National Library of Energy BETA

Sample records for velocity wave probe

  1. wave velocity group velocity

    E-Print Network [OSTI]

    Walker, D. Greg

    -11 3.5e-11 4e-11 4.5e-11 5e-11 400 500 600 700 800 900 1000 location(nm) temperature(K) wave location 15 20 25 0 2 4 6 8 10 12 numberdensity(a.u.) frequency (THz) Summary Model Simulation Results Context. - Seitz and Koehler (1956) solve Boltzmann transport equations Monte Carlo approach is used to· 90 100 3e

  2. Three axis velocity probe system

    DOE Patents [OSTI]

    Fasching, George E. (Morgantown, WV); Smith, Jr., Nelson S. (Morgantown, WV); Utt, Carroll E. (Morgantown, WV)

    1992-01-01

    A three-axis velocity probe system for determining three-axis positional velocities of small particles in fluidized bed systems and similar applications. This system has a sensor head containing four closely-spaced sensing electrodes of small wires that have flat ends to establish a two axis plane, e.g. a X-Y plane. Two of the sensing electrodes are positioned along one of the axes and the other two are along the second axis. These four sensing electrodes are surrounded by a guard electrode, and the outer surface is a ground electrode and support member for the sensing head. The electrodes are excited by, for example, sinusoidal voltage having a peak-to-peak voltage of up to 500 volts at a frequency of 2 MHz. Capacitive currents flowing between the four sensing electrodes and the ground electrode are influenced by the presence and position of a particle passing the sensing head. Any changes in these currents due to the particle are amplified and synchronously detected to produce positional signal values that are converted to digital form. Using these digital forms and two values of time permit generation of values of the three components of the particle vector and thus the total velocity vector.

  3. 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

  4. Characterization of a Dipole Flow System Using Point Velocity Probes

    E-Print Network [OSTI]

    Bowen, Ian Reed

    2010-11-23

    A direct groundwater velocity measurement tool, the Point Velocity Probe, was developed to measure velocities in the vertical and horizontal directions. The tool was designed and tested in a low-cost laboratory flow-through tank. Following testing...

  5. Field comparison of the point velocity probe with other groundwater velocity measurement methods

    E-Print Network [OSTI]

    Labaky, W.; Devlin, John F.; Gillham, R. W.

    2009-03-14

    Field testing of a new tool for measuring groundwater velocities at the centimeter scale, the point velocity probe (PVP), was undertaken at Canadian Forces Base, Borden, Ontario, Canada. The measurements were performed in a sheet pile...

  6. Millimeter-wave active probe

    DOE Patents [OSTI]

    Majidi-Ahy, Gholamreza (Sunnyvale, CA); Bloom, David M. (Portola Valley, CA)

    1991-01-01

    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.

  7. Crust and Upper Mantle P Wave Velocity Structure Beneath Valles...

    Open Energy Info (EERE)

    Crust and Upper Mantle P Wave Velocity Structure Beneath Valles Caldera, New Mexico- Results from the Jemez Teleseismic Tomography Experiment Jump to: navigation, search OpenEI...

  8. Wavefield Analysis of Rayleigh Waves for Near-Surface Shear-Wave Velocity

    E-Print Network [OSTI]

    Zeng, Chong

    2011-05-18

    Shear (S)-wave velocity is a key property of near-surface materials and is the fundamental parameter for many environmental and engineering geophysical studies. Directly acquiring accurate S-wave velocities from a seismic shot gather is usually...

  9. Noninvasive electromechanical wave imaging and conduction velocity estimation in vivo

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    Noninvasive electromechanical wave imaging and conduction velocity estimation in vivo Elisa University, New York, NY, USA E-mail: ek2191@columbia.edu Abstract-- Electromechanical imaging is a novel identify and separate the electromechanical waves from the hemodynamically induced waves and determine

  10. Estimating propagation velocity through a surface acoustic wave sensor

    DOE Patents [OSTI]

    Xu, Wenyuan (Oakdale, MN); Huizinga, John S. (Dellwood, MN)

    2010-03-16

    Techniques are described for estimating the propagation velocity through a surface acoustic wave sensor. In particular, techniques which measure and exploit a proper segment of phase frequency response of the surface acoustic wave sensor are described for use as a basis of bacterial detection by the sensor. As described, use of velocity estimation based on a proper segment of phase frequency response has advantages over conventional techniques that use phase shift as the basis for detection.

  11. On electromagnetic waves with a negative group velocity

    SciTech Connect (OSTI)

    Makarov, V. P.; Rukhadze, A. A.; Samokhin, A. A. [Russian Academy of Sciences, Prokhorov Institute of General Physics (Russian Federation)

    2010-12-15

    Recent publications devoted to the electrodynamics of media in which waves with a negative group velocity can exist are discussed. The properties of such waves have been studied from the beginning of the past century, and the most important results in this field were obtained by Soviet physicists in the 1940s-1950s. However, in most recent publications, this circumstance has not been taken into account.

  12. Continuous subsurface velocity measurement with coda wave interferometry

    E-Print Network [OSTI]

    Niu, Fenglin

    . The experiment site is located 10 km west to the seismically very active Xiaojiang fault zone. An electric hammer was used as a source to generate highly repeatable seismic waves, which were recorded by 5 short is interpreted as the velocity response to the barometric pressure. A multivariate linear regression analysis

  13. Matter wave optical techniques for probing many-body targets

    E-Print Network [OSTI]

    Sanders, Scott Nicholas

    2010-01-01

    This thesis reports on our investigation of the uses of matter waves to probe many-body targets. We begin by discussing decoherence in an atom interferometer, in which a free gas acts as a refractive medium for a matter ...

  14. Photospheric Logarithmic Velocity Spirals as MHD Wave Generation Mechanisms

    E-Print Network [OSTI]

    Mumford, S J

    2015-01-01

    High-resolution observations of the solar photosphere have identified a wide variety of spiralling motions in the plasma. These spirals vary in properties, but are observed to be abundant on the solar surface. In this work these spirals are studied for their potential as magnetohydrodynamic (MHD) wave generation mechanisms. The inter-granular lanes, where these spirals are commonly observed, are also regions where the magnetic field strength is higher than average. This combination of magnetic field and spiralling plasma is a recipe for the generation of Alfv\\'en waves and other MHD waves. This work employs numerical simulations of a self-similar magnetic flux tube embedded in a realistic, gravitationally stratified, solar atmosphere to study the effects of a single magnetic flux tube perturbed by a logarithmic velocity spiral driver. The expansion factor of the logarithmic spiral driver is varied, multiple simulations are run for a range of values of the expansion factor centred around observational data. Th...

  15. Stress-wave velocity of wood-based panels: Effect of moisture,

    E-Print Network [OSTI]

    Stress-wave velocity of wood-based panels: Effect of moisture, product type, and material direction Guangping Han Qinglin Wu Xiping Wang Abstract The effect of moisture on longitudinal stress-wave veloc- ity, particleboard, and southern pine lumber was evaluated. It was shown that the stress-wave velocity decreased

  16. Warm wave breaking of nonlinear plasma waves with arbitrary phase velocities C. B. Schroeder, E. Esarey, and B. A. Shadwick

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    conventional technology nonlinear plasma waves driven by intense laser pulses. A basic quantity of interest, hence, the above expres- sion for Eth does not apply. Low-energy particle beam-driven plasma waves alsoWarm wave breaking of nonlinear plasma waves with arbitrary phase velocities C. B. Schroeder, E

  17. Anomalous shear wave delays and surface wave velocities at Yellowstone Caldera, Wyoming

    SciTech Connect (OSTI)

    Daniel, R.G.; Boore, D.M.

    1982-04-10

    To investigate the effects of a geothermal area on the propagation of intermediate-period (1--30 s) teleseismic body waves and surface waves, a specially designed portable seismograph system was operated in Yellowstone Caldera, Wyoming. Travel time residuals, relative to a station outside the caldera, of up to 2 s for compressional phases are in agreement with short-period residuals for P phases measured by other investigators. Travel time delays for shear arrivals in the intermediate-period band range from 2 to 9 s and decrease with increasing dT/d..delta... Measured Rayleigh wave phase velocities are extremely low, ranging from 3.2 km/s at 27-s period to 2.0 km/s at 7-s period; the estimated uncertainty associated with these values is 15%. We propose a model for compressional and shear velocities and Poisson's ratio beneath the Yellowstone caldera which fits the teleseismic body and surface wave data: it consists of a highly anomalous crust with an average shear velocity of 3.0 km/s overlying an upper mantle with average velocity of 4.1 km/s. The high average value of Poisson's ratio in the crust (0.34) suggests the presence of fluids there; Poisson's ratio in the mantle between 40 and approximately 200 km is more nearly normal (0.29) than in the crust. A discrepancy between normal values of Poisson's ratio in the crust calculated from short-period data and high values calculated from teleseismic data can be resolved by postulating a viscoelastic crustal model with frequency-dependent shear velocity and attenuation.

  18. Variation of seismic-wave velocities in westerly granite under stress 

    E-Print Network [OSTI]

    Al-Shaibani, Abdulaziz Muhareb

    1994-01-01

    Seismic-wave velocities in cracked rocks increase with stress. It is believed that, within less than half the rupture pressure, this velocity increase occurs due to the closure of cracks. Previous studies have shown that, ...

  19. A study of vacuum arc ion velocities using a linear set of probes

    SciTech Connect (OSTI)

    Hohenbild, Stefan; Grubel, Christoph; Yushkov, Georgy Yu.; Oks, Efim M.; Anders, Andre

    2008-07-15

    The most likely velocity of ions moving away from vacuum arc cathode spots was measured using a set of probes along the path of plasma expansion. The goal was to determine how much, if any, change of the ion drift velocity occurs in the expanded plasma. The arc discharge current was perturbed to create plasma density markers whose travel is picked up by the set of probes. It was found that the perturbation with current oscillations did not result in consistent data because ion current maxima and minima are not only determined by the plasma production but by the transients of the arc pulse and by the asymmetry of the ion velocity distribution function. Perturbation with a short current spike was more conclusive. The ion velocity was measured to be slightly reduced with increasing distance from the cathode, which can be explained by collisions of ions with the background of neutrals. The ion velocity was increased when the arc current was increased, which correlated with enhanced arc voltage and power dissipation. The ion velocity could be enhanced when the plasma was produced in a non-uniform magnetic field.

  20. Three-dimensional P and S waves velocity structures of the Coso...

    Open Energy Info (EERE)

    Three-dimensional P and S waves velocity structures of the Coso geothermal area, California, from microseismic travel time data Jump to: navigation, search OpenEI Reference...

  1. Near-Surface Shear-Wave Velocity Measurements in Unlithified Sediment

    E-Print Network [OSTI]

    Rickards, Benjamin Thomas

    2011-05-31

    Shear-wave (S-wave) velocity can be directly correlated to material stiff¬ness making it a valuable physical property that has found uses in construction, engineering, and envi-ronmental projects. This study compares three ...

  2. Surface acoustic wave probe implant for predicting epileptic seizures

    DOE Patents [OSTI]

    Gopalsami, Nachappa (Naperville, IL); Kulikov, Stanislav (Sarov, RU); Osorio, Ivan (Leawood, KS); Raptis, Apostolos C. (Downers Grove, IL)

    2012-04-24

    A system and method for predicting and avoiding a seizure in a patient. The system and method includes use of an implanted surface acoustic wave probe and coupled RF antenna to monitor temperature of the patient's brain, critical changes in the temperature characteristic of a precursor to the seizure. The system can activate an implanted cooling unit which can avoid or minimize a seizure in the patient.

  3. Nondestructive millimeter wave imaging and spectroscopy using dielectric focusing probes

    SciTech Connect (OSTI)

    Hejase, Jose A.; Shane, Steven S.; Park, Kyoung Y.; Chahal, Premjeet [Terahertz Systems Laboratory (TeSLa) - Department of Electrical and Computer Engineering, Michigan State University, East Lansing, MI 48823 (United States)

    2014-02-18

    A tool for interrogating objects over a wide band of frequencies with subwavelength resolution at small standoff distances (near field region) in the transmission mode using a single source and detector measurement setup in the millimeter wave band is presented. The design utilizes optics like principles for guiding electromagnetic millimeter waves from large cross-sectional areas to considerably smaller sub-wavelength areas. While plano-convex lenses can be used to focus waves to a fine resolution, they usually require a large stand-off distance thus resulting in alignment and spacing issues. The design procedure and simulation analysis of the focusing probes are presented in this study along with experimental verification of performance and imaging and spectroscopy examples. Nondestructive evaluation will find benefit from such an apparatus including biological tissue imaging, electronic package integrity testing, composite dielectric structure evaluation for defects and microfluidic sensing.

  4. The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission

    E-Print Network [OSTI]

    Wygant, J. R.

    The Electric Fields and Waves (EFW) Instruments on the two Radiation Belt Storm Probe (RBSP) spacecraft (recently renamed the Van Allen Probes) are designed to measure three dimensional quasi-static and low frequency ...

  5. Argon–oxygen dc magnetron discharge plasma probed with ion acoustic waves

    SciTech Connect (OSTI)

    Saikia, Partha, E-mail: partha.008@gmail.com; Saikia, Bipul Kumar; Goswami, Kalyan Sindhu [Centre of Plasma Physics, Institute for Plasma Research, Nazirakhat, Sonapur, Kamrup, Assam 782 402 (India); Phukan, Arindam [Madhabdev College, Narayanpur, Lakhimpur, Assam 784164 (India)

    2014-05-15

    The precise determination of the relative concentration of negative ions is very important for the optimization of magnetron sputtering processes, especially for those undertaken in a multicomponent background produced by adding electronegative gases, such as oxygen, to the discharge. The temporal behavior of an ion acoustic wave excited from a stainless steel grid inside the plasma chamber is used to determine the relative negative ion concentration in the magnetron discharge plasma. The phase velocity of the ion acoustic wave in the presence of negative ions is found to be faster than in a pure argon plasma, and the phase velocity increases with the oxygen partial pressure. Optical emission spectroscopy further confirms the increase in the oxygen negative ion density, along with a decrease in the argon positive ion density under the same discharge conditions. The relative negative ion concentration values measured by ion acoustic waves are compared with those measured by a single Langmuir probe, and a similarity in the results obtained by both techniques is observed.

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

    SciTech Connect (OSTI)

    Jun, Hyun-Su Lee, Yun-Seong

    2014-02-15

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

  7. In-situ, high-frequency P-Wave velocity measurements within 1 m of the Earth’s surface

    E-Print Network [OSTI]

    Baker, Gregory S.; Steeples, Don W.; Schmeissner, Chris M.

    1999-03-01

    Seismic P-wave velocities in near?surface materials can be much slower than the speed of sound waves in air (normally 335 m/s or 1100 ft/s). Difficulties often arise when measuring these low?velocity P-waves because of interference by the air wave...

  8. Wave-induced velocities inside a model seagrass bed

    E-Print Network [OSTI]

    Luhar, Mitul

    Laboratory measurements reveal the flow structure within and above a model seagrass meadow (dynamically similar to Zostera marina) forced by progressive waves. Despite being driven by purely oscillatory flow, a mean current ...

  9. Noninvasive electromechanical wave imaging and conduction-relevant velocity estimation in vivo

    E-Print Network [OSTI]

    Konofagou, Elisa E.

    Noninvasive electromechanical wave imaging and conduction-relevant velocity estimation in vivo-correlation Displacement Electromechanical Left ventricle Myocardial Pacing a b s t r a c t Electromechanical wave imaging-type mice (n = 12) at high frame rates in order to take advantage of the transient electromechanical

  10. Wave Packet for Massless Fermions and its Implication to the Superluminal Velocity Statistics of Neutrino

    E-Print Network [OSTI]

    Kelin Wang; Zexian Cao

    2012-01-06

    Non-dispersive wave packet for massless fermions is formulated on the basis of squeezed coherent states that are put in a form of common eigenfunction for the Hamiltonian and the helicity operator, starting from the Dirac equation. The wave packet thus constructed is demonstrated to propagate at a constant velocity as that of light. This explicit expression of wave packet for the massless fermions can facilitate theoretical analysis of problems where a wave packet is of formal significance. Furthermore, extensive wave packet may result in a superluminal velocity statistics if determined from the time-of-flight measurement, as recently done on muon neutrinos, when a threshold particle flux or energy transfer, which is eventually referred to the propagation of wave packet, to invoke a detection event is assumed.

  11. Extensional wave attenuation and velocity in partially-saturated sand in the sonic frequency range

    SciTech Connect (OSTI)

    Liu, Z.; Rector, J.W.; Nihei, K.T.; Tomutsa, L.; Myer, L.R.; Nakagawa, S.

    2002-06-17

    Extensional wave attenuation and velocity measurements on a high permeability Monterey sand were performed over a range of gas saturations for imbibition and degassing conditions. These measurements were conducted using extensional wave pulse propagation and resonance over a 1 - 9 kHz frequency range for a hydrostatic confining pressure of 8.3 MPa. Analysis of the extensional wave data and the corresponding X-ray CT images of the gas saturation show strong attenuation resulting from the presence of the gas (QE dropped from 300 for the dry sand to 30 for the partially-saturated sand), with larger attenuation at a given saturation resulting from heterogeneous gas distributions. The extensional wave velocities are in agreement with Gassmann theory for the test with near-homogeneous gas saturation and with a patchy saturation model for the test with heterogeneous gas saturation. These results show that partially-saturated sands under moderate confining pressure can produce strong intrinsic attenuation for extensional waves.

  12. Excitation of solitons by an external resonant wave with a slowly varying phase velocity

    SciTech Connect (OSTI)

    Aranson, I.; Meerson, B. [Hebrew Univ., Jerusalem (Israel). Racah Inst. of Physics; Tajima, Toshiki [Texas Univ., Austin, TX (United States)

    1992-02-01

    A novel mechanism is proposed for the excitation of solitons in nonlinear dispersive media. The mechanism employs an external pumping wave with a varying phase velocity, which provides a continuous resonant excitation of a nonlinear wave in the medium. Two different schemes of a continuous resonant growth (continuous phase-locking) of the induced nonlinear wave are suggested. The first of them requires a definite time dependence of the pumping wave phase velocity and is relatively sensitive to the initial wave phase. The second employs the dynamic autoresonance effect and is insensitive to the exact time dependence of the pumping wave phase velocity. It is demonstrated analytically and numerically, for a particular example of a driven Korteweg-de Vries (KdV) equation with periodic boundary conditions, that as the nonlinear wave grows, it transforms into a soliton, which continues growing and accelerating adiabatically. A fully nonlinear perturbation theory is developed for the driven KdV equation to follow the growing wave into the strongly nonlinear regime and describe the soliton formation.

  13. Probe Spin-Velocity Dependent New Interactions by Spin Relaxation Times of Polarized $^{3}He$ Gas

    E-Print Network [OSTI]

    H. Yan; G. A. Sun; S. M. Peng; Y. Zhang; C. B. Fu; Hao Guo; B. Q. Liu

    2015-09-18

    We have constrained possible new interactions which produce nonrelativistic potentials between polarized neutrons and unpolarized matter proportional to $\\alpha\\vec{\\sigma}\\cdot\\vec{v}$ where $\\vec{\\sigma}$ is the neutron spin and $\\vec{v}$ is the relative velocity. We use existing data from laboratory measurements on the very long $T_{1}$ and $T_{2}$ spin relaxation times of polarized $^{3}$He gas in glass cells.Using the best available measured $T_{2}$ of polarized $^{3}$He gas atoms as the polarized source and the earth as an unpolarized source, we obtain constraints on two new interactions. We present a new experimental upper bound on possible vector-axial-vector($V_{VA}$) type interactions for ranges between $1\\sim10^{8}$m. In combination with previous results, we set the most stringent experiment limits on $g_{V}g_{A}$ ranging from $\\sim\\mu$m to $\\sim10^{8}$m. We also report what is to our knowledge the first experimental upper limit on the possible torsion fields induced by the earth on its surface. Dedicated experiments could further improve these bounds by a factor of $\\sim100$. Our method of analysis also makes it possible to probe many velocity dependent interactions which depend on the spins of both neutrons and other particles which have never been searched for before experimentally.

  14. Minimal position-velocity uncertainty wave packets in relativistic and non-relativistic quantum mechanics

    SciTech Connect (OSTI)

    Al-Hashimi, M.H. Wiese, U.-J.

    2009-12-15

    We consider wave packets of free particles with a general energy-momentum dispersion relation E(p). The spreading of the wave packet is determined by the velocity v={partial_derivative}{sub p}E. The position-velocity uncertainty relation {delta}x{delta}v{>=}1/2 |<{partial_derivative}{sub p}{sup 2}E>| is saturated by minimal uncertainty wave packets {phi}(p)=Aexp(-{alpha}E(p)+{beta}p). In addition to the standard minimal Gaussian wave packets corresponding to the non-relativistic dispersion relation E(p)=p{sup 2}/2m, analytic calculations are presented for the spreading of wave packets with minimal position-velocity uncertainty product for the lattice dispersion relation E(p)=-cos(pa)/ma{sup 2} as well as for the relativistic dispersion relation E(p)={radical}(p{sup 2}+m{sup 2}). The boost properties of moving relativistic wave packets as well as the propagation of wave packets in an expanding Universe are also discussed.

  15. The occurrence and wave properties of H?-, He?-, and O?-band EMIC waves observed by the Van Allen Probes

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

    Saikin, A. A.; Zhang, J. -C.; Allen, R. C.; Smith, C. W.; Kistler, L. M.; Spence, H. E.; Torbert, R. B.; Kletzing, C. A.; Jordanova, Vania K.

    2015-09-26

    We perform a statistical study of electromagnetic ion cyclotron (EMIC) waves detected by the Van Allen Probes mission to investigate the spatial distribution of their occurrence, wave power, ellipticity, and normal angle. The Van Allen Probes have been used which allow us to explore the inner magnetosphere (1.1 to 5.8 RE). Magnetic field measurements from the Electric and Magnetic Field Instrument Suite and Integrated Science on board the Van Allen Probes are used to identify EMIC wave events for the first 22 months of the mission operation (8 September 2012 to 30 June 2014). EMIC waves are examined in H?-,more »He?-, and O?-bands. Over 700 EMIC wave events have been identified over the three different wave bands (265 H?-band events, 438 He?-band events, and 68 O?-band events). EMIC wave events are observed between L = 2 – 8, with over 140 EMIC wave events observed below L = 4. The results show that H?-band EMIC waves have two peak magnetic local time (MLT) occurrence regions: pre-noon (09:00 0.1 nT²/Hz), especially in the afternoon sector. Ellipticity observations reveal that linearly polarized EMIC waves dominate in lower L shells.« less

  16. Non-Gaussian properties of second-order wave orbital velocity

    E-Print Network [OSTI]

    Alberello, Alberto; Gramstad, Odin; Babanin, Alexander V; Toffoli, Alessandro

    2015-01-01

    A stochastic second-order wave model is applied to assess the statistical properties of wave orbital velocity in random sea states below the water surface. Directional spreading effects as well as the dependency of the water depth are investigated by means of a Monte-Carlo approach. Unlike for the surface elevation, sub-harmonics dominate the second-order contribution to orbital velocity. We show that a notable set-down occurs for the most energetic and steepest groups. This engenders a negative skewness in the temporal evolution of the orbital velocity. A substantial deviation of the upper and lower tails of the probability density function from the Gaussian distribution is noticed, velocities are faster below the wave trough and slower below the wave crest when compared with linear theory predictions. Second-order nonlinearity effects strengthen with reducing the water depth, while weaken with the broadening of the wave spectrum. The results are confirmed by laboratory data. Corresponding experiments have b...

  17. The occurrence and wave properties of H?-, He?-, and O?-band EMIC waves observed by the Van Allen Probes

    SciTech Connect (OSTI)

    Saikin, A. A.; Zhang, J. -C.; Allen, R. C.; Smith, C. W.; Kistler, L. M.; Spence, H. E.; Torbert, R. B.; Kletzing, C. A.; Jordanova, Vania K.

    2015-09-26

    We perform a statistical study of electromagnetic ion cyclotron (EMIC) waves detected by the Van Allen Probes mission to investigate the spatial distribution of their occurrence, wave power, ellipticity, and normal angle. The Van Allen Probes have been used which allow us to explore the inner magnetosphere (1.1 to 5.8 RE). Magnetic field measurements from the Electric and Magnetic Field Instrument Suite and Integrated Science on board the Van Allen Probes are used to identify EMIC wave events for the first 22 months of the mission operation (8 September 2012 to 30 June 2014). EMIC waves are examined in H?-, He?-, and O?-bands. Over 700 EMIC wave events have been identified over the three different wave bands (265 H?-band events, 438 He?-band events, and 68 O?-band events). EMIC wave events are observed between L = 2 – 8, with over 140 EMIC wave events observed below L = 4. The results show that H?-band EMIC waves have two peak magnetic local time (MLT) occurrence regions: pre-noon (09:00 < MLT ? 12:00) and afternoon (15:00 < MLT ? 17:00) sectors. He?-band EMIC waves feature an overall stronger dayside occurrence. O?-band EMIC waves have one peak region located in the morning sector at lower L shells (L < 4). He?-band EMIC waves average the highest wave power overall (>0.1 nT²/Hz), especially in the afternoon sector. Ellipticity observations reveal that linearly polarized EMIC waves dominate in lower L shells.

  18. Control of the chaotic velocity dispersion of a cold electron beam interacting with electrostatic waves

    E-Print Network [OSTI]

    Guido Ciraolo; Cristel Chandre; Ricardo Lima; Marco Pettini; Michel Vittot

    2006-07-31

    In this article we present an application of a method of control of Hamiltonian systems to the chaotic velocity diffusion of a cold electron beam interacting with electrostatic waves. We numerically show the efficiency and robustness of the additional small control term in restoring kinetic coherence of the injected electron beam.

  19. Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia)

    E-Print Network [OSTI]

    Snieder, Roel

    Increase of shear wave velocity before the 1998 eruption of Merapi volcano (Indonesia) U. Wegler,1 of the edifice of Merapi volcano (Java, Indonesia) before its eruption in 1998 by analyzing multiply scattered eruption of Merapi volcano (Indonesia), Geophys. Res. Lett., 33, L09303, doi:10.1029/2006GL025928. 1

  20. perovskite phase suggests slow longitudinal elastic-wave velocities propagating along the

    E-Print Network [OSTI]

    Hansell, Dennis

    perovskite phase suggests slow longitudinal elastic-wave velocities propagating along the [010] direction. In addition, it is also inferred that the post-perovskite phase forms a platy crystal habit) observed in the D region (1, 2) is possibly caused by the preferred orientation of the post-perovskite

  1. Developing regionalized models of lithospheric thickness and velocity structure across Eurasia and the Middle East from jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities

    SciTech Connect (OSTI)

    Julia, J; Nyblade, A; Hansen, S; Rodgers, A; Matzel, E

    2009-07-06

    In this project, we are developing models of lithospheric structure for a wide variety of tectonic regions throughout Eurasia and the Middle East by regionalizing 1D velocity models obtained by jointly inverting P-wave and S-wave receiver functions with Rayleigh wave group and phase velocities. We expect the regionalized velocity models will improve our ability to predict travel-times for local and regional phases, such as Pg, Pn, Sn and Lg, as well as travel-times for body-waves at upper mantle triplication distances in both seismic and aseismic regions of Eurasia and the Middle East. We anticipate the models will help inform and strengthen ongoing and future efforts within the NNSA labs to develop 3D velocity models for Eurasia and the Middle East, and will assist in obtaining model-based predictions where no empirical data are available and for improving locations from sparse networks using kriging. The codes needed to conduct the joint inversion of P-wave receiver functions (PRFs), S-wave receiver functions (SRFs), and dispersion velocities have already been assembled as part of ongoing research on lithospheric structure in Africa. The methodology has been tested with synthetic 'data' and case studies have been investigated with data collected at an open broadband stations in South Africa. PRFs constrain the size and S-P travel-time of seismic discontinuities in the crust and uppermost mantle, SRFs constrain the size and P-S travel-time of the lithosphere-asthenosphere boundary, and dispersion velocities constrain average S-wave velocity within frequency-dependent depth-ranges. Preliminary results show that the combination yields integrated 1D velocity models local to the recording station, where the discontinuities constrained by the receiver functions are superimposed to a background velocity model constrained by the dispersion velocities. In our first year of this project we will (i) generate 1D velocity models for open broadband seismic stations in the western half of the study area (Eurasia and the Middle East) and (ii) identify well located seismic events with event-station paths isolated to individual tectonic provinces within the study area and collect broadband waveforms and source parameters for the selected events. The 1D models obtained from the joint inversion will then be combined with published geologic terrain maps to produce regionalized models for distinctive tectonic areas within the study area, and the models will be validated through full waveform modeling of well-located seismic events recorded at local and regional distances.

  2. The relation between seismic P- and S-wave velocity dispersion in saturated rocks

    SciTech Connect (OSTI)

    Mavko, G. [Stanford Univ., CA (United States). Dept. of Geophysics] [Stanford Univ., CA (United States). Dept. of Geophysics; Jizba, D. [CSTJF, Pau (France)] [CSTJF, Pau (France)

    1994-01-01

    Seismic velocity dispersion in fluid-saturated rocks appears to be dominated by two mechanisms: the large scale mechanism modeled by Biot, and the local flow or squirt mechanism. The two mechanisms can be distinguished by the ratio of P- to S-wave dispersions, or more conveniently, by the ratio of dynamic bulk to shear compliance dispersions derived from the wave velocities. The authors` formulation suggests that when local flow dominates, the dispersion of the shear compliance will be approximately 4/15 the dispersion of the compressibility. When the Biot mechanism dominates, the constant of proportionality is much smaller. Their examination of ultrasonic velocities from 40 sandstones and granites shows that most, but not all, of the samples were dominated by local flow dispersion, particularly at effective pressures below 40 MPa.

  3. Three-dimensional crustal S wave velocity structure in Japan using microseismic data recorded by Hi-net

    E-Print Network [OSTI]

    Kawakatsu, Hitoshi

    Three-dimensional crustal S wave velocity structure in Japan using microseismic data recorded by Hi seismic noise. We applied this method to the recording of Hi-net tiltmeters in Japan at 679 stations from), Three-dimensional crustal S wave velocity structure in Japan using microseismic data recorded by Hi

  4. P-wave velocity structure of the crust and uppermost mantle beneath Iceland from local earthquake tomography

    E-Print Network [OSTI]

    Shen, Yang

    P-wave velocity structure of the crust and uppermost mantle beneath Iceland from local earthquake and uppermost mantle beneath Iceland, the keys to understanding the magma plumbing system of the hotspot develop a three-dimensional P-wave velocity model of the Icelandic crust and uppermost mantle from

  5. Extensional wave attenuation and velocity in partially saturated sand in the sonic frequency range

    SciTech Connect (OSTI)

    Liu, Z.; Rector, J.W.; Nihei, K.T.; Tomutsa, L.; Myer, L.R.; Nakagawa, S.

    2001-08-10

    Extensional wave attenuation and velocity measurements on a high permeability Monterey sand were performed over a range of gas saturations for imbibition and degassing conditions. These measurements were conducted using extensional wave pulse propagation and resonance over a 1-9 kHz frequency range for a hydrostatic confining pressure of 8.3 MPa. Analysis of the extensional wave data and the corresponding X-ray CT images of the gas saturation show strong attenuation resulting from the presence of the gas (Q{sub E} dropped from 300 for the dry sand to 30 for the partially-saturated sand), with larger attenuation at a given saturation resulting from heterogeneous gas distributions. The extensional wave velocities are in agreement with Gassmann theory for the test with near-homogeneous gas saturation and with a patchy saturation model for the test with heterogeneous gas saturation. These results show that partially-saturated sands under moderate confining pressure can produce strong intrinsic attenuation for extensional waves.

  6. Piezooptic Coefficients and Acoustic Wave Velocities in Sn2P2S6 Crystals

    E-Print Network [OSTI]

    O. Mys; I. Martynyuk-Lototska; A. Grabar; Yu. Vysochanskii; R. Vlokh

    2007-06-28

    Piezooptic coefficients of Sn2P2S6 crystals are experimentally determined for l=623.8 nm and T=293 K with the aid of interferometric technique. The components of the elastic stiffness tensor for these crystals are calculated on the basis of studies for the acoustic wave velocities. It is shown that acoustooptic figure of merit can achieve extremely high values for Sn2P2S6 crystals (M2 - 2x10-12s3/kg2).

  7. Standard practice for measuring the ultrasonic velocity in polyethylene tank walls using lateral longitudinal (LCR) waves

    E-Print Network [OSTI]

    American Society for Testing and Materials. Philadelphia

    2011-01-01

    1.1 This practice covers a procedure for measuring the ultrasonic velocities in the outer wall of polyethylene storage tanks. An angle beam lateral longitudinal (LCR) wave is excited with wedges along a circumferential chord of the tank wall. A digital ultrasonic flaw detector is used with sending-receiving search units in through transmission mode. The observed velocity is temperature corrected and compared to the expected velocity for a new, unexposed sample of material which is the same as the material being evaluated. The difference between the observed and temperature corrected velocities determines the degree of UV exposure of the tank. 1.2 The practice is intended for application to the outer surfaces of the wall of polyethylene tanks. Degradation typically occurs in an outer layer approximately 3.2-mm (0.125-in.) thick. Since the technique does not interrogate the inside wall of the tank, wall thickness is not a consideration other than to be aware of possible guided (Lamb) wave effects or reflection...

  8. S wave velocity structure below central Mexico using highresolution surface wave tomography

    E-Print Network [OSTI]

    Clayton, Robert W.

    to the coast and found significant difference between the two paths in the period range of 5 to 35 s. [4 regions; they also show a wellresolved lowvelocity zone just below the active part of the Trans Mexican zone. This knowledge is also critical in understanding amplification of seismic waves as they propagate

  9. A study of vacuum arc ion velocities using a linear set of probes

    E-Print Network [OSTI]

    Hohenbild, Stefan

    2008-01-01

    method; aluminum plasma; arc current constant at 200 A.velocity in vacuum arc plasmas by arc current perturbationin the vicinity of the arc plasma source. submitted to J.

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

    E-Print Network [OSTI]

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

    2006-02-25

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

  11. Exploring Classically Chaotic Potentials with a Matter Wave Quantum Probe

    SciTech Connect (OSTI)

    Gattobigio, G. L. [Laboratoire de Collisions Agregats Reactivite, CNRS UMR 5589, IRSAMC, Universite de Toulouse (UPS), 118 Route de Narbonne, 31062 Toulouse CEDEX 4 (France); Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 rue Lhomond, 75005 Paris (France); Couvert, A. [Laboratoire Kastler Brossel, Ecole Normale Superieure, 24 rue Lhomond, 75005 Paris (France); Georgeot, B. [Laboratoire de Physique Theorique (IRSAMC), Universite de Toulouse (UPS), 31062 Toulouse (France); CNRS, LPT UMR5152 (IRSAMC), 31062 Toulouse (France); Guery-Odelin, D. [Laboratoire de Collisions Agregats Reactivite, CNRS UMR 5589, IRSAMC, Universite de Toulouse (UPS), 118 Route de Narbonne, 31062 Toulouse CEDEX 4 (France)

    2011-12-16

    We study an experimental setup in which a quantum probe, provided by a quasimonomode guided atom laser, interacts with a static localized attractive potential whose characteristic parameters are tunable. In this system, classical mechanics predicts a transition from regular to chaotic behavior as a result of the coupling between the different degrees of freedom. Our experimental results display a clear signature of this transition. On the basis of extensive numerical simulations, we discuss the quantum versus classical physics predictions in this context. This system opens new possibilities for investigating quantum scattering, provides a new testing ground for classical and quantum chaos, and enables us to revisit the quantum-classical correspondence.

  12. Measurement of shear wave velocity of heavy oil De-hua Han, Jiajin Liu, University of Houston

    E-Print Network [OSTI]

    1 Measurement of shear wave velocity of heavy oil De-hua Han, Jiajin Liu, University of Houston modulus and therefore no shear wave can propagate through fluids. But heavy oils have properties that are much complex than lighter oils. At low temperatures, heavy oils are extremely viscous and begin to act

  13. The thin section rock physics: Modeling and measurement of seismic wave velocity on the slice of carbonates

    SciTech Connect (OSTI)

    Wardaya, P. D. Noh, K. A. B. M. Yusoff, W. I. B. W.; Ridha, S.; Nurhandoko, B. E. B.

    2014-09-25

    This paper discusses a new approach for investigating the seismic wave velocity of rock, specifically carbonates, as affected by their pore structures. While the conventional routine of seismic velocity measurement highly depends on the extensive laboratory experiment, the proposed approach utilizes the digital rock physics view which lies on the numerical experiment. Thus, instead of using core sample, we use the thin section image of carbonate rock to measure the effective seismic wave velocity when travelling on it. In the numerical experiment, thin section images act as the medium on which wave propagation will be simulated. For the modeling, an advanced technique based on artificial neural network was employed for building the velocity and density profile, replacing image's RGB pixel value with the seismic velocity and density of each rock constituent. Then, ultrasonic wave was simulated to propagate in the thin section image by using finite difference time domain method, based on assumption of an acoustic-isotropic medium. Effective velocities were drawn from the recorded signal and being compared to the velocity modeling from Wyllie time average model and Kuster-Toksoz rock physics model. To perform the modeling, image analysis routines were undertaken for quantifying the pore aspect ratio that is assumed to represent the rocks pore structure. In addition, porosity and mineral fraction required for velocity modeling were also quantified by using integrated neural network and image analysis technique. It was found that the Kuster-Toksoz gives the closer prediction to the measured velocity as compared to the Wyllie time average model. We also conclude that Wyllie time average that does not incorporate the pore structure parameter deviates significantly for samples having more than 40% porosity. Utilizing this approach we found a good agreement between numerical experiment and theoretically derived rock physics model for estimating the effective seismic wave velocity of rock.

  14. Inertial waves and mean velocity profiles in a rotating pipe and a circular annulus with axial flow

    E-Print Network [OSTI]

    Yang, Yantao; Wu, J Z; Orlandi, Paolo

    2015-01-01

    In this paper we solve the inviscid inertial wave solutions in a circular pipe or annulus rotating constantly about its axis with moderate angular speed. The solutions are constructed by the so-called helical wave functions. We reveal that the mean velocity profiles must satisfy certain conditions to accommodate the inertial waves at the bulk region away from boundary. These conditions require the axial and azimuthal components of the mean velocity take the shapes of the zeroth and first order Bessel functions of the first kind, respectively. The theory is then verified by data obtained from direct numerical simulations for both rotating pipe and circular annulus, and excellent agreement is found between theory and numerical results. Large scale vortex clusters are found in the bulk region where the mean velocity profiles match the theoretical predictions. The success of the theory in rotating pipe, circular annulus, and streamwise rotating channel suggests that such inertial waves are quite common in wall bo...

  15. Stochastic simulation for the propagation of high-frequency acoustic waves through a random velocity field

    SciTech Connect (OSTI)

    Lu, B.; Darmon, M.; Leymarie, N.; Chatillon, S.; Potel, C.

    2012-05-17

    In-service inspection of Sodium-Cooled Fast Reactors (SFR) requires the development of non-destructive techniques adapted to the harsh environment conditions and the examination complexity. From past experiences, ultrasonic techniques are considered as suitable candidates. The ultrasonic telemetry is a technique used to constantly insure the safe functioning of reactor inner components by determining their exact position: it consists in measuring the time of flight of the ultrasonic response obtained after propagation of a pulse emitted by a transducer and its interaction with the targets. While in-service the sodium flow creates turbulences that lead to temperature inhomogeneities, which translates into ultrasonic velocity inhomogeneities. These velocity variations could directly impact the accuracy of the target locating by introducing time of flight variations. A stochastic simulation model has been developed to calculate the propagation of ultrasonic waves in such an inhomogeneous medium. Using this approach, the travel time is randomly generated by a stochastic process whose inputs are the statistical moments of travel times known analytically. The stochastic model predicts beam deviations due to velocity inhomogeneities, which are similar to those provided by a determinist method, such as the ray method.

  16. PUBLISHED ONLINE: 5 FEBRUARY 2012 | DOI: 10.1038/NPHYS2217 Local probing of propagating acoustic waves in a

    E-Print Network [OSTI]

    Loss, Daniel

    acoustic waves in a gigahertz echo chamber Martin V. Gustafsson1 *, Paulo V. Santos2 , Göran Johansson1, surface acoustic waves resemble the sound these instruments produce, but moving over a solid surface probing of surface acoustic waves with a displacement sensitivity of 30 amRMS Hz-1/2 and detection

  17. Probing the Inhomogeneous Universe with Gravitational Wave Cosmology

    E-Print Network [OSTI]

    Kent Yagi; Atsushi Nishizawa; Chul-Moon Yoo

    2012-04-07

    If we assume that we live in the center of a spherical inhomogeneous universe, we can explain the apparent accelerating expansion of the universe without introducing the unknown dark energy or modifying gravitational theory. Direct measurement of the cosmic acceleration can be a powerful tool in distinguishing $\\Lambda$CDM and the inhomogeneous models. If $\\Lambda$CDM is the correct model, we have shown that DECIGO/BBO has sufficient ability to detect the positive redshift drift of the source by observing gravitational waves from neutron star binaries for 5-10 years. This enables us to rule out any Lema\\^itre-Tolman-Bondi (LTB) void model with monotonically increasing density profile. Furthermore, by detecting the positive redshift drift at $z\\sim 0$, we can even rule out generic LTB models unless we allow unrealistically steep density gradient at $z\\sim 0$. We also show that the measurement accuracy is slightly improved when we consider the joint search of DECIGO/BBO and the third generation Einstein Telescope. This test can be performed with GW observations alone without any reference to electromagnetic observations.

  18. Probing Long Gamma Ray Bursts progenitor mass by Gravitational Waves

    E-Print Network [OSTI]

    De Laurentis, Mariafelicia; Dainotti, Maria Giovanna; Milano, Leopoldo

    2015-01-01

    In this work we present a procedure to infer the mass of progenitors and remnants of Gamma Ray Bursts (GRB), starting from the observed energy $E_{iso}^{GRB}$ emitted isotropically and considering the associated emission of Gravitational Waves (GW) $ E_{iso}^{GW}$ in the different phases. We assume that the GW energy of the progenitor $E_{PROG}^{GW}$ is emitted partially during a star collapse, and the residual energy is related to the GW energy emitted by the remnant. We take a sample of $237$ Long GRB, and use an hybrid Montecarlo procedure to explore, for each of them, a region of possible solutions of $ E_{iso}^{GW}$ as a function of the masses, radii, oblateness, rotation frequencies of progenitor and remnant and the fraction of energy $k$ emitted as GW by the GRB. We discriminate between a Neutron Star (NS) or Black Hole (BH) for the remnant and obtain interesting values for the GW emitted by the remnant NS or BH, for the conversion factor $k$ of and for the masses and radii of GRB progenitor stars. We ...

