Propagation Analysis of Electromagnetic Waves: Application to Auroral Kilometric Radiation
Santolik, Ondrej
12 Propagation Analysis of Electromagnetic Waves: Application to Auroral Kilometric Radiation, containing waves which simultaneously propagate in different directions and/or wave modes the concept emission is found to propagate predominantly in the R-X mode with wave energy distributed in relatively
Bulaevskii, L. N.; Kosehlev, A. E.; Tachiki, M.; Materials Science Division; LANL; Univ. of Tokyo
2008-01-01T23:59:59.000Z
Single crystals of layered high-temperature superconductors intrinsically behave as stacks of Josephson junctions. We analyze response of current-biased stack of intrinsic junctions to irradiation by the external electromagnetic (em) wave. In addition to well-known Shapiro steps in the current-voltage characteristics, irradiation promotes stimulated radiation which adds with spontaneous Josephson radiation from the crystal. Such enhancement of radiation from current-biased crystal may be used for amplification of em waves. Irradiation also facilitates synchronization of Josephson oscillations in all intrinsic Josephson junctions of a single crystal as well as oscillations in intrinsic junctions of different crystals.
Mitchell Revalski; Will Rhodes; Thulsi Wickramasinghe
2015-02-03T23:59:59.000Z
We provide calculations and theoretical arguments supporting the emission of electromagnetic radiation from charged particles accelerated by gravitational waves (GWs). These waves have significant indirect evidence to support their existence, yet they interact weakly with ordinary matter. We show that the induced oscillations of charged particles interacting with a GW, which lead to the emission of electromagnetic radiation, will also result in wave attenuation. These ideas are supported by a small body of literature, as well as additional arguments for particle acceleration based on GW memory effects. We derive order of magnitude power calculations for various initial charge distributions accelerated by GWs. The resulting power emission is extremely small for all but very strong GWs interacting with large quantities of charge. If the results here are confirmed and supplemented, significant consequences such as attenuation of early universe GWs could result. Additionally, this effect could extend GW detection techniques into the electromagnetic regime. These explorations are worthy of study to determine the presence of such radiation, as it is extremely important to refine our theoretical framework in an era of active GW astrophysics.
Reed, E J; Armstrong, M R; Kim, K Y; Glownia, J H; Howard, M; Piner, E; Roberts, J
2009-06-30T23:59:59.000Z
We present the first experimental observations of terahertz frequency radiation emitted when a terahertz frequency acoustic wave propagates past an interface between materials of differing piezoelectric coefficients. We show that this fundamentally new phenomenon can be used to probe structural properties of thin films. Then, we present molecular dynamics simulations showing that detectable THz frequency radiation can be emitted when a wurtzite structure crystal transforms to a rocksalt structure under shock compression on picosecond timescales. We show that information about the kinetics of the transformation is contained in the time-dependence of the THz field.
General Polarization Matrix of Electromagnetic Radiation
Muhammet Ali Can; Alexander S. Shumovsky
2001-05-15T23:59:59.000Z
A general form of the polarization matrix valid for any type of electromagnetic radiation (plane waves, multipole radiation etc.) is defined in terms of a certain bilinear form in the field-strength tensor. The quantum counterpart is determined as an operator matrix with normal-ordered elements with respect to the creation and annihilation operators. The zero-point oscillations (ZPO) of polarization are defined via difference between the anti-normal and normal ordered operator polarization matrices. It is shown that ZPO of the multipole field are stronger than those described by the model of plane waves and are concentrated in a certain neighborhood of a local source.
Electromagnetic signatures of far-field gravitational radiation in the 1+3 approach
Alvin J. K. Chua; Priscilla Cañizares; Jonathan R. Gair
2014-12-06T23:59:59.000Z
Gravitational waves from astrophysical sources can interact with background electromagnetic fields, giving rise to distinctive and potentially detectable electromagnetic signatures. In this paper, we study such interactions for far-field gravitational radiation using the 1+3 approach to relativity. Linearised equations for the electromagnetic field on perturbed Minkowski space are derived and solved analytically. The inverse Gertsenshtein conversion of gravitational waves in a static electromagnetic field is rederived, and the resultant electromagnetic radiation is shown to be significant for highly magnetised pulsars in compact binary systems. We also obtain a variety of nonlinear interference effects for interacting gravitational and electromagnetic waves, although wave-wave resonances previously described in the literature are absent when the electric-magnetic self-interaction is taken into account. The fluctuation and amplification of electromagnetic energy flux as the gravitational wave strength increases towards the gravitational-electromagnetic frequency ratio is a possible signature of gravitational radiation from extended astrophysical sources.
Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)
2012-12-15T23:59:59.000Z
Parametric decay of a large amplitude electromagnetic wave into two electromagnetic modes in a rippled density plasma channel is investigated. The channel is taken to possess step density profile besides a density ripple of axial wave vector. The density ripple accounts for the momentum mismatch between the interacting waves and facilitates nonlinear coupling. For a given pump wave frequency, the requisite ripple wave number varies only a little w.r.t. the frequency of the low frequency decay wave. The radial localization of electromagnetic wave reduces the growth rate of the parametric instability. The growth rate decreases with the frequency of low frequency electromagnetic wave.
ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD
Guedel, Manuel
ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD Manuel G¨udel 1 and Donat G. Wentzel 2 1 accelerated by a strong dc electric field show not only very efficient generation of beam waves but also emission of omode radiation. We present a set of particle simulations for which we study the behavior
Inferring black hole charge from backscattered electromagnetic radiation
Luís C. B. Crispino; Sam R. Dolan; Atsushi Higuchi; Ednilton S. de Oliveira
2014-09-16T23:59:59.000Z
We compute the scattering cross section of Reissner-Nordstr\\"om black holes for the case of an incident electromagnetic wave. We describe how scattering is affected by both the conversion of electromagnetic to gravitational radiation, and the parity-dependence of phase shifts induced by the black hole charge. The latter effect creates a helicity-reversed scattering amplitude that is non-zero in the backward direction. We show that from the character of the electromagnetic wave scattered in the backward direction it is possible, in principle, to infer if a static black hole is charged.
Counting energy packets in the electromagnetic wave
Stefan Popescu; Bernhard Rothenstein
2007-05-18T23:59:59.000Z
We discuss the concept of energy packets in respect to the energy transported by electromagnetic waves and we demonstrate that this physical quantity can be used in physical problems involving relativistic effects. This refined concept provides results compatible to those obtained by simpler definition of energy density when relativistic effects apply to the free electromagnetic waves. We found this concept further compatible to quantum theory perceptions and we show how it could be used to conciliate between different physical approaches including the classical electromagnetic wave theory, the special relativity and the quantum theories.
Surfatron acceleration of a relativistic particle by electromagnetic plane wave
A. I. Neishtadt; A. A. Vasiliev; A. V. Artemyev
2010-11-09T23:59:59.000Z
We study motion of a relativistic charged particle in a plane slow electromagnetic wave and background uniform magnetic field. The wave propagates normally to the background field. Under certain conditions, the resonance between the wave and the Larmor motion of the particle is possible. Capture into this resonance results in acceleration of the particle along the wave front (surfatron acceleration). We analyse the phenomenon of capture and show that a captured particle never leaves the resonance and its energy infinitely grows. Scattering on the resonance is also studied. We find that this scattering results in diffusive growth of the particle energy. Finally, we estimate energy losses due to radiation by an accelerated particle.
Cosmological electromagnetic fields due to gravitational wave perturbations Mattias Marklund*
Dunsby, Peter
show that this coupling leads to an initial pulse of electromagnetic waves whose width and amplitude to produce a pulse of gravitationally induced electromagnetic waves. In particular, because of the differentCosmological electromagnetic fields due to gravitational wave perturbations Mattias Marklund
The momentum of an electromagnetic wave inside a dielectric
Testa, Massimo, E-mail: massimo.testa@roma1.infn.it
2013-09-15T23:59:59.000Z
The problem of assigning a momentum to an electromagnetic wave packet propagating inside an insulator has become known under the name of the Abraham–Minkowski controversy. In the present paper we re-examine this issue making the hypothesis that the forces exerted on an insulator by an electromagnetic field do not distinguish between polarization and free charges. Under this assumption we show that the Abraham expression for the radiation mechanical momentum is highly favored. -- Highlights: •We discuss an approximation to treat electrodynamics of a dielectric material. •We support the Abraham form for the electromagnetic momentum. •We deduce Snell’s law from the conservation of the Abraham momentum. •We show how to deal with the electric field discontinuity at the dielectric boundary.
Dissipative electromagnetic solitary waves in collisional plasmas
Borhanian, Jafar [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P.O.Box 179, Ardabil (Iran, Islamic Republic of)
2012-08-15T23:59:59.000Z
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.
Pablo L. Saldanha
2010-02-04T23:59:59.000Z
It is proposed a natural and consistent division of the momentum of electromagnetic waves in linear, non-dispersive and non-absorptive dielectric and magnetic media into material and electromagnetic parts. The material part is calculated using directly the Lorentz force law and the electromagnetic momentum density has the same form than in vacuum, without an explicit dependence on the properties of the media. The consistency of the treatment is verified through the obtention of a correct momentum balance equation in many examples and showing the compatibility of the division with the Einstein's theory of relativity by the use of a gedanken experiment. An experimental prediction for the radiation pressure on mirrors immersed in linear dielectric and magnetic media is also made.
Saldanha, Pablo L
2009-01-01T23:59:59.000Z
It is proposed a natural and consistent division of the momentum of electromagnetic waves in linear, non-dispersive and non-absorptive dielectric and magnetic media into material and electromagnetic parts. The material part is calculated using directly the Lorentz force law and the electromagnetic momentum density has the same form than in vacuum, without an explicit dependence on the properties of the media. The consistency of the treatment is verified through the obtention of a correct momentum balance equation in many examples and showing the compatibility of the division with the Einstein's theory of relativity by the use of a gedanken experiment. An experimental prediction for the radiation pressure on mirrors immersed in linear dielectric and magnetic media is also made.
Electromagnetic Radiation and Motion of Real Particle
Jozef Klacka
2001-06-21T23:59:59.000Z
Relativistically covariant equation of motion for real dust particle under the action of electromagnetic radiation is derived. The particle is neutral in charge. Equation of motion is expressed in terms of particle's optical properties, standardly used in optics for stationary particles.
Mathematical Methods for Electromagnetic and Optical Waves1
Lu, Ya Yan
Mathematical Methods for Electromagnetic and Optical Waves1 Ya Yan Lu Department of Mathematics . . . . . . . . . . . . . . . . . . . . . . 5 1.6 The energy law of electromagnetic field . . . . . . . . . . . . . . . . . . . . . 7 2.5 Pulse propagation and temporal solitons . . . . . . . . . . . . . . . . . . . . . 70 2 #12;Chapter 1
Electromagnetic radiation from relativistic nuclear collisions
Charles Gale; Kevin L. Haglin
2003-06-16T23:59:59.000Z
We review some of the results obtained in the study of the production of electromagnetic radiation in relativistic nuclear collisions. We concentrate on the emission of real photons and dileptons from the hot and dense strongly interacting phases of the reaction. We examine the contributions from the partonic sector, as well as those from the nonperturbative hadronic sector. We examine the current data, some of the predictions for future measurements, and comment on what has been learnt so far.
Detecting excess ionizing radiation by electromagnetic breakdown of air
Granatstein, Victor L.; Nusinovich, Gregory S. [Center for Applied Electromagnetics, Institute for Research in Electronics and Applied Physics, University of Maryland, College Park, Maryland 20742 (United States)
2010-09-15T23:59:59.000Z
A scheme is proposed for detecting a concealed source of ionizing radiation by observing the occurrence of breakdown in atmospheric air by an electromagnetic wave whose electric field surpasses the breakdown field in a limited volume. The volume is chosen to be smaller than the reciprocal of the naturally occurring concentration of free electrons. The pulse duration of the electromagnetic wave must exceed the avalanche breakdown time (10-200 ns) and could profitably be as long as the statistical lag time in ambient air (typically, microseconds). Candidate pulsed electromagnetic sources over a wavelength range, 3 mm>{lambda}>10.6 {mu}m, are evaluated. Suitable candidate sources are found to be a 670 GHz gyrotron oscillator with 200 kW, 10 {mu}s output pulses and a Transversely Excited Atmospheric-Pressure (TEA) CO{sub 2} laser with 30 MW, 100 ns output pulses. A system based on 670 GHz gyrotron would have superior sensitivity. A system based on the TEA CO{sub 2} laser could have a longer range >100 m.
Electromagnetic Radiation Hardness of Diamond Detectors
T. Behnke; M. Doucet; N. Ghodbane; A. Imhof; C. Martinez; W. Zeuner
2001-08-22T23:59:59.000Z
The behavior of artificially grown CVD diamond films under intense electromagnetic radiation has been studied. The properties of irradiated diamond samples have been investigated using the method of thermally stimulated current and by studying their charge collection properties. Diamonds have been found to remain unaffected after doses of 6.8 MGy of 10 keV photons and 10 MGy of MeV-range photons. This observation makes diamond an attractive detector material for a calorimeter in the very forward region of the proposed TESLA detector.
Compression of laser radiation in plasmas via electromagnetic cascading
Kalmykov, Serguei; Shvets, Gennady [Department of Physics and Institute for Fusion Studies, University of Texas at Austin, One University Station C1500, Austin, Texas 78712 (United States)
2006-05-15T23:59:59.000Z
A train of few-laser-cycle relativistically intense radiation spikes with a terahertz repetition rate can be organized self-consistently in plasma from two frequency detuned co-propagating laser beams of low intensity. Large frequency bandwidth for the compression of spikes is produced via laser-induced periodic modulation of the plasma refractive index. The beat-wave-driven electron plasma wave downshifted from the plasma frequency creates a moving index grating thus inducing a periodic phase modulation of the driving laser (in spectral terms, electromagnetic cascading). The group velocity dispersion compresses the chirped laser beat notes to a few-cycle duration and relativistic intensity either concurrently in the same, or sequentially in different plasmas. Particle-in-cell simulations indicate that the effect persists in a realistic three-dimensional axisymmetric geometry.
Nonlinear Landau damping of transverse electromagnetic waves in dusty plasmas
Tsintsadze, N. L. [E. Andronikashvili Institute of Physics, Tbilisi 0171 (Georgia); Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Chaudhary, Rozina [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)
2009-04-15T23:59:59.000Z
High-frequency transverse electromagnetic waves in a collisionless isotropic dusty plasma damp via nonlinear Landau damping. Taking into account the latter we have obtained a generalized set of Zakharov equations with local and nonlocal terms. Then from this coupled set of Zakharov equations a kinetic nonlinear Schroedinger equation with local and nonlocal nonlinearities is derived for special cases. It is shown that the modulation of the amplitude of the electromagnetic waves leads to the modulation instability through the nonlinear Landau damping term. The maximum growth rate is obtained for the special case when the group velocity of electromagnetic waves is close to the dust acoustic velocity.
Electromagnetic Waves Propagation in 3D Plasma Configurations
Electromagnetic Waves Propagation in 3D Plasma Configurations Pavel Popovich, W. Anthony Cooper in a plasma strongly depends on the frequency, therefore the tools used for wave propagation studies are very that will allow for the calculation of the fields and energy deposition of a low-frequency wave propagating
"Millikan oil drops" as quantum transducers between electromagnetic and gravitational radiation
Raymond Y. Chiao
2007-02-25T23:59:59.000Z
Pairs of Planck-mass-scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. This would open up observations of the gravity-wave analog of the Cosmic Microwave Background from the extremely early Big Bang, and also communications directly through the interior of the Earth.
Compression of Laser Radiation in Plasmas Using Electromagnetic Cascading
Kalmykov, Serguei; Shvets, Gennady [Department of Physics and Institute for Fusion Studies, University of Texas at Austin, One University Station C1500, Austin, Texas 78712 (United States)
2005-06-17T23:59:59.000Z
Compressing high-power laser beams in plasmas via generation of a coherent cascade of electromagnetic sidebands is described. The technique requires two copropagating beams detuned by a near-resonant frequency {omega} < or approx. {omega}{sub p}. The ponderomotive force of the laser beat wave drives an electron plasma wave which modifies the refractive index of plasma so as to produce a periodic phase modulation of the laser field with the beat period {tau}{sub b}=2{pi}/{omega}. A train of chirped laser beat notes (each of duration {tau}{sub b}) is thus created. The group velocity dispersion of radiation in plasma can then compress each beat note to a few-laser-cycle duration. As a result, a train of sharp electromagnetic spikes separated in time by {tau}{sub b} is formed. Depending on the plasma and laser parameters, chirping and compression can be implemented either concurrently in the same plasma or sequentially in different plasmas.
Surface electromagnetic wave equations in a warm magnetized quantum plasma
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)
2014-07-15T23:59:59.000Z
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.
Radiative Reactions and Coherence Modeling in the High Altitude Electromagnetic Pulse
Charles N. Vittitoe; Mario Rabinowitz
2003-06-03T23:59:59.000Z
A high altitude nuclear electromagnetic pulse (EMP) with a peak field intensity of 5 x 10^4 V/m carries momentum that results in a retarding force on the average Compton electron (radiating coherently to produce the waveform) with magnitude near that of the geomagnetic force responsible for the coherent radiation. The retarding force results from a self field effect. The Compton electron interaction with the self generated magnetic field due to the other electrons accounts for the momentum density in the propagating wave; interaction with the self generated electric field accounts for the energy flux density in the propagating wave. Coherent addition of radiation is also quantitatively modeled.
Electromagnetic Radiation and Motion of Really Shaped Particle
Jozef Klacka
2001-08-13T23:59:59.000Z
Relativistically covariant form of equation of motion for real particle (neutral in charge) under the action of electromagnetic radiation is derived. Various formulations of the equation of motion in the proper frame of reference of the particle are used. Main attention is devoted to the reformulation of the equation of motion in the general frame of reference, e. g., in the frame of reference of the source of electromagnetic radiation. This is the crucial form of equation of motion in applying it to motion of particles (cosmic dust, asteroids, ...) in the Universe if electromagnetic radiation acts on the particles. General relativistic equation of motion is presented.
Behavior of Electric Current Subjected to ELF Electromagnetic Radiation
Fran De Aquino
2002-10-05T23:59:59.000Z
Gravitational effects produced by ELF electromagnetic radiation upon the electric current in a conductor are studied. An apparatus has been constructed to test the behavior of current subjected to ELF radiation. The experimental results are in agreement with theoretical predictions and show that ELF radiation can cause transitory interruptions in electric current conduction.
Norin, L.; Leyser, T. B.; Nordblad, E.; Thide, B.; McCarrick, M. [Swedish Institute of Space Physics, Uppsala (Sweden); BAE Systems Advanced Technologies, Washington, D.C. (United States)
2009-02-13T23:59:59.000Z
Experimental results of secondary electromagnetic radiation, stimulated by high-frequency radio waves irradiating the ionosphere, are reported. We have observed emission peaks, shifted in frequency up to a few tens of Hertz from radio waves transmitted at several megahertz. These emission peaks are by far the strongest spectral features of secondary radiation that have been reported. The emissions are attributed to stimulated Brillouin scattering, long predicted but hitherto never unambiguously identified in high-frequency ionospheric interaction experiments. The experiments were performed at the High-Frequency Active Auroral Research Program (HAARP), Alaska, USA.
Electromagnetic radiation and motion of arbitrarily shaped particle
Jozef Klacka
2001-07-06T23:59:59.000Z
Covariant form of equation of motion for arbitrarily shaped particle in the electromagnetic radiation field is presented. Equation of motion in the proper frame of the particle uses the radiation pressure cross section 3 $\\times$ 3 matrix. The obtained equation of motion is compared with known result.
Remote Sensing Ayman F. Habib Electro-Magnetic Radiation
Habib, Ayman
Remote Sensing Ayman F. Habib 1 Chapter 2 Electro-Magnetic Radiation #12;Remote Sensing Ayman F. Habib 2 Elements of Remote Sensing #12;Remote Sensing Ayman F. Habib 3 Chapter 2 Radiation: nature & source #12;Remote Sensing Ayman F. Habib 4 Chapter 2 Interaction with the atmosphere #12;Remote Sensing
Remote Sensing Ayman F. Habib Electro-Magnetic Radiation
Habib, Ayman
Remote Sensing Ayman F. Habib 1 Chapter 2 Electro-Magnetic Radiation Remote Sensing Ayman F. Habib 2 Elements of Remote Sensing #12;Remote Sensing Ayman F. Habib 3 Chapter 2 Radiation: nature & source Remote Sensing Ayman F. Habib 4 Chapter 2 Interaction with the atmosphere #12;Remote Sensing Ayman
Matter Wave Radiation Leading to Matter Teleportation
Yong-Yi Huang
2015-02-12T23:59:59.000Z
The concept of matter wave radiation is put forward, and its equation is established for the first time. The formalism solution shows that the probability density is a function of displacement and time. A free particle and a two-level system are reinvestigated considering the effect of matter wave radiation. Three feasible experimental designs, especially a modified Stern-Gerlach setup, are proposed to verify the existence of matter wave radiation. Matter wave radiation effect in relativity has been formulated in only a raw formulae, which offers another explanation of Lamb shift. A possible mechanics of matter teleportation is predicted due to the effect of matter wave radiation.
Electromagnetic and nuclear radiation detector using micromechanical sensors
Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN); Wachter, Eric A. (Oak Ridge, TN)
2000-01-01T23:59:59.000Z
Electromagnetic and nuclear radiation is detected by micromechanical sensors that can be coated with various interactive materials. As the micromechanical sensors absorb radiation, the sensors bend and/or undergo a shift in resonance characteristics. The bending and resonance changes are detected with high sensitivity by any of several detection methods including optical, capacitive, and piezoresistive methods. Wide bands of the electromagnetic spectrum can be imaged with picoJoule sensitivity, and specific absorptive coatings can be used for selective sensitivity in specific wavelength bands. Microcantilevers coated with optical cross-linking polymers are useful as integrating optical radiation dosimeters. Nuclear radiation dosimetry is possible by fabricating cantilevers from materials that are sensitive to various nuclear particles or radiation. Upon exposure to radiation, the cantilever bends due to stress and its resonance frequency shifts due to changes in elastic properties, based on cantilever shape and properties of the coating.
Gravitational Hertz experiment with electromagnetic radiation in a strong magnetic field
N. I. Kolosnitsyn; V. N. Rudenko
2015-04-24T23:59:59.000Z
Brief review of principal ideas in respect of the high frequency gravitational radiation generated and detected in the laboratory condition is presented. Interaction of electro-magnetic and gravitational waves into a strong magnetic field is considered as a more promising variant of the laboratory GW-Hertz experiment. The formulae of the direct and inverse Gertsenshtein-Zeldovich effect are derived. Numerical estimates are given and a discussion of a possibility of observation of these effects in a lab is carried out.
