Sciences, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Xiang, Hongjun, E-mail: hxiang@fudan.edu.cn, E-mail: mike-whangbo@ncsu.edu [Key Laboratory of Computational Physical Sciences (Ministry of Education), State Key Laboratory of Surface Physics, and Department of Physics, Fudan University, Shanghai 200433 (China); Kremer, Reinhard K. [Max-Planck-Institut für Festkörperforschung, Heisenbergstrasse 1, D-70569 Stuttgart (Germany)

    2014-09-28T23:59:59.000Z

    The cause for the preferred spin orientation in magnetic systems containing spin-1/2 transition-metal ions was explored by studying the origin of the easy-plane anisotropy of the spin-1/2 Cu{sup 2+} ions in CuCl{sub 2}·2H{sub 2}O, LiCuVO{sub 4}, CuCl{sub 2}, and CuBr{sub 2} on the basis of density functional theory and magnetic dipole-dipole energy calculations as well as a perturbation theory treatment of the spin-orbit coupling. We find that the spin orientation observed for these spin-1/2 ions is not caused by their anisotropic spin exchange interactions, nor by their magnetic dipole-dipole interactions, but by the spin-orbit coupling associated with their crystal-field split d-states. Our study also predicts in-plane anisotropy for the Cu{sup 2+} ions of Bi{sub 2}CuO{sub 4} and Li{sub 2}CuO{sub 2}. The results of our investigations dispel the mistaken belief that magnetic systems with spin-1/2 ions have no magnetic anisotropy induced by spin-orbit coupling.

  6. Effects of pressure anisotropy on magnetospheric magnetohydrodynamics equilibrium of an internal ring current system

    SciTech Connect (OSTI)

    Furukawa, M., E-mail: furukawa@damp.tottori-u.ac.jp [Graduate School of Engineering, Tottori University, Tottori 680-8552 (Japan)

    2014-01-15T23:59:59.000Z

    Effects of pressure anisotropy on magnetospheric magnetohydrodynamics equilibrium are studied analytically and numerically, where the plasma is confined by only poloidal magnetic field generated by an internal ring current. The plasma current due to finite pressure can be divided into two components; one remains at isotropic pressure and the other arises from pressure anisotropy. When p{sub ?}, the pressure perpendicular to the magnetic field, is larger than p{sub ?}, the pressure parallel to the magnetic field, those two components of plasma current tend to cancel each other to reduce the total amount of plasma current. Equilibrium beta limit is also examined, where the beta is a ratio of the plasma pressure to the magnetic pressure. The equilibrium beta limit decreases as the pressure anisotropy becomes strong. The beta value is strictly limited by ellipticity of the equilibrium equation when p{sub ?}>p{sub ?}. On the other hand, when p{sub ?}>p{sub ?}, although the tendency of the beta limit agrees with the ellipticity condition of the equilibrium equation, equilibria with a hyperbolic region can be obtained by iterative procedure with practically reasonable convergence criteria.

  7. Fermi-LAT gamma-ray anisotropy and intensity explained by unresolved Radio-Loud Active Galactic Nuclei

    E-Print Network [OSTI]

    Mattia Di Mauro; Alessandro Cuoco; Fiorenza Donato; Jennifer M. Siegal-Gaskins

    2014-12-02T23:59:59.000Z

    Radio-loud active galactic nuclei (AGN) are expected to contribute substantially to both the intensity and anisotropy of the isotropic gamma-ray background (IGRB). In turn, the measured properties of the IGRB can be used to constrain the characteristics of proposed contributing source classes. We consider individual subclasses of radio-loud AGN, including low-, intermediate-, and high-synchrotron-peaked BL Lacertae objects, flat-spectrum radio quasars, and misaligned AGN. Using updated models of the gamma-ray luminosity functions of these populations, we evaluate the energy-dependent contribution of each source class to the intensity and anisotropy of the IGRB. We find that collectively radio-loud AGN can account for the entirety of the IGRB intensity and anisotropy as measured by the Fermi Large Area Telescope (LAT). Misaligned AGN provide the bulk of the measured intensity but a negligible contribution to the anisotropy, while high-synchrotron-peaked BL Lacertae objects provide the dominant contribution to the anisotropy. In anticipation of upcoming measurements with the Fermi-LAT and the forthcoming Cherenkov Telescope Array, we predict the anisotropy in the broader energy range that will be accessible to future observations.

  8. CX-011384: Categorical Exclusion Determination | Department of...

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

    Categorical Exclusion Determination Advanced Controls for the Multi-pod Centipod Wave Energy Converter Device CX(s) Applied: A9 Date: 12022013 Location(s): California...

  9. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1988-03-08T23:59:59.000Z

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 4 figs.

  10. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1987-03-12T23:59:59.000Z

    An explosive plane-wave air lens which enables a spherical wave form to be converted to a planar wave without the need to specially machine or shape explosive materials is described. A disc-shaped impactor having a greater thickness at its center than around its periphery is used to convert the spherical wave into a plane wave. When the wave reaches the impactor, the center of the impactor moves first because the spherical wave reaches the center of the impactor first. The wave strikes the impactor later in time as one moves radially along the impactor. Because the impactor is thinner as one moves radially outward, the velocity of the impactor is greater at the periphery than at the center. An acceptor explosive is positioned so that the impactor strikes the acceptor simultaneously. Consequently, a plane detonation wave is propagated through the acceptor explosive. 3 figs., 3 tabs.

  11. Formation of electron kappa distributions due to interactions with parallel propagating whistler waves

    SciTech Connect (OSTI)

    Tao, X., E-mail: xtao@ustc.edu.cn; Lu, Q. [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China) [CAS Key Laboratory of Geospace Environment, Department of Geophysics and Planetary Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Mengcheng National Geophysical Observatory, School of Earth and Space Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2014-02-15T23:59:59.000Z

    In space plasmas, charged particles are frequently observed to possess a high-energy tail, which is often modeled by a kappa-type distribution function. In this work, the formation of the electron kappa distribution in generation of parallel propagating whistler waves is investigated using fully nonlinear particle-in-cell (PIC) simulations. A previous research concluded that the bi-Maxwellian character of electron distributions is preserved in PIC simulations. We now demonstrate that for interactions between electrons and parallel propagating whistler waves, a non-Maxwellian high-energy tail can be formed, and a kappa distribution can be used to fit the electron distribution in time-asymptotic limit. The ?-parameter is found to decrease with increasing initial temperature anisotropy or decreasing ratio of electron plasma frequency to cyclotron frequency. The results might be helpful to understanding the origin of electron kappa distributions observed in space plasmas.

  12. IR Hot Wave

    SciTech Connect (OSTI)

    Graham, T. B.

    2010-04-01T23:59:59.000Z

    The IR Hot Wave{trademark} furnace is a breakthrough heat treatment system for manufacturing metal components. Near-infrared (IR) radiant energy combines with IR convective heating for heat treating. Heat treatment is an essential process in the manufacture of most components. The controlled heating and cooling of a metal or metal alloy alters its physical, mechanical, and sometimes chemical properties without changing the object's shape. The IR Hot Wave{trademark} furnace offers the simplest, quickest, most efficient, and cost-effective heat treatment option for metals and metal alloys. Compared with other heat treatment alternatives, the IR Hot Wave{trademark} system: (1) is 3 to 15 times faster; (2) is 2 to 3 times more energy efficient; (3) is 20% to 50% more cost-effective; (4) has a {+-}1 C thermal profile compared to a {+-}10 C thermal profile for conventional gas furnaces; and (5) has a 25% to 50% smaller footprint.

  13. Standing wave compressor

    DOE Patents [OSTI]

    Lucas, Timothy S. (4614 River Mill Ct., Glen Allen, VA 23060)

    1991-01-01T23:59:59.000Z

    A compressor for compression-evaporation cooling systems, which requires no moving parts. A gaseous refrigerant inside a chamber is acoustically compressed and conveyed by means of a standing acoustic wave which is set up in the gaseous refrigerant. This standing acoustic wave can be driven either by a transducer, or by direct exposure of the gas to microwave and infrared sources, including solar energy. Input and output ports arranged along the chamber provide for the intake and discharge of the gaseous refrigerant. These ports can be provided with optional valve arrangements, so as to increase the compressor's pressure differential. The performance of the compressor in either of its transducer or electromagnetically driven configurations, can be optimized by a controlling circuit. This controlling circuit holds the wavelength of the standing acoustical wave constant, by changing the driving frequency in response to varying operating conditions.

  14. Piezoelectric wave motor

    DOE Patents [OSTI]

    Yerganian, Simon Scott (Lee's Summit, MO)

    2003-02-11T23:59:59.000Z

    A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase-shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in the direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

  15. Piezoelectric wave motor

    DOE Patents [OSTI]

    Yerganian, Simon Scott (Lee's Summit, MO)

    2001-07-17T23:59:59.000Z

    A piezoelectric motor having a stator in which piezoelectric elements are contained in slots formed in the stator transverse to the desired wave motion. When an electric field is imposed on the elements, deformation of the elements imposes a force perpendicular to the sides of the slot, deforming the stator. Appropriate frequency and phase shifting of the electric field will produce a wave in the stator and motion in a rotor. In a preferred aspect, the piezoelectric elements are configured so that deformation of the elements in direction of an imposed electric field, generally referred to as the d.sub.33 direction, is utilized to produce wave motion in the stator. In a further aspect, the elements are compressed into the slots so as to minimize tensile stresses on the elements in use.

  16. Overstability of acoustic waves in strongly magnetized anisotropic magnetohydrodynamic shear flows

    SciTech Connect (OSTI)

    Uchava, E. S. [Abastumani Astrophysical Observatory, Ilia State University, Tbilisi, Georgia (United States); Nodia Institute of Geophysics, Javakhishvili Tbilisi State University, Tbilisi, Georgia (United States); Faculty of Exact and Natural Sciences, Javakhishvili Tbilisi State University, 3 Chavchavadze Ave., Tbilisi 0179, Georgia (United States); Shergelashvili, B. M. [Institut für Theoretische Physik IV: Weltraum- und Astrophysik, Ruhr-Universitat Bochum, 44780 Bochum (Germany); Abastumani Astrophysical Observatory, Ilia State University, Tbilisi, Georgia (United States); CODeS, KU Leuven Campus Kortrijk, E. Sabbelaan 53, 8500 Kortrijk (Belgium); Tevzadze, A. G. [Faculty of Exact and Natural Sciences, Javakhishvili Tbilisi State University, 3 Chavchavadze Ave., Tbilisi 0179, Georgia (United States); Poedts, S. [Centre for Mathematical Plasma Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, 3001 Leuven (Belgium); Leuven Mathematical Modeling and Computational Science Center (LMCC), KU Leuven, Celestijnenlaan 200B, 3001 Leuven (Belgium)

    2014-08-15T23:59:59.000Z

    We present a linear stability analysis of the perturbation modes in anisotropic magnetohydrodynamic (MHD) flows with velocity shear and strong magnetic field. Collisionless or weakly collisional plasma is described within the 16-momentum MHD fluid closure model that takes into account not only the effect of pressure anisotropy but also the effect of anisotropic heat fluxes. In this model, the low frequency acoustic wave is revealed into a standard acoustic mode and higher frequency fast thermo-acoustic and lower frequency slow thermo-acoustic waves. It is shown that thermo-acoustic waves become unstable and grow exponentially when the heat flux parameter exceeds some critical value. It seems that velocity shear makes thermo-acoustic waves overstable even at subcritical heat flux parameters. Thus, when the effect of heat fluxes is not profound acoustic waves will grow due to the velocity shear, while at supercritical heat fluxes the flow reveals compressible thermal instability. Anisotropic thermal instability should be also important in astrophysical environments, where it will limit the maximal value of magnetic field that a low density ionized anisotropic flow can sustain.

  17. Adaptive multiconfigurational wave functions

    SciTech Connect (OSTI)

    Evangelista, Francesco A., E-mail: francesco.evangelista@emory.edu [Department of Chemistry and Cherry L. Emerson Center for Scientific Computation, Emory University, Atlanta, Georgia 30322 (United States)

    2014-03-28T23:59:59.000Z

    A method is suggested to build simple multiconfigurational wave functions specified uniquely by an energy cutoff ?. These are constructed from a model space containing determinants with energy relative to that of the most stable determinant no greater than ?. The resulting ?-CI wave function is adaptive, being able to represent both single-reference and multireference electronic states. We also consider a more compact wave function parameterization (?+SD-CI), which is based on a small ?-CI reference and adds a selection of all the singly and doubly excited determinants generated from it. We report two heuristic algorithms to build ?-CI wave functions. The first is based on an approximate prescreening of the full configuration interaction space, while the second performs a breadth-first search coupled with pruning. The ?-CI and ?+SD-CI approaches are used to compute the dissociation curve of N{sub 2} and the potential energy curves for the first three singlet states of C{sub 2}. Special attention is paid to the issue of energy discontinuities caused by changes in the size of the ?-CI wave function along the potential energy curve. This problem is shown to be solvable by smoothing the matrix elements of the Hamiltonian. Our last example, involving the Cu{sub 2}O{sub 2}{sup 2+} core, illustrates an alternative use of the ?-CI method: as a tool to both estimate the multireference character of a wave function and to create a compact model space to be used in subsequent high-level multireference coupled cluster computations.

  18. Real-time Water Waves with Wave Particles

    E-Print Network [OSTI]

    Yuksel, Cem

    2010-10-12T23:59:59.000Z

    This dissertation describes the wave particles technique for simulating water surface waves and two way fluid-object interactions for real-time applications, such as video games. Water exists in various different forms in our environment...

  19. Propagation of seismic waves through liquefied soils

    E-Print Network [OSTI]

    Taiebat, Mahdi; Jeremic, Boris; Dafalias, Yannis; Kaynia, Amir; Cheng, Zhao

    2010-01-01T23:59:59.000Z

    the mechanisms of wave propagation and ARTICLE IN PRESS M.Numerical analysis Wave propagation Earthquake Liquefactionenergy during any wave propagation. This paper summarizes

  20. California Small Hydropower and Ocean Wave Energy

    E-Print Network [OSTI]

    California Small Hydropower and Ocean Wave Energy Resources IN SUPPORT OF THE 2005 INTEGRATED....................................................................................................................... 9 Ocean Wave Energy............................................................................................................. 20 Wave Energy Conversion Technology

  1. mm-Wave Phase Shifters and Switches

    E-Print Network [OSTI]

    Adabi Firouzjaei, Ehsan

    2010-01-01T23:59:59.000Z

    4.1.1 Slow wave transmissioncombiners . . . . . . . . . . . 5.3 mm-Wave implementationfailed to predict current mm-wave design trend [1] . . . . .

  2. Heat Waves, Global Warming, and Mitigation

    E-Print Network [OSTI]

    Carlson, Ann E.

    2008-01-01T23:59:59.000Z

    Heat Waves, Global Warming, and Mitigation Ann E. Carlson*2008]HEAT WAVES, GLOBAL WARMING, AND MITIGATION 175 stroke2001). 2008]HEAT WAVES, GLOBAL WARMING, AND MITIGATION 177

  3. Wave refraction and wave energy on Cayo Arenas

    E-Print Network [OSTI]

    Walsh, Donald Eugene

    1962-01-01T23:59:59.000Z

    WAVE REFRACTION AND WAVE ENERGY ON CAYO ARENAS A Thesis By Donald E. Welsh Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of MASTER OF SCIENCE... January 1962 Major Subject: Physical Oceanography WAVE REFRACTION AND WAVE ENERGY ON CAYO ARENAS A Thesis Donald E. Walsh Approved as to style and content by: Chairman of the Committee ead of Department ' / January 1962 ACKNOWLEDGMENTS...

  4. Testing cosmology with cosmic sound waves

    SciTech Connect (OSTI)

    Corasaniti, Pier Stefano [LUTH, Observatoire de Paris, CNRS UMR 8102, Universite Paris Diderot, 5 Place Jules Janssen, 92195 Meudon Cedex (France); Melchiorri, Alessandro [Dipartimento di Fisica e Sezione INFN, Universita degli Studi di Roma 'La Sapienza', Ple Aldo Moro 5, 00185, Rome (Italy); CERN, Theory Division, CH-1211 Geneva 23 (Switzerland)

    2008-05-15T23:59:59.000Z

    Wilkinson Microwave Anisotropy Probe (WMAP) observations have accurately determined the position of the first two peaks and dips in the cosmic microwave background (CMB) temperature power spectrum. These encode information on the ratio of the distance to the last scattering surface to the sound horizon at decoupling. However prerecombination processes can contaminate this distance information. In order to assess the amplitude of these effects, we use the WMAP data and evaluate the relative differences of the CMB peak and dip multipoles. We find that the position of the first peak is largely displaced with respect to the expected position of the sound horizon scale at decoupling. In contrast, the relative spacings of the higher extrema are statistically consistent with those expected from perfect harmonic oscillations. This provides evidence for a scale dependent phase shift of the CMB oscillations which is caused by gravitational driving forces affecting the propagation of sound waves before recombination. By accounting for these effects we have performed a Markov Chain Monte Carlo likelihood analysis of the location of WMAP extrema to constrain, in combination with recent BAO data, a constant dark energy equation of state parameter w. For a flat universe we find a strong 2{sigma} upper limit w<-1.10, and including the Hubble Space Telescope prior, we obtain w<-1.14, which is only marginally consistent with limits derived from the Supernova Legacy Survey sample. On the other hand, we infer larger limits for nonflat cosmologies. From the full CMB likelihood analysis, we also estimate the values of the shift parameter R and the multipole l{sub a} of the acoustic horizon at decoupling for several cosmologies, to test their dependence on model assumptions. Although the analysis of the full CMB spectra should always be preferred, using the position of the CMB peaks and dips provides a simple and consistent method for combining CMB constraints with other data sets.

  5. Deflagration Wave Profiles

    SciTech Connect (OSTI)

    Menikoff, Ralph [Los Alamos National Laboratory

    2012-04-03T23:59:59.000Z

    Shock initiation in a plastic-bonded explosives (PBX) is due to hot spots. Current reactive burn models are based, at least heuristically, on the ignition and growth concept. The ignition phase occurs when a small localized region of high temperature (or hot spot) burns on a fast time scale. This is followed by a growth phase in which a reactive front spreads out from the hot spot. Propagating reactive fronts are deflagration waves. A key question is the deflagration speed in a PBX compressed and heated by a shock wave that generated the hot spot. Here, the ODEs for a steady deflagration wave profile in a compressible fluid are derived, along with the needed thermodynamic quantities of realistic equations of state corresponding to the reactants and products of a PBX. The properties of the wave profile equations are analyzed and an algorithm is derived for computing the deflagration speed. As an illustrative example, the algorithm is applied to compute the deflagration speed in shock compressed PBX 9501 as a function of shock pressure. The calculated deflagration speed, even at the CJ pressure, is low compared to the detonation speed. The implication of this are briefly discussed.

  6. Water Waves and Integrability

    E-Print Network [OSTI]

    Rossen I. Ivanov

    2007-07-12T23:59:59.000Z

    The Euler's equations describe the motion of inviscid fluid. In the case of shallow water, when a perturbative asymtotic expansion of the Euler's equations is taken (to a certain order of smallness of the scale parameters), relations to certain integrable equations emerge. Some recent results concerning the use of integrable equation in modeling the motion of shallow water waves are reviewed in this contribution.

  7. Magnetohydrodynamic Shearing Waves

    E-Print Network [OSTI]

    Bryan M. Johnson

    2007-02-12T23:59:59.000Z

    I consider the nonaxisymmetric linear theory of a rotating, isothermal magnetohydrodynamic (MHD) shear flow. The analysis is performed in the shearing box, a local model of a thin disk, using a decomposition in terms of shearing waves, i.e., plane waves in a frame comoving with the shear. These waves do not have a definite frequency as in a normal mode decomposition, and numerical integration of a coupled set of amplitude equations is required to characterize their time dependence. Their generic time dependence, however, is oscillatory with slowly-varying frequency and amplitude, and one can construct accurate analytical solutions by applying the Wentzel-Kramers-Brillouin method to the full set of amplitude equations. The solutions have the following properties: 1) Their accuracy increases with wavenumber, so that most perturbations that fit within the disk are well-approximated as modes with time-dependent frequencies and amplitudes. 2) They can be broadly classed as incompressive and compressive perturbations, the former including the nonaxisymmetric extension of magnetorotationally unstable modes, and the latter being the extension of fast and slow modes to a differentially-rotating medium. 3) Wave action is conserved, implying that their energy varies with frequency. 4) Their shear stress is proportional to the slope of their frequency, so that they transport angular momentum outward (inward) when their frequency increases (decreases). The complete set of solutions constitutes a comprehensive linear test suite for numerical MHD algorithms that incorporate a background shear flow. I conclude with a brief discussion of possible astrophysical applications.

  8. CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland

    E-Print Network [OSTI]

    Haller, Merrick

    CHARACTERIZING DANGEROUS WAVES FOR OCEAN WAVE ENERGY CONVERTER SURVIVABILITY Justin Hovland ABSTRACT Ocean Wave Energy Converters (OWECs) operating on the water surface are subject to storms at station 139. Keywords: wave energy, survivability, breaking waves, joint distribution, OWEC INTRODUCTION

  9. Aligned vertical fractures, HTI reservoir symmetry, and Thomsen seismic anisotropy parameters for polar media

    E-Print Network [OSTI]

    Berryman, James G.

    2008-01-01T23:59:59.000Z

    waves in such fractured reservoirs (Hsu and Schoenberg,i.e. , for cracked/fractured reservoirs), the vertical phasemore closely. FRACTURED RESERVOIRS AND CRACK-INFLUENCE

  10. Gas Explosion Characterization, Wave Propagation

    E-Print Network [OSTI]

    s & Dt^boooo^j Risø-R-525 Gas Explosion Characterization, Wave Propagation (Small-Scale Experiments EXPLOSION CHARACTERIZATION, WAVE PROPAGATION (Small-Scale Experiments) G.C. Larsen Abstract. A number characteristics 14 3.5. Characteristics of the primary pressure wave 21 3.6. Pressure propagation over a hard

  11. 2, 70177025, 2014 Freaque wave

    E-Print Network [OSTI]

    NHESSD 2, 7017­7025, 2014 Freaque wave occurrences in 2013 P. C. Liu Title Page Abstract to the corresponding final paper in NHESS if available. Brief Communication: Freaque wave occurrences in 2013 P. C. Liu­7025, 2014 Freaque wave occurrences in 2013 P. C. Liu Title Page Abstract Introduction Conclusions References

  12. EVOLUTION OF L HYBRID WAVES

    E-Print Network [OSTI]

    Karney, Charles

    is an envelope solitary wave. These solitary waves are not solitons. The occurrence of the constant phase pulses-state propagation of one of the two lower hybrid rays in a homogeneous considering the balance between thermal break up into two types of solitary waves, constant phase pulses or envelope pulses. e examine

  13. Microstructural Design for Stress Wave Energy Management /

    E-Print Network [OSTI]

    Tehranian, Aref

    2013-01-01T23:59:59.000Z

    Nemat-Nasser, Stress-wave energy management through materialNasser, S. , 2010. Stress-wave energy management throughconstitute pressure wave energy and/or shear wave energy.

  14. Introduction Modeling of large ocean waves Propagation speed Coherent wavetrains Near-shore wave dynamics Conclusions Tsunamis and ocean waves

    E-Print Network [OSTI]

    Craig, Walter

    Introduction Modeling of large ocean waves Propagation speed Coherent wavetrains Near-shore wave waves #12;Introduction Modeling of large ocean waves Propagation speed Coherent wavetrains NearMaster University Tsunamis and ocean waves #12;Introduction Modeling of large ocean waves Propagation speed Coherent

  15. Spatial modulation of in-plane magnetic anisotropy in epitaxial Co(111) films grown on macrostep-bunched Si(111)

    SciTech Connect (OSTI)

    Davydenko, A. V., E-mail: avdavydenko@gmail.com; Kozlov, A. G.; Chebotkevich, L. A. [Laboratory of Thin Film Technologies, Far Eastern Federal University, Vladivostok 690950 (Russian Federation)

    2014-10-14T23:59:59.000Z

    We compared magnetic properties of epitaxial Co(111) films grown on microstep- and macrostep-bunched vicinal Si(111) substrates. A surface of the microstep-bunched Si(111) substrate represents regular array of step-bunches with height of 1.7 nm divided from each other by flat microterraces with a width of 34 nm. A surface of the macrostep-bunched Si(111) substrate is constituted by macrostep bunches with a height of 75–85 nm divided by atomically flat macroterraces. The average sum width of a macrostep bunch and a macroterrace is 2.3 ?m. While in-plane magnetic anisotropy was spatially uniform in Co(111) films grown on the microstep-bunched Si(111), periodic macromodulation of the topography of the Si(111) substrate induced spatial modulation of in-plane magnetic anisotropy in Co(111) film grown on the macrostep-bunched Si(111) surface. The energy of uniaxial magnetic anisotropy in the areas of the Co(111) film deposited on the Si(111) macrosteps was higher more than by the order of magnitude than the energy of the magnetic anisotropy in the areas grown on macroterraces. Magnetization reversal in the areas with different energy of the magnetic anisotropy occurred in different magnetic fields. We showed the possibility of obtaining high density of domain walls in Co(111) film grown on the macrostep-bunched Si(111) by tuning the spatial step density of the Si(111) substrate.

  16. On the Experimental Substantiation of Anisotropy of Inertial Mass of Body in the Earth Gravitation Field

    E-Print Network [OSTI]

    Alexander L. Dmitriev

    2009-03-25T23:59:59.000Z

    On the basis of the field concept of gravitation and gravitational analogue of the Faradays induction law the difference of inertial mass of a body at its accelerated movement in horizontal and vertical directions relative to the Earth is shown. For an illustration of such a distinction the results of comparison of a motion of balance mechanical watch at horizontal and vertical orientations of balance axis are given. The expediency of statement of precision mechanical experiments with measurement of anisotropy of the inertial mass is noted, allowing to estimate the validity of the field approach in the description of gravitation.

  17. Phase-Diagram of Ultrathin Ferromagnetic-Films with Perpendicular Anisotropy

    E-Print Network [OSTI]

    Abanov, Artem; KALATSKY, V.; Pokrovsky, Valery L.; SASLOW, WM.