  19. FLUID-INDUCED CHANGES IN SHEAR VELOCITY FROM SURFACE WAVES Michael West and William Menke, Lamont-Doherty Earth Observatory and Department of Earth

    E-Print Network [OSTI]

    West, Michael

    respond to changes in the bulk modulus, shear modulus and density caused by the presence of water. WeFLUID-INDUCED CHANGES IN SHEAR VELOCITY FROM SURFACE WAVES Michael West and William Menke, Lamont transient ground water by detecting changes in seismic velocity. Compressional and shear wave velocities

  20. Probing the size of extra dimension with gravitational wave astronomy

    E-Print Network [OSTI]

    Kent Yagi; Norihiro Tanahashi; Takahiro Tanaka

    2011-12-28

    In Randall-Sundrum II (RS-II) braneworld model, it has been conjectured according to the AdS/CFT correspondence that brane-localized black hole (BH) larger than the bulk AdS curvature scale $\\ell$ cannot be static, and it is dual to a four dimensional BH emitting the Hawking radiation through some quantum fields. In this scenario, the number of the quantum field species is so large that this radiation changes the orbital evolution of a BH binary. We derived the correction to the gravitational waveform phase due to this effect and estimated the upper bounds on $\\ell$ by performing Fisher analyses. We found that DECIGO/BBO can put a stronger constraint than the current table-top result by detecting gravitational waves from small mass BH/BH and BH/neutron star (NS) binaries. Furthermore, DECIGO/BBO is expected to detect 10$^5$ BH/NS binaries per year. Taking this advantage, we found that DECIGO/BBO can actually measure $\\ell$ down to $\\ell=0.33 \\mu$m for 5 year observation if we know that binaries are circular a priori. This is about 40 times smaller than the upper bound obtained from the table-top experiment. On the other hand, when we take eccentricities into binary parameters, the detection limit weakens to $\\ell=1.5 \\mu$m due to strong degeneracies between $\\ell$ and eccentricities. We also derived the upper bound on $\\ell$ from the expected detection number of extreme mass ratio inspirals (EMRIs) with LISA and BH/NS binaries with DECIGO/BBO, extending the discussion made recently by McWilliams. We found that these less robust constraints are weaker than the ones from phase differences.

  1. MEASUREMENT OF COMPRESSIONAL-WAVE SEISMIC VELOCITIES IN 29 WELLS AT THE HANFORD SITE

    SciTech Connect (OSTI)

    PETERSON SW

    2010-10-08

    Check shot seismic velocity surveys were collected in 100 B/C, 200 East, 200-PO-1 Operational Unit (OU), and the Gable Gap areas in order to provide time-depth correlation information to aid the interpretation of existing seismic reflection data acquired at the Hanford Site (Figure 1). This report details results from 5 wells surveyed in fiscal year (FY) 2008, 7 wells in FY 2009, and 17 wells in FY 2010 and provides summary compressional-wave seismic velocity information to help guide future seismic survey design as well as improve current interpretations of the seismic data (SSC 1979/1980; SGW-39675; SGW-43746). Augmenting the check shot database are four surveys acquired in 2007 in support of the Bechtel National, Inc. Waste Treatment Plant construction design (PNNL-16559, PNNL-16652), and check shot surveys in three wells to support seismic testing in the 200 West Area (Waddell et al., 1999). Additional sonic logging was conducted during the late 1970s and early 1980s as part of the Basalt Waste Isolation Program (BWIP) (SSC 1979/1980) and check shot/sonic surveys as part of the safety report for the Skagit/Hanford Nuclear project (RDH/10-AMCP-0164). Check shot surveys are used to obtain an in situ measure of compressional-wave seismic velocity for sediment and rock in the vicinity of the well point, and provide the seismic-wave travel time to geologic horizons of interest. The check shot method deploys a downhole seismic receiver (geophone) to record the arrival of seismic waves generated by a source at the ground surface. The travel time of the first arriving seismic-wave is determined and used to create a time-depth function to correlate encountered geologic intervals with the seismic data. This critical tie with the underlying geology improves the interpretation of seismic reflection profile information. Fieldwork for this investigation was conducted by in house staff during the weeks of September 22, 2008 for 5 wells in the 200 East Area (Figure 2); June 1, 2009 for 7 wells in the 200-PO-1 OU and Gable Gap regions (see Figure 3 and Figure 4); and March 22, 2010 and April 19, 2010 for 17 wells in the 200 East, The initial scope of survey work was planned for Wells 299-EI8-1, 699-2-E14, 699-12-18, 699-16-51, 699-42-30, 699-53-55B, 699-54-18D, and 699-84-34B. Well 299-E18-1 could not be entered due to bent casing (prevented removal of the pump), wells 699-12-18 and 699-42-30 could not be safely reached by the logging truck, Well 699-16-51 was decommissioned prior to survey start, Well 699-53-55B did not have its pump pulled, and Wells 699-2-EI4, 699-54-18D, and 699-84-34B are artesian and capped with an igloo structure. Table 1 provides a list of wells that were surveyed and Figure 1 through Figure 5 show the well locations relative to the Hanford Site.

  2. Seismic Velocity Structure and Depth-Dependence of Anisotropy in the Red Sea and Arabian Shield from Surface Wave Analysis

    SciTech Connect (OSTI)

    Hansen, S; Gaherty, J; Schwartz, S; Rodgers, A; Al-Amri, A

    2007-07-25

    We investigate the lithospheric and upper mantle structure as well as the depth-dependence of anisotropy along the Red Sea and beneath the Arabian Peninsula using receiver function constraints and phase velocities of surface waves traversing two transects of stations from the Saudi Arabian National Digital Seismic Network. Frequency-dependent phase delays of fundamental-mode Love and Rayleigh waves, measured using a cross-correlation procedure, require very slow shear velocities and the presence of anisotropy throughout the upper mantle. Linearized inversion of these data produce path-averaged 1D radially anisotropic models with about 4% anisotropy in the lithosphere, increasing to about 4.8% anisotropy across the lithosphere-asthenosphere boundary (LAB). Models with reasonable crustal velocities in which the mantle lithosphere is isotropic cannot satisfy the data. The lithospheric lid, which ranges in thickness from about 70 km near the Red Sea coast to about 90 km beneath the Arabian Shield, is underlain by a pronounced low-velocity zone with shear velocities as low as 4.1 km/s. Forward models, which are constructed from previously determined shear-wave splitting estimates, can reconcile surface and body wave observations of anisotropy. The low shear velocity values are similar to many other continental rift and oceanic ridge environments. These low velocities combined with the sharp velocity contrast across the LAB may indicate the presence of partial melt beneath Arabia. The anisotropic signature primarily reflects a combination of plate- and density-driven flow associated with active rifting processes in the Red Sea.

  3. Observation of an extrinsic critical velocity using matter wave interferometry Yuki Sato, Aditya Joshi, and Richard Packard

    E-Print Network [OSTI]

    Sato, Yuki

    to the initial onset of a single vortex motion. We place a flow tube in one arm of a matter wave interferometer and directly monitor the order-parameter phase difference across the tube's ends. When a vortex initially quantum interference device to probe the initial onset of the motion of a single vortex line driven

  4. Joint migration velocity analysis of PP-and PS-waves for VTI media Pengfei Cai1

    E-Print Network [OSTI]

    Tsvankin, Ilya

    estimated, accurate depth images can be obtained by migrating the recorded PP and PS data. INTRODUCTION Prestack depth migration (PSDM) and reflection tomography in the migrated domain are widely used in PJoint migration velocity analysis of PP- and PS-waves for VTI media Pengfei Cai1 and Ilya Tsvankin2

  5. Green's Functions for Surface Waves in a Generic Velocity Structure by Victor C. Tsai and Sarun Atiganyanun*

    E-Print Network [OSTI]

    Tsai, Victor C.

    , it is not in others. Moreover, calculating the complete Green's functions for a specific case may take significantShort Note Green's Functions for Surface Waves in a Generic Velocity Structure by Victor C. Tsai displacement/stress eigenfunctions and Green's functions have been well established for many decades. However

  6. Derivation of site-specific relationships between hydraulic parameters and p-wave velocities based on hydraulic and seismic tomography

    SciTech Connect (OSTI)

    Brauchler, R.; Doetsch, J.; Dietrich, P.; Sauter, M.

    2012-01-10

    In this study, hydraulic and seismic tomographic measurements were used to derive a site-specific relationship between the geophysical parameter p-wave velocity and the hydraulic parameters, diffusivity and specific storage. Our field study includes diffusivity tomograms derived from hydraulic travel time tomography, specific storage tomograms, derived from hydraulic attenuation tomography, and p-wave velocity tomograms, derived from seismic tomography. The tomographic inversion was performed in all three cases with the SIRT (Simultaneous Iterative Reconstruction Technique) algorithm, using a ray tracing technique with curved trajectories. The experimental set-up was designed such that the p-wave velocity tomogram overlaps the hydraulic tomograms by half. The experiments were performed at a wellcharacterized sand and gravel aquifer, located in the Leine River valley near Göttingen, Germany. Access to the shallow subsurface was provided by direct-push technology. The high spatial resolution of hydraulic and seismic tomography was exploited to derive representative site-specific relationships between the hydraulic and geophysical parameters, based on the area where geophysical and hydraulic tests were performed. The transformation of the p-wave velocities into hydraulic properties was undertaken using a k-means cluster analysis. Results demonstrate that the combination of hydraulic and geophysical tomographic data is a promising approach to improve hydrogeophysical site characterization.

  7. Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections

    DOE Patents [OSTI]

    DiMambro, Joseph (Placitas, NM); Roach, Dennis P. (Albuquerque, NM); Rackow, Kirk A. (Albuquerque, NM); Nelson, Ciji L. (Albuquerque, NM); Dasch, Cameron J. (Boomfield Hills, MI); Moore, David G. (Albuquerque, NM)

    2012-01-03

    An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

  8. Ultrasonic probe deployment device for increased wave transmission and rapid area scan inspections

    DOE Patents [OSTI]

    DiMambro, Joseph; Roach, Dennis P; Rackow, Kirk A; Nelson, Ciji L; Dasch, Cameron J; Moore, David G

    2013-02-12

    An ultrasonic probe deployment device in which an ultrasound-transmitting liquid forms the portion of the ultrasonic wave path in contact with the surface being inspected (i.e., the inspection surface). A seal constrains flow of the liquid, for example preventing the liquid from surging out and flooding the inspection surface. The seal is not rigid and conforms to variations in the shape and unevenness of the inspection surface, thus forming a seal (although possibly a leaky seal) around the liquid. The probe preferably is held in place to produce optimum ultrasonic focus on the area of interest. Use of encoders can facilitate the production of C-scan area maps of the material being inspected.

  9. Probing the noncommutative structure of space with a quantum harmonic oscillator driven by gravitational wave

    E-Print Network [OSTI]

    Saha, Anirban

    2015-01-01

    We investigate the quantum mechanical transitions, induced by the combined effect of Gravitational wave (GW) and noncommutative (NC) structure of space, among the states of a 2-dimensional harmonic oscillator. The phonon modes excited by the passing GW within the resonant bar-detector are formally identical to forced harmonic oscillator and they represent a length variation of roughly the same order of magnitude as the characteristic length-scale of spatial noncommutativity estimated from the phenomenological upper bound of the NC parameter. This motivates our present work. We employ a number of different GW wave-forms that are typically expected from possible astronomical sources. We find that the transition probablities are quite sensitive to the nature of polarization of the GW. We further elaborate on the particular type of sources of GW radiation which can induce transitions that can be used as effective probe of the spatial noncommutative structure.

  10. Shear Wave Velocity Structure of Southern African Crust: Evidence for Compositional Heterogeneity within Archaean and Proterozoic Terrains

    SciTech Connect (OSTI)

    Kgaswane, E M; Nyblade, A A; Julia, J; Dirks, P H H M; Durrheim, R J; Pasyanos, M E

    2008-11-11

    Crustal structure in southern Africa has been investigated by jointly inverting receiver functions and Rayleigh wave group velocities for 89 broadband seismic stations spanning much of the Precambrian shield of southern Africa. 1-D shear wave velocity profiles obtained from the inversion yield Moho depths that are similar to those reported in previous studies and show considerable variability in the shear wave velocity structure of the lower part of the crust between some terrains. For many of the Archaean and Proterozoic terrains in the shield, S velocities reach 4.0 km/s or higher over a substantial part of the lower crust. However, for most of the Kimberley terrain and adjacent parts of the Kheis Province and Witwatersrand terrain, as well as for the western part of the Tokwe terrain, mean shear wave velocities of {le} 3.9 km/s characterize the lower part of the crust along with slightly ({approx}5 km) thinner crust. These findings indicate that the lower crust across much of the shield has a predominantly mafic composition, except for the southwest portion of the Kaapvaal Craton and western portion of the Zimbabwe Craton, where the lower crust is intermediate-to-felsic in composition. The parts of the Kaapvaal Craton underlain by intermediate-to-felsic lower crust coincide with regions where Ventersdorp rocks have been preserved, and thus we suggest that the intermediate-to-felsic composition of the lower crust and the shallower Moho may have resulted from crustal melting during the Ventersdorp tectonomagmatic event at c. 2.7 Ga and concomitant crustal thinning caused by rifting.

  11. The Magnetic Field Sign Reversal and Evolution of Rossby and Alfven Waves Induced by Velocity Shear Oscillations on the Sun

    E-Print Network [OSTI]

    A. D. Pataraya; T. A. Pataraya; B. M. Shergelashvili

    2000-05-08

    The behaviour of the toroidal and meridional components of the solar large-scale magnetic field and linear Alfven and Rossby waves during solar activity cycles and bi-annual time periods are theoretically investigated in this work. We consider the case of periodical velocity shear with bi-annual oscillation period . The large-scale magnetic field toroidal and meridional components are obtained as harmonic functions of the time. The sign reversal of these magnetic field components is studied. The numerical simulations show that, due to the velocity shear oscillations, the toroidal or meridional component of the large-scale magnetic field reverses its sign three times in one of the hemispheres (northern or southern) of the Sun, during the solar activity cycle 23. According to our results the appearance of velocity shear oscillations leads to the modulation of the magnetic field 22-year period oscillations by the bi-annual ones. The presented model is applicable for investigation of the magnetic field evolution at the base of convection zone as well as for understanding the magnetic field properties in the upper solar atmosphere. The excitement of the linear Rossby and Alfven waves in the shear layer at the base of the convection zone is also considered. The periodical impulsive growth is characteristic to the energy density of Alfven and Rossby waves and they propagate as localized in time powerful pulses. Such behavior of waves well explains mechanisms of the solar flare excitement and activity.

  12. Probes

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgramExemptions | National Nuclear SecurityRecords |JanoschekProbes for

  13. Quantitative degenerate four-wave mixing spectroscopy: Probes for molecular species

    SciTech Connect (OSTI)

    Farrow, R.; Rakestraw, D.; Paul, P.; Lucht, R.; Danehy, P.; Friedman-Hill, E.; Germann, G. [Sandia National Laboratories, Livermore, CA (United States)

    1993-12-01

    Resonant degenerate four-wave mixing (DFWM) is currently the subject of intensive investigation as a sensitive diagnostic tool for molecular species. DFWM has the advantage of generating a coherent (beam-like) signal which results in null-background detection and provides excellent immunity to background-light interference. Since multiple one-photon resonances are involved in the signal generation process, the DFWM technique can allow sensitive detection of molecules via electronic, vibrational or rotational transitions. These properties combine to make DFWM a widely applicable diagnostic technique for the probing of molecular species. The authors are conducting fundamental and applied investigations of DFWM for quantitative measurements of trace species in reacting gases. During the past year, efforts have been focussed in two areas: (1) understanding the effects of collisional processes on the DFWM signal generation process, and (2) exploring the applicability of infrared DFWM to detect polyatomic molecules via rovibrational transitions.

  14. Anisotropies of gravitational-wave standard sirens as a new cosmological probe without redshift information

    E-Print Network [OSTI]

    Namikawa, Toshiya; Taruya, Atsushi

    2015-01-01

    Compact binary stars at cosmological distances are promising sources for gravitational waves (GWs), and these are thought to be powerful cosmological probes, referred to as the GW standard sirens. With future GW detectors such as the Einstein telescope (ET), we will be able to precisely measure their luminosity distances out to a redshift $z\\sim5$. While previously proposed cosmological studies using the GW standard sirens require redshift information for each source, which could be obtained through an extensive electromagnetic follow-up campaign, we here propose an alternative method only with the luminosity distances. Utilizing the anisotropies of the number density and luminosity distances originated from the large-scale structure, we discuss how this anisotropies can be measured and are sensitive to the cosmology, finding that the expected constraints on the primordial non-Gaussianity parameter $f_{\\rm NL}$ could become $\\sigma(f_{\\rm NL})=0.54$ with a network of ET-like detectors.

  15. Inversion of OBC seismic data for P- and S-wave velocities

    E-Print Network [OSTI]

    Hall, Guy R

    This thesis describes an new method for deriving a shared-earth velocity model for P-P ans P-SV reflections measured with ocean bottom cable (OBC) data. The data have the potential to reveal lithological and fluid ...

  16. Probing the thermal character of analogue Hawking radiation for shallow water waves?

    E-Print Network [OSTI]

    Florent Michel; Renaud Parentani

    2014-09-15

    We study and numerically compute the scattering coefficients of shallow water waves blocked by a stationary counterflow. When the flow is transcritical, the coefficients closely follow Hawking's prediction according to which black holes should emit a thermal spectrum. We study how the spectrum deviates from thermality when reducing the maximal flow velocity, with a particular attention to subcritical flows since these have been recently used to test Hawking's prediction. For such flows, we show that the emission spectrum is strongly suppressed, and that its Planckian character is completely lost. For low frequencies, we also show that the scattering coefficients are dominated by elastic hydrodynamical channels. Our numerical results reproduce rather well the observations made by S. Weinfurtner {\\it et al.} in the Vancouver experiment. Nevertheless, we propose a new interpretation of what has been observed, as well as new experimental tests.

  17. Group velocity of acoustic waves in strongly scattering media: Dependence on the volume fraction of scatterers

    E-Print Network [OSTI]

    Page, John

    the solid scatterers, and by ii tortuosity effects, where the wave energy is largely confined University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong Received 4 June 1998 We study, both

  18. One-Way Wave Propagators For Velocity Analysis On Curvilinear Coordinates

    E-Print Network [OSTI]

    Budkick, Scott

    2008-01-01

    Due to present computational limitations, migration by the one-way wave equation remains an integral tool in seismic exploration. For the realistic interpretation of common image point gathers, it is necessary that migration ...

  19. Bulletin of the Seismological Society of America, Vol. 94, No. 6, pp. 22222228, December 2004 A Shallow Shear-Wave Velocity Transect

    E-Print Network [OSTI]

    , 1997) provisions (Building Seismic Safety Council [BSSC], 1998) sites are categorized for shaking-wave velocity measure- ments in the basin to be able to assess the success of alter- native NEHRP classification. Ambient seismic noise (vehicle traffic, etc.) excited Rayleigh waves in urban alluvium, eliminating

  20. Applying the cold plasma dispersion relation to whistler mode chorus waves: EMFISIS wave measurements from the Van Allen Probes

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

    Hartley, D. P.; Chen, Y.; Kletzing, C. A.; Denton, M. H.; Kurth, W. S.

    2015-02-17

    Most theoretical wave models require the power in the wave magnetic field in order to determine the effect of chorus waves on radiation belt electrons. However, researchers typically use the cold plasma dispersion relation to approximate the magnetic wave power when only electric field data are available. In this study, the validity of using the cold plasma dispersion relation in this context is tested using Electric and Magnetic Field Instrument Suite and Integrated Science (EMFISIS) observations of both the electric and magnetic spectral intensities in the chorus wave band (0.1–0.9 fce). Results from this study indicate that the calculated wavemore »intensity is least accurate during periods of enhanced wave activity. For observed wave intensities >10?³ nT², using the cold plasma dispersion relation results in an underestimate of the wave intensity by a factor of 2 or greater 56% of the time over the full chorus wave band, 60% of the time for lower band chorus, and 59% of the time for upper band chorus. Hence, during active periods, empirical chorus wave models that are reliant on the cold plasma dispersion relation will underestimate chorus wave intensities to a significant degree, thus causing questionable calculation of wave-particle resonance effects on MeV electrons.« less

  1. Contribution of Velocity Vortices and Fast Shock Reflection and Refraction to the Formation of EUV Waves in Solar Eruptions

    E-Print Network [OSTI]

    Wang, Hongjuan; Gong, Jiancun; Wu, Ning; Lin, Jun

    2015-01-01

    We numerically study the detailed evolutionary features of the wave-like disturbance and its propagation in the eruption. This work is a follow-up to Wang et al., using significantly upgraded new simulations. We focus on the contribution of the velocity vortices and the fast shock reflection and refraction in the solar corona to the formation of the EUV waves. Following the loss of equilibrium in the coronal magnetic structure, the flux rope exhibits rapid motions and invokes the fast-mode shock forward of the rope, which then produces the type II radio burst. The expansion of the fast shock, which is associated with outward motion, takes place in various directions, and the downward expansion shows the reflection and the refraction as a result of the non-uniform background plasma. The reflected component of the fast shock propagates upward and the refracted component propagates downward. As the refracted component reaches the boundary surface, a weak echo is excited. The Moreton wave is invoked as the fast s...

  2. Structure of the Crust beneath Cameroon, West Africa, from the Joint Inversion of Rayleigh Wave Group Velocities and Receiver Functions

    SciTech Connect (OSTI)

    Tokam, A K; Tabod, C T; Nyblade, A A; Julia, J; Wiens, D A; Pasyanos, M E

    2010-02-18

    The Cameroon Volcanic Line (CVL) is a major geologic feature that cuts across Cameroon from the south west to the north east. It is a unique volcanic lineament which has both an oceanic and a continental sector and consists of a chain of Tertiary to Recent, generally alkaline volcanoes stretching from the Atlantic island of Pagalu to the interior of the African continent. The oceanic sector includes the islands of Bioko (formerly Fernando Po) and Sao Tome and Principe while the continental sector includes the Etinde, Cameroon, Manengouba, Bamboutos, Oku and Mandara mountains, as well as the Adamawa and Biu Plateaus. In addition to the CVL, three other major tectonic features characterize the region: the Benue Trough located northwest of the CVL, the Central African Shear Zone (CASZ), trending N70 degrees E, roughly parallel to the CVL, and the Congo Craton in southern Cameroon. The origin of the CVL is still the subject of considerable debate, with both plume and non-plume models invoked by many authors (e.g., Deruelle et al., 2007; Ngako et al, 2006; Ritsema and Allen, 2003; Burke, 2001; Ebinger and Sleep, 1998; Lee et al, 1994; Dorbath et al., 1986; Fairhead and Binks, 1991; King and Ritsema, 2000; Reusch et al., 2010). Crustal structure beneath Cameroon has been investigated previously using active (Stuart et al, 1985) and passive (Dorbath et al., 1986; Tabod, 1991; Tabod et al, 1992; Plomerova et al, 1993) source seismic data, revealing a crust about 33 km thick at the south-western end of the continental portion of the CVL (Tabod, 1991) and the Adamawa Plateau, and thinner crust (23 km thick) beneath the Garoua Rift in the north (Stuart et al, 1985) (Figure 1). Estimates of crustal thickness obtained using gravity data show similar variations between the Garoua rift, Adamawa Plateau, and southern part of the CVL (Poudjom et al., 1995; Nnange et al., 2000). In this study, we investigate further crustal structure beneath the CVL and the adjacent regions in Cameroon using 1-D shear wave velocity models obtained from the joint inversion of Rayleigh wave group velocities and P-receiver functions for 32 broadband seismic stations. From the 1-D shear wave velocity models, we obtain new insights into the composition and structure of the crust and upper mantle across Cameroon. After briefly reviewing the geological framework of Cameroon, we describe the data and the joint inversion method, and then interpret variations in crustal structure found beneath Cameroon in terms of the tectonic history of the region.

  3. Determination of elastic properties of a MnO{sub 2} coating by surface acoustic wave velocity dispersion analysis

    SciTech Connect (OSTI)

    Sermeus, J.; Glorieux, C.; Sinha, R.; Vereecken, P. M.; Vanstreels, K.

    2014-07-14

    MnO{sub 2} is a material of interest in the development of high energy-density batteries, specifically as a coating material for internal 3D structures, thus ensuring rapid energy deployment. Its electrochemical properties have been mapped extensively, but there are, to the best of the authors' knowledge, no records of the elastic properties of thin film MnO{sub 2}. Impulsive stimulated thermal scattering (ISTS), also known as the heterodyne diffraction or transient grating technique, was used to determine the Young's modulus (E) and porosity (?) of a 500?nm thick MnO{sub 2} coating on a Si(001) substrate. ISTS is an all optical method that is able to excite and detect surface acoustic waves (SAWs) on opaque samples. From the measured SAW velocity dispersion, the Young's modulus and porosity were determined to be E?=?25?±?1?GPa and ?=42±1%, respectively. These values were confirmed by independent techniques and determined by a most-squares analysis of the carefully fitted SAW velocity dispersion. This study demonstrates the ability of the presented technique to determine the elastic parameters of a thin, porous film on an anisotropic substrate.

  4. CARS is a four wave mixing process, combining three incident electric fields, pump, Stokes and probe, to produce a fourth, the anti-

    E-Print Network [OSTI]

    Greenaway, Alan

    CARS is a four wave mixing process, combining three incident electric fields, pump, Stokes diagram for the production of a CARS signal. The three incident waves pump, probe (both of frequency p) and Stokes (S) combine to produce an anti-Stokes signal, frequency as. Figure 2. Schematic of the CARS system

  5. Geophys. J. R. astr. SOC.(1987) 91,429437 On the relation between seismic wave velocity and stress in a solid

    E-Print Network [OSTI]

    Lyakhovsky, Vladimir

    1987-01-01

    -elastic isotropic models (Zaichenko et al. 1984; Schukin 1984). Interpretation of seismic results based on the Hooke in seismic zones implies that the traditional interpretation of geophysical investigations basedGeophys. J. R. astr. SOC.(1987) 91,429437 On the relation between seismic wave velocity and stress

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

    E-Print Network [OSTI]

    Gevorg Muradyan; A. Zh. Muradyan

    2009-08-21

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

  7. Near-extremal black holes as initial conditions of long GRB-supernovae and probes of their gravitational wave emission

    E-Print Network [OSTI]

    van Putten, Maurice H P M

    2015-01-01

    Long gamma-ray bursts (GRBs) associated with supernovae and short GRBs with Extended Emission (SGRBEE) from mergers are probably powered by black holes as a common inner engine, as their prompt GRB emission satisfies the same Amati correlation in the $E_{p,i}-E_{iso}$ plane. We introduce modified Bardeen equations to identify hyper-accretion driving newly formed black holes in core-collapse supernovae to near-extremal spin as a precursor to prompt GRB emission. Subsequent spin-down is observed in the BATSE catalog of long GRBs. Spin-down provides a natural unification of long durations associated with the lifetime of black hole spin for normal long GRBs and SGRBEEs, given the absence of major fallback matter in mergers. The results point to major emissions unseen in high frequency gravitational waves. A novel matched filtering method is described for LIGO-Virgo and KAGRA broadband probes of nearby core-collapse supernovae at essentially maximal sensitivity.

  8. 2011 Waves -1 STANDING WAVES

    E-Print Network [OSTI]

    Gustafsson, Torgny

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

  9. Experimental Probes of Radio Wave Propagation near Dielectric Boundaries and Implications for Neutrino Detection

    E-Print Network [OSTI]

    Alvarez, R; Hanson, J C; Johannesen, A M; Macy, J; Prohira, S; Stockham, J; Stockham, M; Zheng, Al; Zheng, Am

    2015-01-01

    Experimental efforts to measure neutrinos by radio-frequency (RF) signals resulting from neutrino interactions in-ice have intensified over the last decade. Recent calculations indicate that one may dramatically improve the sensitivity of ultra-high energy ("UHE"; >EeV) neutrino experiments via detection of radio waves trapped along the air-ice surface. Detectors designed to observe the "Askaryan effect" currently search for RF electromagnetic pulses propagating through bulk ice, and could therefore gain sensitivity if signals are confined to the ice-air boundary. To test the feasibilty of this scenario, measurements of the complex radio-frequency properties of several air-dielectric interfaces were performed for a variety of materials. Two-dimensional surfaces of granulated fused silica (sand), both in the lab as well as occurring naturally, water doped with varying concentrations of salt, natural rock salt formations, granulated salt and ice itself were studied, both in North America and also Antarctica. In...

  10. Gravity and the Collapse of the Wave Function: a Probe into Diósi-Penrose model

    E-Print Network [OSTI]

    Mohammad Bahrami; Andrea Smirne; Angelo Bassi

    2015-07-17

    We investigate the Di\\'osi-Penrose (DP) proposal for connecting the collapse of the wave function to gravity. The DP model needs a free parameter, acting as a cut-off to regularize the dynamics, and the predictions of the model highly depend on the value of this cut-off. The Compton wavelength of a nucleon seems to be the most reasonable cut-off value since it justifies the non-relativistic approach. However, with this value, the DP model predicts an unrealistic high rate of energy increase. Thus, one either is forced to choose a much larger cut-off, which is not physically justified and totally arbitrary, or one needs to include dissipative effects in order to tame the energy increase. Taking the analogy with dissipative collisional decoherence seriously, we develop a dissipative generalization of the DP model. We show that even with dissipative effects, the DP model contradicts known physical facts, unless either the cut-off is kept artificially large, or one limits the applicability of the model to massive systems. We also provide an estimation for the mass range of this applicability.

  11. Stochastic acceleration of electrons by fast magnetosonic waves in solar flares: the effects of anisotropy in velocity and wavenumber space

    SciTech Connect (OSTI)

    Pongkitiwanichakul, Peera; Chandran, Benjamin D. G.

    2014-11-20

    We develop a model for stochastic acceleration of electrons in solar flares. As in several previous models, the electrons are accelerated by turbulent fast magnetosonic waves ({sup f}ast waves{sup )} via transit-time-damping (TTD) interactions. (In TTD interactions, fast waves act like moving magnetic mirrors that push the electrons parallel or anti-parallel to the magnetic field). We also include the effects of Coulomb collisions and the waves' parallel electric fields. Unlike previous models, our model is two-dimensional in both momentum space and wavenumber space and takes into account the anisotropy of the wave power spectrum F{sub k} and electron distribution function f {sub e}. We use weak turbulence theory and quasilinear theory to obtain a set of equations that describes the coupled evolution of F{sub k} and f {sub e}. We solve these equations numerically and find that the electron distribution function develops a power-law-like non-thermal tail within a restricted range of energies E in (E {sub nt}, E {sub max}). We obtain approximate analytic expressions for E {sub nt} and E {sub max}, which describe how these minimum and maximum energies depend upon parameters such as the electron number density and the rate at which fast-wave energy is injected into the acceleration region at large scales. We contrast our results with previous studies that assume that F{sub k} and f {sub e} are isotropic, and we compare one of our numerical calculations with the time-dependent hard-X-ray spectrum observed during the 1980 June 27 flare. In our numerical calculations, the electron energy spectra are softer (steeper) than in models with isotropic F{sub k} and f {sub e} and closer to the values inferred from observations of solar flares.

  12. Modulational instability of ion-acoustic waves in a plasma with a q-nonextensive electron velocity distribution

    SciTech Connect (OSTI)

    Bains, A. S.; Gill, T. S.; Tribeche, Mouloud

    2011-02-15

    The modulational instability (MI) of ion-acoustic waves (IAWs) in a two-component plasma is investigated in the context of the nonextensive statistics proposed by Tsallis [J. Stat. Phys. 52, 479 (1988)]. Using the reductive perturbation method, the nonlinear Schroedinger equation (NLSE) which governs the MI of the IAWs is obtained. The presence of the nonextensive electron distribution is shown to influence the MI of the waves. Three different ranges of the nonextensive q-parameter are considered and in each case the MI sets in under different conditions. Furthermore, the effects of the q-parameter on the growth rate of MI are discussed in detail.

  13. P and S wave velocity and VP///VS in the wake of the Yellowstone hot spot

    E-Print Network [OSTI]

    Humphreys, Eugene

    magmatism occurred at the eastern Snake River Plain $6­10 m.y. B.P. Data are teleseismic P and S travel time. The dominant structure is a zone which extends beneath the Snake River Plain to a depth of $190 km that is high to density. Specifically, we infer that the low-velocity mantle beneath the Snake River Plain is partially

  14. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOE Patents [OSTI]

    Hall, Maclin S. (Marietta, GA); Jackson, Theodore G. (Atlanta, GA); Knerr, Christopher (Lawrenceville, GA)

    1998-02-17

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web.

  15. In-plane ultrasonic velocity measurement of longitudinal and shear waves in the machine direction with transducers in rotating wheels

    DOE Patents [OSTI]

    Hall, M.S.; Jackson, T.G.; Knerr, C.

    1998-02-17

    An improved system for measuring the velocity of ultrasonic signals within the plane of moving web-like materials, such as paper, paperboard and the like. In addition to velocity measurements of ultrasonic signals in the plane of the web in the MD and CD, one embodiment of the system in accordance with the present invention is also adapted to provide on-line indication of the polar specific stiffness of the moving web. In another embodiment of the invention, the velocity of ultrasonic signals in the plane of the web are measured by way of a plurality of ultrasonic transducers carried by synchronously driven wheels or cylinders, thus eliminating undue transducer wear due to any speed differences between the transducers and the web. In order to provide relatively constant contact force between the transducers and the webs, the transducers are mounted in a sensor housings which include a spring for biasing the transducer radially outwardly. The sensor housings are adapted to be easily and conveniently mounted to the carrier to provide a relatively constant contact force between the transducers and the moving web. 37 figs.

  16. 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

  17. Rogue Wave Modes for the Long WaveShort Wave Resonance Model Kwok Wing CHOW

    E-Print Network [OSTI]

    Rogue Wave Modes for the Long Wave­Short Wave Resonance Model Kwok Wing CHOW 1Ã , Hiu Ning CHAN 1 online June 11, 2013) The long wave­short 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 equations

  18. PHYSICAL REVIEW A 82, 013409 (2010) Theory of probing attosecond electron wave packets via two-path interference

    E-Print Network [OSTI]

    Lin, Chii-Dong

    2010-01-01

    . In quantum mechanics, each measurement is a projection of the dynamic system. Clearly, not all the probe for initiating a dynamical atomic or molecular system which evolves nontrivially in time, while retaining pulses (SAP) is still in its infancy. Thus, today only a handful of laboratories are capable

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

    SciTech Connect (OSTI)

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

    2014-11-15

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

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

    SciTech Connect (OSTI)

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

    2014-01-01

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

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

    E-Print Network [OSTI]

    of a long wave matches the group velocity of a short wave. Significant interactions and energy transfer can1 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

  2. GEOPHYSICALRESEARCHLETTERS, VOL. 20, NO. 5, PAGES391-394,MARCH 5, 1993 F_,LASC WAVE A'ITENUATiON AND VELOCITY OF BEREA SANDSTONE MEASURED

    E-Print Network [OSTI]

    'ITENUATiON AND VELOCITY OF BEREA SANDSTONE MEASURED IN THE FREQUENCY DOMAIN T. J. Shank!and1 Institutde.Usingmeasurementsinthefrequencydomainwe havemeasuredqualityfactorQandtraveltimesofdirectand side-reflectedelasticwavesin a 1.8mlongsampleofBerea sandstoneDVM. Possibletravelpathsinadditiontodirecttransmissioninclude sidewall reflectionsandsurfacewaves. 391 #12;392 Shanklandetal.:AttenuationandVelocityofSandstone

  3. Stress Wave Source Characterization: Impact, Fracture, and Sliding Friction

    E-Print Network [OSTI]

    McLaskey, Gregory Christofer

    2011-01-01

    717-725. Graff, K. (1975). Wave Motion in Elastic Solids (and deterioration on stress wave velocities in concrete,Greenspan, M. (1981) Surface-wave displacement: absolute

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

    E-Print Network [OSTI]

    Cary, John R.

    2012-01-01

    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,

  5. Azimuthally Anisotropic 3D Velocity Continuation

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

    Burnett, William; Fomel, Sergey

    2011-01-01

    We extend time-domain velocity continuation to the zero-offset 3D azimuthally anisotropic case. Velocity continuation describes how a seismic image changes given a change in migration velocity. This description turns out to be of a wave propagation process, in which images change along a velocity axis. In the anisotropic case, the velocity model is multiparameter. Therefore, anisotropic image propagation is multidimensional. We use a three-parameter slowness model, which is related to azimuthal variations in velocity, as well as their principal directions. This information is useful for fracture and reservoir characterization from seismic data. We provide synthetic diffraction imaging examples to illustratemore »the concept and potential applications of azimuthal velocity continuation and to analyze the impulse response of the 3D velocity continuation operator.« less

  6. Temporal Velocity Variations beneath the Coso Geothermal Field...

    Open Energy Info (EERE)

    Temporal Velocity Variations beneath the Coso Geothermal Field Observed using Seismic Double Difference Tomography of Compressional and Shear Wave Arrival Times Jump to:...

  7. Local Energy Velocity of Classical Fields

    E-Print Network [OSTI]

    I. V. Drozdov; A. A. Stahlhofen

    2007-04-19

    It is proposed to apply a recently developed concept of local wave velocities to the dynamical field characteristics, especially for the canonical field energy density. It is shown that local energy velocities can be derived from the lagrangian directly. The local velocities of zero- and first- order for energy propagation has been obtained for special cases of scalar and vector fields. Some important special cases of these results are discussed.

  8. Local tunneling characteristics near a grain boundary of a d-wave superconductor as probed by a normal-metal or a low-Tc-superconductor STM tip 

    E-Print Network [OSTI]

    Zhao, Hongwei

    2005-08-29

    We studied the local single-particle tunneling characteristics [as observed with scanning tunnel microscopy (STM)] for N D and S D tunneling, where N is a normal metal, S is a s-wave superconductor, and D is a d-wave ...

  9. Generic air sampler probe tests

    SciTech Connect (OSTI)

    Glissmeyer, J.A.; Ligotke, M.W.

    1995-11-01

    Tests were conducted to determine the best nozzle and probe designs for new air sampling systems to be installed in the ventilation systems of some of the waste tanks at the Hanford Site in Richland, Washington. Isokinetic nozzle probes and shrouded probes were tested. The test aerosol was sodium-fluorescein-tagged oleic acid. The test parameters involved particle sizes from 1 to 15 {mu}m, air velocities from 3 to 15 m/s. The results of the tests show that shrouded probes can deliver samples with significantly less particle-size bias then the isokinetic nozzle probes tested. Tests were also conducted on two sample flow splitters to determine particle loss as a function of aerodynamic particle size. The particle size range covered in these tests was 5 to 15 {mu}m. The results showed little particle loss, but did show a bias in particle concentration between the two outlets of each splitter for the larger particle sizes.

  10. Laser generation and detection of longitudinal and shear acoustic waves in a diamond anvil cell

    SciTech Connect (OSTI)

    Chigarev, Nikolay; Zinin, Pavel; Ming Lichung; Amulele, George; Bulou, Alain; Gusev, Vitalyi

    2008-11-03

    Laser ultrasonics in a point-source-point-receiver configuration is applied for the evaluation of elastic properties of nontransparent materials in a diamond anvil cell at high pressures. Measurement of both longitudinal and shear acoustic wave velocities in an iron foil at pressures up to 23 GPa does not require any information in addition to the one obtained by all-optical pump-probe technique.

  11. A Bayesian Approach to Assess the Importance of Crustal Corrections in Global Anisotropic Surface Wave Tomography

    E-Print Network [OSTI]

    Xing, Z; Beghein, C

    2015-01-01

    from measurements of surface wave phase velocity anomalies,boundary from surface wave dispersion data, J. Geophys.radially anisotropic surface wave tomography, J. Geophys.

  12. Recent Advances in Wave Travel Time Based Methodology for Structural Health Monitoring

    E-Print Network [OSTI]

    Southern California, University of

    identify wave velocity profiles of vertically propagating shear and torsional waves through the building monitoring, seismic interferometry, wave travel time 1. INTRODUCTION The ability to monitor the health

  13. Body Wave Tomography For Regional Scale Assessment Of Geothermal...

    Open Energy Info (EERE)

    wave tomography are two of the primary methods for estimation of regional scale seismic velocity variations. Seismic velocity is affected by temperature and rock composition...

  14. Wave Mechanics and the Fifth Dimension

    E-Print Network [OSTI]

    Paul S. Wesson; James M. Overduin

    2013-01-28

    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.

  15. IWA : an analysis program for isentropic wave measurements.

    SciTech Connect (OSTI)

    Ao, Tommy

    2009-02-01

    IWA (Isentropic Wave Analysis) is a program for analyzing velocity profiles of isentropic compression experiments. IWA applies incremental impedance matching correction to measured velocity profiles to obtain in-situ particle velocity profiles for Lagrangian wave analysis. From the in-situ velocity profiles, material properties such as wave velocities, stress, strain, strain rate, and strength are calculated. The program can be run in any current version of MATLAB (2008a or later) or as a Windows XP executable.

  16. Pyrotechnic deflagration velocity and permeability

    SciTech Connect (OSTI)

    Begeal, D R; Stanton, P L

    1982-01-01

    Particle size, porosity, and permeability of the reactive material have long been considered to be important factors in propellant burning rates and the deflagration-to-detonation transition in explosives. It is reasonable to assume that these same parameters will also affect the deflagration velocity of pyrotechnics. This report describes an experimental program that addresses the permeability of porous solids (particulate beds), in terms of particle size and porosity, and the relationship between permeability and the behavior of pyrotechnics and explosives. The experimental techniques used to acquire permeability data and to characterize the pyrotechnic burning are discussed. Preliminary data have been obtained on the burning characteristics of titanium hydride/potassium perchlorate (THKP) and boron/calcium chromate (BCCR). With THKP, the velocity of a pressure wave (from hot product gases) in the unburned region shows unsteady behavior which is related to the initial porosity or permeability. Simultaneous measurements with pressure gauges and ion gauges reveal that the pressure wave precedes the burn front. Steady burning of BCCR was observed with pressure gauge diagnostics and with a microwave interferometry technique.