Surface wave chemical detector using optical radiation
Thundat, Thomas G.; Warmack, Robert J.
2007-07-17T23:59:59.000Z
A surface wave chemical detector comprising at least one surface wave substrate, each of said substrates having a surface wave and at least one measurable surface wave parameter; means for exposing said surface wave substrate to an unknown sample of at least one chemical to be analyzed, said substrate adsorbing said at least one chemical to be sensed if present in said sample; a source of radiation for radiating said surface wave substrate with different wavelengths of said radiation, said surface wave parameter being changed by said adsorbing; and means for recording signals representative of said surface wave parameter of each of said surface wave substrates responsive to said radiation of said different wavelengths, measurable changes of said parameter due to adsorbing said chemical defining a unique signature of a detected chemical.
Gradient instabilities of electromagnetic waves in Hall thruster plasma
Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)
2013-04-15T23:59:59.000Z
This paper presents a linear analysis of gradient plasma instabilities in Hall thrusters. The study obtains and analyzes the dispersion equation of high-frequency electromagnetic waves based on the two-fluid model of a cold plasma. The regions of parameters corresponding to unstable high frequency modes are determined and the dependence of the increments and intrinsic frequencies on plasma parameters is obtained. The obtained results agree with those of previously published studies.
Modulational instability of electromagnetic waves in a collisional quantum magnetoplasma
Niknam, A. R., E-mail: a-niknam@sbu.ac.ir [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of); Rastbood, E.; Bafandeh, F.; Khorashadizadeh, S. M., E-mail: smkhorashadi@birjand.ac.ir [Physics Department of Birjand University, Birjand (Iran, Islamic Republic of)
2014-04-15T23:59:59.000Z
The modulational instability of right-hand circularly polarized electromagnetic electron cyclotron (CPEM-EC) wave in a magnetized quantum plasma is studied taking into account the collisional effects. Employing quantum hydrodynamic and nonlinear Schrödinger equations, the dispersion relation of modulated CPEM-EC wave in a collisional plasma has been derived. It is found that this wave is unstable in such a plasma system and the growth rate of the associated instability depends on various parameters such as electron Fermi temperature, plasma number density, collision frequency, and modulation wavenumber. It is shown that while the increase of collision frequency leads to increase of the growth rate of instability, especially at large wavenumber limit, the increase of plasma number density results in more stable modulated CPEM-EC wave. It is also found that in contrast to collisionless plasma in which modulational instability is restricted to small wavenumbers, in collisional plasma, the interval of instability occurrence can be extended to a large domain.
Filling of a cavity with zero-point electromagnetic radiation
Jiri J. Mares; V. Spicka; J. Kristofik; P. Hubik
2003-11-11T23:59:59.000Z
In the present contribution we analyse a simple thought process at T = 0 in an idealized heat engine having partitions made of a material with an upper frequency cut-off and bathed in zero-point (ZP) electromagnetic radiation. As a result, a possible mechanism of filling real cavities with ZP radiation based on Doppler's effect has been suggested and corresponding entropy changes are discussed.
Radio Science, Volume ???, Number , Pages 110, Time Reversal of Electromagnetic Waves and
Paris 7 - Denis Diderot, Université
electromagnetic pulse at a central frequency of 2.45 GHz in a high-Q cavity. Another antenna records the stronglyRadio Science, Volume ???, Number , Pages 110, Time Reversal of Electromagnetic Waves demonstration of time-reversal focusing with electromagnetic waves in a SISO scheme. An antenna transmits a 1 µs
Einstein's coefficients and the wave-particle duality in the theory of thermal radiation
Fedor V. Prigara
2005-01-19T23:59:59.000Z
It is shown that the concept of elementary resonator in the theory of thermal radiation implies the indivisible connection between particles (photons) and electromagnetic waves. This wave-particle duality covers both the Wien and Rayleigh-Jeans regions of spectrum.
Radiative reactions and coherence modeling in the high-altitude electromagnetic pulse
Vittitoe, C.N.; Rabinowitz, M.
1988-03-15T23:59:59.000Z
A high-altitude nuclear electromagnetic pulse (EMP) with a peak field intensity of 5 x 10/sup 4/ V/m carries momentum that results in a retarding force on the average Compton electron (radiating coherently to produce the waveform) with magnitude near that of the geomagnetic force responsible for the coherent radiation. The retarding force results from a self-field effect. The Compton electron interaction with the self-generated magnetic field due to the other electrons accounts for the momentum density in the propagating wave; interaction with the self-generated electric field accounts for the energy-flux density in the propagating wave. Coherent addition of radiation is also quantitatively modeled.
Screening of electromagnetic field fluctuations by s--wave and d--wave superconductors
Rachele Fermani; Stefan Scheel
2010-01-04T23:59:59.000Z
We investigate theoretically the shielding of the electromagnetic field fluctuations by s-wave and d-wave superconductors within the framework of macroscopic quantum electrodynamics. The spin flip lifetime is evaluated above a niobium and a bismuth strontium calcium copper oxide (BSCCO) surface, and the screening effect is studied as a function of the thickness of the superconducting layer. Further, we study the different temperature dependence of the atomic spin relaxation above the two superconductors.
Superconductors as quantum transducers and antennas for gravitational and electromagnetic radiation
Raymond Y. Chiao
2002-07-29T23:59:59.000Z
Superconductors will be considered as macroscopic quantum gravitational antennas and transducers, which can directly convert upon reflection a beam of quadrupolar electromagnetic radiation into gravitational radiation, and vice versa, and thus serve as practical laboratory sources and receivers of microwave and other radio-frequency gravitational waves. An estimate of the transducer conversion efficiency on the order of unity comes out of the Ginzburg-Landau theory for an extreme type II, dissipationless superconductor with minimal coupling to weak gravitational and electromagnetic radiation fields, whose frequency is smaller than the BCS gap frequency, thus satisfying the quantum adiabatic theorem. The concept of ``the impedance of free space for gravitational plane waves'' is introduced, and leads to a natural impedance-matching process, in which the two kinds of radiation fields are impedance-matched to each other around a hundred coherence lengths beneath the surface of the superconductor. A simple, Hertz-like experiment has been performed to test these ideas, and preliminary results will be reported. (PACS nos.: 03.65.Ud, 04.30.Db, 04.30.Nk, 04.80.Nn, 74.60-w, 74.72.Bk)
Pion light-front wave function, parton distribution and the electromagnetic form factor
Thomas Gutsche; Valery E. Lyubovitskij; Ivan Schmidt; Alfredo Vega
2014-10-23T23:59:59.000Z
We derive a light-front wave function of the pion, which reproduces its valence parton distribution and a electromagnetic form factor consistent with data.
Structures, systems and methods for harvesting energy from electromagnetic radiation
Novack, Steven D. (Idaho Falls, ID); Kotter, Dale K. (Shelley, ID); Pinhero, Patrick J. (Columbia, MO)
2011-12-06T23:59:59.000Z
Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.
Energy harvesting devices for harvesting energy from terahertz electromagnetic radiation
Novack, Steven D.; Kotter, Dale K.; Pinhero, Patrick J.
2012-10-09T23:59:59.000Z
Methods, devices and systems for harvesting energy from electromagnetic radiation are provided including harvesting energy from electromagnetic radiation. In one embodiment, a device includes a substrate and one or more resonance elements disposed in or on the substrate. The resonance elements are configured to have a resonant frequency, for example, in at least one of the infrared, near-infrared and visible light spectra. A layer of conductive material may be disposed over a portion of the substrate to form a ground plane. An optical resonance gap or stand-off layer may be formed between the resonance elements and the ground plane. The optical resonance gap extends a distance between the resonance elements and the layer of conductive material approximately one-quarter wavelength of a wavelength of the at least one resonance element's resonant frequency. At least one energy transfer element may be associated with the at least one resonance element.
Ion acoustic wave generation by a standing electromagnetic field in a subcritical plasma
Boyer, Edmond
by the ponderomotive force [1] associated with a standing electromagnetic pulse. Be- cause of the nonlinear response of the plasma to the electromagnetic pulse, a zero frequency electron den- sity perturbation is created with a wave number twice the electromagnetic one. Then, after the pulse, the plasma relaxes towards
Efthimion, Philip C. (Bedminister, NJ); Helfritch, Dennis J. (Flemington, NJ)
1989-11-28T23:59:59.000Z
An apparatus and method for creating high temperature plasmas for enhanced chemical processing of gaseous fluids, toxic chemicals, and the like, at a wide range of pressures, especially at atmospheric and high pressures includes an electro-magnetic resonator cavity, preferably a reentrant cavity, and a wave guiding structure which connects an electro-magnetic source to the cavity. The cavity includes an intake port and an exhaust port, each having apertures in the conductive walls of the cavity sufficient for the intake of the gaseous fluids and for the discharge of the processed gaseous fluids. The apertures are sufficiently small to prevent the leakage of the electro-magnetic radiation from the cavity. Gaseous fluid flowing from the direction of the electro-magnetic source through the guiding wave structure and into the cavity acts on the plasma to push it away from the guiding wave structure and the electro-magnetic source. The gaseous fluid flow confines the high temperature plasma inside the cavity and allows complete chemical processing of the gaseous fluids at a wide range of pressures.
Particle dynamics and deviation effects in the field of a strong electromagnetic wave
Donato Bini; Andrea Geralico; Maria Haney; Antonello Ortolan
2014-08-23T23:59:59.000Z
Some strong field effects on test particle motion associated with the propagation of a plane electromagnetic wave in the exact theory of general relativity are investigated. Two different profiles of the associated radiation flux are considered in comparison, corresponding to either constant or oscillating electric and magnetic fields with respect to a natural family of observers. These are the most common situations to be experimentally explored, and have a well known counterpart in the flat spacetime limit. The resulting line elements are determined by a single metric function, which turns out to be expressed in terms of standard trigonometric functions in the case of a constant radiation flux, and in terms of special functions in the case of oscillating flux, leading to different features of test particle motion. The world line deviation between both uncharged and charged particles on different spacetime trajectories due to the combined effect of gravitational and electromagnetic forces is studied. The interaction of charged particles with the background radiation field is also discussed through a general relativistic description of the inverse Compton effect. Motion as well as deviation effects on particles endowed with spin are studied too. Special situations may occur in which the direction of the spin vector change during the interaction, leading to obsevables effects like spin-flip.
Nanofocusing of mid-infrared electromagnetic waves on graphene monolayer
Qiu, Weibin, E-mail: wbqiu@hqu.edu.cn, E-mail: wqiu@semi.ac.cn [College of Information Science and Engineering, National Huaqiao University, Xiamen 361021, Fujian (China); Institute of Semiconductors, Chinese Academy of Science, 100083 Beijing (China); Liu, Xianhe; Zhao, Jing; He, Shuhong; Ma, Yuhui; Wang, Jia-Xian [College of Information Science and Engineering, National Huaqiao University, Xiamen 361021, Fujian (China); Pan, Jiaoqing [Institute of Semiconductors, Chinese Academy of Science, 100083 Beijing (China)
2014-01-27T23:59:59.000Z
Nanofocusing of mid-infrared (MIR) electromagnetic waves on graphene monolayer with gradient chemical potential is investigated with numerical simulation. On an isolated freestanding monolayer graphene sheet with spatially varied chemical potential, the focusing spot sizes of frequencies between 44 THz and 56 THz can reach around 1.6?nm and the intensity enhancement factors are between 2178 and 654. For 56 THz infrared, a group velocity as slow as 5×10{sup ?5} times of the light speed in vacuum is obtained at the focusing point. When the graphene sheet is placed on top of an aluminum oxide substrate, the focusing spot size of 56 THz infrared reduces to 1.1?nm and the intensity enhancement factor is still as high as 220. This structure offers an approach for focusing light in the MIR regime beyond the diffraction limit without complicated device geometry engineering.
A. B. Balakin; Z. G. Murzakhanov; G. V. Kisun'ko
2005-11-10T23:59:59.000Z
We discuss a gravitationally induced nonlinearity in hierarchic systems. We consider the generation of extremely low-frequency radio waves with a frequency of the periodic gravitational radiation; the generation is due to an induced nonlinear self-action of electromagnetic radiation in the vicinity of the gravitational-radiation source. These radio waves are a fundamentally new type of response of an electrodynamic system to gravitational radiation. That is why we here use an unconventional term: radio-wave messengers of periodic gravitational radiation.
G. Taylor; P.C. Efthimion; B.P. LeBlanc; M.D. Carter; J.B. Caughman; J.B. Wilgen; J. Preinhaelter; R.W. Harvey; S.A. Sabbagh
2005-02-02T23:59:59.000Z
Efficient coupling of thermal electron Bernstein waves (EBW) to ordinary mode (Omode) electromagnetic radiation has been measured in plasmas heated by energetic neutral beams and high harmonic fast waves in the National Spherical Torus Experiment (NSTX) [M. Ono, S. Kaye, M. Peng, et al., Proceedings 17th IAEA Fusion Energy Conference (IAEA, Vienna, Austria, 1999), Vol.3, p. 1135]. The EBW to electromagnetic mode coupling efficiency was measured to be 0.8 {+-} 0.2, compared to a numerical EBW modeling prediction of 0.65. The observation of efficient EBW coupling to O-mode, in relatively good agreement with numerical modeling, is a necessary prerequisite for implementing a proposed high power EBW current drive system on NSTX.
T. P. Sotiriou; T. A. Apostolatos
2004-10-25T23:59:59.000Z
The geometry around a rotating massive body, which carries charge and electrical currents, could be described by its multipole moments (mass moments, mass-current moments, electric moments, and magnetic moments). When a small body is orbiting this massive body, it will move on geodesics, at least for a time interval that is short with respect to the characteristic time of the binary due to gravitational radiation. By monitoring the waves emitted by the small body we are actually tracing the geometry of the central object, and hence, in principle, we can infer all its multipole moments. This paper is a generalization of previous similar results by Ryan. The fact that the electromagnetic moments of spacetime can be measured demonstrates that one can obtain information about the electromagnetic field purely from gravitational wave analysis. Additionally, these measurements could be used as a test of the no-hair theorem for black holes.
Simple Waves in Ideal Radiation Hydrodynamics
Bryan M. Johnson
2008-11-24T23:59:59.000Z
In the dynamic diffusion limit of radiation hydrodynamics, advection dominates diffusion; the latter primarily affects small scales and has negligible impact on the large scale flow. The radiation can thus be accurately regarded as an ideal fluid, i.e., radiative diffusion can be neglected along with other forms of dissipation. This viewpoint is applied here to an analysis of simple waves in an ideal radiating fluid. It is shown that much of the hydrodynamic analysis carries over by simply replacing the material sound speed, pressure and index with the values appropriate for a radiating fluid. A complete analysis is performed for a centered rarefaction wave, and expressions are provided for the Riemann invariants and characteristic curves of the one-dimensional system of equations. The analytical solution is checked for consistency against a finite difference numerical integration, and the validity of neglecting the diffusion operator is demonstrated. An interesting physical result is that for a material component with a large number of internal degrees of freedom and an internal energy greater than that of the radiation, the sound speed increases as the fluid is rarefied. These solutions are an excellent test for radiation hydrodynamic codes operating in the dynamic diffusion regime. The general approach may be useful in the development of Godunov numerical schemes for radiation hydrodynamics.
Gillani, S. S. A.; Shah, H. A. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Tsintsadze, N. L. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan); Institute of Physics, Tbilisi 380077 (Georgia); Razzaq, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore 54000 (Pakistan)
2010-08-15T23:59:59.000Z
It is shown that the interaction of the superstrong laser radiation with an isotropic plasma leads to the generation of low frequency electromagnetic (EM) waves and in particular a quasistationary magnetic field. When the relativistic circularly polarized transverse EM wave propagates along z-axis, it creates a ponderomotive force, which affects the motion of particles along the direction of its propagation. On the other hand, motion of the particles across the direction of propagation is defined by the ponderomotive potential. The dispersion relation for the transverse EM wave using a special distribution function, which has an anisotropic form, is derived. The dispersion relation is subsequently investigated for a number of special cases. In general, it is shown that the growth rate of the EM wave strongly depends upon its intensity.
THE BIANCHI IDENTITIES, ELECTROMAGNETIC WAVES, AND CHARGE CONSERVATION IN THE P(4) THEORY OF
Norris, Larry K.
OF GRAVITATION AND ELECTROMAGNETISM J. H. Chilton and K. S. Hammon Department of Physics North Carolina State, namely the affine geometry of the P(4) = O(1, 3) R4 theory of gravitation and electromag- netism (Norris) theory one obtains a conservation law and a wave equation for the electromagnetic field that parallels
Numerical methods for electromagnetic wave propagation and scattering in complex media
Moss, Christopher D. Q. (Christopher Doniert Q.), 1973-
2004-01-01T23:59:59.000Z
Numerical methods are developed to study various applications in electromagnetic wave propagation and scattering. Analytical methods are used where possible to enhance the efficiency, accuracy, and applicability of the ...
Paris-Sud XI, UniversitÃ© de
Computer simulations for direct conversion of the HF electromagnetic wave into the upper hybrid emissions (SEE). A direct conversion process is proposed as an excitation mech- anism of the upper hybrid, 1996) The electrostatic waves at the UH resonance were assumed to be excited via ``direct conversion
On the spontaneous emission of electromagnetic radiation in the CSL model
Donadi, Sandro, E-mail: sandro.donadi@ts.infn.it [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy) [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste (Italy); Deckert, Dirk-André, E-mail: deckert@math.ucdavis.edu [Department of Mathematics, University of California, One Shields Ave, 95616 Davis (United States)] [Department of Mathematics, University of California, One Shields Ave, 95616 Davis (United States); Bassi, Angelo, E-mail: bassi@ts.infn.it [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy) [Department of Physics, University of Trieste, Strada Costiera 11, 34151 Trieste (Italy); Istituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste (Italy)
2014-01-15T23:59:59.000Z
Spontaneous photon emission in the Continuous Spontaneous Localization (CSL) model is studied one more time. In the CSL model each particle interacts with a noise field that induces the collapse of its wave function. As a consequence of this interaction, when the particle is electrically charged, it radiates. As discussed in Adler (2013) the formula for the emission rate, to first perturbative order, contains two terms: one is proportional to the Fourier component of the noise field at the same frequency as that of the emitted photon and one is proportional to the zero Fourier component of the noise field. As discussed in previous works, this second term seems unphysical. In Adler (2013) it was shown that the unphysical term disappears when the noise is confined to a bounded region and the final particle’s state is a wave packet. Here we investigate the origin of this unphysical term and why it vanishes according to the previous prescription. We will see that perturbation theory is formally not valid in the large time limit since the effect of the noise accumulates continuously in time. Therefore either one performs an exact calculation (or at least in some way includes higher order terms) as we do here, or one finds a way to make a perturbative calculation meaningful, e.g., by confining the system as in Adler (2013). -- Highlights: •We compute the electromagnetic radiation emission in collapse models. •Under only the dipole approximation, the equations of motion are solved exactly. •The electromagnetic interaction must be treated exactly. •In order to obtain the correct emission rate the particle must be bounded.
Electromagnetic wave propagation in an active medium and the equivalent SchrÃ¶dinger equation to provide an alternative, but equivalent, representation of plane electromagnetic em wave propagation it oscillates and then decreases exponentially. Thus, for large systems, the wave propagation is suppressed
Self-generation and management of spin-electromagnetic wave solitons and chaos
Ustinov, Alexey B.; Kondrashov, Alexandr V.; Nikitin, Andrey A.; Kalinikos, Boris A. [Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University, St. Petersburg 197376 (Russian Federation)
2014-06-09T23:59:59.000Z
Self-generation of microwave spin-electromagnetic wave envelope solitons and chaos has been observed and studied. For the investigation, we used a feedback active ring oscillator based on artificial multiferroic, which served as a nonlinear waveguide. We show that by increasing the wave amplification in the feedback ring circuit, a transition from monochromatic auto-generation to soliton train waveform and then to dynamical chaos occurs in accordance with the Ruelle-Takens scenario. Management of spin-electromagnetic-wave solitons and chaos parameters by both dielectric permittivity and magnetic permeability of the multiferroic waveguiding structure is demonstrated.
The electromagnetic fields and the radiation of a spatio-temporally varying electric current loop
Markus Lazar
2013-04-12T23:59:59.000Z
The electric and magnetic fields of a spatio-temporally varying electric current loop are calculated using the Jefimenko equations. The radiation and the nonradiation parts of the electromagnetic fields are derived in the framework of Maxwell's theory of electromagnetic fields. In this way, a new, exact, analytical solution of the Maxwell equation is found.
Chang-Hwan Lee; Ismail Zahed
2014-03-07T23:59:59.000Z
We discuss the general features of the electromagnetic radiation from a thermal hadronic gas as constrained by chiral symmetry. The medium effects on the electromagnetic spectral functions and the partial restoration of chiral symmetry are quantified in terms of the pion densities. The results are compared with the electromagnetic radiation from a strongly interacting quark-gluon plasma in terms of the leading gluon condensate operators. We use the spectral functions as constrained by the emission rates to estimate the electric conductivity, the light flavor susceptibility and diffusion constant across the transition from the correlated hadronic gas to a strongly interacting quark-gluon plasma.
Precipitation of radiation belt electrons by EMIC waves, observed from ground and space
Jordanova, Vania K [Los Alamos National Laboratory; Miyoski, Y [NAGOYA UNIV; Sakaguchi, K [NAGOYA UNIV; Shiokawa, K [NAGOYA UNIV; Evans, D S [NOAA, BOULDER; Albert, Jay [AFRL; Connors, M [UNIV OF ATHABASCA
2008-01-01T23:59:59.000Z
We show evidence that left-hand polarised electromagnetic ion cyclotron (EMIC) plasma waves can cause the loss of relativistic electrons into the atmosphere. Our unique set of ground and satellite observations shows coincident precipitation of ions with energies of tens of keY and of relativistic electrons into an isolated proton aurora. The coincident precipitation was produced by wave-particle interactions with EMIC waves near the plasmapause. The estimation of pitch angle diffusion coefficients supports that the observed EMIC waves caused coincident precipitation ofboth ions and relativistic electrons. This study clarifies that ions with energies of tens of ke V affect the evolution of relativistic electrons in the radiation belts via cyclotron resonance with EMIC waves, an effect that was first theoretically predicted in the early 1970's.
Weixing Shu; Zhongzhou Ren; Hailu Luo; Fei Li; Qin Wu
2006-10-11T23:59:59.000Z
Based on molecular optics we investigate the reflection and refraction of an electromagnetic wave between two semi-infinite anisotropic magnetoelectric materials. In terms of Hertz vectors and the principle of superposition, we generalize the extinction theorem and derive the propagation characteristics of wave. Using these results we can easily explain the physical origin of Brewster effect. Our results extend the extinction theorem to the propagation of wave between two arbitrary anisotropic materials and the methods used can be applied to other problems of wave propagation in materials, such as scattering of light.