    1995-01-01T23:59:59.000Z

    with compression ( B?u) and bending ( 8? u ). In addition, fourth-order gradient terms in the exchange en- ergy within the conventional domain walls yield a contin- uum stripe orientation anisotropy energy density that tends to stabilize the conventional domain... the conventional domain walls, the magnetostatic energy is given by ?1) "J I V(R ?)f(Bu, B'u?)dydy', m, n where A,dr= A, ?(NQ/a )cd, where cd is a dimensionless number on the order of unity for the N= 1 square lattice, and varying as lnlV for sufficiently...

  18. Momentum anisotropies in the quark coalescence model RID A-2398-2009

    E-Print Network [OSTI]

    Kolb, PF; Chen, LW; Greco, V.; Ko, Che Ming.

    2004-01-01T23:59:59.000Z

    . Lett. 90, 202303 (2003); C. Nonaka, R. J. Fries, and S. A. Bass, Phys. Lett. B 583, 73 (2004). [21] V. Greco, C. M. Ko, and P. Levai, Phys. Rev. C 68, 034904 (2003); Phys. Rev. Lett. 90, 202302 (2003). [22] R. C. Hwa and C. B. Yang, Phys. Rev. C 67...); Nucl. Phys. A698, 375c (2002); Z. W. Lin and C. M. Ko, Phys. Rev. C 65, 034904 (2002); Z. W. Lin, C. M. Ko, and S. Pal, Phys. Rev. Lett. 89, 152301 (2002). MOMENTUM ANISOTROPIES IN THE QUARK? PHYSICAL REVIEW C 69, 051901(R) (2004) RAPID...

  19. Current induced perpendicular-magnetic-anisotropy racetrack memory with magnetic field assistance

    SciTech Connect (OSTI)

    Zhang, Y.; Klein, J.-O.; Chappert, C.; Ravelosona, D. [IEF, University of Paris-Sud, Orsay 91405 (France); UMR8622, CNRS, Orsay 91405 (France); Zhao, W. S., E-mail: weisheng.zhao@u-psud.fr [IEF, University of Paris-Sud, Orsay 91405 (France); UMR8622, CNRS, Orsay 91405 (France); Electronics and Information Engineering School, University of Beihang, Beijing 100191 (China)

    2014-01-20T23:59:59.000Z

    High current density is indispensable to shift domain walls (DWs) in magnetic nanowires, which limits the using of racetrack memory (RM) for low power and high density purposes. In this paper, we present perpendicular-magnetic-anisotropy (PMA) Co/Ni RM with global magnetic field assistance, which lowers the current density for DW motion. By using a compact model of PMA RM and 40?nm design kit, we perform mixed simulation to validate the functionality of this structure and analyze its density potential. Stochastic DW motion behavior has been taken into account and statistical Monte-Carlo simulations are carried out to evaluate its reliability performance.

  20. Gap anisotropy and universal pairing scale in a spin-fluctuation model of cuprate superconductors

    E-Print Network [OSTI]

    Abanov, Artem; Chubukov, A. V.; Norman, M. R.

    2008-01-01T23:59:59.000Z

    Gap anisotropy and universal pairing scale in a spin-fluctuation model of cuprate superconductors Ar. Abanov,1 A. V. Chubukov,2 and M. R. Norman3 1Department of Physics, Texas A&M University, College Station, Texas 77843, USA 2Department...-Tc cu- prate superconductors is a key problem.1 Some argue that the pseudogap originates from #1;quasi-#2;long-range order in a non- pairing channel #1;two-gap scenario#2;.2 Others argue instead that the pseudogap is a phase in which fermions already...

  1. Unidirectional anisotropy in the spin pumping voltage in yttrium iron garnet/platinum bilayers

    SciTech Connect (OSTI)

    Vilela-Leao, L. H.; Salvador, C.; Azevedo, A.; Rezende, S. M.

    2011-09-05T23:59:59.000Z

    Detailed measurements of the dc voltage generated in a thin Pt layer deposited on films of yttrium iron garnet (YIG) have been carried out to study the spin pumping effect produced by magnetostatic (MS) modes excited by a microwave field. In relatively thick YIG films the modes are far apart so that one can identify clearly the spin pumping voltage in V{sub SP} produced by each MS mode. We have discovered that when the sputter deposition of the thin Pt layer is made on the YIG film magnetized by a static magnetic field, V{sub SP} exhibits a strong unidirectional anisotropy.

  2. Random anisotropy disorder in superfluid 3He-A in aerogel

    E-Print Network [OSTI]

    G. E. Volovik

    2006-10-04T23:59:59.000Z

    The anisotropic superfluid 3He-A in aerogel provides an interesting example of a system with continuous symmetry in the presence of random anisotropy disorder. Recent NMR experiments allow us to discuss two regimes of the orientational disorder, which have different NMR properties. One of them, the (s)-state, is identified as the pure Larkin-Imry-Ma state. The structure of another state, the (f)-state, is not very clear: probably it is the Larkin-Imry-Ma state contaminated by the network of the topological defects pinned by aerogel.

  3. Azimuthal Anisotropy of $?$ and $?^{0}$ Mesons in Heavy-Ion Collisions at 2 AGeV

    E-Print Network [OSTI]

    A. Taranenko; A. Kugler; R. Pleskac; P. Tlusty; V. Wagner; H. Lohner; R. W. Ostendorf; R. H. Siemssen; P. H. Vogt; H. W. Wilschut; R. Averbeck; S. Hlavac; R. Holzmann; A. Schubert; R. S. Simon; R. Stratmann; F. Wissmann; Y. Charbonnier; G. Martinez; Y. Schutz; J. Diaz; A. Marin; A. Doppenschmidt; M. Appenheimer; V. Hejny; V. Metag; R. Novotny; H. Stroher; J. Weiss; A. R. Wolf; M. Wolf; TAPS Collaboration

    1999-03-15T23:59:59.000Z

    Azimuthal distributions of $\\eta$ and $\\pi^{0}$ mesons emitted at midrapidity in collisions of 1.9 AGeV $^{58}$Ni+$^{58}$Ni and 2 AGeV $^{40}$Ca+$^{nat}$Ca are studied as a function of the number of projectile-like spectator nucleons. The observed anisotropy corresponds to a negative elliptic flow signal for $\\eta$ mesons, indicating a preferred emission perpendicular to the reaction plane. The effect is smallest in peripheral Ni+Ni collisions. In contrast, for $\\pi^{0}$ mesons, elliptic flow is observed only in peripheral Ni+Ni collisions, changing from positive to negative sign with increasing pion transverse momentum.

  4. Particle acceleration at shock waves moving at arbitrary speed: the case of large scale magnetic field and anisotropic scattering

    E-Print Network [OSTI]

    G. Morlino; P. Blasi; M. Vietri

    2007-01-08T23:59:59.000Z

    A mathematical approach to investigate particle acceleration at shock waves moving at arbitrary speed in a medium with arbitrary scattering properties was first discussed in (Vietri 2003) and (Blasi & Vietri 2005}. We use this method and somewhat extend it in order to include the effect of a large scale magnetic field in the upstream plasma, with arbitrary orientation with respect to the direction of motion of the shock. We also use this approach to investigate the effects of anisotropic scattering on spectra and anisotropies of the distribution function of the accelerated particles.

  5. PROPAGATION OF SEISMIC WAVES THROUGH A SPATIO-TEMPORALLY FLUCTUATING MEDIUM: HOMOGENIZATION

    SciTech Connect (OSTI)

    Hanasoge, Shravan M. [Department of Geosciences, Princeton University, Princeton, NJ 08544 (United States); Gizon, Laurent [Max-Planck-Institut fuer Sonnensystemforschung, D-37191 Katlenburg-Lindau (Germany); Bal, Guillaume [Department of Applied and Physical Mathematics, Columbia University, New York, NY 10027 (United States)

    2013-08-20T23:59:59.000Z

    Measurements of seismic wave travel times at the photosphere of the Sun have enabled inferences of its interior structure and dynamics. In interpreting these measurements, the simplifying assumption that waves propagate through a temporally stationary medium is almost universally invoked. However, the Sun is in a constant state of evolution, on a broad range of spatio-temporal scales. At the zero-wavelength limit, i.e., when the wavelength is much shorter than the scale over which the medium varies, the WKBJ (ray) approximation may be applied. Here, we address the other asymptotic end of the spectrum, the infinite-wavelength limit, using the technique of homogenization. We apply homogenization to scenarios where waves are propagating through rapidly varying media (spatially and temporally), and derive effective models for the media. One consequence is that a scalar sound speed becomes a tensorial wave speed in the effective model and anisotropies can be induced depending on the nature of the perturbation. The second term in this asymptotic two-scale expansion, the so-called corrector, contains contributions due to higher-order scattering, leading to the decoherence of the wave field. This decoherence may be causally linked to the observed wave attenuation in the Sun. Although the examples we consider here consist of periodic arrays of perturbations to the background, homogenization may be extended to ergodic and stationary random media. This method may have broad implications for the manner in which we interpret seismic measurements in the Sun and for modeling the effects of granulation on the scattering of waves and distortion of normal-mode eigenfunctions.

  6. Nonlinear Hysteretic Torsional Waves

    E-Print Network [OSTI]

    J. Cabaret; P. Béquin; G. Theocharis; V. Andreev; V. E. Gusev; V. Tournat

    2015-01-09T23:59:59.000Z

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control devices such as strong amplitude-dependent filters.

  7. Nonlinear Hysteretic Torsional Waves

    E-Print Network [OSTI]

    Cabaret, J; Theocharis, G; Andreev, V; Gusev, V E; Tournat, V

    2015-01-01T23:59:59.000Z

    We theoretically study and experimentally report the propagation of nonlinear hysteretic torsional pulses in a vertical granular chain made of cm-scale, self-hanged magnetic beads. As predicted by contact mechanics, the torsional coupling between two beads is found nonlinear hysteretic. This results in a nonlinear pulse distortion essentially different from the distortion predicted by classical nonlinearities, and in a complex dynamic response depending on the history of the wave particle angular velocity. Both are consistent with the predictions of purely hysteretic nonlinear elasticity and the Preisach-Mayergoyz hysteresis model, providing the opportunity to study the phenomenon of nonlinear dynamic hysteresis in the absence of other type of material nonlinearities. The proposed configuration reveals a plethora of interesting phenomena including giant amplitude-dependent attenuation, short term memory as well as dispersive properties. Thus, it could find interesting applications in nonlinear wave control de...

  8. Geophysical Prospecting 39, 337-355, 1991 EXTENSIVE-DILATANCY ANISOTROPY

    E-Print Network [OSTI]

    Edinburgh, University of

    in synthetic shear-waves in reflection gathers and VSPs, in order to assess the relative merits of the two, and the behaviour of shear-wave splitting is dominated by the structure of the rock mass in the vicinity and preferentially aligned pore-space, which pervade most rocks in the crust and are ' Received January 1990

  9. DNA waves and water

    E-Print Network [OSTI]

    L. Montagnier; J. Aissa; E. Del Giudice; C. Lavallee; A. Tedeschi; G. Vitiello

    2010-12-23T23:59:59.000Z

    Some bacterial and viral DNA sequences have been found to induce low frequency electromagnetic waves in high aqueous dilutions. This phenomenon appears to be triggered by the ambient electromagnetic background of very low frequency. We discuss this phenomenon in the framework of quantum field theory. A scheme able to account for the observations is proposed. The reported phenomenon could allow to develop highly sensitive detection systems for chronic bacterial and viral infections.

  10. Tunable exchange bias-like effect in patterned hard-soft two-dimensional lateral composites with perpendicular magnetic anisotropy

    SciTech Connect (OSTI)

    Hierro-Rodriguez, A., E-mail: ahierro@fc.up.pt; Alvarez-Prado, L. M.; Martín, J. I.; Alameda, J. M. [Departamento de Física, Universidad de Oviedo, C/Calvo Sotelo S/N, 33007 Oviedo (Spain); Centro de Investigación en Nanomateriales y Nanotecnología—CINN (CSIC—Universidad de Oviedo—Principado de Asturias), Parque Tecnológico de Asturias, 33428 Llanera (Spain); Teixeira, J. M. [IN-IFIMUP, Departamento de Física e Astronomia, Faculdade de Ciências, Universidade do Porto, Rua Campo Alegre 687, 4169-007 Porto (Portugal); Vélez, M. [Departamento de Física, Universidad de Oviedo, C/Calvo Sotelo S/N, 33007 Oviedo (Spain)

    2014-09-08T23:59:59.000Z

    Patterned hard-soft 2D magnetic lateral composites have been fabricated by e-beam lithography plus dry etching techniques on sputter-deposited NdCo{sub 5} thin films with perpendicular magnetic anisotropy. Their magnetic behavior is strongly thickness dependent due to the interplay between out-of-plane anisotropy and magnetostatic energy. Thus, the spatial modulation of thicknesses leads to an exchange coupled system with hard/soft magnetic regions in which rotatable anisotropy of the thicker elements provides an extra tool to design the global magnetic behavior of the patterned lateral composite. Kerr microscopy studies (domain imaging and magneto-optical Kerr effect magnetometry) reveal that the resulting hysteresis loops exhibit a tunable exchange bias-like shift that can be switched on/off by the applied magnetic field.

  11. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

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

    Abreu, P; Aglietta, M; Ahn, E J; Albuquerque, I F.M.; Allard, D; Allekotte, I; Allen, J; Allison, P; Alvarez Castillo, J; Alvarez-Muniz, J; et al

    2011-06-17T23:59:59.000Z

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrativemore »values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.« less

  12. Magnetic anisotropies in epitaxial Fe{sub 3}O{sub 4}/GaAs(100) patterned structures

    SciTech Connect (OSTI)

    Zhang, W., E-mail: xiaotur@gmail.com; Zhang, D.; Yuan, S. J.; Huang, Z. C.; Zhai, Y. [Department of Physics, Southeast University, Nanjing 211189 (China); Wong, P. K. J. [NanoElectronics Group, MESA Institute for Nanotechnology, University of Twente, P. O. Box 217, 7500 AE Enschede (Netherlands); Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 (Singapore); Wu, J. [Department of Physics, University of York, York YO10 5DD (United Kingdom); Xu, Y. B. [Spintronics and Nanodevice Laboratory, Department of Electronics, University of York, York, YO10 5DD (United Kingdom)

    2014-10-15T23:59:59.000Z

    Previous studies on epitaxial Fe{sub 3}O{sub 4} rings in the context of spin-transfer torque effect have revealed complicated and undesirable domain structures, attributed to the intrinsic fourfold magnetocrystalline anisotropy in the ferrite. In this Letter, we report a viable solution to this problem, utilizing a 6-nm-thick epitaxial Fe{sub 3}O{sub 4} thin film on GaAs(100), where the fourfold magnetocrystalline anisotropy is negligible. We demonstrate that in the Fe{sub 3}O{sub 4} planar wires patterned from our thin film, such a unique magnetic anisotropy system has been preserved, and relatively simple magnetic domain configurations compared to those previous reports can be obtained.

  13. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

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

    Abreu, P [Lisbon, IST; Aglietta, M [IFSI, Turin; Ahn, E J [Fermilab; Albuquerque, I F.M. [Sao Paulo U.; Allard, D [APC, Paris; Allekotte, I [Centro Atomico Bariloche; Allen, J [New York U.; Allison, P [Ohio State U.; Alvarez Castillo, J [Mexico U., ICN; Alvarez-Muniz, J [Santiago de Compostela U.; Ambrosio, M [Napoli Seconda U.; INFN, Naples; Nijmegen U., IMAPP

    2011-06-17T23:59:59.000Z

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

  14. Alternating magnetic anisotropy of Li 2 ( Li 1 - x T x ) N ( T = Mn , Fe , Co , and Ni )

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

    Jesche, A.; Ke, L.; Jacobs, J. L.; Harmon, B.; Houk, R. S.; Canfield, P. C.

    2015-05-01T23:59:59.000Z

    Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li?(Li1-xTx)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy plane?easy axis?easy plane?easy axis when progressing from T = Mn ? Fe ? Co ? Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model. The calculated magnetic anisotropies show surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.

  15. Alternating magnetic anisotropy of Li 2 ( Li 1 - x T x ) N ( T = Mn , Fe , Co , and Ni )

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

    Jesche, A.; Ke, L.; Jacobs, J. L.; Harmon, B.; Houk, R. S.; Canfield, P. C.

    2015-05-01T23:59:59.000Z

    Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li?(Li1-xTx)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy plane?easy axis?easy plane?easy axis when progressing from T = Mn ? Fe ? Co ? Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model.more »The calculated magnetic anisotropies show surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.« less

  16. MEASUREMENT OF THE ANISOTROPY OF COSMIC-RAY ARRIVAL DIRECTIONS WITH ICECUBE

    SciTech Connect (OSTI)

    Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M.; BenZvi, S. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Subatomic and Radiation Physics, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Auffenberg, J.; Becker, K.-H. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Bazo Alba, J. L.; Benabderrahmane, M. L. [DESY, D-15735 Zeuthen (Germany); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Science Faculty CP230, Universite Libre de Bruxelles, B-1050 Brussels (Belgium); Becker, J. K., E-mail: rasha.abbasi@icecube.wisc.ed, E-mail: paolo.desiati@icecube.wisc.ed [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

    2010-08-01T23:59:59.000Z

    We report the first observation of an anisotropy in the arrival direction of cosmic rays with energies in the multi-TeV region in the Southern sky using data from the IceCube detector. Between 2007 June and 2008 March, the partially deployed IceCube detector was operated in a configuration with 1320 digital optical sensors distributed over 22 strings at depths between 1450 and 2450 m inside the Antarctic ice. IceCube is a neutrino detector, but the data are dominated by a large background of cosmic-ray muons. Therefore, the background data are suitable for high-statistics studies of cosmic rays in the southern sky. The data include 4.3 billion muons produced by downward-going cosmic-ray interactions in the atmosphere; these events were reconstructed with a median angular resolution of 3{sup 0} and a median energy of {approx}20 TeV. Their arrival direction distribution exhibits an anisotropy in right ascension with a first-harmonic amplitude of (6.4 {+-} 0.2 stat. {+-} 0.8 syst.) x 10{sup -4}.

  17. Suppressing the impact of a high tensor-to-scalar ratio on the temperature anisotropies

    E-Print Network [OSTI]

    Carlo R. Contaldi; Marco Peloso; Lorenzo Sorbo

    2014-07-05T23:59:59.000Z

    The BICEP2 collaboration has reported a strong B mode signal in the CMB polarization, which is well fit by a tensor-to-scalar ratio of r ~ 0.2. This is greater than the upper limit r data. The most advocated explanation involves a variation of n_s with scales (denoted as running) that has a magnitude significantly greater than the generic slow roll predictions. We instead study the possibility that the large scale temperature anisotropies are not enhanced because of a suppression of the scalar power at large scales. Such a situation can be achieved for instance by a sudden change of the speed of the inflaton (by about 14 %), and we show that it fits the temperature anisotropies and polarization data considerably better than a constant running (its chi^2 improves by ~ 7.5 over that of the constant running, at the cost of one more parameter). We also consider the possibility that the large scale temperature fluctuations are suppressed by an anti-correlation between tensor and scalar modes. Unfortunately, while such effect does affect the temperature fluctuations at large scales, it does not affect the temperature power spectrum and cannot, therefore, help in reconciling a large value of r with the limits from temperature fluctuations.

  18. Temperature-dependent elastic anisotropy and mesoscale deformation in a nanostructured ferritic alloy

    SciTech Connect (OSTI)

    Stoica, Grigoreta M [ORNL; Stoica, Alexandru Dan [ORNL; Miller, Michael K [ORNL; Ma, Dong [ORNL

    2014-01-01T23:59:59.000Z

    Nanostructured ferritic alloys (NFA) are a new class of ultrafine-grained oxide dispersion-strengthened steels, promising for service in extreme environments of high temperature and high irradiation in the next-generation of nuclear reactors. This is owing to the remarkable stability of their complex microstructures containing a high density of Y-Ti-O nanoclusters within grains and along the grain boundaries. While nanoclusters have been recognized to be the primary contributor to the exceptional resistance to irradiation and high-temperature creep, very little is known about the mechanical roles of the polycrystalline grains that constitute the bulk ferritic matrix. Here we report the mesoscale characterization of anisotropic responses of the ultrafine NFA grains to tensile stresses at various temperatures using the state-of-the-art in situ neutron diffraction. We show the first experimental determination of temperature-dependent single-crystal elastic constants for the NFA, and reveal a strong temperature-dependent elastic anisotropy due to a sharp decrease in the shear stiffness constant [c'=(c_11-c_12)/2] when a critical temperature ( T_c ) is approached, indicative of elastic softening and instability of the ferritic matrix. We also show, from anisotropy-induced intergranular strain/stress accumulations, that a common dislocation slip mechanism operates at the onset of yielding for low temperatures, while there is a deformation crossover from low-temperature lattice hardening to high temperature lattice softening in response to extensive plastic deformation.

  19. Acceleration and Enrichment of 3He in Impulsive Solar Flares by Electron Firehose Waves

    E-Print Network [OSTI]

    G. Paesold; R. Kallenbach; A. O. Benz

    2002-09-08T23:59:59.000Z

    A new mechanism for acceleration and enrichment of 3He during impulsive solar flares is presented. Low-frequency electromagnetic plasma waves excited by the Electron Firehose Instability (EFI) can account for the acceleration of ions up to 1 MeV/amu energies as a single stage process. The EFI arises as a direct consequence of the free energy stored in a temperature anisotropy (T_parallel>T_perp) of the bulk energized electron population during the acceleration process. In contrast to other mechanisms which require special plasma properties, the EFI is an intrinsic feature of the acceleration process of the bulk electrons. Being present as a side effect in the flaring plasma, these waves can account for the acceleration of 3He and 4He while selectively enhancing 3He due to the spectral energy density built up from linear growth. Linearized kinetic theory, analytic models and test-particle simulations have been applied to investigate the ability of the waves to accelerate and fractionate. As waves grow in both directions parallel to the magnetic field, they can trap resonant ions and efficiently accelerate them to the highest energies. Plausible models have been found that can explain the observed energies, spectra and abundances of 3He and 4He.

  20. Deformation fabrics of olivine in Val Malenco peridotite found in Italy and implications for the seismic anisotropy in the upper mantle

    E-Print Network [OSTI]

    Jung, Haemyeong

    for the interpretation of seismic data. Seismic polarization anisotropy in the upper mantle has been observed in many, seismic data (i.e., seismic anisotropy) have been interpreted on the basis of the type-A LPO of olivine al., 2004; Katayama and Karato, 2006); this has led to a new era for the interpretation of seismic

  1. Nondestructive testing using stress waves: wave propagation in layered media

    E-Print Network [OSTI]

    Ortega, Jose Alberto

    2013-02-22T23:59:59.000Z

    NONDESTRUCTIVE TESTING USING STRESS WAVES: WAVE PROPAGATION IN LAYERED MEDIA A Senior Honors Thesis by JOSE ALBERTO ORTEGA Submitted to the Office of Honors Program & Academic Scholarships Texas A&M University in partial fulfillment... of the requirement of the UNIVERSITY UNDERGRADUATE RESEARCH FELLOWS April 2002 Group: Engineering NONDESTRUCTIVE TESTING USI WAVE PROPAGATION IN LA A Senior Honors The ~pe -C JOSE ALBERTO ORTI /CI Submitted to the Office of Honors Program k. Academic...

  2. Mechanism of tailored magnetic anisotropy in amorphous Co{sub 68}Fe{sub 24}Zr{sub 8} thin films

    SciTech Connect (OSTI)

    Fu, Yu, E-mail: yu.fu@uni-due.de, E-mail: cangcangzhulin@gmail.com; Meckenstock, R.; Farle, M. [Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, 47057 Duisburg (Germany); Barsukov, I., E-mail: ibarsuko@uci.edu [Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, 47057 Duisburg (Germany); Physics and Astronomy, University of California, Irvine, California 92697 (United States); Lindner, J. [Fakultät für Physik and Center for Nanointegration Duisburg-Essen (CeNIDE), Universität Duisburg-Essen, 47057 Duisburg (Germany); Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf e.V., Bautzner Landstr. 400, 01328 Dresden (Germany); Raanaei, H. [Department of Physics, Persian Gulf University, Bushehr 75169 (Iran, Islamic Republic of); Hjörvarsson, B. [Department of Physics and Astronomy, Uppsala University, Box 516 SE-75120 Uppsala (Sweden)

    2014-02-17T23:59:59.000Z

    The mechanism of tailored magnetic anisotropy in amorphous Co{sub 68}Fe{sub 24}Zr{sub 8} thin films was investigated by ferromagnetic resonance (FMR) on samples deposited without an applied magnetic field, with an out-of-plane field and an in-plane field. Analysis of FMR spectra profiles, high frequency susceptibility calculations, and statistical simulations using a distribution of local uniaxial magnetic anisotropy reveal the presence of atomic configurations with local uniaxial anisotropy, of which the direction can be tailored while the magnitude remains at an intrinsically constant value of 3.0(2) kJ/m{sup 3}. The in-plane growth field remarkably sharpens the anisotropy distribution and increases the sample homogeneity. The results benefit designing multilayer spintronic devices based on highly homogeneous amorphous layers with tailored magnetic anisotropy.

  3. Elements of Radio Waves

    E-Print Network [OSTI]

    Frank G. Borg; Ismo Hakala; Jukka Määttälä

    2007-12-24T23:59:59.000Z

    We present a summary of the basic properties of the radio wave generation, propagation and reception, with a special attention to the gigahertz bandwidth region which is of interest for wireless sensor networks. We also present some measurement results which use the so-called RSSI indicator in order to track how the field strength varies with position and distance of the transceivers. We hope the paper may be useful to anyone who looks for a quick review of the fundamentals of electromagnetic theory with application to antennas.

  4. Spin waves in the (

    SciTech Connect (OSTI)

    Lipscombe, O. J. [University of Tennessee, Knoxville (UTK); Chen, G. F. [The Institute of Physics, Chinese Academy of Sciences; Fang, Chen [Purdue University; Perring, T. G. [ISIS Facility, Rutherford Appleton Laboratory; Abernathy, Douglas L [ORNL; Christianson, Andrew D [ORNL; Egami, Takeshi [ORNL; Wang, Nanlin [The Institute of Physics, Chinese Academy of Sciences; Hu, Jiangping [Purdue University and Chinese Academy of Sciences; Dai, Pengcheng [University of Tennessee, Knoxville (UTK)

    2011-01-01T23:59:59.000Z

    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.