  17. Multipole seismoelectric logging while drilling (LWD) for acoustic velocity measurements

    E-Print Network [OSTI]

    Zhu, Zhenya

    2012-01-01

    In seismoelectric well logging, an acoustic wave propagates along a borehole and induces electrical signals along the borehole wall. The apparent velocities of these seismoelectric signals are equal to the formation ...

  18. Seismic velocity and Q anisotropy in fractured poroelastic media

    E-Print Network [OSTI]

    The energy-velocity vector ve of the qP and qSV waves is ..... A., On the spatial variability of parameters of the unsaturated hydraulic conductivity, Water Res.

  19. Extreme wave impinging and overtopping 

    E-Print Network [OSTI]

    Ryu, Yong Uk

    2009-06-02

    This investigates the velocity fields of a plunging breaking wave impinging on a structure through measurements in a two-dimensional wave tank. As the wave breaks and overtops the structure, so-called green water is generated. The flow becomes multi...

  20. 11. Acoustic waves and shocks 11.1 Acoustic waves of low amplitude

    E-Print Network [OSTI]

    Pohl, Martin Karl Wilhelm

    11. Acoustic waves and shocks 11.1 Acoustic waves of low amplitude Let us consider an adiabatic (or velocity of sound waves is constant. Does that still hold for sound waves of finite amplitude? Equation 11. This is the result of the non-linear nature of the hydrodynamical equations. On should note that wave damping, e

  1. Distance Probes of Dark Energy

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

    Kim, A. G.; Padmanabhan, N.; Aldering, G.; Allen, S. W.; Baltay, C.; Cahn, R. N.; D' Andrea, C. B.; Dalal, N.; Dawson, K. S.; Denney, K. D.; et al

    2015-03-15

    We present the results from the Distances subgroup of the Cosmic Frontier Community Planning Study (Snowmass 2013). This document summarizes the current state of the field as well as future prospects and challenges. In addition to the established probes using Type Ia supernovae and baryon acoustic oscillations, we also consider prospective methods based on clusters, active galactic nuclei, gravitational wave sirens and strong lensing time delays.

  2. Universality of the de Broglie-Einstein velocity equation

    E-Print Network [OSTI]

    Yusuf Z. Umul

    2007-12-06

    The de Broglie-Einstein velocity equation is derived for a relativistic particle by using the energy and momentum relations in terms of wave and matter properties. It is shown that the velocity equation is independent from the relativistic effects and is valid also for the non-relativistic case. The results of this property is discussed.

  3. Protective shield for an instrument probe

    DOE Patents [OSTI]

    Johnsen, Howard A.; Ross, James R.; Birtola, Sal R.

    2004-10-26

    A shield is disclosed that is particularly useful for protecting exposed optical elements at the end of optical probes used in the analysis of hazardous emissions in and around an industrial environment from the contaminating effects of those emissions. The instant invention provides a hood or cowl in the shape of a right circular cylinder that can be fitted over the end of such optical probes. The hood provides a clear aperture through which the probe can perform unobstructed analysis. The probe optical elements are protected from the external environment by passing a dry gas through the interior of the hood and out through the hood aperture in sufficient quantity and velocity to prevent any significant mixing between the internal and external environments. Additionally, the hood is provided with a cooling jacket to lessen the potential for damaging the probe due to temperature excursions.

  4. DIFFUSING ACOUSTIC WAVE TRANSPORT AND SPECTROSCOPY

    E-Print Network [OSTI]

    Page, John

    1 Chapter DIFFUSING ACOUSTIC WAVE TRANSPORT AND SPECTROSCOPY J.H. PAGE, M.L. COWAN Dept. of Physics waves, multiple scattering, energy velocity, Diffusing Acoustic Wave Spectroscopy. Abstract the diffusive transport of ultrasonic waves, and then describe a new ultrasonic technique, Diffusing Acoustic

  5. Directed Relativistic Blast Wave

    E-Print Network [OSTI]

    Andrei Gruzinov

    2007-04-23

    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.

  6. Surface wave array tomography in SE Tibet from ambient seismic noise and two-station analysis - II. Crustal and upper-mantle structure

    E-Print Network [OSTI]

    Yao, H; Beghein, C; Van Der Hilst, RD

    2008-01-01

    M.N. , 2006. Constraining P-wave velocity variations in2005. High- resolution surface wave tomography from ambienterror (? v ) of the shear wave speed along five vertical

  7. Projected Constraints on Lorentz-Violating Gravity with Gravitational Waves

    E-Print Network [OSTI]

    Devin Hansen; Nicolas Yunes; Kent Yagi

    2014-12-12

    Gravitational waves are excellent tools to probe the foundations of General Relativity in the strongly dynamical and non-linear regime. One such foundation is Lorentz symmetry, which can be broken in the gravitational sector by the existence of a preferred time direction, and thus, a preferred frame at each spacetime point. This leads to a modification in the orbital decay rate of binary systems, and also in the generation and chirping of their associated gravitational waves. We here study whether waves emitted in the late, quasi-circular inspiral of non-spinning, neutron star binaries can place competitive constraints on two proxies of gravitational Lorentz-violation: Einstein-\\AE{}ther theory and khronometric gravity. We model the waves in the small-coupling (or decoupling) limit and in the post-Newtonian approximation, by perturbatively solving the field equations in small deformations from General Relativity and in the small-velocity/weak-gravity approximation. We assume a gravitational wave consistent with General Relativity has been detected with second- and third-generation, ground-based detectors, and with the proposed space-based mission, DECIGO, with and without coincident electromagnetic counterparts. Without a counterpart, a detection consistent with General Relativity of neutron star binaries can only place competitive constraints on gravitational Lorentz violation when using future, third-generation or space-based instruments. On the other hand, a single counterpart is enough to place constraints that are 10 orders of magnitude more stringent than current binary pulsar bounds, even when using second-generation detectors. This is because Lorentz violation forces the group velocity of gravitational waves to be different from that of light, and this difference can be very accurately constrained with coincident observations.

  8. Chiral Heat Wave and wave mixing in chiral media

    E-Print Network [OSTI]

    Chernodub, M N

    2015-01-01

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

  9. VOLUME 79, NUMBER 17 P H Y S I C A L R E V I E W L E T T E R S 27 OCTOBER 1997 Energy Velocity of Diffusing Waves in Strongly Scattering Media

    E-Print Network [OSTI]

    in the vicinity of Mie resonances as a result of the temporary storage of wave energy inside the scatterer [4 R3T 2N2 2 Department of Physics, The Hong Kong University of Science and Technology, Clear Water Bay

  10. Modified definition of group velocity and electromagnetic energy conservation equation

    E-Print Network [OSTI]

    Changbiao Wang

    2015-05-11

    The classical definition of group velocity has two flaws: (a) the group velocity can be greater than the phase velocity and break Fermat's principle in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; (b) the definition is not consistent with the principle of relativity for a plane wave in a moving isotropic uniform medium. To remove the flaws, a modified definition is proposed. A criterion is set up to identify the justification of group velocity definition. A "superluminal power flow" is constructed to show that the electromagnetic energy conservation equation cannot uniquely define the power flow if the principle of Fermat is not taken into account.

  11. Enhanced four-wave mixing via crossover resonance in cesium vapor

    E-Print Network [OSTI]

    T. Passerat de Silans; C. S. L. Goncalves; D. Felinto; J. W. R. Tabosa

    2011-07-28

    We report on the observation of enhanced four-wave mixing via crossover resonance in a Doppler broadened cesium vapor. Using a single laser frequency, a resonant parametric process in a double-$\\Lambda$ level configuration is directly excited for a specific velocity class. We investigate this process in different saturation regimes and demonstrate the possibility of generating intensity correlation and anti-correlation between the probe and conjugate beams. A simple theoretical model is developed that accounts qualitatively well to the observed results.

  12. The Effect of Point Velocity Probe Size on Groundwater Velocity Estimation in Noncohesive Sediments

    E-Print Network [OSTI]

    Burris, Natalie Lynn

    2014-12-31

    .7 References Alden, A. S. and C. L. Munster. 1997. Field Test of the In Situ Permeable Ground Water Flow Sensor. Ground Water Monitoring & Remediation 17 no. 4: 81-88. Annable, M. D., Hatfield, K., Cho, J., Klammler, H., Parker, B.L., Cherry, J.A., and P.S.C.../Lewis Publishers. Devlin, J.F. and C.D. McElwee. 2007. Effects of Measurement Error on Horizontal Hydraulic Gradient Estimates. Ground Water 45 no. 1:62-73. Devlin, J.F., Tsoflias, G., McGlashan, M., and P. Schillig. 2009. An Inexpensive Multilevel Array...

  13. Simultaneous use of camera and probe diagnostics to unambiguously identify and study the dynamics of multiple underlying instabilities during the route to plasma turbulence

    SciTech Connect (OSTI)

    Thakur, S. C. Tynan, G. R.; Brandt, C.; Cui, L.; Gosselin, J. J.; Light, A.

    2014-11-15

    We use multiple-tip Langmuir probes and fast imaging to unambiguously identify and study the dynamics of underlying instabilities during the controlled route to fully-developed plasma turbulence in a linear magnetized helicon plasma device. Langmuir probes measure radial profiles of electron temperature, plasma density and potential; from which we compute linear growth rates of instabilities, cross-phase between density and potential fluctuations, Reynold's stress, particle flux, vorticity, time-delay estimated velocity, etc. Fast imaging complements the 1D probe measurements by providing temporally and spatially resolved 2D details of plasma structures associated with the instabilities. We find that three radially separated plasma instabilities exist simultaneously. Density gradient driven resistive drift waves propagating in the electron diamagnetic drift direction separate the plasma into an edge region dominated by strong, velocity shear driven Kelvin-Helmholtz instabilities and a central core region which shows coherent Rayleigh-Taylor modes propagating in the ion diamagnetic drift direction. The simultaneous, complementary use of both probes and camera was crucial to identify the instabilities and understand the details of the very rich plasma dynamics.

  14. Traveling-wave photodetector

    DOE Patents [OSTI]

    Hietala, Vincent M. (Placitas, NM); Vawter, Gregory A. (Albuquerque, NM)

    1993-01-01

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size.

  15. Traveling-wave photodetector

    DOE Patents [OSTI]

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

    1993-12-14

    The traveling-wave photodetector of the present invention combines an absorptive optical waveguide and an electrical transmission line, in which optical absorption in the waveguide results in a photocurrent at the electrodes of the electrical transmission line. The optical waveguide and electrical transmission line of the electrically distributed traveling-wave photodetector are designed to achieve matched velocities between the light in the optical waveguide and electrical signal generated on the transmission line. This velocity synchronization provides the traveling-wave photodetector with a large electrical bandwidth and a high quantum efficiency, because of the effective extended volume for optical absorption. The traveling-wave photodetector also provides large power dissipation, because of its large physical size. 4 figures.

  16. Coherent THz electromagnetic radiation emission as a shock wave...

    Office of Scientific and Technical Information (OSTI)

    Coherent THz electromagnetic radiation emission as a shock wave diagnostic and probe of ultrafast phase transformations Citation Details In-Document Search Title: Coherent THz...

  17. Hydrodynamic ultrasonic probe

    DOE Patents [OSTI]

    Day, Robert A. (Livermore, CA); Conti, Armond E. (San Jose, CA)

    1980-01-01

    An improved probe for in-service ultrasonic inspection of long lengths of a workpiece, such as small diameter tubing from the interior. The improved probe utilizes a conventional transducer or transducers configured to inspect the tubing for flaws and/or wall thickness variations. The probe utilizes a hydraulic technique, in place of the conventional mechanical guides or bushings, which allows the probe to move rectilinearly or rotationally while preventing cocking thereof in the tube and provides damping vibration of the probe. The probe thus has lower friction and higher inspection speed than presently known probes.

  18. Developing de Broglie Wave

    E-Print Network [OSTI]

    J X Zheng-Johansson; P-I Johansson

    2006-08-27

    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.

  19. Average Angular Velocity

    E-Print Network [OSTI]

    H. Essen

    2004-01-28

    This paper addresses the problem of the separation of rotational and internal motion. It introduces the concept of average angular velocity as the moment of inertia weighted average of particle angular velocities. It extends and elucidates the concept of Jellinek and Li (1989) of separation of the energy of overall rotation in an arbitrary (non-linear) $N$-particle system. It generalizes the so called Koenig's theorem on the two parts of the kinetic energy (center of mass plus internal) to three parts: center of mass, rotational, plus the remaining internal energy relative to an optimally translating and rotating frame.

  20. Velocity pump reaction turbine

    DOE Patents [OSTI]

    House, Palmer A. (Walnut Creek, CA)

    1984-01-01

    An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

  1. Velocity pump reaction turbine

    DOE Patents [OSTI]

    House, Palmer A. (Walnut Creek, CA)

    1982-01-01

    An expanding hydraulic/two-phase velocity pump reaction turbine including a dual concentric rotor configuration with an inter-rotor annular flow channel in which the inner rotor is mechanically driven by the outer rotor. In another embodiment, the inner rotor is immobilized and provided with gas recovery ports on its outer surface by means of which gas in solution may be recovered. This velocity pump reaction turbine configuration is capable of potential energy conversion efficiencies of up to 70%, and is particularly suited for geothermal applications.

  2. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1988-03-08

    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.

  3. Explosive plane-wave lens

    DOE Patents [OSTI]

    Marsh, S.P.

    1987-03-12

    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.

  4. Tracking deep mantle reservoirs with ultra-low velocity zones Allen K. McNamara a,

    E-Print Network [OSTI]

    Rhoads, James

    Tracking deep mantle reservoirs with ultra-low velocity zones Allen K. McNamara a, , Edward J, that directly overlies the core-mantle boundary (CMB). These regions have been dubbed Ultra-Low Velocity Zones. Introduction For over 15 yrs seismologists have mapped regions of ultra-low P- and S-wave velocities

  5. Wave-Particle Interactions in Electron Acoustic Waves in Pure Ion Plasmas F. Anderegg, C. F. Driscoll, D. H. E. Dubin, and T. M. O'Neil

    E-Print Network [OSTI]

    California at San Diego, University of

    Wave-Particle Interactions in Electron Acoustic Waves in Pure Ion Plasmas F. Anderegg, C. F waves (EAW) with a phase velocity less than twice the plasma thermal velocity are observed on pure ion excitation the EAW is more frequency variable than typical Langmuir waves, and at large excitations resonance

  6. Kinematics of extreme waves in deep water John Grue*, Didier Clamond, Morten Huseby, Atle Jensen

    E-Print Network [OSTI]

    Clamond, Didier

    Kinematics of extreme waves in deep water John Grue*, Didier Clamond, Morten Huseby, Atle Jensen fluid velocity, e ffiffiffiffi g=k p is then defined. Deep water waves with a fluid velocity up to 75 2004 Abstract The velocity profiles under crest of a total of 62 different steep wave events in deep

  7. Seismic velocity estimation from time migration

    E-Print Network [OSTI]

    Cameron, Maria Kourkina

    2007-01-01

    Seismic images . . . . . . . . . . . . . . . . .Algorithms producing the seismic velocities from thethe Dix velocities and the true seismic velocities in 2D . .

  8. 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

    Multicomponent seismic data, combining P-wave and converted P-to-SV wave (C-wave) wavefields (fast and slow) with differing polarization. The 4C, 3D ocean-bottom cable (OBC) multicomponent seismic objectives were to evaluate seismic attributes, such as VP/VS velocity ratios and Poisson's ratio derived

  9. Grading of lumber using stress waves 

    E-Print Network [OSTI]

    Bethi, Rajeshwar

    1994-01-01

    The goal of this research was to develop stress wave grading technology suitable for small lumber mills. Specific goals include: 1) develop an ultrasonic probe configuration to facilitate real-time grain angle and edge knot measurement, 2) determine...

  10. Mechanical probing of liquid foam aging

    E-Print Network [OSTI]

    Isabelle Cantat; Olivier Pitois

    2006-09-19

    We present experimental results on the Stokes experiment performed in a 3D dry liquid foam. The system is used as a rheometric tool : from the force exerted on a 1cm glass bead, plunged at controlled velocity in the foam in a quasi static regime, local foam properties are probed around the sphere. With this original and simple technique, we show the possibility of measuring the foam shear modulus, the gravity drainage rate and the evolution of the bubble size during coarsening.

  11. Discrimination of porosity and fluid saturation using seismic velocity analysis

    DOE Patents [OSTI]

    Berryman, James G. (Danville, CA)

    2001-01-01

    The method of the invention is employed for determining the state of saturation in a subterranean formation using only seismic velocity measurements (e.g., shear and compressional wave velocity data). Seismic velocity data collected from a region of the formation of like solid material properties can provide relatively accurate partial saturation data derived from a well-defined triangle plotted in a (.rho./.mu., .lambda./.mu.)-plane. When the seismic velocity data are collected over a large region of a formation having both like and unlike materials, the method first distinguishes the like materials by initially plotting the seismic velocity data in a (.rho./.lambda., .mu./.lambda.)-plane to determine regions of the formation having like solid material properties and porosity.

  12. Dark Matter Velocity Spectroscopy

    E-Print Network [OSTI]

    Eric G. Speckhard; Kenny C. Y. Ng; John F. Beacom; Ranjan Laha

    2015-07-31

    Dark matter decays or annihilations that produce line-like spectra may be smoking-gun signals. However, even such distinctive signatures can be mimicked by astrophysical or instrumental causes. We show that velocity spectroscopy-the measurement of energy shifts induced by relative motion of source and observer-can separate these three causes with minimal theoretical uncertainties. The principal obstacle has been energy resolution, but upcoming experiments will reach the required 0.1% level. As an example, we show that the imminent Astro-H mission can use Milky Way observations to separate possible causes of the 3.5-keV line. We discuss other applications.

  13. Dispersion relations for acoustic waves in heterogeneous multi-layered structures contacting with

    E-Print Network [OSTI]

    Turova, Varvara

    Dispersion relations for acoustic waves in heterogeneous multi-layered structures contacting application for the computation of the velocity of acoustic waves excited in complicated multi: Multi-layered structures, Surface acoustic waves, Dispersion relations, Homogenization, Biosensor

  14. Solving non-linear equations of longitudinal and transverse electron waves in collisionless Maxwellian plasma

    E-Print Network [OSTI]

    Soshnikov, V N

    2007-01-01

    We have considered an expansion of asymptotical solutions of the non-linearized equations for both longitudinal and transverse waves in collisionless Maxwellian plasma in series of non-damping overtones of the field E(x,t) and electron velocity distribution function f which equals f(0)plus f(1), where f(0) is background Maxwellian distribution function; f(1)is disturbed wave part. There are deduced recurrent relations expressing the terms of higher order by means of the terms of lower orders. There are proposed also procedures of cutting the distribution function to the value f equal zero in the regions where kinetic equation becomes inapplicable due to f becomes negative. There is noted a possibility of experimental probing appearing exotic results.

  15. Electrical resistivity probes

    DOE Patents [OSTI]

    Lee, Ki Ha; Becker, Alex; Faybishenko, Boris A.; Solbau, Ray D.

    2003-10-21

    A miniaturized electrical resistivity (ER) probe based on a known current-voltage (I-V) electrode structure, the Wenner array, is designed for local (point) measurement. A pair of voltage measuring electrodes are positioned between a pair of current carrying electrodes. The electrodes are typically about 1 cm long, separated by 1 cm, so the probe is only about 1 inch long. The electrodes are mounted to a rigid tube with electrical wires in the tube and a sand bag may be placed around the electrodes to protect the electrodes. The probes can be positioned in a borehole or on the surface. The electrodes make contact with the surrounding medium. In a dual mode system, individual probes of a plurality of spaced probes can be used to measure local resistance, i.e. point measurements, but the system can select different probes to make interval measurements between probes and between boreholes.

  16. Resonance Van Hove Singularities in Wave Kinetics

    E-Print Network [OSTI]

    Shi, Yi-Kang

    2015-01-01

    Wave kinetic theory has been developed to describe the statistical dynamics of weakly nonlinear, dispersive waves. However, we show that systems which are generally dispersive can have resonant sets of wave modes with identical group velocities, leading to a local breakdown of dispersivity. This shows up as a geometric singularity of the resonant manifold and possibly as an infinite phase measure in the collision integral. Such singularities occur widely for classical wave systems, including acoustical waves, Rossby waves, helical waves in rotating fluids, light waves in nonlinear optics and also in quantum transport, e.g. kinetics of electron-hole excitations (matter waves) in graphene. These singularities are the exact analogue of the critical points found by Van Hove in 1953 for phonon dispersion relations in crystals. The importance of these singularities in wave kinetics depends on the dimension of phase space $D=(N-2)d$ ($d$ physical space dimension, $N$ the number of waves in resonance) and the degree ...

  17. Impact loads and wave kinematics on a fixed truncated circular cylinder due to nonlinear waves in a 2-D tank 

    E-Print Network [OSTI]

    Zou, Jun

    1995-01-01

    . Simultaneous measurements of the particle velocities under the crest, the wave elevation at the energy concentrated location, the wave elevation on the cylinder surface, dynamic pressure distribution and impact force were performed to study the relationships...

  18. Ion velocities in a micro-cathode arc thruster

    SciTech Connect (OSTI)

    Zhuang Taisen; Shashurin, Alexey; Keidar, Michael; Beilis, Isak

    2012-06-15

    Ion velocities in the plasma jet generated by the micro-cathode arc thruster are studied by means of time-of-flight method using enhanced ion detection system (EIDS). The EIDS triggers perturbations (spikes) on arc current waveform, and the larger current in the spike generates denser plasma bunches propagating along with the mainstream plasma. The EIDS utilizes double electrostatic probes rather than single probes. The average Ti ion velocity is measured to be around 2 Multiplication-Sign 10{sup 4} m/s without a magnetic field. It was found that the application of a magnetic field does not change ion velocities in the interelectrode region while leads to ion acceleration in the free expanding plasma plume by a factor of about 2. Ion velocities of about 3.5 Multiplication-Sign 10{sup 4} m/s were detected for the magnetic field of about 300 mT at distance of about 100-200 mm from the cathode. It is proposed that plasma is accelerated due to Lorentz force. The average thrust is calculated using the ion velocity measurements and the cathode mass consumption rate, and its increase with the magnetic field is demonstrated.

  19. White light velocity interferometer

    DOE Patents [OSTI]

    Erskine, D.J.

    1999-06-08

    The invention is a technique that allows the use of broadband and incoherent illumination. Although denoted white light velocimetry, this principle can be applied to any wave phenomenon. For the first time, powerful, compact or inexpensive sources can be used for remote target velocimetry. These include flash and arc lamps, light from detonations, pulsed lasers, chirped frequency lasers, and lasers operating simultaneously in several wavelengths. The technique is demonstrated with white light from an incandescent source to measure a target moving at 16 m/s. 41 figs.

  20. Wave merging mechanism: formation of low-frequency Alfven and magnetosonic waves in cosmic plasmas

    SciTech Connect (OSTI)

    Tishchenko, V N; Shaikhislamov, I F

    2014-02-28

    We investigate the merging mechanism for the waves produced by a pulsating cosmic plasma source. A model with a separate background/source description is used in our calculations. The mechanism was shown to operate both for strong and weak source – background interactions. We revealed the effect of merging of individual Alfven waves into a narrow low-frequency wave, whose amplitude is maximal for a plasma expansion velocity equal to 0.5 – 1 of the Alfven Mach number. This wave is followed along the field by a narrow low-frequency magnetosonic wave, which contains the bulk of source energy. For low expansion velocities the wave contains background and source particles, but for high velocities it contains only the background particles. The wave lengths are much greater than their transverse dimension. (letters)

  1. Nonlinear three-wave interaction in marine sediments

    E-Print Network [OSTI]

    Pushkina, N I

    2015-01-01

    Nonlinear interaction of three acoustic waves in a sandy sediment is studied in the frequency range where there is a considerable wave velocity dispersion. The possibility of an experimental observation of the generation of a sound wave by two pump waves propagating at an angle to each other is estimated.

  2. Nonlinear three-wave interaction in marine sediments

    E-Print Network [OSTI]

    N. I. Pushkina

    2015-03-18

    Nonlinear interaction of three acoustic waves in a sandy sediment is studied in the frequency range where there is a considerable wave velocity dispersion. The possibility of an experimental observation of the generation of a sound wave by two pump waves propagating at an angle to each other is estimated.

  3. An electromagnetic analog of gravitational wave memory

    E-Print Network [OSTI]

    Lydia Bieri; David Garfinkle

    2013-09-10

    We present an electromagnetic analog of gravitational wave memory. That is, we consider what change has occurred to a detector of electromagnetic radiation after the wave has passed. Rather than a distortion in the detector, as occurs in the gravitational wave case, we find a residual velocity (a "kick") to the charges in the detector. In analogy with the two types of gravitational wave memory ("ordinary" and "nonlinear") we find two types of electromagnetic kick.

  4. Unitaxial constant velocity microactuator

    DOE Patents [OSTI]

    McIntyre, Timothy J. (Knoxville, TN)

    1994-01-01

    A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-manometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment.

  5. Unitaxial constant velocity microactuator

    DOE Patents [OSTI]

    McIntyre, T.J.

    1994-06-07

    A uniaxial drive system or microactuator capable of operating in an ultra-high vacuum environment is disclosed. The mechanism includes a flexible coupling having a bore therethrough, and two clamp/pusher assemblies mounted in axial ends of the coupling. The clamp/pusher assemblies are energized by voltage-operated piezoelectrics therewithin to operatively engage the shaft and coupling causing the shaft to move along its rotational axis through the bore. The microactuator is capable of repeatably positioning to sub-nanometer accuracy while affording a scan range in excess of 5 centimeters. Moreover, the microactuator generates smooth, constant velocity motion profiles while producing a drive thrust of greater than 10 pounds. The system is remotely controlled and piezoelectrically driven, hence minimal thermal loading, vibrational excitation, or outgassing is introduced to the operating environment. 10 figs.

  6. Development of neural network calibration algorithms for multi-port pressure probes 

    E-Print Network [OSTI]

    Kinser Robert Eric

    1996-01-01

    mini-5-hole probe having a diameter of only 0.065" is calibrated and used to measure three dimensional velocity data about a delta wing model to demonstrate PROBENET's real world application....

  7. Thermoplastic waves in magnetars

    E-Print Network [OSTI]

    Beloborodov, Andrei M

    2014-01-01

    Magnetar activity is generated by shear motions of the neutron star surface, which relieve internal magnetic stresses. An analogy with earthquakes and faults is problematic, as the crust is permeated by strong magnetic fields, which greatly constrain crustal displacements. We describe a new deformation mechanism that is specific to strongly magnetized neutron stars. The magnetically stressed crust begins to move because of a thermoplastic instability, which launches a wave that shears the crust and burns its magnetic energy. The propagating wave front resembles the deflagration front in combustion physics. We describe the conditions for the instability, the front structure and velocity, and discuss implications for observed magnetar activity.

  8. Local tunneling characteristics near a grain boundary of a d-wave superconductor as probed by a normal-metal or a low-T-c-superconductor STM tip 

    E-Print Network [OSTI]

    Zhao, HW; Hu, Chia-Ren.

    2000-01-01

    We study the local single-particle tunneling characteristics [as observed with scanning tunnel microscopy (STM)] for N-D and S-D tunneling, where D is a d-wave superconductor with a {100}{110} grain boundary. The tunneling Hamiltonian method is used...

  9. Backreacting p-wave Superconductors

    E-Print Network [OSTI]

    Raúl E. Arias; Ignacio Salazar Landea

    2013-01-28

    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.

  10. Critical regimes of internal gravity wave generation

    E-Print Network [OSTI]

    Vitaly V. Bulatov; Yuriy V. Vladimirov; Vasily A. Vakorin

    2005-11-27

    The problem of constructing an asymptotic representation of the solution of the internal gravity wave field exited by a source moving at a velocity close to the maximum group velocity of the individual wave mode is considered. For the critical regimes of individual mode generation the asymptotic representation of the solution obtained is expressed in terms of a zero-order Macdonald function. The results of numerical calculations based on the exact and asymptotic formulas are given.

  11. Ponderomotive Forces On Waves In Modulated Media

    SciTech Connect (OSTI)

    Dodin, I.Y; Fisch, Nathaniel

    2014-02-28

    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.

  12. Measurement of turbulent wind velocities using a rotating boom apparatus

    SciTech Connect (OSTI)

    Sandborn, V.A.; Connell, J.R.

    1984-04-01

    The present report covers both the development of a rotating-boom facility and the evaluation of the spectral energy of the turbulence measured relative to the rotating boom. The rotating boom is composed of a helicopter blade driven through a pulley speed reducer by a variable speed motor. The boom is mounted on a semiportable tower that can be raised to provide various ratios of hub height to rotor diameter. The boom can be mounted to rotate in either the vertical or horizontal plane. Probes that measure the three components of turbulence can be mounted at any location along the radius of the boom. Special hot-film sensors measured two components of the turbulence at a point directly in front of the rotating blade. By using the probe rotated 90/sup 0/ about its axis, the third turbulent velocity component was measured. Evaluation of the spectral energy distributions for the three components of velocity indicates a large concentration of energy at the rotational frequency. At frequencies slightly below the rotational frequency, the spectral energy is greatly reduced over that measured for the nonrotating case measurements. Peaks in the energy at frequencies that are multiples of the rotation frequency were also observed. We conclude that the rotating boom apparatus is suitable and ready to be used in experiments for developing and testing sensors for rotational measurement of wind velocity from wind turbine rotors. It also can be used to accurately measure turbulent wind for testing theories of rotationally sampled wind velocity.

  13. Onset of Wave Drag due to Generation of Capillary-Gravity Waves by a Moving Object as a Critical Phenomenon

    E-Print Network [OSTI]

    Teodor Burghelea; Victor Steinberg

    2001-04-21

    The onset of the {\\em wave resistance}, via generation of capillary gravity waves, of a small object moving with velocity $V$, is investigated experimentally. Due to the existence of a minimum phase velocity $V_c$ for surface waves, the problem is similar to the generation of rotons in superfluid helium near their minimum. In both cases waves or rotons are produced at $V>V_c$ due to {\\em Cherenkov radiation}. We find that the transition to the wave drag state is continuous: in the vicinity of the bifurcation the wave resistance force is proportional to $\\sqrt{V-V_c}$ for various fluids.

  14. Wave Motion

    E-Print Network [OSTI]

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

  15. Pore fluid effects on seismic velocity in anisotropic rocks

    SciTech Connect (OSTI)

    Mukerji, T.; Mavko, G. (Stanford Univ., CA (United States). Dept. of Geophysics)

    1994-02-01

    A simple new technique predicts the high- and low-frequency saturated velocities in anisotropic rocks entirely in terms of measurable dry rock properties without the need for idealized crack geometries. Measurements of dry velocity versus pressure and porosity versus pressure contain all of the necessary information for predicting the frequency-dependent effects of fluid saturation. Furthermore, these measurements automatically incorporate all pore interaction, so there is no limitation to low crack density. The velocities are found to depend on five key interrelated variables: frequency, the distribution of compliant crack-like porosity, the intrinsic or noncrack anisotropy, fluid viscosity and compressibility, and effective pressure. The sensitivity of velocities to saturation is generally greater at high frequencies than low frequencies. The magnitude of the differences from dry to saturated and from low frequency to high frequency is determined by the compliant or crack-like porosity. Predictions of saturated velocities based on dry data for sandstone and granite show that compressional velocities generally increase with saturation and with frequency. However, the degree of compressional wave anisotropy may either increase or decrease upon saturation depending on the crack distribution, the effective pressure, and the frequency at which the measurements are made. Shear-wave velocities can either increase or decrease with saturation, and the degree of anisotropy depends on the microstructure, pressure, and frequency. Consequently great care must be taken when interpreting observed velocity anisotropy for measurements at low frequencies, typical of in situ observations, will generally be different from those at high frequencies, typical of the laboratory.

  16. Development of a thermoacoustic travelling-wave refrigerator

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    mean pressure. By that way, conduction losses on the cold heat exchanger are minimized. However to an acoustic wave. Thereby, gas particle pressure and velocity oscillate around a mean value. According of a travelling-wave, acoustic pressure and velocity are in phase inducing a Stirling type cycle. Over an acoustic

  17. Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor of

    E-Print Network [OSTI]

    Cerveny, Vlastislav

    Kirchhoff prestack depth migration in velocity models with and without rotation of the tensor-mail: bucha@seis.karlov.mff.cuni.cz Summary We use the Kirchhoff prestack depth migration to calculate is limited to P-waves. Keywords 3-D Kirchhoff prestack depth migration, anisotropic velocity model, rotation

  18. Inversion Of Travel Time For Velocity

    E-Print Network [OSTI]

    Willis, M.E.

    1983-01-01

    Common source velocities and borehole compensated (BC) estimates have been used to obtain formation velocity estimates from full waveform acoustic

  19. Numerical Simulation of Fault Zone Guided Waves: Accuracy and 3-D Effects

    E-Print Network [OSTI]

    Ben-Zion, Yehuda

    seismic velocity. When sources are located in or close to these low-velocity zones, guided seismic head for seismic fault zone head and trapped waves. Fault zone head waves propagate along material discontinuity Pure and Applied Geophysics #12;traveling inside low velocity fault zone layers with dispersive

  20. Chemical Wave Packet Propagation, Reflection, and Spreading Lingfa Yang and Irving R. Epstein*

    E-Print Network [OSTI]

    Epstein, Irving R.

    or away from an initiating perturbation, are found in a reaction-diffusion model with a finite wave. The phase velocity, group velocity, and spreading velocity calculated by linear stability analysis packets in reaction-diffusion systems are rarely seen, even though wave packets have been intensively

  1. Converted wave imaging in anisotropic media using sea-floor seismic data 

    E-Print Network [OSTI]

    Mancini, Fabio

    velocity ratio is derived conventionally by event matching in the P-wave and converted wave stacks. I present an attempt to use well-log derived velocity ratios to avoid this interpretative step. The velocity ratio derived from 4C seismic data is about 30...

  2. Carbon nanotube based electromechanical probes

    E-Print Network [OSTI]

    Yaglioglu, Onnik, 1976-

    2007-01-01

    Electromechanical probing applications continuously require smaller pitches, faster manufacturing and lower electrical resistance. Conventional techniques, such as MEMS based cantilever probes have their shortcomings in ...

  3. Optical Generation of Gigahertz-Frequency Shear Acoustic Waves in Liquid Glycerol

    E-Print Network [OSTI]

    Andrieu, S.

    Picosecond laser ultrasonic techniques for acoustic wave generation and detection have been employed to probe shear acoustic waves in liquid glycerol at gigahertz frequencies. The experimental approach uses a unique laser ...

  4. Correlated noise in networks of gravitational-wave detectors: Subtraction and mitigation

    E-Print Network [OSTI]

    Christensen, Nelson

    of gravitational-wave detectors [22­25] will probe gravitational-wave energy density several orders of magnitude of Technology, Pasadena, California 91125, USA 2 Physics and Astronomy, Carleton College, Northfield, Minnesota

  5. Foldable polymers as probes

    DOE Patents [OSTI]

    Li, Alexander D. Q. (Pullman, WA); Wang, Wei (Pullman, WA)

    2007-07-03

    Disclosed herein are novel probes, which can be used to detect and identify target molecules of interest in a sample. The disclosed probes can be used to monitor conformational changes induced by molecular recognition events in addition to providing signaling the presence and/or identity of a target molecule. Methods, including solid phase synthesis techniques, for making probe molecules that exhibit changes in their optical properties upon target molecule binding are described in the disclosure. Also disclosed herein are novel chromophore moieties, which have tailored fluorescent emission spectra.

  6. Chemical sensing flow probe

    DOE Patents [OSTI]

    Laguna, G.R.; Peter, F.J.; Butler, M.A.

    1999-02-16

    A new chemical probe determines the properties of an analyte using the light absorption of the products of a reagent/analyte reaction. The probe places a small reaction volume in contact with a large analyte volume. Analyte diffuses into the reaction volume. Reagent is selectively supplied to the reaction volume. The light absorption of the reaction in the reaction volume indicates properties of the original analyte. The probe is suitable for repeated use in remote or hostile environments. It does not require physical sampling of the analyte or result in significant regent contamination of the analyte reservoir. 7 figs.

  7. Chemical sensing flow probe

    DOE Patents [OSTI]

    Laguna, George R. (Albuquerque, NM); Peter, Frank J. (Albuquerque, NM); Butler, Michael A. (Albuquerque, NM)

    1999-01-01

    A new chemical probe determines the properties of an analyte using the light absorption of the products of a reagent/analyte reaction. The probe places a small reaction volume in contact with a large analyte volume. Analyte diffuses into the reaction volume. Reagent is selectively supplied to the reaction volume. The light absorption of the reaction in the reaction volume indicates properties of the original analyte. The probe is suitable for repeated use in remote or hostile environments. It does not require physical sampling of the analyte or result in significant regent contamination of the analyte reservoir.

  8. High Order Hybrid Numerical Simulations of Two Dimensional Detonation Waves

    E-Print Network [OSTI]

    Cai, Wei

    reaction time U1 = t + ux + vy contravariant velocity U2 = t + ux + vy contravariant velocity a0 = local. The detonation waves are assumed to un- dergo an irreversible, unimolecular reaction A B. Several cases T = temperature T = v u U = conservative variables in curvilinear (, ) coordinates 2 #12;u = flow x- velocity u

  9. Velocity oscillations in the outer heliosphere: A signature of pickup ion temperature variability?

    E-Print Network [OSTI]

    Richardson, John

    unusual long-wavelength, low- frequency velocity oscillations in the solar wind with periods of $2.3 daysÃ?1 and characteristic length scales that range from 0.5 to 1 AU. The amplitudes of the waves these waves are seen can be attributed to their unusually long wavelength, since the only sources capable

  10. A Bragg grating on LiNbO? waveguide for velocity-matching of electrooptic modulators 

    E-Print Network [OSTI]

    Wang, Ruiyu

    2001-01-01

    An experimental study of the fabrication of a surface grating in a TiO? film on a LiNbO? substrate is described. Such a grating can be used to achieve velocity-matching between an optical wave and a RF signal in a slow-wave modulator structure. A 1...

  11. Imaging seismic velocity structure beneath the Iceland hot spot: A finite frequency approach

    E-Print Network [OSTI]

    Shen, Yang

    Imaging seismic velocity structure beneath the Iceland hot spot: A finite frequency approach Shu and S wave speeds extending from shallow mantle to 400 km depth beneath Iceland. In reality, seismic waves anomaly beneath Iceland and its geodynamic implications. We developed a tomographic method that utilizes

  12. Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen

    E-Print Network [OSTI]

    Louis, Sushil J.

    Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Genetic Adaptive­surface models from seismic travel­time data. Given a sub­surface model, the physics of wave propagation through refractive media can be used to compute travel times for seismic waves. How­ ever, in practice, we have

  13. P wave velocity variations in the Coso region, California, derived...

    Open Energy Info (EERE)

    for station elevation, weighted, and back-projected along their ray paths through models defined with layers of blocks. Slowness variations in the surface layer reflect...

  14. Longshore sediment transport rate calculated incorporating wave orbital velocity fluctuations 

    E-Print Network [OSTI]

    Smith, Ernest Ray

    2006-10-30

    Laboratory experiments were performed to study and improve longshore sediment transport rate predictions. Measured total longshore transport in the laboratory was approximately three times greater for plunging breakers ...

  15. Fermi velocity renormalization and dynamical gap generation in graphene

    E-Print Network [OSTI]

    C. Popovici; C. S. Fischer; L. von Smekal

    2015-01-12

    We study the renormalization of the Fermi velocity by the long-range Coulomb interactions between the charge carriers in the Dirac-cone approximation for the effective low-energy description of the electronic excitations in graphene at half filling. Solving the coupled system of Dyson-Schwinger equations for the dressing functions in the corresponding fermion propagator with various approximations for the particle-hole polarization we observe that Fermi velocity renormalization effects generally lead to a considerable increase of the critical coupling for dynamical gap generation and charge-density wave formation at the semimetal-insulator transition.

  16. Geometric phases of water waves

    E-Print Network [OSTI]

    Francesco Fedele

    2014-08-08

    Recently, Banner et al. (2014) highlighted a new fundamental property of open ocean wave groups, the so-called crest slowdown. For linear narrowband waves, this is related to the geometric and dynamical phase velocities $U_d$ and $U_g$ associated with the parallel transport through the principal fiber bundle of the wave motion with $\\mathit{U}(1)$ symmetry. The theoretical predictions are shown to be in fair agreement with ocean field observations, from which the average crest speed $c=U_d+U_g$ with $c/U_d\\approx0.8$ and $U_{g}/U_d\\approx-0.2$.

  17. Fiber inspired neural probes

    E-Print Network [OSTI]

    Canales, Andrés

    2013-01-01

    Limitations in the currently available technology for neural probes impede our progress towards a comprehensive brain activity map. The lack of understanding the brain function leads to limited options for the treatment ...

  18. The various manifestations of collisionless dissipation in wave propagation

    SciTech Connect (OSTI)

    Benisti, Didier; Morice, Olivier; Gremillet, Laurent

    2012-06-15

    The propagation of an electrostatic wave packet inside a collisionless and initially Maxwellian plasma is always dissipative because of the irreversible acceleration of the electrons by the wave. Then, in the linear regime, the wave packet is Landau damped, so that in the reference frame moving at the group velocity, the wave amplitude decays exponentially with time. In the nonlinear regime, once phase mixing has occurred and when the electron motion is nearly adiabatic, the damping rate is strongly reduced compared to the Landau one, so that the wave amplitude remains nearly constant along the characteristics. Yet, we show here that the electrons are still globally accelerated by the wave packet, and in one dimension, this leads to a non local amplitude dependence of the group velocity. As a result, a freely propagating wave packet would shrink, and therefore, so would its total energy. In more than one dimension, not only does the magnitude of the group velocity nonlinearly vary, but also its direction. In the weakly nonlinear regime, when the collisionless damping rate is still significant compared to its linear value, the group velocity is directed towards the outside of the wave packet and tends to increase its transverse extent, while the opposite is true once the wave is essentially undamped. The impact of the nonlinear variation of the group velocity on the transverse size of the wave packet is quantified, and compared to that induced by the self-focussing due to wave front bowing.