Jozef Klacka
2002-01-07T23:59:59.000Z
Relativistically covariant form of equation of motion for real particle (body) under the action of electromagnetic radiation is derived. Equation of motion in the proper frame of the particle uses the radiation pressure cross section 3 $\\times$ 3 matrix. Obtained covariant equation of motion is compared with another covariant equation of motion which was presented more than one year ago.
Orbital elements for motion of real particle under the action of electromagnetic radiation
Jozef Klacka
2002-01-14T23:59:59.000Z
Discussion of different types of osculating orbital elements for motion of real dust particle under the action of electromagnetic radiation in the central gravitational field is presented. It is shown that physically correct access is based on gravitational acceleration as the only radial acceleration -- ``radiation pressure'' is not included in the radial acceleration.
Geometric Phase Of The Faraday Rotation Of Electromagnetic Waves In Magnetized Plasma
Jian Liu and Hong Qin
2011-11-07T23:59:59.000Z
The geometric phase of circularly polarized electromagnetic waves in nonuniform magnetized plasmas is studied theoretically. The variation of the propagation direction of circularly polarized waves results in a geometric phase, which also contributes to the Faraday rotation, in addition to the standard dynamical phase. The origin and properties of the geometric phase is investigated. The in uence of the geometric phase to plasma diagnostics using Faraday rotation is also discussed as an application of the theory.
Nikitin, Andrey A.; Ustinov, Alexey B. [Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University, St. Petersburg 197376 (Russian Federation); Department of Mathematics and Physics, Lappeenranta University of Technology, Lappeenranta 53850 Finland (Finland); Semenov, Alexander A.; Kalinikos, Boris A. [Department of Physical Electronics and Technology, St. Petersburg Electrotechnical University, St. Petersburg 197376 (Russian Federation); Lähderanta, E. [Department of Mathematics and Physics, Lappeenranta University of Technology, Lappeenranta 53850 Finland (Finland)
2014-03-03T23:59:59.000Z
Spin-electromagnetic waves propagating in thin-film multilayered multiferroic structures containing a slot transmission line have been investigated both experimentally and theoretically. The thin-film structure was composed of a ferrite film, a ferroelectric film, and a slot-line. It was shown that the spectrum of the spin-electromagnetic wave was formed as a result of hybridization of the spin wave in the ferrite film with the electromagnetic wave in the slot-line and was electrically and magnetically tunable. For the experimental investigations, a microwave phase shifter based on the multiferroic structure has been fabricated. Performance characteristics are presented.
Electromagnetic plane waves with negative phase velocity in charged black strings
Sharif, M., E-mail: msharif.math@pu.edu.pk; Manzoor, R., E-mail: rubabmanzoor9@yahoo.com [University of the Punjab, Department of Mathematics (Pakistan)
2013-02-15T23:59:59.000Z
We investigate the propagation regions of electromagnetic plane waves with negative phase velocity in the ergosphere of static charged black strings. For such a propagation, some conditions for negative phase velocity are established that depend on the metric components and the choice of the octant. We conclude that these conditions remain unaffected by the negative values of the cosmological constant.
Nonlinear interactions of electromagnetic waves with the auroral ionosphere
Wong, Alfred Y. [Department of Physics and Astronomy, UCLA, Los Angeles, California 90024 (United States)
1999-09-20T23:59:59.000Z
The ionosphere provides us with an opportunity to perform plasma experiments in an environment with long confinement times, very large-scale lengths, and no confining walls. The auroral ionosphere with its nearly vertical magnetic field geometry is uniquely endowed with large amount of free energy from electron and ion precipitation along the magnetic field and mega-ampere current across the magnetic field. To take advantage of this giant outdoor laboratory, two facilities HAARP and HIPAS, with frequencies ranging from the radio to optical bands, are now available for active probing of and interaction with this interesting region. The ponderomotive pressures from the self-consistent wave fields have produced significant local perturbations of density and particle distributions at heights where the incident EM frequency matches a plasma resonance. This paper will review theory and experiments covering the nonlinear phenomena of parametric decay instability to wave collapse processes. At HF frequencies plasma lenses can be created by preconditioning pulses to focus what is a normally divergent beam into a high-intensity spot to further enhance nonlinear phenomena. At optical wavelengths a large rotating liquid metal mirror is used to focus laser pulses up to a given height. Such laser pulses are tuned to the same wavelengths of selected atomic and molecular resonances, with resulting large scattering cross sections. Ongoing experiments on dual-site experiments and excitation of ELF waves will be presented. The connection of such basic studies to environmental applications will be discussed. Such applications include the global communication using ELF waves, the ozone depletion and remediation and the control of atmospheric CO{sub 2} through the use of ion cyclotron resonant heating.
Device for conversion of electromagnetic radiation into electrical current
Blakeslee, A.E.; Mitchell, K.W.
1980-03-25T23:59:59.000Z
Electromagnetic energy may be converted directly into electrical energy by a device comprising a sandwich of at least two semiconductor portions, each portion having a p-n junction with a characteristic energy gap, and the portions lattice matched to one another by an intervening superlattice structure. This superlattice acts to block propagation into the next deposited portion of those dislocation defects which can form due to lattice mismatch between adjacent portions.
Zheludev, Nikolay
Asymmetric Propagation of Electromagnetic Waves through a Planar Chiral Structure V. A. Fedotov,1 of the effect would be reversed for an electromag- netic wave propagating in opposite directions. It is a polarization sensitive transmission effect asymmetric with respect to the direc- tion of wave propagation
Investigation of Ultrafast Laser-Driven Radiative Blast Waves
Edwards, M. J.; MacKinnon, A. J.; Zweiback, J.; Shigemori, K.; Ryutov, D.; Rubenchik, A. M.; Keilty, K. A.; Liang, E.; Remington, B. A.; Ditmire, T.
2001-08-20T23:59:59.000Z
We have examined the evolution of cylindrically symmetric blast waves produced by the deposition of femtosecond laser pulses in gas jets. In high-Z gases radiative effects become important. We observe the production of an ionization precursor ahead of the shock front and deceleration parameters below the adiabatic value of 1/2 (for a cylinder), an effect expected when the blast wave loses energy by radiative cooling. Despite significant radiative cooling, the blast waves do not appear to develop thin shell instabilities expected for strongly radiative waves. This is believed to be due to the stabilizing effect of a relatively thick blast wave shell resulting in part from electron thermal conduction effects.
Propagation of electromagnetic waves in a structured ionosphere
Murphy, T.
1996-06-01T23:59:59.000Z
The ionosphere is a birefringent medium which strongly affects the transmission of very high frequency (vhf) radio signals. These effects must be understood in detail if one wishes to look at the propagation of wide bandwidth coherent signals through the ionosphere. We develop a general perturbative solution of Maxwell`s equations for vhf signals propagating in the ionosphere, subject only to mild restrictions on the ionospheric structure. This solution can be extended to give the propagating field to any desired degree of precision. The case of a laminar ionosphere with harmonic waves is developed in greater detail, and we show how to calculate the ray path in this case. This solution is used to elucidate the effects of refraction on the phase of the signal, and we calculate the spatial- and frequency-coherence functions. The electric field for a laminar ionosphere without waves is analyzed to clarify the physical origins of the terms modifying the signal phase. We then calculate the solution in this case for the Appleton-Hartree model of the ionospheric dielectric function and express the result as a series in inverse powers of frequency. We conclude by calculating the ray path for a model ionosphere using the Appleton-Hartree dielectric function and a parabolic layer for the electron density.
2D modeling of electromagnetic waves in cold plasmas
Crombé, K. [Laboratory for Plasma Physics, Association EURATOM - Belgian State Trilateral Euregio Cluster, Renaissancelaan 30 Avenue de la Renaissance, B-1000 Brussels, Belgium and Department of Applied Physics, Ghent University, Sint-Pietersnieuwstraat 41 B4, B (Belgium); Van Eester, D.; Koch, R.; Kyrytsya, V. [Laboratory for Plasma Physics, Association EURATOM - Belgian State Trilateral Euregio Cluster, Renaissancelaan 30 Avenue de la Renaissance, B-1000 Brussels (Belgium)
2014-02-12T23:59:59.000Z
The consequences of sheath (rectified) electric fields, resulting from the different mobility of electrons and ions as a response to radio frequency (RF) fields, are a concern for RF antenna design as it can cause damage to antenna parts, limiters and other in-vessel components. As a first step to a more complete description, the usual cold plasma dielectric description has been adopted, and the density profile was assumed to be known as input. Ultimately, the relevant equations describing the wave-particle interaction both on the fast and slow timescale will need to be tackled but prior to doing so was felt as a necessity to get a feeling of the wave dynamics involved. Maxwell's equations are solved for a cold plasma in a 2D antenna box with strongly varying density profiles crossing also lower hybrid and ion-ion hybrid resonance layers. Numerical modelling quickly becomes demanding on computer power, since a fine grid spacing is required to capture the small wavelengths effects of strongly evanescent modes.
Shear driven electromagnetic drift-waves in a nonuniform dense magnetoplasma
Tariq, Sabeen; Mirza, Arshad M. [Theoretical Plasma Physics Group, Department of Physics, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Masood, Waqas [Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad 44000 (Pakistan); National Center for Physics (NCP), Islamabad 44000 (Pakistan)
2011-08-15T23:59:59.000Z
Linear characteristic properties of high- and low-frequency (in comparison with the cyclotron frequency) electromagnetic drift-waves are studied in a nonuniform, dense magnetoplasma (composed of electrons and ions), in the presence of parallel (magnetic field-aligned) velocity shear, by using quantum magnetohydrodynamic model. By applying the drift-approximation (viz., |{partial_derivative} {sub t}|<<{omega}{sub ci}<<{omega}{sub ce}) to the quantum momentum equations, together with the continuity equations and the Poisson equation, we derive the governing equations for electromagnetic drift-waves with the shear flow. These linear equations are then Fourier transformed to obtain the dispersion relation in both high-frequency and low-frequency regimes. The dispersion relations are then discussed under various limiting cases.
The CMS Electromagnetic Calorimeter Group; P. Adzic; N. Almeida; D. Andelin; I. Anicin; Z. Antunovic; R. Arcidiacono; M. W. Arenton; E. Auffray; S. Argiro; A. Askew; S. Baccaro; S. Baffioni; M. Balazs; D. Bandurin; D. Barney; L. M. Barone; A. Bartoloni; C. Baty; S. Beauceron; K. W. Bell; C. Bernet; M. Besancon; B. Betev; R. Beuselinck; C. Biino; J. Blaha; P. Bloch; A. Borisevitch; A. Bornheim; J. Bourotte; R. M. Brown; M. Buehler; P. Busson; B. Camanzi; T. Camporesi; N. Cartiglia; F. Cavallari; A. Cecilia; P. Chang; Y. H. Chang; C. Charlot; E. A. Chen; W. T. Chen; Z. Chen; R. Chipaux; B. C. Choudhary; R. K. Choudhury; D. J. A. Cockerill; S. Conetti; S. Cooper; F. Cossutti; B. Cox; D. G. Cussans; I. Dafinei; D. R. Da Silva Di Calafiori; G. Daskalakis; A. David; K. Deiters; M. Dejardin; A. De Benedetti; G. Della Ricca; D. Del Re; D. Denegri; P. Depasse; J. Descamps; M. Diemoz; E. Di Marco; G. Dissertori; M. Dittmar; L. Djambazov; M. Djordjevic; L. Dobrzynski; A. Dolgopolov; S. Drndarevic; G. Drobychev; D. Dutta; M. Dzelalija; A. Elliott-Peisert; H. El Mamouni; I. Evangelou; B. Fabbro; J. L. Faure; J. Fay; A. Fedorov; F. Ferri; D. Franci; G. Franzoni; K. Freudenreich; W. Funk; S. Ganjour; S. Gascon; M. Gataullin; F. X. Gentit; A. Ghezzi; A. Givernaud; S. Gninenko; A. Go; B. Gobbo; N. Godinovic; N. Golubev; P. Govoni; N. Grant; P. Gras; M. Haguenauer; G. Hamel de Monchenault; M. Hansen; J. Haupt; H. F. Heath; B. Heltsley; W. Hintz; R. Hirosky; P. R. Hobson; A. Honma; G. W. S. Hou; Y. Hsiung; M. Huhtinen; B. Ille; Q. Ingram; A. Inyakin; P. Jarry; C. Jessop; D. Jovanovic; K. Kaadze; V. Kachanov; S. Kailas; S. K. Kataria; B. W. Kennedy; P. Kokkas; T. Kolberg; M. Korjik; N. Krasnikov; D. Krpic; Y. Kubota; C. M. Kuo; P. Kyberd; A. Kyriakis; M. Lebeau; P. Lecomte; P. Lecoq; A. Ledovskoy; M. Lethuillier; S. W. Lin; W. Lin; V. Litvine; E. Locci; E. Longo; D. Loukas; P. D. Luckey; W. Lustermann; Y. Ma; M. Malberti; J. Malclès; D. Maletic; N. Manthos; Y. Maravin; C. Marchica; N. Marinelli; A. Markou; C. Markou; M. Marone; V. Matveev; C. Mavrommatis; P. Meridiani; P. Milenovic; P. Miné; O. Missevitch; A. K. Mohanty; F. Moortgat; P. Musella; Y. Musienko; A. Nardulli; J. Nash; P. Nedelec; P. Negri; H. B. Newman; A. Nikitenko; F. Nessi-Tedaldi; M. M. Obertino; G. Organtini; T. Orimoto; M. Paganoni; P. Paganini; A. Palma; L. Pant; A. Papadakis; I. Papadakis; I. Papadopoulos; R. Paramatti; P. Parracho; N. Pastrone; J. R. Patterson; F. Pauss; J-P. Peigneux; E. Petrakou; D. G. Phillips II; P. Piroué; F. Ptochos; I. Puljak; A. Pullia; T. Punz; J. Puzovic; S. Ragazzi; S. Rahatlou; J. Rander; P. A. Razis; N. Redaelli; D. Renker; S. Reucroft; P. Ribeiro; C. Rogan; M. Ronquest; A. Rosowsky; C. Rovelli; P. Rumerio; R. Rusack; S. V. Rusakov; M. J. Ryan; L. Sala; R. Salerno; M. Schneegans; C. Seez; P. Sharp; C. H. Shepherd-Themistocleous; J. G. Shiu; R. K. Shivpuri; P. Shukla; C. Siamitros; D. Sillou; J. Silva; P. Silva; A. Singovsky; Y. Sirois; A. Sirunyan; V. J. Smith; F. Stöckli; J. Swain; T. Tabarelli de Fatis; M. Takahashi; V. Tancini; O. Teller; K. Theofilatos; C. Thiebaux; V. Timciuc; C. Timlin; M. Titov; A. Topkar; F. A. Triantis; S. Troshin; N. Tyurin; K. Ueno; A. Uzunian; J. Varela; P. Verrecchia; J. Veverka; T. Virdee; M. Wang; D. Wardrope; M. Weber; J. Weng; J. H. Williams; Y. Yang; I. Yaselli; R. Yohay; A. Zabi; S. Zelepoukine; J. Zhang; L. Y. Zhang; K. Zhu; R. Y. Zhu
2009-12-22T23:59:59.000Z
Ensuring the radiation hardness of PbWO4 crystals was one of the main priorities during the construction of the electromagnetic calorimeter of the CMS experiment at CERN. The production on an industrial scale of radiation hard crystals and their certification over a period of several years represented a difficult challenge both for CMS and for the crystal suppliers. The present article reviews the related scientific and technological problems encountered.
Multipole radiation in a collisonless gas coupled to electromagnetism or scalar gravitation
Sebastian Bauer; Markus Kunze; Gerhard Rein; Alan D. Rendall
2005-08-29T23:59:59.000Z
We consider the relativistic Vlasov-Maxwell and Vlasov-Nordstr\\"om systems which describe large particle ensembles interacting by either electromagnetic fields or a relativistic scalar gravity model. For both systems we derive a radiation formula analogous to the Einstein quadrupole formula in general relativity.
ElectroMagnetic Radiations of FPGAs: High Spatial Resolution Cartography and Attack of a
Boyer, Edmond
ElectroMagnetic Radiations of FPGAs: High Spatial Resolution Cartography and Attack, a "root of trust" must be defined, insulated and then carefully protected. Until very recently, this role agencies) have tackled the issue of protecting ASICs from side-channel attacks (SCAs). In the meantime
M. Marklund; P. K. Shukla; G. Brodin; L. Stenflo
2004-10-21T23:59:59.000Z
The nonlinear interaction, due to quantum electrodynamical (QED) effects, between two electromagnetic pulses and a radiation gas is investigated. It is found that the governing equations admit both modulational and filamentational instabilities. The instability growth rates are derived, and the results are discussed.
Electromagnetic wave propagation with negative phase velocity in regular black holes
Sharif, M., E-mail: msharif.math@pu.edu.pk; Manzoor, R., E-mail: rubabmanzoor9@yahoo.com [University of the Punjab, Department of Mathematics (Pakistan)
2012-12-15T23:59:59.000Z
We discuss the propagation of electromagnetic plane waves with negative phase velocity in regular black holes. For this purpose, we consider the Bardeen model as a nonlinear magnetic monopole and the Bardeen model coupled to nonlinear electrodynamics with a cosmological constant. It turns out that the region outside the event horizon of each regular black hole does not support negative phase velocity propagation, while its possibility in the region inside the event horizon is discussed.
Kuzmin, Dmitry A; Shavrov, Vladimir G
2014-01-01T23:59:59.000Z
Electrodynamic properties of the graphene - magnetic semiconductor - graphene superlattice placed in magnetic field have been investigated theoretically in Faraday geometry with taking into account dissipation processes. Frequency and field dependences of the reflectance, transmittance and absorbtance of electromagnetic waves by such superlattice have been calculated for different numbers of periods of the structure and different sizes of the periods with using a transfer matrix method. The possibility of efficient control of electrodynamic properties of graphene - magnetic semiconductor - graphene superlattice has been shown.
Advances in non-planar electromagnetic prototyping
Ehrenberg, Isaac M
2013-01-01T23:59:59.000Z
The advent of metamaterials has introduced new ways to manipulate how electromagnetic waves reflect, refract and radiate in systems where the range of available material properties now includes negative permittivity, ...
Speech coding, reconstruction and recognition using acoustics and electromagnetic waves
Holzrichter, J.F.; Ng, L.C.
1998-03-17T23:59:59.000Z
The use of EM radiation in conjunction with simultaneously recorded acoustic speech information enables a complete mathematical coding of acoustic speech. The methods include the forming of a feature vector for each pitch period of voiced speech and the forming of feature vectors for each time frame of unvoiced, as well as for combined voiced and unvoiced speech. The methods include how to deconvolve the speech excitation function from the acoustic speech output to describe the transfer function each time frame. The formation of feature vectors defining all acoustic speech units over well defined time frames can be used for purposes of speech coding, speech compression, speaker identification, language-of-speech identification, speech recognition, speech synthesis, speech translation, speech telephony, and speech teaching. 35 figs.
Karsilayan, Nur
2011-08-08T23:59:59.000Z
FULL-WAVE SURFACE INTEGRAL EQUATION METHOD FOR ELECTROMAGNETIC-CIRCUIT SIMULATION OF THREE-DIMENSIONAL INTERCONNECTS IN LAYERED MEDIA A Dissertation by NUR KURT KARSILAYAN Submitted to the Office of Graduate Studies of Texas A&M University... in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY May 2010 Major Subject: Electrical Engineering FULL-WAVE SURFACE INTEGRAL EQUATION METHOD FOR ELECTROMAGNETIC-CIRCUIT SIMULATION OF THREE-DIMENSIONAL INTERCONNECTS...
Hammond, R.T. [Physics Department, North Dakota State University, Fargo, North Dakota 58105 (United States)] [Physics Department, North Dakota State University, Fargo, North Dakota 58105 (United States); Davis, J.; Bobb, L. [Naval Air Warfare Center, Code 4556, Mail Stop 2, Patuxent River, Maryland 20670 (United States)] [Naval Air Warfare Center, Code 4556, Mail Stop 2, Patuxent River, Maryland 20670 (United States)
1997-02-01T23:59:59.000Z
The reflection, transmission, and absorption coefficients are derived for long-wavelength electromagnetic radiation propagating through a medium that exhibits a Gaussian conductivity. It is shown that, under certain circumstances, this applies to the ionosphere. The effects of different peak conductivities and Gaussian widths are examined, and a useful form for calculating transmission and reflection coefficients is presented. {copyright} {ital 1997 American Institute of Physics.}
Electromagnetic radiation from a plasma slab during the development of Weibel instability
Vagin, K. Yu.; Romanov, A. Yu.; Uryupin, S. A. [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)
2012-01-15T23:59:59.000Z
Electromagnetic radiation from an anisotropic plasma slab formed by ionization of matter in the field of a high-power femtosecond pulse is studied. It is shown that the growth of initial field perturbations in the course of Weibel instability is accompanied by the generation of nonmonochromatic radiation with a characteristic frequency on the order of the instability growth rate. It is found that perturbations with characteristic scale lengths less than or on the order of the ratio of the speed of light to the Langmuir frequency are excited and radiated most efficiently, provided that the slab is thicker than this ratio.
LFS-3 - new radiation hard scintillator for electromagnetic calorimeters
Kozlov, V A; Zavartsev, Yu D; Zavertyaev, M V; Zerrouk, A F
2009-01-01T23:59:59.000Z
Radiation damage of new heavy LFS-3 scintillating crystals has been studied using powerful $^{60}Co$ source at the dose rate of 4 Krad/min. No deterioration in optical transmission of LFS-3 crystals was observed after irradiation with the dose of 23 Mrad.
Bell, Zane W. (Oak Ridge, TN)
2000-01-01T23:59:59.000Z
A sensor for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising: a sensor for the detection of gamma radiation, the sensor defining a sensing head; the sensor further defining an output end in communication with the sensing head; and an exterior neutron-sensitive material configured to form around the sensing head; wherein the neutron-sensitive material, subsequent to the capture of the neutron, fissions into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the first excited state decaying via the emission of a single gamma ray at 478 keV which can in turn be detected by the sensing head; and wherein the sensing head can also detect the ionizing electromagnetic radiation from an incident radiation field without significant interference from the neutron-sensitive material. A method for simultaneously detecting neutrons and ionizing electromagnetic radiation comprising the steps of: providing a gamma ray sensitive detector comprising a sensing head and an output end; conforming an exterior neutron-sensitive material configured to form around the sensing head of the detector; capturing neutrons by the sensing head causing the neutron-sensitive material to fission into an alpha-particle and a .sup.7 Li ion that is in a first excited state in a majority of the fissions, the state decaying via the emission of a single gamma ray at 478 keV; sensing gamma rays entering the detector through the neutron-sensitive material; and producing an output through a readout device coupled to the output end; wherein the detector provides an output which is proportional to the energy of the absorbed ionizing electromagnetic radiation.