  5. Wave-driven

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOETHE FUTURE LOOKSof Energy Wave

  6. Wave Decay in MHD Turbulence

    E-Print Network [OSTI]

    Andrey Beresnyak; Alex Lazarian

    2008-05-06T23:59:59.000Z

    We present a model for nonlinear decay of the weak wave in three-dimensional incompressible magnetohydrodynamic (MHD) turbulence. We show that the decay rate is different for parallel and perpendicular waves. We provide a general formula for arbitrarily directed waves and discuss particular limiting cases known in the literature. We test our predictions with direct numerical simulations of wave decay in three-dimensional MHD turbulence, and discuss the influence of turbulent damping on the development of linear instabilities in the interstellar medium and on other important astrophysical processes.

  7. Interface boundary conditions for dynamic magnetization and spin wave dynamics in a ferromagnetic layer with the interface Dzyaloshinskii-Moriya interaction

    SciTech Connect (OSTI)

    Kostylev, M. [School of Physics, M013, University of Western Australia, Crawley, Perth 6009, Western Australia (Australia)

    2014-06-21T23:59:59.000Z

    In this work, we derive the interface exchange boundary conditions for the classical linear dynamics of magnetization in ferromagnetic layers with the interface Dzyaloshinskii-Moriya interaction (IDMI). We show that IDMI leads to pinning of dynamic magnetization at the interface. An unusual peculiarity of the IDMI-based pinning is that its scales as the spin-wave wave number. We incorporate these boundary conditions into an existing numerical model for the dynamics of the Damon-Eshbach spin wave in ferromagnetic films. IDMI affects the dispersion and the frequency non-reciprocity of the travelling Damon-Eshbach spin wave. For a broad range of film thicknesses L and wave numbers, the results of the numerical simulations of the spin wave dispersion are in a good agreement with a simple analytical expression, which shows that the contribution of IDMI to the dispersion scales as 1/L, similarly to the effect of other types of interfacial anisotropy. Suggestions to experimentalists how to detect the presence of IDMI in a spin wave experiment are given.

  8. 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

    2004-12-02T23:59:59.000Z

    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.

  9. Seismic velocity and Q anisotropy in fractured poroelastic media Juan E. Santos a,b,c,n

    E-Print Network [OSTI]

    Santos, Juan

    , knowledge of fracture orientation, densities and sizes is essential since these factors control hydrocarbon (fractal) skeleton with fractures. We show that fractures induce strong seismic velocity and Q anisotropy subject in hydrocarbon exploration geophysics, mining and reser- voir characterization and production [1

  10. OBSERVATION OF ANISOTROPY IN THE GALACTIC COSMIC-RAY ARRIVAL DIRECTIONS AT 400 TeV WITH ICECUBE

    SciTech Connect (OSTI)

    Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Ackermann, M.; Bazo Alba, J. L. [DESY, D-15735 Zeuthen (Germany); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Allen, M. M. [Department of Physics, Pennsylvania State University, University Park, PA 16802 (United States); Altmann, D. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Auffenberg, J. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Science Faculty CP230, Universite Libre de Bruxelles, B-1050 Brussels (Belgium); Becker, J. K. [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Collaboration: IceCube Collaboration; and others

    2012-02-10T23:59:59.000Z

    In this paper we report the first observation in the Southern hemisphere of an energy dependence in the Galactic cosmic-ray anisotropy up to a few hundred TeV. This measurement was performed using cosmic-ray-induced muons recorded by the partially deployed IceCube observatory between 2009 May and 2010 May. The data include a total of 33 Multiplication-Sign 10{sup 9} muon events with a median angular resolution of {approx}3 Degree-Sign . A sky map of the relative intensity in arrival direction over the Southern celestial sky is presented for cosmic-ray median energies of 20 and 400 TeV. The same large-scale anisotropy observed at median energies around 20 TeV is not present at 400 TeV. Instead, the high-energy sky map shows a different anisotropy structure including a deficit with a post-trial significance of -6.3{sigma}. This anisotropy reveals a new feature of the Galactic cosmic-ray distribution, which must be incorporated into theories of the origin and propagation of cosmic rays.

  11. Friction anisotropy at Ni,,100...,,100... interfaces: Molecular dynamics studies Yue Qi and Yang-Tse Cheng

    E-Print Network [OSTI]

    Goddard III, William A.

    Friction anisotropy at Ni,,100...Õ,,100... interfaces: Molecular dynamics studies Yue Qi and Yang of Technology, Pasadena, California, 91125 Received 8 March 2002; published 30 August 2002 The friction theories predict that most perfect clean incommensurate interfaces would produce no static friction

  12. Experimental and computational analysis of toughness anisotropy in an AA2139 Al-alloy for aerospace applications

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    1 Experimental and computational analysis of toughness anisotropy in an AA2139 Al-alloy for aerospace applications T.F. Morgeneyer1,3 , J. Besson1 , H. Proudhon1 , M.J. Starink2 and I. Sinclair2 1

  13. Anisotropy of Imbalanced Alfvenic Turbulence in Fast Solar Wind R. T. Wicks,1,* T. S. Horbury,1

    E-Print Network [OSTI]

    California at Berkeley, University of

    energy to yet smaller scales [3­5]. In the fast wind, the turbulence is imbalanced: there is more power solar wind [8] and from numerical simulations [9] that balanced tur- bulence is made up of locallyAnisotropy of Imbalanced Alfve´nic Turbulence in Fast Solar Wind R. T. Wicks,1,* T. S. Horbury,1 C

  14. Magnetic domain pinning in an anisotropy-engineered GdTbFe thin film Stan Konings,a

    E-Print Network [OSTI]

    fields, these do- mains collapse to bubble domains which are found to local- ize on the irradiated dots lattices of 50 nm sized dots. The effect of the anisotropy patterns, differing in ion fluence and interdot of the irregularly shaped domains is observed. In perpendicular magnetic fields, however, the high field bubble

  15. A non-volatile-memory device on the basis of engineered anisotropies in (Ga,Mn)As

    E-Print Network [OSTI]

    Loss, Daniel

    ARTICLES A non-volatile-memory device on the basis of engineered anisotropies in (Ga,Mn)As KATRIN by Moore's law, the semiconductor industry will need to develop novel device concepts that go beyond simple Hall effect6 , tunnelling AMR (TAMR)7­9 and Coulomb blockade AMR10 . These previous demonstrations have

  16. Oxygen-assisted room-temperature deposition of CoPt3 films with perpendicular magnetic anisotropy

    E-Print Network [OSTI]

    Hellman, Frances

    Oxygen-assisted room-temperature deposition of CoPt3 films with perpendicular magnetic anisotropy B Jolla, California 92093 Received 23 July 2002; accepted 30 September 2002 Trace amounts of oxygen CoPt3 grown by vapor deposition at or slightly above room temperature. Oxygen is known to act

  17. Wave Evolution On the Evolution of Curvelets

    E-Print Network [OSTI]

    Smith, Hart F.

    Curvelets Wave Evolution On the Evolution of Curvelets by the Wave Equation Hart F. Smith of Curvelets by the Wave Equation #12;Curvelets Wave Evolution Curvelets and the Second Dyadic Decomposition Curvelets A curvelet frame {} is a wave packet frame on L2(R2) based on second dyadic decomposition. f

  18. Wave Mechanics and the Fifth Dimension

    E-Print Network [OSTI]

    Paul S. Wesson; James M. Overduin

    2013-01-28T23:59:59.000Z

    Replacing 4D Minkowski space by 5D canonical space leads to a clearer derivation of the main features of wave mechanics, including the wave function and the velocity of de Broglie waves. Recent tests of wave-particle duality could be adapted to investigate whether de Broglie waves are basically 4D or 5D in nature.

  19. Shear wave transducer for boreholes

    DOE Patents [OSTI]

    Mao, N.H.

    1984-08-23T23:59:59.000Z

    A technique and apparatus is provided for estimating in situ stresses by measuring stress-induced velocity anisotropy around a borehole. Two sets each of radially and tangentially polarized transducers are placed inside the hole with displacement directions either parallel or perpendicular to the principal stress directions. With this configuration, relative travel times are measured by both a pulsed phase-locked loop technique and a cross correlation of digitized waveforms. The biaxial velocity data are used to back-calculate the applied stress.

  20. Observation of Optical Solitons and Abnormal Modulation Instability in Liquid Crystals with Negative Dielectric Anisotropy

    E-Print Network [OSTI]

    Wang, Jing; Chen, Junzhu; Liu, Jinlong; Wang, Zhuo; Li, Yiheng; Guo, Qi; Hu, Wei; Xuan, Li

    2015-01-01T23:59:59.000Z

    We investigate theoretically and experimentally the optical beam propagation in the nematic liquid crystal with negative dielectric anisotropy, which is aligned homeotropically in a $80\\mu m$-thickness planar cell in the presence of an externally voltage. It is predicted that the nonlocal nonlinearity of liquid crystal undergo an oscillatory response function with a negative nonlinear refractive index coefficient. We found that the oscillatory nonlocal nonlinearity can support stable bright solitons, which are observed in experiment. We also found that abnormal modulation instability occurs with infinity gain coefficient at a fixed spatial frequency, which is no depend on the beam intensity. We observed the modulation instability in the liquid crystal at a very low intensity ($0.26W/cm^2$), and the maximum gain frequency were found kept unchange when beam power changes over 2-3 orders of magnitude.

  1. A Possible Anisotropy in Blackbody Radiation Viewed through Non-uniform Gaseous Matter

    E-Print Network [OSTI]

    Ray-Dastidar, T K

    1999-01-01T23:59:59.000Z

    A non-local gauge symmetry of a complex scalar field, which can be trivially extended to spinor fields, was demonstrated in a recent paper (Mod.Phys.Lett. A13, 1265 (1998) ; hep-th/9902020). The corresponding covariant Lagrangian density yielded a new, non-local Quantum Electrodynamics. In the present paper it is shown that as a consequence of this new QED, a blackbody radiation viewed through gaseous matter appears to show a slight deviation from the Planck formula, and we propose an experimental test to check this effect. We also show that a non-uniformity in this gaseous matter distribution leads to an (apparent) spatial anisotropy in the blackbody radiation.

  2. Dome-like variation of the superconducting gap anisotropy in Fe-based superconductors

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

    Prozorov, Ruslan; Cho, Kyuil; Kim, Hyong June; Tanatar, Makariy

    2013-07-17T23:59:59.000Z

    Experiments performed on different iron-based superconductors suggest a variety of possible structures of the superconducting energy gap, both nodeless and nodal. To understand the pairing mechanisms, it is important to identify common features in the behavior of different materials. Measurements of the temperature - dependent London penetration depth provide important information on the structure of the superconducting gap. We show that despite significant differences between different iron - based superconductors, there is a universal trend: the gap is least anisotropic at the optimal doping and its anisotropy increases upon the departure towards underdoped and overdoped ends of the ''superconducting dome''.more »This trend is not related to the presence of the long-range magnetic order in the underdoped state.« less

  3. Influence of magnetic electrodes thicknesses on the transport properties of magnetic tunnel junctions with perpendicular anisotropy

    SciTech Connect (OSTI)

    Cuchet, Léa; Rodmacq, Bernard; Auffret, Stéphane; Sousa, Ricardo C.; Dieny, Bernard [SPINTEC, UMR 8191, CEA-INAC/CNRS/UJF-Grenoble 1/Grenoble-INP, 38054 Grenoble Cedex (France)

    2014-08-04T23:59:59.000Z

    The influence of the bottom and top magnetic electrodes thicknesses on both perpendicular anisotropy and transport properties is studied in (Co/Pt)/Ta/CoFeB/MgO/FeCoB/Ta magnetic tunnel junctions. By carefully investigating the relative magnetic moment of the two electrodes as a function of their thicknesses, we identify and quantify the presence of magnetically dead layers, likely localized at the interfaces with Ta, that is, 0.33?nm for the bottom electrode and 0.60?nm for the top one. Critical thicknesses (spin-reorientation transitions) are determined as 1.60 and 1.65?nm for bottom and top electrodes, respectively. The tunnel magnetoresistance ratio reaches its maximum value, as soon as both effective (corrected from dead layer) electrode thicknesses exceed 0.6?nm.

  4. Time delay anisotropy in photoelectron emission from the isotropic ground state of helium

    E-Print Network [OSTI]

    Heuser, Sebastian; Cirelli, Claudio; Sabbar, Mazyar; Boge, Robert; Lucchini, Matteo; Gallmann, Lukas; Ivanov, Igor; Kheifets, Anatoli S; Dahlström, J Marcus; Lindroth, Eva; Argenti, Luca; Martín, Fernando; Keller, Ursula

    2015-01-01T23:59:59.000Z

    Time delays of electrons emitted from an isotropic initial state and leaving behind an isotropic ion are assumed to be angle-independent. Using an interferometric method involving XUV attosecond pulse trains and an IR probe field in combination with a detection scheme, which allows for full 3D momentum resolution, we show that time delays between electrons liberated from the $1s^{2}$ spherically symmetric ground state of He depend on the emission direction of the electrons with respect to the linear polarization axis of the ionizing XUV light. Such time delays can exhibit values as large as 60 attoseconds. With the help of refined theoretical models we can attribute the observed anisotropy to the interplay between different final quantum states, which arise naturally when two photons are involved in the photoionization process. Since most measurement techniques tracing attosecond electron dynamics have involved at least two photons so far, this is a general, significant, and initially unexpected effect that m...

  5. Origin of shape anisotropy effects in solution-phase synthesized FePt nanomagnets

    SciTech Connect (OSTI)

    Ferrer, D. A.; Guchhait, S.; Liu, H.; Ferdousi, F.; Corbet, C.; Xu, H.; Saha, S.; Ramon, M.; Banerjee, S. K. [Microelectronics Research Center, University of Texas at Austin, Austin, Texas 78758 (United States); Doczy, M.; Bourianoff, G. [Intel Corporation, Hillsboro, Oregon, 97124 (United States); Mathew, L.; Rao, R. [Astrowatt Inc, Austin, Texas, 78758 (United States); Ganguly, S. [Electrical Engineering Department, Indian Institute of Technology, Bombay 400076 (India); Markert, J. T. [Department of Physics, University of Texas at Austin, Austin, Texas 78712 (United States)

    2011-07-01T23:59:59.000Z

    Controlling the morphology of inorganic nanocrystals is important because many of their electronic attributes are highly sensitive to shape and aspect ratio. FePt nanocrystals have potential as advanced magnetic materials for ultrahigh-density memory. This is due to their high shape and/or magnetocrystalline anisotropy, which allows bits as small as 3 nm to be thermally stable over typical data storage periods of 10 years. Herein, nanocrystals were simply fabricated by simultaneous reduction of platinum acetylacetonate and thermal decomposition of iron pentacarbonyl in properly chosen conditions of solvent/surfactant proportions and temperature for rational design of their shape and magnetic properties. This work has combined magnetometry measurements and micromagnetic simulations to illustrate the role of the external shape on the rotation of the magnetization vector for colloidal assemblies.

  6. Electron theory of perpendicular magnetic anisotropy of Co-ferrite thin films

    SciTech Connect (OSTI)

    Inoue, Jun-ichiro; Yanagihara, Hideto; Kita, Eiji [Institute of Applied Physics, University of Tsukuba, Tsukuba 305-8573 (Japan)] [Institute of Applied Physics, University of Tsukuba, Tsukuba 305-8573 (Japan); Niizeki, Tomohiko [Institute of Applied Physics, University of Tsukuba, Tsukuba 305-8573 (Japan) [Institute of Applied Physics, University of Tsukuba, Tsukuba 305-8573 (Japan); AIMR, Tohoku University, Sendai 980-8577 (Japan); Itoh, Hiroyoshi [Department of Pure and Applied Physics, Kansai University, Suita 564-8680 (Japan)] [Department of Pure and Applied Physics, Kansai University, Suita 564-8680 (Japan)

    2014-02-15T23:59:59.000Z

    We develop an electron theory for the t{sub 2g} electrons of Co{sup 2+} ions to clarify the perpendicular magnetic anisotropy (PMA) mechanism of Co-ferrite thin films by considering the spin-orbit interaction (SOI) and crystal-field (CF) potentials induced by the local symmetry around the Co ions and the global tetragonal symmetry of the film. Uniaxial and in-plane MA constants K{sub u} and K{sub 1} at 0 K, respectively, are calculated for various values of SOI and CF. We show that reasonable parameter values explain the observed PMA and that the orbital moment for the in-plane magnetization reduces to nearly half of that of the out-of-plane magnetization.

  7. Anisotropy studies around the Galactic Centre at EeV energies with the Auger Observatory

    SciTech Connect (OSTI)

    Aglietta, M.; Aguirre, C.; Allard, D.; Allekotte, I.; Allison, P.; Alvarez, C.; Alvarez-Muniz, J.; Ambrosio, M.; Anchordoqui, L.; Anjos, J.C.; Aramo, C.; /Centro Atomico Bariloche /Buenos Aires, IAFE /Buenos Aires, CONICET /Pierre Auger Observ. /La Plata U. /Natl. Tech. U., San Rafael /Adelaide U. /Catholic U. of Bolivia, La Paz /Bolivia U. /Rio de Janeiro, CBPF /Sao Paulo U.; ,

    2006-07-01T23:59:59.000Z

    Data from the Pierre Auger Observatory are analyzed to search for anisotropies near the direction of the Galactic Centre at EeV energies. The exposure of the surface array in this part of the sky is already significantly larger than that of the fore-runner experiments. Our results do not support previous findings of localized excesses in the AGASA and SUGAR data. We set an upper bound on a point-like flux of cosmic rays arriving from the Galactic Centre which excludes several scenarios predicting sources of EeV neutrons from Sagittarius A. Also the events detected simultaneously by the surface and fluorescence detectors (the ''hybrid'' data set), which have better pointing accuracy but are less numerous than those of the surface array alone, do not show any significant localized excess from this direction.

  8. Dome-like variation of the superconducting gap anisotropy in Fe-based superconductors

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

    Prozorov, Ruslan [Ames Lab., Ames, IA (United States); Cho, Kyuil [Ames Lab., Ames, IA (United States); Kim, Hyong June [Ames Lab., Ames, IA (United States); Tanatar, Makariy [Ames Lab., Ames, IA (United States)

    2013-07-17T23:59:59.000Z

    Experiments performed on different iron-based superconductors suggest a variety of possible structures of the superconducting energy gap, both nodeless and nodal. To understand the pairing mechanisms, it is important to identify common features in the behavior of different materials. Measurements of the temperature - dependent London penetration depth provide important information on the structure of the superconducting gap. We show that despite significant differences between different iron - based superconductors, there is a universal trend: the gap is least anisotropic at the optimal doping and its anisotropy increases upon the departure towards underdoped and overdoped ends of the ''superconducting dome''. This trend is not related to the presence of the long-range magnetic order in the underdoped state.

  9. Temporal and Spatial Turbulent Spectra of MHD Plasma and an Observation of Variance Anisotropy

    E-Print Network [OSTI]

    Schaffner, D A; Lukin, V S

    2014-01-01T23:59:59.000Z

    The nature of MHD turbulence is analyzed through both temporal and spatial magnetic fluctuation spectra. A magnetically turbulent plasma is produced in the MHD wind-tunnel configuration of the Swarthmore Spheromak Experiment (SSX). The power of magnetic fluctuations is projected into directions perpendicular and parallel to a local mean field; the ratio of these quantities shows the presence of variance anisotropy which varies as a function of frequency. Comparison amongst magnetic, velocity, and density spectra are also made, demonstrating that the energy of the turbulence observed is primarily seeded by magnetic fields created during plasma production. Direct spatial spectra are constructed using multi-channel diagnostics and are used to compare to frequency spectra converted to spatial scales using the Taylor Hypothesis. Evidence for the observation of dissipation due to ion inertial length scale physics is also discussed as well as the role laboratory experiment can play in understanding turbulence typica...

  10. Nanoparticle Shape Anisotropy Dictates the Collective Behavior of Surface-Bound Ligands

    SciTech Connect (OSTI)

    Jones, Matthew R.; Macfarlane, Robert J.; Prigodich, Andrew E.; Patel, Pinal C.; Mirkin, Chad A. (NWU)

    2012-11-14T23:59:59.000Z

    We report on the modification of the properties of surface-confined ligands in nanoparticle systems through the introduction of shape anisotropy. Specifically, triangular gold nanoprisms, densely functionalized with oligonucleotide ligands, hybridize to complementary particles with an affinity that is several million times higher than that of spherical nanoparticle conjugates functionalized with the same amount of DNA. In addition, they exhibit association rates that are 2 orders of magnitude greater than those of their spherical counterparts. This phenomenon stems from the ability of the flat, extended facets of nonspherical nanoparticles to (1) support more numerous ligand interactions through greater surface contact with complementary particles, (2) increase the effective local concentration of terminal DNA nucleotides that mediate hybridization, and (3) relieve the conformational stresses imposed on nanoparticle-bound ligands participating in interactions between curved surfaces. Finally, these same trends are observed for the pH-mediated association of nanoparticles functionalized with carboxylate ligands, demonstrating the generality of these findings.

  11. Dissipation of parallel and oblique Alfv\\'en-cyclotron waves: implications for minor ion heating in the solar wind

    E-Print Network [OSTI]

    Maneva, Y G; Moya, Pablo S; Wicks, R; Poedts, S

    2015-01-01T23:59:59.000Z

    We perform 2.5D hybrid simulations with massless fluid electrons and kinetic particle-in-cell ions to study the temporal evolution of ion temperatures, temperature anisotropies and velocity distribution functions in relation to the dissipation and turbulent evolution of a broad-band spectrum of parallel and obliquely propagating Alfv\\'en-cyclotron waves. The purpose of this paper is to study the relative role of parallel versus oblique Alfv\\'en-cyclotron waves in the observed heating and acceleration of minor ions in the fast solar wind. We consider collisionless homogeneous multi-species plasma, consisting of isothermal electrons, isotropic protons and a minor component of drifting $\\alpha$ particles in a finite-$\\beta$ fast stream near the Earth. The kinetic ions are modeled by initially isotropic Maxwellian velocity distribution functions, which develop non-thermal features and temperature anisotropies when a broad-band spectrum of low-frequency non-resonant, $\\omega \\leq 0.34 \\Omega_p$, Alfv\\'en-cyclotron...

  12. POWER ANISOTROPY IN THE MAGNETIC FIELD POWER SPECTRAL TENSOR OF SOLAR WIND TURBULENCE

    SciTech Connect (OSTI)

    Wicks, R. T.; Horbury, T. S. [Physics Department, Imperial College London, London SW7 2AZ (United Kingdom); Forman, M. A. [Department of Physics and Astronomy, Stony Brook University, Stony Brook, NY 11790-3800 (United States); Oughton, S., E-mail: r.wicks@imperial.ac.uk [Department of Mathematics, University of Waikato, Hamilton (New Zealand)

    2012-02-10T23:59:59.000Z

    We observe the anisotropy of the power spectral tensor of magnetic field fluctuations in the fast solar wind for the first time. In heliocentric RTN coordinates, the power in each element of the tensor has a unique dependence on the angle between the magnetic field and velocity of the solar wind ({theta}{sub B}) and the angle of the vector in the plane perpendicular to the velocity ({phi}{sub B}). We derive the geometrical effect of the high speed flow of the solar wind past the spacecraft on the power spectrum in the frame of the plasma P(k) to arrive at the observed power spectrum P(f, {theta}{sub B}, {phi}{sub B}) based on a scalar field description of turbulence theory. This allows us to predict the variation in the {phi}{sub B} direction and compare it to the data. We then transform the observations from RTN coordinates to magnetic-field-aligned coordinates. The observed reduced power spectral tensor matches the theoretical predictions we derive in both RTN and field-aligned coordinates, which means that the local magnetic field we calculate with wavelet envelope functions is an accurate representation of the physical axis of symmetry for the turbulence and implies that on average the turbulence is axisymmetric. We also show that we can separate the dominant toroidal component of the turbulence from the smaller but significant poloidal component and that these have different power anisotropy. We also conclude that the magnetic helicity is anisotropic and mostly two dimensional, arising from wavevectors largely confined to the plane perpendicular to B .

  13. Creating Wave-Focusing Materials

    E-Print Network [OSTI]

    A. G. Ramm

    2008-05-16T23:59:59.000Z

    Basic ideas for creating wave-focusing materials by injecting small particles in a given material are described. The number of small particles to be injected around any point is calculated. Inverse scattering problem with fixed wavenumber and fixed incident direction of the plane acoustic wave is formulated and solved.

  14. Colliding axisymmetric pp-waves

    E-Print Network [OSTI]

    B. V. Ivanov

    1997-10-21T23:59:59.000Z

    An exact solution is found describing the collision of axisymmetric pp-waves with M=0. They are impulsive in character and their coordinate singularities become point curvature singularities at the boundaries of the interaction region. The solution is conformally flat. Concrete examples are given, involving an ultrarelativistic black hole against a burst of pure radiation or two colliding beam- like waves.

  15. Fully nonlinear wave-current interactions and kinematics by a BEM-based numerical wave tank

    E-Print Network [OSTI]

    Lynett, Patrick

    Fully nonlinear wave-current interactions and kinematics by a BEM-based numerical wave tank S. Ryu and the resulting kinematics. In the present paper, the variation of wave amplitude and wave length and minimize wave reflections from the down- stream wall. Nonlinear wave kinematics as a result of nonlinear

  16. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A. (Lafayette, CA); Bakulin, Andrey (Houston, TX)

    2009-10-13T23:59:59.000Z

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  17. Tube-wave seismic imaging

    DOE Patents [OSTI]

    Korneev, Valeri A [LaFayette, CA

    2009-05-05T23:59:59.000Z

    The detailed analysis of cross well seismic data for a gas reservoir in Texas revealed two newly detected seismic wave effects, recorded approximately 2000 feet above the reservoir. A tube-wave (150) is initiated in a source well (110) by a source (111), travels in the source well (110), is coupled to a geological feature (140), propagates (151) through the geological feature (140), is coupled back to a tube-wave (152) at a receiver well (120), and is and received by receiver(s) (121) in either the same (110) or a different receiving well (120). The tube-wave has been shown to be extremely sensitive to changes in reservoir characteristics. Tube-waves appear to couple most effectively to reservoirs where the well casing is perforated, allowing direct fluid contact from the interior of a well case to the reservoir.