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

    E-Print Network [OSTI]

    Michael R. Collier; Aaron Roberts; Adolfo Vinas

    2007-10-20

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

  20. Direct Vlasov simulations of electron-attracting cylindrical Langmuir probes in flowing plasmas

    SciTech Connect (OSTI)

    Sánchez-Arriaga, G.; Pastor-Moreno, D.

    2014-07-15

    Current collection by positively polarized cylindrical Langmuir probes immersed in flowing plasmas is analyzed using a non-stationary direct Vlasov-Poisson code. A detailed description of plasma density spatial structure as a function of the probe-to-plasma relative velocity U is presented. Within the considered parametric domain, the well-known electron density maximum close to the probe is weakly affected by U. However, in the probe wake side, the electron density minimum becomes deeper as U increases and a rarified plasma region appears. Sheath radius is larger at the wake than at the front side. Electron and ion distribution functions show specific features that are the signature of probe motion. In particular, the ion distribution function at the probe front side exhibits a filament with positive radial velocity. It corresponds to a population of rammed ions that were reflected by the electric field close to the positively biased probe. Numerical simulations reveal that two populations of trapped electrons exist: one orbiting around the probe and the other with trajectories confined at the probe front side. The latter helps to neutralize the reflected ions, thus explaining a paradox in past probe theory.

  1. Model for resonant plasma probe.

    SciTech Connect (OSTI)

    Warne, Larry Kevin; Johnson, William Arthur; Hebner, Gregory Albert; Jorgenson, Roy E.; Coats, Rebecca Sue

    2007-04-01

    This report constructs simple circuit models for a hairpin shaped resonant plasma probe. Effects of the plasma sheath region surrounding the wires making up the probe are determined. Electromagnetic simulations of the probe are compared to the circuit model results. The perturbing effects of the disc cavity in which the probe operates are also found.

  2. Velocity and attenuation in partially molten rocks

    SciTech Connect (OSTI)

    Mavko, G.M.

    1980-10-10

    Interpretation of seismic velocity and attenuation in partially molten rocks has been limited, with few exceptions, to models that assume the melt to be distributed either as spheres or as thin films. However, other melt phase geometries, such as interconnected tubes along grain edges, might equally well account for seismic observations if there is a much larger fraction of melt. Seismic velocity and attenuation are estimated in rocks in which the melt phase has the tube geometry, and the results are compared with results expected for the more familiar film model under similar conditions. For a given melt fraction, tubes are found to give moduli intermediate between moduli for rigid spherical inclusions and compliant films. For example, in polycrystalline olivine at 20 kbar the model predicts a decrease in V/sub s/ of 10% and a decrease in V/sub p/ of 5% at 0.05 melt fraction, without considering inelastic relaxation. Shear attenuation appears to be dominated by viscous flow of melt between the tubes and/or films. For olivine the tube model predicts the increment of relaxation due to melt, ..delta mu../..mu.., to be 0.01 at 0.05 melt fraction. Relaxation of the bulk modulus is dominated by flow between melt pockets of different shape, heat flow, and solid-melt phase change. If melt is present, considerable bulk attenuation is expected, although the relaxation may be observable only at long periods, outside the seismic body wave band.

  3. MACCS2/Deposition Velocity Workshop

    Office of Energy Efficiency and Renewable Energy (EERE)

    The Department of Energy’s Chief of Nuclear Safety hosted a MACCS2/Deposition Velocity Workshop on June 5-6, 2012, in Germantown, Maryland. Approximately 70 participants attended. The purpose of...

  4. Surface plasmon standing waves on Ag nanorods: observations of finite size effects and size dependency

    E-Print Network [OSTI]

    Dunin-Borkowski, Rafal E.

    Surface plasmon standing waves on Ag nanorods: observations of finite size effects and size to have clear configuration of standing waves of the nanorod. The nm resolution of the electron probe standing wave on a string with fixed ends, we observed that the wavelength of the SP standing wave

  5. New insights on boundary plasma turbulence and the quasi-coherent mode in Alcator C-Mod using a Mirror Langmuir Probe

    SciTech Connect (OSTI)

    LaBombard, B.; Golfinopoulos, T.; Terry, J. L.; Brunner, D.; Davis, E.; Greenwald, M.; Hughes, J. W. [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)] [MIT Plasma Science and Fusion Center, Cambridge, Massachusetts 02139 (United States)

    2014-05-15

    A new “Mirror Langmuir Probe” diagnostic, combined with a double-coil scanning magnetic probe, is used to interrogate Alcator C-Mod's quasi-coherent mode (QCM) with unprecedented detail. In ohmic EDA H-modes, the QCM is found to reside in a region of positive radial electric field, with a radial width (?3?mm) that spans open and closed field line regions. Large amplitude, in-phase sinusoidal bursts (?100?kHz) in density, electron temperature, and plasma potential are observed, with potential lagging density by ?16°, producing an outward radial transport velocity of ?10?m/s. Mode propagation corresponds to the sum of local E × B and electron diamagnetic drift velocities. Poloidal magnetic field fluctuations project to current filaments carrying peak current densities of ?25 A/cm{sup 2}. An evaluation of parallel electron force balance (Ohm's law) over a fluctuation cycle indicates a significant electromotive component. Interchange drive is also a contributor in the current continuity (vorticity) equation. Thus, the QCM is primarily a separatrix-spanning electron drift-wave with interchange and electromagnetic contributions.

  6. Trapping and Frequency Variability in Electron Acoustic Waves

    E-Print Network [OSTI]

    California at San Diego, University of

    Trapping and Frequency Variability in Electron Acoustic Waves C.F. Driscoll, F. Anderegg, D 92093 USA Abstract. Electron Acoustic Waves (EAWs) with a phase velocity less than twice the plasma. Keywords: add some here PACS: 52.27.Jt, 52.35.Fp, 52.35.Sb Electron Acoustic Waves (EAWs) are the low

  7. Diffusing acoustic wave spectroscopy M. L. Cowan,1

    E-Print Network [OSTI]

    Page, John

    Diffusing acoustic wave spectroscopy M. L. Cowan,1 I. P. Jones,1, * J. H. Page,1,2, and D. A. Weitz called diffusing acoustic wave spec- troscopy DAWS . In this technique, the motion of the scatterers e the particle velocity correlation function. Potential appli- cations of diffusing acoustic wave spectroscopy

  8. Development of an acoustic wave sensor for biological

    E-Print Network [OSTI]

    Turova, Varvara

    -Jacobi equation can be rewritten as or Application to the propagation of surface acoustic waves Velocity contour . Comparison with the eikonal equation yields the condition Acoustic waves in anisotropic crystals obeyMotivation Development of an acoustic wave sensor for biological and medical applications

  9. Inwardly Rotating Spiral Waves in a Reaction-Diffusion System

    E-Print Network [OSTI]

    Epstein, Irving R.

    in an autocatalytic reaction. The local curvature near the open wave ends is high, making the velocity of the endInwardly Rotating Spiral Waves in a Reaction-Diffusion System Vladimir K. Vanag and Irving R in the spatially extended Belousov-Zhabotinsky (BZ) reaction. Since then, rotating spirals and target waves have

  10. Convective heat flow probe

    DOE Patents [OSTI]

    Dunn, J.C.; Hardee, H.C.; Striker, R.P.

    1984-01-09

    A convective heat flow probe device is provided which measures heat flow and fluid flow magnitude in the formation surrounding a borehole. The probe comprises an elongate housing adapted to be lowered down into the borehole; a plurality of heaters extending along the probe for heating the formation surrounding the borehole; a plurality of temperature sensors arranged around the periphery of the probe for measuring the temperature of the surrounding formation after heating thereof by the heater elements. The temperature sensors and heater elements are mounted in a plurality of separate heater pads which are supported by the housing and which are adapted to be radially expanded into firm engagement with the walls of the borehole. The heat supplied by the heater elements and the temperatures measured by the temperature sensors are monitored and used in providing the desired measurements. The outer peripheral surfaces of the heater pads are configured as segments of a cylinder and form a full cylinder when taken together. A plurality of temperature sensors are located on each pad so as to extend along the length and across the width thereof, with a heating element being located in each pad beneath the temperature sensors. An expansion mechanism driven by a clamping motor provides expansion and retraction of the heater pads and expandable packet-type seals are provided along the probe above and below the heater pads.

  11. EUV detection of high-frequency surface acoustic waves

    E-Print Network [OSTI]

    Siemens, Mark

    We use coherent extreme ultraviolet radiation to probe surface acoustic wave propagation in nickel-on-sapphire nanostructures. We observe no acoustic dispersion over SAW wavelengths down to 200 nm, meaning the SAW propagation ...

  12. Techniques for improving the readout sensitivity of gravitational wave antennae

    E-Print Network [OSTI]

    Smith-Lefebvre, Nicolás de Mateo

    2012-01-01

    The detection of gravitational waves (GWs) from astrophysical sources shows promise as a new method to probe extremely energetic phenomena and test the strong field limit of the general theory of relativity. The era of the ...

  13. Multispectral imaging probe

    DOE Patents [OSTI]

    Sandison, D.R.; Platzbecker, M.R.; Descour, M.R.; Armour, D.L.; Craig, M.J.; Richards-Kortum, R.

    1999-07-27

    A multispectral imaging probe delivers a range of wavelengths of excitation light to a target and collects a range of expressed light wavelengths. The multispectral imaging probe is adapted for mobile use and use in confined spaces, and is sealed against the effects of hostile environments. The multispectral imaging probe comprises a housing that defines a sealed volume that is substantially sealed from the surrounding environment. A beam splitting device mounts within the sealed volume. Excitation light is directed to the beam splitting device, which directs the excitation light to a target. Expressed light from the target reaches the beam splitting device along a path coaxial with the path traveled by the excitation light from the beam splitting device to the target. The beam splitting device directs expressed light to a collection subsystem for delivery to a detector. 8 figs.

  14. Velocity requirements for causality violation

    E-Print Network [OSTI]

    Giovanni Modanese

    2015-01-18

    We re-examine the "Regge-Tolman paradox" with reference to some recent experimental results. It is straightforward to find a formula for the velocity v of the moving system required to produce causality violation. This formula typically yields a velocity very close to the speed of light (for instance, v/c > 0.97 for X-shaped microwaves), which raises some doubts about the real physical observability of the violations. We then compute the velocity requirement introducing a delay between the reception of the primary signal and the emission of the secondary. It turns out that in principle for any delay it is possible to find moving observers able to produce active causal violation. This is mathematically due to the singularity of the Lorentz transformations for beta to 1. For a realistic delay due to the propagation of a luminal precursor, we find that causality violations in the reported experiments are still more unlikely (v/c > 0.989), and even in the hypothesis that the superluminal propagation velocity goes to infinity, the velocity requirement is bounded by v/c > 0.62. We also prove that if two macroscopic bodies exchange energy and momentum through superluminal signals, then the swap of signal source and target is incompatible with the Lorentz transformations; therefore it is not possible to distinguish between source and target, even with reference to a definite reference frame.

  15. Probing metal solidification nondestructively

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration wouldMass mapSpeedingProgramExemptions | National NuclearProbingProbing metal solidification

  16. Probing Mercury's Partnering Preferences

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) by Carbon-Rich Matrices inPrincipalFirm Exchange . . . . .ProbingProbing

  17. Derivation of transformation equations for the parameters that characterize a plane acoustic wave without using phase invariance and Lorentz-Einstein transformation

    E-Print Network [OSTI]

    Bernhard Rothenstein

    2005-06-20

    We show that the transformation equations for the parameters that characterize a plane acoustic wave: period, (frequency), wave vector, wave length and phase velocity can be derived without using phase invariance and Lorentz-Einstein transformation

  18. Quantitative imaging of the air-water flow fields formed by unsteady breaking waves

    E-Print Network [OSTI]

    Belden, Jesse (Jesse Levi)

    2009-01-01

    An experimental method for simultaneously measuring the velocity fields on the air and water side of unsteady breaking waves is presented. The method is applied to breaking waves to investigate the physics of the air and ...

  19. Relevant material we learned in class... Dispersion relation of deep water waves

    E-Print Network [OSTI]

    Budker, Dmitry

    #12;#12;Outline Relevant material we learned in class... Dispersion relation of deep water waves is stationary with respect to: Time k 2 = gk #12;Deep water waves Dispersion relation Phase velocity

  20. Characterization of the alumina-zirconia ceramic system by ultrasonic velocity measurements

    SciTech Connect (OSTI)

    Carreon, Hector; Ruiz, Alberto; Medina, Ariosto; Barrera, Gerardo; Zarate, Juan

    2009-08-15

    In this work an alumina-zirconia ceramic composites have been prepared with {alpha}-Al{sub 2}O{sub 3} contents from 10 to 95 wt.%. The alumina-zirconia ceramic system was characterized by means of precise ultrasonic velocity measurements. In order to find out the factors affecting the variation in wave velocity, the ceramic composite have been examined by X-ray diffraction (XRD) and (SEM) scanning electron microscopy. It was found that the ultrasonic velocity measurements changed considerably with respect to the ceramic composite composition. In particular, we studied the behavior of the physical material property hardness, an important parameter of the ceramic composite mechanical properties, with respect to the variation in the longitudinal and shear wave velocities. Shear wave velocities exhibited a stronger interaction with microstructural and sub-structural features as compared to that of longitudinal waves. In particular, this phenomena was observed for the highest {alpha}-Al{sub 2}O{sub 3} content composite. Interestingly, an excellent correlation between ultrasonic velocity measurements and ceramic composite hardness was observed.

  1. Velocity fluctuations of fission fragments

    E-Print Network [OSTI]

    Felipe J. Llanes-Estrada; Belen Martinez Carmona; Jose L. Muñoz Martinez

    2015-11-19

    We propose event by event velocity fluctuations of nuclear fission fragments as an additional interesting observable that gives access to the nuclear temperature in an independent way from spectral measurements and relates the diffusion and friction coefficients for the relative fragment coordinate in Kramer-like models (in which some aspects of fission can be understood as the diffusion of a collective variable through a potential barrier). We point out that neutron emission by the heavy fragments can be treated in effective theory if corrections to the velocity distribution are needed.

  2. Velocity fluctuations of fission fragments

    E-Print Network [OSTI]

    Llanes-Estrada, Felipe J; Martinez, Jose L Muñoz

    2015-01-01

    We propose event by event velocity fluctuations of nuclear fission fragments as an additional interesting observable that gives access to the nuclear temperature in an independent way from spectral measurements and relates the diffusion and friction coefficients for the relative fragment coordinate in Kramer-like models (in which some aspects of fission can be understood as the diffusion of a collective variable through a potential barrier). We point out that neutron emission by the heavy fragments can be treated in effective theory if corrections to the velocity distribution are needed.

  3. Probing the Ionosphere with the LWA by Rapid Cycling of Celestial Radio Emitters

    E-Print Network [OSTI]

    Ellingson, Steven W.

    large phase distortions to incoming low-frequency radio waves. This presents both a challenge in the ionosphere cause a phase delay to incoming radio waves which is proportional to the TEC along the lineProbing the Ionosphere with the LWA by Rapid Cycling of Celestial Radio Emitters Aaron Cohen (NRL

  4. Time-reversal and Interferometry with applications to forward modeling of wave propagation and a chapter on receiver functions 

    E-Print Network [OSTI]

    van Manen, Dirk-Jan

    2006-01-01

    In exploration seismics and non-destructive evaluation, acoustic, elastic and electro-magnetic waves sensitive to inhomogeneities in the medium under investigation are used to probe its interior. Waves multiply scattered ...

  5. Ultrasonic search wheel probe

    DOE Patents [OSTI]

    Mikesell, Charles R. (Idaho Falls, ID)

    1978-01-01

    A device is provided for reducing internal reflections from the tire of an ultrasonic search wheel probe or from within the material being examined. The device includes a liner with an anechoic chamber within which is an ultrasonic transducer. The liner is positioned within the wheel and includes an aperture through which the ultrasonic sound from the transducer is directed.

  6. Nonlinear Hysteretic Torsional Waves

    E-Print Network [OSTI]

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

    2015-01-09

    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. Wave represents displacement Wave represents pressure Source -Sound Waves

    E-Print Network [OSTI]

    Colorado at Boulder, University of

    is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio. The Sound Waves simulation becomes the source of an analogical mapping to Radio Waves. Concepts Radio Waves 1 - Sound Waves references water waves 2 - Water is analogy for Sound Waves 3 - Radio

  8. Scanning Probe Alloying Nanolithography (SPAN) 

    E-Print Network [OSTI]

    Lee, Hyungoo

    2010-07-14

    nanowires has been developed. The new technique is called the Scanning Probe Alloying Nanolithography (SPAN). The SPAN was processed using an Atomic Force Microscope (AFM) in ambient environment. Firstly, an AFM probe was coated with gold (Au), and then slid...

  9. A multiplicity result for solitary gravitycapillary waves in deep water via criticalpoint theory

    E-Print Network [OSTI]

    Bath, University of

    A multiplicity result for solitary gravity­capillary waves in deep water via critical­point theory considers the existence of solitary­wave solutions to the classical water­wave problem, which concerns of the water and the velocity of the solitary wave. Intro­ ducing dimensionless variables, one finds

  10. SEPTEMBER 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves

    E-Print Network [OSTI]

    Pierce, Stephen

    SEPTEMBER 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves J. N. MOUM1 , J. M of coastline. The energy transported by these waves includes a nonlinear advection term uE that is negligible in linear internal waves. Unlike linear internal waves, the pressure-velocity energy flux up includes

  11. APRIL 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves

    E-Print Network [OSTI]

    Pierce, Stephen

    APRIL 2006 MOUM ET. AL. 1 Energy Transport by Nonlinear Internal Waves J. N. MOUM1 , J. M. KLYMAK2. The energy transported by these waves includes a nonlinear advection term uE that is negligible in linear internal waves. Unlike linear internal waves, the pressure-velocity energy flux up includes important

  12. Gravitational Waves from Neutron Stars: A Review

    E-Print Network [OSTI]

    Paul D. Lasky

    2015-08-26

    Neutron stars are excellent emitters of gravitational waves. Squeezing matter beyond nuclear densities invites exotic physical processes, many of which violently transfer large amounts of mass at relativistic velocities, disrupting spacetime and generating copious quantities of gravitational radiation. I review mechanisms for generating gravitational waves with neutron stars. This includes gravitational waves from radio and millisecond pulsars, magnetars, accreting systems and newly born neutron stars, with mechanisms including magnetic and thermoelastic deformations, various stellar oscillation modes and core superfluid turbulence. I also focus on what physics can be learnt from a gravitational wave detection, and where additional research is required to fully understand the dominant physical processes at play.

  13. Gravitational Waves from Neutron Stars: A Review

    E-Print Network [OSTI]

    Lasky, Paul D

    2015-01-01

    Neutron stars are excellent emitters of gravitational waves. Squeezing matter beyond nuclear densities invites exotic physical processes, many of which violently transfer large amounts of mass at relativistic velocities, disrupting spacetime and generating copious quantities of gravitational radiation. I review mechanisms for generating gravitational waves with neutron stars. This includes gravitational waves from radio and millisecond pulsars, magnetars, accreting systems and newly born neutron stars, with mechanisms including magnetic and thermoelastic deformations, various stellar oscillation modes and core superfluid turbulence. I also focus on what physics can be learnt from a gravitational wave detection, and where additional research is required to fully understand the dominant physical processes at play.

  14. Paper waves in the wind

    E-Print Network [OSTI]

    Jia, Pan; Claudin, Philippe

    2015-01-01

    A flexible sheet clamped at both ends and submitted to a permanent wind is unstable and propagates waves. Here, we experimentally study the selection of frequency and wavenumber as a function of the wind velocity. These quantities obey simple scaling laws, which are analytically derived from a linear stability analysis of the problem, and which also involve a gravity-induced velocity scale. This approach allows us to collapse data obtained with sheets whose flexible rigidity is varied by two orders of magnitude. This principle may be applied in the future for energy harvesting.

  15. Broadband extended emission in gravitational waves from core-collapse supernovae

    E-Print Network [OSTI]

    Levinson, Amir; Pick, Guy

    2015-01-01

    Black holes in core-collapse of massive stars are expected to surge in mass and angular momentum by hyper-accretion immediately following their formation. We here describe a general framework of extended emission in gravitational waves from non-axisymmetric accretion flows from fallback matter of the progenitor envelope. It shows (a) a maximum efficiency in conversion of accretion energy into gravitational waves at hyper-accretion rates exceeding a critical value set by the ratio of the quadrupole mass inhomogeneity and viscosity with (b) a peak characteristic strain amplitude at the frequency $f_b=\\Omega_b/\\pi$, where $\\Omega_b$ is the Keplerian angular velocity at which viscous torques equal angular momentum loss in gravitational radiation, with $h_{char}\\propto f^{1/6}$ at $ff_b$. Upcoming gravitational wave observations may probe this scaling by extracting broadband spectra using time-sliced matched filtering with chirp templates, recently developed for identifying turbulence in noisy time series.

  16. Deep-water gravity waves: theoretical estimating of wave parameters

    E-Print Network [OSTI]

    Mindlin, Ilia M

    2014-01-01

    This paper addresses deep-water gravity waves of finite amplitude generated by an initial disturbance to the water. It is assumed that the horizontal dimensions of the initially disturbed body of the water are much larger than the magnitude of the free surface displacement in the origin of the waves. Initially the free surface has not yet been displaced from its equilibrium position, but the velocity field has already become different from zero. This means that the water at rest initially is set in motion suddenly by an impulse. Duration of formation of the wave origin and the maximum water elevation in the origin are estimated using the arrival times of the waves and the maximum wave-heights at certain locations obtained from gauge records at the locations, and the distances between the centre of the origin and each of the locations. For points situated at a long distance from the wave origin, forecast is made for the travel time and wave height at the points. The forecast is based on the data recorded by th...

  17. Dark Energy Probes of Dark Energy

    E-Print Network [OSTI]

    Weijgaert, Rien van de

    19/12/2013 1 Dark Energy Probes of Dark Energy Probes Dark Energy Supernovae Ia probing luminosity (Betti numbers) #12;19/12/2013 2 Dark Energy Probes: Comparison Method Strengths Weaknesses Systematics

  18. System and method for determining coolant level and flow velocity in a nuclear reactor

    DOE Patents [OSTI]

    Brisson, Bruce William; Morris, William Guy; Zheng, Danian; Monk, David James; Fang, Biao; Surman, Cheryl Margaret; Anderson, David Deloyd

    2013-09-10

    A boiling water reactor includes a reactor pressure vessel having a feedwater inlet for the introduction of recycled steam condensate and/or makeup coolant into the vessel, and a steam outlet for the discharge of produced steam for appropriate work. A fuel core is located within a lower area of the pressure vessel. The fuel core is surrounded by a core shroud spaced inward from the wall of the pressure vessel to provide an annular downcomer forming a coolant flow path between the vessel wall and the core shroud. A probe system that includes a combination of conductivity/resistivity probes and/or one or more time-domain reflectometer (TDR) probes is at least partially located within the downcomer. The probe system measures the coolant level and flow velocity within the downcomer.

  19. SHIP VELOCITY FIELDS , Lichuan Guib

    E-Print Network [OSTI]

    Gui, Lichuan

    and with free surface, bow flow, wave hydrodynamics, propulsor hydrodynamics, appendages, and cavitation extensive use of PIV for measurement of ship-hydrodynamic flows. In fact, PIV is fast replacing techniques of micro-scale flow structures so that new physics can be studied such as cavitation. Refinement

  20. Vacuum Waves

    E-Print Network [OSTI]

    Paul S. Wesson

    2012-12-11

    As an example of the unification of gravitation and particle physics, an exact solution of the five-dimensional field equations is studied which describes waves in the classical Einstein vacuum. While the solution is essentially 5D in nature, the waves exist in ordinary 3D space, and may provide a way to test for an extra dimension.

  1. PUBLISHED ONLINE: 20 MAY 2012 | DOI: 10.1038/NPHYS2320 Probing an ultracold-atom crystal with

    E-Print Network [OSTI]

    Loss, Daniel

    ,15 , probes of high spectral brightness are readily available by using atoms from a Bose­Einstein condensate atoms can be used for this purpose. Using a one-dimensional Bose gas as a source of matter waves, we. In this work we study the scattering of an atomic probe, consisting of one-dimensional Bose gases, from target

  2. Estimating seismic velocities at ultrasonic frequencies in partially saturated rocks

    SciTech Connect (OSTI)

    Mavko, G.; Nolen-Hoeksema, R. (Stanford Univ., CA (United States). Dept. of Geophysics)

    1994-02-01

    Seismic velocities in rocks at ultrasonic frequencies depend not only on the degree of saturation but also on the distribution of the fluid phase at various scales within the pore space. Two scales of saturation heterogeneity are important: (1) saturation differences between thin compliant pores and larger stiffer pores, and (2) differences between saturated patches and undersaturated patches at a scale much larger than any pore. The authors propose a formalism for predicting the range of velocities in partially saturated rocks that avoids assuming idealized pore shapes by using measured dry rock velocity versus pressure and dry rock porosity versus pressure. The pressure dependence contains all of the necessary information about the distribution of pore compliance for estimating effects of saturation at the finest scales where small amounts of fluid in the thinnest, most compliant parts of the pore space stiffen the rock in both compression and shear (increasing both P- and S-wave velocities) in approximately the same way that confining pressure stiffens the rock by closing the compliant pores. Large-scale saturation patches tend to increase only the high-frequency bulk modulus by amounts roughly proportional to the saturation. The pore-scale effects will be most important at laboratory and logging frequencies when pore-scale pore pressure gradients are unrelaxed. The patchy-saturation effects can persist even at seismic field frequencies if the patch sizes are sufficiently large and the diffusivities are sufficiently low for the larger-scale pressure gradients to be unrelaxed.

  3. Traveling waves in yeast extract and in cultures of Dictyostelium discoideum

    E-Print Network [OSTI]

    Steinbock, Oliver

    ­Zhabo- tinsky (BZ) reaction (cf. Ref. [9]). The velocity v of the excitation waves depends in general reaction step according to the relation v (k D)1/2 . Deviations from the constant velocity of a single traveling reaction-diffusion waves occur in response to oscillatory reactions. Glycolytic degradation

  4. 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.

    1995-07-01

    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.

  5. Measuring In-Situ Mdf Velocity Of Detonation

    DOE Patents [OSTI]

    Horine, Frank M. (Albuquerque, NM); James, Jr., Forrest B. (Albuquerque, NM)

    2005-10-25

    A system for determining the velocity of detonation of a mild detonation fuse mounted on the surface of a device includes placing the device in a predetermined position with respect to an apparatus that carries a couple of sensors that sense the passage of a detonation wave at first and second spaced locations along the fuse. The sensors operate a timer and the time and distance between the locations is used to determine the velocity of detonation. The sensors are preferably electrical contacts that are held spaced from but close to the fuse such that expansion of the fuse caused by detonation causes the fuse to touch the contact, causing an electrical signal to actuate the timer.

  6. 1. INTRODUCTION The investigation of whistler waves excitation and propagation in Earth

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    disturbance near antenna was about Bmax/B0~5%. #12;High frequency probe whistler waves (f0=80-200 MHz) were magnetic field disturbance the whistler wave (frequency f0=160 MHz is close to local electron cyclotron and parametric whistler wave interaction with plasma density and magnetic field variations. Amplitude-frequency

  7. Electromagnetic Probes in PHENIX

    E-Print Network [OSTI]

    Gabor David

    2006-09-21

    Electromagnetic probes are arguably the most universal tools to study the different physics processes in high energy hadron and heavy ion collisions. In this paper we summarize recent measurements of real and virtual direct photons at central rapidity by the PHENIX experiment at RHIC in p+p, d+Au and Au+Au collisions. We also discuss the impact of the results and the constraints they put on theoretical models. At the end we report on the immediate as well as on the mid-term future of photon measurements at RHIC.

  8. Probing metal solidification nondestructively

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) by Carbon-Rich Matrices inPrincipalFirm Exchange . . .Probing metal

  9. The stellar wind velocity field of HD 77581

    E-Print Network [OSTI]

    Manousakis, A

    2015-01-01

    The early acceleration of stellar winds in massive stars is poorly constrained. The scattering of hard X-ray photons emitted by the pulsar in the high-mass X-ray binary Vela X-1 can be used to probe the stellar wind velocity and density profile close to the surface of its supergiant companion HD 77581. We built a high signal-to-noise and high resolution hard X-ray lightcurve of Vela X-1 measured by Swift/BAT over 300 orbital periods of the system and compared it with the predictions of a grid of hydrodynamic simulations. We obtain a very good agreement between observations and simulations for a narrow set of parameters, implying that the wind velocity close to the stellar surface is twice larger than usually assumed with the standard beta law. Locally a velocity gradient of $\\beta\\sim0.5$ is favoured. Even if still incomplete, hydrodynamic simulations are successfully reproducing several observational properties of Vela X-1.

  10. Velocity condensation for magnetotactic bacteria

    E-Print Network [OSTI]

    Rupprecht, Jean-Francois; Bocquet, Lydéric

    2015-01-01

    Magnetotactic swimmers tend to align along magnetic field lines against stochastic reorientations. We show that the swimming strategy, e.g. active Brownian motion versus run-and-tumble dynamics, strongly affects the orientation statistics. The latter can exhibit a velocity condensation whereby the alignment probability density diverges. As a consequence, we find that the swimming strategy affects the nature of the phase transition to collective motion, indicating that L\\'evy run-and-tumble walks can outperform active Brownian processes as strategies to trigger collective behavior.

  11. Newberry EGS Seismic Velocity Model

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Templeton, Dennise

    We use ambient noise correlation (ANC) to create a detailed image of the subsurface seismic velocity at the Newberry EGS site down to 5 km. We collected continuous data for the 22 stations in the Newberry network, together with 12 additional stations from the nearby CC, UO and UW networks. The data were instrument corrected, whitened and converted to single bit traces before cross correlation according to the methodology in Benson (2007). There are 231 unique paths connecting the 22 stations of the Newberry network. The additional networks extended that to 402 unique paths crossing beneath the Newberry site.

  12. Newberry EGS Seismic Velocity Model

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    Templeton, Dennise

    2013-10-01

    We use ambient noise correlation (ANC) to create a detailed image of the subsurface seismic velocity at the Newberry EGS site down to 5 km. We collected continuous data for the 22 stations in the Newberry network, together with 12 additional stations from the nearby CC, UO and UW networks. The data were instrument corrected, whitened and converted to single bit traces before cross correlation according to the methodology in Benson (2007). There are 231 unique paths connecting the 22 stations of the Newberry network. The additional networks extended that to 402 unique paths crossing beneath the Newberry site.

  13. Laboratory Study Investigating the Three-dimensional Turbulence and Kinematic Properties Associated with a Breaking Solitary Wave 

    E-Print Network [OSTI]

    Swigler, David Townley

    2010-10-12

    was used to generate the wave, while the free surface elevations and fluid velocities were measured using wave gauges and three-dimensional acoustic-Doppler velocimeters (ADVs), respectively. From the free surface elevations, the evolution and runup...

  14. Method of accelerating photons by a relativistic plasma wave

    DOE Patents [OSTI]

    Dawson, John M. (Pacific Palisades, CA); Wilks, Scott C. (Santa Monica, CA)

    1990-01-01

    Photons of a laser pulse have their group velocity accelerated in a plasma as they are placed on a downward density gradient of a plasma wave of which the phase velocity nearly matches the group velocity of the photons. This acceleration results in a frequency upshift. If the unperturbed plasma has a slight density gradient in the direction of propagation, the photon frequencies can be continuously upshifted to significantly greater values.

  15. Resonance Van Hove Singularities in Wave Kinetics

    E-Print Network [OSTI]

    Yi-Kang Shi; Gregory Eyink

    2015-07-29

    Wave kinetic theory has been developed to describe the statistical dynamics of weakly nonlinear, dispersive waves. However, we show that systems which are generally dispersive can have resonant sets of wave modes with identical group velocities, leading to a local breakdown of dispersivity. This shows up as a geometric singularity of the resonant manifold and possibly as an infinite phase measure in the collision integral. Such singularities occur widely for classical wave systems, including acoustical waves, Rossby waves, helical waves in rotating fluids, light waves in nonlinear optics and also in quantum transport, e.g. kinetics of electron-hole excitations (matter waves) in graphene. These singularities are the exact analogue of the critical points found by Van Hove in 1953 for phonon dispersion relations in crystals. The importance of these singularities in wave kinetics depends on the dimension of phase space $D=(N-2)d$ ($d$ physical space dimension, $N$ the number of waves in resonance) and the degree of degeneracy $\\delta$ of the critical points. Following Van Hove, we show that non-degenerate singularities lead to finite phase measures for $D>2$ but produce divergences when $D\\leq 2$ and possible breakdown of wave kinetics if the collision integral itself becomes too large (or even infinite). Similar divergences and possible breakdown can occur for degenerate singularities, when $D-\\delta\\leq 2,$ as we find for several physical examples, including electron-hole kinetics in graphene. When the standard kinetic equation breaks down, then one must develop a new singular wave kinetics. We discuss approaches from pioneering 1971 work of Newell \\& Aucoin on multi-scale perturbation theory for acoustic waves and field-theoretic methods based on exact Schwinger-Dyson integral equations for the wave dynamics.

  16. Probing Multiparton Correlations at CEBAF

    E-Print Network [OSTI]

    Jianwei Qiu

    1998-08-08

    In this talk, I explore the possibilities of probing the multiparton correlation functions at CEBAF at its current energy and the energies with its future upgrades.

  17. Variable path length spectrophotometric probe

    DOE Patents [OSTI]

    O'Rourke, Patrick E. (157 Greenwood Dr., Martiney, GA 30907); McCarty, Jerry E. (104 Recreation Dr., Aiken, SC 29803); Haggard, Ricky A. (1144 Thornwood Drive, North Augusta, SC 29891)

    1992-01-01

    A compact, variable pathlength, fiber optic probe for spectrophotometric measurements of fluids in situ. The probe comprises a probe body with a shaft having a polished end penetrating one side of the probe, a pair of optic fibers, parallel and coterminous, entering the probe opposite the reflecting shaft, and a collimating lens to direct light from one of the fibers to the reflecting surface of the shaft and to direct the reflected light to the second optic fiber. The probe body has an inlet and an outlet port to allow the liquid to enter the probe body and pass between the lens and the reflecting surface of the shaft. A linear stepper motor is connected to the shaft to cause the shaft to advance toward or away from the lens in increments so that absorption measurements can be made at each of the incremental steps. The shaft is sealed to the probe body by a bellows seal to allow freedom of movement of the shaft and yet avoid leakage from the interior of the probe.

  18. Investigation of Wave Energy Converter Effects on Near-shore Wave Fields: Model Generation Validation and Evaluation - Kaneohe Bay HI.

    SciTech Connect (OSTI)

    Roberts, Jesse D.; Chang, Grace; Jones, Craig

    2014-09-01

    The numerical model, SWAN (Simulating WAves Nearshore) , was used to simulate wave conditions in Kaneohe Bay, HI in order to determine the effects of wave energy converter ( WEC ) devices on the propagation of waves into shore. A nested SWAN model was validated then used to evaluate a range of initial wave conditions: significant wave heights (H s ) , peak periods (T p ) , and mean wave directions ( MWD) . Differences between wave height s in the presence and absence of WEC device s were assessed at locations in shore of the WEC array. The maximum decrease in wave height due to the WEC s was predicted to be approximately 6% at 5 m and 10 m water depths. Th is occurred for model initiation parameters of H s = 3 m (for 5 m water depth) or 4 m (10 m water depth) , T p = 10 s, and MWD = 330deg . Subsequently, bottom orbital velocities were found to decrease by about 6%.

  19. Over the past 10 years, there has been a consistent increase in using 3D P-wave data to characterize fractures, which is

    E-Print Network [OSTI]

    Edinburgh, University of

    of otherwise low permeability. Here, we pre- sent a case study of fracture detection using 3D P-wave seismic the narrow-azimuth stack- ing method is applicable to the velocity and AVO gradient attributes. Study area-wave seismic attributes, such as traveltime, stacking velocity, reflected wave amplitudes, impedance, etc. can

  20. Self-consistent theory of capillary-gravity-wave generation by small moving objects A. D. Chepelianskii,1

    E-Print Network [OSTI]

    Raphael, Elie

    Self-consistent theory of capillary-gravity-wave generation by small moving objects A. D for example, wig- gling beetles may take advantage of the generation of capillary-gravity waves for echo/s. An object moving at constant velocity V cmin does not generate steady waves and the wave resis- tance

  1. Slow Waves in Fractures Filled with Viscous Fluid

    SciTech Connect (OSTI)

    Korneev, Valeri

    2008-01-08

    Stoneley guided waves in a fluid-filled fracture generally have larger amplitudes than other waves, and therefore, their properties need to be incorporated in more realistic models. In this study, a fracture is modeled as an infinite layer of viscous fluid bounded by two elastic half-spaces with identical parameters. For small fracture thickness, I obtain a simple dispersion equation for wave-propagation velocity. This velocity is much smaller than the velocity of a fluid wave in a Biot-type solution, in which fracture walls are assumed to be rigid. At seismic prospecting frequencies and realistic fracture thicknesses, the Stoneley guided wave has wavelengths on the order of several meters and an attenuation Q factor exceeding 10, which indicates the possibility of resonance excitation in fluid-bearing rocks. The velocity and attenuation of Stoneley guided waves are distinctly different at low frequencies for water and oil. The predominant role of fractures in fluid flow at field scales is supported by permeability data showing an increase of several orders of magnitude when compared to values obtained at laboratory scales. These data suggest that Stoneley guided waves should be taken into account in theories describing seismic wave propagation in fluid-saturated rocks.

  2. Velocity structure of the uppermost mantle beneath East Asia from Pn tomography and its dynamic implications

    E-Print Network [OSTI]

    Niu, Fenglin

    regions on Earth's surface due to the collision from the India plate and the suctions induced seismicity of the area, we conducted a Pn traveltime tomography to estimate the compressive wave speed. In each region, stable blocks tend to have high Pn velocity while the boundary regions, which show a high

  3. Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Satish Pullammanappallil

    E-Print Network [OSTI]

    Louis, Sushil J.

    Seismic Velocity Inversion with Genetic Algorithms Sushil J. Louis Qinxue Chen Satish to compute travel times for seismic waves. However, in practice, we have to solve the inverse problem: travel synthetic seismic models shows that large population sizes are crit- ical to generating good seismic

  4. Low Frequency Scattering Resonance Wave in Strong Heterogeneity

    E-Print Network [OSTI]

    Liu, Yinbin

    2015-01-01

    Multiple scattering of wave in strong heterogeneity can cause resonance-like wave phenomenon where signal exhibits low frequency, high intensity, and slowly propagating velocity. For example, long period event in volcanic seismology and surface plasmon wave and quantum Hall effect in wave-particle interactions. Collective behaviour in a many-body system is usually thought to be the source for generating the anomaly. However, the detail physical mechanism is not fully understood. Here I show by wave field modeling for microscopic bubble cloud model and 1D heterogeneity that the anomaly is related to low frequency scattering resonance happened in transient regime. This low frequency resonance is a kind of wave coherent scattering enhancement phenomenon in strongly-scattered small-scale heterogeneity. Its resonance frequency is inversely proportional to heterogeneous scale and contrast and will further shift toward lower frequency with random heterogeneous scale and velocity fluctuations. Low frequency scatterin...

  5. Supernovae as cosmological probes

    E-Print Network [OSTI]

    Nielsen, Jeppe Trost

    2015-01-01

    The cosmological standard model at present is widely accepted as containing mainly things we do not understand. In particular the appearance of a Cosmological Constant, or dark energy, is puzzling. This was first inferred from the Hubble diagram of a low number of Type Ia supernovae, and later corroborated by complementary cosmological probes. Today, a much larger collection of supernovae is available, and here I perform a rigorous statistical analysis of this dataset. Taking into account how the supernovae are calibrated to be standard candles, we run into some subtleties in the analysis. To our surprise, this new dataset - about an order of bigger than the size of the original dataset - shows, under standard assumptions, only mild evidence of an accelerated universe.

  6. Heat transfer probe

    DOE Patents [OSTI]

    Frank, Jeffrey I.; Rosengart, Axel J.; Kasza, Ken; Yu, Wenhua; Chien, Tai-Hsin; Franklin, Jeff

    2006-10-10

    Apparatuses, systems, methods, and computer code for, among other things, monitoring the health of samples such as the brain while providing local cooling or heating. A representative device is a heat transfer probe, which includes an inner channel, a tip, a concentric outer channel, a first temperature sensor, and a second temperature sensor. The inner channel is configured to transport working fluid from an inner inlet to an inner outlet. The tip is configured to receive at least a portion of the working fluid from the inner outlet. The concentric outer channel is configured to transport the working fluid from the inner outlet to an outer outlet. The first temperature sensor is coupled to the tip, and the second temperature sensor spaced apart from the first temperature sensor.

  7. Detonation waves in pentaerythritol tetranitrate

    SciTech Connect (OSTI)

    Tarver, C.M.; Breithaupt, R.D.; Kury, J.W.

    1997-06-01

    Fabry{endash}Perot laser interferometry was used to obtain nanosecond time resolved particle velocity histories of the free surfaces of tantalum discs accelerated by detonating pentaerythritol tetranitrate (PETN) charges and of the interfaces between PETN detonation products and lithium fluoride crystals. The experimental records were compared to particle velocity histories calculated using very finely zoned meshes of the exact dimensions with the DYNA2D hydrodynamic code. The duration of the PETN detonation reaction zone was demonstrated to be less than the 5 ns initial resolution of the Fabry{endash}Perot technique, because the experimental records were accurately calculated using an instantaneous chemical reaction, the Chapman{endash}Jouguet (C-J) model of detonation, and the reaction product Jones{endash}Wilkins{endash}Lee (JWL) equation of state for PETN detonation products previously determined by supracompression (overdriven detonation) studies. Some of the PETN charges were pressed to densities approaching the crystal density and exhibited the phenomenon of superdetonation. An ignition and growth Zeldovich{endash}von Neumann{endash}Doring (ZND) reactive flow model was developed to explain these experimental records and the results of previous PETN shock initiation experiments on single crystals of PETN. Good agreement was obtained for the induction time delays preceding chemical reaction, the run distances at which the initial shock waves were overtaken by the detonation waves in the compressed PETN, and the measured particle velocity histories produced by the overdriven detonation waves before they could relax to steady state C-J velocity and pressure. {copyright} {ital 1997 American Institute of Physics.}

  8. Nonlinear acoustic wave generation in a three-phase seabed

    E-Print Network [OSTI]

    Kukarkin, A B; Zhileikin, Ya M

    2015-01-01

    Generation of an acoustic wave by two pump sound waves is studied in a three-phase marine sediment that consists of a solid frame and the pore water with air bubbles in it. To avoid shock-wave formation the interaction is considered in the frequency range where there is a significant amount of sound velocity dispersion. Nonlinear equations are obtained to describe the interaction of acoustic waves in the presence of air bubbles. An expression for the amplitude of the generated wave is obtained and numerical analysis of its dependence on distance and on the resonance frequency of bubbles is performed.