Optical waves in crystal propagation and control of laser radiation
Yariv, A.; Yeh, P.
1983-01-01T23:59:59.000Z
As a text for a course in electro-optics for electrical engineering and applied physics students, it presents the propagation of laser radiation in various optical media and instructs in the analysis and design of electro-optical devices. The content of the book presupposes an introduction to Maxwell's equations in an intermediate course in electricity and magnetism as well as some mathematical background in Fourier integrals, matrix algebra, and differential equations. Contents, abridged: Electromagnetic fields. Propagation of laser beams. Jones calculus and its application to birefringent optical systems. Electromagnetic propagation in periodic media. Electro-optic devices. Acousto-optics. Indexes.
Electromagnetic Wave Propagation in Two-Dimensional Photonic Crystals
Stavroula Foteinopoulou
2003-12-12T23:59:59.000Z
In this dissertation, they have undertaken the challenge to understand the unusual propagation properties of the photonic crystal (PC). The photonic crystal is a medium where the dielectric function is periodically modulated. These types of structures are characterized by bands and gaps. In other words, they are characterized by frequency regions where propagation is prohibited (gaps) and regions where propagation is allowed (bands). In this study they focus on two-dimensional photonic crystals, i.e., structures with periodic dielectric patterns on a plane and translational symmetry in the perpendicular direction. They start by studying a two-dimensional photonic crystal system for frequencies inside the band gap. The inclusion of a line defect introduces allowed states in the otherwise prohibited frequency spectrum. The dependence of the defect resonance state on different parameters such as size of the structure, profile of incoming source, etc., is investigated in detail. For this study, they used two popular computational methods in photonic crystal research, the Finite Difference Time Domain method (FDTD) and the Transfer Matrix Method (TMM). The results for the one-dimensional defect system are analyzed, and the two methods, FDTD and TMM, are compared. Then, they shift their attention only to periodic two-dimensional crystals, concentrate on their band properties, and study their unusual refractive behavior. Anomalous refractive phenomena in photonic crystals included cases where the beam refracts on the ''wrong'' side of the surface normal. The latter phenomenon, is known as negative refraction and was previously observed in materials where the wave vector, the electric field, and the magnetic field form a left-handed set of vectors. These materials are generally called left-handed materials (LHM) or negative index materials (NIM). They investigated the possibility that the photonic crystal behaves as a LHM, and how this behavior relates with the observed negatively refractive phenomena. They found that in the PC system, negative refraction is neither a prerequisite nor guarantees left-handed behavior. They examined carefully the condition to obtain left-handed behavior in the PC. They proposed a wedge type of experiment, in accordance with the experiment performed on the traditional LHM, to test these conditions. They found that for certain frequencies the PC shows left-handed behavior and acts in some respects like a homogeneous medium with a negative refractive index. they used the realistic PC system for this case to show how negative refraction occurs at the interface between a material with a positive and a material with a negative refractive index. Their findings indicate that the formation of the negatively refracted beam is not instantaneous and involves a transient time. With this time-dependent analysis, they were able to address previous controversial issues about negative refraction concerning causality and the speed of light limit. Finally, they attempt a systematic study of anomalous refractive phenomena that can occur at the air-PC interface. They observe cases where only a single refracted beam (in the positive or negative direction) is present, as well as cases with birefringence. they classify these different effects according to their origin and type of propagation (left-handed or not). For a complete study of the system, they also obtain expressions for the energy and group velocities, and show their equality. For cases with very low index contrast, band folding becomes an artificiality. They discuss the validity of their findings when they move to the limit of photonic crystals with a low index modulation.
Gravitational Radiation from Travelling Waves on D-Strings
Julie D. Blum
2003-08-21T23:59:59.000Z
Boundary states that preserve supersymmetry are constructed for fractional D-strings with travelling waves on a ${\\bf C}^3/ {{\\bf Z}_2\\times {\\bf Z}_2}$ orbifold. The gravitational radiation emitted between two D-strings with antiparallel travelling waves is calculated.
Apparatuses and method for converting electromagnetic radiation to direct current
Kotter, Dale K; Novack, Steven D
2014-09-30T23:59:59.000Z
An energy conversion device may include a first antenna and a second antenna configured to generate an AC current responsive to incident radiation, at least one stripline, and a rectifier coupled with the at least one stripline along a length of the at least one stripline. An energy conversion device may also include an array of nanoantennas configured to generate an AC current in response to receiving incident radiation. Each nanoantenna of the array includes a pair of resonant elements, and a shared rectifier operably coupled to the pair of resonant elements, the shared rectifier configured to convert the AC current to a DC current. The energy conversion device may further include a bus structure operably coupled with the array of nanoantennas and configured to receive the DC current from the array of nanoantennas and transmit the DC current away from the array of nanoantennas.
Khorashadizadeh, S. M.; Rastbood, E.; Zeinaddini Meymand, H. [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of)] [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of); Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)] [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)
2013-08-15T23:59:59.000Z
The nonlinear coupling between circularly polarized electromagnetic (CPEM) waves and acoustic-like waves in a magnetoactive electron-positron-ion (e-p-i) plasma is studied, taking into account the relativistic motion of electrons and positrons. The possibility of modulational instability and its growth rate as well as the envelope soliton formation and its characteristics in such plasmas are investigated. It is found that the growth rate of modulation instability increases in the case that ?{sub c}/?<1 (?{sub c} and ? are the electron gyrofrequency and the CPEM wave frequency, respectively) and decreases in the case that ?{sub c}/?>1. It is also shown that in a magnetoactive e-p-i plasma, the width of bright soliton increases/decreases in case of (?{sub c}/?)<1/(?{sub c}/?)>1 by increasing the magnetic field strength.
Crawling Waves from Radiation Force Excitation ZAEGYOO HAH,1
Parker, Kevin J.
Crawling Waves from Radiation Force Excitation ZAEGYOO HAH,1 CHRISTOPHER HAZARD,2 YOUNG THUNG CHO1 from focused beams that produce radiation force excitation within the tissue. Some examples are also radiofrequency ablated hepatic lesions in vitro 6,7 to characterize human skeletal muscle in vivo 8, 9
Mork, B; Nelson, R; Kirkendall, B; Stenvig, N
2009-11-30T23:59:59.000Z
Application of BPL technologies to existing overhead high-voltage power lines would benefit greatly from improved simulation tools capable of predicting performance - such as the electromagnetic fields radiated from such lines. Existing EMTP-based frequency-dependent line models are attractive since their parameters are derived from physical design dimensions which are easily obtained. However, to calculate the radiated electromagnetic fields, detailed current distributions need to be determined. This paper presents a method of using EMTP line models to determine the current distribution on the lines, as well as a technique for using these current distributions to determine the radiated electromagnetic fields.
Zhou, Zhennan, E-mail: zhou@math.wisc.edu
2014-09-01T23:59:59.000Z
In this paper, we approximate the semi-classical Schrödinger equation in the presence of electromagnetic field by the Hagedorn wave packets approach. By operator splitting, the Hamiltonian is divided into the modified part and the residual part. The modified Hamiltonian, which is the main new idea of this paper, is chosen by the fact that Hagedorn wave packets are localized both in space and momentum so that a crucial correction term is added to the truncated Hamiltonian, and is treated by evolving the parameters associated with the Hagedorn wave packets. The residual part is treated by a Galerkin approximation. We prove that, with the modified Hamiltonian only, the Hagedorn wave packets dynamics give the asymptotic solution with error O(?{sup 1/2}), where ? is the scaled Planck constant. We also prove that, the Galerkin approximation for the residual Hamiltonian can reduce the approximation error to O(?{sup k/2}), where k depends on the number of Hagedorn wave packets added to the dynamics. This approach is easy to implement, and can be naturally extended to the multidimensional cases. Unlike the high order Gaussian beam method, in which the non-constant cut-off function is necessary and some extra error is introduced, the Hagedorn wave packets approach gives a practical way to improve accuracy even when ? is not very small.
Modeling the comfort effects of short-wave solar radiation indoors
Arens, Edward; Huang, Li; Hoyt, Tyler; Zhou, Xin; Schiavon, Stefano
2014-01-01T23:59:59.000Z
effects of short-wave solar radiation indoors. Building andEFFECTS OF SHORT-WAVE SOLAR RADIATION INDOORS Edward ARENSK. The effects of solar radiation on thermal comfort.
Electromagnetic radiation from nuclear collisions at RHIC energies
Simon Turbide; Charles Gale; Evan Frodermann; Ulrich Heinz
2007-12-20T23:59:59.000Z
The hot and dense strongly interacting matter created in collisions of heavy nuclei at RHIC energies is modeled with relativistic hydrodynamics, and the spectra of real and virtual photons produced at mid-rapidity in these events are calculated. Several different sources are considered, and their relative importance is compared. Specifically, we include jet fragmentation, jet-plasma interactions, the emission of radiation from the thermal medium and from primordial hard collisions. Our calculations consistently take into account jet energy loss, as evaluated in the AMY formalism. We obtain results for the spectra, the nuclear modification factor (R_AA), and the azimuthal anisotropy (v_2) that agree with the photon measurements performed by the PHENIX collaboration at RHIC.
Datskos, Panagiotis G. (Knoxville, TN); Rajic, Slobodan (Knoxville, TN); Datskou, Irene C. (Knoxville, TN); Egert, Charles M. (Oak Ridge, TN)
2002-01-01T23:59:59.000Z
A micromechanical sensor and method for detecting electromagnetic radiation involve producing photoelectrons from a metal surface in contact with a semiconductor. The photoelectrons are extracted into the semiconductor, which causes photo-induced bending. The resulting bending is measured, and a signal corresponding to the measured bending is generated and processed. A plurality of individual micromechanical sensors can be arranged in a two-dimensional matrix for imaging applications.
Xi Yanbin; Liu Yue [MOE Key Laboratory of Materials Modification by Laser, Electron, and Ion Beams, School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
2012-07-15T23:59:59.000Z
Considering different typical electron density profiles, a multi slab approximation model is built up to study the power absorption of broadband (0.75-30 GHz) electromagnetic waves in a partially ionized nonuniform magnetized plasma layer. Based on the model, the power absorption spectra for six cases are numerically calculated and analyzed. It is shown that the absorption strongly depends on the electron density fluctuant profile, the background electron number density, and the collision frequency. A potential optimum profile is also analyzed and studied with some particular parameters.
Litzenberg, Dale W.; Gallagher, Ian; Masi, Kathryn J.; Lee, Choonik; Prisciandaro, Joann I.; Hamstra, Daniel A.; Ritter, Timothy; Lam, Kwok L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-5010 (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan 48109-5010 (United States)
2013-08-15T23:59:59.000Z
Purpose: To present and characterize a measurement technique to quantify the calibration accuracy of an electromagnetic tracking system to radiation isocenter.Methods: This technique was developed as a quality assurance method for electromagnetic tracking systems used in a multi-institutional clinical hypofractionated prostate study. In this technique, the electromagnetic tracking system is calibrated to isocenter with the manufacturers recommended technique, using laser-based alignment. A test patient is created with a transponder at isocenter whose position is measured electromagnetically. Four portal images of the transponder are taken with collimator rotations of 45° 135°, 225°, and 315°, at each of four gantry angles (0°, 90°, 180°, 270°) using a 3 × 6 cm{sup 2} radiation field. In each image, the center of the copper-wrapped iron core of the transponder is determined. All measurements are made relative to this transponder position to remove gantry and imager sag effects. For each of the 16 images, the 50% collimation edges are identified and used to find a ray representing the rotational axis of each collimation edge. The 16 collimator rotation rays from four gantry angles pass through and bound the radiation isocenter volume. The center of the bounded region, relative to the transponder, is calculated and then transformed to tracking system coordinates using the transponder position, allowing the tracking system's calibration offset from radiation isocenter to be found. All image analysis and calculations are automated with inhouse software for user-independent accuracy. Three different tracking systems at two different sites were evaluated for this study.Results: The magnitude of the calibration offset was always less than the manufacturer's stated accuracy of 0.2 cm using their standard clinical calibration procedure, and ranged from 0.014 to 0.175 cm. On three systems in clinical use, the magnitude of the offset was found to be 0.053 ± 0.036, 0.121 ± 0.023, and 0.093 ± 0.013 cm.Conclusions: The method presented here provides an independent technique to verify the calibration of an electromagnetic tracking system to radiation isocenter. The calibration accuracy of the system was better than the 0.2 cm accuracy stated by the manufacturer. However, it should not be assumed to be zero, especially for stereotactic radiation therapy treatments where planning target volume margins are very small.
Vagin, K. Yu.; Uryupin, S. A., E-mail: uryupin@sci.lebedev.r [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)
2010-10-15T23:59:59.000Z
The reflection of an electromagnetic pulse by a nonequilibrium plasma in which the development of Weibel instability is possible has been studied. An exponentially strong amplification of the reflected signal at the stage of instability development has been found to be possible. The amplification maximum takes place at a radiation frequency comparable to the instability growth rate. A nonequilibrium plasma is shown to be a generator of radiation even after the switch-off of the incident pulse. The described effect of amplification of the reflected signal points, in particular, to a new possibility in mastering the terahertz frequency band.
Lezhnin, K V; Beskin, V S; Kando, M; Esirkepov, T Zh; Bulanov, S V
2014-01-01T23:59:59.000Z
In the ion acceleration by radiation pressure a transverse inhomogeneity of the electromagnetic pulse results in the displacement of the irradiated target in the off-axis direction limiting achievable ion energy. This effect is described analytically within the framework of the thin foil target model and with the particle-in-cell simulations showing that the maximum energy of accelerated ions decreases while the displacement from the axis of the target initial position increases. The results obtained can be applied for optimization of the ion acceleration by the laser radiation pressure with the mass limited targets.
Development and performance evaluation of an electromagnetic-type shock wave generator for lipolysis
Liang, S. M., E-mail: liangsm@cc.feu.edu.tw; Yang, Z. Y. [Department of Industrial Design, Far East University, No. 49, Zhonghua Road, Xinshi District, Tainan City 744, Taiwan (China)] [Department of Industrial Design, Far East University, No. 49, Zhonghua Road, Xinshi District, Tainan City 744, Taiwan (China); Chang, M. H. [Department of Aeronautics and Astronautics, National Cheng Kung University, No. 1, University Road, East District, Tainan City 701, Taiwan (China)] [Department of Aeronautics and Astronautics, National Cheng Kung University, No. 1, University Road, East District, Tainan City 701, Taiwan (China)
2014-01-15T23:59:59.000Z
This study aims at the design and development of electromagnetic-type intermittent shock wave generation in a liquid. The shock wave generated is focused at a focal point through an acoustic lens. This hardware device mainly consists of a full-wave bridge rectifier, 6 capacitors, a spark gap, and a flat coil. A metal disk is mounted in a liquid-filled tube and is placed in close proximity to the flat coil. Due to the repulsive force existing between the coil and disk shock waves are generated, while an eddy current is induced in the metal disk. Some components and materials associated with the device are also described. By increasing the capacitance content to enhance electric energy level, a highly focused pressure can be achieved at the focal point through an acoustic lens in order to lyse fat tissue. Focused pressures were measured at the focal point and its vicinity for different operation voltages. The designed shock wave generator with an energy intensity of 0.0016 mJ/mm{sup 2} (at 4 kV) and 2000 firings or higher energy intensities with 1000 firings is found to be able to disrupt pig fat tissue.
Studies of laser-driven radiative blast waves
Edwards, M J; Hansen, J; Edens, A; Ditmire, T; Adams, R; Rambo, P; Ruggles, L; Smith, I; Porter, J
2004-04-29T23:59:59.000Z
We have performed two sets of experiments looking at laser-driven radiating blast waves. In one set of experiments the effect of a drive laser's passage through a background gas on the hydrodynamical evolution of blast waves was examined. It was found that the laser's passage heats a channel in the gas, creating a region where a portion of the blast wave front had an increased velocity, leading to the formation of a bump-like protrusion on the blast wave. The second set of experiments involved the use of regularly spaced wire arrays to induce perturbations on a blast wave surface. The decay of these perturbations as a function of time was measured for various wave number perturbations and found to be in good agreement with theoretical predictions.
auroral kilometric radiation: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Radiation (AKR) is generated by the accelerated electrons Strangeway, Robert J. 2 Propagation of electromagnetic waves in the source region of thePropagation of...
Enrico Montanari; Pierluigi Fortini
1998-08-26T23:59:59.000Z
The interaction of a gravitational wave with a system made of an RLC circuit forming one end of a mechanical harmonic oscillator is investigated. We show that, in some configurations, the coherent interaction of the wave with both the mechanical oscillator and the RLC circuit gives rise to a mechanical quality factor increase of the electromagnetic signal. When this system is used as an amplifier of gravitational periodic signals in the frequency range 50-1000 Hz, at ultracryogenic temperatures and for sufficiently long integration times (up to 4 months), a sensitivity of 10^(-24)-10^(-27) on the amplitude of the metric could be achieved when thermal noise, shot noise and amplifier back--action are considered.
Isotropic-medium three-dimensional cloaks for acoustic and electromagnetic waves
Urzhumov, Yaroslav; Smith, David R; 10.1063/1.3691242
2012-01-01T23:59:59.000Z
We propose a generalization of the two-dimensional eikonal-limit cloak derived from a conformal transformation to three dimensions. The proposed cloak is a spherical shell composed of only isotropic media; it operates in the transmission mode and requires no mirror or ground plane. Unlike the well-known omnidirectional spherical cloaks, it may reduce visibility of an arbitrary object only for a very limited range of observation angles. In the short-wavelength limit, this cloaking structure restores not only the trajectories of incident rays, but also their phase, which is a necessary ingredient to complete invisibility. Both scalar-wave (acoustic) and transverse vector-wave (electromagnetic) versions are presented.
Kuzmin, Dmitry A; Shavrov, Vladimir G
2014-01-01T23:59:59.000Z
Electrodynamic properties of the graphene - magnetic semiconductor - graphene sandwich-structure have been investigated theoretically with taking into account the dissipation processes. Influence of graphene layers on electromagnetic waves propagation in graphene - semi-infinte magnetic semiconductor and graphene - magnetic semiconductor - graphene sandwich-structure has been analyzed. Frequency and field dependences of the reflectance, transmittance and absorbtance of electromagnetic waves by such structure have been calculated. The size effects associated with the thickness of the structure have been analyzed. The possibility of efficient control of electrodynamic properties of graphene - magnetic semiconductor - graphene sandwich structure by an external magnetic field has been shown.
Electro-Optical Sensing Apparatus and Method for Characterizing Free-Space Electromagnetic Radiation
Zhang, Xi-Cheng; Libelo, Louis Francis; Wu, Qi
1999-09-14T23:59:59.000Z
Apparatus and methods for characterizing free-space electromagnetic energy, and in particular, apparatus/method suitable for real-time two-dimensional far-infrared imaging applications are presented. The sensing technique is based on a non-linear coupling between a low-frequency electric field and a laser beam in an electro-optic crystal. In addition to a practical counter-propagating sensing technique, a co-linear approach is described which provides longer radiated field--optical beam interaction length, thereby making imaging applications practical.
Vagin, K. Yu., E-mail: vagin@sci.lebedev.ru; Uryupin, S. A., E-mail: uryupin@sci.lebedev.ru [Russian Academy of Sciences, Lebedev Physical Institute (Russian Federation)
2013-08-15T23:59:59.000Z
The reflection of a test electromagnetic pulse from the plasma formed as a result of tunnel ionization of atoms in the field of a circularly polarized high-power radiation pulse is analyzed using the kinetic approach to describe electron motion. It is shown that the reflected pulse is significantly amplified due to the development of Weibel instability. The amplification efficiency is determined by the maximum value of the instability growth rate, which depends on the degree of anisotropy of the photoelectron distribution function.
The Radiation Dose Measurement System for the BaBar Electromagnetic Calorimeter
Khan, A.; /Brunel U.; Meyer, W.T.; /Iowa State U.; Stelzer, J.; /Stanford U., Phys. Dept.; Yi, Jong; /Manchester U.
2006-08-14T23:59:59.000Z
An array of 116 p-channel radiation sensitive MOSFET transistors (RadFETs) has been operational for the past 6 years at the BaBar experiment at the PEP-II asymmetric B-Factory at the Stanford Linear Accelerator Center (SLAC). This system maps the integrated dose absorbed by different regions of the Electromagnetic Calorimeter (EMC) during the running of the experiment. We report on the design and implementation of the system and finally, the performance of the monitoring system during the last 6 years of BaBar data-taking.
Scattering of electromagnetic waves by many thin cylinders: theory and computational modeling
Ramm, A G
2015-01-01T23:59:59.000Z
Electromagnetic (EM) wave scattering by many parallel infinite cylinders is studied asymptotically as a tends to 0, where a is the radius of the cylinders. It is assumed that the centres of the cylinders are distributed so that their numbers is determined by some positive function N(x). The function N(x) >= 0 is a given continuous function. An equation for the self-consistent (limiting) field is derived as a tends to 0. The cylinders are assumed perfectly conducting. Formula for the effective refraction coefficient of the new medium, obtained by embedding many thin cylinders into a given region, is derived. The numerical results presented demonstrate the validity of the proposed approach and its efficiency for solving the many-body scattering problems, as well as the possibility to create media with negative refraction coefficients.
Phase field method to optimize dielectric devices for electromagnetic wave propagation
Takezawa, Akihiro, E-mail: akihiro@hiroshima-u.ac.jp; Kitamura, Mitsuru, E-mail: kitamura@naoe.hiroshima-u.ac.jp
2014-01-15T23:59:59.000Z
We discuss a phase field method for shape optimization in the context of electromagnetic wave propagation. The proposed method has the same functional capabilities as the level set method for shape optimization. The first advantage of the method is the simplicity of computation, since extra operations such as re-initialization of functions are not required. The second is compatibility with the topology optimization method due to the similar domain representation and the sensitivity analysis. Structural shapes are represented by the phase field function defined in the design domain, and this function is optimized by solving a time-dependent reaction diffusion equation. The artificial double-well potential function used in the equation is derived from sensitivity analysis. We study four types of 2D or 2.5D (axisymmetric) optimization problems. Two are the classical problems of photonic crystal design based on the Bloch theory and photonic crystal wave guide design, and two are the recent topics of designing dielectric left-handed metamaterials and dielectric ring resonators.