  18. Parallel electric field generation by Alfven wave turbulence

    E-Print Network [OSTI]

    Bian, N H; Brown, J C

    2010-01-01T23:59:59.000Z

    {This work aims to investigate the spectral structure of the parallel electric field generated by strong anisotropic and balanced Alfvenic turbulence in relation with the problem of electron acceleration from the thermal population in solar flare plasma conditions.} {We consider anisotropic Alfvenic fluctuations in the presence of a strong background magnetic field. Exploiting this anisotropy, a set of reduced equations governing non-linear, two-fluid plasma dynamics is derived. The low-$\\beta$ limit of this model is used to follow the turbulent cascade of the energy resulting from the non-linear interaction between kinetic Alfven waves, from the large magnetohydrodynamics (MHD) scales with $k_{\\perp}\\rho_{s}\\ll 1$ down to the small "kinetic" scales with $k_{\\perp}\\rho_{s} \\gg 1$, $\\rho_{s}$ being the ion sound gyroradius.} {Scaling relations are obtained for the magnitude of the turbulent electromagnetic fluctuations, as a function of $k_{\\perp}$ and $k_{\\parallel}$, showing that the electric field develops ...

  19. POLARIZATION AND COMPRESSIBILITY OF OBLIQUE KINETIC ALFVEN WAVES

    SciTech Connect (OSTI)

    Hunana, P.; Goldstein, M. L. [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)] [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States); Passot, T.; Sulem, P. L.; Laveder, D. [Laboratoire J. L. Lagrange, Universite de Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, BP 4229, F-06304 Nice Cedex 4 (France)] [Laboratoire J. L. Lagrange, Universite de Nice Sophia Antipolis, CNRS, Observatoire de la Cote d'Azur, BP 4229, F-06304 Nice Cedex 4 (France); Zank, G. P. [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35805 (United States)] [Center for Space Plasma and Aeronomic Research (CSPAR), University of Alabama in Huntsville, Huntsville, AL 35805 (United States)

    2013-04-01T23:59:59.000Z

    It is well known that a complete description of the solar wind requires a kinetic description and that, particularly at sub-proton scales, kinetic effects cannot be ignored. It is nevertheless usually assumed that at scales significantly larger than the proton gyroscale r{sub L} , magnetohydrodynamics or its extensions, such as Hall-MHD and two-fluid models with isotropic pressures, provide a satisfactory description of the solar wind. Here we calculate the polarization and magnetic compressibility of oblique kinetic Alfven waves and show that, compared with linear kinetic theory, the isotropic two-fluid description is very compressible, with the largest discrepancy occurring at scales larger than the proton gyroscale. In contrast, introducing anisotropic pressure fluctuations with the usual double-adiabatic (or CGL) equations of state yields compressibility values which are unrealistically low. We also show that both of these classes of fluid models incorrectly describe the electric field polarization. To incorporate linear kinetic effects, we use two versions of the Landau fluid model that include linear Landau damping and finite Larmor radius (FLR) corrections. We show that Landau damping is crucial for correct modeling of magnetic compressibility, and that the anisotropy of pressure fluctuations should not be introduced without taking into account the Landau damping through appropriate heat flux equations. We also show that FLR corrections to all the retained fluid moments appear to be necessary to yield the correct polarization. We conclude that kinetic effects cannot be ignored even for kr{sub L} << 1.

  20. 2011 Interference -1 INTERFERENCE OF SOUND WAVES

    E-Print Network [OSTI]

    Glashausser, Charles

    2011 Interference - 1 INTERFERENCE OF SOUND WAVES The objectives of this experiment are: · To measure the wavelength, frequency, and propagation speed of ultrasonic sound waves. · To observe interference phenomena with ultrasonic sound waves. APPARATUS: Oscilloscope, function generator, ultrasonic

  1. Electrostatic-plasma-wave energy flux

    E-Print Network [OSTI]

    Amendt, P.; Rostoker, N.

    1984-01-01T23:59:59.000Z

    would reduce cross- field wave-energy convection since theor cross-field leakage of wave energy are ap- that thecomposition of electrostatic-wave-energy field degrees of

  2. Walking Wave as a Model of Particle

    E-Print Network [OSTI]

    A. V. Goryunov

    2012-05-02T23:59:59.000Z

    The concept of walking wave is introduced from classical relativistic positions. One- and three-dimensional walking waves considered with their wave equations and dispersion equations. It is shown that wave characteristics (de Broglie's and Compton's wavelengths) and corpuscular characteristics (energy-momentum vector and the rest mass) of particle may be expressed through parameters of walking wave. By that the new view on a number concepts of physic related with wave-particle duality is suggested.

  3. Strain relaxation and enhanced perpendicular magnetic anisotropy in BiFeO{sub 3}:CoFe{sub 2}O{sub 4} vertically aligned nanocomposite thin films

    SciTech Connect (OSTI)

    Zhang, Wenrui; Jiao, Liang; Li, Leigang [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Jian, Jie; Khatkhatay, Fauzia; Chu, Frank [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843 (United States); Chen, Aiping [Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843 (United States); Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Jia, Quanxi [Center for Integrated Nanotechnologies (CINT), Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); MacManus-Driscoll, Judith L. [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom); Wang, Haiyan, E-mail: wangh@ece.tamu.edu [Department of Materials Science and Engineering, Texas A and M University, College Station, Texas 77843 (United States); Department of Electrical and Computer Engineering, Texas A and M University, College Station, Texas 77843 (United States)

    2014-02-10T23:59:59.000Z

    Self-assembled BiFeO{sub 3}:CoFe{sub 2}O{sub 4} (BFO:CFO) vertically aligned nanocomposite thin films have been fabricated on SrTiO{sub 3} (001) substrates using pulsed laser deposition. The strain relaxation mechanism between BFO and CFO with a large lattice mismatch has been studied by X-ray diffraction and transmission electron microscopy. The as-prepared nanocomposite films exhibit enhanced perpendicular magnetic anisotropy as the BFO composition increases. Different anisotropy sources have been investigated, suggesting that spin-flop coupling between antiferromagnetic BFO and ferrimagnetic CFO plays a dominant role in enhancing the uniaxial magnetic anisotropy.

  4. A holographic model of d-wave superconductor vortices with Lifshitz scaling

    E-Print Network [OSTI]

    Hong Guo; Fu-Wen Shu; Jing-He Chen; Hui Li; Ze Yu

    2015-02-03T23:59:59.000Z

    We study analytically the $d$-wave holographic superconductors with Lifshitz scaling in the presence of external magnetic field. The vortex lattice solutions of the model have also been obtained with different Lifshitz scaling. Our results imply that holographic $d$-wave superconductor is indeed a type II one even for different Lifshitz scaling. This is the same as the conventional $d$-wave superconductors in the Ginzburg-Landau theory. Our results also indicate that the dynamical exponent $z$ has no effect to the shape of the vortex lattice even after higher order corrections (away from the phase transition point $B_c$) are included. However, it has effects on the upper critical magnetic field $B_{c_2}$ through the fact that a larger $z$ results in a smaller $B_{c_2}$ and therefore influences the size (characterized by $r_0\\equiv 1/\\sqrt{B_{c_2}}$) of the vortex lattices. Furthermore, close comparisons between our results and those of the Ginzburg-Landau theory reveal the fact that the upper critical magnetic field $B_{c_2}$ is inversely proportional to the square of the superconducting coherence length $\\xi$, regardless of the anisotropy between space and time.

  5. Sandia National Laboratories: Wave Energy Resource Characterization...

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

    eECEnergyComputational Modeling & SimulationWave Energy Resource Characterization at US Test Sites Wave Energy Resource Characterization at US Test Sites Sandia Report Presents...

  6. Wave runup on cylinders subject to deep water random waves

    E-Print Network [OSTI]

    Indrebo, Ann Kristin

    2001-01-01T23:59:59.000Z

    The accurate prediction of wave runup on deepwater offshore platform columns is of great importance for design engineers. Although linear predictive models are commonly used in the design and analysis process, many of the important effects...

  7. Wave Energy Resource Analysis for Use in Wave Energy Conversion

    E-Print Network [OSTI]

    Pastor, J.; Liu, Y.; Dou, Y.

    2014-01-01T23:59:59.000Z

    the naturally available and technically recoverable resource in a given location. The methodology was developed by the EPRI and uses a modified Gamma spectrum that interoperates hindcast sea state parameter data produced by NOAA's Wave watch III. This Gamma...

  8. Backreacting p-wave Superconductors

    E-Print Network [OSTI]

    Raúl E. Arias; Ignacio Salazar Landea

    2013-01-28T23:59:59.000Z

    We study the gravitational backreaction of the non-abelian gauge field on the gravity dual to a 2+1 p-wave superconductor. We observe that as in the $p+ip$ system a second order phase transition exists between a superconducting and a normal state. Moreover, we conclude that, below the phase transition temperature $T_c$ the lowest free energy is achieved by the p-wave solution. In order to probe the solution, we compute the holographic entanglement entropy. For both $p$ and $p+ip$ systems the entanglement entropy satisfies an area law. For any given entangling surface, the p-wave superconductor has lower entanglement entropy.

  9. Nonlinear dust acoustic waves and shocks

    SciTech Connect (OSTI)

    Merlino, R. L.; Heinrich, J. R.; Hyun, S.-H.; Meyer, J. K. [Department of Physics and Astronomy, University of Iowa, Iowa City, Iowa 52242 (United States)

    2012-05-15T23:59:59.000Z

    We describe experiments on (1) nonlinear dust acoustic waves and (2) dust acoustic shocks performed in a direct current (DC) glow discharge dusty plasma. First, we describe experiments showing nonlinear dust acoustic waves characterized by waveforms of the dust density that are typically sharper in the wave crests and flatter in the wave troughs (compared to sinusoidal waves), indicating the development of wave harmonics. We discuss this behavior in terms of a second-order fluid theory for dust acoustic waves. Second, experimental observations of the propagation and steepening of large-amplitude dust acoustic waves into dust acoustic shock waves are presented. The observed shock wave evolution is compared with numerical calculations based on the Riemann solution of the fully nonlinear fluid equations for dust acoustic waves.

  10. Plasma waves driven by gravitational waves in an expanding universe

    E-Print Network [OSTI]

    D. B. Papadopoulos

    2002-05-22T23:59:59.000Z

    In a Friedmann-Robertson-Walker (FRW) cosmological model with zero spatial curvature, we consider the interaction of the gravitational waves with the plasma in the presence of a weak magnetic field. Using the relativistic hydromagnetic equations it is verified that large amplitude magnetosonic waves are excited, assuming that both, the gravitational field and the weak magnetic field do not break the homogeneity and isotropy of the considered FRW spacetime.

  11. The parametric decay of Alfven waves into shear Alfven waves and dust lower hybrid waves

    SciTech Connect (OSTI)

    Jamil, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Crescent Model School Shadman, Lahore 54000 (Pakistan); Shah, H. A.; Zubia, K.; Zeba, I.; Uzma, Ch. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salimullah, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)

    2010-07-15T23:59:59.000Z

    The parametric decay instability of Alfven wave into low-frequency electrostatic dust-lower-hybrid and electromagnetic shear Alfven waves has been investigated in detail in a dusty plasma in the presence of external/ambient uniform magnetic field. Magnetohydrodynamic fluid equations of plasmas have been employed to find the linear and nonlinear response of the plasma particles for this three-wave nonlinear coupling in a dusty magnetoplasma. Here, relatively high frequency electromagnetic Alfven wave has been taken as the pump wave. It couples with other two low-frequency internal possible modes of the dusty magnetoplasma, viz., the dust-lower-hybrid and shear Alfven waves. The nonlinear dispersion relation of the dust-lower-hybrid wave has been solved to obtain the growth rate of the parametric decay instability. The growth rate is maximum for small value of external magnetic field B{sub s}. It is noticed that the growth rate is proportional to the unperturbed electron number density n{sub oe}.

  12. Identified particle production, azimuthal anisotropy, and interferometry measurements in Au plus Au collisions at root s(NN)=9.2 GeV 

    E-Print Network [OSTI]

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baumgart, S.; Beavis, D. R.; Bellwied, R.; Benedosso, F.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bnzarov, I.; Bonner, B. E.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bridgeman, A.; Bruna, E.; Bueltmann, S.; Burton, T. P.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Catu, O.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K. E.; Christie, W.; Chung, P.; Clarke, R. F.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; de Souza, R. Derradi; Didenko, L.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Efimov, L. G.; Elhalhuli, E.; Elnimr, M.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, Carl A.; Gangadharan, D. R.; Ganti, M. S.; Garcia-Solis, E. J.; Geromitsos, A.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y. N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S. M.; Gupta, A.; Gupta, N.; Guryn, W.; Haag, B.; Hallman, T. J.; Hamed, A.; Han, L. -X; Harris, J. W.; Hays-Wehle, J. P.; Heinz, M.; Heppelmann, S.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jena, C.; Jin, F.; Jones, C. L.; Jones, P. G.; Joseph, J.; Judd, E. G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitan, J.; Kauder, K.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Kopytine, M.; Koralt, I.; Korsch, W.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Krus, M.; Kumar, L.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C-H; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, N.; Li, Y.; Li, Z.; Lin, G.; Lin, X.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Love, W. A.; Lu, Y.; Ludlam, T.; Ma, G. L.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Matulenko, Yu A.; McDonald, D.; McShane, T. S.; Meschanin, A.; Milner, R.; Minaev, N. G.; Mioduszewski, Saskia; Mischke, A.; Mitrovski, M. K.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Netrakanti, P. K.; Ng, M. J.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okada, H.; Okorokov, V.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Pile, P.; Planinic, M.; Ploskon, M. A.; Pluta, J.; Plyku, D.; Poljak, N.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Pujahari, P. R.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Rehberg, J. M.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Sahoo, R.; Sakai, S.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S. S.; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Staszak, D.; Stephans, G. S. F.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Symons, T. J. M.; de Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Tram, V. N.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A., Jr.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Videbaek, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.; Walker, M.; Wang, F.

    2010-01-01T23:59:59.000Z

    We present the first measurements of identified hadron production, azimuthal anisotropy, and pion interferometry from Au + Au collisions below the nominal injection energy at the BNL Relativistic Heavy-Ion Collider (RHIC) facility. The data were...

  13. Interface-roughening phase diagram of the three-dimensional Ising model for all interaction anisotropies from hard-spin mean-field theory

    E-Print Network [OSTI]

    Caglar, Tolga

    The roughening phase diagram of the d=3 Ising model with uniaxially anisotropic interactions is calculated for the entire range of anisotropy, from decoupled planes to the isotropic model to the solid-on-solid model, using ...

  14. Measurement of higher-order harmonic azimuthal anisotropy in PbPb collisions at ?s[subscript NN] = 2.76 TeV

    E-Print Network [OSTI]

    Apyan, Aram

    Measurements are presented by the CMS Collaboration at the Large Hadron Collider (LHC) of the higher-order harmonic coefficients that describe the azimuthal anisotropy of charged particles emitted in ?s[subscript NN] = ...

  15. Photoluminescence polarization anisotropy for studying long-range structural ordering within semiconductor multi-atomic alloys and organic crystals

    SciTech Connect (OSTI)

    Prutskij, T.; Percino, J. [Instituto de Ciencias, BUAP, Privada 17 Norte, No 3417, col. San Miguel Huyeotlipan, 72050, Puebla, Pue. (Mexico); Orlova, T. [Department of Chemical and Biochemical Engineering, University of Notre Dame, Notre Dame, IN (United States); Vavilova, L. [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya, St Petersburg 194021, Russian Federation (Russian Federation)

    2013-12-04T23:59:59.000Z

    Long-range structural ordering within multi-component semiconductor alloys and organic crystals leads to significant optical anisotropy and, in particular, to anisotropy of the photoluminescence (PL) emission. The PL emission of ternary and quaternary semiconductor alloys is polarized if there is some amount of the atomic ordering within the crystal structure. We analyze the polarization of the PL emission from the quaternary GaInAsP semiconductor alloy grown by Liquid Phase Epitaxy (LPE) and conclude that it could be caused by low degree atomic ordering within the crystal structure together with the thermal biaxial strain due to difference between the thermal expansion coefficients of the layer and the substrate. We also study the state of polarization of the PL from organic crystals in order to identify different features of the crystal PL spectrum.

  16. In-Plane Electronic Anisotropy of Underdoped ___122___ Fe-Arsenide Superconductors Revealed by Measurements of Detwinned Single Crystals

    SciTech Connect (OSTI)

    Fisher, Ian Randal

    2012-05-08T23:59:59.000Z

    The parent phases of the Fe-arsenide superconductors harbor an antiferromagnetic ground state. Significantly, the Neel transition is either preceded or accompanied by a structural transition that breaks the four fold symmetry of the high-temperature lattice. Borrowing language from the field of soft condensed matter physics, this broken discrete rotational symmetry is widely referred to as an Ising nematic phase transition. Understanding the origin of this effect is a key component of a complete theoretical description of the occurrence of superconductivity in this family of compounds, motivating both theoretical and experimental investigation of the nematic transition and the associated in-plane anisotropy. Here we review recent experimental progress in determining the intrinsic in-plane electronic anisotropy as revealed by resistivity, reflectivity and ARPES measurements of detwinned single crystals of underdoped Fe arsenide superconductors in the '122' family of compounds.

  17. Detection of electron energy distribution function anisotropy in a magnetized electron cyclotron resonance plasma by using a directional Langmuir probe

    SciTech Connect (OSTI)

    Shikama, T., E-mail: shikama@me.kyoto-u.ac.jp; Hasuo, M. [Department of Mechanical Engineering and Science, Graduate School of Engineering, Kyoto University, Kyoto 615-8540 (Japan); Kitaoka, H. [Faculty of Engineering, Undergraduate School of Engineering Science, Kyoto University, Kyoto 615-8540 (Japan)

    2014-07-15T23:59:59.000Z

    Anisotropy in the electron energy distribution function (EEDF) in an electron cyclotron resonance plasma with magnetized electrons and weakly magnetized ions is experimentally investigated using a directional Langmuir probe. Under an assumption of independent EEDFs in the directions parallel and perpendicular to the magnetic field, the directional variation of the EEDF is evaluated. In the measured EEDFs, a significantly large population density of electrons with energies larger than 30?eV is found in one of the cross-field directions depending on the magnetic field direction. With the aid of an electron trajectory calculation, it is suggested that the observed anisotropic electrons originate from the EEDF anisotropy and the cross-field electron drift.

  18. Wave Energy Extraction from buoys

    E-Print Network [OSTI]

    Garnaud, Xavier

    2009-01-01T23:59:59.000Z

    Different types of Wave Energy Converters currently tested or under development are using the vertical movement of floating bodies to generate electricity. For commercial applications, arrays have to be considered in order ...

  19. Jet quenching in shock waves

    E-Print Network [OSTI]

    Michael Spillane; Alexander Stoffers; Ismail Zahed

    2011-10-23T23:59:59.000Z

    We study the propagation of an ultrarelativistic light quark jet inside a shock wave using the holographic principle. The maximum stopping distance and its dependency on the energy of the jet is obtained.

  20. The unique dynamics of the Pacic Hemisphere mantle and its signature on seismic anisotropy

    E-Print Network [OSTI]

    Long, Bernard

    over su/ciently long length scales it can be detected by seismic waves, and consequently seismic-resolution seismic images of mantle structure. In the Pacific Hemisphere we find a dome-like upwelling, originating of the Pacific plate to the dome-like upwelling below the central Pacific Ocean and it also provides

  1. Estimation of interval anisotropy parameters using velocity-independent layer stripping

    E-Print Network [OSTI]

    Tsvankin, Ilya

    by VILS in the shale layer above the reservoir are more plausible and less influenced by noise than those Wang1 and Ilya Tsvankin1 ABSTRACT Moveout analysis of long-spread P-wave data is widely used it to interval parameter estimation in orthorhombic media using wide-azimuth, long- spread data

  2. Two-photon wave mechanics

    E-Print Network [OSTI]

    Brian J. Smith; M. G. Raymer

    2007-02-21T23:59:59.000Z

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

  3. Direct Drive Wave Energy Buoy

    SciTech Connect (OSTI)

    Rhinefrank, Kenneth E. [Columbia Power Technologies, Inc.; Lenee-Bluhm, Pukha [Columbia Power Technologies, Inc.; Prudell, Joseph H. [Columbia Power Technologies, Inc.; Schacher, Alphonse A. [Columbia Power Technologies, Inc.; Hammagren, Erik J. [Columbia Power Technologies, Inc.; Zhang, Zhe [Columbia Power Technologies, Inc.

    2013-07-29T23:59:59.000Z

    The most prudent path to a full-scale design, build and deployment of a wave energy conversion (WEC) system involves establishment of validated numerical models using physical experiments in a methodical scaling program. This Project provides essential additional rounds of wave tank testing at 1:33 scale and ocean/bay testing at a 1:7 scale, necessary to validate numerical modeling that is essential to a utility-scale WEC design and associated certification.

  4. Wave function as geometric entity

    E-Print Network [OSTI]

    B. I. Lev

    2011-02-10T23:59:59.000Z

    A new approach to the geometrization of the electron theory is proposed. The particle wave function is represented by a geometric entity, i.e., Clifford number, with the translation rules possessing the structure of Dirac equation for any manifold. A solution of this equation is obtained in terms of geometric treatment. Interference of electrons whose wave functions are represented by geometric entities is considered. New experiments concerning the geometric nature of electrons are proposed.

  5. A search for anisotropy in the arrival directions of ultra high energy cosmic rays recorded at the Pierre Auger Observatory

    SciTech Connect (OSTI)

    Abreu, P.; ,

    2012-01-01T23:59:59.000Z

    Observations of cosmic ray arrival directions made with the Pierre Auger Observatory have previously provided evidence of anisotropy at the 99% CL using the correlation of ultra high energy cosmic rays (UHECRs) with objects drawn from the Veron-Cetty Veron catalog. In this paper we report on the use of three catalog independent methods to search for anisotropy. The 2pt-L, 2pt+ and 3pt methods, each giving a different measure of self-clustering in arrival directions, were tested on mock cosmic ray data sets to study the impacts of sample size and magnetic smearing on their results, accounting for both angular and energy resolutions. If the sources of UHECRs follow the same large scale structure as ordinary galaxies in the local Universe and if UHECRs are deflected no more than a few degrees, a study of mock maps suggests that these three methods can efficiently respond to the resulting anisotropy with a P-value = 1.0% or smaller with data sets as few as 100 events. Using data taken from January 1, 2004 to July 31, 2010 we examined the 20, 30, ..., 110 highest energy events with a corresponding minimum energy threshold of about 51 EeV. The minimum P-values found were 13.5% using the 2pt-L method, 1.0% using the 2pt+ method and 1.1% using the 3pt method for the highest 100 energy events. In view of the multiple (correlated) scans performed on the data set, these catalog-independent methods do not yield strong evidence of anisotropy in the highest energy cosmic rays.

  6. Variations of decay rates of radio-active elements and their connections with global anisotropy of physical space

    E-Print Network [OSTI]

    Yu. A. Baurov; I. F. Malov

    2010-01-29T23:59:59.000Z

    The analysis of correlations between fluctuations of alpha- and beta-decay rates for different radio-active elements is carried out. These fluctuations exceed significantly errors of measurements in many cases. They have the periodical character and reveal definite spatial directions. We suggest that the observed fluctuations are caused by the unique physical reason connected with the global anisotropy of physical space and by the new force.

  7. Measurement of J/? Azimuthal Anisotropy in Au+Au Collisions at ?sNN=200 GeV

    SciTech Connect (OSTI)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Gliske, S.; Grebenyuk, O. G.; Grosnick, D.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jena, C.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kikola, D. P.; Kiryluk, J.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; deSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, W.; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yang, Y.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, X. P.; Zhang, Y.

    2013-08-01T23:59:59.000Z

    The measurement of J/? azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at ?sNN>/sub>=200 GeV. The measured J/? elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/? particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

  8. Measurement of J/? Azimuthal Anisotropy in Au+Au Collisions at ?sNN=200 GeV

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

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E.; Averichev, G. S.; Balewski, J.; Banerjee, A.; Barnovska, Z.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bruna, E.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Cai, X. Z.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chung, P.; Chwastowski, J.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Ding, F.; Dion, A.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Fersch, R. G.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Gliske, S.; Grebenyuk, O. G.; Grosnick, D.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hajkova, O.; Hamed, A.; Han, L-X.; Harris, J. W.; Hays-Wehle, J. P.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jena, C.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Kikola, D. P.; Kiryluk, J.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Korsch, W.; Kotchenda, L.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lima, L. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Lu, Y.; Luo, X.; Luszczak, A.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Mioduszewski, S.; Mitrovski, M. K.; Mohammed, Y.; Mohanty, B.; Mondal, M. M.; Munhoz, M. G.; Mustafa, M. K.; Naglis, M.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nogach, L. V.; Novak, J.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Oliveira, R. A. N.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Powell, C. B.; Pruneau, C.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Ruan, L.; Rusnak, J.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, B.; Schmitz, N.; Schuster, T. R.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shao, M.; Sharma, B.; Sharma, M.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; deSouza, U. G.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, W.; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yang, Y.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I-K.; Zawisza, M.; Zbroszczyk, H.; Zhang, J. B.; Zhang, S.; Zhang, X. P.; Zhang, Y.

    2013-08-01T23:59:59.000Z

    The measurement of J/? azimuthal anisotropy is presented as a function of transverse momentum for different centralities in Au+Au collisions at ?sNN>/sub>=200 GeV. The measured J/? elliptic flow is consistent with zero within errors for transverse momentum between 2 and 10 GeV/c. Our measurement suggests that J/? particles with relatively large transverse momenta are not dominantly produced by coalescence from thermalized charm quarks, when comparing to model calculations.

  9. Steady water waves with multiple critical layers

    E-Print Network [OSTI]

    Mats Ehrnström; Joachim Escher; Erik Wahlén

    2011-04-01T23:59:59.000Z

    We construct small-amplitude periodic water waves with multiple critical layers. In addition to waves with arbitrarily many critical layers and a single crest in each period, two-dimensional sets of waves with several crests and troughs in each period are found. The setting is that of steady two-dimensional finite-depth gravity water waves with vorticity.