  9. Nonlinear acoustic wave generation in a three-phase seabed

    E-Print Network [OSTI]

    A. B. Kukarkin; N. I. Pushkina; Ya. M. Zhileikin

    2015-03-03

    Generation of an acoustic wave by two pump sound waves is studied in a three-phase marine sediment that consists of a solid frame and the pore water with air bubbles in it. To avoid shock-wave formation the interaction is considered in the frequency range where there is a significant amount of sound velocity dispersion. Nonlinear equations are obtained to describe the interaction of acoustic waves in the presence of air bubbles. An expression for the amplitude of the generated wave is obtained and numerical analysis of its dependence on distance and on the resonance frequency of bubbles is performed.

  10. Wave Propagation in Multiferroic Materials

    E-Print Network [OSTI]

    Keller, Scott Macklin

    2013-01-01

    130 SAW Waves . . . . . . . . . . . . . .QuasiStatic MEE Waves . . . . . . . . . . . . . . . . . . .General MEE Wave Solution . . . . . . . . . . . .

  11. Rotating concave eddy current probe

    DOE Patents [OSTI]

    Roach, Dennis P. (Albuquerque, NM); Walkington, Phil (Albuquerque, NM); Rackow, Kirk A. (Albuquerque, NM); Hohman, Ed (Albuquerque, NM)

    2008-04-01

    A rotating concave eddy current probe for detecting fatigue cracks hidden from view underneath the head of a raised head fastener, such as a buttonhead-type rivet, used to join together structural skins, such as aluminum aircraft skins. The probe has a recessed concave dimple in its bottom surface that closely conforms to the shape of the raised head. The concave dimple holds the probe in good alignment on top of the rivet while the probe is rotated around the rivet's centerline. One or more magnetic coils are rigidly embedded within the probe's cylindrical body, which is made of a non-conducting material. This design overcomes the inspection impediment associated with widely varying conductivity in fastened joints.

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

    E-Print Network [OSTI]

    Sutherland, Bruce

    Internal wave instability: Wave-wave versus wave-induced mean flow interactions B. R. Sutherland fluid, vertically propagating internal gravity waves of moderately large amplitude can become unstable, energy from primary waves is transferred, for example, to waves with half frequency. Self

  13. Cavitation controlled acoustic probe for fabric spot cleaning and moisture monitoring

    DOE Patents [OSTI]

    Sheen, Shuh-Haw (Naperville, IL); Chien, Hual-Te (Naperville, IL); Raptis, Apostolos C. (Downers Grove, IL)

    1997-01-01

    A method and apparatus are provided for monitoring a fabric. An acoustic probe generates acoustic waves relative to the fabric. An acoustic sensor, such as an accelerometer is coupled to the acoustic probe for generating a signal representative of cavitation activity in the fabric. The generated cavitation activity representative signal is processed to indicate moisture content of the fabric. A feature of the invention is a feedback control signal is generated responsive to the generated cavitation activity representative signal. The feedback control signal can be used to control the energy level of the generated acoustic waves and to control the application of a cleaning solution to the fabric.

  14. Dissipative electromagnetic solitary waves in collisional plasmas

    SciTech Connect (OSTI)

    Borhanian, Jafar [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P.O.Box 179, Ardabil (Iran, Islamic Republic of)

    2012-08-15

    The propagation of linearly polarized electromagnetic (EM) waves in a collisional plasma is studied using multiple scale perturbation technique in a weakly nonlinear regime. A complex linear dispersion relation and a complex group velocity are obtained for EM waves propagating in a plasma and their dependence on system parameters is investigated. It is shown that the amplitude of EM pulse is governed by an envelope equation similar to a cubic complex Ginzburg-Landau equation. A traveling bright solitary wave solution for envelope equation is found, its existence condition in parameter space is explored and variation of its profile with system parameters is manipulated. Monitoring temporal evolution of traveling solitary wave solution provides more insight into the nature of this solution and ensures that depending on the parameters of the system, solitary wave solution may behave like a stationary soliton or may exhibit the behavior of a breathing soliton.

  15. Controlling Velocity In Bipedal Walking: A Dynamic Programming Approach

    E-Print Network [OSTI]

    Atkeson, Christopher G.

    velocity and swing leg angle and angular velocity) to 1 (stance leg angular velocity). RepercussionsControlling Velocity In Bipedal Walking: A Dynamic Programming Approach Thijs Mandersloot their velocity. We control velocity by using dynamic programming to design control laws for each desired velocity

  16. Probing the kinesin reaction cycle with a 2D optical force clamp

    E-Print Network [OSTI]

    Asbury, Chip

    Probing the kinesin reaction cycle with a 2D optical force clamp Steven M. Block* , Charles L) With every step it takes, the kinesin motor undergoes a mechano- chemical reaction cycle that includes velocity depends on both the magnitude and the direction of the applied load. Using specialized apparatus

  17. A strategy for oligonucleotide microarray probe reduction

    E-Print Network [OSTI]

    Antipova, Alena A.

    Background: One of the factors limiting the number of genes that can be analyzed on high-density oligonucleotide arrays is that each transcript is probed by multiple oligonucleotide probes. To reduce the number of probes ...

  18. Shallow Water Waves and Solitary Waves

    E-Print Network [OSTI]

    Hereman, Willy

    2013-01-01

    Encyclopedic article covering shallow water wave models used in oceanography and atmospheric science. Sections: Definition of the Subject; Introduction and Historical Perspective; Completely Integrable Shallow Water Wave Equations; Shallow Water Wave Equations of Geophysical Fluid Dynamics; Computation of Solitary Wave Solutions; Numerical Methods; Water Wave Experiments and Observations; Future Directions, and Bibliography.

  19. Origin of coda waves: earthquake source resonance

    E-Print Network [OSTI]

    Liu, Yinbin

    2015-01-01

    Seismic coda in local earthquake exhibits the characteristics of uniform spatial distribution energy, selective frequency, and slow temporal decay oscillation. It is usually assumed to be the incoherent waves scattered from random heterogeneity in the earth's lithosphere. Here I show by wave field modeling for 1D heterogeneity that seismic coda is related to the natural resonance of earthquake source around the earthquake's focus. This natural resonance is a kind of wave coherent scattering enhancement phenomenon or coupling oscillations happened in steady state regime in strong small-scale heterogeneity. Its resonance frequency is inversely proportional to the heterogeneous scale and contrast and will shift toward lower frequency with increasing random heterogeneous scale and velocity fluctuations. Its energy weakens with decreasing impedance contrast and increasing random heterogeneous scale and velocity fluctuations.

  20. December 23, 2004 High Cadence Radio Observations of an EIT Wave

    E-Print Network [OSTI]

    White, Stephen

    December 23, 2004 High Cadence Radio Observations of an EIT Wave S. M. White1 and B. J. Thompson2 ABSTRACT Sensitive radio observations of the 1997 September 24 EIT wave show its velocity to be 830 km s-1 result is that no deceleration is observed during the 4 minutes that the wave is visible in the radio

  1. Numerical studies of current generation by radio-frequency traveling waves

    E-Print Network [OSTI]

    Karney, Charles

    Numerical studies of current generation by radio-frequency traveling waves Charles F. F. Karney January 1979; final manuscript received 7 May 1979) By injecting radio-frequency traveling waves of the fusion power output. Recently,' the damping of high-phase-velocity radio- frequency traveling waves has

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

    E-Print Network [OSTI]

    Aste, Andreas

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

  3. Linear wave dispersion laws in unmagnetized relativistic plasma: Analytical and numerical results

    E-Print Network [OSTI]

    Linear wave dispersion laws in unmagnetized relativistic plasma: Analytical and numerical results laws for electrostatic and electromagnetic waves in a homogeneous and unmagnetized relativistic Vlasov plasma frequency pe , Debye wave number kD and the thermal velocity vth,e is established. The approximate

  4. Fiberoptic probe and system for spectral measurements

    DOE Patents [OSTI]

    Dai, S.; Young, J.P.

    1998-10-13

    A fused fiberoptic probe, a system, method and embodiments thereof for conducting spectral measurements are disclosed. The fused fiberoptic probe comprises a probe tip having a specific geometrical configuration, an exciting optical fiber and at least one collection optical fiber fused within a housing, preferably silica. The specific geometrical configurations in which the probe tip can be shaped include a slanted probe tip with an angle greater than 0{degree}, an inverted cone-shaped probe tip, and a lens head. 12 figs.

  5. Long duration ash probe

    DOE Patents [OSTI]

    Hurley, John P. (Grand Forks, ND); McCollor, Don P. (Grand Forks, ND); Selle, Stanley J. (Grand Forks, MN)

    1994-01-01

    A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during sootblowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon.

  6. Long duration ash probe

    DOE Patents [OSTI]

    Hurley, J.P.; McCollor, D.P.; Selle, S.J.

    1994-07-26

    A long duration ash probe includes a pressure shell connected to a port in a combustor with a sample coupon mounted on a retractable carriage so as to retract the sample coupon within the pressure shell during soot blowing operation of the combustor. A valve mounted at the forward end of the pressure shell is selectively closeable to seal the sample coupon within the shell, and a heating element in the shell is operable to maintain the desired temperature of the sample coupon while retracted within the shell. The carriage is operably mounted on a pair of rails within the shell for longitudinal movement within the shell. A hollow carrier tube connects the hollow cylindrical sample coupon to the carriage, and extends through the carriage and out the rearward end thereof. Air lines are connected to the rearward end of the carrier tube and are operable to permit coolant to pass through the air lines and thence through the carrier tube to the sample coupon so as to cool the sample coupon. 8 figs.

  7. Single point aerosol sampling: Evaluation of mixing and probe performance in a nuclear stack

    SciTech Connect (OSTI)

    Rodgers, J.C.; Fairchild, C.I.; Wood, G.O.; Ortiz, C.A.; Muyshondt, A.; McFarland, A.R. |

    1994-12-31

    Alternative Reference Methodologies (ARMS) have been developed for sampling of radionuclide; from stacks and ducts that differ from the methods required by the US EPA. The EPA methods are prescriptive in selection of sampling locations and in design of sampling probes whereas the alternative methods are performance driven. Tests were conducted in a stack at Los Alamos National Laboratory to demonstrate the efficacy of the ARMS. Coefficients of variation of the velocity tracer gas, and aerosol particle profiles were determined at three sampling locations. Results showed numerical criteria placed upon the coefficients of variation by the ARMs were met at sampling stations located 9 and 14 stack diameters from flow entrance, but not at a location that is 1.5 diameters downstream from the inlet. Experiments were conducted to characterize the transmission of 10 {mu}m aerodynamic equivalent diameter liquid aerosol particles through three types of sampling probes. The transmission ratio (ratio of aerosol concentration at the probe exit plane to the concentration in the free stream) was 107% for a 113 L/min (4-cfm) an isokinetic shrouded probe, but only 20% for an isokinetic probe that follows the EPA requirements. A specially designed isokinetic probe showed a transmission ratio of 63%. The shrouded probe performance would conform to the ARM criteria; however, the isokinetic probes would not.

  8. Optic probe for semiconductor characterization

    DOE Patents [OSTI]

    Sopori, Bhushan L. (Denver, CO); Hambarian, Artak (Yerevan, AM)

    2008-09-02

    Described herein is an optical probe (120) for use in characterizing surface defects in wafers, such as semiconductor wafers. The optical probe (120) detects laser light reflected from the surface (124) of the wafer (106) within various ranges of angles. Characteristics of defects in the surface (124) of the wafer (106) are determined based on the amount of reflected laser light detected in each of the ranges of angles. Additionally, a wafer characterization system (100) is described that includes the described optical probe (120).

  9. Numerical simulation of inviscid wave-current interaction with an FPSO 

    E-Print Network [OSTI]

    Bae, Sang-Yun

    2009-05-15

    This study investigated Floating Production Storage and Offloading (FPSO) responses under wave and current interactions. A higher order boundary element method (HOBEM) was adopted to probe the behavior of an FPSO. Forces and moment of an FPSO were...

  10. 3-D seismic velocity and attenuation structures in the geothermal field

    SciTech Connect (OSTI)

    Nugraha, Andri Dian [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Global Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia); Syahputra, Ahmad [Geophyisical Engineering, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Geophyisical Engineering, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia); Fatkhan,; Sule, Rachmat [Applied Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)] [Applied Geophysics Research Group, Faculty of Mining and Petroleum Engineering, Institute of Technology Bandung, Jalan Ganesha No. 10 Bandung, 40132 (Indonesia)

    2013-09-09

    We conducted delay time tomography to determine 3-D seismic velocity structures (Vp, Vs, and Vp/Vs ratio) using micro-seismic events in the geothermal field. The P-and S-wave arrival times of these micro-seismic events have been used as input for the tomographic inversion. Our preliminary seismic velocity results show that the subsurface condition of geothermal field can be fairly delineated the characteristic of reservoir. We then extended our understanding of the subsurface physical properties through determining of attenuation structures (Qp, Qs, and Qs/Qp ratio) using micro-seismic waveform. We combined seismic velocities and attenuation structures to get much better interpretation of the reservoir characteristic. Our preliminary attanuation structures results show reservoir characterization can be more clearly by using the 3-D attenuation model of Qp, Qs, and Qs/Qp ratio combined with 3-D seismic velocity model of Vp, Vs, and Vp/Vs ratio.

  11. arXiv:hep-ph/0502097v110Feb2005 Probing the absolute density of the Earth's core using a neutrino beam

    E-Print Network [OSTI]

    Mcdonough, William F.

    and the positions of these boundaries. Seismic waves geophysics leads to a propagation velocity profile of the Earth of the Earth's core with a vertical neutrino factory baseline at the per cent level for sin2 213 0.01, where we of the Earth's interior has been seismic wave geophysics primarily using seismic waves from earthquakes to re

  12. Moreton Waves and EIT Waves Related to the Flare Events of June 3, 2012 and July 6, 2012

    E-Print Network [OSTI]

    Admiranto, A G; Yus'an, U; Puspitaningrum, E

    2015-01-01

    We present geometrical and kinematical analysis of Moreton waves and EIT waves observed on June 3, 2012 and Moreton waves observed on July 6, 2012. The Moreton waves were recorded in H$\\alpha$ images of Global Oscillation Network Group (GONG) archive and EIT waves obtained from SDO/AIA observations, especially in 193 nm channel. The observed wave of June 3 has angular span of about $70^{\\circ}$ with a broad wave front associated to NOAA active region 11496. It was found that the speed of the wave that started propagating at 17.53 UT is between 950 to 1500 km/s. Related to this wave occurrence, there was solar type II and III radio bursts. The speed of the EIT in this respect about 247 km/sec. On the other hand, the wave of July 6 may be associated to X1.1 class flare that occurred at 23.01 UT around the 11514 active region. From the kinematical analysis, the wave propagated with the initial velocity of about 1180 km/s which is in agreement with coronal shock velocity derived from type II radio burst observati...

  13. Assessment of the 296-S-21 Stack Sampling Probe Location

    SciTech Connect (OSTI)

    Glissmeyer, John A.

    2006-09-08

    Tests were performed to assess the suitability of the location of the air sampling probe on the 296-S-21 stack according to the criteria of ANSI N13.1-1999, Sampling and Monitoring Releases of Airborne Radioactive Substances from the Stacks and Ducts of Nuclear Facilities. Pacific Northwest National Laboratory conducted most tests on a 3.67:1 scale model of the stack. CH2MHill also performed some limited confirmatory tests on the actual stack. The tests assessed the capability of the air-monitoring probe to extract a sample representative of the effluent stream. The tests were conducted for the practical combinations of operating fans and addressed: (1) Angular Flow--The purpose is to determine whether the velocity vector is aligned with the sampling nozzle. The average yaw angle relative to the nozzle axis should not be more than 20. The measured values ranged from 5 to 11 degrees on the scale model and 10 to 12 degrees on the actual stack. (2) Uniform Air Velocity--The gas momentum across the stack cross section where the sample is extracted should be well mixed or uniform. The uniformity is expressed as the variability of the measurements about the mean, the coefficient of variance (COV). The lower the COV value, the more uniform the velocity. The acceptance criterion is that the COV of the air velocity must be ?20% across the center two-thirds of the area of the stack. At the location simulating the sampling probe, the measured values ranged form 4 to 11%, which are within the criterion. To confirm the validity of the scale model results, air velocity uniformity measurements were made both on the actual stack and on the scale model at the test ports 1.5 stack diameters upstream of the sampling probe. The results ranged from 6 to 8% COV on the actual stack and 10 to 13% COV on the scale model. The average difference for the eight runs was 4.8% COV, which is within the validation criterion. The fact that the scale model results were slightly higher than the actual stack suggests that the other test results on the scale model are conservative relative to the actual stack. (3) Uniform Concentration of Tracer Gases--A uniform contaminant concentration in the sampling plane enables the extraction of samples that represent the true concentration. This was first tested using a tracer gas to represent gaseous effluents. The fan is a good mixer, so injecting the tracer downstream of the fans provides worst-case results. The acceptance criteria are that (1) the COV of the measured tracer gas concentration is ?20% across the center two-thirds of the sampling plane and (2) at no point in the sampling plane does the concentration vary from the mean by >30%. The results on the scale model at the point simulating the sampling probe ranged from 0.3 to 6 %COV, and the maximum single point deviation from the mean was -10%. (4) Uniform Concentration of Tracer Particles--Uniformity in contaminant concentration at the sampling probe was further demonstrated using tracer particles large enough to exhibit inertial effects. Particles of 10-?m aerodynamic diameter were used. The acceptance criterion is that the COV of particle concentration is ?20% across the center two-thirds of the sampling plane. The scale model results ranged form 2 to 9%. Based on these tests, the location of the air sampling probe on the 296-S-21 stack meets the requirements of the ANSI/HPS N13.1-1999 standard.

  14. Gravitational Waves in G4v

    E-Print Network [OSTI]

    Mead, Carver

    2015-01-01

    Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown t...

  15. Wave variability and wave spectra for wind generated gravity waves 

    E-Print Network [OSTI]

    Bretschneider, Charles L.

    1959-01-01

    A series of experiments of forces on a fixed vertical truncated column due to Stokes 5th order like waves were done in a wave tank. An effort was made to generate the waves as close as possible to theoretical Stokes 5th order waves. A systematic...

  16. On physical interpretation of two dimensional time-correlations regarding time delay velocities and eddy shaping

    SciTech Connect (OSTI)

    Fedorczak, N. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); CEA, IRFM, F-13108 Saint-Paul-Lez-Durance (France); Manz, P. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); Max-Planck-Institut feur Plasmaphysik, Association Euratom-IPP, 85748Garching (Germany); Thakur, S. C.; Xu, M.; Tynan, G. R. [Center for Momentum Transport and Flow Organization, University of California at San Diego, San Diego, California 92093 (United States); Xu, G. S.; Liu, S. C. [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei 230031 (China)

    2012-12-15

    Time delay estimation (TDE) techniques are frequently used to estimate the flow velocity from fluctuating measurements. Tilted structures carried by the flow lead to misinterpretation of the time delays in terms of velocity direction and amplitude. It affects TDE measurements from probes, and is also intrinsically important for beam emission spectroscopy and gas puff imaging measurements. Local eddy shapes estimated from 2D fluctuating field are necessary to gain a more accurate flow estimate from TDE, as illustrated by Langmuir probe array measurements. A least square regression approach is proposed to estimate both flow field and shaping parameters. The technique is applied to a test case built from numerical simulation of interchange fluctuations. The local eddy shape does not only provide corrections for the velocity field but also quantitative information about the statistical interaction mechanisms between local eddies and E Multiplication-Sign B flow shear. The technique is then tested on gaz puff imaging data collected at the edge of EAST tokamak plasmas. It is shown that poloidal asymmetries of the fluctuation fields-velocity and eddy shape-are consistent at least qualitatively with a ballooning type of turbulence immersed in a radially sheared equilibrium flow.

  17. Discretising the velocity distribution for directional dark matter experiments

    E-Print Network [OSTI]

    Bradley J. Kavanagh

    2015-06-16

    Dark matter (DM) direct detection experiments which are directionally-sensitive may be the only method of probing the full velocity distribution function (VDF) of the Galactic DM halo. We present an angular basis for the DM VDF which can be used to parametrise the distribution in order to mitigate astrophysical uncertainties in future directional experiments and extract information about the DM halo. This basis consists of discretising the VDF in a series of angular bins, with the VDF being only a function of the DM speed $v$ within each bin. In contrast to other methods, such as spherical harmonic expansions, the use of this basis allows us to guarantee that the resulting VDF is everywhere positive and therefore physical. We present a recipe for calculating the event rates corresponding to the discrete VDF for an arbitrary number of angular bins $N$ and investigate the discretisation error which is introduced in this way. For smooth, Standard Halo Model-like distribution functions, only $N=3$ angular bins are required to achieve an accuracy of around $10-30\\%$ in the number of events in each bin. Shortly after confirmation of the DM origin of the signal with around 50 events, this accuracy should be sufficient to allow the discretised velocity distribution to be employed reliably. For more extreme VDFs (such as streams), the discretisation error is typically much larger, but can be improved with increasing $N$. This method paves the way towards an astrophysics-independent analysis framework for the directional detection of dark matter.

  18. Switchable stiffness scanning microscope probe

    E-Print Network [OSTI]

    Mueller-Falcke, Clemens T. (Clemens Tobias)

    2005-01-01

    Atomic Force Microscopy (AFM) has rapidly gained widespread utilization as an imaging device and micro/nano-manipulator during recent years. This thesis investigates the new concept of a dual stiffness scanning probe with ...

  19. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, Brian B. (Aiken, SC); Ballard, Sanford (Albuquerque, NM)

    1994-01-01

    A monitoring probe for detecting groundwater migration. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow.

  20. Monitoring probe for groundwater flow

    DOE Patents [OSTI]

    Looney, B.B.; Ballard, S.

    1994-08-23

    A monitoring probe for detecting groundwater migration is disclosed. The monitor features a cylinder made of a permeable membrane carrying an array of electrical conductivity sensors on its outer surface. The cylinder is filled with a fluid that has a conductivity different than the groundwater. The probe is placed in the ground at an area of interest to be monitored. The fluid, typically saltwater, diffuses through the permeable membrane into the groundwater. The flow of groundwater passing around the permeable membrane walls of the cylinder carries the conductive fluid in the same general direction and distorts the conductivity field measured by the sensors. The degree of distortion from top to bottom and around the probe is precisely related to the vertical and horizontal flow rates, respectively. The electrical conductivities measured by the sensors about the outer surface of the probe are analyzed to determine the rate and direction of the groundwater flow. 4 figs.

  1. GEOPHYSICS, VOL. 66, NO. 3 (MAY-JUNE 2001); P. 897903, 4 FIGS., 1 TABLE. Depth-domain velocity analysis in VTI media using surface

    E-Print Network [OSTI]

    Tsvankin, Ilya

    velocity models needed for depth migration. Here, we demonstrate that P-wave reflection data can for depth imaging (such as prestack depth migration) arises mostly in laterally heteroge- neous media. StillGEOPHYSICS, VOL. 66, NO. 3 (MAY-JUNE 2001); P. 897­903, 4 FIGS., 1 TABLE. Depth-domain velocity

  2. Design and analysis of mismatch probes for long oligonucleotide...

    Office of Scientific and Technical Information (OSTI)

    TECHNOLOGY; MICROORGANISMS; NUCLEOTIDES; OLIGONUCLEOTIDES; PROBES; SIMULATION; TARGETS; THERMODYNAMICS Nonspecific hybridization, hybridizations, oligonucleotide probes, microarray...

  3. Analysis of Ultrasonic Velocities in Hydrocarbon Mixtures

    E-Print Network [OSTI]

    of measurements on ultrasonic velocities of liquid hydrocarbons and mixtures. They found that their dataAnalysis of Ultrasonic Velocities in Hydrocarbon Mixtures James G. Berryman Lawrence Livermore on hydrocarbon mixtures was shown by Wang and Nur [JASA 89, 2725 (1991)] to agree quite well with the predictions

  4. Effect of gas velocity on the weakly nonlinear instability of a planar viscous sheet

    SciTech Connect (OSTI)

    Yang, Li-Jun, E-mail: yanglijun@buaa.edu.cn; Chen, Pi-Min; Wang, Chen [School of Astronautics, Beijing University of Aeronautics and Astronautics, Beijing 100191 (China)

    2014-07-15

    A weakly nonlinear spatial instability of a two-dimensional planar viscous sheet for sinuous disturbances in a co-flowing inviscid gas stream is investigated theoretically, with an emphasis on the effect of the surrounding gas velocity. The solutions of the second-order interface disturbances are derived and the wave deformation has been computed. The results indicate that the second-order surface disturbance of the fundamental sinuous mode is varicose, which causes the thinning and the subsequent breakup of the liquid sheet. The nonlinear behaviors of the planar sheet are quite sensitive to variations in gas-to-liquid velocity ratio. The deviation of the velocity ratio from the value of unity leads to a larger growth rate, a larger second-order initial amplitude, and a shorter breakup length, and therefore enhances the instability. The growth rates predicted by the present nonlinear analysis according to the shortest breakup length are generally smaller than the linear predictions and can better conform to the experimental measures of Barreras et al. [“Linear instability analysis of the viscous longitudinal perturbation on an air-blasted liquid sheets,” Atomization Sprays 11, 139 (2001)]. Furthermore, the wave deformations of the most unstable disturbances are presented. The nonlinear instability of the planar sheet for a fixed velocity difference is performed. An equal increase of the gas and liquid velocity reduces the spatial growth rate and increases the breakup length, but generally has no influences on the second-order initial amplitude and the wavelength of the disturbance.

  5. Temporal evolution of bubble tip velocity in classical Rayleigh-Taylor instability at arbitrary Atwood numbers

    SciTech Connect (OSTI)

    Liu, W. H.; HEDPS and CAPT, Peking University, Beijing 100871 ; Wang, L. F.; Ye, W. H.; Institute of Applied Physics and Computational Mathematics, Beijing 100088; Department of Physics, Zhejiang University, Hangzhou 310027 ; He, X. T.; Institute of Applied Physics and Computational Mathematics, Beijing 100088

    2013-06-15

    In this research, the temporal evolution of the bubble tip velocity in Rayleigh-Taylor instability (RTI) at arbitrary Atwood numbers and different initial perturbation velocities with a discontinuous profile in irrotational, incompressible, and inviscid fluids (i.e., classical RTI) is investigated. Potential models from Layzer [Astrophys. J. 122, 1 (1955)] and perturbation velocity potentials from Goncharov [Phys. Rev. Lett. 88, 134502 (2002)] are introduced. It is found that the temporal evolution of bubble tip velocity [u(t)] depends essentially on the initial perturbation velocity [u(0)]. First, when the u(0)velocity increases smoothly up to the asymptotic velocity (u{sup asp}) or terminal velocity. Second, when C{sup (1)}u{sup asp}?u(0)velocity increases quickly, reaching a maximum velocity and then drops slowly to the u{sup asp}. Third, when C{sup (2)}u{sup asp}?u(0)velocity decays rapidly to a minimum velocity and then increases gradually toward the u{sup asp}. Finally, when u(0)?C{sup (3)}u{sup asp}, the bubble tip velocity decays monotonically to the u{sup asp}. Here, the critical coefficients C{sup (1)},C{sup (2)}, and C{sup (3)}, which depend sensitively on the Atwood number (A) and the initial perturbation amplitude of the bubble tip [h(0)], are determined by a numerical approach. The model proposed here agrees with hydrodynamic simulations. Thus, it should be included in applications where the bubble tip velocity plays an important role, such as the design of the ignition target of inertial confinement fusion where the Richtmyer-Meshkov instability (RMI) can create the seed of RTI with u(0)?u{sup asp}, and stellar formation and evolution in astrophysics where the deflagration wave front propagating outwardly from the star is subject to the combined RMI and RTI.

  6. Localization of Classical Waves I: Acoustic Waves.

    E-Print Network [OSTI]

    Localization of Classical Waves I: Acoustic Waves. Alexander Figotin \\Lambda Department, 1997 Abstract We consider classical acoustic waves in a medium described by a position dependent mass the existence of localized waves, i.e., finite energy solutions of the acoustic equations with the property

  7. 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

  8. GEOPHYSICS, VOL. 56. NO. 2 (FEBRUARY IYYI): P. 208-224. 15 FIGS. Combining wave-equation imaging with traveltime tomography

    E-Print Network [OSTI]

    Pratt, R. Gerhard

    wave (V,s) velocity anomalies can be obtained by applying acoustic wave-equation imaging in two passes slightly better images of the V,] discontinuities than the acoustic wave-equation method. Errors in picking and algorithmic aspects of the method for acoustic and elastic wave equations and applied it to synthetic data

  9. Wave Properties of Isothermal Magneto-Rotational Fluids

    E-Print Network [OSTI]

    M. Sharif; Umber Sheikh

    2009-08-28

    In this paper, the isothermal plasma wave properties in the neighborhood of the pair production region for the Kerr black hole magnetosphere are discussed. We have considered the Fourier analyzed form of the perturbed general relativistic magnetohydrodynamical equations whose determinant leads to a dispersion relation. For the special scenario, the $x$-component of the complex wave vectors are numerically calculated. Respective components of the propagation vector, attenuation vector, phase and group velocities are shown in graphs. We have particularly investigated the existence of a Veselago medium and wave behavior (modes of waves dispersion

  10. Stable operating regime for traveling wave devices

    DOE Patents [OSTI]

    Carlsten, Bruce E. (Los Alamos, NM)

    2000-01-01

    Autophase stability is provided for a traveling wave device (TWD) electron beam for amplifying an RF electromagnetic wave in walls defining a waveguide for said electromagnetic wave. An off-axis electron beam is generated at a selected energy and has an energy noise inherently arising from electron gun. The off-axis electron beam is introduced into the waveguide. The off-axis electron beam is introduced into the waveguide at a second radius. The waveguide structure is designed to obtain a selected detuning of the electron beam. The off-axis electron beam has a velocity and the second radius to place the electron beam at a selected distance from the walls defining the waveguide, wherein changes in a density of the electron beam due to the RF electromagnetic wave are independent of the energy of the electron beam to provide a concomitant stable operating regime relative to the energy noise.

  11. Nonlinear extraordinary wave in dense plasma

    SciTech Connect (OSTI)

    Krasovitskiy, V. B., E-mail: krasovit@mail.ru [Russian Academy of Sciences, Keldysh Institute of Applied Mathematics (Russian Federation); Turikov, V. A. [Russian University of Peoples’ Friendship (Russian Federation)] [Russian University of Peoples’ Friendship (Russian Federation)

    2013-10-15

    Conditions for the propagation of a slow extraordinary wave in dense magnetized plasma are found. A solution to the set of relativistic hydrodynamic equations and Maxwell’s equations under the plasma resonance conditions, when the phase velocity of the nonlinear wave is equal to the speed of light, is obtained. The deviation of the wave frequency from the resonance frequency is accompanied by nonlinear longitudinal-transverse oscillations. It is shown that, in this case, the solution to the set of self-consistent equations obtained by averaging the initial equations over the period of high-frequency oscillations has the form of an envelope soliton. The possibility of excitation of a nonlinear wave in plasma by an external electromagnetic pulse is confirmed by numerical simulations.

  12. Quantum probes of timelike naked singularities in $2+1-$ dimensional power - law spacetimes

    E-Print Network [OSTI]

    O. Gurtug; M. Halilsoy; S. Habib Mazharimousavi

    2015-01-29

    The formation of naked singularities in $2+1-$ dimensional power - law spacetimes in linear Einstein-Maxwell and Einstein-scalar theories sourced by azimuthally symmetric electric field and a self-interacting real scalar field respectively, are considered in view of quantum mechanics. Quantum test fields obeying the Klein-Gordon and Dirac equations are used to probe the classical timelike naked singularities developed at $r=0$. We show that when the classically singular spacetimes probed with scalar waves, the considered spacetimes remains singular. However, the spinorial wave probe of the singularity in the metric of a self-interacting real scalar field remains quantum regular. The notable outcome in this study is that the quantum regularity/singularity can not be associated with the energy conditions.

  13. Scroll Waves Pinned to Moving Heterogeneities

    E-Print Network [OSTI]

    Hua Ke; Zhihui Zhang; Oliver Steinbock

    2014-12-04

    Three-dimensional excitable systems can selforganize vortex patterns that rotate around one-dimensional phase singularities called filaments. In experiments with the Belousov-Zhabotinsky reaction and numerical simulations, we pin these scroll waves to moving heterogeneities and demonstrate the controlled repositioning of their rotation centers. If the pinning site extends only along a portion of the filament, the phase singularity is stretched out along the trajectory of the heterogeneity which effectively writes the singularity into the system. Its trailing end point follows the heterogeneity with a lower velocity. This velocity, its dependence on the placement of the anchor, and the shape of the filament are explained by a curvature flow model.

  14. Modeling of current characteristics of segmented Langmuir probe on DEMETER

    SciTech Connect (OSTI)

    Imtiaz, Nadia; Marchand, Richard [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada)] [Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada); Lebreton, Jean-Pierre [Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), CNRS-Université d'Orléans, Orléans Cedex (France)] [Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), CNRS-Université d'Orléans, Orléans Cedex (France)

    2013-05-15

    We model the current characteristics of the DEMETER Segmented Langmuir probe (SLP). The probe is used to measure electron density and temperature in the ionosphere at an altitude of approximately 700 km. It is also used to measure the plasma flow velocity in the satellite frame of reference. The probe is partitioned into seven collectors: six electrically insulated spherical segments and a guard electrode (the rest of the sphere and the small post). Comparisons are made between the predictions of the model and DEMETER measurements for actual ionospheric plasma conditions encountered along the satellite orbit. Segment characteristics are computed numerically with PTetra, a three-dimensional particle in cell simulation code. In PTetra, space is discretized with an unstructured tetrahedral mesh, thus, enabling a good representation of the probe geometry. The model also accounts for several physical effects of importance in the interaction of spacecraft with the space environment. These include satellite charging, photoelectron, and secondary electron emissions. The model is electrostatic, but it accounts for the presence of a uniform background magnetic field. PTetra simulation results show different characteristics for the different probe segments. The current collected by each segment depends on its orientation with respect to the ram direction, the plasma composition, the magnitude, and the orientation of the magnetic field. It is observed that the presence of light H{sup +} ions leads to a significant increase in the ion current branch of the I-V curves of the negatively polarized SLP. The effect of the magnetic field is demonstrated by varying its magnitude and direction with respect to the reference magnetic field. It is found that the magnetic field appreciably affects the electron current branch of the I-V curves of certain segments on the SLP, whereas the ion current branch remains almost unaffected. PTetra simulations are validated by comparing the computed characteristics and their angular anisotropy with the DEMETER measurements, as simulation results are found to be in good agreement with the measurements.

  15. Particle and Wave: Developing the Quantum Wave Accompanying a Classical Particle

    E-Print Network [OSTI]

    C. L. Herzenberg

    2008-12-04

    The relationship between classical and quantum mechanics is explored in an intuitive manner by the exercise of constructing a wave in association with a classical particle. Using special relativity, the time coordinate in the frame of reference of a moving particle is expressed in terms of the coordinates in the laboratory frame of reference in order to provide an initial spatiotemporal function to work from in initiating the development of a quantum wave. When temporal periodicity is ascribed to the particle, a provisional spatiotemporal function for a particle travelling at constant velocity manifests itself as an running wave characterized by parameters associated with the moving particle. A wave description for bidirectional motion is generated based on an average time coordinate for a combination of oppositely directed elementary running waves, and the resulting spatiotemporal function exhibits wave behavior characteristic of a standing wave. Ascribing directional orientation to the intrinsic periodicity of the particle introduces directional sub-states; variations in the relative number of sub-states as a function of angle in combined states lead to spatially varying magnitudes for the associated waves. Further analysis leads to full mathematical expression for all waves representing free particle motion. A generalization for particles subject to force fields enables us to develop a governing differential equation identical in form to the Schroedinger equation.

  16. Quench propagation velocity for highly stabilized conductors

    SciTech Connect (OSTI)

    Mints, R.G. |; Ogitsu, T. |; Devred, A.

    1995-05-01

    Quench propagation velocity in conductors having a large amount of stabilizer outside the multifilamentary area is considered. It is shown that the current redistribution process between the multifilamentary area and the stabilizer can strongly effect the quench propagation. A criterion is derived determining the conditions under which the current redistribution process becomes significant, and a model of effective stabilizer area is suggested to describe its influence on the quench propagation velocity. As an illustration, the model is applied to calculate the adiabatic quench propagation velocity for a conductor geometry with a multifilamentary area embedded inside the stabilizer.

  17. Hand-held survey probe

    DOE Patents [OSTI]

    Young, Kevin L. (Idaho Falls, ID) [Idaho Falls, ID; Hungate, Kevin E. (Idaho Falls, ID) [Idaho Falls, ID

    2010-02-23

    A system for providing operational feedback to a user of a detection probe may include an optical sensor to generate data corresponding to a position of the detection probe with respect to a surface; a microprocessor to receive the data; a software medium having code to process the data with the microprocessor and pre-programmed parameters, and making a comparison of the data to the parameters; and an indicator device to indicate results of the comparison. A method of providing operational feedback to a user of a detection probe may include generating output data with an optical sensor corresponding to the relative position with respect to a surface; processing the output data, including comparing the output data to pre-programmed parameters; and indicating results of the comparison.

  18. Probe characterization of high-current driven metal plasma in a vacuum-arc rail gun

    SciTech Connect (OSTI)

    Vijayan, T.; Roychowdhury, P.; Venkatramani, N.

    2004-10-15

    The characteristics of metal plasma launched by high-current electric arc in a vacuum-arc rail gun are determined by employing electrical and magnetic probes. These measurements are validated by results from theoretical simulations. The arc coupled nonlinear circuit equations are solved simultaneously with the Newtonian arc motion and revealed the undercritically damped behavior of the arc current identical to the arc-current signal recorded by the Rogowski magnetic probe. Similarly the arc velocity and displacement derived from the signatures of B-dot probes are shown to concur closely with the results of JxB propulsion from simulation. The heating of plasma is formulated in a three-electron population regime with direct arc energy coupling through magnetohydrodynamic, ion-acoustic, Coulomb, and neutral interactions. This results in high temperature (T{sub e}) of hundreds of eV in the arc as revealed by the simulation. Hence T{sub e} of the rapidly cooling and equilibrating plasma that emerged from the muzzle is high around 80-90 eV, which is confirmed by Langmuir electric probe measurements. Density n{sub e} of this metal plasma is shown to be in the range 4x10{sup 21}-6x10{sup 21} m{sup -3} and includes multiple ion charge states. The exit velocity of the plasma measured by a pair of Langmuir probes is close to 2.2x10{sup 6} cm/s and matched well with the arc velocity determined by the B-dot probes and the results from simulation.

  19. Wave-Driven Rotation In Centrifugal Mirrors

    SciTech Connect (OSTI)

    Abraham J. Fetterman and Nathaniel J. Fisch

    2011-03-28

    Centrifugal mirrors use supersonic rotation to provide axial confinement and enhanced stability. Usually the rotation is produced using electrodes, but these electrodes have limited the rotation to the Alfven critical ionization velocity, which is too slow to be useful for fusion. Instead, the rotation could be produced using radio frequency waves. A fixed azimuthal ripple is a simple and efficient wave that could produce rotation by harnessing alpha particle energy. This is an extension of the alpha channeling effect. The alpha particle power and efficiency in a simulated devices is sufficient to produce rotation without external energy input. By eliminating the need for electrodes, this opens new opportunities for centrifugal traps.

  20. Velocity dispersion and upscaling in a laboratory-simulated VSP

    SciTech Connect (OSTI)

    Rio, P.; Mukerji, T.; Mavko, G. [Stanford Univ., CA (United States)] [Stanford Univ., CA (United States); Marion, D. [Elf Aquitaine, Pau (France)] [Elf Aquitaine, Pau (France)

    1996-03-01

    A laboratory and numerical study was conducted to investigate the impact of scale-dependent seismic wave propagation in randomly layered media, as applied to sonic logs, surface seismic, and vertical seismic profiles (VSPs). Analysis of the laboratory results (1) confirmed the wavelength dependence of velocities inferred from traveltimes, (2) indicated that scale effects can introduce traveltime errors when upscaling from logs to surface seismic and VSPs, and (3) illustrated that erroneous VSP interval velocities can result when layer thicknesses are smaller than about one-tenth of the wavelength. A simple approximate recipe is presented for estimating these traveltimes by successively filtering the medium using a running Backus average and ray theory. The scale-dependent dispersion was also predicted well using a more rigorous invariant imbedding formulation. The predicted traveltimes, using the approximate recipe, compare well with the times observed in the laboratory stack of steel and plastic layers and in numerical studies of stratified media. The dispersion curves predicted by the approximate method also show the overall behavior computed with the more rigorous invariant imbedding formulation.

  1. X-ray Imaging of Shock Waves Generated by High-Pressure

    E-Print Network [OSTI]

    Gruner, Sol M.

    , the fuel jets can exceed supersonic speeds and result in gaseous shock waves. High-pressure, high-speed monochromat- ic x-radiography to probe the high-speed fuel sprays and show the generation of shock waves. We studied a high-pressure common-rail diesel injection system typical of that in a passenger car

  2. Nanolithography probes Novel Ultrananocrystalline Diamond Probes for High-

    E-Print Network [OSTI]

    Espinosa, Horacio D.

    excep- tionally well in DPN molecular writing/imaging mode. Furthermore, the integration of UNCD films tasks such as drilling, cutting, or milling.[9,10] The cost of these specialized probes-69451 Weinheim DOI: 10.1002/smll.200500028 small 2005, 1, No. 8-9, 866 ­874 full papers H. D. Espinosa

  3. Modeling velocity dispersion In Gypsy site, Oklahoma

    E-Print Network [OSTI]

    Alsaadan, Sami Ibrahim

    2010-01-01

    Discrepancies in interval velocities estimated from vertical well measurements made with different source central frequencies at Gypsy site could be primarily explained in terms of intrinsic attenuation. Four intervals ...