Radiative precursors driven by converging blast waves in noble gases
Burdiak, G. C.; Lebedev, S. V.; Harvey-Thompson, A. J.; Swadling, G. F.; Suzuki-Vidal, F.; Hall, G. N.; Khoory, E.; Pickworth, L.; Bland, S. N.; Grouchy, P. de; Skidmore, J.; Suttle, L.; Bennett, M.; Niasse, N. P. L. [Blackett Laboratory, Imperial College London SW7 2BW (United Kingdom)] [Blackett Laboratory, Imperial College London SW7 2BW (United Kingdom); Williams, R. J. R. [Atomic Weapons Establishment, Aldermaston RG7 4PR (United Kingdom)] [Atomic Weapons Establishment, Aldermaston RG7 4PR (United Kingdom); Blesener, K.; Atoyan, L.; Cahill, A.; Hoyt, C.; Potter, W. [Laboratory of Plasma Studies, Cornell University, Ithaca, New York 14853 (United States)] [Laboratory of Plasma Studies, Cornell University, Ithaca, New York 14853 (United States); and others
2014-03-15T23:59:59.000Z
A detailed study of the radiative precursor that develops ahead of converging blast waves in gas-filled cylindrical liner z-pinch experiments is presented. The experiment is capable of magnetically driving 20?km s{sup ?1} blast waves through gases of densities of the order 10{sup ?5} g cm{sup ?3} (see Burdiak et al. [High Energy Density Phys. 9(1), 52–62 (2013)] for a thorough description). Data were collected for Ne, Ar, and Xe gas-fills. The geometry of the setup allows a determination of the plasma parameters both in the precursor and across the shock, along a nominally uniform line of sight that is perpendicular to the propagation of the shock waves. Radiation from the shock was able to excite NeI, ArII, and XeII/XeIII precursor spectral features. It is shown that the combination of interferometry and optical spectroscopy data is inconsistent with upstream plasmas being in LTE. Specifically, electron density gradients do not correspond to any apparent temperature change in the emission spectra. Experimental data are compared to 1D radiation hydrodynamics HELIOS-CR simulations and to PrismSPECT atomic physics calculations to assist in a physical interpretation of the observations. We show that upstream plasma is likely in the process of being radiatively heated and that the emission from a small percentage of ionised atoms within a cool background plasma dominates the emission spectra. Experiments were carried out on the MAGPIE and COBRA pulsed-power facilities at Imperial College London and Cornell University, respectively.
Colavita, E. [Colegio de Ciencia y Tecnología, Universidad Autónoma de la Ciudad de México, México, D.F., 09790 (Mexico)] [Colegio de Ciencia y Tecnología, Universidad Autónoma de la Ciudad de México, México, D.F., 09790 (Mexico); Hacyan, S., E-mail: hacyan@fisica.unam.mx [Instituto de Física, Universidad Nacional Autónoma de México, A. P. 20-364, México D. F., 01000 (Mexico)
2014-03-15T23:59:59.000Z
We analyze the solutions of the Klein–Gordon and Dirac equations describing a charged particle in an electromagnetic plane wave combined with a magnetic field parallel to the direction of propagation of the wave. It is shown that the Klein–Gordon equation admits coherent states as solutions, while the corresponding solutions of the Dirac equation are superpositions of coherent and displaced-number states. Particular attention is paid to the resonant case in which the motion of the particle is unbounded. -- Highlights: •We study a relativistic electron in a particular electromagnetic field configuration. •New exact solutions of the Klein–Gordon and Dirac equations are obtained. •Coherent and displaced number states can describe a relativistic particle.
Ehud Nakar; Tsvi Piran
2011-02-04T23:59:59.000Z
The question "what is the observable electromagnetic (EM) signature of a compact binary merger?" is an intriguing one with crucial consequences to the quest for gravitational waves (GW). Compact binary mergers are prime sources of GW, targeted by current and next generation detectors. Numerical simulations have demonstrated that these mergers eject energetic sub-relativistic (or even relativistic) outflows. This is certainly the case if the mergers produce short GRBs, but even if not, significant outflows are expected. The interaction of such outflows with the surround matter inevitably leads to a long lasting radio signal. We calculate the expected signal from these outflows (our calculations are also applicable to short GRB orphan afterglows) and we discuss their detectability. We show that the optimal search for such signal should, conveniently, take place around 1.4 GHz. Realistic estimates of the outflow parameters yield signals of a few hundred $\\mu$Jy, lasting a few weeks, from sources at the detection horizon of advanced GW detectors. Followup radio observations, triggered by GW detection, could reveal the radio remnant even under unfavorable conditions. Upcoming all sky surveys can detect a few dozen, and possibly even thousands, merger remnants at any give time, thereby providing robust merger rate estimates even before the advanced GW detectors become operational. In fact, the radio transient RT 19870422 fits well the overall properties predicted by our model and we suggest that its most probable origin is a compact binary merger radio remnant.
Zhang, Xingyu; Subbaraman, Harish; Wang, Shiyi; Zhan, Qiwen; Luo, Jingdong; Jen, Alex K -Y; Chung, Chi-jui; Yan, Hai; Pan, Zeyu; Nelson, Robert L; Lee, Charles Y -C; Chen, Ray T
2015-01-01T23:59:59.000Z
In this work, we design, fabricate and characterize a compact, broadband and highly sensitive integrated photonic electromagnetic field sensor based on a silicon-organic hybrid modulator driven by a bowtie antenna. The large electro-optic (EO) coefficient of organic polymer, the slow-light effects in the silicon slot photonic crystal waveguide (PCW), and the broadband field enhancement provided by the bowtie antenna, are all combined to enhance the interaction of microwaves and optical waves, enabling a high EO modulation efficiency and thus a high sensitivity. The modulator is experimentally demonstrated with a record-high effective in-device EO modulation efficiency of r33=1230pm/V. Modulation response up to 40GHz is measured, with a 3-dB bandwidth of 11GHz. The slot PCW has an interaction length of 300um, and the bowtie antenna has an area smaller than 1cm2. The bowtie antenna in the device is experimentally demonstrated to have a broadband characteristics with a central resonance frequency of 10GHz, as we...
Fannjiang, Albert
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering, Straining, and Mode and Applied Mathematics Vol. 61, No. 5, pp. 1545-1577 RADIATIVE TRANSFER OF SOUND WAVES IN A RANDOM FLOW the sound wave propagation in a random flow, whose mean flow is large compared with its fluctuation
STUDIES OF LASER-DRIVEN RADIATIVE BLAST WAVES A.D. EDENS1
Ditmire, Todd
-driven radiating blast waves. In the first set of experiments the effect of a drive laser's passage throughSTUDIES OF LASER-DRIVEN RADIATIVE BLAST WAVES A.D. EDENS1 , T. DITMIRE1 , J.F. HANSEN2 , M a background gas on the hydrodynamical evolution of blast waves was examined. The laser's passage heated
Decoherence of matter waves by thermal emission of radiation
Lucia Hackermueller; Klaus Hornberger; Bjoern Brezger; Anton Zeilinger; Markus Arndt
2004-02-19T23:59:59.000Z
Emergent quantum technologies have led to increasing interest in decoherence - the processes that limit the appearance of quantum effects and turn them into classical phenomena. One important cause of decoherence is the interaction of a quantum system with its environment, which 'entangles' the two and distributes the quantum coherence over so many degrees of freedom as to render it unobservable. Decoherence theory has been complemented by experiments using matter waves coupled to external photons or molecules, and by investigations using coherent photon states, trapped ions and electron interferometers. Large molecules are particularly suitable for the investigation of the quantum-classical transition because they can store much energy in numerous internal degrees of freedom; the internal energy can be converted into thermal radiation and thus induce decoherence. Here we report matter wave interferometer experiments in which C70 molecules lose their quantum behaviour by thermal emission of radiation. We find good quantitative agreement between our experimental observations and microscopic decoherence theory. Decoherence by emission of thermal radiation is a general mechanism that should be relevant to all macroscopic bodies.
Electromagnetic or other directed energy pulse launcher
Ziolkowski, Richard W. (Livermore, CA)
1990-01-01T23:59:59.000Z
The physical realization of new solutions of wave propagation equations, such as Maxwell's equations and the scaler wave equation, produces localized pulses of wave energy such as electromagnetic or acoustic energy which propagate over long distances without divergence. The pulses are produced by driving each element of an array of radiating sources with a particular drive function so that the resultant localized packet of energy closely approximates the exact solutions and behaves the same.
Vortex flow in the technology of radiation wave cracking (RWC)
L. A. Tsoy; V. N. Kolushov; A. G. Komarov; A. N. Tsoy
2012-09-16T23:59:59.000Z
This article examines the theory of vortex flows in relation to the processes occurring in the radiation-wave cracking of crude oil, when the crude oil is sprayed into the gas stream in the form of a mist and then is fed into the reactor, where it is treated by the accelerated electrons and the UHF radiation. The output of this process are the products with the specified parameters (high-octane petroleum products). This process operates at the ambient pressure and temperature, which makes the process safer for industrial purposes. Besides the process itself, the authors described the equipment used in this process, as well as the parameters of the optimal process.
Systematics of S- and P-wave radiation widths
Moore, M.S.
1980-09-22T23:59:59.000Z
The question of calculating differences in s- and p-wave radiation widths as a valid evaluation tool is explored. A purely statistical approach such as that provided by the Brink-Axel formula depends upon two factors: 1) an adequate description of the giant dipole resonance shape at energies well below the resonance, and 2) an adequate description of the level densities between the ground state and the excitation of the compound nucleus near the neutron separation energy. Some success has been obtained in certain regions of the periodic table with this simple approach, e.g., in the actinides where all nuclei exhibit similar rigid permanent deformations. However, if the method is to be used as a general evaluation procedure throughout the periodic table and particularly in regions where the radiative transition probabilities are enhanced by direct processes, it appears that much more nuclear structure information needs to be incorporated into the calculations.
Despax, B.; Pascal, O.; Gherardi, N.; Naude, N.; Belinger, A.; Pitchford, L. C.
2012-10-01T23:59:59.000Z
This study is focused on the power deposition in microplasma jet discharges generated by application of radiofrequency (RF) excitation to a hollow needle electrode. The plasma jet is initiated at atmospheric pressure in open air with a flow of helium through the electrode. We show that in this configuration, a significant part of the injected power is dissipated in electromagnetic radiation. Many recent works have demonstrated the potential of either cold plasma jets or of RF radiation for applications in medicine, and therefore a source that produces both a cold plasma jet and RF radiation could be of interest.
Klemas, Thomas J. (Thomas Jonas)
2005-01-01T23:59:59.000Z
As technology advances and sophisticated electronic systems achieve ubiquity, the demand for thorough, efficient Electromagnetic (EM) analysis continues to rise. The prohibitive costs of constructing and maintaining ...
Radiation-induced solitary waves in hot plasmas of accretion disks
Fedor V. Prigara
2005-07-08T23:59:59.000Z
It is shown that the existence of radiation-induced solitary waves in hot plasmas of accretion disks depends on the radial temperature profile.
Jenet, Fredrick A
2014-01-01T23:59:59.000Z
Searches for gravitational-wave backgrounds using pulsar timing arrays look for correlations in the timing residuals induced by the background across the pulsars in the array. The correlation signature of an isotropic, unpolarized gravitational-wave background predicted by general relativity follows the so-called Hellings and Downs curve, which is a relatively simple function of the angle between a pair of pulsars. To aid students and beginning researchers interested in pulsar timing, we give a pedagogical discussion of the Helling and Downs curve for pulsar timing arrays, considering simpler analogous scenarios involving sound and electromagnetic waves. We calculate Hellings-and-Downs type functions for these two scenarios and develop a framework suitable for doing more general correlation calculations.
Fredrick A. Jenet; Joseph D. Romano
2014-12-03T23:59:59.000Z
Searches for gravitational-wave backgrounds using pulsar timing arrays look for correlations in the timing residuals induced by the background across the pulsars in the array. The correlation signature of an isotropic, unpolarized gravitational-wave background predicted by general relativity follows the so-called Hellings and Downs curve, which is a relatively simple function of the angle between a pair of pulsars. To aid students and beginning researchers interested in pulsar timing, we give a pedagogical discussion of the Helling and Downs curve for pulsar timing arrays, considering simpler analogous scenarios involving sound and electromagnetic waves. We calculate Hellings-and-Downs type functions for these two scenarios and develop a framework suitable for doing more general correlation calculations.
Sainath, Kamalesh
2015-01-01T23:59:59.000Z
We propose a full-wave pseudo-analytical numerical electromagnetic (EM) algorithm to model subsurface induction sensors, traversing planar-layered geological formations of arbitrary EM material anisotropy and loss, which are used, for example, in the exploration of hydrocarbon reserves. Unlike past pseudo-analytical planar-layered modeling algorithms that impose parallelism between the formation's bed junctions however, our method involves judicious employment of Transformation Optics techniques to address challenges related to modeling arbitrarily-oriented, relative slope (i.e., tilting) between said junctions. The algorithm exhibits this flexibility, both with respect to anisotropy in the formation layers as well as junction tilting, via employing special planar slabs that coat each "flattened" (i.e., originally tilted) planar interface, locally redirecting the incident wave within the coating slabs to cause wave fronts to interact with the flattened interfaces as if they were still tilted with a specific, ...
J. Geng; G. T. Campbell; J. Bernu; D. Higginbottom; B. M. Sparkes; S. M. Assad; W. P. Zhang; N. P. Robins; P. K. Lam; B. C. Buchler
2014-08-11T23:59:59.000Z
We report on the delay of optical pulses using electromagnetically induced transparency in an ensemble of cold atoms with an optical depth exceeding 500. To identify the regimes in which four-wave mixing impacts on EIT behaviour, we conduct the experiment in both rubidium 85 and rubidium 87. Comparison with theory shows excellent agreement in both isotopes. In rubidium 87, negligible four-wave mixing was observed and we obtained one pulse-width of delay with 50% efficiency. In rubidium 85, four-wave-mixing contributes to the output. In this regime we achieve a delay-bandwidth product of 3.7 at 50% efficiency, allowing temporally multimode delay, which we demonstrate by compressing two pulses into the memory medium.
O. Skjaeraasen; A. Melatos; A. Spitkovsky
2005-08-08T23:59:59.000Z
A 2.5-dimensional particle-in-cell code is used to investigate the propagation of a large-amplitude, superluminal, nearly transverse electromagnetic (TEM) wave in a relativistically streaming electron-positron plasma with and without a shock. In the freestreaming, unshocked case, the analytic TEM dispersion relation is verified, and the streaming is shown to stabilize the wave against parametric instabilities. In the confined, shocked case, the wave induces strong, coherent particle oscillations, heats the plasma, and modifies the shock density profile via ponderomotive effects. The wave decays over $\\gtrsim 10^2$ skin depths; the decay length scale depends primarily on the ratio between the wave frequency and the effective plasma frequency, and on the wave amplitude. The results are applied to the termination shock of the Crab pulsar wind, where the decay length-scale (at least 0.05") might be comparable to the thickness of filamentary, variable substructure observed in the optical and X-ray wisps and knots.
A Topological Structure in the Set of Classical Free Radiation Electromagnetic Fields
A. F. Ranada; A. Tiemblo
2014-07-29T23:59:59.000Z
The aim of this work is to proceed with the development of a model of topological electromagnetism in empty space, proposed by one of us some time ago and based on the existence of a topological structure associated with the radiation fields in standard Maxwell's theory. This structure consists in pairs of complex scalar fields, say $\\phi$ and $\\theta$, that can be interpreted as maps $\\phi,\\theta: S^3\\mapsto S^2$, the level lines of which are orthogonal to one another, where $S^3$ is the compactified physical 3-space $R^3$, with only one point at infinity, and $S^2$ is the 2-sphere identified with the complete complex plane. These maps were discovered and studied in 1931 by the German mathematician H. Hopf, who showed that the set of all of them can be ordered in homotopy classes, labeled by the so called Hopf index, equal to $\\gamma=\\pm 1,\\,\\pm 2,\\,\\cdots ,\\, \\pm k,...$ but without $\\gamma=0$. In the model presented here and at the level of the scalars $\\phi$ and $\\theta$, the equations of motion are highly nonlinear; however there is a transformation of variables that converts exactly these equations (not by truncation!) into the linear Maxwell's ones for the magnetic and electric fields $\\B$ and $\\E$.
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering and ModeCoupling
Ryzhik, Lenya
Radiative Transfer of Sound Waves in a Random Flow: Turbulent Scattering and ModeÂCoupling Albert the sound wave propagation in a random flow, whose mean flow is large compared with its fluctuation and the turbulent scattering and modeÂcoupling of sound waves. We show that, because of the flowÂstraining term
N. B. Phillips; A. V. Gorshkov; I. Novikova
2009-03-24T23:59:59.000Z
We experimentally and theoretically analyze the propagation of weak signal field pulses under the conditions of electromagnetically induced transparency (EIT) in hot Rb vapor, and study the effects of resonant four-wave mixing (FWM). In particular, we demonstrate that in a double-$\\Lambda$ system, formed by the strong control field with the weak resonant signal and a far-detuned Stokes field, both continuous-wave spectra and pulse propagation dynamics for the signal field depend strongly on the amplitude of the seeded Stokes field, and the effect is enhanced in optically dense atomic medium. We also show that the theory describing the coupled propagation of the signal and Stokes fields is in good agreement with the experimental observations.
Wave-wave interactions in solar type III radio bursts
Thejappa, G. [Department of Astronomy, University of Maryland, College Park, MD 20742 (United States); MacDowall, R. J. [NASA/Goddard Space Flight Center, Greenbelt MD 20771 (United States)
2014-02-11T23:59:59.000Z
The high time resolution observations from the STEREO/WAVES experiment show that in type III radio bursts, the Langmuir waves often occur as localized magnetic field aligned coherent wave packets with durations of a few ms and with peak intensities well exceeding the strong turbulence thresholds. Some of these wave packets show spectral signatures of beam-resonant Langmuir waves, down- and up-shifted sidebands, and ion sound waves, with frequencies, wave numbers, and tricoherences satisfying the resonance conditions of the oscillating two stream instability (four wave interaction). The spectra of a few of these wave packets also contain peaks at f{sub pe}, 2f{sub pe} and 3 f{sub pe} (f{sub pe} is the electron plasma frequency), with frequencies, wave numbers and bicoherences (computed using the wavelet based bispectral analysis techniques) satisfying the resonance conditions of three wave interactions: (1) excitation of second harmonic electromagnetic waves as a result of coalescence of two oppositely propagating Langmuir waves, and (2) excitation of third harmonic electromagnetic waves as a result of coalescence of Langmuir waves with second harmonic electromagnetic waves. The implication of these findings is that the strong turbulence processes play major roles in beam stabilization as well as conversion of Langmuir waves into escaping radiation in type III radio bursts.
Cole, Benjamin
2012-10-19T23:59:59.000Z
Uncertainties associated with the microphysical and radiative properties of ice clouds remain an active research area because of the importance these clouds have in atmospheric radiative transfer problems and the energy balance of the Earth...
Cole, Benjamin
2012-10-19T23:59:59.000Z
Uncertainties associated with the microphysical and radiative properties of ice clouds remain an active research area because of the importance these clouds have in atmospheric radiative transfer problems and the energy balance of the Earth...
Henning, F. D., E-mail: farranalfonso@gmail.com; Mace, R. L., E-mail: macer@ukzn.ac.za [School of Chemistry and Physics, University of KwaZulu-Natal, Westville Campus, Private Bag X54001, Durban 4000 (South Africa)
2014-04-15T23:59:59.000Z
Electromagnetic ion cyclotron (EMIC) waves in multi-ion species plasmas propagate in branches. Except for the branch corresponding to the heaviest ion species, which has only a resonance at its gyrofrequency, these branches are bounded below by a cutoff frequency and above by a resonant gyrofrequency. The condition for wave growth is determined by the thermal anisotropies of each ion species, j, which sets an upper bound, ?{sub j}{sup ?}, on the wave frequency below which that ion species contributes positively to the growth rate. It follows that the relative positions of the cutoffs and the critical frequencies ?{sub j}{sup ?} play a crucial role in determining whether a particular wave branch will be unstable. The effect of the magnetospheric ion abundances on the growth rate of each branch of the EMIC instability in a model where all the ion species have kappa velocity distributions is investigated by appealing to the above ideas. Using the variation of the cutoff frequencies predicted by cold plasma theory as a guide, optimal ion abundances that maximise the EMIC instability growth rate are sought. When the ring current is comprised predominantly of H{sup +} ions, all branches of the EMIC wave are destabilised, with the proton branch having the maximum growth rate. When the O{sup +} ion abundance in the ring current is increased, a decrease in the growth rate of the proton branch and cyclotron damping of the helium branch are observed. The oxygen branch, on the other hand, experiences an increase in the maximum growth rate with an increase in the O{sup +} ion abundance. When the ring current is comprised predominantly of He{sup +} ions, only the helium and oxygen branches of the EMIC wave are destabilised, with the helium branch having the maximum growth rate.
Luis C. B. Crispino; Atsushi Higuchi; George E. A. Matsas
2010-12-16T23:59:59.000Z
We investigate the low-frequency absorption cross section of the electromagnetic waves for the extreme Reissner-Nordstrom black holes in higher dimensions. We first construct the exact solutions to the relevant wave equations in the zero-frequency limit. In most cases it is possible to use these solutions to find the transmission coefficients of partial waves in the low-frequency limit. We use these transmission coefficients to calculate the low-frequency absorption cross section in five and six spacetime dimensions. We find that this cross section is dominated by the modes with l=2 in the spherical-harmonic expansion rather than those with l=1, as might have been expected, because of the mixing between the electromagnetic and gravitational waves. We also find an upper limit for the low-frequency absorption cross section in dimensions higher than six.
Zhang, Xi-Cheng; Riordan, Jenifer Ann; Sun, Feng-Guo
2000-08-29T23:59:59.000Z
Apparatus and methods for characterizing free-space electromagnetic energy, and in particular, apparatus/method suitable for real-time two-dimensional far-infrared imaging applications are presented. The sensing technique is based on a non-linear coupling between a low-frequency electric (or magnetic) field and a laser beam in an electro-optic (or magnetic-optic) crystal. In addition to a practical counter-propagating sensing technique, a co-linear approach is described which provides longer radiated field-optical beam interaction length, thereby making imaging applications practical.
On the Tropospheric Response to Anomalous Stratospheric Wave Drag and Radiative Heating
On the Tropospheric Response to Anomalous Stratospheric Wave Drag and Radiative Heating DAVID W. J of anomalous diabatic heating in the polar stratosphere as stratospheric temperatures relax to climatology
The Electric Field and Waves Instruments on the Radiation Belt Storm Probes Mission
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 ...
Boris V. Gisin
2014-05-13T23:59:59.000Z
The Dirac equation, in the field of a traveling circularly polarized electromagnetic wave and a constant magnetic field, has singular solutions, corresponding the expansion of energy in vicinity of some singular point. These solutions described relativistic fermions. States relating to these solutions are not stationary. The temporal change of average energy, momentum and spin for single and mixed states is studied in the paper. A distinctive feature of the states is the disappearance of the longitudinal component of the average spin. Another feature is the equivalence of the condition of fermion minimal energy and the classical condition of the magnetic resonance. Finding such solutions assumes the use of a transformation for rotating and co-moving frames of references. Comparison studies of solutions obtained with the Galilean and non-Galilean transformation shown that some parameters of the non-Galilean transformation may be measured in high-energy physics.