  10. Anisotropy and chemical composition of ultra-high energy cosmic rays using arrival directions measured by the Pierre Auger Observatory

    SciTech Connect (OSTI)

    Abreu, P [Lisbon, IST; Aglietta, M [IFSI, Turin; Ahn, E J [Fermilab; Albuquerque, I F.M. [Sao Paulo U.; Allard, D [APC, Paris; Allekotte, I [Centro Atomico Bariloche; Allen, J [New York U.; Allison, P [Ohio State U.; Alvarez Castillo, J [Mexico U., ICN; Alvarez-Muniz, J [Santiago de Compostela U.; Ambrosio, M [Napoli Seconda U.; INFN, Naples; Nijmegen U., IMAPP

    2011-06-17T23:59:59.000Z

    The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E > Eth = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E > Eth are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above Eth/Z (for illustrative values of Z = 6,13,26). If the anisotropies above Eth are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

  11. The Anisotropic Line Correlation Function as a Probe of Anisotropies in Galaxy Surveys

    E-Print Network [OSTI]

    Eggemeier, Alexander; Smith, Robert E; Niemeyer, Jens

    2015-01-01T23:59:59.000Z

    We propose an anisotropic generalisation of the line correlation function (ALCF) to separate and quantify phase information in the large-scale structure of galaxies. The line correlation function probes the strictly non-linear regime of structure formation and since phase information drops out of the power spectrum, the line correlation function provides a complementary tool to commonly used techniques based on two-point statistics. Furthermore, it is independent of linear bias as well as the Gaussian variance on the modulus of the density field and thus may also prove to be advantageous compared to the bispectrum or similar higher-order statistics for certain cases. For future applications it is vital, though, to be able to account for observational effects that cause anisotropies in the distribution of galaxies. Based on a number of numerical studies, we find that our ALCF is well suited to accomplish this task and we demonstrate how the Alcock-Paczynski effect and kinematical redshift-space distortions can...

  12. Collective Diffusion of Colloidal Hard Rods in Smectic Liquid Crystals: Effect of Particle Anisotropy

    E-Print Network [OSTI]

    Alessandro Patti; Djamel El Masri; René van Roij; Marjolein Dijkstra

    2010-04-16T23:59:59.000Z

    We study the layer-to-layer diffusion in smectic-A liquid crystals of colloidal hard rods with different length-to-diameter ratios using computer simulations. The layered arrangement of the smectic phase yields a hopping-type diffusion due to the presence of permanent barriers and transient cages. Remarkably, we detect stringlike clusters composed of inter-layer rods moving cooperatively along the nematic director. Furthermore, we find that the structural relaxation in equilibrium smectic phases shows interesting similarities with that of out-of-equilibrium supercooled liquids, although there the particles are kinetically trapped in transient rather than permanent cages. Additionally, at fixed packing fraction we find that the barrier height increases with increasing particle anisotropy, and hence the dynamics is more heterogeneous and non-Gaussian for longer rods, yielding a lower diffusion coefficient along the nematic director and smaller clusters of inter-layer particles that move less cooperatively. At fixed barrier height, the dynamics becomes more non-Gaussian and heterogeneous for longer rods that move more collectively giving rise to a higher diffusion coefficient along the nematic director.

  13. On the dipole straylight contamination in spinning space missions dedicated to CMB anisotropy

    E-Print Network [OSTI]

    Carlo Burigana; Alessandro Gruppuso; Fabio Finelli

    2006-07-21T23:59:59.000Z

    We present an analysis of the dipole straylight contamination (DSC) for spinning space-missions designed to measure CMB anisotropies. Although this work is mainly devoted to the {\\sc Planck} project, it is relatively general and allows to focus on the most relevant DSC implications. We first study a simple analytical model for the DSC in which the pointing direction of the main spillover can be assumed parallel or not to the spacecraft spin axis direction and compute the time ordered data and map. The map is then analysed paying particular attention to the DSC of the low multipole coefficients of the map. Through dedicated numerical simulations we verify the analytical results and extend the analysis to higher multipoles and to more complex (and realistic) cases by relaxing some of the simple assumptions adopted in the analytical approach. We find that the systematic effect averages out in an even number of surveys, except for a contamination of the dipole itself that survives when spin axis and spillover directions are not parallel and for a contamination of the other multipoles in the case of complex scanning strategies. In particular, the observed quadrupole can be affected by the DSC in an odd number of surveys or in the presence of survey uncompleteness or over-completeness. Various aspects relevant in CMB space projects (such as implications for calibration, impact on polarization measurements, accuracy requirement in the far beam knowledge for data analysis applications, scanning strategy dependence) are discussed.

  14. The impact of dipole straylight contamination on the alignment of low multipoles of CMB anisotropies

    E-Print Network [OSTI]

    A. Gruppuso; C. Burigana; F. Finelli

    2007-01-10T23:59:59.000Z

    We estimate the impact of the Dipole Straylight Contamination (DSC) for the {\\it Planck} satellite on the alignments of vectors associated to the low multipoles of the pattern of the cosmic microwave background (CMB) anisotropies. In particular we study how the probability distributions of eighteen estimators for the alignments change when DSC is taken into account. We find that possible residual DSC should leave a non-negligible impact on low multipole alignments for effective values of the fractional far sidelobe integrated response, $p$, larger than $\\sim {\\rm few} \\times 10^{-3}$. The effect is strongly dependent on the intrinsic sky amplitude and weakly dependent on the considered scanning strategy. We find a decrease of the alignment probability between the quadrupole and the dipole and an increase of the alignment probability between the hexadecapole and the dipole (larger is the intrinsic sky amplitude and lower is the contamination). The remaining estimators do not exhibit clear signatures, except, in some cases, considering the largest values of $p$ and the lowest sky amplitudes. Provided that the real sidelobes of the {\\it Planck} receivers in flight conditions will correspond to $p \\lsim {\\rm few} \\times 10^{-3}$, as realistically expected at least in the cosmological frequency channels, and will be known with accuracies better than $\\sim {\\rm few} \\times 10$% allowing for a suitable cleaning during data reduction, {\\it Planck} will be very weakly affected from DSC on the alignments of low multipoles.

  15. Electronic structure and chemical bonding anisotropy investigation of wurtzite AlN

    E-Print Network [OSTI]

    Magnuson, M; Höglund, C; Birch, J; Hultman, L; 10.1103/PhysRevB.80.155105

    2011-01-01T23:59:59.000Z

    The electronic structure and the anisotropy of the Al - N {\\pi} and {\\sigma} chemical bonding of wurtzite AlN has been investigated by bulk-sensitive total fluorescence yield absorption and soft x-ray emission spectroscopies. The measured N K, Al L1, and Al L2,3 x-ray emission and N 1s x-ray absorption spectra are compared with calculated spectra using first principles density-functional theory including dipole transition matrix elements. The main N 2p - Al 3p hybridization regions are identified at -1.0 to -1.8 eV and -5.0 to -5.5 eV below the top of the valence band. In addition, N 2s - Al 3p and N 2s - Al 3s hybridization regions are found at the bottom of the valence band around -13.5 eV and -15 eV, respectively. A strongly modified spectral shape of Al 3s states in the Al L2,3 emission from AlN in comparison to Al metal is found, which is also reflected in the N 2p - Al 3p hybridization observed in the Al L1 emission. The differences between the electronic structure and chemical bonding of AlN and Al met...

  16. Azimuthal anisotropy in U+U and Au+Au collisions at RHIC

    E-Print Network [OSTI]

    STAR Collaboration; L. Adamczyk; J. K. Adkins; G. Agakishiev; M. M. Aggarwal; Z. Ahammed; I. Alekseev; J. Alford; A. Aparin; D. Arkhipkin; E. C. Aschenauer; G. S. Averichev; V. Bairathi; A. Banerjee; R. Bellwied; A. Bhasin; A. K. Bhati; P. Bhattarai; J. Bielcik; J. Bielcikova; L. C. Bland; I. G. Bordyuzhin; J. Bouchet; A. V. Brandin; I. Bunzarov; J. Butterworth; H. Caines; M. Calderón de la Barca Sánchez; J. M. Campbell; D. Cebra; M. C. Cervantes; I. Chakaberia; P. Chaloupka; Z. Chang; S. Chattopadhyay; J. H. Chen; X. Chen; J. Cheng; M. Cherney; W. Christie; G. Contin; H. J. Crawford; S. Das; L. C. De Silva; R. R. Debbe; T. G. Dedovich; J. Deng; A. A. Derevschikov; B. di Ruzza; L. Didenko; C. Dilks; X. Dong; J. L. Drachenberg; J. E. Draper; C. M. Du; L. E. Dunkelberger; J. C. Dunlop; L. G. Efimov; J. Engelage; G. Eppley; R. Esha; O. Evdokimov; O. Eyser; R. Fatemi; S. Fazio; P. Federic; J. Fedorisin; Z. Feng; P. Filip; Y. Fisyak; C. E. Flores; L. Fulek; C. A. Gagliardi; D. Garand; F. Geurts; A. Gibson; M. Girard; L. Greiner; D. Grosnick; D. S. Gunarathne; Y. Guo; A. Gupta; S. Gupta; W. Guryn; A. Hamad; A. Hamed; R. Haque; J. W. Harris; L. He; S. Heppelmann; S. Heppelmann; A. Hirsch; G. W. Hoffmann; D. J. Hofman; S. Horvat; B. Huang; H. Z. Huang; X. Huang; P. Huck; T. J. Humanic; G. Igo; W. W. Jacobs; H. Jang; K. Jiang; E. G. Judd; S. Kabana; D. Kalinkin; K. Kang; K. Kauder; H. W. Ke; D. Keane; A. Kechechyan; Z. H. Khan; D. P. Kikola; I. Kisel; A. Kisiel; L. Kochenda; D. D. Koetke; T. Kollegger; L. K. Kosarzewski; A. F. Kraishan; P. Kravtsov; K. Krueger; I. Kulakov; L. Kumar; R. A. Kycia; M. A. C. Lamont; J. M. Landgraf; K. D. Landry; J. Lauret; A. Lebedev; R. Lednicky; J. H. Lee; X. Li; Z. M. Li; Y. Li; W. Li; X. Li; C. Li; M. A. Lisa; F. Liu; T. Ljubicic; W. J. Llope; M. Lomnitz; R. S. Longacre; X. Luo; G. L. Ma; R. Ma; Y. G. Ma; L. Ma; N. Magdy; R. Majka; A. Manion; S. Margetis; C. Markert; H. Masui; H. S. Matis; D. McDonald; K. Meehan; N. G. Minaev; S. Mioduszewski; D. Mishra; B. Mohanty; M. M. Mondal; D. A. Morozov; M. K. Mustafa; B. K. Nandi; Md. Nasim; T. K. Nayak; G. Nigmatkulov; L. V. Nogach; S. Y. Noh; J. Novak; S. B. Nurushev; G. Odyniec; A. Ogawa; K. Oh; V. Okorokov; D. Olvitt Jr.; B. S. Page; R. Pak; Y. X. Pan; Y. Pandit; Y. Panebratsev; B. Pawlik; H. Pei; C. Perkins; A. Peterson; P. Pile; M. Planinic; J. Pluta; N. Poljak; K. Poniatowska; J. Porter; M. Posik; A. M. Poskanzer; J. Putschke; H. Qiu; A. Quintero; S. Ramachandran; R. Raniwala; S. Raniwala; R. L. Ray; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; A. Roy; L. Ruan; J. Rusnak; O. Rusnakova; N. R. Sahoo; P. K. Sahu; I. Sakrejda; S. Salur; J. Sandweiss; A. Sarkar; J. Schambach; R. P. Scharenberg; A. M. Schmah; W. B. Schmidke; N. Schmitz; J. Seger; P. Seyboth; N. Shah; E. Shahaliev; P. V. Shanmuganathan; M. Shao; M. K. Sharma; B. Sharma; W. Q. Shen; S. S. Shi; Q. Y. Shou; E. P. Sichtermann; R. Sikora; M. Simko; M. J. Skoby; N. Smirnov; D. Smirnov; L. Song; P. Sorensen; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; M. Stepanov; R. Stock; M. Strikhanov; B. Stringfellow; M. Sumbera; B. Summa; Z. Sun; X. M. Sun; Y. Sun; X. Sun; B. Surrow; N. Svirida; M. A. Szelezniak; Z. Tang; A. H. Tang; T. Tarnowsky; A. Tawfik; J. H. Thomas; A. R. Timmins; D. Tlusty; M. Tokarev; S. Trentalange; R. E. Tribble; P. Tribedy; S. K. Tripathy; B. A. Trzeciak; O. D. Tsai; T. Ullrich; D. G. Underwood; I. Upsal; G. Van Buren; G. van Nieuwenhuizen; M. Vandenbroucke; R. Varma; A. N. Vasiliev; R. Vertesi; F. Videbæk; Y. P. Viyogi; S. Vokal; S. A. Voloshin; A. Vossen; G. Wang; H. Wang; J. S. Wang; Y. Wang; Y. Wang; F. Wang; J. C. Webb; G. Webb; L. Wen; G. D. Westfall; H. Wieman; S. W. Wissink; R. Witt; Y. F. Wu; Z. G. Xiao; W. Xie; K. Xin; Y. F. Xu; Q. H. Xu; H. Xu; N. Xu; Z. Xu; Y. Yang; C. Yang; S. Yang; Y. Yang; Q. Yang; Z. Ye; P. Yepes; L. Yi; K. Yip; I. -K. Yoo; N. Yu; H. Zbroszczyk; W. Zha; J. B. Zhang; Z. Zhang; J. Zhang; S. Zhang; X. P. Zhang; J. Zhang; Y. Zhang; J. Zhao; C. Zhong; L. Zhou; X. Zhu; Y. Zoulkarneeva; M. Zyzak

    2015-05-28T23:59:59.000Z

    Collisions between prolate uranium nuclei are used to study how particle production and azimuthal anisotropies depend on initial geometry in heavy-ion collisions. We report the two- and four-particle cumulants, $v_2\\{2\\}$ and $v_2\\{4\\}$, for charged hadrons from U+U collisions at $\\sqrt{s_{\\rm NN}}$ = 193 GeV and Au+Au collisions at $\\sqrt{s_{\\rm NN}}$ = 200 GeV. Nearly fully overlapping collisions are selected based on the amount of energy deposited by spectators in the STAR Zero Degree Calorimeters (ZDCs). Within this sample, the observed dependence of $v_2\\{2\\}$ on multiplicity demonstrates that ZDC information combined with multiplicity can preferentially select different overlap configurations in U+U collisions. An initial-state model with gluon saturation describes the slope of $v_2\\{2\\}$ as a function of multiplicity in central collisions better than one based on Glauber with a two-component multiplicity model.

  17. Pressure-Induced Enhanced Magnetic Anisotropy in Mn(N(CN)2)2

    SciTech Connect (OSTI)

    Quintero, P. A. [University of Florida, Gainesville; Rajan, D. [University of Florida, Gainesville; Peprah, M. K. [University of Florida, Gainesville; Brinzari, T. V. [University of Florida, Gainesville; Fishman, Randy Scott [ORNL; Talham, Daniel R. [University of Florida, Gainesville; Meisel, Mark W. [University of Florida, Gainesville

    2015-01-01T23:59:59.000Z

    Using DC and AC magnetometry, the pressure dependence of the magnetization of the threedimensional antiferromagnetic coordination polymer Mn(N(CN)2)2 was studied up to 12 kbar and down to 8 K. The magnetic transition temperature, Tc, increases dramatically with applied pressure (P), where a change from Tc(P = ambient) = 16:0 K to Tc(P = 12:1 kbar) = 23:5 K was observed. In addition, a marked difference in the magnetic behavior is observed above and below 7.1 kbar. Specifically, for P < 7:1 kbar, the differences between the field-cooled and zero-field-cooled (fc-zfc) magnetizations, the coercive field, and the remanent magnetization decrease with increasing pressure. However, for P > 7:1 kbar, the behavior is inverted. Additionally, for P > 8:6 kbar, minor hysteresis loops are observed. All of these effects are evidence of the increase of the superexchange interaction and the appearance of an enhanced exchange anisotropy with applied pressure.

  18. The effect of temperature anisotropy on observations of Doppler dimming and pumping in the inner corona

    E-Print Network [OSTI]

    Xing Li; Shadia Rifai Habbal; John Kohl; Giancarlo Noci

    1998-05-04T23:59:59.000Z

    Recent observations of the spectral line profiles and intensity ratio of the O VI 1032 {\\AA} and 1037.6 {\\AA} doublet by the Ultraviolet Coronagraph Spectrometer (UVCS) on the Solar and Heliospheric Observatory (SOHO), made in coronal holes below 3.5 $R_s$, provide evidence for Doppler dimming of the O VI 1037.6 {\\AA} line and pumping by the chromospheric C II 1037.0182 {\\AA} line. Evidence for a significant kinetic temperature anisotropy of O$^{5+}$ ions was also derived from these observations. We show in this Letter how the component of the kinetic temperature in the direction perpendicular to the magnetic field, for both isotropic and anisotropic temperature distributions, affects both the amount of Doppler dimming and pumping. Taking this component into account, we further show that the observation that the O VI doublet intensity ratio is less than unity can be accounted for only if pumping by C II 1036.3367 {\\AA} in addition to C II 1037.0182 {\\AA} is in effect. The inclusion of the C II 1036.3367 {\\AA} pumping implies that the speed of the O$^{5+}$ ions can reach 400 km/s around 3 $R_s$ which is significantly higher than the reported UVCS values for atomic hydrogen in polar coronal holes. These results imply that oxygen ions flow much faster than protons at that heliocentric distance.

  19. Prediction of the Virgo axis anisotropy: CMB radiation illuminates the nature of things

    E-Print Network [OSTI]

    Simon Berkovich

    2005-09-25T23:59:59.000Z

    Recent findings of the anisotropy in the Cosmic Microwave Background (CMB) radiation are confusing for standard cosmology. Remarkably, this fact has been predicted several years ago in the framework of our model of the physical world. Moreover, in exact agreement with our prediction the CMB has a preferred direction towards the Virgo Cluster. The transpired structure of the CMB shows workings of the suggested model of the physical world. Comprising the information processes of Nature, this model presents a high-tech version of the previous low-tech developments for mechanical ether and quantum vacuum. In the current model, the phenomenon of Life turns up as a collective effect on the "Internet of the Physical Universe" using DNA structures for access codes. Most convincingly, this construction points to a harmful analogy with so-called "identity theft" - improper manipulations with DNA of individual organisms can destroy these organisms from a remote location without any physical contact. Appearing incredible, such a possibility creates a superlative Experimentum Crucis. In a broad sense, this surmised biological effect is intimately related to the cosmological prediction of the structurization of the CMB, but it is more compelling.

  20. Temperature dependence of magnetization and anisotropy in uniaxial NiFe{sub 2}O{sub 4} nanomagnets: Deviation from the Callen-Callen power law

    SciTech Connect (OSTI)

    Chatterjee, Biplab K.; Ghosh, C. K. [School of Materials Science and Nanotechnology, Jadavpur University, Jadavpur, Kolkata 700032 (India); Chattopadhyay, K. K., E-mail: kalyan-chattopadhyay@yahoo.com [School of Materials Science and Nanotechnology, Jadavpur University, Jadavpur, Kolkata 700032 (India); Thin Film and Nanoscience Laboratory, Department of Physics, Jadavpur University, Jadavpur, Kolkata 700032 (India)

    2014-10-21T23:59:59.000Z

    The thermal variation of magnetic anisotropy (K) and saturation magnetization (M{sub S}) for uniaxial nickel ferrite (NiFe{sub 2}O{sub 4}) nanomagnets are investigated. Major magnetic hysteresis loops are measured for the sample at temperatures over the range 5–280?K using a vibrating sample magnetometer. The high-field regimes of the hysteresis loops are modeled using the law of approach to saturation, based on the assumption that at sufficiently high field only direct rotation of spin-moment take place, with an additional forced magnetization term that is linear with applied field. The uniaxial anisotropy constant K is calculated from the fitting of the data to the theoretical equation. As temperature increases from 5?K to 280?K, a 49% reduction of K, accompanied by an 85% diminution of M{sub S} is observed. Remarkably, K is linearly proportional to M{sub S}{sup 2.6} in the whole temperature range violating the existing theoretical model by Callen and Callen. The unusual power-law behavior for the NiFe{sub 2}O{sub 4} uniaxial nanomagnets is ascribed to the non-negligible contributions from inter-sublattice pair interactions, Neel surface anisotropy, and higher order anisotropies. A complete realization of the unusual anisotropy-magnetization scaling behavior for nanoscale two-sublattice magnetic materials require a major modification of the existing theory by considering the exact mechanism of each contributions to the effective anisotropy.

  1. Tri-axial magnetic anisotropies in RE{sub 2}Ba{sub 4}Cu{sub 7}O{sub 15?y} superconductors

    SciTech Connect (OSTI)

    Horii, Shigeru, E-mail: horii.shigeru.7e@kyoto-u.ac.jp; Doi, Toshiya [Graduate School of Energy Science, Kyoto University, Yoshida-Honmachi, Sakyo-ku, Kyoto 606-8501 (Japan); Okuhira, Shota; Yamaki, Momoko [Department of Environmental Systems Engineering, Kochi University of Technology, Tosa-Yamada, Kami-shi, Kochi 782-8502 (Japan); Kishio, Kohji; Shimoyama, Jun-ichi [Department of Applied Chemistry, University of Tokyo, Bunkyo-ku, Tokyo 113-8656 (Japan)

    2014-03-21T23:59:59.000Z

    We report a novel quantification method of tri-axial magnetic anisotropy in orthorhombic substances containing rare earth (RE) ions using tri-axial magnetic alignment and tri-axial magnetic anisotropies depending on the type of RE in RE-based cuprate superconductors. From the changes in the axes for magnetization in magnetically aligned powders of (RE?{sub 1?x}RE?{sub x}){sub 2}Ba{sub 4}Cu{sub 7}O{sub y} [(RE?,RE?)247] containing RE ions with different single-ion magnetic anisotropies, the ratios of three-dimensional magnetic anisotropies between RE?247 and RE?247 could be determined. The results in (Y,Er)247, (Dy,Er)247, (Ho,Er)247, and (Y,Eu)247 systems suggest that magnetic anisotropies largely depended on the type of RE? (or RE?), even in the heavy RE ions with higher magnetic anisotropies. An appropriate choice of RE ions in RE-based cuprate superconductors enables the reduction of the required magnetic field for the production of their bulks and thick films based on the tri-axial magnetic alignment technique using modulated rotation magnetic fields.

  2. Physica D 159 (2001) 3557 Wave group dynamics in weakly nonlinear long-wave models

    E-Print Network [OSTI]

    Pelinovsky, Dmitry

    Physica D 159 (2001) 35­57 Wave group dynamics in weakly nonlinear long-wave models Roger Grimshawa Communicated by A.C. Newell Abstract The dynamics of wave groups is studied for long waves, using the framework reserved. Keywords: Wave group dynamics; Korteweg­de Vries equation; Nonlinear Schr¨odinger equation 1

  3. Gravity Wave Turbulence in Wave Tanks: Space and Time Statistics Sergei Lukaschuk,1,* Sergey Nazarenko,2

    E-Print Network [OSTI]

    Nazarenko, Sergey

    Gravity Wave Turbulence in Wave Tanks: Space and Time Statistics Sergei Lukaschuk,1,* Sergey the first simultaneous space-time measurements for gravity wave turbulence in a large laboratory flume. We found that the slopes of k and ! wave spectra depend on wave intensity. This cannot be explained by any

  4. CX-010213: Categorical Exclusion Determination

    Broader source: Energy.gov [DOE]

    Wave Energy Technology- New Zealand Multi-Mode Wave Energy Converter Advancement Project CX(s) Applied: A9 Date: 01/08/2013 Location(s): Hawaii, Oregon Offices(s): Golden Field Office

  5. Propagation Plane waves -High order Modes

    E-Print Network [OSTI]

    Berlin,Technische Universität

    1 Propagation · Plane waves - High order Modes y x a One wave: p(x,y,t)=p0 cos(k y)e-jk x e j t vy(y,t)= 0 ; y=0,a xy } ky = n a Propagation · Plane waves - High order Modes x n a p(x,y,t)=pn cos( y + - +- + + - +- + - + + +- - - (m,n) #12;4 Propagation · Circular duct ­ Helical waves (spiralling waves) kc=m/a kz k

  6. Propagation Plane waves -High order Modes

    E-Print Network [OSTI]

    Berlin,Technische Universität

    1 Propagation · Plane waves - High order Modes y x a ky = n a One wave: p(x,y,t)=p0 cos(k y)e-jk x e j t vy(y,t)= 0 ; y=0,a xy } Propagation · Plane waves - High order Modes x n a p(x,y,t)=pn cos( y;4 Propagation · Circular duct ­ Helical waves (spiralling waves) kc=m/a kz kH Projection: Propagation #12

  7. Relic Gravitational Waves and Limits on Inflation

    E-Print Network [OSTI]

    L. P. Grishchuk

    1993-04-14T23:59:59.000Z

    It is shown that only a narrow class of inflationary models can possibly agree with the available observational data on the anisotropy of the cosmic microwave background radiation (CMBR). These models may be governed by ``matter'' with the effective equation of state $-1.2

  8. Effects of ion abundances on electromagnetic ion cyclotron wave growth rate in the vicinity of the plasmapause

    SciTech Connect (OSTI)

    Henning, F. D., E-mail: farranalfonso@gmail.com; Mace, R. L., E-mail: macer@ukzn.ac.za [School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000 (South Africa)

    2014-04-15T23:59:59.000Z

    Electromagnetic ion cyclotron (EMIC) waves in multi-ion species plasmas propagate in branches. Except for the branch corresponding to the heaviest ion species, which has only a resonance at its gyrofrequency, these branches are bounded below by a cutoff frequency and above by a resonant gyrofrequency. The condition for wave growth is determined by the thermal anisotropies of each ion species, j, which sets an upper bound, ?{sub j}{sup ?}, on the wave frequency below which that ion species contributes positively to the growth rate. It follows that the relative positions of the cutoffs and the critical frequencies ?{sub j}{sup ?} play a crucial role in determining whether a particular wave branch will be unstable. The effect of the magnetospheric ion abundances on the growth rate of each branch of the EMIC instability in a model where all the ion species have kappa velocity distributions is investigated by appealing to the above ideas. Using the variation of the cutoff frequencies predicted by cold plasma theory as a guide, optimal ion abundances that maximise the EMIC instability growth rate are sought. When the ring current is comprised predominantly of H{sup +} ions, all branches of the EMIC wave are destabilised, with the proton branch having the maximum growth rate. When the O{sup +} ion abundance in the ring current is increased, a decrease in the growth rate of the proton branch and cyclotron damping of the helium branch are observed. The oxygen branch, on the other hand, experiences an increase in the maximum growth rate with an increase in the O{sup +} ion abundance. When the ring current is comprised predominantly of He{sup +} ions, only the helium and oxygen branches of the EMIC wave are destabilised, with the helium branch having the maximum growth rate.