  4. Recovering Velocity Distributions via Penalized Likelihood

    E-Print Network [OSTI]

    David Merritt

    1996-05-14

    Line-of-sight velocity distributions are crucial for unravelling the dynamics of hot stellar systems. We present a new formalism based on penalized likelihood for deriving such distributions from kinematical data, and evaluate the performance of two algorithms that extract N(V) from absorption-line spectra and from sets of individual velocities. Both algorithms are superior to existing ones in that the solutions are nearly unbiased even when the data are so poor that a great deal of smoothing is required. In addition, the discrete-velocity algorithm is able to remove a known distribution of measurement errors from the estimate of N(V). The formalism is used to recover the velocity distribution of stars in five fields near the center of the globular cluster Omega Centauri.

  5. Explicit dispersion relations for elastic waves in extremely deformed soft matter with application to nearly incompressible and auxetic materials

    E-Print Network [OSTI]

    Pavel Galich; Stephan Rudykh

    2014-12-31

    We analyze the propagation of elastic waves in soft materials subjected to finite deformations. We derive explicit dispersion relations, and apply these results to study elastic wave propagation in (i) nearly incompressible materials such as biological tissues and polymers, and (ii) negative Poisson's ratio or auxetic materials. We find that for nearly incompressible materials transverse wave velocities exhibit strong dependence on direction of propagation and initial strain state, whereas the longitudinal component is not affected significantly until extreme levels of deformations are attained. For highly compressible materials, we show that both pressure and shear wave velocities depend strongly on initial deformation and direction of propagation. When compression is applied, longitudinal wave velocity decreases in positive bulk modulus materials, and increases for negative bulk modulus materials; this is regardless the direction of wave prorogation. We demonstrate that finite deformations influence elastic wave propagation through combinations of induced effective compressibility and stiffness.

  6. SHEAR-WAVE SOURCED 3-D VSP IMAGING OF TIGHT-GAS SANDSTONES IN RULISON FIELD, COLORADO

    E-Print Network [OSTI]

    1 #12;SHEAR-WAVE SOURCED 3-D VSP IMAGING OF TIGHT-GAS SANDSTONES IN RULISON FIELD, COLORADO heavily on understanding the distribution of sandstone bodies in the subsurface. Shear-wave sourced 3-D was applied to the shear- wave reflection data. A geologically-constrained migration-velocity model

  7. Turbulent combined wave-current boundary layer model for application in coastal waters

    E-Print Network [OSTI]

    Humbyrd, Chelsea Joy

    2012-01-01

    Accurately predicting transport processes, including sediment transport, in the coastal environment is impossible without correct current velocity and shear stress information. A combined wave-current boundary layer theory ...

  8. Observations and modeling of wave-acceleration-induced sediment transport in the surfzone

    E-Print Network [OSTI]

    Hoefel, Fernanda Gemael, 1973-

    2004-01-01

    Onshore sediment transport and sandbar migration are important to the morphological evolution of beaches, but are not understood well. Here, a new model that accounts for accelerations of wave-orbital velocities predicts ...

  9. Modeling fault-zone guided waves of microearthquakes in a geothermal...

    Open Energy Info (EERE)

    the identification and modeling of such guided waves is an effective tool to locate fracture-induced, low-velocity fault-zone structures in geothermal fields. Authors Lou, M.;...

  10. Gravitational waves and gamma-ray bursts

    E-Print Network [OSTI]

    Alessandra Corsi; for the LIGO Scientific Collaboration; for the Virgo Collaboration

    2012-05-11

    Gamma-Ray Bursts are likely associated with a catastrophic energy release in stellar mass objects. Electromagnetic observations provide important, but indirect information on the progenitor. On the other hand, gravitational waves emitted from the central source, carry direct information on its nature. In this context, I give an overview of the multi-messenger study of gamma-ray bursts that can be carried out by using electromagnetic and gravitational wave observations. I also underline the importance of joint electromagnetic and gravitational wave searches, in the absence of a gamma-ray trigger. Finally, I discuss how multi-messenger observations may probe alternative gamma-ray burst progenitor models, such as the magnetar scenario.

  11. Landau damping of Langmuir waves in non-Maxwellian plasmas

    SciTech Connect (OSTI)

    Ouazene, M.; Annou, R.

    2011-11-15

    As free electrons move in the nearest neighbour ion's potential well, the equilibrium velocity departs from Maxwell distribution. The effect of the non-Maxwellian velocity distribution function (NMVDF) on many properties of the plasma such as the transport coefficients, the kinetic energy, and the degree of ionization is found to be noticeable. A correction to the Langmuir wave dispersion relation is proved to arise due to the NMVDF as well [Phys. Plasmas 17, 052105 (2010)]. The study is extended hereafter to include the effect of NMVDF on the Landau damping of Langmuir wave.

  12. Extracting Fish and Water Velocity from Doppler Profiler Data

    E-Print Network [OSTI]

    deYoung, Brad

    Extracting Fish and Water Velocity from Doppler Profiler Data ĺ Ð 1 ¸ Ö Ò ×¹ Ò ÝÖ¹Ê Ò 2 1 processing algo- rithms normally used to extract water velocity. We present an alternative method for velocity homogeneity precludes the extraction of fish velocities. Water velocities can sometimes still

  13. Wave Energy Basics

    Broader source: Energy.gov [DOE]

    Wave energy technologies extract energy directly from surface waves or from pressure fluctuations below the surface. Renewable energy analysts believe there is enough energy in ocean waves to provide up to 2 terawatts of electricity.

  14. Wave Control Introduction

    E-Print Network [OSTI]

    Wirosoetisno, Djoko

    focussing: in crossing seas due to coastal or submarine convergences. Moreover, (rogue) wave energy devices maker to create the highest rogue wave? geometry and dynamo in a new rogue wave energy device? maximum

  15. Nuclear Physics with electroweak probes

    E-Print Network [OSTI]

    Giampaolo Co'

    2004-11-30

    The last few years activity of the Italian community concerning nuclear physics with electroweak probes is reviewed.Inclusive quasi-elastic electron-scattering, photon end electron induced one- and two-nucleon emission are considered. The scattering of neutrinos off nuclei in the quasi-elastic region is also discussed.

  16. Hard Probes 2012: Experimental Summary

    E-Print Network [OSTI]

    J. Schukraft

    2012-10-17

    The 5th international Conference on Hard and Electromagnetic Probes in High-Energy Nuclear Collisions was held in May 2012 in Cagliari, Italy. This contribution summarises some of the experimental highlights presented at the meeting, concentrating on new results from LHC and RHIC on parton energy loss ('jet-quenching') and heavy quark meson production ('quarkonia suppression').

  17. Nuclear Physics with Electroweak Probes

    E-Print Network [OSTI]

    Omar Benhar

    2009-02-26

    In recent years, the italian theoretical Nuclear Physics community has played a leading role in the development of a unified approach, allowing for a consistent and fully quantitative description of the nuclear response to electromagnetic and weak probes. In this paper I review the main achievements in both fields, point out some of the open problems, and outline the most promising prospects.

  18. Experimental investigation on structures and velocity of liquid jets in a supersonic crossflow

    SciTech Connect (OSTI)

    Wang, Zhen-guo Wu, Liyin; Li, Qinglian; Li, Chun

    2014-09-29

    Particle image velocimetry was applied in the study focusing on the structure and velocity of water jets injected into a Ma?=?2.1 crossflow. The instantaneous structures of the jet, including surface waves in the near-injector region and vortices in the far-field, were visualized clearly. Spray velocity increases rapidly to 66% of the mainstream velocity in the region of x/d?velocity grows slowly in the far-field region, where the liquid inside the spray is accelerated mainly by the continuous driven force provided by the mainstream with the gas-liquid shear. The injection and atomization of liquid jet in a supersonic crossflow serves as a foundation of scramjet combustion process, by affecting the combustion efficiency and some other performances. With various forces acting on the liquid jet (Mashayek et al. [AIAA J. 46, 2674–2686 (2008)] and Wang et al. [AIAA J. 50, 1360–1366 (2012)]), the atomization process involves very complex flow physics. These physical processes include strong vortical structures, small-scale wave formation, stripping of small droplets from the jet surface, formations of ligaments, and droplets with a wide range of sizes.

  19. 4794 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 56, NO. 10, OCTOBER 2008 Seismic Velocity and Polarization Estimation

    E-Print Network [OSTI]

    Nehorai, Arye

    4794 IEEE TRANSACTIONS ON SIGNAL PROCESSING, VOL. 56, NO. 10, OCTOBER 2008 Seismic Velocity the shape pa- rameters of seismic wavefields using linear arrays of three-compo- nent (3C) vector sensors with uncertain acquisition geometry. The goal is to separate the different seismic waves, which is of prac- tical

  20. Your Mission: 1) Create a Tsunami in a box! Measure its velocity. 2) Analyze tsunami hazards and past tsunami data

    E-Print Network [OSTI]

    Smith-Konter, Bridget

    Your Mission: 1) Create a Tsunami in a box! Measure its velocity. 2) Analyze tsunami hazards and past tsunami data Your Supplies: Plastic tub (outside) Sand and water (outside) Board with handle will be using this as a marker for timing the arrival of the tsunami wave. Length of the tub = _______________ m

  1. PHYSICAL REVIEW E 84, 056408 (2011) Doppler measurement of implosion velocity in fast Z-pinch x-ray sources

    E-Print Network [OSTI]

    Starobinets, Alexander

    2011-01-01

    in the sun [1], waves in the solar corona [2], the wobble of stars perturbed by exoplanets [3,4], and binary of velocity is important to inferring the plasma kinetic energy, which can be the primary storage reservoir of j × B work accumulated over 100 ns during implosion and then provide plasma heating when thermalized

  2. Gyrokinetic simulation of momentum transport with residual stress from diamagnetic level velocity shears

    SciTech Connect (OSTI)

    Waltz, R. E.; Staebler, G. M.; Solomon, W. M.

    2011-04-15

    Residual stress refers to the remaining toroidal angular momentum (TAM) flux (divided by major radius) when the shear in the equilibrium fluid toroidal velocity (and the velocity itself) vanishes. Previously [Waltz et al., Phys. Plasmas 14, 122507 (2007); errata 16, 079902 (2009)], we demonstrated with GYRO [Candy and Waltz, J. Comp. Phys. 186, 545 (2003)] gyrokinetic simulations that TAM pinching from (ion pressure gradient supported or diamagnetic level) equilibrium ExB velocity shear could provide some of the residual stress needed to support spontaneous toroidal rotation against normal diffusive loss. Here we show that diamagnetic level shear in the intrinsic drift wave velocities (or ''profile shear'' in the ion and electron density and temperature gradients) provides a comparable residual stress. The individual signed contributions of these small (rho-star level) ExB and profile velocity shear rates to the turbulence level and (rho-star squared) ion energy transport stabilization are additive if the rates are of the same sign. However because of the additive stabilization effect, the contributions to the small (rho-star cubed) residual stress is not always simply additive. If the rates differ in sign, the residual stress from one can buck out that from the other (and in some cases reduce the stabilization.) The residual stress from these diamagnetic velocity shear rates is quantified by the ratio of TAM flow to ion energy (power) flow (M/P) in a global GYRO core simulation of a ''null'' toroidal rotation DIII-D [Mahdavi and Luxon, Fusion Sci. Technol. 48, 2 (2005)] discharge by matching M/P profiles within experimental uncertainty. Comparison of global GYRO (ion and electron energy as well as particle) transport flow balance simulations of TAM transport flow in a high-rotation DIII-D L-mode quantifies and isolates the ExB shear and parallel velocity (Coriolis force) pinching components from the larger ''diffusive'' parallel velocity shear driven component and the much smaller profile shear residual stress component.

  3. Velocity dependence of friction of confined polymers

    E-Print Network [OSTI]

    I. M. Sivebaek; V. N. Samoilov; B. N. J. Persson

    2009-11-18

    We present molecular dynamics friction calculations for confined hydrocarbon solids with molecular lengths from 20 to 1400 carbon atoms. Two cases are considered: (a) polymer sliding against a hard substrate, and (b) polymer sliding on polymer. We discuss the velocity dependence of the frictional shear stress for both cases. In our simulations, the polymer films are very thin (approx. 3 nm), and the solid walls are connected to a thermostat at a short distance from the polymer slab. Under these circumstances we find that frictional heating effects are not important, and the effective temperature in the polymer film is always close to the thermostat temperature. In the first setup (a), for hydrocarbons with molecular lengths from 60 to 1400 carbon atoms, the shear stresses are nearly independent of molecular length, but for the shortest hydrocarbon C20H42 the frictional shear stress is lower. In all cases the frictional shear stress increases monotonically with the sliding velocity. For polymer sliding on polymer [case (b)] the friction is much larger, and the velocity dependence is more complex. For hydrocarbons with molecular lengths from 60 to 140 C-atoms, the number of monolayers of lubricant increases (abruptly) with increasing sliding velocity (from 6 to 7 layers), leading to a decrease of the friction. Before and after the layering transition, the frictional shear stresses are nearly proportional to the logarithm of sliding velocity. For the longest hydrocarbon (1400 C-atoms) the friction shows no dependence on the sliding velocity, and for the shortest hydrocarbon (20 C-atoms) the frictional shear stress increases nearly linearly with the sliding velocity.

  4. Experimental study of internal wave generation by convection in water

    E-Print Network [OSTI]

    Bars, Michael Le; Perrard, Stéphane; Ribeiro, Adolfo; Rodet, Laetitia; Aurnou, Jonathan M; Gal, Patrice Le

    2015-01-01

    We experimentally investigate the dynamics of water cooled from below at 0^oC and heated from above. Taking advantage of the unusual property that water's density maximum is at about 4^oC, this set-up allows us to simulate in the laboratory a turbulent convective layer adjacent to a stably stratified layer, which is representative of atmospheric and stellar conditions. High precision temperature and velocity measurements are described, with a special focus on the convectively excited internal waves propagating in the stratified zone. Most of the convective energy is at low frequency, and corresponding waves are localized to the vicinity of the interface. However, we show that some energy radiates far from the interface, carried by shorter horizontal wavelength, higher frequency waves. Our data suggest that the internal wave field is passively excited by the convective fluctuations, and the wave propagation is correctly described by the dissipative linear wave theory.

  5. Hydrodynamic Waves in an Anomalous Charged Fluid

    E-Print Network [OSTI]

    Abbasi, Navid; Rezaei, Zahra

    2015-01-01

    We study the collective excitations in a relativistic fluid with an anomalous conserved charge. In $3+1$ dimensions, in addition to two ordinary sound modes we find two propagating modes in presence of an external magnetic field: one with a velocity proportional to the coefficient of gauge-gravitational anomaly coefficient and the other with a velocity which depends on both chiral anomaly and the gauge gravitational anomaly coefficients. While the former is the Chiral Alfv\\'en wave recently found in arXiv:1505.05444, the latter is a new type of collective excitations originated from the density fluctuations. We refer to these modes as the Type-M and Type-D chiral Alfv\\'en waves respectively. We show that the Type-M Chiral Alfv\\'en mode is split into two chiral Alfv\\'en modes when taking into account the effect of dissipation processes in the fluid. In 1+1 dimensions we find only one propagating mode associated with the anomalous effects. We explicitly compute the velocity of this wave and show that in contras...

  6. DETERMINATION OF NON-THERMAL VELOCITY DISTRIBUTIONS FROM SERTS LINEWIDTH OBSERVATIONS

    SciTech Connect (OSTI)

    Coyner, Aaron J. [Department of Physics, Catholic University of America, 620 Michigan Avenue, Washington, DC 20064 (United States); Davila, Joseph M., E-mail: aaron.j.coyner@nasa.gov [Code 671, NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2011-12-01

    Non-thermal velocities obtained from the measurement of coronal Extreme Ultraviolet (EUV) linewidths have been consistently observed in solar EUV spectral observations and have been theorized to result from many plausible scenarios including wave motions, turbulence, or magnetic reconnection. Constraining these velocities can provide a physical limit for the available energy resulting from unresolved motions in the corona. We statistically determine a series of non-thermal velocity distributions from linewidth measurements of 390 emission lines from a wide array of elements and ionization states observed during the Solar Extreme Ultraviolet Research Telescope and Spectrograph 1991-1997 flights covering the spectral range 174-418 A and a temperature range from 80,000 K to 12.6 MK. This sample includes 248 lines from active regions, 101 lines from quiet-Sun regions, and 41 lines were observed from plasma off the solar limb. We find a strongly peaked distribution corresponding to a non-thermal velocity of 19-22 km s{sup -1} in all three of the quiet-Sun, active region, and off-limb distributions. For the possibility of Alfven wave resonance heating, we find that velocities in the core of these distributions do not provide sufficient energy, given typical densities and magnetic field strengths for the coronal plasma, to overcome the estimated coronal energy losses required to maintain the corona at the typical temperatures working as the sole mechanism. We find that at perfect efficiency 50%-60% of the needed energy flux can be produced from the non-thermal velocities measured.

  7. IBM Probes Material Capabilities at the ALS

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

    IBM Probes Material Capabilities at the ALS IBM Probes Material Capabilities at the ALS Print Wednesday, 12 February 2014 11:05 Vanadium dioxide, one of the few known materials...

  8. Cantilevered probe detector with piezoelectric element

    DOE Patents [OSTI]

    Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

    2014-04-29

    A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

  9. Cantilevered probe detector with piezoelectric element

    DOE Patents [OSTI]

    Adams, Jesse D; Sulchek, Todd A; Feigin, Stuart C

    2013-04-30

    A disclosed chemical detection system for detecting a target material, such as an explosive material, can include a cantilevered probe, a probe heater coupled to the cantilevered probe, and a piezoelectric element disposed on the cantilevered probe. The piezoelectric element can be configured as a detector and/or an actuator. Detection can include, for example, detecting a movement of the cantilevered probe or a property of the cantilevered probe. The movement or a change in the property of the cantilevered probe can occur, for example, by adsorption of the target material, desorption of the target material, reaction of the target material and/or phase change of the target material. Examples of detectable movements and properties include temperature shifts, impedance shifts, and resonant frequency shifts of the cantilevered probe. The overall chemical detection system can be incorporated, for example, into a handheld explosive material detection system.

  10. Spring Semester, Course Title: Scanned Probe Techniques

    E-Print Network [OSTI]

    Sherrill, David

    : a fundamental understanding of the theoretical underpinnings behind each scanned probe technique Scanning Probe Methods (Vol. 1-13) ­ Bharat Bhushan, ed. Springer Handbook of Nanotechnology - Bharat Roughness o Representative applications in surface science HOPG Silicon Screw dislocations Liquid

  11. Geometrical vs wave optics under gravitational waves

    E-Print Network [OSTI]

    Raymond Angélil; Prasenjit Saha

    2015-05-20

    We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely null geodesics and Maxwell's equations, or, geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics - rather than solving Maxwell's equations directly for the fields, as in most previous approaches - we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic fields all experience the same phase modulation. Applying such a phase modulation to a superposition of plane waves corresponding to a Gaussian wave packet leads to time delays.

  12. Coherent cooling of atoms in a frequency-modulated standing laser wave: Wave function and stochastic trajectory approaches

    SciTech Connect (OSTI)

    Argonov, V. Yu.

    2014-11-15

    The wave function of a moderately cold atom in a stationary near-resonant standing light wave delocalizes very fast due to wave packet splitting. However, we show that frequency modulation of the field can suppress packet splitting for some atoms whose specific velocities are in a narrow range. These atoms remain localized in a small space for a long time. We demonstrate and explain this effect numerically and analytically. We also demonstrate that the modulated field can not only trap but also cool the atoms. We perform a numerical experiment with a large atomic ensemble having wide initial velocity and energy distributions. During the experiment, most of atoms leave the wave while the trapped atoms have a narrow energy distribution.

  13. Investigation of Wave Energy Converter Effects on Wave Fields: A Modeling Sensitivity Study in Monterey Bay CA.

    SciTech Connect (OSTI)

    Roberts, Jesse D.; Grace Chang; Jason Magalen; Craig Jones

    2014-08-01

    A n indust ry standard wave modeling tool was utilized to investigate model sensitivity to input parameters and wave energy converter ( WEC ) array deploym ent scenarios. Wave propagation was investigated d ownstream of the WECs to evaluate overall near - and far - field effects of WEC arrays. The sensitivity study illustrate d that b oth wave height and near - bottom orbital velocity we re subject to the largest pote ntial variations, each decreas ed in sensitivity as transmission coefficient increase d , as number and spacing of WEC devices decrease d , and as the deployment location move d offshore. Wave direction wa s affected consistently for all parameters and wave perio d was not affected (or negligibly affected) by varying model parameters or WEC configuration .

  14. HYBRID COSMOLOGICAL SIMULATIONS WITH STREAM VELOCITIES

    SciTech Connect (OSTI)

    Richardson, Mark L. A.; Scannapieco, Evan [School of Earth and Space Exploration, Arizona State University, Tempe, AZ 85287 (United States); Thacker, Robert J. [Department of Astronomy and Physics, Saint Mary's University, Halifax, B3H 3C3 (Canada)

    2013-07-10

    In the early universe, substantial relative ''stream'' velocities between the gas and dark matter arise due to radiation pressure and persist after recombination. To assess the impact of these velocities on high-redshift structure formation, we carry out a suite of high-resolution adaptive mesh refinement (AMR) cosmological simulations, which use smoothed particle hydrodynamic data sets as initial conditions, converted using a new tool developed for this work. These simulations resolve structures with masses as small as a few 100 M{sub Sun }, and we focus on the 10{sup 6} M{sub Sun} ''mini-halos'' in which the first stars formed. At z Almost-Equal-To 17, the presence of stream velocities has only a minor effect on the number density of halos below 10{sup 6} M{sub Sun }, but it greatly suppresses gas accretion onto all halos and the dark matter structures around them. Stream velocities lead to significantly lower halo gas fractions, especially for Almost-Equal-To 10{sup 5} M{sub Sun} objects, an effect that is likely to depend on the orientation of a halo's accretion lanes. This reduction in gas density leads to colder, more compact radial profiles, and it substantially delays the redshift of collapse of the largest halos, leading to delayed star formation and possibly delayed reionization. These many differences suggest that future simulations of early cosmological structure formation should include stream velocities to properly predict gas evolution, star formation, and the epoch of reionization.

  15. Probing Light Dark Matter via Evaporation from the Sun

    E-Print Network [OSTI]

    Chris Kouvaris

    2015-06-13

    Dark matter particles can be captured by the sun with rates that depend on the dark matter mass and the DM-nucleon cross section. However, for masses below $\\sim 3.3$ GeV, the captured dark matter particles evaporate, leading to an equilibrium where the rate of captured particles is equal to the rate of evaporating ones. Unlike dark matter particles from the halo, the evaporating dark matter particles have velocities that are not limited to values below the escape velocity of the galaxy. Despite the fact that high velocities are exponentially suppressed, I demonstrate here that current underground detectors have the possibility to probe/constrain low dark matter parameter space by (not)-observing the high energy tail of the evaporating dark matter particles from the sun. I also show that the functional form of the differential rate of counts with respect to the recoil energy in earth based detectors can identify precisely the mass and the cross section of the dark matter particle in this case.

  16. New constraints on the upper mantle structure of the Slave craton from Rayleigh wave inversion

    E-Print Network [OSTI]

    Rondenay, Stephane

    New constraints on the upper mantle structure of the Slave craton from Rayleigh wave inversion Chin recorded by the POLARIS broadband seismic network and the Yellowknife array. Phase velocities obtained of its high degree of mantle depletion. The one-dimensional inversion of phase velocities yields high

  17. Propagation of a solitary fission wave A. G. Osborne, G. D. Recktenwald, and M. R. Deinerta)

    E-Print Network [OSTI]

    Deinert, Mark

    , or oscillatory over the interval of interest.7 Solutions for the propagation velocity of reaction-diffusion waves diffusion coefficient and a is the inverse of the neutron velocity. The reaction term V/ takes 24 February 2012; accepted 5 June 2012; published online 22 June 2012) Reaction-diffusion phenomena

  18. VELOCITY-SHEAR-INDUCED MODE COUPLING IN THE SOLAR ATMOSPHERE AND SOLAR WIND: IMPLICATIONS FOR PLASMA HEATING AND MHD TURBULENCE

    SciTech Connect (OSTI)

    Hollweg, Joseph V.; Chandran, Benjamin D. G.; Kaghashvili, Edisher Kh. E-mail: ekaghash@aer.com

    2013-06-01

    We analytically consider how velocity shear in the corona and solar wind can cause an initial Alfven wave to drive up other propagating signals. The process is similar to the familiar coupling into other modes induced by non-WKB refraction in an inhomogeneous plasma, except here the refraction is a consequence of velocity shear. We limit our discussion to a low-beta plasma, and ignore couplings into signals resembling the slow mode. If the initial Alfven wave is propagating nearly parallel to the background magnetic field, then the induced signals are mainly a forward-going (i.e., propagating in the same sense as the original Alfven wave) fast mode, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; both signals are compressive and subject to damping by the Landau resonance. For an initial Alfven wave propagating obliquely with respect to the magnetic field, the induced signals are mainly forward- and backward-going fast modes, and a driven signal propagating like a forward-going Alfven wave but polarized like the fast mode; these signals are all compressive and subject to damping by the Landau resonance. A backward-going Alfven wave, thought to be important in the development of MHD turbulence, is also produced, but it is very weak. However, we suggest that for oblique propagation of the initial Alfven wave the induced fast-polarized signal propagating like a forward-going Alfven wave may interact coherently with the initial Alfven wave and distort it at a strong-turbulence-like rate.

  19. Discretising the velocity distribution for directional dark matter experiments

    E-Print Network [OSTI]

    Kavanagh, Bradley J

    2015-01-01

    Dark matter (DM) direct detection experiments which are directionally-sensitive may be the only method of probing the full velocity distribution function (VDF) of the Galactic DM halo. We present an angular basis for the DM VDF which can be used to parametrise the distribution in order to mitigate astrophysical uncertainties in future directional experiments and extract information about the DM halo. This basis consists of discretising the VDF in a series of angular bins, with the VDF being only a function of the DM speed $v$ within each bin. In contrast to other methods, such as spherical harmonic expansions, the use of this basis allows us to guarantee that the resulting VDF is everywhere positive and therefore physical. We present a recipe for calculating the event rates corresponding to the discrete VDF for an arbitrary number of angular bins $N$ and investigate the discretisation error which is introduced in this way. For smooth, Standard Halo Model-like distribution functions, only $N=3$ angular bins ar...

  20. PROTOSTELLAR JETS ENCLOSED BY LOW-VELOCITY OUTFLOWS (Journal...

    Office of Scientific and Technical Information (OSTI)

    PROTOSTELLAR JETS ENCLOSED BY LOW-VELOCITY OUTFLOWS Citation Details In-Document Search Title: PROTOSTELLAR JETS ENCLOSED BY LOW-VELOCITY OUTFLOWS A protostellar jet and outflow...

  1. RESEARCH ARTICLE Minimization of divergence error in volumetric velocity

    E-Print Network [OSTI]

    Marusic, Ivan

    RESEARCH ARTICLE Minimization of divergence error in volumetric velocity measurements Volumetric velocity measurements taken in incompressible fluids are typically hindered by a nonzero

  2. Sound velocity bound and neutron stars

    E-Print Network [OSTI]

    Paulo F. Bedaque; Andrew W. Steiner

    2015-01-25

    It has been conjectured that the velocity of sound in any medium is smaller than the velocity of light in vacuum divided by $\\sqrt{3}$. Simple arguments support this bound in non-relativistic and/or weakly coupled theories. The bound has been demonstrated in several classes of strongly coupled theories with gravity duals and is saturated only in conformal theories. We point out that the existence of neutron stars with masses around two solar masses combined with the knowledge of the equation of state of hadronic matter at "low" densities is in strong tension with this bound.

  3. Migration velocity analysis for TI media in the presence of quadratic lateral velocity variation

    E-Print Network [OSTI]

    Tsvankin, Ilya

    of lateral heteroge- neity on image gathers obtained after prestack depth migration and found that quadratic that application of prestack depth migration (PSDM) with anisotropic MVA yields sig- nificantly improved imagesMigration velocity analysis for TI media in the presence of quadratic lateral velocity variation

  4. Augmented Geophysical Data Interpretation Through Automated Velocity Picking in Semblance Velocity Images

    E-Print Network [OSTI]

    Whitley, Darrell

    Augmented Geophysical Data Interpretation Through Automated Velocity Picking in Semblance Velocity on the surface. Currently, geophysicists spend hours, days or weeks in front of monitors tracing curves on images of these cor- respond to the bright spots selected by the geophysicist. Next, a combinatorial optimization

  5. Alfven Wave-Driven Supernova Explosion

    E-Print Network [OSTI]

    T. K. Suzuki; K. Sumiyoshi; S. Yamada

    2007-12-06

    We investigate the role of Alfven waves in the core-collapse supernova (SN) explosion. We assume that Alfven waves are generated by convections inside a proto-neutron star (PNS) and emitted from its surface. Then these waves propagate outwards, dissipate via nonlinear processes, and heat up matter around a stalled prompt shock. To quantitatively assess the importance of this process for the revival of the stalled shock, we perform 1D time-dependent hydrodynamical simulations, taking into account the heating via the dissipation of Alfven waves that propagate radially outwards along open flux tubes. We show that the shock revival occurs if the surface field strength is larger than ~2e15 G and if the amplitude of velocity fluctuation at the PNS surface is larger than 20% of the local sound speed. Interestingly, the Alfven wave mechanism is self-regulating in the sense that the explosion energy is not very sensitive to the surface field strength and initial amplitude of Alfven waves as long as they are larger than the threshold values given above.

  6. A Nonlocal Formulation of Rotational Water Waves

    E-Print Network [OSTI]

    Anthony C. L Ashton; A. S. Fokas

    2011-07-29

    The classical equations of irrotational water waves have recently been reformulated as a system of two equations, one of which is an explicit non-local equation for the wave height and for the velocity potential evaluated on the free surface. Here, in the two dimensional case, (a) we generalise the relevant formulation to the case of constant vorticity, as well as to the case where the free surface is described by a multi-valued function; (b) in the case of travelling waves we derive an upper bound for the free surface; (c) in the case of constant vorticity we construct a sequence of nearly Hamiltonian systems which provide an approximation in the asymptotic limit of certain physical small parameters. In particular, the explicit dependence of the vorticity on the coefficients of the KdV equation is clarified. Also, in the irrotational case we extend the formalism to n>2 dimensions and analyse rigorously the linear limit of these equations.

  7. Wave turbulence served up on a plate

    E-Print Network [OSTI]

    Pablo Cobelli; Philippe Petitjeans; Agnes Maurel; Vincent Pagneux; Nicolas Mordant

    2009-10-28

    Wave turbulence in a thin elastic plate is experimentally investigated. By using a Fourier transform profilometry technique, the deformation field of the plate surface is measured simultaneously in time and space. This enables us to compute the wavevector-frequency Fourier ($\\mathbf k, \\omega$) spectrum of the full space-time deformation velocity. In the 3D ($\\mathbf k, \\omega$) space, we show that the energy of the motion is concentrated on a 2D surface that represents a nonlinear dispersion relation. This nonlinear dispersion relation is close to the linear dispersion relation. This validates the usual wavenumber-frequency change of variables used in many experimental studies of wave turbulence. The deviation from the linear dispersion, which increases with the input power of the forcing, is attributed to weak non linear effects. Our technique opens the way for many new extensive quantitative comparisons between theory and experiments of wave turbulence.

  8. Interaction engineering for environmental probing

    E-Print Network [OSTI]

    M. Paternostro; S. Bose; M. S. Kim

    2007-06-04

    We study the conditions for the probing of an environment affecting one party of a bipartite system of interacting objects by measurements operated only on the other element. We show that entanglement plays no crucial role in such an environment-characterization. On the other hand, if an interaction is established between the two parties, information can be reliably gathered. This result holds for both discrete and continuous variables and helps in the interpretation of recent experiments addressing the properties of mesoscopic objects.

  9. Interaction engineering for environmental probing

    E-Print Network [OSTI]

    Paternostro, M; Kim, M S

    2007-01-01

    We study the conditions for the probing of an environment affecting one party of a bipartite system of interacting objects by measurements operated only on the other element. We show that entanglement plays no crucial role in such an environment-characterization. On the other hand, if an interaction is established between the two parties, information can be reliably gathered. This result holds for both discrete and continuous variables and helps in the interpretation of recent experiments addressing the properties of mesoscopic objects.

  10. Optical probe with reference fiber

    DOE Patents [OSTI]

    Da Silva, Luiz B. (Danville, CA); Chase, Charles L. (Dublin, CA)

    2006-03-14

    A system for characterizing tissue includes the steps of generating an emission signal, generating a reference signal, directing the emission signal to and from the tissue, directing the reference signal in a predetermined manner relative to the emission signal, and using the reference signal to compensate the emission signal. In one embodiment compensation is provided for fluctuations in light delivery to the tip of the probe due to cable motion.

  11. pH Meter probe assembly

    DOE Patents [OSTI]

    Hale, Charles J. (San Jose, CA)

    1983-01-01

    An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe.

  12. pH Meter probe assembly

    DOE Patents [OSTI]

    Hale, C.J.

    1983-11-15

    An assembly for mounting a pH probe in a flowing solution, such as a sanitary sewer line, which prevents the sensitive glass portion of the probe from becoming coated with grease, oil, and other contaminants, whereby the probe gives reliable pH indication over an extended period of time. The pH probe assembly utilizes a special filter media and a timed back-rinse feature for flushing clear surface contaminants of the filter. The flushing liquid is of a known pH and is utilized to check performance of the probe. 1 fig.

  13. Big Flippin' Wave Science

    E-Print Network [OSTI]

    California at Santa Barbara, University of

    Verdes, Campus Point, Coal Oil Point (Sands) Waves propagate perpendicular to isobaths (lines of constant

  14. Water Waves Roger Grimshaw

    E-Print Network [OSTI]

    Water Waves Roger Grimshaw May 7, 2003 Abstract A short review of the theory of weakly nonlinear water waves, prepared for the forthcoming Encyclopedia of Nonlinear Science 1 Introduction Water waves nonlinear waves. Throughout the theory is based on the traditional assumptions that water is inviscid

  15. EEDF measurements by gridded probes

    SciTech Connect (OSTI)

    Annaratone, B.M.; Farahat, S.I.; Allen, J.E.

    1995-12-31

    A knowledge of the plasma parameters and the energy of the electrons can greatly improve the role of plasma in applications such as plasma chemistry, processing of materials, fight production and laser technology. With the development of data acquisition techniques the calculation of the EEDF from experimentally obtained probe characteristics has become increasingly utilised. The geometry of the probe is taken in account in deriving the plasma density from the ion collection part of the I-V characteristic. The electrons are ignored taking the characteristic at high negative potentials and the curves are interpreted following the radial or the orbital motion theory. Instead when the electron distribution is the object of the investigation a linearised ion contribution is often subtracted in the part of the characteristic where the ion current curvature is highest. In order to make a quantitative estimate we refer to the numerical work of Nairn et al. who calculate the ion current in radial motion for an extended range of the ratio motion for an extended range of the ratio r{sub p}/{lambda}{sub D} (radius of the cylindrical probe over the Debye distance). Radial motion has been proved to be applicable in most of the plasmas used for processing. We can compare the derivative of the ion current with respect to the voltage with the derivative of the electron retardation current which, in the normalization used, depends on the ratio of the ion to the electron mass. Let us consider, for example, a typical probe used for EEDF measurements, with r{sub p}/{lambda}{sub D} = 1 in Argon. We can see that the ion slope is already 14% of the electron slope for a floating potential only 3.6 kT{sub e}/e negative with respect to the plasma. Lighter gases, for the same voltage, will show a greater error. This work proposes the gridded probe as a reliable method to extend the measurements of the EEDF to values well negative with respect to the floating potential.

  16. Seismic Ground Motions from a Bolide Shock Wave Charles A. Langston

    E-Print Network [OSTI]

    Langston, Charles A.

    -surface layer with low P wave (~0.25 km/s) and S wave (~0.125 km/s) velocities consistent with previously published profiling results in unconsolidated Mississippi embayment sediments. Ground motions are generally/04/2003 ~3:50 UT). Some observers also reported that the bolide was accompanied by a sonic boom and residents

  17. EFFECT OF IMMISCIBLE LIQUID CONTAMINANTS ON P-WAVE TRANSMISSION THROUGH NATURAL AQUIFER SAMPLES

    E-Print Network [OSTI]

    Ajo-Franklin, Jonathan

    EFFECT OF IMMISCIBLE LIQUID CONTAMINANTS ON P-WAVE TRANSMISSION THROUGH NATURAL AQUIFER SAMPLES Jil the effect of non-aqueous phase liquid (NAPL) contaminants on P-wave velocity and attenuation attenuation, which may be due to lithology and/or contaminants (NAPL or gas phase). Intact core was obtained

  18. Emission of Inertial Waves by Baroclinically Unstable Flows: Laboratory Experiments with Altimetric Imaging Velocimetry

    E-Print Network [OSTI]

    the dispersion relation for the inertial waves. The energy of the waves is small compared to the energy, or the "gradient wind" velocity with very high spatial resolution (typically several million vectors) limited largely by the pixel resolution of the available imaging sensors. The technique is particularly suited

  19. Propagation in a kinetic reaction-transport equation: travelling waves and accelerating fronts

    E-Print Network [OSTI]

    Calvez, Vincent

    describes particles moving according to a velocity-jump process, and proliferating thanks to a reaction termPropagation in a kinetic reaction-transport equation: travelling waves and accelerating fronts the existence and stability of travelling wave solutions of a kinetic reaction- transport equation. The model

  20. Shock-Wave Attenuation and Energy-Dissipation Potential of Granular Materials

    E-Print Network [OSTI]

    Grujicic, Mica

    Shock-Wave Attenuation and Energy-Dissipation Potential of Granular Materials Mica Grujicic, B this approach, both compression shocks and decompression waves are treated as (stress, specific volume, particle velocity, mass-based internal energy density, temperature, and mass-based entropy density) propagating

  1. Single point aerosol sampling: Evaluation of mixing and probe performance in a nuclear stack

    SciTech Connect (OSTI)

    Rodgers, J.C.; Fairchild, C.I.; Wood, G.O.; Ortiz, C.A.; Muyshondt, A.

    1996-01-01

    Alternative reference methodologies have been developed for sampling of radionuclides from stacks and ducts, which differ from the methods previously required by the United States Environmental Protection Agency. These alternative reference methodologies have recently been approved by the U.S. EPA for use in lieu of the current standard techniques. The standard EPA methods are prescriptive in selection of sampling locations and in design of sampling probes whereas the alternative reference methodologies are performance driven. Tests were conducted in a stack at Los Alamos National Laboratory to demonstrate the efficacy of some aspects of the alternative reference methodologies. Coefficients of variation of velocity, tracer gas, and aerosol particle profiles were determined at three sampling locations. Results showed that numerical criteria placed upon the coefficients of variation by the alternative reference methodologies were met at sampling stations located 9 and 14 stack diameters from the flow entrance, but not at a location that was 1.5 diameters downstream from the inlet. Experiments were conducted to characterize the transmission of 10 {mu}m aerodynamic diameter liquid aerosol particles through three types of sampling probes. The transmission ratio (ratio of aerosol concentration at the probe exit plane to the concentration in the free stream) was 107% for a 113 L min{sup {minus}1} (4-cfm) anistokinetic shrouded probe, but only 20% for an isokinetic probe that follows the existing EPA standard requirements. A specially designed isokinetic probe showed a transmission ratio of 63%. The shrouded probe performance would conform to the alternative reference methodologies criteria; however, the isokinetic probes would not. 13 refs., 9 figs., 1 tab.

  2. PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN

    E-Print Network [OSTI]

    PERFORMANCE EFFECTS OF AIR VELOCITY PROFILES IN A RESIDENTIAL HEAT PUMP By NATHAN ANDREW WEBER PROFILES IN A RESIDENTIAL HEAT PUMP Thesis Approved: _______________________________________ Thesis Advisor the air speed transducer mount and the Plexiglas model of the heat pump. Ipseng Iu and myself worked side

  3. Apparatus and method for laser velocity interferometry

    DOE Patents [OSTI]

    Stanton, Philip L. (Bernalillo County, NM); Sweatt, William C. (Albuquerque, NM); Crump, Jr., O. B. (Albuquerque, NM); Bonzon, Lloyd L. (Albuquerque, NM)

    1993-09-14

    An apparatus and method for laser velocity interferometry employing a fixed interferometer cavity and delay element. The invention permits rapid construction of interferometers that may be operated by those non-skilled in the art, that have high image quality with no drift or loss of contrast, and that have long-term stability even without shock isolation of the cavity.

  4. Gravitational Waves in G4v

    E-Print Network [OSTI]

    Carver Mead

    2015-03-16

    Gravitational coupling of the propagation four-vectors of matter wave functions is formulated in flat space-time. Coupling at the momentum level rather than at the "force-law" level greatly simplifies many calculations. This locally Lorentz-invariant approach (G4v) treats electromagnetic and gravitational coupling on an equal footing. Classical mechanics emerges from the incoherent aggregation of matter wave functions. The theory reproduces, to first order beyond Newton, the standard GR results for Gravity-Probe B, deflection of light by massive bodies, precession of orbits, gravitational red shift, and total gravitational-wave energy radiated by a circular binary system. Its predictions of total radiated energy from highly eccentric Kepler systems are slightly larger than those of similar GR treatments. G4v predictions differ markedly from those of GR for the gravitational-wave radiation patterns from rotating massive systems, and for the LIGO antenna pattern. The predicted antenna patterns have been shown to be highly distinguishable in the case of continuous gravitational-wave sources, and should therefore be testable as data from Advanced LIGO becomes available over the next few years.