Scattering of an ultrashort electromagnetic radiation pulse by an atom in a broad spectral range
Astapenko, V. A., E-mail: astval@mail.ru [Moscow Institute of Physics and Technology (Russian Federation)
2011-02-15T23:59:59.000Z
The scattering of an ultrashort electromagnetic pulse by atomic particles is described using a consistent quantum-mechanical approach taking into account excitation of a target and nondipole electromagnetic interaction, which is valid in a broad spectral range. This approach is applied to the scattering of single- and few-cycle pulses by a multielectron atom and a hydrogen atom. Scattering spectra are obtained for ultrashort pulses of different durations. The relative contribution of 'elastic' scattering of a single-cycle pulse by a hydrogen atom is studied in the high-frequency limit as a function of the carrier frequency and scattering angle.
Richard H. Price; John W. Belcher; David A. Nichols
2012-12-19T23:59:59.000Z
We compare the nature of electromagnetic fields and of gravitational fields in linearized general relativity. We carry out this comparison both mathematically and visually. In particular the "lines of force" visualizations of electromagnetism are contrasted with the recently introduced tendex/vortex eigenline technique for visualizing gravitational fields. Specific solutions, visualizations, and comparisons are given for an oscillating point quadrupole source. Among the similarities illustrated are the quasistatic nature of the near fields, the transverse 1/r nature of the far fields, and the interesting intermediate field structures connecting these two limiting forms. Among the differences illustrated are the meaning of field line motion, and of the flow of energy.
Theory of electromagnetic fields
Wolski, Andrzej
2011-01-01T23:59:59.000Z
We discuss the theory of electromagnetic fields, with an emphasis on aspects relevant to radiofrequency systems in particle accelerators. We begin by reviewing Maxwell's equations and their physical significance. We show that in free space, there are solutions to Maxwell's equations representing the propagation of electromagnetic fields as waves. We introduce electromagnetic potentials, and show how they can be used to simplify the calculation of the fields in the presence of sources. We derive Poynting's theorem, which leads to expressions for the energy density and energy flux in an electromagnetic field. We discuss the properties of electromagnetic waves in cavities, waveguides and transmission lines.
Mode structure in the far field radiation of a leaky-wave multiple quantum well laser
Nekorkin, S M; Zvonkov, B N; Karzanova, Maria V; Dikareva, Natalia V; Aleshkin, V Ya; Dubinov, A A
2012-10-31T23:59:59.000Z
The radiation patterns of a leaky-wave InGaAs/GaAs/InGaP laser are studied. In the subthreshold regime, several peaks are found, corresponding to the emission of fundamental and excited modes. The dependences of the amplitude, position and width of the peaks on the pump current are investigated and explained. (measurement of laser radiation parameters)
Jikang Chen
2010-03-01T23:59:59.000Z
The carrier or medium of electromagnetic waves has been vainly searched for many years, and now it has been caught after the establishment of the dynamic equations in photon gas. The photon's rest mass has been estimated from the cosmic background temperature in space where the photon gas is at an open state of thermal equilibrium, and the photon's proper magnetic moment is calculated from the dynamic equations of photon gas too. As the carrier of electromagnetic waves, the photon gas is a discrete medium at very high frequency, and then the Bohr's electron is hardly to emit energy in wave form and can be stably rounding the nuclei in discrete orbits at lower temperature.
Connecting the Electromagnetic and Gravitational Wave Skies in the Era of Advanced LIGO
McWilliams, Princeton U. 9:30 Â 10:30 "Gravitational-wave astronomy: past, present, and future-924-7855 138 Nassau Street, Princeton, NJ 08542 #12;High Energy EM Counterparts and Capabilities Thursday, 3 Lower Energy EM Counterparts and Capabilities Friday, 4 May 2012 9:30 Â 10:30 "Needle in a Haystack
Theory of Optical Leaky-Wave Antenna Integrated in a Ring Resonator for Radiation Control
Guclu, Caner; Capolino, Filippo
2015-01-01T23:59:59.000Z
The integration of a leaky-wave antenna with a ring resonator is presented using analytical guided wave models. The device consists of a ring resonator fed by a directional coupler, where the ring resonator path includes a leaky-wave antenna segment. The resonator integration provides two main advantages: the high-quality factor ensures effective control of radiation intensity by controlling the resonance conditions and the efficient radiation from a leaky-wave antenna even when its length is much smaller than the propagation length of the leaky wave. We devise an analytical model of the guided wave propagation along a directional coupler and the ring resonator path including the antenna and non-radiating segments. The trade-offs regarding the quality factor of resonance and the antenna efficiency of such a design is reported in terms of the coupler parameters, leaky-wave constant and radiation length. Finally a CMOS-compatible OLWA design suitable for the ring resonator integration is designed where Silicon ...
Spin and orbital angular momenta of electromagnetic waves in free space
Mansuripur, Masud [College of Optical Sciences, University of Arizona, Tucson, Arizona 85721 (United States)
2011-09-15T23:59:59.000Z
We derive exact expressions, in the form of Fourier integrals over the (k,{omega}) domain, for the energy, momentum, and angular momentum of a light pulse propagating in free space. The angular momentum is seen to split naturally into two parts. The spin contribution of each plane-wave constituent of the pulse, representing the difference between its right- and left-circular polarization content, is aligned with the corresponding k-vector. In contrast, the orbital angular momentum associated with each plane-wave is orthogonal to its k-vector. In general, the orbital angular momentum content of the wavepacket is the sum of an intrinsic part, due, for example, to phase vorticity, and an extrinsic part, r{sub CM} x p, produced by the linear motion of the center-of-mass r{sub CM} of the light pulse in the direction of its linear momentum p.
Sheng-Jun Yang; Xiao-Hui Bao; Jian-Wei Pan
2015-05-03T23:59:59.000Z
Coherent manipulation of single-photon wave packets is essentially important for optical quantum communication and quantum information processing. In this paper, we realize controllable splitting and modulation of single-photon-level pulses by using a tripod-type atomic medium. The adoption of two control beams enable us to store one signal pulse into superposition of two distinct atomic collective excitations. By controlling the time delay between the two control pulses, we observe splitting of a stored wave packet into two temporally-distinct modes. By controlling the frequency detuning of the control beams, we observe both temporal and frequency-domain interference of the retrieval signal pulses, which provides a method for pulse modulation and multi-splitting of the signal photons.
Schmalz, Jelena A. [School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); Gureyev, Timur E. [CSIRO Materials Science and Engineering, PB 33, Clayton South MDC, VIC 3169 (Australia); School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); Paganin, David M. [School of Physics, Monash University, VIC 3800 (Australia); Pavlov, Konstantin M. [School of Science and Technology, University of New England, Armidale, NSW 2351 (Australia); School of Physics, Monash University, VIC 3800 (Australia)
2011-08-15T23:59:59.000Z
Although originally developed for coherent paraxial scalar electromagnetic radiation in the visible-light regime, phase retrieval using the transport-of-intensity equation has been successfully applied to a range of paraxial radiation and matter-wave fields. Such applications include using electron wave fields to quantitatively image magnetic skyrmions and spin ices, propagation-based phase-contrast imaging using cold neutrons and hard x-rays, and visible-light refractive imaging of the projected column density of cold-atom clouds. Teague's method for phase retrieval using the transport-of-intensity equation, which renders the phase of a paraxial complex wave indirectly measurable via the existence of a conserved current, has been applied to a broad variety of situations which include all of the experiments described above. However, these applications have been undertaken without a thorough analysis of the underlying validity of the method. Here we derive sufficient conditions for the phase-retrieval solution provided by Teague's method to coincide with the true phase of the paraxial radiation or matter-wave field. We also present a sufficient condition guaranteeing that the discrepancy between the true phase function and that reconstructed using Teague's solution is small. These conditions demonstrate that, in most practical cases, for phase-amplitude retrieval using the transport-of-intensity equation, the Teague solution is very close to the exact solution. However, we also describe a counter example in the context of phase-amplitude retrieval using hard x-rays, in which the relative root-mean-square difference between the exact solution and that obtained using Teague's method is 9%. These findings clarify the foundations of one of the most widely applied methods for propagation-based phase retrieval of both paraxial matter and radiation wave fields and define a region for its applicability.
Particle acceleration in superluminal strong waves
Teraki, Yuto; Nagataki, Shigehiro
2015-01-01T23:59:59.000Z
We calculate the electron acceleration in random superluminal strong waves (SLSWs) and radiation from them by using numerical methods in the context of the termination shock of the pulsar wind nebulae. We pursue the electrons by solving the equation of motion in the analytically expressed electromagnetic turbulences. These consist of primary SLSW and isotropically distributed secondary electromagnetic waves. Under the dominance of the secondary waves, all electrons gain nearly equal energy. On the other hand, when the primary wave is dominant, selective acceleration occurs. The phase of the primary wave felt by the electrons moving nearly along the wavevector changes very slowly compared to the oscillation of the wave, which is called "phase locked", and such electrons are continuously accelerated. This acceleration by SLSWs may play a crucial role in the pre-acceleration for the shock acceleration. In general, the radiation from the phase-locked population is different from the synchro-Compton radiation. How...
King, Benjamin L. [Radiation Oncology Department, University of Washington, Seattle, WA (United States); Butler, Wayne M., E-mail: wbutler@wheelinghospital.or [Schiffler Cancer Center, Wheeling Hospital, Wheeling, WV (United States); Wheeling Jesuit University, Wheeling, WV (United States); Merrick, Gregory S. [Schiffler Cancer Center, Wheeling Hospital, Wheeling, WV (United States); Wheeling Jesuit University, Wheeling, WV (United States); Kurko, Brian S.; Reed, Joshua L.; Murray, Brian C. [Schiffler Cancer Center, Wheeling Hospital, Wheeling, WV (United States); Wallner, Kent E. [Puget Sound Health Care System, Department of Veteran's Affairs, Seattle, VA (United States)
2011-04-01T23:59:59.000Z
Purpose: Real-time image guidance enables more accurate radiation therapy by tracking target movement. This study used transponder positions to monitor changes in prostate volume that may be a source of dosimetric and target inaccuracy. Methods and Materials: Twenty-four men with biopsy-proven T1c-T3a prostate cancer each had three electromagnetic transponders implanted transperineally. Their coordinates were recorded by the Calypso system, and the perimeter of the triangle formed by the transponders was used to calculate prostate volumes at sequential time points throughout the course of radiation therapy to a dose of 81 Gy in 1.8-Gy fractions. Results: There was a significant decrease in mean prostate volume of 10.9% from the first to the final day of radiation therapy. The volume loss did not occur monotonically but increased in most patients (75%) during the first several weeks to a median maximum on Day 7. The volume increased by a mean of 6.1% before decreasing by a mean maximum difference of 18.4% to nadir (p < 0.001 for both increase and decrease). Glandular shrinkage was asymmetric, with the apex to right base dimension varying more than twice that of the lateral dimension. For all dimensions, the mean change was <0.5 cm. Conclusion: Real-time transponder positions indicated a volume increase during the initial days of radiation therapy and then significant and asymmetric shrinkage by the final day. Understanding and tracking volume fluctuations of the prostate during radiation therapy can help real-time imaging technology perform to its fullest potential.
Internal wave energy radiated from a turbulent mixed layer
Munroe, James R., E-mail: jmunroe@mun.ca [Department of Physics and Physical Oceanography, Memorial University of Newfoundland, St. John's, Newfoundland A1B 3X7 (Canada); Sutherland, Bruce R., E-mail: bsuther@ualberta.ca [Departments of Physics and Earth and Atmospheric Sciences, University of Alberta, Edmonton, Alberta T6G 2R3 (Canada)
2014-09-15T23:59:59.000Z
We examine mixed-layer deepening and the generation of internal waves in stratified fluid resulting from turbulence that develops in response to an applied surface stress. In laboratory experiments the stress is applied over the breadth of a finite-length tank by a moving roughened conveyor belt. The turbulence in the shear layer is characterized using particle image velocimetry to measure the kinetic energy density. The internal waves are measured using synthetic schlieren to determine their amplitudes, frequencies, and energy density. We also perform fully nonlinear numerical simulations restricted to two dimensions but in a horizontally periodic domain. These clearly demonstrate that internal waves are generated by transient eddies at the integral length scale of turbulence and which translate with the background shear along the base of the mixed layer. In both experiments and simulations we find that the energy density of the generated waves is 1%–3% of the turbulent kinetic energy density of the turbulent layer.
Florida, University of
IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 47, NO. 3, AUGUST 2005 521 Abstract--It is known from both theory and numerical simula- tions that a current pulse suffers apparent electromagnetic field structure is non-transverse electromagnetic (TEM), particu- larly near the source region
Francesco Bariani; Iacopo Carusotto
2010-02-01T23:59:59.000Z
We present a Maxwell-Bloch description of the dynamics of a light pulse propagating through a spatially inhomogeneous system consisting of alternating layers of EIT media and vacuum. We study the effect of a dynamical modulation of the EIT control field on the shape of the wave packet: interesting effects due to the presence of interfaces with group velocity mismatch are found. An effective description based on a continuity equation is developed. Modulation schemes that can be realized in ultracold atomic samples with standard experimental techniques are proposed and discussed.
Experimental methodology for non-thermal effects of electromagnetic radiation on biologics
Cox, Felicia C. A. I
2006-01-01T23:59:59.000Z
Appropriate equipment is needed for research on the effects of radio-frequency radiation from radio-frequency identification (RF-ID) systems on biological materials. In the present study, a complete test system comprising ...
The response of certain stored products insects to various wavebands of electromagnetic radiation
Stermer, Raymond Andrew
1958-01-01T23:59:59.000Z
?Numbers refer to referenoee listed in the bibliography. attracted to' blaok light, ultraviolet. Inseot traps using eleotromag-, netio radiation are reooszzsn4ed by Tenhet and Bare as a survey tool to 6 reflect the degree of infestation in tobacoo... INSECTS TO VARIOUS WAVESANDS OP ELECTRONAGNETIC RADIATION INTRODUCTION Interest in the attraotion of inseots to fire and light dates baok to the dsye of primitive man. From early literature such as "the Sanskrit EKooh~~atiks attributed to King Sudraka...
Jordan Camp; Scott D. Barthelmy; Lindy Blackburn; Kenneth Carpenter; Neil Gehrels; Jonah Kanner; Frank E. Marshall; Judith L. Racusin; Takanori Sakamoto
2013-04-12T23:59:59.000Z
The International Space Station offers a unique platform for rapid and inexpensive deployment of space telescopes. A scientific opportunity of great potential later this decade is the use of telescopes for the electromagnetic follow-up of ground-based gravitational wave detections of neutron star and black hole mergers. We describe this possibility for OpTIIX, an ISS technology demonstration of a 1.5 m diffraction limited optical telescope assembled in space, and ISS-Lobster, a wide-field imaging X-ray telescope now under study as a potential NASA mission. Both telescopes will be mounted on pointing platforms, allowing rapid positioning to the source of a gravitational wave event. Electromagnetic follow-up rates of several per year appear likely, offering a wealth of complementary science on the mergers of black holes and neutron stars.
Radiation in Yang-Mills formulation of gravity and a generalized pp-wave metric
S. Baskal
1997-12-23T23:59:59.000Z
The variational methods implemented on a quadratic Yang-Mills type Lagrangian yield two sets of equations interpreted as the field equations and the energy-momentum tensor for the gravitational field. A covariant condition is imposed on the energy-momentum tensor to represent the radiation field. A generalized pp-wave metric is found to simultaneously satisfy both the field equations and the radiation condition. The result is compared with that of Lichn\\'{e}rowicz.
Laser beat wave excitation of terahertz radiation in a plasma slab
Chauhan, Santosh; Parashar, Jetendra, E-mail: j.p.parashar@gmail.com [Department of Applied Physics, Samrat Ashok Technological Institute, Vidisha 464001, Madhya Pradesh (India)
2014-10-15T23:59:59.000Z
Terahertz (THz) radiation generation by nonlinear mixing of lasers, obliquely incident on a plasma slab is investigated. Two cases are considered: (i) electron density profile is parabolic but density peak is below the critical density corresponding to the beat frequency, (ii) plasma boundaries are sharp and density is uniform. In both cases, nonlinearity arises through the ponderomotive force that gives rise to electron drift at the beat frequency. In the case of inhomogeneous plasma, non zero curl of the nonlinear current density gives rise to electromagnetic THz generation. In case of uniform plasma, the sharp density variation at the plasma boundaries leads to radiation generation. In a slab width of less than a terahertz wavelength, plasma density one fourth of terahertz critical density, laser intensities ?10{sup 17?}W/cm{sup 2} at 1??m, one obtains the THz intensity ?1?GW/cm{sup 2} at 3 THz radiation frequency.
Reed, Evan J. (Pine Island, MN); Armstrong, Michael R. (Albuquerque, NM)
2010-09-07T23:59:59.000Z
Strain waves of THz frequencies can coherently generate radiation when they propagate past an interface between materials with different piezoelectric coefficients. Such radiation is of detectable amplitude and contains sufficient information to determine the time-dependence of the strain wave with unprecedented subpicosecond, nearly atomic time and space resolution.
Radiative Thermal Noise for Transmissive Optics in Gravitational-Wave Detectors
Sheila Dwyer; Stefan W. Ballmer
2014-08-07T23:59:59.000Z
Radiative losses have traditionally been neglected in the calculation of thermal noise of transmissive optical elements because for the most commonly used geometries they are small compared to losses due to thermal conduction. We explore the use of such transmissive optical elements in extremely noise-sensitive environments such as the arm cavities of future gravitational-wave interferometers. This drives us to a geometry regime where radiative losses are no longer negligible. In this paper we derive the thermo-refractive noise associated with such radiative losses and compare it to other known sources of thermal noise.
On the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE
Sobel, Adam
of tropical cyclones; the theory then predicts the zonal separation distance of such tropical cyclone pairsOn the Wavelength of the Rossby Waves Radiated by Tropical Cyclones KYLE D. KROUSE Department cyclone (TC). In some cases, such disturbances undergo tropical cyclogenesis, resulting in a pair
Internal wave energy radiated from a turbulent mixed layer James R. Munroe1, a)
Sutherland, Bruce
Internal wave energy radiated from a turbulent mixed layer James R. Munroe1, a) and Bruce R in the shear layer is characterized using particle image velocimetry to measure the kinetic energy den- sity, and energy density. We also perform fully nonlinear numer- ical simulations restricted to two dimensions
Francesco Pannarale; Frank Ohme
2014-07-24T23:59:59.000Z
Coalescing neutron-star-black-hole (NS-BH) binaries are a promising source of gravitational-wave (GW) signals detectable with large-scale laser interferometers such as Advanced LIGO and Virgo. They are also one of the main short gamma-ray burst (SGRB) progenitor candidates. If the BH tidally disrupts its companion, an SGRB may be ignited when a sufficiently massive accretion disk forms around the remnant BH. Detecting an NS-BH coalescence both in the GW and electromagnetic (EM) spectrum offers a wealth of information about the nature of the source. How much can actually be inferred from a joint detection is unclear, however, as a mass/spin degeneracy may reduce the GW measurement accuracy. To shed light on this problem and on the potential of joint EM+GW observations, we here combine recent semi-analytical predictions for the remnant disk mass with estimates of the parameter-space portion that is selected by a GW detection. We identify cases in which an SGRB ignition is supported, others in which it can be excluded, and finally others in which the outcome depends on the chosen model for the currently unknown NS equation of state. We pinpoint a range of systems that would allow us to place lower bounds on the equation of state stiffness if both the GW emission and its EM counterpart are observed. The methods we develop can broaden the scope of existing GW detection and parameter-estimation algorithms and could allow us to disregard about half of the templates in an NS-BH search following an SGRB trigger, increasing its speed and sensitivity.
Cosmological Baryon Sound Waves Coupled with the Primeval Radiation
Kazuhiro Yamamoto; Naoshi Sugiyama; Humitaka Sato
1997-09-22T23:59:59.000Z
The fluid equations for the baryon-electron system in an expanding universe are derived from the Boltzmann equation. The effect of the Compton interaction is taken into account properly in order to evaluate the photon-electron collisional term. As an application, the acoustic motions of the baryon-electron system after recombination are investigated. The effective adiabatic index $\\gamma$ is computed for sound waves of various wavelengths, assuming the perturbation amplitude is small. The oscillations are found to be dumped when $\\gamma$ changes from between 1 (for an isothermal process) to 5/3 (for an adiabatic process).
Rossby wave radiation by an eddy on the polar beta-plane
Zhang, Yang
2015-01-01T23:59:59.000Z
Results from the laboratory experiments on the evolution of vortices (eddies) generated in a rotating tank with topographic beta-effect are presented. The surface elevation and velocity fields are measured by the Altimetric Imaging Velocimetry. The experiments are supplemented by shallow water numerical simulations as well as a linear theory which describes the Rossby wave radiation by travelling vortices. The cyclonic vortices observed in the experiments travel to the northwest and continuously radiate Rossby waves. Measurements show that initially axisymmetric vortices develop a dipolar component which enables them to perform translational motion. A pattern of alternating zonal jets to the west of the vortex is created by Rossby waves with approximately zonal crests. Energy spectra of the flows in the wavenumber space indicate that a wavenumber similar to that introduced by Rhines for turbulent flows on the beta-plane can be introduced here. The wavenumber is based on the translational speed of a vortex rat...
Amro, Hanan, E-mail: hanan.amro@gmail.com [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Hamstra, Daniel A.; Mcshan, Daniel L. [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States); Sandler, Howard [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States)] [Department of Radiation Oncology, Cedars-Sinai Medical Center, Los Angeles, California (United States); Vineberg, Karen; Hadley, Scott; Litzenberg, Dale [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)] [Department of Radiation Oncology, University of Michigan, Ann Arbor, Michigan (United States)
2013-01-01T23:59:59.000Z
Purpose: To study the impact of daily rotations and translations of the prostate on dosimetric coverage during radiation therapy (RT). Methods and Materials: Real-time tracking data for 26 patients were obtained during RT. Intensity modulated radiation therapy plans meeting RTOG 0126 dosimetric criteria were created with 0-, 2-, 3-, and 5-mm planning target volume (PTV) margins. Daily translations and rotations were used to reconstruct prostate delivered dose from the planned dose. D{sub 95} and V{sub 79} were computed from the delivered dose to evaluate target coverage and the adequacy of PTV margins. Prostate equivalent rotation is a new metric introduced in this study to quantify prostate rotations by accounting for prostate shape and length of rotational lever arm. Results: Large variations in prostate delivered dose were seen among patients. Adequate target coverage was met in 39%, 65%, and 84% of the patients for plans with 2-, 3-, and 5-mm PTV margins, respectively. Although no correlations between prostate delivered dose and daily rotations were seen, the data showed a clear correlation with prostate equivalent rotation. Conclusions: Prostate rotations during RT could cause significant underdosing even if daily translations were managed. These rotations should be managed with rotational tolerances based on prostate equivalent rotations.