  9. Wave-Turbulence Interactions in a Breaking Mountain Wave Craig Epifanio and Tingting Qian

    E-Print Network [OSTI]

    #12;Dissipation of Mean Wave Energy · Mean wave energy E is just the total energy (kinetic + available · The dissipation of mean wave energy is caused by the turbulent momentum fluxes--specifically, by their tendency

  10. Energy-momentum relation for solitary waves of relativistic wave equations

    E-Print Network [OSTI]

    T. V. Dudnikova; A. I. Komech; H. Spohn

    2005-08-23T23:59:59.000Z

    Solitary waves of relativistic invariant nonlinear wave equation with symmetry group U(1) are considered. We prove that the energy-momentum relation for spherically symmetric solitary waves coincides with the Einstein energy-momentum relation for point particles.

  11. Experimental studies of irregular water wave component interactions with comparisons to the hybrid wave model

    E-Print Network [OSTI]

    Longridge, Jonathon Kent

    1993-01-01T23:59:59.000Z

    Waves in the oceans pose challenging problems to offshore structural design because they arc irregular and can be highly nonlinear. Although these irregular waves can be viewed as the summation of many linear wave components of different...

  12. Cosmological Perturbations of Quantum-Mechanical Origin and Anisotropy of the Microwave Background

    E-Print Network [OSTI]

    L. P. Grishchuk

    1993-04-01T23:59:59.000Z

    Cosmological perturbations generated quantum-mechanically (as a particular case, during inflation) possess statistical properties of squeezed quantum states. The power spectra of the perturbations are modulated and the angular distribution of the produced temperature fluctuations of the CMBR is quite specific. An exact formula is derived for the angular correlation function of the temperature fluctuations caused by squeezed gravitational waves. The predicted angular pattern can, in principle, be revealed by the COBE-type observations.

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

    E-Print Network [OSTI]

    Spell, Charles Anthony

    1992-01-01T23:59:59.000Z

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

  14. Surface wave chemical detector using optical radiation

    DOE Patents [OSTI]

    Thundat, Thomas G.; Warmack, Robert J.

    2007-07-17T23:59:59.000Z

    A surface wave chemical detector comprising at least one surface wave substrate, each of said substrates having a surface wave and at least one measurable surface wave parameter; means for exposing said surface wave substrate to an unknown sample of at least one chemical to be analyzed, said substrate adsorbing said at least one chemical to be sensed if present in said sample; a source of radiation for radiating said surface wave substrate with different wavelengths of said radiation, said surface wave parameter being changed by said adsorbing; and means for recording signals representative of said surface wave parameter of each of said surface wave substrates responsive to said radiation of said different wavelengths, measurable changes of said parameter due to adsorbing said chemical defining a unique signature of a detected chemical.

  15. Two-wave interaction in ideal magnetohydrodynamics

    E-Print Network [OSTI]

    T. V. Zaqarashvili; B. Roberts

    2006-02-24T23:59:59.000Z

    The weakly nonlinear interaction of sound and linearly polarised Alfv{\\'e}n waves propagating in the same direction along an applied magnetic field is studied. It is found that a sound wave is coupled to the Alfv{\\'e}n wave with double period and wavelength when the sound and Alfv{\\'e}n speeds are equal. The Alfv{\\'e}n wave drives the sound wave through the ponderomotive force, while the sound wave returns energy back to the Alfv{\\'e}n wave through the parametric (swing) influence. As a result, the two waves alternately exchange their energy during propagation. The process of energy exchange is faster for waves with stronger amplitudes. The phenomenon can be of importance in astrophysical plasmas, including the solar atmosphere and solar wind.

  16. Global coherence of dust density waves

    SciTech Connect (OSTI)

    Killer, Carsten; Melzer, André [Institut für Physik, Ernst-Moritz-Arndt-Universität Greifswald, 17489 Greifswald (Germany)

    2014-06-15T23:59:59.000Z

    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.

  17. B8 Page 1 B8. Using CMS-Wave

    E-Print Network [OSTI]

    US Army Corps of Engineers

    B8 ­ Page 1 B8. Using CMS-Wave The most recent CMS-Wave code developed is Version 3.2. Several new capabilities and advanced features in this version include: · Full-plane wind-generation of waves · Automatic wave run-up calculation · Infra-gravity wave calculation · Nonlinear wave-wave interaction · Muddy

  18. Nanosecond electro-optics of nematic liquid crystal with negative dielectric anisotropy

    E-Print Network [OSTI]

    Volodymyr Borshch; Sergij V. Shiyanovskii; Bing-Xiang Li; Oleg D. Lavrentovich

    2014-11-22T23:59:59.000Z

    We study a nanosecond electro-optic response of a nematic liquid crystal in a geometry where an applied electric field $\\textbf{E}$ modifies the tensor order parameter but does not change the orientation of the optic axis (director $\\hat{\\textbf{N}}$). We use a nematic with negative dielectric anisotropy with the electric field applied perpendicularly to $\\hat{\\textbf{N}}$. The field changes the dielectric tensor at optical frequencies (optic tensor) due to the following mechanisms: (a) nanosecond creation of the biaxial orientational order; (b) uniaxial modification of the orientational order that occurs over timescales of tens of nanoseconds, and (c) the quenching of director fluctuations with a wide range of characteristic times up to milliseconds. We develop a model to describe the dynamics of all three mechanisms. We design the experimental conditions to selectively suppress the contributions from fluctuations quenching (c) and from the biaxial order effect (a) and thus, separate the contributions of the three mechanisms in the electro-optic response. As a result, the experimental data can be well fitted with the model. The analysis provides a detailed physical picture of how the liquid crystal responds to a strong electric field on a timescale of nanoseconds. This work provides a useful guide in the current search of the biaxial nematic phase. Namely, the temperature dependence of the biaxial susceptibility allows one to estimate the temperature of the potential uniaxial-to-biaxial phase transition. An analysis of the fluctuations quenching indicates that on a timescale of nanoseconds, the classic model with constant viscoelastic material parameters might reach its limit of validity. The effect of nanosecond electric modification of the order parameter (NEMOP) can be used in applications in which one needs to achieve ultrafast (nanosecond) changes of optical characteristics.

  19. IMPROVED CONSTRAINTS ON PRIMORDIAL NON-GAUSSIANITY FOR THE WILKINSON MICROWAVE ANISOTROPY PROBE 5-YEAR DATA

    SciTech Connect (OSTI)

    Curto, A.; Martinez-Gonzalez, E.; Barreiro, R. B., E-mail: curto@ifca.unican.e [IFCA, CSIC-Univ. de Cantabria, Avda. los Castros, s/n, E-39005-Santander (Spain)

    2009-11-20T23:59:59.000Z

    We present constraints on the nonlinear coupling parameter f{sub nl} with the Wilkinson Microwave Anisotropy Probe (WMAP) data. We use an updated method based on the spherical Mexican hat wavelet (SMHW) which provides improved constraints on the f{sub nl} parameter. This paper is a continuation of a previous work by Curto et al., where several third-order statistics based on the SMHW were considered. In this paper, we use all the possible third-order statistics computed from the wavelet coefficient maps evaluated at 12 angular scales. The scales are logarithmically distributed from 6.9 arcmin to 500 arcmin. Our analysis indicates that f{sub nl} is constrained to -18 < f{sub nl} < +80 at 95% confidence level (CL) for the combined V+W WMAP map. This value has been corrected by the presence of undetected point sources, which adds a positive contribution of DELTAf{sub nl} = 6 +- 5. Our result excludes at approx99% CL the best-fitting value f{sub nl} = 87 reported by Yadav and Wandelt. We have also constrained f{sub nl} for the Q, V, and W frequency bands separately, finding compatibility with zero at 95% CL for the Q and V bands but not for the W band. We have performed some further tests to understand the cause of this deviation which indicate that systematics associated with the W radiometers could be responsible for this result. Finally, we have performed a Galactic north-south analysis for f{sub nl}. We have not found any asymmetry, i.e., the best-fitting f{sub nl} for the northern pixels is compatible with the best-fitting f{sub nl} for the southern pixels.

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

    SciTech Connect (OSTI)

    Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

    2012-12-15T23:59:59.000Z

    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.

  1. Wave propagation in anisotropic viscoelasticity

    E-Print Network [OSTI]

    Andrzej Hanyga

    2015-04-30T23:59:59.000Z

    We extend the theory of complete Bernstein functions to matrix-valued functions and apply it to analyze Green's function of an anisotropic multi-dimension\\-al linear viscoelastic problem. Green's function is given by the superposition of plane waves. Each plane wave is expressed in terms of matrix-valued attenuation and dispersion functions given in terms of a matrix-valued positive semi-definite Radon measure. More explicit formulae are obtained for 3D isotropic viscoelastic Green's functions. As an example of an anisotropic medium the transversely isotropic medium with a constant symmetry axis is considered.

  2. Wave Energy | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are beingZealand Jump to:Ezfeedflag JumpID-fTri GlobalJump to: navigation,Goff, 2002) | OpenEnergy AS Jump to:WaveWave

  3. atmospheric gravity waves: Topics by E-print Network

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

    gravity waves (AGWs). Satellite imagery shows evidence the characteristics of these waves. The favorable wave propagation conditions in 12;this region are illustrated 5...

  4. anomalous spin waves: Topics by E-print Network

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

    branches of wave dispersion: spin-electromagnetic plasma waves and self-consistent spin waves. Propagation of neutron beams through quantum plasmas is also considered....

  5. Identifying two steps in the internal wave energy cascade

    E-Print Network [OSTI]

    Sun, Oliver Ming-Teh

    2010-01-01T23:59:59.000Z

    1.1.1 The internal wave energy cascade . . . . . . .? ? , which contain only wave energy trav- eling upward anddistinction is made between wave energy propagating upward

  6. Fundamentals of Traveling Wave Ion Mobility Spectrometry. | EMSL

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

    Fundamentals of Traveling Wave Ion Mobility Spectrometry. Fundamentals of Traveling Wave Ion Mobility Spectrometry. Abstract: Traveling-wave ion mobility spectrometry (TW IMS) is a...

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

    Open Energy Info (EERE)

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

  8. alfven wave spectrum: Topics by E-print Network

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

    waves are easily excited by various processes. Linear waves propagate at the Alfv'en speed v Guedel, Manuel 14 Anisotropic weak turbulence of Alfven waves in collisionless...

  9. alfven wave avalanches: Topics by E-print Network

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

    waves are easily excited by various processes. Linear waves propagate at the Alfv'en speed v Guedel, Manuel 13 Anisotropic weak turbulence of Alfven waves in collisionless...

  10. Multicomponent seismic data, combining P-wave and converted P-to-SV wave (C-wave) wavefields, provide inde-

    E-Print Network [OSTI]

    Texas at Austin, University of

    (fast and slow) with differing polarization. The 4C, 3D ocean-bottom cable (OBC) multicomponent seismic and stratigraphic features within the gas-charged intervals. C- waves (Figure 3) penetrate these P-wave wipeout

  11. Wave VelocityWave Velocity Diff t f ti l l itDifferent from particle velocity

    E-Print Network [OSTI]

    Yoo, S. J. Ben

    Wave VelocityWave Velocity v=/T =f Diff t f ti l l itDifferent from particle velocity Depends on the medium in which the wave travelsDepends on the medium in which the wave travels stringaonvelocity F v of Waves11-8. Types of Waves Transverse wave Longitudinal wave Liu UCD Phy1B 2014 37 #12;Sound Wave

  12. Dynamic response of phenolic resin and its carbon-nanotube composites to shock wave loading

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

    Arman, B. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States) and Texas A and M Univ., College Station, TX (United States); An, Q. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States) and California Institute of Technology, Pasedena, CA (United States); Luo, S. N. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Desai, T. G. [Advanced Cooling Technologies, Inc., Lancaster, PA (United States); Tonks, D. L. [Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Cagin, T. [Texas A and M Univ., College Station, TX (United States); Goddard III, W. A. [California Institute of Technology, Pasedena, CA (United States)

    2011-01-01T23:59:59.000Z

    We investigate with nonreactive molecular dynamics simulations the dynamic response of phenolic resin and its carbon-nanotube (CNT) composites to shock wave compression. For phenolic resin, our simulations yield shock states in agreement with experiments on similar polymers except the “phase change” observed in experiments, indicating that such phase change is chemical in nature. The elastic–plastic transition is characterized by shear stress relaxation and atomic-level slip, and phenolic resin shows strong strain hardening. Shock loading of the CNT-resin composites is applied parallel or perpendicular to the CNT axis, and the composites demonstrate anisotropy in wave propagation, yield and CNT deformation. The CNTs induce stress concentrations in the composites and may increase the yield strength. Our simulations suggest that the bulk shock response of the composites depends on the volume fraction, length ratio, impact cross-section, and geometry of the CNT components; the short CNTs in current simulations have insignificant effect on the bulk response of resin polymer.

  13. Dynamic response of phenolic resin and its carbon-nanotube composites to shock wave loading

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

    Arman, B.; An, Q.; Luo, S. N.; Desai, T. G.; Tonks, D. L.; Cagin, T.; Goddard III, W. A.

    2011-01-01T23:59:59.000Z

    We investigate with nonreactive molecular dynamics simulations the dynamic response of phenolic resin and its carbon-nanotube (CNT) composites to shock wave compression. For phenolic resin, our simulations yield shock states in agreement with experiments on similar polymers except the “phase change” observed in experiments, indicating that such phase change is chemical in nature. The elastic–plastic transition is characterized by shear stress relaxation and atomic-level slip, and phenolic resin shows strong strain hardening. Shock loading of the CNT-resin composites is applied parallel or perpendicular to the CNT axis, and the composites demonstrate anisotropy in wave propagation, yield and CNT deformation. Themore »CNTs induce stress concentrations in the composites and may increase the yield strength. Our simulations suggest that the bulk shock response of the composites depends on the volume fraction, length ratio, impact cross-section, and geometry of the CNT components; the short CNTs in current simulations have insignificant effect on the bulk response of resin polymer.« less

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

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01T23:59:59.000Z

    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,

  15. Einstein, Black Holes Gravitational Waves

    E-Print Network [OSTI]

    Cook, Greg

    1 #12;Einstein, Black Holes and Gravitational Waves Gregory B. Cook Wake Forest University 2 #12;Einstein's Miraculous Year: 1905 · Einstein, A. "¨Uber einen die Erzeugung und Verwandlung des Lichtes Concerning the Production and Transformation of Light. · Einstein, A. "¨Uber die von der molekularkinetischen

  16. Wave functions of linear systems

    E-Print Network [OSTI]

    Tomasz Sowinski

    2007-06-05T23:59:59.000Z

    Complete analysis of quantum wave functions of linear systems in an arbitrary number of dimensions is given. It is shown how one can construct a complete set of stationary quantum states of an arbitrary linear system from purely classical arguments. This construction is possible because for linear systems classical dynamics carries the whole information about quantum dynamics.

  17. Nonlinear Saturation of Vertically Propagating Rossby Waves

    E-Print Network [OSTI]

    Giannitsis, Constantine

    The interaction between vertical Rossby wave propagation and wave breaking is studied in the idealized context of a beta-plane channel model. Considering the problem of propagation through a uniform zonal flow in an ...

  18. Arnold Schwarzenegger DEVELOPING WAVE ENERGY IN

    E-Print Network [OSTI]

    Arnold Schwarzenegger Governor DEVELOPING WAVE ENERGY IN COASTAL CALIFORNIA: POTENTIAL SOCIO. Developing Wave Energy In Coastal California: Potential Socio-Economic And Environmental Effects. California-ECONOMIC AND ENVIRONMENTAL EFFECTS Prepared For: California Energy Commission Public Interest Energy Research Program

  19. Mathematical aspects of surface water waves

    E-Print Network [OSTI]

    Craig, Walter

    questions remain. These have to do with the evolution of surface water waves, their approximation by model normally being chosen. Unless we are describing waves of a global extent, such as a tsunami, for our

  20. Fracture compliance estimation using borehole tube waves

    E-Print Network [OSTI]

    Bakku, Sudhish Kumar

    We tested two models, one for tube-wave generation and the other for tube-wave attenuation at a fracture intersecting a borehole that can be used to estimate fracture compliance, fracture aperture, and lateral extent. In ...

  1. On quantization of nondispersive wave packets

    SciTech Connect (OSTI)

    Altaisky, M. V. [Space Research Institute RAS, Profsoyuznaya 84/32, Moscow 117997 (Russian Federation)] [Space Research Institute RAS, Profsoyuznaya 84/32, Moscow 117997 (Russian Federation); Kaputkina, N. E. [National University of Science and Technology “MISIS” Leninsky prospect 4, Moscow 119049 (Russian Federation)] [National University of Science and Technology “MISIS” Leninsky prospect 4, Moscow 119049 (Russian Federation)

    2013-10-15T23:59:59.000Z

    Nondispersive wave packets are widely used in optics and acoustics. We found it interesting that such packets could be also a subject of quantum field theory. Canonical commutation relations for the nondispersive wave packets are constructed.

  2. Wave Mechanics and General Relativity: A Rapprochement

    E-Print Network [OSTI]

    Paul S. Wesson

    2006-01-16T23:59:59.000Z

    Using exact solutions, we show that it is in principle possible to regard waves and particles as representations of the same underlying geometry, thereby resolving the problem of wave-particle duality.

  3. Wind effects on shoaling wave shape

    E-Print Network [OSTI]

    Feddersen, F; Veron, F

    2005-01-01T23:59:59.000Z

    breaking in the presence of wind drift and swell. J. Fluidlin, 1995: Asymmetry of wind waves studied in a laboratorycoupling between swell and wind-waves. J. Phys. Oceanogr. ,

  4. Carbon nanotube-guided thermopower waves

    E-Print Network [OSTI]

    Choi, Wonjoon

    Thermopower waves are a new concept for the direct conversion of chemical to electrical energy. A nanowire with large axial thermal diffusivity can accelerate a self-propagating reaction wave using a fuel coated along its ...

  5. Oblique reflections of internal gravity wave beams

    E-Print Network [OSTI]

    Karimi, Hussain H. (Hussain Habibullah)

    2012-01-01T23:59:59.000Z

    We study nonlinear effects in reflections of internal gravity wave beams in a continuously stratified liquid which are incident upon a uniform slope at an oblique angle. Wave motion in a stratified fluid medium is unique ...

  6. Turbulent round jet under gravity waves

    E-Print Network [OSTI]

    Ryu, Yong Uk

    2002-01-01T23:59:59.000Z

    The behavior of a neutrally buoyant horizontal turbulent round jet under a wavy environment was investigated. Progressive waves with different wave amplitudes in an intermediate water depth were used. The Particle Image Velocimetry (PIV) technique...

  7. Gravitational waves from merging compact binaries

    E-Print Network [OSTI]

    Hughes, Scott A.

    Largely motivated by the development of highly sensitive gravitational-wave detectors, our understanding of merging compact binaries and the gravitational waves they generate has improved dramatically in recent years. ...

  8. Analysis of optimum Lamb wave tuning

    E-Print Network [OSTI]

    Shi, Yijun, 1970-

    2002-01-01T23:59:59.000Z

    Guided waves are of enormous interest in the nondestructive evaluation of thin-walled structures and layered media. Due to their dispersive and multi-modal nature, it is desirable to tune the waves by discriminating one ...

  9. Dielectron Azimuthal Anisotropy at mid-rapidity in Au+Au collisions at root s=200GeV

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

    Adamczyk, L. [AGH University of Science and Technology, Cracow (Poland); STAR Collaboration

    2014-12-01T23:59:59.000Z

    We report on the first measurement of the azimuthal anisotropy (v?) of dielectrons (e?e? pairs) at mid-rapidity from ?(sNN)=200 GeV Au + Au collisions with the STAR detector at the Relativistic Heavy Ion Collider (RHIC), presented as a function of transverse momentum (pT) for different invariant-mass regions. In the mass region Meeee<2.9GeV/c², the measured dielectron v? is consistent, within experimental uncertainties, with that from the cc¯ contributions.

  10. Wave-driven Countercurrent Plasma Centrifuge

    SciTech Connect (OSTI)

    A.J. Fetterman and N.J. Fisch

    2009-03-20T23:59:59.000Z

    A method for driving rotation and a countercurrent flow in a fully ionized plasma centrifuge is described. The rotation is produced by radiofrequency waves near the cyclotron resonance. The wave energy is transferred into potential energy in a manner similar to the ? channeling effect. The countercurrent flow may also be driven by radiofrequency waves. By driving both the rotation and the flow pattern using waves instead of electrodes, physical and engineering issues may be avoided.

  11. Wave Propagation in Fractured Poroelastic Media

    E-Print Network [OSTI]

    Seismic wave propagation through fractures and cracks is an important subject in exploration and production geophysics, earthquake seismology and mining.

  12. Energy- and flux-budget turbulence closure model for stably stratified flows. Part II: the role of internal gravity waves

    E-Print Network [OSTI]

    S. S. Zilitinkevich; T. Elperin; N. Kleeorin; V. L'vov; I. Rogachevskii

    2009-08-18T23:59:59.000Z

    We advance our prior energy- and flux-budget turbulence closure model (Zilitinkevich et al., 2007, 2008) for the stably stratified atmospheric flows and extend it accounting for additional vertical flux of momentum and additional productions of turbulent kinetic energy, turbulent potential energy (TPE) and turbulent flux of potential temperature due to large-scale internal gravity waves (IGW). Main effects of IGW are following: the maximal value of the flux Richardson number (universal constant 0.2-0.25 in the no-IGW regime) becomes strongly variable. In the vertically homogeneous stratification, it increases with increasing wave energy and can even exceed 1. In the heterogeneous stratification, when IGW propagate towards stronger stratification, the maximal flux Richardson number decreases with increasing wave energy, reaches zero and then becomes negative. In other words, the vertical flux of potential temperature becomes counter-gradient. IGW also reduce anisotropy of turbulence and increase the share of TPE in the turbulent total energy. Depending on the direction (downward or upward), IGW either strengthen or weaken the total vertical flux of momentum. Predictions from the proposed model are consistent with available data from atmospheric and laboratory experiments, direct numerical simulations and large-eddy simulations.

  13. Comparison of P-wave and S-wave data processed by DIP moveout

    E-Print Network [OSTI]

    Al-Misnid, Abdulaziz Mugbel

    1994-01-01T23:59:59.000Z

    of compressional (P) and shear (S) wave data in a fractured reservoir can show whether amplitude anomalies on the P-wave section are associated with the presence of gas or change of lithology. The P-wave and S-wave data selected for this study were shot in Burleson...

  14. High amplitude wave propagation in collapsible tubes. II. Forerunners and high amplitude waves

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    773 High amplitude wave propagation in collapsible tubes. II. Forerunners and high amplitude waves that, under certain circumstances, a pressure wave of large amplitude which propagates in a fluid feature of such a shock wave propagation inside an initially collapsed tube is the presence ofwavelets

  15. Thompson/Ocean 420/Winter 2004 2D waves 1 Two-dimensional wave propagation

    E-Print Network [OSTI]

    Thompson, LuAnne

    Thompson/Ocean 420/Winter 2004 2D waves 1 Two-dimensional wave propagation So far we have talked about wave propagation in one-dimension. For two or three spatial dimensions, we vectorize our ideas propagation. For surface waves, there is no vertical propagation, and we are only concerned with the two

  16. WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu

    E-Print Network [OSTI]

    WAVE HEIGHTS IN A 4D OCEAN WAVE FIELD Paul C. Liu NOAA Great Lakes Environmental Research a preliminary examination and analysis of a small suite of 4-D wave data to explore what new insight century. We feel it is timely to encourage further 4-D ocean wave measurement and thereby facilitate fresh

  17. Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1

    E-Print Network [OSTI]

    Showalter, Kenneth

    Wave Front Interaction Model of Stabilized Propagating Wave Segments Vladimir S. Zykov1 and Kenneth; published 14 February 2005) A wave front interaction model is developed to describe the relationship between excitability and the size and shape of stabilized wave segments in a broad class of weakly excitable media

  18. Wave Turbulence in Superfluid 4 Energy Cascades, Rogue Waves & Kinetic Phenomena

    E-Print Network [OSTI]

    Fominov, Yakov

    Outline Wave Turbulence in Superfluid 4 He: Energy Cascades, Rogue Waves & Kinetic Phenomena Conference, Chernogolovka, 3 August 2009 McClintock Efimov Ganshin Kolmakov Mezhov-Deglin Wave Turbulence in Superfluid 4 He #12;Outline Outline 1 Introduction Motivation 2 Modelling wave turbulence Need for models

  19. Wave-pinned filaments of scroll waves Tams Bnsgi, Jr., Kevin J. Meyer, and Oliver Steinbocka

    E-Print Network [OSTI]

    Steinbock, Oliver

    Wave-pinned filaments of scroll waves Tamás Bánsági, Jr., Kevin J. Meyer, and Oliver Steinbocka Received 5 November 2007; accepted 26 December 2007; published online 6 March 2008 Scroll waves are three can be pinned to the wake of traveling wave pulses. This pinning is studied in experiments with the 1

  20. Measurement of sound speed vs. depth in South Pole ice: pressure waves and shear waves

    E-Print Network [OSTI]

    Klein, Spencer

    2010-01-01T23:59:59.000Z

    waves generated by the thermoacoustic mechanism, little workproduction by the thermoacoustic mechanism is suppressed,

  1. Wave Impact Study on a Residential Building Wave Impact Study on a Residential Building

    E-Print Network [OSTI]

    Cox, Dan

    Wave Impact Study on a Residential Building Paper: Wave Impact Study on a Residential Building John residential light- frame wood buildings and wave and surge loading be- cause often little is left residential structures and wave loading. To do this, one-sixth scale residen- tial building models typical

  2. Beauty waves: an artistic representation of ocean waves using Bezier curves

    E-Print Network [OSTI]

    Faulkner, Jay Allen

    2007-04-25T23:59:59.000Z

    In this thesis, we present a method for computing an artistic representation of ocean waves using Bezier curves. Wave forms are loosely based on procedural wave models and are designed to emulate those found in both art and nature. The wave forms...