  5. 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

  6. Local computation of angular velocity in rotational visual motion

    E-Print Network [OSTI]

    Grzywacz, Norberto

    Local computation of angular velocity in rotational visual motion Jose´ F. Barraza and Norberto M discrimination of angular velocity is local. Local discrimination of angular velocity requires an accurate of rotation result in a predictable systematic error when one is estimating local angular velocity. Our

  7. Global well-posedness of the 3-D full water wave problem

    E-Print Network [OSTI]

    Sijue Wu

    2009-10-13

    We consider the problem of global in time existence and uniqueness of solutions of the 3-D infinite depth full water wave problem. We show that the nature of the nonlinearity of the water wave equation is essentially of cubic and higher orders. For any initial interface that is sufficiently small in its steepness and velocity, we show that there exists a unique smooth solution of the full water wave problem for all time, and the solution decays at the rate $1/t$.

  8. Surface electromagnetic wave equations in a warm magnetized quantum plasma

    SciTech Connect (OSTI)

    Li, Chunhua; Yang, Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu, Zhengwei, E-mail: wuzw@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Center of Low Temperature Plasma Application, Yunnan Aerospace Industry Company, Kunming, 650229 Yunnan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

    2014-07-15

    Based on the single-fluid plasma model, a theoretical investigation of surface electromagnetic waves in a warm quantum magnetized inhomogeneous plasma is presented. The surface electromagnetic waves are assumed to propagate on the plane between a vacuum and a warm quantum magnetized plasma. The quantum magnetohydrodynamic model includes quantum diffraction effect (Bohm potential), and quantum statistical pressure is used to derive the new dispersion relation of surface electromagnetic waves. And the general dispersion relation is analyzed in some special cases of interest. It is shown that surface plasma oscillations can be propagated due to quantum effects, and the propagation velocity is enhanced. Furthermore, the external magnetic field has a significant effect on surface wave's dispersion equation. Our work should be of a useful tool for investigating the physical characteristic of surface waves and physical properties of the bounded quantum plasmas.

  9. Decay of helical Kelvin waves on a quantum vortex filament

    SciTech Connect (OSTI)

    Van Gorder, Robert A.

    2014-07-15

    We study the dynamics of helical Kelvin waves moving along a quantum vortex filament driven by a normal fluid flow. We employ the vector form of the quantum local induction approximation (LIA) due to Schwarz. For an isolated filament, this is an adequate approximation to the full Hall-Vinen-Bekarevich-Khalatnikov dynamics. The motion of such Kelvin waves is both translational (along the quantum vortex filament) and rotational (in the plane orthogonal to the reference axis). We first present an exact closed form solution for the motion of these Kelvin waves in the case of a constant amplitude helix. Such solutions exist for a critical wave number and correspond exactly to the Donnelly-Glaberson instability, so perturbations of such solutions either decay to line filaments or blow-up. This leads us to consider helical Kelvin waves which decay to line filaments. Unlike in the case of constant amplitude helical solutions, the dynamics are much more complicated for the decaying helical waves, owing to the fact that the rate of decay of the helical perturbations along the vortex filament is not constant in time. We give an analytical and numerical description of the motion of decaying helical Kelvin waves, from which we are able to ascertain the influence of the physical parameters on the decay, translational motion along the filament, and rotational motion, of these waves (all of which depend nonlinearly on time). One interesting finding is that the helical Kelvin waves do not decay uniformly. Rather, such waves decay slowly for small time scales, and more rapidly for large time scales. The rotational and translational velocity of the Kelvin waves depend strongly on this rate of decay, and we find that the speed of propagation of a helical Kelvin wave along a quantum filament is large for small time while the wave asymptotically slows as it decays. The rotational velocity of such Kelvin waves along the filament will increase over time, asymptotically reaching a finite value. These decaying Kelvin waves correspond to wave number below the critical value for the Donnelly-Glaberson instability, and hence our results on the Schwarz quantum LIA correspond exactly to what one would expect from prior work on the Donnelly-Glaberson instability.

  10. Observation of negative-frequency waves in a water tank: A classical analogue to the Hawking effect?

    E-Print Network [OSTI]

    Germain Rousseaux; Christian Mathis; Philippe Maissa; Thomas G. Philbin; Ulf Leonhardt

    2008-03-01

    The conversion of positive-frequency waves into negative-frequency waves at the event horizon is the mechanism at the heart of the Hawking radiation of black holes. In black-hole analogues, horizons are formed for waves propagating in a medium against the current when and where the flow exceeds the wave velocity. We report on the first direct observation of negative-frequency waves converted from positive-frequency waves in a moving medium. The measured degree of mode conversion is significantly higher than expected from theory.

  11. Linear Regression of Eye Velocity on Eye Position and Head Velocity Suggests a Common Oculomotor Neural Integrator

    E-Print Network [OSTI]

    Tank, David

    . The linear regression method presented here is valid for both fixation and low head velocity VOR dataLinear Regression of Eye Velocity on Eye Position and Head Velocity Suggests a Common Oculomotor Aksay, David W. Tank, and H. S. Seung. Linear regression of eye velocity on eye position and head

  12. Coiled tubing velocity strings keep wells unloaded

    SciTech Connect (OSTI)

    Wesson, H.R.; Shursen, J.L.

    1989-07-01

    Liquid loading is a problem in many older and even some newer gas wells, particularly in pressure depletion type reservoirs. This liquid loading results in decreased production and may even kill the well. The use of coiled tubing as a velocity string (or siphon string) has proved to be an economically viable alternative to allow continued and thus, increased cumulative production for wells experiencing liquid loading problems. Coiled tubing run inside the existing production string reduces the flow area, whether the well is produced up the tubing or up the annulus. This reduction in flow area results in an increase in flow velocity and thus, an increase in the well's ability to unload fluids.

  13. Relativistic Quaternionic Wave Equation II

    E-Print Network [OSTI]

    Schwartz, Charles

    2007-01-01

    Relativistic quaternionic wave equation. II J. Math. Phys.Relativistic quaternionic wave equation. II Charles Schwartzcomponent quaternionic wave equation recently introduced. A

  14. P- and S-body wave tomography of the state of Nevada.

    SciTech Connect (OSTI)

    Preston, Leiph

    2010-04-01

    P- and S-body wave travel times collected from stations in and near the state of Nevada were inverted for P-wave velocity and the Vp/Vs ratio. These waves consist of Pn, Pg, Sn and Sg, but only the first arriving P and S waves were used in the inversion. Travel times were picked by University of Nevada Reno colleagues and were culled for inclusion in the tomographic inversion. The resulting tomographic model covers the entire state of Nevada to a depth of {approx}90 km; however, only the upper 40 km indicate relatively good resolution. Several features of interest are imaged including the Sierra Nevada, basin structures, and low velocities at depth below Yucca Mountain. These velocity structure images provide valuable information to aide in the interpretation of geothermal resource areas throughout the state on Nevada.

  15. Entangled quantum probes for dynamical environmental noise

    E-Print Network [OSTI]

    Matteo A. C. Rossi; Matteo G. A. Paris

    2015-03-11

    We address the use of entangled qubits as quantum probes to characterize the dynamical noise induced by complex environments. In particular, we show that entangled probes improve estimation of the correlation time for a broad class of environmental noises compared to any sequential strategy involving single qubit preparation. The effect is present when the noise is faster than a threshold value, a regime which may always be achieved by tuning the coupling between the quantum probe and the environment inducing the noise. Our scheme exploits time-dependent sensitivity of quantum systems to decoherence and does not require dynamical control on the probes. We derive the optimal interaction time and the optimal probe preparation, showing that it corresponds to multiqubit GHZ states when entanglement is useful. We also show robustness of the scheme against depolarization or dephasing of the probe, and discuss simple measurements approaching optimal precision.

  16. Wave-induced chaos in a continuously fed unstirred reactor John H. Merkin,"Valery Petrov,bStephen K. Scottc*and Kenneth Showalterb

    E-Print Network [OSTI]

    Showalter, Kenneth

    Wave-induced chaos in a continuously fed unstirred reactor John H. Merkin,"Valery Petrov,bStephen K of a constant-velocity constant-form reaction wave that traverses the reaction domain, leaving behind, allowing further wave events to be initiated, which then propagate into the `recovered' region. The chaotic

  17. Effect of Resolution on Propagating Detonation Wave

    SciTech Connect (OSTI)

    Menikoff, Ralph

    2014-07-10

    Simulations of the cylinder test are used to illustrate the effect of mesh resolution on a propagating detonation wave. For this study we use the xRage code with the SURF burn model for PBX 9501. The adaptive mesh capability of xRage is used to vary the resolution of the reaction zone. We focus on two key properties: the detonation speed and the cylinder wall velocity. The latter is related to the release isentrope behind the detonation wave. As the reaction zone is refined (2 to 15 cells for cell size of 62 to 8?m), both the detonation speed and final wall velocity change by a small amount; less than 1 per cent. The detonation speed decreases with coarser resolution. Even when the reaction zone is grossly under-resolved (cell size twice the reaction-zone width of the burn model) the wall velocity is within a per cent and the detonation speed is low by only 2 per cent.

  18. Radial velocities of southern visual multiple stars

    SciTech Connect (OSTI)

    Tokovinin, Andrei; Pribulla, Theodor; Fischer, Debra E-mail: pribulla@ta3.sk

    2015-01-01

    High-resolution spectra of visual multiple stars were taken in 2008–2009 to detect or confirm spectroscopic subsystems and to determine their orbits. Radial velocities of 93 late-type stars belonging to visual multiple systems were measured by numerical cross-correlation. We provide the individual velocities, the width, and the amplitude of the Gaussians that approximate the correlations. The new information on the multiple systems resulting from these data is discussed. We discovered double-lined binaries in HD 41742B, HD 56593C, and HD 122613AB, confirmed several other known subsystems, and constrained the existence of subsystems in some visual binaries where both components turned out to have similar velocities. The orbits of double-lined subsystems with periods of 148 and 13 days are computed for HD 104471 Aa,Ab and HD 210349 Aa,Ab, respectively. We estimate individual magnitudes and masses of the components in these triple systems and update the outer orbit of HD 104471 AB.

  19. INNOVATIVE EDDY CURRENT PROBE FOR MICRO DEFECTS

    SciTech Connect (OSTI)

    Santos, Telmo G.; Vilaca, Pedro; Quintino, Luisa [IDMEC, Av. Rovisco Pais, 1049-001 Lisbon (Portugal); Santos, Jorge dos [GKSS, Max-Planck-Street 1, D-21502 Geesthacht (Germany); Rosado, Luis [IST, UTL, Av. Rovisco Pais, 1049-001 Lisbon (Portugal)

    2010-02-22

    This paper reports the development of an innovative eddy current (EC) probe, and its application to micro-defects on the root of the Friction Stir Welding (FSW). The new EC probe presents innovative concept issues, allowing 3D induced current in the material, and a lift-off independence. Validation experiments were performed on aluminium alloys processed by FSW. The results clearly show that the new EC probe is able to detect and sizing surface defects about 60 microns depth.

  20. Propagating and reflecting of spin wave in permalloy nanostrip with 360° domain wall

    SciTech Connect (OSTI)

    Zhang, Senfu; Mu, Congpu; Zhu, Qiyuan; Zheng, Qi; Liu, Xianyin; Wang, Jianbo; Liu, Qingfang

    2014-01-07

    By micromagnetic simulation, we investigated the interaction between propagating spin wave (or magnonic) and a 360° domain wall in a nanostrip. It is found that propagating spin wave can drive a 360° domain wall motion, and the velocity and direction are closely related to the transmission coefficient of the spin wave of the domain wall. When the spin wave passes through the domain wall completely, the 360° domain wall moves toward the spin wave source. When the spin wave is reflected by the domain wall, the 360° domain wall moves along the spin wave propagation direction. Moreover, when the frequency of the spin wave is coincident with that of the 360° domain wall normal mode, the 360° domain wall velocity will be resonantly enhanced no matter which direction the 360 DW moves along. On the other hand, when the spin wave is reflected from the moving 360° domain wall, we observed the Doppler effect clearly. After passing through a 360° domain wall, the phase of the spin wave is changed, and the phase shift is related to the frequency. Nevertheless, phase shift could be manipulated by the number of 360° domain walls that spin wave passing through.

  1. Horizon effects with surface waves on moving water

    E-Print Network [OSTI]

    Germain Rousseaux; Philippe Maissa; Christian Mathis; Pierre Coullet; Thomas G. Philbin; Ulf Leonhardt

    2010-10-01

    Surface waves on a stationary flow of water are considered, in a linear model that includes the surface tension of the fluid. The resulting gravity-capillary waves experience a rich array of horizon effects when propagating against the flow. In some cases three horizons (points where the group velocity of the wave reverses) exist for waves with a single laboratory frequency. Some of these effects are familiar in fluid mechanics under the name of wave blocking, but other aspects, in particular waves with negative co-moving frequency and the Hawking effect, were overlooked until surface waves were investigated as examples of analogue gravity [Sch\\"utzhold R and Unruh W G 2002 Phys. Rev. D 66 044019]. A comprehensive presentation of the various horizon effects for gravity-capillary waves is given, with emphasis on the deep water/short wavelength case kh>>1 where many analytical results can be derived. A similarity of the state space of the waves to that of a thermodynamic system is pointed out.

  2. AN EXTREME-ULTRAVIOLET WAVE ASSOCIATED WITH A SURGE

    SciTech Connect (OSTI)

    Zheng, Ruisheng; Jiang, Yunchun; Yang, Jiayan; Bi, Yi; Hong, Junchao; Yang, Bo; Yang, Dan

    2013-02-10

    Taking advantage of the high temporal and spatial resolution observations from the Solar Dynamics Observatory, we present an extreme-ultraviolet (EUV) wave associated with a surge on 2010 November 13. Due to the magnetic flux cancelation, some surges formed in the source active region (AR). The strongest surge produced our studied event. The surge was deflected by the nearby loops that connected to another AR, and disrupted the overlying loops that slowly expanded and eventually evolved into a weak coronal mass ejection (CME). The surge was likely associated with the core of the CME. The EUV wave happened after the surge deflected. The wave departed far from the flare center and showed a close location relative to the deflected surge. The wave propagated in a narrow angular extent, mainly in the ejection direction of the surge. The close timing and location relations between the EUV wave and the surge indicate that the wave was closely associated with the CME. The wave had a velocity of 310-350 km s{sup -1}, while the speeds of the surge and the expanding loops were about 130 and 150 km s{sup -1}, respectively. All of the results suggest that the EUV wave was a fast-mode wave and was most likely triggered by the weak CME.

  3. Penetration of lower hybrid current drive waves in tokamaks

    SciTech Connect (OSTI)

    Horton, W. [The University of Texas at Austin, Austin, Texas 78712 (United States) [The University of Texas at Austin, Austin, Texas 78712 (United States); Aix-Marseille University, 58, Bd Charles Livon, 13284 Marseille (France); Goniche, M.; Peysson, Y.; Decker, J.; Ekedahl, A.; Litaudon, X. [CEA, IRFM, F-13108 Saint-Paul-Lez Durance (France)] [CEA, IRFM, F-13108 Saint-Paul-Lez Durance (France)

    2013-11-15

    Lower hybrid (LH) ray propagation in toroidal plasma is shown to be controlled by combination of the azimuthal spectrum launched by the antenna, the poloidal variation of the magnetic field, and the scattering of the waves by the drift wave fluctuations. The width of the poloidal and radial radio frequency wave spectrum increases rapidly as the rays penetrate into higher density and scatter from the drift waves. The electron temperature gradient (ETG) spectrum is particularly effective in scattering the LH waves due to its comparable wavelengths and phase velocities. ETG turbulence is also driven by the radial gradient of the electron current profile giving rise to an anomalous viscosity spreading the LH driven plasma currents. The LH wave scattering is derived from a Fokker-Planck equation for the distribution of the ray trajectories with diffusivities derived from the drift wave fluctuations. The condition for chaotic diffusion for the rays is derived. The evolution of the poloidal and radial mode number spectrum of the lower hybrid waves are both on the antenna spectrum and the spectrum of the drift waves. Antennas launching higher poloidal mode number spectra drive off-axis current density profiles producing negative central shear [RS] plasmas with improved thermal confinement from ETG transport. Core plasma current drive requires antennas with low azimuthal mode spectra peaked at m = 0 azimuthal mode numbers.

  4. Probing Organic Transistors with Infrared Beams

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

    University of California and the ALS has succeeded in probing the intrinsic electronic properties of the charge carriers in organic FETs using infrared spectromicroscopy. The...

  5. A rational route to probing membrane proteins

    E-Print Network [OSTI]

    Keating, Amy E.

    A recent report describes the design of short peptides that bind specifically to transmembrane regions of integrins, providing an exciting tool for probing the biology of membrane proteins.

  6. PROBING DENSE NUCLEAR MATTER VIA NUCLEAR COLLISIONS

    E-Print Network [OSTI]

    Stocker, H.

    2012-01-01

    University of California. LBL-12095 Probing Dense NuclearMatter Nuclear Collisions* v~a H. Stocker, M.Gyulassy and J. Boguta Nuclear Science Division Lawrence

  7. Terahertz imaging of sub-wavelength particles with Zenneck surface waves

    SciTech Connect (OSTI)

    Navarro-Cía, M., E-mail: m.navarro@imperial.ac.uk [Optical and Semiconductor Devices Group, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2BT (United Kingdom); Centre for Plasmonics and Metamaterials, Imperial College London, London SW7 2AZ (United Kingdom); Centre for Terahertz Science and Engineering, Imperial College London, London SW7 2AZ (United Kingdom); Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Natrella, M.; Graham, C.; Renaud, C. C.; Seeds, A. J.; Mitrofanov, O., E-mail: o.mitrofanov@ucl.ac.uk [Department of Electronic and Electrical Engineering, University College London, Torrington Place, London WC1E 7JE (United Kingdom); Dominec, F.; Kužel, P., E-mail: kuzelp@fzu.cz [Institute of Physics, Academy of Sciences of the Czech Republic, Na Slovance 2, 182 21 Prague 8 (Czech Republic); Delagnes, J. C.; Mounaix, P., E-mail: p.mounaix@loma.u-bordeaux1.fr [LOMA, Bordeaux 1 University, CNRS UMR 4798, 351 cours de la Libération, 33405 Talence (France)

    2013-11-25

    Impact of sub-wavelength-size dielectric particles on Zenneck surface waves on planar metallic antennas is investigated at terahertz (THz) frequencies with THz near-field probe microscopy. Perturbations of the surface waves show the particle presence, despite its sub-wavelength size. The experimental configuration, which utilizes excitation of surface waves at metallic edges, is suitable for THz imaging of dielectric sub-wavelength size objects. As a proof of concept, the effects of a small strontium titanate rectangular particle and a titanium dioxide sphere on the surface field of a bow-tie antenna are experimentally detected and verified using full-wave simulations.

  8. Implementation of electromagnetically induced transparency in a metamaterial controlled with auxiliary waves

    E-Print Network [OSTI]

    Nakanishi, Toshihiro

    2015-01-01

    We propose a metamaterial to realize true electromagnetically induced transparency (EIT), where the incidence of an auxiliary electromagnetic wave called the control wave induces transparency for a probe wave. The analogy to the original EIT effect in an atomic medium is shown through analytical and numerical calculations derived from a circuit model for the metamaterial. We performed experiments to demonstrate the EIT effect of the metamaterial in the microwave region. The width and position of the transparent region can be controlled by the power and frequency of the control wave. We also observed asymmetric transmission spectra unique to the Fano resonance.

  9. The transverse and rotational motions of magnetohydrodynamic kink waves in the solar atmosphere

    SciTech Connect (OSTI)

    Goossens, M.; Van Doorsselaere, T. [Centre for Mathematical Plasma Astrophysics, Katholieke Universiteit Leuven, Celestijnenlaan 200B, bus 2400, B-3001 Herverlee (Belgium); Soler, R.; Terradas, J. [Departament de Física, Universitat de les Illes Balears, E-07122 Palma de Mallorca (Spain); Verth, G., E-mail: marcel.goossens@wis.kuleuven.be [Solar Physics and Space Plasma Research Centre (SP2RC), The University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom)

    2014-06-10

    Magnetohydrodynamic (MHD) kink waves have now been observed to be ubiquitous throughout the solar atmosphere. With modern instruments, they have now been detected in the chromosphere, interface region, and corona. The key purpose of this paper is to show that kink waves do not only involve purely transverse motions of solar magnetic flux tubes, but the velocity field is a spatially and temporally varying sum of both transverse and rotational motion. Taking this fact into account is particularly important for the accurate interpretation of varying Doppler velocity profiles across oscillating structures such as spicules. It has now been shown that, as well as bulk transverse motions, spicules have omnipresent rotational motions. Here we emphasize that caution should be used before interpreting the particular MHD wave mode/s responsible for these rotational motions. The rotational motions are not necessarily signatures of the classic axisymmetric torsional Alfvén wave alone, because kink motion itself can also contribute substantially to varying Doppler velocity profiles observed across these structures. In this paper, the displacement field of the kink wave is demonstrated to be a sum of its transverse and rotational components, both for a flux tube with a discontinuous density profile at its boundary, and one with a more realistic density continuum between the internal and external plasma. Furthermore, the Doppler velocity profile of the kink wave is forward modeled to demonstrate that, depending on the line of sight, it can either be quite distinct or very similar to that expected from a torsional Alfvén wave.

  10. 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, ...

  11. 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 ...

  12. Scale effects on velocity dispersion: From ray to effective medium theories in stratified media

    SciTech Connect (OSTI)

    Marion, D. (Elf Aquitaine, Pau (France)); Mukerji, T.; Mavko, G. (Stanford Univ., CA (United States). Rockphysics Lab.)

    1994-10-01

    Wave propagation in stratified media may be explained by ray theory, effective medium theory, or scattering theory depending on the scales of wavelength and layer spacing. To effectively integrate and use seismic data ate different frequencies and widely varying scales, it is essential to understand the domain of applicability of long and short wavelength behavior and the transition between them. A joint experimental and theoretical study was conducted to investigate velocity behavior at the transition from ray theory to effective medium theory in stratified media. Velocity measurements were performed at 50 and 500 kHz on periodic media composed of steel and plastic discs. The ratio of wavelength to layer spacing, [lambda]/d, spanned more than two orders of magnitude between 0.1 and 50, and the volume fraction of steel ranged from 9 to 89 percent by volume. The results confirm that velocities in stratified media depend on composition and are controlled by the ratio of wavelength to layer spacing. Velocities in the short wavelength limit are generally faster than velocities in the long wavelength limit. The authors find that transition from ray to effective medium approximations occurs over a narrow range of [lambda]/d at a value of approximately 10. The amount of velocity change increases with impedance contrast, but the value of [lambda]/d at the transition is generally independent of the composition of the stratified medium. The numerically simulated waveforms are in close agreement with the experimentally observed delayed first arrival in the long wavelength limit and with the reduced amplitudes at the transition from short to long wavelength regime.

  13. PROTOSTELLAR JETS ENCLOSED BY LOW-VELOCITY OUTFLOWS

    SciTech Connect (OSTI)

    Machida, Masahiro N.

    2014-11-20

    A protostellar jet and outflow are calculated for ?270 yr following the protostar formation using a three-dimensional magnetohydrodynamics simulation, in which both the protostar and its parent cloud are spatially resolved. A high-velocity (?100 km s{sup –1}) jet with good collimation is driven near the disk's inner edge, while a low-velocity (? 10 km s{sup –1}) outflow with a wide opening angle appears in the outer-disk region. The high-velocity jet propagates into the low-velocity outflow, forming a nested velocity structure in which a narrow high-velocity flow is enclosed by a wide low-velocity flow. The low-velocity outflow is in a nearly steady state, while the high-velocity jet appears intermittently. The time-variability of the jet is related to the episodic accretion from the disk onto the protostar, which is caused by gravitational instability and magnetic effects such as magnetic braking and magnetorotational instability. Although the high-velocity jet has a large kinetic energy, the mass and momentum of the jet are much smaller than those of the low-velocity outflow. A large fraction of the infalling gas is ejected by the low-velocity outflow. Thus, the low-velocity outflow actually has a more significant effect than the high-velocity jet in the very early phase of the star formation.

  14. Gravitational Waves on Conductors

    E-Print Network [OSTI]

    A. Lewis Licht

    2004-03-12

    We consider a gravitational wave of arbitrary frequency incident on a normal or a super-conductor. The gravitationally induced fields inside the conductor are derived. The outward propagating EM waves are calculated for a low frequency wave on a small sphere and for a high frequency wave incident on a large disk. We estimate for both targets the GW to EM conversion efficiencies and also the magnitude of the superconductor's phase perturbation.

  15. Crustal structure of the Gamburtsev Mountains, East Antarctica, from S-wave receiver functions and Rayleigh wave phase velocities

    E-Print Network [OSTI]

    , USA c Dept. of Earth and Planetary Sciences, Washington University in St. Louis, St. Louis, MO 63130 tectonic features on Earth. Buried beneath several kilometers of ice, the mountains are characterized large-scale ice sheets that formed in Antarctica as the Earth's climate cooled ~34 Ma (Bo et al., 2009

  16. Bragg grating rogue wave

    E-Print Network [OSTI]

    Degasperis, Antonio; Aceves, Alejandro B

    2015-01-01

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

  17. Wave Particles Cem Yuksel

    E-Print Network [OSTI]

    Keyser, John

    Wave Particles Cem Yuksel Computer Science Texas A&M University Donald H. House Visualization captured from our real-time simulation system (approximately 100,000 wave particles) Abstract We present a new method for the real-time simulation of fluid sur- face waves and their interactions with floating

  18. 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

  19. Near-field examination of perovskite-based superlenses and superlens-enhanced probe-object coupling

    E-Print Network [OSTI]

    Kehr, Susanne C; Martin, L W; Yu, P; Gajek, M; Yang, S -Y; Yang, C -H; Wenzel, M T; Jacob, R; von Ribbeck, H -G; Helm, M; Zhang, X; Eng, L M; Ramesh, R; 10.1038/ncomms1249

    2011-01-01

    A planar slab of negative index material works as a superlens with sub-diffraction-limited imaging resolution, since propagating waves are focused and, moreover, evanescent waves are reconstructed in the image plane. Here, we demonstrate a superlens for electric evanescent fields with low losses using perovskites in the mid-infrared regime. The combination of near-field microscopy with a tunable free-electron laser allows us to address precisely the polariton modes, which are critical for super-resolution imaging. We spectrally study the lateral and vertical distributions of evanescent waves around the image plane of such a lens, and achieve imaging resolution of wavelength/14 at the superlensing wavelength. Interestingly, at certain distances between the probe and sample surface, we observe a maximum of these evanescent fields. Comparisons with numerical simulations indicate that this maximum originates from an enhanced coupling between probe and object, which might be applicable for multifunctional circuits...

  20. 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

  1. On the local properties of highly nonlinear unsteady gravity water waves. Part 1. Slowdown, kinematics and energetics

    E-Print Network [OSTI]

    Barthelemy, X; Peirson, W L; Dias, F; Allis, M

    2015-01-01

    The kinematic properties of unsteady highly non-linear 3D wave groups have been investigated using a numerical wave tank. Although carrier wave speeds based on zero-crossing analysis remain within +-7% of linear theory predictions, crests and troughs locally undertake a systematic cyclical leaning from forward to backward as the crests/troughs transition through their maximum amplitude. Consequently, both crests and troughs slow down by approximately 15% of the linear velocity, in sharp contrast to the predictions of finite amplitude Stokes steady wavetrain theory. Velocity profiles under the crest maximum have been investigated and surface values in excess of 1.8 times the equivalent Stokes velocity can be observed. Equipartitioning between depth-integrated kinetic and potential energy holds globally on the scale of the wave group. However, equipartitioning does not occur at crests and troughs (even for low amplitude Stokes waves), where the local ratio of potential to total energy varies systemically as a f...

  2. Probing Efficient Cosmic-Ray Acceleration in Young Supernovae

    E-Print Network [OSTI]

    Dwarkadas, Vikram V; Marcowith, A; Tatischeff, V

    2015-01-01

    The formation of a core collapse supernovae (SNe) results in a fast (but non- or mildly-relativistic) shock wave expanding outwards into the surrounding medium. The medium itself is likely modified due to the stellar mass-loss from the massive star progenitor, which may be Wolf-Rayet stars (for Type Ib/c SNe), red supergiant stars (for type IIP and perhaps IIb and IIL SNe), or some other stellar type. The wind mass-loss parameters determine the density structure of the surrounding medium. Combined with the velocity of the SN shock wave, this regulates the shock acceleration process. In this article we discuss the essential parameters that control the particle acceleration and gamma-ray emission in SNe, with particular reference to the Type IIb SN 1993J. The shock wave expanding into the high density medium leads to fast particle acceleration, giving rise to rapidly-growing plasma instabilities driven by the acceleration process itself. The instabilities grow over intraday timescales. This growth, combined wit...

  3. Angular velocity of gravitational radiation from precessing binaries and the corotating frame

    E-Print Network [OSTI]

    Michael Boyle

    2013-04-10

    This paper defines an angular velocity for time-dependent functions on the sphere, and applies it to gravitational waveforms from compact binaries. Because it is geometrically meaningful and has a clear physical motivation, the angular velocity is uniquely useful in helping to solve an important---and largely ignored---problem in models of compact binaries: the inverse problem of deducing the physical parameters of a system from the gravitational waves alone. It is also used to define the corotating frame of the waveform. When decomposed in this frame, the waveform has no rotational dynamics and is therefore as slowly evolving as possible. The resulting simplifications lead to straightforward methods for accurately comparing waveforms and constructing hybrids. As formulated in this paper, the methods can be applied robustly to both precessing and nonprecessing waveforms, providing a clear, comprehensive, and consistent framework for waveform analysis. Explicit implementations of all these methods are provided in accompanying computer code.

  4. Direct Optical Probing of Transverse Electric Mode in Graphene

    E-Print Network [OSTI]

    Menabde, Sergey; Kornev, Evgeny; Lee, Changhee; Park, Namkyoo

    2015-01-01

    Unique electrodynamic response of graphene implies a manifestation of an unusual propagating and localised transverse-electric (TE) mode near the spectral onset of interband transitions. However, excitation and further detection of the TE mode supported by graphene is considered to be a challenge for it is extremely sensitive to excitation environment and phase matching condition adherence. Here for the first time, we experimentally prove an existence of the TE mode by its direct optical probing, demonstrating significant coupling to an incident wave in electrically doped multilayer graphene sheet at room temperature. We believe that proposed technique of careful phase matching and obtained access to graphene TE excitation would stimulate further studies of this unique phenomenon, and enable its potential employing in various fields of photonics as well as for characterization of graphene.

  5. Probing the Sun with ALMA: observations and simulations

    E-Print Network [OSTI]

    Loukitcheva, Maria; White, Stephen M; Carlsson, Mats

    2015-01-01

    ALMA will open a new chapter in the study of the Sun by providing a leap in spatial resolution and sensitivity compared to currently available mm wave- length observations. In preparation of ALMA, we have carried out a large number of observational tests and state-of-the-art radiation MHD simulations. Here we review the best available observations of the Sun at millimeter wavelengths.Using state of the art radiation MHD simulations of the solar atmosphere we demonstrate the huge potential of ALMA observations for uncovering the nature of the solar chromosphere. We show that ALMA will not only provide a reliable probe of the thermal structure and dynamics of the chromosphere, it will also open up a powerful new diagnostic of magnetic field at chromospheric heights, a fundamentally important, but so far poorly known parameter.

  6. Scanning probe microscopy competency development

    SciTech Connect (OSTI)

    Hawley, M.E.; Reagor, D.W.; Jia, Quan Xi

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at Los Alamos National Laboratory (LANL). The project collaborators developed an ultra-high vacuum scanning tunneling microscope (UHV-STM) capability, integrated it with existing scanning probe microscopes, and developed new, advanced air-based scanning force techniques (SPMs). Programmatic, basic, and industrially related laboratory research requires the existence of SPMs, as well as expertise capable of providing local nano-scale information. The UHV-STM capability, equipped with load-lock system and several surface science techniques, will allow introduction, examination, and reaction of surfaces prepared under well-controlled vacuum conditions, including the examination of morphology and local bonding associated with the initial stages of film growth under controlled growth conditions. The resulting capabilities will enable the authors to respond to a variety of problems requiring local characterization of conducting and nonconducting surfaces in liquids, air, and UHV.

  7. MERIT Pump/Probe Data OutlineOutline

    E-Print Network [OSTI]

    McDonald, Kirk

    MERIT Pump/Probe Data Analysis OutlineOutline The pump/probe program Particle detector response correction Pump/probe analysis results NFMCC Collaboration Meeting , LBNL, January 26, 2009 Ilias Efthymiopoulos - CERN #12;The pump/probe program #12;The pump/probe program Use of the CERN PS flexibility

  8. An instrument to measure extended particle size and velocity ranges in multiphase flows

    SciTech Connect (OSTI)

    Wood, C.P.; Hess, C.F.

    1995-12-31

    This paper describes a miniaturized particle sizing velocimeter developed and built by MetroLaser to measure the spatial and temporal distributions of particle size and velocity. The instrument is the first of its kind to utilize the pulse displacement technique (PDT) to measure particle size. PDT is based on the detection of scattered refraction and reflection pulses which sweep past a detector at different times as a particle traverses a narrow laser sheet. In conjunction with Mie scattering and a time-of-fight velocity measuring technique, the instrument provides detailed distributions of particle size from 2 {micro}m to 6,000 {micro}m in two optical configurations, and particle velocity from 0.5 m/s to 150 m/s. This paper summarizes the theoretical foundation of PDT which allows the calculation of particle diameter from various optical parameters such as refractive index and collection angle. An overview of the instrument is presented, followed by a brief description of the miniaturized optical probe. The processing of data is described and, lastly, the results of experimental studies are presented which verify the accuracy and versatility of the instrument.

  9. Low velocity limits of cold atom clocks

    E-Print Network [OSTI]

    J. Muñoz; I. Lizuain; J. G. Muga

    2009-09-08

    Fundamental low-energy limits to the accuracy of quantum clock and stopwatch models in which the clock hand motion is activated by the presence of a particle in a region of space have been studied in the past, but their relevance for actual atomic clocks had not been assessed. In this work we address the effect of slow atomic quantum motion on Rabi and Ramsey resonance fringe patterns, as a perturbation of the results based on classical atomic motion. We find the dependence of the fractional error of the corresponding atomic clocks on the atomic velocity and interaction parameters.

  10. New pure shear acoustic surface waves guided by cuts in magneto-electro-elastic materials

    E-Print Network [OSTI]

    Arman Melkumyan

    2006-07-12

    It is shown that new pure shear acoustic surface waves with five different velocities can be guided by stress free plane cuts with different magneto-electrical properties in magneto-electro-elastic materials. The possibility for the surface waves to be guided by a cut in pairs, which is reported in this paper, is new in magneto-electro-elastic materials and has no counterpart in piezoelectric materials. The five velocities of propagation of the surface waves are obtained in explicit forms. It is shown that the possibility for the surface waves to be guided in pairs disappears and the number of surface waves decreases from 5 to 1 if the magneto-electro-elastic material is changed to a piezoelectric material.

  11. Simple Scalings for Various Regimes of Electron Acceleration in Surface Plasma Waves

    E-Print Network [OSTI]

    Riconda, C; Vialis, T; Grech, M

    2015-01-01

    Different electron acceleration regimes in the evanescent field of a surface plasma wave are studied by considering the interaction of a test electron with the high-frequency electromagnetic field of a surface wave. The non-relativistic and relativistic limits are investigated. Simple scalings are found demonstrating the possibility to achieve an efficient conversion of the surface wave field energy into electron kinetic energy. This mechanism of electron acceleration can provide a high-frequency pulsed source of relativistic electrons with a well defined energy. In the relativistic limit, the most energetic electrons are obtained in the so-called electromagnetic regime for surface waves. In this regime the particles are accelerated to velocities larger than the wave phase velocity, mainly in the direction parallel to the plasma-vacuum interface.

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

    E-Print Network [OSTI]

    Qian, Tingting

    2010-07-14

    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...

  13. Tube curvature measuring probe and method

    DOE Patents [OSTI]

    Sokol, George J. (Scotia, NY)

    1990-01-01

    The present invention is directed to a probe and method for measuring the radius of curvature of a bend in a section of tubing. The probe includes a member with a pair of guide means, one located at each end of the member. A strain gauge is operatively connected to the member for detecting bending stress exrted on the member as the probe is drawn through and in engagement with the inner surface of a section of tubing having a bend. The method of the present invention includes steps utilizing a probe, like the aforementioned probe, which can be made to detect bends only in a single plane when having a fixed orientation relative the section of tubing to determine the maximum radius of curvature of the bend.

  14. Using the Tremaine-Weinberg method to measure pattern speeds from H?velocity maps

    E-Print Network [OSTI]

    John Beckman; Kambiz Fathi; Nuria Piñol; Olivier Hernandez; Claude Carignan; Isabel Pérez

    2008-10-29

    The Tremaine-Weinberg method is a well-known model independent technique for measuring density wave pattern speeds in spiral galaxies. Here we show how it can be applied to the data cubes (maps of surface brightness and velocity) obtained in H-alpha emission using a Fabry-Perot spectrometer. One of the main difficulties, the discontinuity of the H-alpha emission, is resolved using the neighbouring stellar continuum delivered by the data cube. We argue from symmetry that the motions not associated with the density wave should cancel. We show that our pattern speeds are reasonable by computing corotation radii, and comparing them to measured bar lengths. Simulations including star forming gas also add credibility to our results. Nevertheless it will be necessary to compare them with results using the spectra of the stellar components to quantify any systematic deviations from valid pattern speed values.

  15. Using the Tremaine-Weinberg method to measure pattern speeds from H\\alpha velocity maps

    E-Print Network [OSTI]

    Beckman, John; Piñol, Nuria; Hernandez, Olivier; Carignan, Claude; Pérez, Isabel

    2008-01-01

    The Tremaine-Weinberg method is a well-known model independent technique for measuring density wave pattern speeds in spiral galaxies. Here we show how it can be applied to the data cubes (maps of surface brightness and velocity) obtained in H-alpha emission using a Fabry-Perot spectrometer. One of the main difficulties, the discontinuity of the H-alpha emission, is resolved using the neighbouring stellar continuum delivered by the data cube. We argue from symmetry that the motions not associated with the density wave should cancel. We show that our pattern speeds are reasonable by computing corotation radii, and comparing them to measured bar lengths. Simulations including star forming gas also add credibility to our results. Nevertheless it will be necessary to compare them with results using the spectra of the stellar components to quantify any systematic deviations from valid pattern speed values.

  16. Velocity-selected molecular pulses produced by an electric guide

    SciTech Connect (OSTI)

    Sommer, C.; Motsch, M.; Chervenkov, S.; Buuren, L. D. van; Zeppenfeld, M.; Pinkse, P. W. H.; Rempe, G. [Max-Planck-Institut fuer Quantenoptik, Hans-Kopfermann-Str. 1, D-85748 Garching (Germany)

    2010-07-15

    Electrostatic velocity filtering is a technique for the production of continuous guided beams of slow polar molecules from a thermal gas. We extended this technique to produce pulses of slow molecules with a narrow velocity distribution around a tunable velocity. The pulses are generated by sequentially switching the voltages on adjacent segments of an electric quadrupole guide synchronously with the molecules propagating at the desired velocity. This technique is demonstrated for deuterated ammonia (ND{sub 3}), delivering pulses with a velocity in the range of 20-100 m/s and a relative velocity spread of (16{+-}2)% at full width at half maximum. At velocities around 60 m/s, the pulses contain up to 10{sup 6} molecules each. The data are well reproduced by Monte Carlo simulations, which provide useful insight into the mechanisms of velocity selection.

  17. Radial Velocity Variability of Field Brown Dwarfs

    E-Print Network [OSTI]

    Prato, L; Rice, E L; McLean, I S; Kirkpatrick, J D; Burgasser, A J; Kim, S S

    2015-01-01

    We present paper six of the NIRSPEC Brown Dwarf Spectroscopic Survey, an analysis of multi-epoch, high-resolution (R~20,000) spectra of 25 field dwarf systems (3 late-type M dwarfs, 16 L dwarfs, and 6 T dwarfs) taken with the NIRSPEC infrared spectrograph at the W. M. Keck Observatory. With a radial velocity precision of ~2 km/s, we are sensitive to brown dwarf companions in orbits with periods of a few years or less given a mass ratio of 0.5 or greater. We do not detect any spectroscopic binary brown dwarfs in the sample. Given our target properties, and the frequency and cadence of observations, we use a Monte Carlo simulation to determine the detection probability of our sample. Even with a null detection result, our 1 sigma upper limit for very low mass binary frequency is 18%. Our targets included 7 known, wide brown dwarf binary systems. No significant radial velocity variability was measured in our multi-epoch observations of these systems, even for those pairs for which our data spanned a significant ...

  18. The Systemic Velocity of Eta Carinae

    E-Print Network [OSTI]

    Nathan Smith

    2004-06-23

    High-resolution spectra of molecular hydrogen in the Homunculus nebula allow for the first direct measurement of the systemic velocity of Eta Carinae. Near-infrared long-slit data for H2 1-0 S(1) lambda 21218 obtained with the Phoenix spectrometer on the Gemini South telescope give Vsys=-8.1pm1 km/s (heliocentric), or VLSR=-19.7pm1 km/s, from the average of the near and far sides of the Homunculus. This measurement considerably improves the precision for the value of -7pm10 km/s inferred from neighboring O-type stars in the Carina nebula. New near-infrared spectra also provide a high-resolution line profile of [Fe II] lambda 16435 emission from gas condensations known as the Weigelt objects without contamination from the central star, revealing a line shape with complex kinematic structure. Previously, uncertainty in the Weigelt knots' kinematics was dominated by the adopted systemic velocity of Eta Car.

  19. Four-probe measurements with a three-probe scanning tunneling microscope

    SciTech Connect (OSTI)

    Salomons, Mark [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada)] [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada); Martins, Bruno V. C.; Zikovsky, Janik; Wolkow, Robert A., E-mail: rwolkow@ualberta.ca [National Institute for Nanotechnology, National Research Council of Canada, Edmonton, Alberta T6G 2M9 (Canada); Department of Physics, University of Alberta, Edmonton, Alberta T6G 2E1 (Canada)

    2014-04-15

    We present an ultrahigh vacuum (UHV) three-probe scanning tunneling microscope in which each probe is capable of atomic resolution. A UHV JEOL scanning electron microscope aids in the placement of the probes on the sample. The machine also has a field ion microscope to clean, atomically image, and shape the probe tips. The machine uses bare conductive samples and tips with a homebuilt set of pliers for heating and loading. Automated feedback controlled tip-surface contacts allow for electrical stability and reproducibility while also greatly reducing tip and surface damage due to contact formation. The ability to register inter-tip position by imaging of a single surface feature by multiple tips is demonstrated. Four-probe material characterization is achieved by deploying two tips as fixed current probes and the third tip as a movable voltage probe.