Schleyer, F.; Cairns, Iver H. [School of Physics, University of Sydney, NSW 2006 (Australia); Kim, E.-H. [Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)
2013-03-15T23:59:59.000Z
Linear mode conversion (LMC) is the linear transfer of energy from one wave mode to another in an inhomogeneous plasma. It is relevant to laboratory plasmas and multiple solar system radio emissions, such as continuum radiation from planetary magnetospheres and type II and III radio bursts from the solar corona and solar wind. This paper simulates LMC of waves defined by warm, magnetized fluid theory, specifically the conversion of Langmuir/z-mode waves to electromagnetic (EM) radiation. The primary focus is the calculation of the energy and power conversion efficiencies for LMC as functions of the angle of incidence {theta} of the Langmuir/z-mode wave, temperature {beta}=T{sub e}/m{sub e}c{sup 2}, adiabatic index {gamma}, and orientation angle {phi} between the ambient density gradient {nabla}N{sub 0} and ambient magnetic field B{sub 0} in a warm, unmagnetized plasma. The ratio of these efficiencies is found to agree well as a function of {theta}, {gamma}, and {beta} with an analytical relation that depends on the group speeds of the Langmuir/z and EM wave modes. The results demonstrate that the energy conversion efficiency {epsilon} is strongly dependent on {gamma}{beta}, {phi} and {theta}, with {epsilon}{proportional_to}({gamma}{beta}){sup 1/2} and {theta}{proportional_to}({gamma}{beta}){sup 1/2}. The power conversion efficiency {epsilon}{sub p}, on the other hand, is independent of {gamma}{beta} but does vary significantly with {theta} and {phi}. The efficiencies are shown to be maximum for approximately perpendicular density gradients ({phi} Almost-Equal-To 90 Degree-Sign ) and minimal for parallel orientation ({phi}=0 Degree-Sign ) and both the energy and power conversion efficiencies peak at the same {theta}.
Tunability enhanced electromagnetic wiggler
Schlueter, Ross D. (Albany, CA); Deis, Gary A. (Livermore, CA)
1992-01-01T23:59:59.000Z
The invention discloses a wiggler used in synchrotron radiation sources and free electron lasers, where each pole is surrounded by at least two electromagnetic coils. The electromagnetic coils are energized with different amounts of current to provide a wide tunable range of the on-axis magnetic flux density, while preventing magnetic saturation of the poles.
Ben-Zion, Yehuda
Assessment of P and S wave energy radiated from very small shear-tensile seismic events in a deep. Citation: Kwiatek, G., and Y. Ben-Zion (2013), Assessment of P and S wave energy radiated from very small of radiated seismic energy in S and P phases and derive ratios of S-to-P radiated energy (ES/EP) of 539
Florida, University of
discharge, lightning electromagnetic (EM) pulse, trav- eling wave, wave reflections. I. INTRODUCTION466 IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 51, NO. 3, AUGUST 2009 Electromagnetic Pulses Produced by Bouncing-Wave-Type Lightning Discharges Amitabh Nag, Member, IEEE, and Vladimir A
Spin effect on parametric interactions of waves in magnetoplasmas
Shahid, M. [Department of Physics, Government College University, Lahore-54000 (Pakistan); Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan); Melrose, D. B. [School of Physics, University of Sydney, New South Wales 2006 (Australia); Jamil, M. [Department of Physics, Government College University, Faisalabad-38000 (Pakistan); Murtaza, G. [Salam Chair in Physics, Government College University, Lahore-54000 (Pakistan)
2012-11-15T23:59:59.000Z
The parametric decay instability of upper hybrid wave into low-frequency electromagnetic Shear Alfven wave and Ordinary mode radiation (O-mode) has been investigated in an electron-ion plasma immersed in the uniform external magnetic field. Incorporating quantum effect due to electron spin, the fluid model has been used to investigate the linear and nonlinear response of the plasma species for three-wave coupling in a magnetoplasma. It is shown that the spin of electrons has considerable effect on the parametric decay of upper hybrid wave into Ordinary mode radiation (O-mode) and Shear Alfven wave even in classical regime.
Transverse electromagnetic horn antenna with resistively-loaded exterior surfaces
Aurand, John F. (Edgewood, NM)
1999-01-01T23:59:59.000Z
An improved transverse electromagnetic (TEM) horn antenna comprises a resistive loading material on the exterior surfaces of the antenna plates. The resistive loading material attenuates or inhibits currents on the exterior surfaces of the TEM horn antenna. The exterior electromagnetic fields are of opposite polarity in comparison to the primary and desired interior electromagnetic field, thus inherently cause partial cancellation of the interior wave upon radiation or upon reception. Reducing the exterior fields increases the radiation efficiency of the antenna by reducing the cancellation of the primary interior field (supported by the interior surface currents). This increases the transmit gain and receive sensitivity of the TEM horn antenna, as well as improving the transient (time-domain) response.
Experimental determination of radiated internal wave power without pressure field data
Lee, Frank M.; Morrison, P. J. [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department and Institute for Fusion Studies, The University of Texas at Austin, Austin, Texas 78712–1192 (United States); Paoletti, M. S.; Swinney, Harry L. [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)] [Physics Department, The University of Texas at Austin, Austin, Texas 78712–1192 (United States)
2014-04-15T23:59:59.000Z
We present a method to determine, using only velocity field data, the time-averaged energy flux (J) and total radiated power P for two-dimensional internal gravity waves. Both (J) and P are determined from expressions involving only a scalar function, the stream function ?. We test the method using data from a direct numerical simulation for tidal flow of a stratified fluid past a knife edge. The results for the radiated internal wave power given by the stream function method agree to within 0.5% with results obtained using pressure and velocity data from the numerical simulation. The results for the radiated power computed from the stream function agree well with power computed from the velocity and pressure if the starting point for the stream function computation is on a solid boundary, but if a boundary point is not available, care must be taken to choose an appropriate starting point. We also test the stream function method by applying it to laboratory data for tidal flow past a knife edge, and the results are found to agree with the direct numerical simulation. The supplementary material includes a Matlab code with a graphical user interface that can be used to compute the energy flux and power from two-dimensional velocity field data.
Paris-Sud XI, Université de
Communications Commission (FCC) for wireless communications and automotive radar [14]. The 77-GHz band has been transceivers for communication and radar systems at millimeter-wave frequencies. 1. INTRODUCTION Using on their applications. There are several frequency bands in the mm-wave range which have been approved by the Federal
Lior M. Burko; Thomas W. Baumgarte; Christopher Beetle
2005-11-18T23:59:59.000Z
Beetle and Burko recently introduced a background--independent scalar curvature invariant for general relativity that carries information only about the gravitational radiation in generic spacetimes, in cases where such radiation is incontrovertibly defined. In this paper we adopt a formalism that only uses spatial data as they are used in numerical relativity and compute the Beetle--Burko radiation scalar for a number of analytical examples, specifically linearized Einstein--Rosen cylindrical waves, linearized quadrupole waves, the Kerr spacetime, Bowen--York initial data, and the Kasner spacetime. These examples illustrate how the Beetle--Burko radiation scalar can be used to examine the gravitational wave content of numerically generated spacetimes, and how it may provide a useful diagnostic for initial data sets.
Scattering of particles by radiation fields: a comparative analysis
Donato Bini; Andrea Geralico; Maria Haney; Robert T. Jantzen
2014-08-22T23:59:59.000Z
The features of the scattering of massive neutral particles propagating in the field of a gravitational plane wave are compared with those characterizing their interaction with an electromagnetic radiation field. The motion is geodesic in the former case, whereas in the case of an electromagnetic pulse it is accelerated by the radiation field filling the associated spacetime region. The interaction with the radiation field is modeled by a force term entering the equations of motion proportional to the 4-momentum density of radiation observed in the particle's rest frame. The corresponding classical scattering cross sections are evaluated too.
On the conversion of blast wave energy into radiation in active galactic nuclei and gamma-ray bursts
Martin Pohl; Reinhard Schlickeiser
1999-11-24T23:59:59.000Z
It has been suggested that relativistic blast waves may power the jets of AGN and gamma-ray bursts (GRB). We address the important issue how the kinetic energy of collimated blast waves is converted into radiation. It is shown that swept-up ambient matter is quickly isotropised in the blast wave frame by a relativistic two-stream instability, which provides relativistic particles in the jet without invoking any acceleration process. The fate of the blast wave and the spectral evolution of the emission of the energetic particles is therefore solely determined by the initial conditions. We compare our model with existing multiwavelength data of AGN and find remarkable agreement.
R. Y. Chiao; W. J. Fitelson; A. D. Speliotopoulos
2003-04-07T23:59:59.000Z
A minimal coupling rule for the coupling of the electron spin to curved spacetime in general relativity suggests the possibility of a coupling between electromagnetic and gravitational radiation mediated by means of a quantum fluid. Thus quantum transducers between these two kinds of radiation fields might exist. We report here on the first attempt at a Hertz-type experiment, in which a high-$\\rm{T_c}$ superconductor (YBCO) was the sample material used as a possible quantum transducer to convert EM into GR microwaves, and a second piece of YBCO in a separate apparatus was used to back-convert GR into EM microwaves. An upper limit on the conversion efficiency of YBCO was measured to be $1.6\\times10^{-5}$ at liquid nitrogen temperature.
Ming LI
2007-12-01T23:59:59.000Z
In this dissertation, a set of numerical simulation tools are developed under previous work to efficiently and accurately study one-dimensional (1D), two-dimensional(2D), 2D slab and three-dimensional (3D) photonic crystal structures and their defects effects by means of spectrum (transmission, reflection, absorption), band structure (dispersion relation), and electric and/or magnetic fields distribution (mode profiles). Furthermore, the lasing property and spontaneous emission behaviors are studied when active gain materials are presented in the photonic crystal structures. Various physical properties such as resonant cavity quality factor, waveguide loss, propagation group velocity of electromagnetic wave and light-current curve (for lasing devices) can be obtained from the developed software package.
Generation of terahertz radiation from a low-density plasma slab irradiated by a laser pulse
Frolov, A. A. [Russian Academy of Sciences, Joint Institute for High Temperatures (Russian Federation)
2010-04-15T23:59:59.000Z
The generation of terahertz electromagnetic radiation when a laser pulse propagates through a low-density plasma slab is considered. It is shown that terahertz waves are excited because of the growth of a weakly damped, antisymmetric leaking mode of the plasma slab. The spectral, angular, and energy parameters of the terahertz radiation are investigated, as well as the spatiotemporal structure of the emitted waves. It is demonstrated that terahertz electromagnetic wave fields are generated most efficiently when the pulse length is comparable to the slab thickness.
Scattering of radiation in collisionless dusty plasmas
Tolias, P.; Ratynskaia, S. [Space and Plasma Physics, Royal Institute of Technology, Stockholm SE-100 44 (Sweden)
2013-04-15T23:59:59.000Z
Scattering of electromagnetic waves in collisionless dusty plasmas is studied in the framework of a multi-component kinetic model. The investigation focuses on the spectral distribution of the scattered radiation. Pronounced dust signatures are identified in the coherent spectrum due to scattering from the shielding cloud around the dust grains, dust acoustic waves, and dust-ion acoustic waves. The magnitude and shape of the scattered signal near these spectral regions are determined with the aid of analytical expressions and its dependence on the dust parameters is investigated. The use of radiation scattering as a potential diagnostic tool for dust detection is discussed.
Radiation from a $D$-dimensional collision of gravitational shock waves
Flávio S. Coelho
2015-05-08T23:59:59.000Z
Classically, if two highly boosted particles collide head-on, a black hole is expected to form whose mass may be inferred from the gravitational radiation emitted during the collision. If this occurs at trans-Planckian energies, it should be well described by general relativity. Furthermore, if there exist hidden extra dimensions, the fundamental Planck mass may well be of the order of the TeV and thus achievable with current or future particle accelerators. By modeling the colliding particles as Aichelburg-Sexl shock waves on a flat, $D$-dimensional background, we devise a perturbative framework to compute the space-time metric in the future of the collision. Then, a generalisation of Bondi's formalism is employed to extract the gravitational radiation and compute the inelasticity of the collision: the percentage of the initial centre-of-mass energy that is radiated away. Using the axial symmetry of the problem, we show that this information is encoded in a single function of the transverse metric components - the news function. We then unveil a hidden conformal symmetry which exists at each order in perturbation theory and thus makes the problem effectively two-dimensional. Moreover, it allows for the factorisation of the angular dependence of the news function, i.e. the radiation pattern at null infinity, and clarifies the correspondence between the perturbative series of the metric and an angular expansion off the collision axis. The first-order estimate, or isotropic term, is computed analytically and yields a remarkable simple formula for the inelasticity for any $D$. Higher-order terms, however, require the use of a computer for numerical integration. We study the integration domain and compute, numerically, the Green's functions and the sources, thus paving the way for the computation of the inelasticity in a future work.
Geddes, Cameron Guy Robinson
fields or materials, they emit radiation at frequencies ranging from microwaves to gamma rays. A new magnets--the e beam generates subpicosecond bursts of coherent 8-keV x rays (see PHYSICS TODAY, May 2005 be delivering x-ray beams of unprece- dented peak brightness, orders of magnitude greater than one gets from
Search for periodic gravitational radiation with the ALLEGRO gravitational wave detector
E. Mauceli; M. P. McHugh; W. O. Hamilton; W. W. Johnson; A. Morse
2000-07-11T23:59:59.000Z
We describe the search for a continuous signal of gravitational radiation from a rotating neutron star in the data taken by the ALLEGRO gravitational wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1 kHz, only neutron stars with spin periods near 2 ms are potential sources. There are no known sources of this typ e for ALLEGRO, so we directed the search towards both the galactic center and the globular clus ter 47 Tucanae. The analysis puts a constraint of roughly $8 \\times 10^{-24}$ at frequencies near 1 kHz on the gravitational strain emitted from pulsar spin-down in either 47 Tucanae or the galactic center.
Search for periodic gravitational radiation with the ALLEGRO gravitational wave detector
Mauceli, E; Hamilton, W O; Johnson, W W; Morse, A
2002-01-01T23:59:59.000Z
We describe the search for a continuous signal of gravitational radiation from a rotating neutron star in the data taken by the ALLEGRO gravitational wave detector in early 1994. Since ALLEGRO is sensitive at frequencies near 1 kHz, only neutron stars with spin periods near 2 ms are potential sources. There are no known sources of this typ e for ALLEGRO, so we directed the search towards both the galactic center and the globular clus ter 47 Tucanae. The analysis puts a constraint of roughly $8 \\times 10^{-24}$ at frequencies near 1 kHz on the gravitational strain emitted from pulsar spin-down in either 47 Tucanae or the galactic center.
State-Space Realization of the Wave-Radiation Force within FAST: Preprint
Duarte, T.; Sarmento, A.; Alves, M.; Jonkman, J.
2013-06-01T23:59:59.000Z
Several methods have been proposed in the literature to find a state-space model for the wave-radiation forces. In this paper, four methods were compared, two in the frequency domain and two in the time domain. The frequency-response function and the impulse response of the resulting state-space models were compared against the ones derived by the numerical code WAMIT. The implementation of the state-space module within the FAST offshore wind turbine computer-aided engineering (CAE) tool was verified, comparing the results against the previously implemented numerical convolution method. The results agreed between the two methods, with a significant reduction in required computational time when using the state-space module.
Julius Vanko; Miroslav Sukenik; Jozef Sima
2007-05-29T23:59:59.000Z
Including Vaidya metric into the model of Expansive Nondecelerative Universe allows to localize the energy of gravitational field. A term of effective gravitational range is introduced and classic Newton potential is substituted for Yukawa-type potential. It allows to allocate a typical frequency value to each gravitational field. Derived theoretical conclusions led us to investigate the effect of electromagnetic field with a precisely predetermined frequency and intensity on iron. We believe that under certain circumstances a decrease in iron gravitational mass should be observed. Two model experiments verifying the theoretical conclusions are proposed.
Cellular Manipulation and Control by Electromagnetism | Argonne...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
phenomenon for sensors; however, one may also use intense electromagnetic radiation, such as pulsed power, plasmas, or lasers, to induce changes in cellular...
E. Garcia-Berro; P. Loren-Aguilar; A. H. Corsico; L. G. Althaus; J. A. Lobo; J. Isern
2005-09-13T23:59:59.000Z
We compute the emission of gravitational radiation from pulsating white dwarfs. This is done by using an up-to-date stellar evolutionary code coupled with a state-of-the-art pulsational code. The emission of gravitational waves is computed for a standard 0.6 solar masses white dwarf with a liquid carbon-oxygen core and a hydrogen-rich envelope, for a massive DA white dwarf with a partially crystallized core for which various l=2 modes have been observed (BPM 37093) and for PG 1159-035, the prototype of the GW Vir class of variable stars, for which several quadrupole modes have been observed as well. We find that these stars do not radiate sizeable amounts of gravitational waves through their observed pulsation g-modes, in line with previous studies. We also explore the possibility of detecting gravitational waves radiated by the f-mode and the p-modes. We find that in this case the gravitational wave signal is very large and, hence, the modes decay very rapidly. We also discuss the possible implications of our calculations for the detection of gravitational waves from pulsating white dwarfs within the framework of future space-borne interferometers like LISA.
Mead, Carver
2015-01-01T23:59:59.000Z
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...
Kepler, Grace Martinelli
Reduced Order Computational Methods for Electromagnetic Material Interrogation Using Pulsed Signals of a pulsed planar electromagnetic wave of a dielectric slab with a supraconductive backing. Previous work
Bulanov, S. V. [QuBS, Japan Atomic Energy Agency, Kizugawa, Kyoto, 619-0215 (Japan); A. M. Prokhorov Institute of General Physics RAS, Moscow, 119991 (Russian Federation); Esirkepov, T. Zh.; Kando, M. [QuBS, Japan Atomic Energy Agency, Kizugawa, Kyoto, 619-0215 (Japan); Pegoraro, F. [Physical Department, University of Pisa, Pisa 56127 (Italy); Bulanov, S. S. [University of California, Berkeley, California 94720 (United States); Geddes, C. G. R.; Schroeder, C. B.; Esarey, E. [Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States); Leemans, W. P. [University of California, Berkeley, California 94720 (United States); Lawrence Berkeley National Laboratory, Berkeley, California, 94720 (United States)
2012-10-15T23:59:59.000Z
When ions are accelerated by the radiation pressure of a laser pulse, their velocity cannot exceed the pulse group velocity which can be considerably smaller than the speed of light in vacuum. This is demonstrated in two cases corresponding to a thin foil target irradiated by high intensity laser light and to the hole boring produced in an extended plasma by the laser pulse. It is found that the beams of accelerated ions are unstable against Buneman-like and Weibel-like instabilities which results in the broadening of the ion energy spectrum.
Electromagnetic effects on geodesic acoustic modes
Bashir, M. F., E-mail: frazbashir@yahoo.com [Salam Chair in Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Department of Physics, G. C. University Lahore, Katchery Road, Lahore 54000 (Pakistan); Smolyakov, A. I. [University of Saskatchewan, 116 Science Place, Saskatoon S7N 5E2 (Canada); Institute of Tokamak Physics, NRC “Kurchatov Institute,” 123182 Moscow (Russian Federation); Elfimov, A. G. [Institute of Physics, University of São Paulo, São Paulo 05508-090 (Brazil); Melnikov, A. V. [Institute of Tokamak Physics, NRC “Kurchatov Institute,” 123182 Moscow (Russian Federation); National Research Nuclear University MEPhI, 115409, Moscow (Russian Federation); Murtaza, G. [Visiting Professor, Department of Physics, Quaid-e-Azam University, Islamabad (Pakistan)
2014-08-15T23:59:59.000Z
By using the full electromagnetic drift kinetic equations for electrons and ions, the general dispersion relation for geodesic acoustic modes (GAMs) is derived incorporating the electromagnetic effects. It is shown that m?=?1 harmonic of the GAM mode has a finite electromagnetic component. The electromagnetic corrections appear for finite values of the radial wave numbers and modify the GAM frequency. The effects of plasma pressure ?{sub e}, the safety factor q, and the temperature ratio ? on GAM dispersion are analyzed.
Mauricio Cataldo; Alberto A. García
2014-05-15T23:59:59.000Z
In this paper we discuss the radiation equation of state $p=\\rho/2$ in (2+1)-dimensions. In (3+1)-dimensions the equation of state $p=\\rho/3$ may be used to describe either actual electromagnetic radiation (photons) as well as a gas of massless particles in a thermodynamic equilibrium (for example neutrinos). In this work it is shown that in the framework of (2+1)-dimensional Maxwell electrodynamics the radiation law $p=\\rho/2$ takes place only for plane waves, i.e. for $E = B$. Instead of the linear Maxwell electrodynamics, to derive the (2+1)-radiation law for more general cases with $E \
Mitri, F.G., E-mail: mitri@chevron.com
2014-03-15T23:59:59.000Z
The axial and transverse radiation forces on a fluid sphere placed arbitrarily in the acoustical field of Bessel beams of standing waves are evaluated. The three-dimensional components of the time-averaged force are expressed in terms of the beam-shape coefficients of the incident field and the scattering coefficients of the fluid sphere using a partial-wave expansion (PWE) method. Examples are chosen for which the standing wave field is composed of either a zero-order (non-vortex) Bessel beam, or a first-order Bessel vortex beam. It is shown here, that both transverse and axial forces can push or pull the fluid sphere to an equilibrium position depending on the chosen size parameter ka (where k is the wave-number and a the sphere’s radius). The corresponding results are of particular importance in biophysical applications for the design of lab-on-chip devices operating with Bessel beams standing wave tweezers. Moreover, potential investigations in acoustic levitation and related applications in particle rotation in a vortex beam may benefit from the results of this study. -- Highlights: •The axial and transverse forces on a fluid sphere in acoustical Bessel beams tweezers are evaluated. •The attraction or repulsion to an equilibrium position in the standing wave field is examined. •Potential applications are in particle manipulation using standing waves.
Allen, Jont
), Stockholm 70, Sweden Summary The relation between axially symmetric plane waves in a cylindrical duct-wave is of all-pass nature, but there are high-pass cut-off frequencies for p-waves etc. A modified "Webster of higher order, assuming the wave fronts to be curved with area 8(z) while gas density and bulk modulus
Connecting Numerical Relativity and Data Analysis of Gravitational Wave Detectors
Shoemaker, Deirdre; London, Lionel; Pekowsky, Larne
2015-01-01T23:59:59.000Z
Gravitational waves deliver information in exquisite detail about astrophysical phenomena, among them the collision of two black holes, a system completely invisible to the eyes of electromagnetic telescopes. Models that predict gravitational wave signals from likely sources are crucial for the success of this endeavor. Modeling binary black hole sources of gravitational radiation requires solving the Eintein equations of General Relativity using powerful computer hardware and sophisticated numerical algorithms. This proceeding presents where we are in understanding ground-based gravitational waves resulting from the merger of black holes and the implications of these sources for the advent of gravitational-wave astronomy.