  3. Autoresonance of coupled nonlinear waves L. Friedland

    E-Print Network [OSTI]

    Friedland, Lazar

    wave train solutions of the decoupled problem. At the same time, the waves are globally phase locked, allowing the continuation of the phase locking between the waves despite the variation of system's param and sustaining this multidimensional autoresonance are the internal reso- nant excitation of one of the coupled

  4. EFFECTS OF SOUND WAVES ON YOUNG SALMON

    E-Print Network [OSTI]

    EFFECTS OF SOUND WAVES ON YOUNG SALMON Marine Biological Laboratory X. 1 33 R A. RTT ir.':; WOODS instantaneously to sounds. It was con- were tested in an experimental tank and in eluded that sound waves were, Wash . sound studies conducted under the above contract are terminated. #12;EFFECTS OF SOUND WAVES

  5. Coupled Parabolic Equations for Wave Propagation

    E-Print Network [OSTI]

    Zhao, Hongkai

    Coupled Parabolic Equations for Wave Propagation Kai Huang, Knut Solna and Hongkai Zhao #3; April simulation of wave propagation over long distances. The coupled parabolic equations are derived from a two algorithms are important in order to understand wave propagation in complex media. Resolving the wavelength

  6. Solitary waves propagating over variable Roger Grimshaw

    E-Print Network [OSTI]

    Solitary waves propagating over variable topography Roger Grimshaw Loughborough University waves that can propagate steadily over long distances. They were first observed by Russell in 1837 in a now famous report [26] on his observations of a solitary wave propagating along a Scottish canal

  7. Seminario de Matemtica Aplicada "Renowable wave energy

    E-Print Network [OSTI]

    Tradacete, Pedro

    Seminario de Matemática Aplicada "Renowable wave energy: potencial and technical challenges Abstract: Among the various renewable energy sources, ocean wave energy has been only recently investiga will be at first to introduce the potential of wave energy, as a significant, and often neglected, contributor

  8. Wave propagation Remco Hartkamp (University of Twente)

    E-Print Network [OSTI]

    Entekhabi, Dara

    ) waves Sound: 20 Hz ­ 20 kHz Gas: P Liquid: P Plasma: P Solid: P & S #12;Stretched string example 1D wave Dispersion: Waves with different wavelengths propagate at different speeds 6 k c k k Shallow water: c gh mJ K material parameter (related to the strain saturation of the material) det FJ bulk modulus

  9. Multi-reflective acoustic wave device

    DOE Patents [OSTI]

    Andle, Jeffrey C.

    2006-02-21T23:59:59.000Z

    An acoustic wave device, which utilizes multiple localized reflections of acoustic wave for achieving an infinite impulse response while maintaining high tolerance for dampening effects, is disclosed. The device utilized a plurality of electromechanically significant electrodes disposed on most of the active surface. A plurality of sensors utilizing the disclosed acoustic wave mode device are also described.

  10. Wave guides: vacuum w/ tube of conductor

    E-Print Network [OSTI]

    Hart, Gus

    Wave guides: vacuum w/ tube of conductor boundary conditions for conductor Properties: non-transverse waves except TEM mode in coaxial cable speed normal modes (from Liouville problem) TE or TM TEM for coaxial cable cuto frequency otherwise evanescent waves separation into and components with 1 #12;B

  11. WAVE GENERATIONS FROM CONFINED EXPLOSIONS IN ROCKS

    E-Print Network [OSTI]

    Stewart, Sarah T.

    WAVE GENERATIONS FROM CONFINED EXPLOSIONS IN ROCKS C. L. Liu and Thomas J. Ahrens Seismological Laboratory, California Institute of Technology, Pasadena, CA 91125 In order to record P- and S-waves on the interactions between incident P- and SV-waves and free-surfaces of rocks. The relations between particle

  12. Wave Packets and Turbulent Peter Jordan1

    E-Print Network [OSTI]

    Dabiri, John O.

    Wave Packets and Turbulent Jet Noise Peter Jordan1 and Tim Colonius2 1 D´epartement Fluides-control efforts is incomplete. Wave packets are intermittent, advecting disturbances that are correlated over review evidence of the existence, energetics, dynamics, and acous- tic efficiency of wave packets. We

  13. EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR

    E-Print Network [OSTI]

    Karney, Charles

    EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY RELATIVISTIC PLASMA by S.C. CHIU, C.F.F. KARNEY: http://charles.karney.info/biblio/chiu94.html #12;Chiu e t al. THE EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY RELATIVISTIC PLASMA THE EFFICIENCY OF FAST WAVE CURRENT DRIVE FOR A WEAKLY

  14. Visualizing the kinematics of relativistic wave packets

    E-Print Network [OSTI]

    Bernd Thaller

    2004-09-14T23:59:59.000Z

    This article investigates some solutions of the time-dependent free Dirac equation. Visualizations of these solutions immediately reveal strange phenomena that are caused by the interference of positive- and negative-energy waves. The effects discussed here include the Zitterbewegung, the opposite direction of momentum and velocity in negative-energy wave packets, and the superluminal propagation of the wave packet's local maxima.

  15. Hybrid wave model and its applications

    E-Print Network [OSTI]

    Yang, Jun

    1998-01-01T23:59:59.000Z

    A nonlinear hybrid wave model (HWM) is developed. It uses the conventional mode-coupling method (MCM) and the phase modulation method (PMM) to address the nonlinear interactions between free-wave components in an ocean wave field. The PMM is a...

  16. Airborne observations of the kinematics and statistics of breaking waves

    E-Print Network [OSTI]

    Kleiss, Jessica M.

    2009-01-01T23:59:59.000Z

    E. M. Janssen, 1996: Wave energy dissipation by whitecaps.waves: Surface impulse and wave energy dissipation rates. J.to the ocean, dissipating wave energy that is then available

  17. ITB KNAW UTwente Lectures on Free Surface Waves

    E-Print Network [OSTI]

    Al Hanbali, Ahmad

    , Acknowledgment Surface waves are phenomena that are characterised by the dynamic interplay between linear.3 Linear Dispersive wave model . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 1.4 Wave groupsITB KNAW UTwente Lectures on Free Surface Waves Brenny van Groesen, Applied Analysis & Mathematical

  18. Traveling wave device for combining or splitting symmetric and asymmetric waves

    DOE Patents [OSTI]

    Möbius, Arnold (Eggenstein, DE); Ives, Robert Lawrence (Saratoga, CA)

    2005-07-19T23:59:59.000Z

    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.

  19. Wave turbulent statistics in non-weak wave turbulence

    E-Print Network [OSTI]

    Naoto Yokoyama

    2011-05-08T23:59:59.000Z

    In wave turbulence, it has been believed that statistical properties are well described by the weak turbulence theory, in which nonlinear interactions among wavenumbers are assumed to be small. In the weak turbulence theory, separation of linear and nonlinear time scales derived from the weak nonlinearity is also assumed. However, the separation of the time scales is often violated even in weak turbulent systems where the nonlinear interactions are actually weak. To get rid of this inconsistency, closed equations are derived without assuming the separation of the time scales in accordance with Direct-Interaction Approximation (DIA), which has been successfully applied to Navier--Stokes turbulence. The kinetic equation of the weak turbulence theory is recovered from the DIA equations if the weak nonlinearity is assumed as an additional assumption. It suggests that the DIA equations is a natural extension of the conventional kinetic equation to not-necessarily-weak wave turbulence.

  20. Measurement of the Azimuthal Anisotropy of Neutral Pions in Pb-Pb Collisions at ?sNN=2.76??TeV

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

    Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.; Dragicevic, M.; Erö, J.; Fabjan, C.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Hammer, J.; Hörmann, N.; Hrubec, J.; Jeitler, M.; Kiesenhofer, W.; Knünz, V.; Krammer, M.; Krätschmer, I.; Liko, D.; Mikulec, I.; Pernicka, M.; Rahbaran, B.; Rohringer, C.; Rohringer, H.; Schöfbeck, R.; Strauss, J.; Taurok, A.; Waltenberger, W.; Walzel, G.; Widl, E.; Wulz, C.-E.; Mossolov, V.; Shumeiko, N.; Suarez Gonzalez, J.; Bansal, S.; Cornelis, T.; De Wolf, E. A.; Janssen, X.; Luyckx, S.; Mucibello, L.; Ochesanu, S.; Roland, B.; Rougny, R.; Selvaggi, M.; Staykova, Z.; Van Haevermaet, H.; Van Mechelen, P.; Van Remortel, N.; Van Spilbeeck, A.; Blekman, F.; Blyweert, S.; D’Hondt, J.; Gonzalez Suarez, R.; Kalogeropoulos, A.; Maes, M.; Olbrechts, A.; Van Doninck, W.; Van Mulders, P.; Van Onsem, G. P.; Villella, I.; Clerbaux, B.; De Lentdecker, G.; Dero, V.; Gay, A. P. R.; Hreus, T.; Léonard, A.; Marage, P. E.; Reis, T.; Thomas, L.; Vander Marcken, G.; Vander Velde, C.; Vanlaer, P.; Wang, J.; Adler, V.; Beernaert, K.; Cimmino, A.; Costantini, S.; Garcia, G.; Grunewald, M.; Klein, B.; Lellouch, J.; Marinov, A.; Mccartin, J.; Ocampo Rios, A. A.; Ryckbosch, D.; Strobbe, N.; Thyssen, F.; Tytgat, M.; Verwilligen, P.; Walsh, S.; Yazgan, E.; Zaganidis, N.; Basegmez, S.; Bruno, G.; Castello, R.; Ceard, L.; Delaere, C.; du Pree, T.; Favart, D.; Forthomme, L.; Giammanco, A.; Hollar, J.; Lemaitre, V.; Liao, J.; Militaru, O.; Nuttens, C.; Pagano, D.; Pin, A.; Piotrzkowski, K.; Schul, N.; Vizan Garcia, J. M.; Beliy, N.; Caebergs, T.; Daubie, E.; Hammad, G. H.; Alves, G. A.; Correa Martins Junior, M.; De Jesus Damiao, D.; Martins, T.; Pol, M. E.; Souza, M. H. G.; Aldá Júnior, W. L.; Carvalho, W.; Custódio, A.; Da Costa, E. M.; De Oliveira Martins, C.; Fonseca De Souza, S.; Matos Figueiredo, D.; Mundim, L.; Nogima, H.; Oguri, V.; Prado Da Silva, W. L.; Santoro, A.; Soares Jorge, L.; Sznajder, A.; Anjos, T. S.; Bernardes, C. A.; Dias, F. A.; Fernandez Perez Tomei, T. R.; Gregores, E. M.; Lagana, C.; Marinho, F.; Mercadante, P. G.; Novaes, S. F.; Padula, Sandra S.; Genchev, V.; Iaydjiev, P.; Piperov, S.; Rodozov, M.; Stoykova, S.; Sultanov, G.; Tcholakov, V.; Trayanov, R.; Vutova, M.; Dimitrov, A.; Hadjiiska, R.; Kozhuharov, V.; Litov, L.; Pavlov, B.; Petkov, P.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Jiang, C. H.; Liang, D.; Liang, S.; Meng, X.; Tao, J.; Wang, J.; Wang, X.; Wang, Z.; Xiao, H.; Xu, M.; Zang, J.; Zhang, Z.; Asawatangtrakuldee, C.; Ban, Y.; Guo, S.; Guo, Y.; Li, W.; Liu, S.; Mao, Y.; Qian, S. J.; Teng, H.; Wang, D.; Zhang, L.; Zhu, B.; Zou, W.; Avila, C.; Gomez, J. P.; Gomez Moreno, B.; Osorio Oliveros, A. F.; Sanabria, J. C.; Godinovic, N.; Lelas, D.; Plestina, R.; Polic, D.; Puljak, I.; Antunovic, Z.; Kovac, M.; Brigljevic, V.; Duric, S.; Kadija, K.; Luetic, J.; Morovic, S.; Attikis, A.; Galanti, M.; Mavromanolakis, G.; Mousa, J.; Nicolaou, C.; Ptochos, F.; Razis, P. A.; Finger, M.; Finger, M.; Assran, Y.; Elgammal, S.; Ellithi Kamel, A.; Khalil, S.; Mahmoud, M. A.; Radi, A.; Kadastik, M.; Müntel, M.; Raidal, M.; Rebane, L.; Tiko, A.; Eerola, P.; Fedi, G.; Voutilainen, M.; Härkönen, J.; Heikkinen, A.; Karimäki, V.; Kinnunen, R.; Kortelainen, M. J.; Lampén, T.; Lassila-Perini, K.; Lehti, S.; Lindén, T.; Luukka, P.; Mäenpää, T.; Peltola, T.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Ungaro, D.; Wendland, L.; Banzuzi, K.; Karjalainen, A.; Korpela, A.; Tuuva, T.; Besancon, M.; Choudhury, S.; Dejardin, M.; Denegri, D.; Fabbro, B.; Faure, J. L.; Ferri, F.; Ganjour, S.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Locci, E.; Malcles, J.; Millischer, L.; Nayak, A.; Rander, J.; Rosowsky, A.; Shreyber, I.; Titov, M.; Baffioni, S.; Beaudette, F.; Benhabib, L.; Bianchini, L.; Bluj, M.; Broutin, C.; Busson, P.; Charlot, C.; Daci, N.; Dahms, T.; Dobrzynski, L.; Granier de Cassagnac, R.; Haguenauer, M.; Miné, P.; Mironov, C.; Naranjo, I. N.; Nguyen, M.; Ochando, C.; Paganini, P.; Sabes, D.; Salerno, R.; Sirois, Y.; Veelken, C.; Zabi, A.; Agram, J.-L.; Andrea, J.; Bloch, D.; Bodin, D.; Brom, J.-M.; Cardaci, M.; Chabert, E. C.; Collard, C.; Conte, E.; Drouhin, F.; Ferro, C.; Fontaine, J.-C.; Gelé, D.; Goerlach, U.; Juillot, P.; Le Bihan, A.-C.; Van Hove, P.; Fassi, F.; Mercier, D.; Beauceron, S.; Beaupere, N.; Bondu, O.; Boudoul, G.; Chasserat, J.; Chierici, R.; Contardo, D.; Depasse, P.; El Mamouni, H.; Fay, J.; Gascon, S.; Gouzevitch, M.; Ille, B.; Kurca, T.; Lethuillier, M.; Mirabito, L.; Perries, S.; Sordini, V.; Tschudi, Y.; Verdier, P.; Viret, S.; Tsamalaidze, Z.; Anagnostou, G.; Beranek, S.; Edelhoff, M.; Feld, L.; Heracleous, N.; Hindrichs, O.; Jussen, R.; Klein, K.; Merz, J.; Ostapchuk, A.

    2013-01-01T23:59:59.000Z

    First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of ?sNN =2.76??TeV are presented. The amplitudes of the second Fourier component (v2) of the ?0 azimuthal distributions are extracted using an event-plane technique. The values of v2 are studied as a function of the neutral pion transverse momentum (pT) for different classes of collision centrality in the kinematic range 1.6T2(pT) are similar to previously reported ?0 azimuthal anisotropy results from ?sNN=200??GeV Au-Au collisions at RHIC, despite a factor of ?14 increase in the center-of-mass energy. In the momentum range 2.5T<5.0??GeV/c , the neutral pion anisotropies are found to be smaller than those observed by CMS for inclusive charged particles.

  1. CONSTRAINTS ON THE ORIGIN OF COSMIC RAYS ABOVE 10{sup 18} eV FROM LARGE-SCALE ANISOTROPY SEARCHES IN DATA OF THE PIERRE AUGER OBSERVATORY

    SciTech Connect (OSTI)

    Abreu, P.; Andringa, S. [LIP and Instituto Superior Tecnico, Technical University of Lisbon (Portugal); Aglietta, M. [Istituto di Fisica dello Spazio Interplanetario (INAF), Universita di Torino and Sezione INFN, Torino (Italy); Ahlers, M. [University of Wisconsin, Madison, WI (United States); Ahn, E. J. [Fermilab, Batavia, IL (United States); Albuquerque, I. F. M. [Universidade de Sao Paulo, Instituto de Fisica, Sao Paulo, SP (Brazil); Allard, D. [Laboratoire AstroParticule et Cosmologie (APC), Universite Paris 7, CNRS-IN2P3, Paris (France); Allekotte, I. [Centro Atomico Bariloche and Instituto Balseiro (CNEA-UNCuyo-CONICET), San Carlos de Bariloche (Argentina); Allen, J. [New York University, New York, NY (United States); Allison, P. [Ohio State University, Columbus, OH (United States); Almela, A. [Universidad Tecnologica Nacional - Facultad Regional Buenos Aires, Buenos Aires (Argentina); Castillo, J. Alvarez [Universidad Nacional Autonoma de Mexico, Mexico, D.F. (Mexico); Alvarez-Muniz, J. [Universidad de Santiago de Compostela (Spain); Alves Batista, R. [Universidade Estadual de Campinas, IFGW, Campinas, SP (Brazil); Ambrosio, M.; Aramo, C. [Universita di Napoli 'Federico II' and Sezione INFN, Napoli (Italy); Aminaei, A. [IMAPP, Radboud University Nijmegen (Netherlands); Anchordoqui, L. [University of Wisconsin, Milwaukee, WI (United States); Antici'c, T. [Rudjer Boskovi'c Institute, 10000 Zagreb (Croatia); Arganda, E. [IFLP, Universidad Nacional de La Plata and CONICET, La Plata (Argentina); Collaboration: Pierre Auger Collaboration; and others

    2013-01-01T23:59:59.000Z

    A thorough search for large-scale anisotropies in the distribution of arrival directions of cosmic rays detected above 10{sup 18} eV at the Pierre Auger Observatory is reported. For the first time, these large-scale anisotropy searches are performed as a function of both the right ascension and the declination and expressed in terms of dipole and quadrupole moments. Within the systematic uncertainties, no significant deviation from isotropy is revealed. Upper limits on dipole and quadrupole amplitudes are derived under the hypothesis that any cosmic ray anisotropy is dominated by such moments in this energy range. These upper limits provide constraints on the production of cosmic rays above 10{sup 18} eV, since they allow us to challenge an origin from stationary galactic sources densely distributed in the galactic disk and emitting predominantly light particles in all directions.

  2. Anisotropy and Spatial Variation of Relative Permeability and Lithologic Character of Tensleep Sandstone Reservoirs in the Bighorn and Wind River Basins, Wyoming

    SciTech Connect (OSTI)

    Dunn, Thomas L.

    1996-10-01T23:59:59.000Z

    This multidisciplinary study is designed to provide improvements in advanced reservoir characterization techniques. This goal is to be accomplished through: (1) an examination of the spatial variation and anisotropy of relative permeability in the Tensleep Sandstone reservoirs of Wyoming; (2) the placement of that variation and anisotropy into paleogeographic, depositional, and diagenetic frameworks; (3) the development of pore-system imagery techniques for the calculation of relative permeability; (4) reservoir simulations testing the impact of relative permeability anisotropy and spatial variation on Tensleep Sandstone reservoir enhanced oil recovery; and (5) a geochemical investigation of the spatial and dynamic alteration in sandstone reservoirs that is caused by rock-fluid interaction during CO{sub 2}-enhanced oil recovery processes.

  3. Damage Detection in Plate Structures using Guided Ultrasonic Waves

    E-Print Network [OSTI]

    Jarmer, Gregory James Sylvester

    Guided Wave Structural Health Monitoring. ” Ultrasonics 50 (to Structural Health Monitoring. ” Philosophicalfor Guided-wave Structural Health Monitoring. ” Structural

  4. OBSERVATION OF ANISOTROPY IN THE ARRIVAL DIRECTIONS OF GALACTIC COSMIC RAYS AT MULTIPLE ANGULAR SCALES WITH IceCube

    SciTech Connect (OSTI)

    Abbasi, R.; Aguilar, J. A.; Andeen, K.; Baker, M. [Department of Physics, University of Wisconsin, Madison, WI 53706 (United States); Abdou, Y. [Department of Physics and Astronomy, University of Gent, B-9000 Gent (Belgium); Abu-Zayyad, T. [Department of Physics, University of Wisconsin, River Falls, WI 54022 (United States); Adams, J. [Department of Physics and Astronomy, University of Canterbury, Private Bag 4800, Christchurch (New Zealand); Ahlers, M. [Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP (United Kingdom); Altmann, D. [III. Physikalisches Institut, RWTH Aachen University, D-52056 Aachen (Germany); Auffenberg, J.; Becker, K.-H. [Department of Physics, University of Wuppertal, D-42119 Wuppertal (Germany); Bai, X. [Bartol Research Institute and Department of Physics and Astronomy, University of Delaware, Newark, DE 19716 (United States); Barwick, S. W. [Department of Physics and Astronomy, University of California, Irvine, CA 92697 (United States); Bay, R. [Department of Physics, University of California, Berkeley, CA 94720 (United States); Alba, J. L. Bazo; Benabderrahmane, M. L. [DESY, D-15735 Zeuthen (Germany); Beattie, K. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Beatty, J. J. [Department of Physics and Center for Cosmology and Astro-Particle Physics, Ohio State University, Columbus, OH 43210 (United States); Bechet, S. [Universite Libre de Bruxelles, Science Faculty CP230, B-1050 Brussels (Belgium); Becker, J. K. [Fakultaet fuer Physik and Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany)

    2011-10-10T23:59:59.000Z

    Between 2009 May and 2010 May, the IceCube neutrino detector at the South Pole recorded 32 billion muons generated in air showers produced by cosmic rays with a median energy of 20 TeV. With a data set of this size, it is possible to probe the southern sky for per-mil anisotropy on all angular scales in the arrival direction distribution of cosmic rays. Applying a power spectrum analysis to the relative intensity map of the cosmic ray flux in the southern hemisphere, we show that the arrival direction distribution is not isotropic, but shows significant structure on several angular scales. In addition to previously reported large-scale structure in the form of a strong dipole and quadrupole, the data show small-scale structure on scales between 15{sup 0} and 30{sup 0}. The skymap exhibits several localized regions of significant excess and deficit in cosmic ray intensity. The relative intensity of the smaller-scale structures is about a factor of five weaker than that of the dipole and quadrupole structure. The most significant structure, an excess localized at (right ascension {alpha} = 122.{sup 0}4 and declination {delta} = -47.{sup 0}4), extends over at least 20{sup 0} in right ascension and has a post-trials significance of 5.3{sigma}. The origin of this anisotropy is still unknown.

  5. Power and spectral index anisotropy of the entire inertial range of turbulence in the fast solar wind

    E-Print Network [OSTI]

    Wicks, R T; Chen, C H K; Schekochihin, A A

    2010-01-01T23:59:59.000Z

    We measure the power and spectral index anisotropy of high speed solar wind turbulence from scales larger than the outer scale down to the ion gyroscale, thus covering the entire inertial range. We show that the power and spectral indices at the outer scale of turbulence are approximately isotropic. The turbulent cascade causes the power anisotropy at smaller scales manifested by anisotropic scalings of the spectrum: close to k^{-5/3} across and k^{-2} along the local magnetic field, consistent with a critically balanced Alfvenic turbulence. By using data at different radial distances from the Sun, we show that the width of the inertial range does not change with heliocentric distance and explain this by calculating the radial dependence of the ratio of the outer scale to the ion gyroscale. At the smallest scales of the inertial range, close to the ion gyroscale, we find an enhancement of power parallel to the magnetic field direction coincident with a decrease in the perpendicular power. This is most likely ...

  6. Free energies, vacancy concentrations and density distribution anisotropies in hard--sphere crystals: A combined density functional and simulation study

    E-Print Network [OSTI]

    M. Oettel; S. Goerig; A. Haertel; H. Loewen; M. Radu; T. Schilling

    2010-09-03T23:59:59.000Z

    We perform a comparative study of the free energies and the density distributions in hard sphere crystals using Monte Carlo simulations and density functional theory (employing Fundamental Measure functionals). Using a recently introduced technique (Schilling and Schmid, J. Chem. Phys 131, 231102 (2009)) we obtain crystal free energies to a high precision. The free energies from Fundamental Measure theory are in good agreement with the simulation results and demonstrate the applicability of these functionals to the treatment of other problems involving crystallization. The agreement between FMT and simulations on the level of the free energies is also reflected in the density distributions around single lattice sites. Overall, the peak widths and anisotropy signs for different lattice directions agree, however, it is found that Fundamental Measure theory gives slightly narrower peaks with more anisotropy than seen in the simulations. Among the three types of Fundamental Measure functionals studied, only the White Bear II functional (Hansen-Goos and Roth, J. Phys.: Condens. Matter 18, 8413 (2006)) exhibits sensible results for the equilibrium vacancy concentration and a physical behavior of the chemical potential in crystals constrained by a fixed vacancy concentration.

  7. Effects of toughness anisotropy and combined tension, torsion, and bending loads on fracture behavior of ferritic nuclear pipe

    SciTech Connect (OSTI)

    Mohan, R.; Marshall, C.; Ghadiali, N.; Wilkowski, G. [Battelle, Columbus, OH (United States)

    1997-04-01T23:59:59.000Z

    This paper summarizes work on angled through-wall-crack initiation and combined loading effects on ferritic nuclear pipe performed as part of the Nuclear Regulatory Commission`s research program entitled {open_quotes}Short Cracks In Piping an Piping Welds{close_quotes}. The reader is referred to Reference 1 for details of the experiments and analyses conducted as part of this program. The major impetus for this work stemmed from the observation that initially circumferentially oriented cracks in carbon steel pipes exhibited a high tendency to grow at a different angle when the cracked pipes were subjected to bending or bending plus pressure loads. This failure mode was little understood, and the effect of angled crack grown from an initially circumferential crack raised questions about how cracks in a piping system subjected to combined loading with torsional stresses would behave. There were three major efforts undertaken in this study. The first involved a literature review to assess the causes of toughness anisotropy in ferritic pipes and to develop strength and toughness data as a function of angle from the circumferential plane. The second effort was an attempt to develop a screening criterion based on toughness anisotropy and to compare this screening criterion with experimental pipe fracture data. The third and more significant effort involved finite element analyses to examine why cracks grow at an angle and what is the effect of combined loads with torsional stresses on a circumferentially cracked pipe. These three efforts are summarized.

  8. Construction of KP solitons from wave patterns

    E-Print Network [OSTI]

    Sarbarish Chakravarty; Yuji Kodama

    2013-09-10T23:59:59.000Z

    We often observe that waves on the surface of shallow water form complex web-like patterns. They are examples of nonlinear waves, and these patterns are generated by nonlinear interactions among several obliquely propagating waves. In this note, we discuss how to construct an exact soliton solution of the KP equation from such web-pattern of shallow water wave. This can be regarded as an "inverse problem" in the sense that by measuring certain metric data of the solitary waves in the given pattern, it is possible to construct an exact KP soliton solution which can describe the non-stationary dynamics of the pattern.

  9. Thermal Gravitational Waves from Primordial Black Holes

    E-Print Network [OSTI]

    C. Sivaram; Kenath Arun

    2010-05-19T23:59:59.000Z

    Thermal gravitational waves can be generated in various sources such as, in the cores of stars, white dwarfs and neutron stars due to the fermion collisions in the dense degenerate Fermi gas. Such high frequency thermal gravitational waves can also be produced during the collisions in a gamma ray burst or during the final stages of the evaporation of primordial black holes. Here we estimate the thermal gravitational waves from primordial black holes and estimate the integrated energy of the gravitational wave emission over the entire volume of the universe and over Hubble time. We also estimate the gravitational wave flux from gamma ray bursts and jets.