  20. Modeling coiled tubing velocity strings for gas wells

    SciTech Connect (OSTI)

    Martinez, J.; Martinez, A.

    1995-12-31

    Multiphase flowing pressure and velocity prediction models are necessary to coiled tubing velocity string design. A model used by most of the coiled tubing service companies or manufacturers is reviewed. Guidance is provided for selecting a coiled tubing of the proper size. The steps include: (1) Measured data matching; (2) Fluid property adjustment; (3) Pressure, velocity, and holdup selection; (4) Correlation choice; (5) Coiled tubing selection. A velocity range for the lift of liquid is given.

  1. Low velocity blunt impacts on composite aircraft structures

    E-Print Network [OSTI]

    Whisler, Daniel A.

    2009-01-01

    as predict the velocity and energy right before the impacthit right at failure confirms the failure energy. To be

  2. Seismic Technology Adapted to Analyzing and Developing Geothermal Systems Below Surface-Exposed High-Velocity Rocks Final Report

    SciTech Connect (OSTI)

    Hardage, Bob A; DeAngelo, Michael V; Ermolaeva, Elena; Hardage, Bob A; Remington, Randy; Sava, Diana; Wagner, Donald; Wei, Shuijion

    2013-02-28

    The objective of our research was to develop and demonstrate seismic data-acquisition and data-processing technologies that allow geothermal prospects below high-velocity rock outcrops to be evaluated. To do this, we acquired a 3-component seismic test line across an area of exposed high-velocity rocks in Brewster County, Texas, where there is high heat flow and surface conditions mimic those found at numerous geothermal prospects. Seismic contractors have not succeeded in creating good-quality seismic data in this area for companies who have acquired data for oil and gas exploitation purposes. Our test profile traversed an area where high-velocity rocks and low-velocity sediment were exposed on the surface in alternating patterns that repeated along the test line. We verified that these surface conditions cause non-ending reverberations of Love waves, Rayleigh waves, and shallow critical refractions to travel across the earth surface between the boundaries of the fast-velocity and slow-velocity material exposed on the surface. These reverberating surface waves form the high level of noise in this area that does not allow reflections from deep interfaces to be seen and utilized. Our data-acquisition method of deploying a box array of closely spaced geophones allowed us to recognize and evaluate these surface-wave noise modes regardless of the azimuth direction to the surface anomaly that backscattered the waves and caused them to return to the test-line profile. With this knowledge of the surface-wave noise, we were able to process these test-line data to create P-P and SH-SH images that were superior to those produced by a skilled seismic data-processing contractor. Compared to the P-P data acquired along the test line, the SH-SH data provided a better detection of faults and could be used to trace these faults upward to the boundaries of exposed surface rocks. We expanded our comparison of the relative value of S-wave and P-wave seismic data for geothermal applications by inserting into this report a small part of the interpretation we have done with 3C3D data across Wister geothermal field in the Imperial Valley of California. This interpretation shows that P-SV data reveal faults (and by inference, also fractures) that cannot be easily, or confidently, seen with P-P data, and that the combination of P-P and P-SV data allows VP/VS velocity ratios to be estimated across a targeted reservoir interval to show where an interval has more sandstone (the preferred reservoir facies). The conclusion reached from this investigation is that S-wave seismic technology can be invaluable to geothermal operators. Thus we developed a strong interest in understanding the direct-S modes produced by vertical-force sources, particularly vertical vibrators, because if it can be demonstrated that direct-S modes produced by vertical-force sources can be used as effectively as the direct-S modes produced by horizontal-force sources, geothermal operators can acquire direct-S data across many more prospect areas than can be done with horizontal-force sources, which presently are limited to horizontal vibrators. We include some of our preliminary work in evaluating direct-S modes produced by vertical-force sources.

  3. A Langmuir Probe Diagnostic for Use in Inhomogeneous, Time-Varying Plasmas Produced by High-Energy Laser Ablation

    SciTech Connect (OSTI)

    Patterson, J R; Emig, J A; Fournier, K B; Jenkins, P P; Trautz, K M; Seiler, S W; Davis, J F

    2012-05-01

    Langmuir probes (LP) are used extensively to characterize plasma environments produced by radio frequency, pulsed plasma thrusters, and laser ablation. We discuss here the development of a LP diagnostic to examine high-density, high-temperature inhomogeneous plasmas such as those that can be created at the University of Rochester's Laboratory for Laser Energetics OMEGA facility. We have configured our diagnostic to examine the velocity of the plasma expanding from the target. We observe velocities of approximately 16-17 cm/{micro}s, with individual LP currents displaying complex structures, perhaps due to the multiple atomic species and ionization states that exist.

  4. Mother templates for gravitational wave chirps

    E-Print Network [OSTI]

    B. S. Sathyaprakash

    2000-10-11

    Templates used in a search for binary black holes and neutron stars in gravitational wave interferometer data will have to be computed on-line since the computational storage and retrieval costs for the template bank are too expensive. The conventional dimensionless variable $T=(c^3/Gm)t,$ where $m$ is the total mass of a binary, in the time-domain and a not-so-conventional velocity-like variable $v=(\\pi Gm f)^{1/3}$ in the Fourier-domain, render the phasing of the waves independent of the total mass of the system enabling the construction of {\\it mother templates} that depend only on the mass ratio of a black hole binary. Use of such mother templates in a template bank will bring about a reduction in computational costs up to a factor of 10 and a saving on storage by a factor of 100.

  5. Characteristics of transverse waves in chromospheric mottles

    SciTech Connect (OSTI)

    Kuridze, D.; Mathioudakis, M.; Jess, D. B.; Keenan, F. P. [Astrophysics Research Center, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN (United Kingdom); Verth, G.; Erdélyi, R. [Solar Physics and Space Plasma Research Center (SP2RC), University of Sheffield, Hicks Building, Hounsfield Road, Sheffield S3 7RH (United Kingdom); Morton, R. J. [Mathematics and Information Science, Northumbria University, Camden Street, Newcastle Upon Tyne NE1 8ST (United Kingdom); Christian, D. J., E-mail: dkuridze01@qub.ac.uk [Department of Physics and Astronomy, California State University, Northridge, CA 91330 (United States)

    2013-12-10

    Using data obtained by the high temporal and spatial resolution Rapid Oscillations in the Solar Atmosphere instrument on the Dunn Solar Telescope, we investigate at an unprecedented level of detail transverse oscillations in chromospheric fine structures near the solar disk center. The oscillations are interpreted in terms of propagating and standing magnetohydrodynamic kink waves. Wave characteristics including the maximum transverse velocity amplitude and the phase speed are measured as a function of distance along the structure's length. Solar magnetoseismology is applied to these measured parameters to obtain diagnostic information on key plasma parameters (e.g., magnetic field, density, temperature, flow speed) of these localized waveguides. The magnetic field strength of the mottle along the ?2 Mm length is found to decrease by a factor of 12, while the local plasma density scale height is ?280 ± 80 km.

  6. Case History Imaging permafrost velocity structure using high resolution

    E-Print Network [OSTI]

    Ramachandran, Kumar

    horizontal and vertical checkerboard tests confirm the robustness of the velocity model in detailing small the permafrost velocity structure in lateral and vertical directions. It is inferred from the velocity model reflection data. More specifically, geothermal heterogeneities within the permafrost are associated

  7. Seismic Velocity Estimation from Time Migration Maria Kourkina Cameron

    E-Print Network [OSTI]

    Cameron, Maria Kourkina

    Seismic Velocity Estimation from Time Migration by Maria Kourkina Cameron Diplom (Moscow Institute Dung-Hai Lee Spring 2007 #12;Seismic Velocity Estimation from Time Migration Copyright c 2007 by Maria Kourkina Cameron #12;Abstract Seismic Velocity Estimation from Time Migration by Maria Kourkina Cameron

  8. Propagation and dispersion of sausage wave trains in magnetic flux tubes

    E-Print Network [OSTI]

    Oliver, R; Terradas, J

    2015-01-01

    A localized perturbation of a magnetic flux tube produces a pair of wave trains that propagate in opposite directions along the tube. These wave packets disperse as they propagate, where the extent of dispersion depends on the physical properties of the magnetic structure, on the length of the initial excitation, and on its nature (e.g., transverse or axisymmetric). In Oliver et al. (2014) we considered a transverse initial perturbation, whereas the temporal evolution of an axisymmetric one is examined here. In both papers we use a method based on Fourier integrals to solve the initial value problem. Previous studies on wave propagation in magnetic wave guides have emphasized that the wave train dispersion is influenced by the particular dependence of the group velocity on the longitudinal wavenumber. Here we also find that long initial perturbations result in low amplitude wave packets and that large values of the magnetic tube to environment density ratio yield longer wave trains. To test the detectability ...

  9. Parametric instabilities of large-amplitude parallel propagating Alfven waves: 2-D PIC simulation

    E-Print Network [OSTI]

    Yasuhiro Nariyuki; Shuichi Matsukiyo; Tohru Hada

    2008-04-25

    We discuss the parametric instabilities of large-amplitude parallel propagating Alfven waves using the 2-D PIC simulation code. First, we confirmed the results in the past study [Sakai et al, 2005] that the electrons are heated due to the modified two stream instability and that the ions are heated by the parallel propagating ion acoustic waves. However, although the past study argued that such parallel propagating longitudinal waves are excited by transverse modulation of parent Alfven wave, we consider these waves are more likely to be generated by the usual, parallel decay instability. Further, we performed other simulation runs with different polarization of the parent Alfven waves or the different ion thermal velocity. Numerical results suggest that the electron heating by the modified two stream instability due to the large amplitude Alfven waves is unimportant with most parameter sets.

  10. Three-dimensional P and S waves velocity structures of the Coso geothermal

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013)Open Energy Information Three dimensional seismic

  11. Earthq Sci (2010)23: 449-463 449 Three dimensional shear wave velocity structure of

    E-Print Network [OSTI]

    Song, Xiaodong

    2010-01-01

    of Illinois at Urbana-Champaign, Urbana IL 61801, USA 2 Institute of Earthquake Science, China Earthquake of the Pacific and Philippine plates led to the formation of island arcs and continental rift zones. Between

  12. Accurate seismic phase-velocities from interfering surface-waves using homomorphic deconvolution 

    E-Print Network [OSTI]

    Szerbiak, Robert Bruce

    1981-01-01

    (1 ? bkz) X(z) = Az & k=1 k=1 27 Pi Po (1-ckz ) & (1-dkz k= 1 k= 1 (31) where k k -1 k -1 k m. i Pi m 0 Po DC component, linear-phase component, zeroes inside the unit circle, ized & saki poles inside the unit circle, )zi & ~cki...

  13. Nonlinear pulse propagation and phase velocity of laser-driven plasma waves

    E-Print Network [OSTI]

    Schroeder, Carl B.

    2011-01-01

    of California. Nonlinear pulse propagation and phasea relativistically-intense short-pulse laser in un- derdenseinvestigated in the broad pulse limit, including the e?ects

  14. Thermal structure of continental upper mantle inferred from S-wave velocity and surface heat ow

    E-Print Network [OSTI]

    Snieder, Roel

    ; geothermal gradient 1. Introduction Oceanic lithosphere is continuously recycled by mantle convection geotherms differ most at depths of 60^120 km with variations of up to 900³C. Below 230 km, differences do not exceed 300³C. These geotherms agree well with one-dimensional conductive geotherms for the observed range

  15. P wave velocity variations in the Coso region, California, derived from

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QAsource History ViewMayo, Maryland:NPIProtectio Program | OpenWisconsin:NewOver CoreOxfordlocal earthquake travel

  16. Crust and Upper Mantle P Wave Velocity Structure Beneath Valles Caldera,

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTIONRobertsdale, Alabama (Utility Company)|Alabama:Crofton, Maryland:Crownsville, Maryland:Crugers,New

  17. Cycloidal Wave Energy Converter

    SciTech Connect (OSTI)

    Stefan G. Siegel, Ph.D.

    2012-11-30

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

  18. THE EFFECT OF THE PRE-DETONATION STELLAR INTERNAL VELOCITY PROFILE ON THE NUCLEOSYNTHETIC YIELDS IN TYPE Ia SUPERNOVA

    SciTech Connect (OSTI)

    Kim, Yeunjin; Jordan, G. C. IV; Graziani, Carlo; Lamb, D. Q.; Truran, J. W.; Meyer, B. S.

    2013-07-01

    A common model of the explosion mechanism of Type Ia supernovae is based on a delayed detonation of a white dwarf. A variety of models differ primarily in the method by which the deflagration leads to a detonation. A common feature of the models, however, is that all of them involve the propagation of the detonation through a white dwarf that is either expanding or contracting, where the stellar internal velocity profile depends on both time and space. In this work, we investigate the effects of the pre-detonation stellar internal velocity profile and the post-detonation velocity of expansion on the production of {alpha}-particle nuclei, including {sup 56}Ni, which are the primary nuclei produced by the detonation wave. We perform one-dimensional hydrodynamic simulations of the explosion phase of the white dwarf for center and off-center detonations with five different stellar velocity profiles at the onset of the detonation. In order to follow the complex flows and to calculate the nucleosynthetic yields, approximately 10,000 tracer particles were added to every simulation. We observe two distinct post-detonation expansion phases: rarefaction and bulk expansion. Almost all the burning to {sup 56}Ni occurs only in the rarefaction phase, and its expansion timescale is influenced by pre-existing flow structure in the star, in particular by the pre-detonation stellar velocity profile. We find that the mass fractions of the {alpha}-particle nuclei, including {sup 56}Ni, are tight functions of the empirical physical parameter {rho}{sub up}/v{sub down}, where {rho}{sub up} is the mass density immediately upstream of the detonation wave front and v{sub down} is the velocity of the flow immediately downstream of the detonation wave front. We also find that v{sub down} depends on the pre-detonation flow velocity. We conclude that the properties of the pre-existing flow, in particular the internal stellar velocity profile, influence the final isotopic composition of burned matter produced by the detonation.

  19. An integrable evolution equation for surface waves in deep water

    E-Print Network [OSTI]

    R. Kraenkel; H. Leblond; M. A. Manna

    2011-01-30

    In order to describe the dynamics of monochromatic surface waves in deep water, we derive a nonlinear and dispersive system of equations for the free surface elevation and the free surface velocity from the Euler equations in infinite depth. From it, and using a multiscale perturbative methods, an asymptotic model for small-aspect-ratio waves is derived. The model is shown to be completely integrable. The Lax pair, the first conserved quantities as well as the symmetries are exhibited. Theoretical and numerical studies reveal that it supports periodic progressive Stokes waves which peak and break in finite time. Comparison between the limiting wave solution of the asymptotic model and classical irrotational results is performed.

  20. Obliquely propagating electromagnetic waves in magnetized kappa plasmas

    E-Print Network [OSTI]

    Gaelzer, Rudi

    2015-01-01

    Velocity distribution functions (VDFs) that exhibit a power-law dependence on the high-energy tail have been the subject of intense research by the plasma physics community. Such functions, known as kappa or superthermal distributions, have been found to provide a better fitting to the VDFs measured by spacecraft in the solar wind. One of the problems that is being addressed on this new light is the temperature anisotropy of solar wind protons and electrons. In the literature, the general treatment for waves excited by (bi-)Maxwellian plasmas is well-established. However, for kappa distributions, the wave characteristics have been studied mostly for the limiting cases of purely parallel or perpendicular propagation, relative to the ambient magnetic field. Contributions to the general case of obliquely-propagating electromagnetic waves have been scarcely reported so far. The absence of a general treatment prevents a complete analysis of the wave-particle interaction in kappa plasmas, since some instabilities c...

  1. The Force of a Tsunami on a Wave Energy Converter

    E-Print Network [OSTI]

    O'Brien, Laura; Renzi, Emiliano; Dutykh, Denys; Dias, Frédéric

    2012-01-01

    With an increasing emphasis on renewable energy resources, wave power technology is fast becoming a realistic solution. However, the recent tsunami in Japan was a harsh reminder of the ferocity of the ocean. It is known that tsunamis are nearly undetectable in the open ocean but as the wave approaches the shore its energy is compressed creating large destructive waves. The question posed here is whether a nearshore wave energy converter (WEC) could withstand the force of an incoming tsunami. The analytical 3D model of Renzi & Dias (2012) developed within the framework of a linear theory and applied to an array of fixed plates is used. The time derivative of the velocity potential allows the hydrodynamic force to be calculated.

  2. In-phase waves: Their behavior, internal stratification and fabric

    SciTech Connect (OSTI)

    Cheel, R.J. (Brock Univ., St. Catharines, Ontario (Canada). Dept. of Earth Sciences); Udri, A. (Freiburg Univ. (Germany). Dept. of Geologie)

    1993-03-01

    Experiments were conducted in 0.305m wide, 9m long recirculating sediment flume on a bed of quartz sand (mean diameter of 0.18mm). The experiments included eight runs over the following range of conditions: 0.0605m [<=] depth [<=] 0.068m, 0.51m/s [<=] mean flow velocity [<=] 0.90m/s and 0.63 [<=] Froze Number (F) [<=] 1.1. For F < 0.83 dunes were the dominant bedform and these became longer and lower as F increased. At F = 0.83 the bed was nominally plane but locally and temporarily developed low in-phase waves or dunes. Post-run bed profiles showed symmetrical bedwaves with average length (L) of 0.26m and average height (H) of 0.005m. A complete cycle was characterized by: increased height of bed and water surface waves [r arrow] upstream migration [r arrow] breaking or decay [r arrow] planing of bed surface [r arrow] growth of new in-phase waves (initially migrating downstream and then remaining stationary during continued vertical growth). Each in-phase wave normally behaved independently of other waves although less commonly a breaking wave would trigger breaking of the next downstream wave. For F > 1.0 in-phase waves behaved as described above but a breaking wave would more commonly cause breaking of other waves. With increasing F it became more common for waves to break and rebuild quickly without complete planing of the bed surface. However, complete cycles occurred frequently with the following significant differences: (1) the upstream-migrating antidune developed upstream slopes that approached 25[degree]; (2) planing was accomplished by the rapid migration of a low, asymmetrical bedform through the antidune trough.

  3. Time-domain detection of superluminal group velocity for single microwave pulses Mohammad Mojahedi, Edl Schamiloglu, Frank Hegeler, and Kevin J. Malloy

    E-Print Network [OSTI]

    Mojahedi, Mohammad

    as the Sommerfeld forerunner, remain exactly luminal. The frequency of oscillations and the functional form, their delineation of the concept of wave velocity into such terms as phase, group, energy, and forerunner both. However, by their own admission such a definition is arbi- trary 1 , p. 79 , and as we will see

  4. Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes...

    Office of Environmental Management (EM)

    Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Atom-Probe Tomographic Measurement of Trapped Hydrogen Isotopes Presentation from the 34th Tritium Focus Group...

  5. MHD waves in sunspots

    E-Print Network [OSTI]

    Sych, Robert

    2015-01-01

    The review addresses the spatial frequency morphology of sources of sunspot oscillations and waves, including their localization, size, oscillation periods, height localization with the mechanism of cut-off frequency that forms the observed emission variability. Dynamic of sunspot wave processes, provides the information about the structure of wave fronts and their time variations, investigates the oscillation frequency transformation depending on the wave energy is shown. The initializing solar flares caused by trigger agents like magnetoacoustic waves, accelerated particle beams, and shocks are discussed. Special attention is paid to the relation between the flare reconnection periodic initialization and the dynamics of sunspot slow magnetoacoustic waves. A short review of theoretical models of sunspot oscillations is provided.

  6. The Earth's velocity for direct detection experiments

    E-Print Network [OSTI]

    Christopher McCabe

    2014-02-26

    The Earth's velocity relative to the Sun in galactic coordinates is required in the rate calculation for direct detection experiments. We provide a rigorous derivation of this quantity to first order in the eccentricity of the Earth's orbit. We also discuss the effect of the precession of the equinoxes, which has hitherto received little explicit discussion. Comparing with other expressions in the literature, we confirm that the expression of Lee, Lisanti and Safdi is correct, while the expression of Lewin and Smith, the de facto standard expression, contains an error. For calculations of the absolute event rate, the leading order expression is sufficient while for modulation searches, an expression with the eccentricity is required for accurate predictions of the modulation phase.

  7. Filament velocity scaling laws for warm ions

    SciTech Connect (OSTI)

    Manz, P.; Max-Planck-Institut für Plasmaphysik, EURATOM Assoziation, Boltzmannstr. 2, 85748 Garching ; Carralero, D.; Birkenmeier, G.; Müller, H. W.; Scott, B. D.; Müller, S. H.; Fuchert, G.; Stroth, U.; Physik-Department E28, Technische Universität München, James-Franck-Str. 1, 85748 Garching

    2013-10-15

    The dynamics of filaments or blobs in the scrape-off layer of magnetic fusion devices are studied by magnitude estimates of a comprehensive drift-interchange-Alfvén fluid model. The standard blob models are reproduced in the cold ion case. Even though usually neglected, in the scrape-off layer, the ion temperature can exceed the electron temperature by an order of magnitude. The ion pressure affects the dynamics of filaments amongst others by adding up to the interchange drive and the polarisation current. It is shown how both effects modify the scaling laws for filament velocity in dependence of its size. Simplifications for experimentally relevant limit regimes are given. These are the sheath dissipation, collisional, and electromagnetic regime.

  8. 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 and experimental work on dust acoustic waves is given. The basic physics of the dust acoustic wave and some findings and outstanding problems are also presented. Keywords: dusty plasmas, dust acoustic waves PACS: 52

  9. 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

  10. 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

  11. REAL-TIME WATER WAVES WITH WAVE PARTICLES

    E-Print Network [OSTI]

    Keyser, John

    REAL-TIME WATER WAVES WITH WAVE PARTICLES A Dissertation by Cem Yuksel Submitted to the Office of DOCTOR OF PHILOSOPHY August 2010 Major Subject: Computer Science #12;REAL-TIME WATER WAVES WITH WAVE, Valerie E. Taylor August 2010 Major Subject: Computer Science #12;iii ABSTRACT Real-time Water Waves

  12. GN Wave theory and TEBEM for Wave-Body Interaction

    E-Print Network [OSTI]

    GN Wave theory and TEBEM for Wave-Body Interaction Dr. BinBin Zhao and Professor Wenyang Duan of simulating irregular nonlinear water wave interaction with arbitrary floating bodies, the Green-Naghdi wave corners. The results show that the high-level GN theory can predict wave transformation over uneven seabed

  13. Trimodal steady water waves

    E-Print Network [OSTI]

    Mats Ehrnström; Erik Wahlén

    2013-10-31

    We construct three-dimensional families of small-amplitude gravity-driven rotational steady water waves on finite depth. The solutions contain counter-currents and multiple crests in each minimal period. Each such wave generically is a combination of three different Fourier modes, giving rise to a rich and complex variety of wave patterns. The bifurcation argument is based on a blow-up technique, taking advantage of three parameters associated with the vorticity distribution, the strength of the background stream, and the period of the wave.

  14. Granular rotor as a probe for a non-equilibrium bath

    E-Print Network [OSTI]

    Tomohiko G. Sano; Kiyoshi Kanazawa; Hisao Hayakawa

    2015-11-27

    The dynamics of a rotor under viscous or dry friction is investigated as a non-equilibrium probe of a granular gas numerically and analytically. To demonstrate a role of the rotor as a probe for a non-equilibrium bath, we perform the molecular dynamics (MD) simulation of the rotor under viscous or dry friction surrounded by a steady granular gas under gravity. We theoretically derive a one-to-one map between the velocity distribution function (VDF) for the granular gas and the angular one for the rotor. With the aid of the MD simulation, we demonstrate that the one-to-one map works well to infer the local VDF of the granular gas from the angular one of the rotor, and vice versa.

  15. Peculiarity of convergence of shock wave generated by underwater electrical explosion of ring-shaped wire

    SciTech Connect (OSTI)

    Shafer, D.; Toker, G. R.; Gurovich, V. Tz.; Gleizer, S.; Krasik, Ya. E.

    2013-05-15

    Nanosecond timescale underwater electrical wire explosions of ring-shaped Cu wires were investigated using a pulsed generator with a current amplitude up to 50 kA. It was shown that this type of wire explosion results in the generation of a toroidal shock wave (SW). Time- and space-resolved optical diagnostics were used to determine azimuthal uniformity of the shock wave front and its velocity. It was found that the shock wave preserves its circular front shape in the range of radii 50?mwave propagates with a constant velocity of v{sub sw}=1.2M, where M is the Mach number. The dynamics of the leading part of the shock wave, based on the oblique shock wave theory, is presented, explaining the constant velocity of the shock wave.

  16. System and method to estimate compressional to shear velocity (VP/VS) ratio in a region remote from a borehole

    DOE Patents [OSTI]

    Vu, Cung; Nihei, Kurt T; Schmitt, Denis P; Skelt, Christopher; Johnson, Paul A; Guyer, Robert; TenCate, James A; Le Bas, Pierre-Yves

    2012-10-16

    In some aspects of the disclosure, a method for creating three-dimensional images of non-linear properties and the compressional to shear velocity ratio in a region remote from a borehole using a conveyed logging tool is disclosed. In some aspects, the method includes arranging a first source in the borehole and generating a steered beam of elastic energy at a first frequency; arranging a second source in the borehole and generating a steerable beam of elastic energy at a second frequency, such that the steerable beam at the first frequency and the steerable beam at the second frequency intercept at a location away from the borehole; receiving at the borehole by a sensor a third elastic wave, created by a three wave mixing process, with a frequency equal to a difference between the first and second frequencies and a direction of propagation towards the borehole; determining a location of a three wave mixing region based on the arrangement of the first and second sources and on properties of the third wave signal; and creating three-dimensional images of the non-linear properties using data recorded by repeating the generating, receiving and determining at a plurality of azimuths, inclinations and longitudinal locations within the borehole. The method is additionally used to generate three dimensional images of the ratio of compressional to shear acoustic velocity of the same volume surrounding the borehole.

  17. Relativistic (covariant) kinetic theory of linear plasma waves and instabilities

    SciTech Connect (OSTI)

    Lazar, M. [Institut fuer Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); 'Alexandru Ioan Cuza' University, Faculty of Physics, 6600 Iasi (Romania); Schlickeiser, R. [Institut fuer Theoretische Physik, Lehrstuhl IV: Weltraum- und Astrophysik, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Centre for Plasma Science and Astrophysics, Ruhr-University, D-44780 Bochum (Germany)

    2006-06-19

    The fundamental kinetic description is of vital importance in high-energy astrophysics and fusion plasmas where wave phenomena evolve on scales small comparing with binary collision scales. A rigorous relativistic analysis is required even for nonrelativistic plasma temperatures for which the classical theory yielded unphysical results: e.g. collisonless damping of superluminal waves (phase velocity exceeds the speed of light). The existing nonrelativistic approaches are now improved by covariantly correct dispersion theory. As an important application, the Weibel instability has been recently investigated and confirmed as the source of primordial magnetic field in the intergalactic medium.

  18. Quantum metamaterials: Electromagnetic waves in a Josephson qubit line

    E-Print Network [OSTI]

    A. L. Rakhmanov; A. M. Zagoskin; Sergey Savel'ev; Franco Nori

    2007-12-19

    We consider the propagation of a classical electromagnetic wave through a transmission line, formed by identical superconducting charge qubits inside a superconducting resonator. Since the qubits can be in a coherent superposition of quantum states, we show that such a system demonstrates interesting new effects, such as a ``breathing'' photonic crystal with an oscillating bandgap, and a ``quantum Archimedean screw'' that transports, at an arbitrary controlled velocity, Josephson plasma waves through the transmission line. The key ingredient of these effects is that the optical properties of the Josephson transmission line are controlled by the quantum coherent state of the qubits.

  19. Catheter based magnetic resonance compatible perfusion probe

    E-Print Network [OSTI]

    Toretta, Cara Lynne

    2007-01-01

    Neurosurgeons are using a thermal based technique to quantify brain perfusion. The thermal diffusion probe (TDP) technology measures perfusion in a relatively small volume of brain tissue. The neurosurgeon chooses the ...

  20. Self-referencing remote optical probe

    DOE Patents [OSTI]

    O'Rourke, P.E.; Prather, W.S.; Livingston, R.R.

    1991-08-13

    A probe is described for remote spectrometric measurements of fluid samples having a hollow probe body with a sliding reflective plug therein and a lens at one end, ports for admitting and expelling the fluid sample and a means for moving the reflector so that reference measurement can be made with the reflector in a first position near the lens and a sample measurement can be made with the reflector away from the lens and the fluid sample between the reflector and the lens. Comparison of the two measurements will yield the composition of the fluid sample. The probe is preferably used for remote measurements and light is carried to and from the probe via fiber optic cables. 3 figures.

  1. Modulated microwave microscopy and probes used therewith

    DOE Patents [OSTI]

    Lai, Keji; Kelly, Michael; Shen, Zhi-Xun

    2012-09-11

    A microwave microscope including a probe tip electrode vertically positionable over a sample and projecting downwardly from the end of a cantilever. A transmission line connecting the tip electrode to the electronic control system extends along the cantilever and is separated from a ground plane at the bottom of the cantilever by a dielectric layer. The probe tip may be vertically tapped near or at the sample surface at a low frequency and the microwave signal reflected from the tip/sample interaction is demodulated at the low frequency. Alternatively, a low-frequency electrical signal is also a non-linear electrical element associated with the probe tip to non-linearly interact with the applied microwave signal and the reflected non-linear microwave signal is detected at the low frequency. The non-linear element may be semiconductor junction formed near the apex of the probe tip or be an FET formed at the base of a semiconducting tip.

  2. Configurations of polymers attached to probes

    E-Print Network [OSTI]

    Bubis, Roy

    We study polymers attached to spherical (circular) or paraboloidal (parabolic) probes in three (two) dimensions. Both self-avoiding and random walks are examined numerically. The behavior of a polymer of size R[subscript ...

  3. Surface sampling concentration and reaction probe

    DOE Patents [OSTI]

    Van Berkel, Gary J; Elnaggar, Mariam S

    2013-07-16

    A method of analyzing a chemical composition of a specimen is described. The method can include providing a probe comprising an outer capillary tube and an inner capillary tube disposed co-axially within the outer capillary tube, where the inner and outer capillary tubes define a solvent capillary and a sampling capillary in fluid communication with one another at a distal end of the probe; contacting a target site on a surface of a specimen with a solvent in fluid communication with the probe; maintaining a plug volume proximate a solvent-specimen interface, wherein the plug volume is in fluid communication with the probe; draining plug sampling fluid from the plug volume through the sampling capillary; and analyzing a chemical composition of the plug sampling fluid with an analytical instrument. A system for performing the method is also described.

  4. 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

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

    E-Print Network [OSTI]

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

    2014-01-01

    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...

  6. Wave-Corpuscle Mechanics for Electric Charges

    E-Print Network [OSTI]

    Babin, Anatoli; Figotin, Alexander

    2010-01-01

    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

  7. Microstructural Design for Stress Wave Energy Management /

    E-Print Network [OSTI]

    Tehranian, Aref

    2013-01-01

    Nasser, S. , 2010. Stress-wave energy management throughNemat-Nasser, Stress-wave energy management through materialconstitute pressure wave energy and/or shear wave energy.

  8. Tropical waves in a GCM with zonal symmetry

    SciTech Connect (OSTI)

    Yip, K.J.J.; North, G.R. (Texas A M Univ., College Station, TX (United States))

    1993-09-01

    Tropical wave phenomena have been examined in the last 520 days of two 15-year runs of a low-resolution general circulation model (CCMO). The model boundary conditions were simplified to all-land, perpetual equinox, and no topography. The two runs were for fixed soil moisture at 75% and 0%, the so-called [open quotes]wet[close quotes] and [open quotes]dry[close quotes] models. Both models develop well-defined ITCZs with low-level convergence erratically concentrated along the equator. Highly organized eastward-propagating waves are detectable in both models with different wave speeds depending on the presence of moisture. The wave amplitudes (in, e.g., vertical velocity) are many orders of magnitude stronger in the wet model. The waves have a definite transverse nature as precipitation (low-level convergence) patches tend to move systematically north and south across the equator. In the wet model the waves are distinctly nondispersive and the transit time for passage around the earth is about 50 days, consistent with the Madden-Julian frequency. The authors are also able to see most of the expected linear wave modes in spectral density plots in the frequency-wavenumber plane and compare them for the wet and dry cases. 28 refs., 16 figs.

  9. Evidence for wave heating of the quiet-sun corona

    SciTech Connect (OSTI)

    Hahn, M.; Savin, D. W.

    2014-11-10

    We have measured the energy and dissipation of Alfvénic waves in the quiet Sun. A magnetic field model was used to infer the location and orientation of the magnetic field lines along which the waves are expected to travel. The waves were measured using spectral lines to infer the wave amplitude. The waves cause a non-thermal broadening of the spectral lines, which can be expressed as a non-thermal velocity v {sub nt}. By combining the spectroscopic measurements with this magnetic field model, we were able to trace the variation of v {sub nt} along the magnetic field. At each footpoint of the quiet-Sun loops, we find that waves inject an energy flux in the range of 1.3-5.5 × 10{sup 5} erg cm{sup –2} s{sup –1}. At the minimum of this range, this amounts to more than 80% of the energy needed to heat the quiet Sun. We also find that these waves are dissipated over a region centered on the top of the loops. The position along the loop where the damping begins is strongly correlated with the length of the loop, implying that the damping mechanism depends on the global loop properties rather than on local collisional dissipation.

  10. Branching actin network remodeling governs the force-velocity relationship

    E-Print Network [OSTI]

    Daniel B. Smith; Jian Liu

    2011-11-28

    Actin networks, acting as an engine pushing against an external load, are fundamentally important to cell motility. A measure of the effectiveness of an engine is the velocity the engine is able to produce at a given force, the force-velocity curve. One type of force-velocity curve, consisting of a concave region where velocity is insensitive to increasing force followed by a decrease in velocity, is indicative of an adaptive response. In contrast, an engine whose velocity rapidly decays as a convex curve in response to increasing force would indicate a lack of adaptive response. Even taken outside of a cellular context, branching actin networks have been observed to exhibit both concave and convex force-velocity curves. The exact mechanism that can explain both force-velocity curves is not yet known. We carried out an agent-based stochastic simulation to explore such a mechanism. Our results suggest that upon loading, branching actin networks are capable of remodeling by increasing the number filaments growing against the load. Our model provides a mechanism that can account for both convex and concave force-velocity relationships observed in branching actin networks. Finally, our model gives a potential explanation to the experimentally observed force history dependence for actin network velocity.

  11. The Hera Saturn Entry Probe Mission

    E-Print Network [OSTI]

    Mousis, O; Spilker, T; Venkatapathy, E; Poncy, J; Frampton, R; Coustenis, A; Reh, K; Lebreton, J -P; Fletcher, L N; Hueso, R; Amato, M J; Colaprete, A; Ferri, F; Stam, D; Wurz, P; Atreya, S; Aslam, S; Banfield, D J; Calcutt, S; Fischer, G; Holland, A; Keller, C; Kessler, E; Leese, M; Levacher, P; Morse, A; Munoz, O; Renard, J -B; Sheridan, S; Schmider, F -X; Snik, F; Waite, J H; Bird, M; Cavalié, T; Deleuil, M; Fortney, J; Gautier, D; Guillot, T; Lunine, J I; Marty, B; Nixon, C; Orton, G S; Sanchez-Lavega, A

    2015-01-01

    The Hera Saturn entry probe mission is proposed as an M--class mission led by ESA with a contribution from NASA. It consists of one atmospheric probe to be sent into the atmosphere of Saturn, and a Carrier-Relay spacecraft. In this concept, the Hera probe is composed of ESA and NASA elements, and the Carrier-Relay Spacecraft is delivered by ESA. The probe is powered by batteries, and the Carrier-Relay Spacecraft is powered by solar panels and batteries. We anticipate two major subsystems to be supplied by the United States, either by direct procurement by ESA or by contribution from NASA: the solar electric power system (including solar arrays and the power management and distribution system), and the probe entry system (including the thermal protection shield and aeroshell). Hera is designed to perform in situ measurements of the chemical and isotopic compositions as well as the dynamics of Saturn's atmosphere using a single probe, with the goal of improving our understanding of the origin, formation, and ev...

  12. Fiber optic probe for light scattering measurements

    DOE Patents [OSTI]

    Nave, Stanley E. (Evans, GA); Livingston, Ronald R. (Aiken, SC); Prather, William S. (Augusta, GA)

    1995-01-01

    A fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman-scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

  13. Fiber optic probe for light scattering measurements

    DOE Patents [OSTI]

    Nave, S.E.; Livingston, R.R.; Prather, W.S.

    1993-01-01

    This invention is comprised of a fiber optic probe and a method for using the probe for light scattering analyses of a sample. The probe includes a probe body with an inlet for admitting a sample into an interior sample chamber, a first optical fiber for transmitting light from a source into the chamber, and a second optical fiber for transmitting light to a detector such as a spectrophotometer. The interior surface of the probe carries a coating that substantially prevents non-scattered light from reaching the second fiber. The probe is placed in a region where the presence and concentration of an analyte of interest are to be detected, and a sample is admitted into the chamber. Exciting light is transmitted into the sample chamber by the first fiber, where the light interacts with the sample to produce Raman-scattered light. At least some of the Raman- scattered light is received by the second fiber and transmitted to the detector for analysis. Two Raman spectra are measured, at different pressures. The first spectrum is subtracted from the second to remove background effects, and the resulting sample Raman spectrum is compared to a set of stored library spectra to determine the presence and concentration of the analyte.

  14. Asymmetric material impact: Achieving free surfaces velocities nearly double that of the projectile

    SciTech Connect (OSTI)

    Aslam, Tariq; Dattelbaum, Dana; Gustavsen, Richard; Scharff, Robert; Byers, Mark

    2015-05-19

    Hypervelocity impact speeds are often limited by practical considerations in guns and explosive driven systems. In particular, for gas guns (both powder driven and light gas guns), there is the general trend that higher projectile speeds often come at the expense of smaller diameters, and thus less time for examining shock phenomena prior to two dimensional release waves affecting the observed quantities of interest. Similarly, explosive driven systems have their own set of limiting conditions due to limitations in explosive energy and size of devices required as engineering dimensions increase. The focus in this study is to present a methodology of obtaining free surface velocities well in excess of the projectile velocity. The key to this approach is in using a high impedance projectile that impacts a series of progressively lower impedance materials. The free surface velocity (if they were separated) of each of the progressively lower impedance materials would increase for each material. The theory behind this approach, as well as experimental results are presented.

  15. Asymmetric material impact: Achieving free surfaces velocities nearly double that of the projectile

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

    Aslam, Tariq; Dattelbaum, Dana; Gustavsen, Richard; Scharff, Robert; Byers, Mark

    2015-05-19

    Hypervelocity impact speeds are often limited by practical considerations in guns and explosive driven systems. In particular, for gas guns (both powder driven and light gas guns), there is the general trend that higher projectile speeds often come at the expense of smaller diameters, and thus less time for examining shock phenomena prior to two dimensional release waves affecting the observed quantities of interest. Similarly, explosive driven systems have their own set of limiting conditions due to limitations in explosive energy and size of devices required as engineering dimensions increase. The focus in this study is to present a methodologymore »of obtaining free surface velocities well in excess of the projectile velocity. The key to this approach is in using a high impedance projectile that impacts a series of progressively lower impedance materials. The free surface velocity (if they were separated) of each of the progressively lower impedance materials would increase for each material. The theory behind this approach, as well as experimental results are presented.« less

  16. Asymmetric material impact: Achieving free surfaces velocities nearly double that of the projectile

    SciTech Connect (OSTI)

    Aslam, Tariq [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dattelbaum, Dana [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Gustavsen, Richard [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Scharff, Robert [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Byers, Mark [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-01-01

    Hypervelocity impact speeds are often limited by practical considerations in guns and explosive driven systems. In particular, for gas guns (both powder driven and light gas guns), there is the general trend that higher projectile speeds often come at the expense of smaller diameters, and thus less time for examining shock phenomena prior to two dimensional release waves affecting the observed quantities of interest. Similarly, explosive driven systems have their own set of limiting conditions due to limitations in explosive energy and size of devices required as engineering dimensions increase. The focus in this study is to present a methodology of obtaining free surface velocities well in excess of the projectile velocity. The key to this approach is in using a high impedance projectile that impacts a series of progressively lower impedance materials. The free surface velocity (if they were separated) of each of the progressively lower impedance materials would increase for each material. The theory behind this approach, as well as experimental results, are presented.

  17. Harmonic generation of gravitational wave induced Alfven waves

    E-Print Network [OSTI]

    Mats Forsberg; Gert Brodin

    2007-11-26

    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.

  18. Electromagnetic Wave Dynamics in

    E-Print Network [OSTI]

    Kaiser, Robin

    Mesoscopic Electromagnetic Wave Dynamics in Ultracold Atomic Gases Robin Kaiser and Mark D. Havey Mesoscopic Electromagnetic Wave Dynamics in Ultracold Atomic Gases #12;39 E xperimental developments permit in the transport proper- ties of electromagnetic radiation in strongly scattering random media. Even in weakly

  19. CATCHING THE FOURTH WAVE

    E-Print Network [OSTI]

    Bieber, Michael

    CATCHING THE FOURTH WAVE YOU MAY HAVE RIDDEN THEM YOURSELF -- the swells that develop farther out beyond Toffler, the fourth wave -- biologi- cal intelligence and medical technology -- is on the horizon second and fourth nationally in terms of cities that receive the most research funds from the National

  20. A semiclassical study of wave packet dynamics in anharmonic potentials Shilong Yang, Jianshu Cao,a)

    E-Print Network [OSTI]

    Cao, Jianshu

    method, specifically designed for the purpose of computing pump-probe signals, and demonstrate its profile at the left-turning point without actual wave packet propagation, revealing a quantum mechanical elementary chemical processes at the molecular level. With femtosecond laser pulses it is now possible