  10. Refractive gravitational waves and quantum fluctuations

    E-Print Network [OSTI]

    John W. Barrett

    2000-11-14T23:59:59.000Z

    Refractive gravitational waves are a generalisation of impulsive waves on a null hypersurface in which the metric is discontinuous but a weaker continuity condition for areas holds. A simple example of a plane wave is examined in detail and two arguments are given that this should be considered a solution of Einstein's vacuum field equations. The study of these waves is motivated by quantum gravity, where the refractive plane waves are considered as elementary quantum fluctuations and the `area geometry' of a null hypersurface plays a primary role.

  11. Matter Wave Radiation Leading to Matter Teleportation

    E-Print Network [OSTI]

    Yong-Yi Huang

    2015-02-12T23:59:59.000Z

    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.

  12. Ponderomotive Forces On Waves In Modulated Media

    SciTech Connect (OSTI)

    Dodin, I.Y; Fisch, Nathaniel

    2014-02-28T23:59:59.000Z

    Nonlinear interactions of waves via instantaneous cross-phase modulation can be cast in the same way as ponderomotive wave-particle interactions in high-frequency electromagnetic fi eld. The ponderomotive effect arises when rays of a probe wave scatter off perturbations of the underlying medium produced by a second, modulation wave, much like charged particles scatter off a quasiperiodic field. Parallels with the point-particle dynamics, which itself is generalized by this theory, lead to new methods of wave manipulation, including asymmetric barriers for light.

  13. Kinematic dynamo induced by helical waves

    E-Print Network [OSTI]

    Wei, Xing

    2014-01-01T23:59:59.000Z

    We investigate numerically the kinematic dynamo induced by the superposition of two helical waves in a periodic box as a simplified model to understand the dynamo action in astronomical bodies. The effects of magnetic Reynolds number, wavenumber and wave frequency on the dynamo action are studied. It is found that this helical-wave dynamo is a slow dynamo. There exists an optimal wavenumber for the dynamo growth rate. A lower wave frequency facilitates the dynamo action and the oscillations of magnetic energy emerge at some particular wave frequencies.

  14. Point-contact spectroscopy investigation of superconducting-gap anisotropy in the nickel borocarbide compound LuNi2B2C

    E-Print Network [OSTI]

    Bobrov, NL; Beloborod'ko, SI; Tyutrina, LV; Yanson, IK; Naugle, Donald G.; Rathnayaka, KDD.

    2005-01-01T23:59:59.000Z

    Point-contact spectroscopy investigation of superconducting-gap anisotropy in the nickel borocarbide compound LuNi2B2C N. L. Bobrov,1,2 S. I. Beloborod?ko,1 L. V. Tyutrina,1 I. K. Yanson,1,* D. G. Naugle,2 and K. D. D. Rathnayaka2 1B. I. Verkin...: 63.20.Kr, 72.10.Di, 73.40.Jn I. INTRODUCTION The goal of this study was to investigate the anisotropy of the energy gap in nickel borocarbide superconductors ReNi2B2C. The crystallographic structure of these com- pounds resembles to some extent...

  15. SOLAR CYCLE DEPENDENCE OF THE DIURNAL ANISOTROPY OF 0.6 TeV COSMIC-RAY INTENSITY OBSERVED WITH THE MATSUSHIRO UNDERGROUND MUON DETECTOR

    SciTech Connect (OSTI)

    Munakata, K.; Mizoguchi, Y.; Kato, C.; Yasue, S.; Mori, S. [Department of Physics, Shinshu University, Matsumoto 390-8621 (Japan); Takita, M. [Institute for Cosmic Ray Research, University of Tokyo, Kashiwa 277-8582 (Japan); Kota, J., E-mail: kmuna00@shinshu-u.ac.j [Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 87721 (United States)

    2010-04-01T23:59:59.000Z

    We analyze the temporal variation of the diurnal anisotropy of sub-TeV cosmic-ray intensity observed with the Matsushiro (Japan) underground muon detector over two full solar activity cycles in 1985-2008. We find an anisotropy component in the solar diurnal anisotropy superimposed on the Compton-Getting anisotropy due to Earth's orbital motion around the Sun. The phase of this additional anisotropy is almost constant at {approx}15:00 local solar time corresponding to the direction perpendicular to the average interplanetary magnetic field at Earth's orbit, while the amplitude varies between a maximum (0.043% +- 0.002%) and minimum ({approx}0.008% +- 0.002%) in a clear correlation with the solar activity. We find a significant time lag between the temporal variations of the amplitude and the sunspot number (SSN) and obtain the best correlation coefficient of +0.74 with the SSN delayed for 26 months. We suggest that this anisotropy might be interpreted in terms of the energy change due to the solar-wind-induced electric field expected for galactic cosmic rays (GCRs) crossing the wavy neutral sheet. The average amplitude of the sidereal diurnal variation over the entire period is 0.034% +- 0.003%, which is roughly one-third of the amplitude reported from air shower and deep-underground muon experiments monitoring multi-TeV GCR intensity suggesting a significant attenuation of the anisotropy due to the solar modulation. We find, on the other hand, only a weak positive correlation between the sidereal diurnal anisotropy and the solar activity cycle in which the amplitude in the 'active' solar activity epoch is about twice the amplitude in the 'quiet' solar activity epoch. This implies that only one-fourth of the total attenuation varies in correlation with the solar activity cycle and/or the solar magnetic cycle. We finally examine the temporal variation of the 'single-band valley depth' (SBVD) quoted by the Milagro experiment and, in contrast with recent Milagro's report, we find no steady increase in the Matsushiro observations in a seven-year period between 2000 and 2007. We suggest, therefore, that the steady increase of the SBVD reported by the Milagro experiment is not caused by the decreasing solar modulation in the declining phase of the 23rd solar activity cycle.

  16. Gravitational waves from perturbed stars

    E-Print Network [OSTI]

    Valeria Ferrari

    2011-05-09T23:59:59.000Z

    Non radial oscillations of neutron stars are associated with the emission of gravitational waves. The characteristic frequencies of these oscillations can be computed using the theory of stellar perturbations, and they are shown to carry detailed information on the internal structure of the emitting source. Moreover, they appear to be encoded in various radiative processes, as for instance in the tail of the giant flares of Soft Gamma Repeaters. Thus, their determination is central to the theory of stellar perturbation. A viable approach to the problem consists in formulating this theory as a problem of resonant scattering of gravitational waves incident on the potential barrier generated by the spacetime curvature. This approach discloses some unexpected correspondences between the theory of stellar perturbations and the theory of quantum mechanics, and allows us to predict new relativistic effects.

  17. Reconstruction of nonlinear wave propagation

    DOE Patents [OSTI]

    Fleischer, Jason W; Barsi, Christopher; Wan, Wenjie

    2013-04-23T23:59:59.000Z

    Disclosed are systems and methods for characterizing a nonlinear propagation environment by numerically propagating a measured output waveform resulting from a known input waveform. The numerical propagation reconstructs the input waveform, and in the process, the nonlinear environment is characterized. In certain embodiments, knowledge of the characterized nonlinear environment facilitates determination of an unknown input based on a measured output. Similarly, knowledge of the characterized nonlinear environment also facilitates formation of a desired output based on a configurable input. In both situations, the input thus characterized and the output thus obtained include features that would normally be lost in linear propagations. Such features can include evanescent waves and peripheral waves, such that an image thus obtained are inherently wide-angle, farfield form of microscopy.

  18. Millimeter-wave active probe

    DOE Patents [OSTI]

    Majidi-Ahy, Gholamreza (Sunnyvale, CA); Bloom, David M. (Portola Valley, CA)

    1991-01-01T23:59:59.000Z

    A millimeter-wave active probe for use in injecting signals with frequencies above 50GHz to millimeter-wave and ultrafast devices and integrated circuits including a substrate upon which a frequency multiplier consisting of filter sections and impedance matching sections are fabricated in uniplanar transmission line format. A coaxial input and uniplanar 50 ohm transmission line couple an approximately 20 GHz input signal to a low pass filter which rolls off at approximately 25 GHz. An input impedance matching section couples the energy from the low pass filter to a pair of matched, antiparallel beam lead diodes. These diodes generate odd-numberd harmonics which are coupled out of the diodes by an output impedance matching network and bandpass filter which suppresses the fundamental and third harmonics and selects the fifth harmonic for presentation at an output.

  19. Freak waves in white dwarfs and magnetars

    SciTech Connect (OSTI)

    Sabry, R. [Theoretical Physics Group, Physics Department, Faculty of Science, Damietta University, New Damietta 34517 (Egypt); Department of Physics, College of Science and Humanitarian Studies, Salman bin Abdulaziz University, Alkharj (Saudi Arabia); International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Moslem, W. M. [International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Department of Physics, Faculty of Science, Port Said University, Port Said (Egypt); Centre for Theoretical Physics, The British University in Egypt (BUE), El-Shorouk City, Cairo (Egypt); Shukla, P. K. [International Centre for Advanced Studies in Physical Sciences, Faculty of Physics and Astronomy, Ruhr University Bochum, D-44780 Bochum (Germany); Department of Mechanical and Aerospace Engineering and Center for Energy Research, University of California, San Diego, La Jolla, California 92093 (United States)

    2012-12-15T23:59:59.000Z

    We report properties of ion acoustic freak waves that propagate in a plasma composed of warm ions and ultrarelativistic electrons and positrons. The dynamics of the nonlinear freak waves is governed by the nonlinear Schroedinger equation. The possible region for the freak waves to exist is defined precisely for typical parameters of white dwarfs and magnetars corona. It is found that for low wave number, the nonlinear ion-acoustic wave packets are structurally stable in magnetars corona than in white dwarfs. However, for large wave numbers the situation is opposite. The critical wave number threshold (k{sub c}), which indicates where the modulational instability sets in, is defined for both applications. It is seen that near to k{sub c} the freak wave amplitude becomes high, but it decreases whenever we stepped away from k{sub c}. For the wave numbers close to k{sub c}, the increase of the unperturbed density ratio of positrons-to-electrons ({beta}) would lead to increase the freak wave amplitude, but for larger wave numbers the amplitude decreases with the increase of {beta}.

  20. The Nature of Running Penumbral Waves Revealed

    E-Print Network [OSTI]

    D. Shaun Bloomfield; Andreas Lagg; Sami K. Solanki

    2007-09-24T23:59:59.000Z

    We seek to clarify the nature of running penumbral (RP) waves: are they chromospheric trans-sunspot waves or a visual pattern of upward-propagating waves? Full Stokes spectropolarimetric time series of the photospheric Si I 10827 \\AA line and the chromospheric He I 10830 \\AA multiplet were inverted using a Milne-Eddington atmosphere. Spatial pixels were paired between the outer umbral/inner penumbral photosphere and the penumbral chromosphere using inclinations retrieved by the inversion and the dual-height pairings of line-of-sight velocity time series were studied for signatures of wave propagation using a Fourier phase difference analysis. The dispersion relation for radiatively cooling acoustic waves, modified to incorporate an inclined propagation direction, fits well the observed phase differences between the pairs of photospheric and chromospheric pixels. We have thus demonstrated that RP waves are in effect low-beta slow-mode waves propagating along the magnetic field.

  1. Corvino's construction using Brill waves

    E-Print Network [OSTI]

    Domenico Giulini; Gustav Holzegel

    2005-08-17T23:59:59.000Z

    For two-black-hole time-symmetric initial data we consider the Corvino construction of gluing an exact Schwarzschild end. We propose to do this by using Brill waves. We address the question of whether this method can be used to reduce the overall energy, which seems to relate to the question of whether it can reduce the amount of `spurious' gravitational radiation. We find a positive answer at first order in the inverse gluing radius.

  2. Sequentially pulsed traveling wave accelerator

    DOE Patents [OSTI]

    Caporaso, George J. (Livermore, CA); Nelson, Scott D. (Patterson, CA); Poole, Brian R. (Tracy, CA)

    2009-08-18T23:59:59.000Z

    A sequentially pulsed traveling wave compact accelerator having two or more pulse forming lines each with a switch for producing a short acceleration pulse along a short length of a beam tube, and a trigger mechanism for sequentially triggering the switches so that a traveling axial electric field is produced along the beam tube in synchronism with an axially traversing pulsed beam of charged particles to serially impart energy to the particle beam.

  3. Wave propagation in axion electrodynamics

    E-Print Network [OSTI]

    Yakov Itin

    2007-06-20T23:59:59.000Z

    In this paper, the axion contribution to the electromagnetic wave propagation is studied. First we show how the axion electrodynamics model can be embedded into a premetric formalism of Maxwell electrodynamics. In this formalism, the axion field is not an arbitrary added Chern-Simon term of the Lagrangian, but emerges in a natural way as an irreducible part of a general constitutive tensor.We show that in order to represent the axion contribution to the wave propagation it is necessary to go beyond the geometric approximation, which is usually used in the premetric formalism. We derive a covariant dispersion relation for the axion modified electrodynamics. The wave propagation in this model is studied for an axion field with timelike, spacelike and null derivative covectors. The birefringence effect emerges in all these classes as a signal of Lorentz violation. This effect is however completely different from the ordinary birefringence appearing in classical optics and in premetric electrodynamics. The axion field does not simple double the ordinary light cone structure. In fact, it modifies the global topological structure of light cones surfaces. In CFJ-electrodynamics, such a modification results in violation of causality. In addition, the optical metrics in axion electrodynamics are not pseudo-Riemannian. In fact, for all types of the axion field, they are even non-Finslerian.

  4. Topological Aspects of Wave Propagation

    E-Print Network [OSTI]

    Carlos Valero

    2014-06-13T23:59:59.000Z

    In the context of wave propagation on a manifold X, the characteristic functions are real valued functions on cotangent bundle of X that specify the allowable phase velocities of the waves. For certain classes of differential operators (e.g Maxwell's Equations) the associated characteristic functions have singularities. These singularities account for phenomena like conical refraction and the transformation of longitudinal waves into transversal ones (or viceversa). For a specific class of differential operators on surface, we prove that the singularities of the characteristic functions can be accounted from purely topological considerations. We also prove that there is a natural way to desingularsize the characteristic functions, and observe that this fact and Morse Theory establishes a specific connection between singularities and critical points of these functions. The relation between characteristic functions and differential operators is obtained through what is known as the symbol of the operator. We establish a connection between these symbols and holomorphic vector fields, which will provide us with symbols whose characteristic functions have interesting singularity sets.

  5. On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy Industry

    E-Print Network [OSTI]

    Victoria, University of

    On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy On the Use of Computational Models for Wave Climate Assessment in Support of the Wave Energy Industry Effective, economic extraction of ocean wave energy requires an intimate under- standing of the ocean wave

  6. SPECTROSCOPIC OBSERVATIONS OF A CORONAL MORETON WAVE

    SciTech Connect (OSTI)

    Harra, Louise K. [UCL-Mullard Space Science Laboratory, Holmbury St. Mary, Dorking, Surrey, RH5 6NT (United Kingdom); Sterling, Alphonse C. [Space Science Office, VP62, NASA Marshall Space Flight Center, Huntsville, AL 35812 (United States); Goemoery, Peter [Astronomical Institute, Slovak Academy of Sciences, SK-05960 Tatranska Lomnica (Slovakia); Veronig, Astrid, E-mail: lkh@mssl.ucl.ac.uk, E-mail: alphonse.sterling@nasa.gov, E-mail: gomory@astro.s, E-mail: astrid.veronig@uni-graz.at [Institute of Physics, University of Graz, Universitaetsplatz 5, A-8010 Graz (Austria)

    2011-08-10T23:59:59.000Z

    We observed a coronal wave (EIT wave) on 2011 February 16, using EUV imaging data from the Solar Dynamics Observatory/Atmospheric Imaging Assembly (AIA) and EUV spectral data from the Hinode/EUV Imaging Spectrometer (EIS). The wave accompanied an M1.6 flare that produced a surge and a coronal mass ejection (CME). EIS data of the wave show a prominent redshifted signature indicating line-of-sight velocities of {approx}20 km s{sup -1} or greater. Following the main redshifted wave front, there is a low-velocity period (and perhaps slightly blueshifted), followed by a second redshift somewhat weaker than the first; this progression may be due to oscillations of the EUV atmosphere set in motion by the initial wave front, although alternative explanations may be possible. Along the direction of the EIS slit the wave front's velocity was {approx}500 km s{sup -1}, consistent with its apparent propagation velocity projected against the solar disk as measured in the AIA images, and the second redshifted feature had propagation velocities between {approx}200 and 500 km s{sup -1}. These findings are consistent with the observed wave being generated by the outgoing CME, as in the scenario for the classic Moreton wave. This type of detailed spectral study of coronal waves has hitherto been a challenge, but is now possible due to the availability of concurrent AIA and EIS data.

  7. 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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over OurThe Iron SpinPrincetonUsing Maps1DOETHE FUTURE LOOKS

  8. Measurement of the Azimuthal Anisotropy of Neutral Pions in Pb-Pb Collisions at ?s(NN)=2.76??TeV

    E-Print Network [OSTI]

    Baringer, Philip S.; Bean, Alice; Benelli, Gabriele; Kenny, R. P. III; Murray, Michael J.; Noonan, Danny; Sanders, Stephen J.; Stringer, Robert W.; Tinti, Gemma; Wood, Jeffrey Scott; Zhukova, Victoria; Chatrchyan, S.; Khachatryan, V.; Sirunyan, A. M.; Tumasyan, A.; Adam, W.; Aguilo, E.; Bergauer, T.

    2013-01-22T23:59:59.000Z

    First measurements of the azimuthal anisotropy of neutral pions produced in Pb-Pb collisions at a center-of-mass energy of ?s(NN)=2.76??TeV are presented. The amplitudes of the second Fourier component (v(2)) of the ?(0) ...

  9. Correlation between topography and magnetic surface anisotropy in epitaxial Fe films on vicinal-to-(001) Au surfaces with different step orientation

    E-Print Network [OSTI]

    Demokritov, S.O.

    Correlation between topography and magnetic surface anisotropy in epitaxial Fe films on vicinal in this respect,2­5 the surface topography in these films is often very complex, characterized by surface these films on vicinal to (001) Au substrates one finds a rich variety in the surface topography. We have

  10. The syn-and post-collisional evolution of the Romanian Carpathian foredeep: New constraints from anisotropy of magnetic susceptibility and paleostress analyses

    E-Print Network [OSTI]

    Utrecht, Universiteit

    anisotropy of magnetic susceptibility and paleostress analyses Iuliana Vasiliev a,b, , Liviu Maenco b,c nappe pile, the lower plate, and the overlying sedimentary rocks, indicates that two factors of the soft, non-competent rocks where the poor preservation of traditional kinematic indicators (e.g., faults

  11. Top-down and bottom-up through-thickness current anisotropy in a bilayer YBa2Cu3O7-x film

    E-Print Network [OSTI]

    Institute of Physics. DOI: 10.1063/1.2767772 High temperature superconducting HTS materials and wires hold and the field orientation experienced by a YBCO wire are application de- pendent, underscoring the importance of the Jc anisotropy. In a typical solenoid of YBCO wire, wound with the plane of the wire parallel

  12. Proton chemical shift anisotropy measurements of hydrogen-bonded functional groups by fast magic-angle spinning solid-state NMR

    E-Print Network [OSTI]

    Proton chemical shift anisotropy measurements of hydrogen-bonded functional groups by fast magic) spectroscopy is one of the most suitable tools for studying hydrogen bonding phenomena. Proton NMR spectroscopy theoretically4 and experimentally5 that the isotropic chemical shifts of hydroxyl or amide protons depend

  13. Shape and strain-induced magnetization reorientation and magnetic anisotropy in thin film Ti/CoCrPt/Ti lines and rings

    E-Print Network [OSTI]

    Velazquez, D.

    The contributions to the magnetic anisotropy of thin-film rings and lines of width 50 nm and above made from Ti(5?nm)/Co[subscript 0.66]Cr[subscript 0.22]Pt[subscript 0.12] (10 and 20 nm)/Ti (3 nm) with a perpendicular ...

  14. Magnetic anisotropy in epitaxial CrO2 and CrO2/Cr2O3 bilayer thin films N. A. Frey, S. Srinath, and H. Srikanth*

    E-Print Network [OSTI]

    Pennycook, Steve

    3 as the system is cooled below the antiferromagnetic transition has been widely studied MINT Center, University of Alabama, Tuscaloosa, Alabama 35487, USA Received 7 January 2006; revised for the room temperature anisotropy constant scaled with the film thickness and the TS data is influenced

  15. Azimuthal anisotropy of charged particles at high transverse momenta in Pb-Pb collisions at ?s NN=2.76TeV

    E-Print Network [OSTI]

    Bauer, Gerry P.

    The azimuthal anisotropy of charged particles in Pb-Pb collisions at ?sNN=2.76??TeV is measured with the CMS detector at the LHC over an extended transverse momentum (pT) range up to approximately 60??GeV/c. The data cover ...

  16. Controllable strain-induced uniaxial anisotropy of Fe{sub 81}Ga{sub 19} films deposited on flexible bowed-substrates

    SciTech Connect (OSTI)

    Dai, Guohong [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); School of Science, Nanchang University, Nanchang 330031 (China); Zhan, Qingfeng, E-mail: zhanqf@nimte.ac.cn; Yang, Huali; Liu, Yiwei; Zhang, Xiaoshan; Zuo, Zhenghu; Chen, Bin; Li, Run-Wei, E-mail: runweili@nimte.ac.cn [Key Laboratory of Magnetic Materials and Devices, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China); Zhejiang Province Key Laboratory of Magnetic Materials and Application Technology, Ningbo Institute of Material Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201 (China)

    2013-11-07T23:59:59.000Z

    We propose a convenient method to induce a uniaxial anisotropy in magnetostrictive Fe{sub 81}Ga{sub 19} films grown on flexible polyethylene terephthalate (PET) substrates by bending the substrate prior to deposition. A tensile/compressive stress is induced in the Fe{sub 81}Ga{sub 19} films when PET substrates are shaped from concave/convex to flat after deposition. The stressed Fe{sub 81}Ga{sub 19} films exhibit a significant uniaxial magnetic anisotropy due to the internal stress arising from changes in shape of PET substrates. The easy axis is along the tensile stress direction and the coercive field along easy axis is increased with increasing the internal tensile stress. The remanence of hard axis is decreased with increasing the compressive stress, while the coercive field is almost unchanged. A modified Stoner-Wohlfarth model with considering the distribution of easy axes in polycrystalline films is used to account for the magnetic properties tuned by the strain-controlled magnetoelastic anisotropy in flexible Fe{sub 81}Ga{sub 19} films. Our investigations provide a convenient way to induce uniaxial magnetic anisotropy, which is particularly important for fabricating flexible magnetoelectronic devices.

  17. The Loudest Gravitational Wave Events

    E-Print Network [OSTI]

    Hsin-Yu Chen; Daniel E. Holz

    2014-09-04T23:59:59.000Z

    As first emphasized by Bernard Schutz, there exists a universal distribution of signal-to-noise ratios for gravitational wave detection. Because gravitational waves (GWs) are almost impossible to obscure via dust absorption or other astrophysical processes, the strength of the detected signal is dictated solely by the emission strength and the distance to the source. Assuming that the space density of an arbitrary population of GW sources does not evolve, we show explicitly that the distribution of detected signal-to-noise (SNR) values depends solely on the detection threshold; it is independent of the detector network (interferometer or pulsar timing array), the individual detector noise curves (initial or Advanced LIGO), the nature of the GW sources (compact binary coalescence, supernova, or some other discrete source), and the distributions of source variables (only non-spinning neutron stars of mass exactly $1.4\\,M_\\odot$ or a complicated distribution of masses and spins). We derive the SNR distribution for each individual detector within a network as a function of the relative detector orientations and sensitivities. While most detections will have SNR near the detection threshold, there will be a tail of events to higher SNR. We derive the SNR distribution of the loudest (highest SNR) events in any given sample of detections. We find that the median SNR of the loudest out of the first four events should have an $\\mbox{SNR}=22$ (for a threshold of 12, appropriate for the Advanced LIGO/Virgo network), increasing to a median value for the loudest SNR of 47 for 40 detections. We expect these loudest events to provide particularly powerful constraints on their source parameters, and they will play an important role in extracting astrophysics from gravitational wave sources. These distributions also offer an important internal calibration of the response of the GW detector networks.

  18. Particle acceleration in superluminal strong waves

    E-Print Network [OSTI]

    Teraki, Yuto; Nagataki, Shigehiro

    2015-01-01T23:59:59.000Z

    We calculate the electron acceleration in random superluminal strong waves (SLSWs) and radiation from them by using numerical methods in the context of the termination shock of the pulsar wind nebulae. We pursue the electrons by solving the equation of motion in the analytically expressed electromagnetic turbulences. These consist of primary SLSW and isotropically distributed secondary electromagnetic waves. Under the dominance of the secondary waves, all electrons gain nearly equal energy. On the other hand, when the primary wave is dominant, selective acceleration occurs. The phase of the primary wave felt by the electrons moving nearly along the wavevector changes very slowly compared to the oscillation of the wave, which is called "phase locked", and such electrons are continuously accelerated. This acceleration by SLSWs may play a crucial role in the pre-acceleration for the shock acceleration. In general, the radiation from the phase-locked population is different from the synchro-Compton radiation. How...

  19. Wave Heating of the Solar Atmosphere

    E-Print Network [OSTI]

    Arregui, I

    2015-01-01T23:59:59.000Z

    Magnetic waves are a relevant component in the dynamics of the solar atmosphere. Their significance has increased because of their potential as a remote diagnostic tool and their presumed contribution to plasma heating processes. We discuss our current understanding on coronal heating by magnetic waves, based on recent observational evidence and theoretical advances. The discussion starts with a selection of observational discoveries that have brought magnetic waves to the forefront of the coronal heating discussion. Then, our theoretical understanding on the nature and properties of the observed waves and the physical processes that have been proposed to explain observations are described. Particular attention is given to the sequence of processes that link observed wave characteristics with concealed energy transport, dissipation, and heat conversion. We conclude with a commentary on how the combination of theory and observations should help us understanding and quantifying magnetic wave heating of the sola...

  20. Refrigeration system having standing wave compressor

    DOE Patents [OSTI]

    Lucas, Timothy S. (Glen Allen, VA)

    1992-01-01T23:59:59.000Z

    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.