LaCure, Mari Mae
2010-04-29T23:59:59.000Z
Waves is the supporting document to the Master of Fine Arts thesis exhibition of the same title. Exhibited March 7-12 2010 in the Art and Design Gallery at the University of Kansas, Waves was comprised of a series of mixed media drawings...
anomalous spin waves: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
branches of wave dispersion: spin-electromagnetic plasma waves and self-consistent spin waves. Propagation of neutron beams through quantum plasmas is also considered....
Journal of Sound and Vibration 298 (2006) 108131 Elastic wave radiation from a high frequency
Abrahams, I. David
JOURNAL OF SOUND AND VIBRATION Journal of Sound and Vibration 298 (2006) 108Â131 Elastic wave. Introduction Problems concerning the propagation, refraction and diffraction of waves are the subject method to detect defects is to analyse the scattering of the elastic waves generated by ultrasonic
Telle, J.M.
1984-05-01T23:59:59.000Z
Apparatus and method for generating continuous wave 16 ..mu..m laser radiation using gaseous CF/sub 4/. Laser radiation at 16 ..mu..m has been observed in a cooled static cell containing low pressure CF/sub 4/ optically pumped by an approximately 3 W output power c-w CO/sub 2/ laser. The laser cavity employed was a multiple-pass off-axis-path two spherical mirror ring resonator. Unidirectional CF/sub 4/ laser output power at 615 cm/sup -1/ exceeded 2 mW. Computer calculations indicate that for modest pump powers of about 40 W, approximately 1 W of emitted laser radiation at 16 ..mu..m might be obtained.
Apparatus and method for generating continuous wave 16 .mu.m laser radiation using gaseous CF.sub.4
Telle, John M. (Los Alamos, NM)
1986-01-01T23:59:59.000Z
Apparatus and method for generating continuous wave 16 .mu.m laser radiation using gaseous CF.sub.4. Laser radiation at 16 .mu.m has been observed in a cooled static cell containing low pressure CF.sub.4 optically pumped by an approximately 3 W output power cw CO.sub.2 laser. The laser cavity employed was a multiple-pass off-axis-path two spherical mirror ring resonator. Unidirectional CF.sub.4 laser output power at 615 cm.sup.-1 exceeded 2 mW. Computer calculations indicate that for modest pump powers of about 40 W, approximately 1 W of emitted laser radiation at 16 .mu.m might be obtained.
Proposed observations of gravity waves from the early Universe via "Millikan oil drops"
R. Y. Chiao
2006-06-29T23:59:59.000Z
Pairs of Planck-mass drops of superfluid helium coated by electrons (i.e., ``Millikan oil drops''), when levitated in a superconducting magnetic trap, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. This leads to the possibility of a Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves. Detection of the gravity-wave analog of the cosmic microwave background using these drops can discriminate between various theories of the early Universe.
New directions for gravity-wave physics via "Millikan oil drops"
Raymond Y. Chiao
2007-04-06T23:59:59.000Z
Pairs of Planck-mass--scale drops of superfluid helium coated by electrons (i.e., "Millikan oil drops"), when levitated in the presence of strong magnetic fields and at low temperatures, can be efficient quantum transducers between electromagnetic (EM) and gravitational (GR) radiation. A Hertz-like experiment, in which EM waves are converted at the source into GR waves, and then back-converted at the receiver from GR waves back into EM waves, should be practical to perform. This would open up observations of the gravity-wave analog of the CMB from the extremely early Big Bang, and also communications directly through the interior of the Earth.
Modeling the comfort effects of short-wave solar radiation indoors
Arens, Edward; Hoyt, Tyler; Zhou, Xin; Huang, Li; Zhang, Hui; Schiavon, Stefano
2015-01-01T23:59:59.000Z
2004. [3] Blum HF. Solar heat load, its relationship to theS, Parsons K. The effects of solar radiation on thermalParsons K. The effects of solar radiation and black body re-
Silicon-based optical leaky wave antenna with narrow beam radiation
Song, Qi; Campione, Salvatore; Boyraz, Ozdal; Capolino, Filippo
2011-01-01T23:59:59.000Z
achievable in the electric far-field radiation magnitude inelectric far-field along the direction ? max of maximum radiationelectric field along the aperture. 4.3 Far-field radiation
Crane, Randolph W.; Marts, Donna J.
1994-11-01T23:59:59.000Z
An electromagnetic fastener for manipulating objects in space uses the matic attraction of various metals. An end effector is attached to a robotic manipulating system having an electromagnet such that when current is supplied to the electromagnet, the object is drawn and affixed to the end effector, and when the current is withheld, the object is released. The object to be manipulated includes a multiplicity of ferromagnetic patches at various locations to provide multiple areas for the effector on the manipulator to become affixed to the object. The ferromagnetic patches are sized relative to the object's geometry and mass.
Crane, Randolph W. (Idaho Falls, ID); Marts, Donna J. (Idaho Falls, ID)
1994-01-01T23:59:59.000Z
An electromagnetic fastener for manipulating objects in space uses the matic attraction of various metals. An end effector is attached to a robotic manipulating system having an electromagnet such that when current is supplied to the electromagnet, the object is drawn and affixed to the end effector, and when the current is withheld, the object is released. The object to be manipulated includes a multiplicity of ferromagnetic patches at various locations to provide multiple areas for the effector on the manipulator to become affixed to the object. The ferromagnetic patches are sized relative to the object's geometry and mass.
Allan, Richard P.
Environment Model (HiGEM), suggest that including mineral dust radiative effects removes this bias21 June 2007, although differences in cloud cover also impact the modelGERB differences. Copyright c 2011 A Examination of long-wave radiative bias in general circulation models over North Africa during
Ma, Po-Lun; Zhang, Kai; Shi, Jainn Jong; Matsui, Toshihisa; Arking, Albert
2012-12-19T23:59:59.000Z
Episodic events of both Saharan dust outbreaks and African easterly waves (AEWs) are observed to move westward over the eastern tropical Atlantic Ocean. The relationship between the warm, dry, and dusty Saharan air layer on the nearby storms has been the subject of considerable debate. In this study, the Weather Research and Forecasting model is used to investigate the radiative effect of dust on the development of AEWs during August and September, the months of maximumtropical cyclone activity, in years 2003–07. The simulations show that dust radiative forcing enhances the convective instability of the environment. As a result, mostAEWsintensify in the presence of a dust layer. The Lorenz energy cycle analysis reveals that the dust radiative forcing enhances the condensational heating, which elevates the zonal and eddy available potential energy. In turn, available potential energy is effectively converted to eddy kinetic energy, in which local convective overturning plays the primary role. The magnitude of the intensification effect depends on the initial environmental conditions, including moisture, baroclinity, and the depth of the boundary layer. The authors conclude that dust radiative forcing, albeit small, serves as a catalyst to promote local convection that facilitates AEW development.
Radiation reaction in quantum field theory
Higuchi, A
2002-01-01T23:59:59.000Z
We investigate radiation-reaction effects for a charged scalar particle accelerated by an external potential realized as a space-dependent mass term in quantum electrodynamics. In particular, we calculate the position shift of the final-state wave packet of the charged particle due to radiation at lowest order in the fine structure constant alpha and in the small h-bar approximation. This quantity turns out to be much smaller than the width of the wave packet but can be compared with the classical counterpart. We show that it disagrees with the result obtained using the Abraham-Lorentz-Dirac formula for the radiation-reaction force, and that it agrees with the classical theory if one assumes that the particle loses its energy to radiation at each moment of time according to the Larmor formula in the static frame of the potential. We also point out that the electromagnetic correction to the potential has no classical limit.
Whistler wave generation by non-gyrotropic, relativistic, electron beams
Skender, M.; Tsiklauri, D. [School of Physics and Astronomy, Queen Mary University of London, 327 Mile End Road, London E1 4NS (United Kingdom)] [School of Physics and Astronomy, Queen Mary University of London, 327 Mile End Road, London E1 4NS (United Kingdom)
2014-04-15T23:59:59.000Z
Particle-in-cell code, EPOCH, is used for studying features of the wave component evident to propagate backwards from the front of the non-gyrotropic, relativistic beam of electrons injected in the Maxwellian, magnetised background plasma with decreasing density profile. According to recent findings presented in Tsiklauri [Phys. Plasmas 18, 052903 (2011)], Schmitz and Tsiklauri [Phys. Plasmas 20, 062903 (2013)], and Pechhacker and Tsiklauri [Phys. Plasmas 19, 112903 (2012)], in a 1.5-dimensional magnetised plasma system, the non-gyrotropic beam generates freely escaping electromagnetic radiation with properties similar to the Type-III solar radio bursts. In this study, the backwards propagating wave component evident in the perpendicular components of the electromagnetic field in such a system is presented for the first time. Background magnetic field strength in the system is varied in order to prove that the backwards propagating wave's frequency, prescribed by the whistler wave dispersion relation, is proportional to the specified magnetic field. Moreover, the identified whistlers are shown to be generated by the normal Doppler-shifted relativistic resonance. Large fraction of the energy of the perpendicular electromagnetic field components is found to be carried away by the whistler waves, while a small but sufficient fraction is going into L- and R-electromagnetic modes.
acoustic-radiation-force-driven shear wave: Topics by E-print...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
3; , H. Tran y , S. Wynne z December 14, 2001 Abstract We consider a nonlinear model for propagation of shear waves in viscoelastic examine the well-posedness of a one-dimensional...
RADIATIVE HEATING OF THE SOLAR CORONA
Moran, Thomas G., E-mail: moran@grace.nascom.nasa.gov [Physics Department, Catholic University of America, 200 Hannan Hall, Washington, DC 20064 (United States) and NASA/GSFC, Code 671, Greenbelt, MD 20771 (United States)
2011-10-20T23:59:59.000Z
We investigate the effect of solar visible and infrared radiation on electrons in the Sun's atmosphere using a Monte Carlo simulation of the wave-particle interaction and conclude that sunlight provides at least 40% and possibly all of the power required to heat the corona, with the exception of dense magnetic flux loops. The simulation uses a radiation waveform comprising 100 frequency components spanning the solar blackbody spectrum. Coronal electrons are heated in a stochastic manner by low coherence solar electromagnetic radiation. The wave 'coherence time' and 'coherence volume' for each component is determined from optical theory. The low coherence of solar radiation allows moving electrons to gain energy from the chaotic wave field which imparts multiple random velocity 'kicks' to these particles causing their velocity distribution to broaden or heat. Monte Carlo simulations of broadband solar radiative heating on ensembles of 1000 electrons show heating at per particle levels of 4.0 x 10{sup -21} to 4.0 x 10{sup -20} W, as compared with non-loop radiative loss rates of {approx}1 x 10{sup -20} W per electron. Since radiative losses comprise nearly all of the power losses in the corona, sunlight alone can explain the elevated temperatures in this region. The volume electron heating rate is proportional to density, and protons are assumed to be heated either by plasma waves or through collisions with electrons.
Gan, Li, E-mail: ligan0001@gmail.com; Mousen, Cheng; Xiaokang, Li [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)] [College of Aerospace Science and Engineering, National University of Defense Technology, Changsha (China)
2014-03-15T23:59:59.000Z
In the laser intensity range that the laser supported detonation (LSD) wave can be maintained, dissociation, ionization and radiation take a substantial part of the incidence laser energy. There is little treatment on the phenomenon in the existing models, which brings obvious discrepancies between their predictions and the experiment results. Taking into account the impact of dissociation, ionization and radiation in the conservations of mass, momentum and energy, a modified LSD wave model is developed which fits the experimental data more effectively rather than the existing models. Taking into consideration the pressure decay of the normal and the radial rarefaction, the laser induced impulse that is delivered to the target surface is calculated in the air; and the dependencies of impulse performance on laser intensity, pulse width, ambient pressure and spot size are indicated. The results confirm that the dissociation is the pivotal factor of the appearance of the momentum coupling coefficient extremum. This study focuses on a more thorough understanding of LSD and the interaction between laser and matter.
Electrical wire insulation and electromagnetic coil
Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)
1984-01-01T23:59:59.000Z
An electromagnetic coil for high temperature and high radiation application in which glass is used to insulate the electrical wire. A process for applying the insulation to the wire is disclosed which results in improved insulation properties.
An electromagnetic black hole made of metamaterials
Cheng, Qiang
2009-01-01T23:59:59.000Z
Traditionally, a black hole is a region of space with huge gravitational field in the means of general relativity, which absorbs everything hitting it including the light. In general relativity, the presence of matter-energy densities results in the motion of matter propagating in a curved spacetime1, which is similar to the electromagnetic-wave propagation in a curved space and in an inhomogeneous metamaterial2. Hence one can simulate the black hole using electromagnetic fields and metamaterials. In a recent theoretical work, an optical black hole has been proposed based on metamaterials, in which the numerical simulations showed a highly efficient light absorption3. Here we report the first experimental demonstration of electromagnetic black hole in the microwave frequencies. The proposed black hole is composed of non-resonant and resonant metamaterial structures, which can absorb electromagnetic waves efficiently coming from all directions due to the local control of electromagnetic fields. Hence the elect...
Incorporating spectral characteristics of Pc5 waves into three-dimensional radiation belt
Elkington, Scot R.
. This is the first analysis in three dimensions utilizing model ULF wave electric and magnetic fields on the guiding losses at MeV energies. This inner electron belt resides mainly below 2 RE geocen- tric distance center trajectories of relativistic electrons. A model is developed, describing magnetic and electric
Method and apparatus for generating radiation utilizing DC to AC conversion with a conductive front
Dawson, J.M.; Mori, W.B.; Lai, C.H.; Katsouleas, T.C.
1998-07-14T23:59:59.000Z
Method and apparatus ar disclosed for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing. 4 figs.
Method and apparatus for generating radiation utilizing DC to AC conversion with a conductive front
Dawson, John M. (Pacific Palisades, CA); Mori, Warren B. (Hermosa Beach, CA); Lai, Chih-Hsiang (So. Pasadena, CA); Katsouleas, Thomas C. (Malibu, CA)
1998-01-01T23:59:59.000Z
Method and apparatus for generating radiation of high power, variable duration and broad tunability over several orders of magnitude from a laser-ionized gas-filled capacitor array. The method and apparatus convert a DC electric field pattern into a coherent electromagnetic wave train when a relativistic ionization front passes between the capacitor plates. The frequency and duration of the radiation is controlled by the gas pressure and capacitor spacing.
Aldridge, David F.
2014-11-01T23:59:59.000Z
A reciprocity theorem is an explicit mathematical relationship between two different wavefields that can exist within the same space - time configuration. Reciprocity theorems provi de the theoretical underpinning for mod ern full waveform inversion solutions, and also suggest practical strategies for speed ing up large - scale numerical modeling of geophysical datasets . In the present work, several previously - developed electromagnetic r eciprocity theorems are generalized to accommodate a broader range of medi um, source , and receiver types. Reciprocity relations enabling the interchange of various types of point sources and point receivers within a three - dimensional electromagnetic model are derived. Two numerical modeling algorithms in current use are successfully tested for adherence to reciprocity. Finally, the reciprocity theorem forms the point of departure for a lengthy derivation of electromagnetic Frechet derivatives. These mathe matical objects quantify the sensitivity of geophysical electromagnetic data to variatio ns in medium parameters, and thus constitute indispensable tools for solution of the full waveform inverse problem. ACKNOWLEDGEMENTS Sandia National Labor atories is a multi - program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the US Department of Energy's National Nuclear Security Administration under contract DE - AC04 - 94AL85000. Signif icant portions of the work reported herein were conducted under a Cooperative Research and Development Agreement (CRADA) between Sandia National Laboratories (SNL) and CARBO Ceramics Incorporated. The author acknowledges Mr. Chad Cannan and Mr. Terry Pa lisch of CARBO Ceramics, and Ms. Amy Halloran, manager of SNL's Geophysics and Atmospheric Sciences Department, for their interest in and encouragement of this work. Special thanks are due to Dr . Lewis C. Bartel ( recently retired from Sandia National Labo ratories and now a geophysical consultant ) and Dr. Chester J. Weiss (recently rejoined with Sandia National Laboratories) for many stimulating (and reciprocal!) discussions regar ding the topic at hand.
Experimental determination of radiated internal wave power without pressure field Frank M. Lee,1
Morrison, Philip J.,
= S d2 x pv Â· ^n , (1) where J = pv is the baroclinic energy flux, p is the perturbed pressure field, v to determine, using only velocity field data, the time-averaged energy flux J and total radiated power P) that can be used to compute the energy flux and power from any two-dimensional velocity field data. PACS
Degasperis, Antonio; Aceves, Alejandro B
2015-01-01T23:59:59.000Z
We derive the rogue wave solution of the classical massive Thirring model, that describes nonlinear optical pulse propagation in Bragg gratings. Combining electromagnetically induced transparency with Bragg scattering four-wave mixing, may lead to extreme waves at extremely low powers.
AIP/123-QED Experimental determination of radiated internal wave power without pressure field
Texas at Austin. University of
S is given by, P = S d2 x J Â· ^n = S d2 x pv Â· ^n , (1) where J = pv is the baroclinic energy flux, p, using only velocity field data, the time-averaged energy flux J and total radiated power P for two the energy flux and power from any two-dimensional velocity field data. PACS numbers: Valid PACS appear here
McCloy, John S.; Jordan, David V.; Kelly, James F.; McMakin, Douglas L.; Johnson, Bradley R.; Campbell, Luke W.
2009-09-01T23:59:59.000Z
A new concept for radiation detection is proposed, allowing a decoupling of the sensing medium and the readout. An electromagnetic material, such as a magnetic ceramic ferrite, is placed near a source to be tracked such as a shipping container. The electromagnetic material changes its properties, in this case its magnetic permeability, as a function of radiation. This change is evident as a change in reflection frequency and magnitude when probed using a microwave/millimeter-wave source. This brief report discusses modeling of radiation interaction of various candidate materials using a radiation detector modeling code Geant4, system design considerations for the remote readout, and some theory of the material interaction physics. The theory of radiation change in doped magnetic insulator ferrites such as yttrium iron garnet (YIG) seems well founded based on literature documentation of the photomagnetic effect. The literature also suggests sensitivity of permittivity to neutrons in some ferroelectrics. Research to date indicates that experimental demonstration of these effects in the context of radiation detection is warranted.
Guided wave radiation from a point source in the proximity of a pipe bend
Brath, A. J.; Nagy, P. B. [Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH 45221 (United States); Simonetti, F. [Department of Aerospace Engineering and Engineering Mechanics, University of Cincinnati, Cincinnati, OH 45221,USA and Cincinnati NDE, Cincinnati, OH 45244 (United States); Instanes, G. [ClampOn AS, 5162 Laksevaag, Bergen, Norway and Cincinnati NDE, Cincinnati, OH 45244 (United States)
2014-02-18T23:59:59.000Z
Throughout the oil and gas industry corrosion and erosion damage monitoring play a central role in managing asset integrity. Recently, the use of guided wave technology in conjunction with tomography techniques has provided the possibility of obtaining point-by-point maps of wall thickness loss over the entire volume of a pipeline section between two ring arrays of ultrasonic transducers. However, current research has focused on straight pipes while little work has been done on pipe bends which are also the most susceptible to developing damage. Tomography of the bend is challenging due to the complexity and computational cost of the 3-D elastic model required to accurately describe guided wave propagation. To overcome this limitation, we introduce a 2-D anisotropic inhomogeneous acoustic model which represents a generalization of the conventional unwrapping used for straight pipes. The shortest-path ray-tracing method is then applied to the 2-D model to compute ray paths and predict the arrival times of the fundamental flexural mode, A0, excited by a point source on the straight section of pipe entering the bend and detected on the opposite side. Good agreement is found between predictions and experiments performed on an 8” diameter (D) pipe with 1.5 D bend radius. The 2-D model also reveals the existence of an acoustic lensing effect which leads to a focusing phenomenon also confirmed by the experiments. The computational efficiency of the 2-D model makes it ideally suited for tomography algorithms.
Carver Mead
2015-03-16T23:59:59.000Z
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.
Probing the thermal character of analogue Hawking radiation for shallow water waves?
Florent Michel; Renaud Parentani
2014-09-15T23:59:59.000Z
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.
Study of radiative blast waves generated on the Z-beamlet laser.
Edens, Aaron D.; Schwarz, Jens
2012-02-01T23:59:59.000Z
This document describes the original goals of the project to study the Vishniac Overstability on blast waves produced using the Z-Beamlet laser facility as well as the actual results. The proposed work was to build on earlier work on the facility and result in the best characterized set of data for such phenomena in the laboratory. To accomplish the goals it was necessary to modify the existing probe laser at the facility so that it could take multiple images over the course of 1-2 microseconds. Troubles with modifying the probe laser are detailed as well as the work that went into said modifications. The probe laser modification ended up taking the entire length of the project and were the major accomplishment of the research.
Space-time Curvature of Classical Electromagnetism
R. W. M. Woodside
2004-10-08T23:59:59.000Z
The space-time curvature carried by electromagnetic fields is discovered and a new unification of geometry and electromagnetism is found. Curvature is invariant under charge reversal symmetry. Electromagnetic field equations are examined with De Rham co homology theory. Radiative electromagnetic fields must be exact and co exact to preclude unobserved massless topological charges. Weyl's conformal tensor, here called ``the gravitational field'', is decomposed into a divergence-free non-local piece with support everywhere and a local piece with the same support as the matter. By tuning a local gravitational field to a Maxwell field the electromagnetic field's local gravitational field is discovered. This gravitational field carries the electromagnetic field's polarization or phase information, unlike Maxwell's stress-energy tensor. The unification assumes Einstein's equations and derives Maxwell's equations from curvature assumptions. Gravity forbids magnetic monopoles! This unification is stronger than the Einstein-Maxwell equations alone, as those equations must produce the electromagnetic field's local gravitational field and not just any conformal tensor. Charged black holes are examples. Curvature of radiative null electromagnetic fields is characterized.
Electromagnetic time reversal algorithms and source localization in lossy dielectric media
Abdul Wahab; Amer Rasheed; Tasawar Hayat; Rab Nawaz
2014-09-16T23:59:59.000Z
The problem of reconstructing the spatial support of an extended radiating electric current source density in a lossy dielectric medium from transient boundary measurements of the electric fields is studied. A time reversal algorithm is proposed to localize a source density from loss-less wave-field measurements. Further, in order to recover source densities in a lossy medium, we first build attenuation operators thereby relating loss-less waves with lossy ones. Then based on asymptotic expansions of attenuation operators with respect to attenuation parameter, we propose two time reversal strategies for localization. The losses in electromagnetic wave propagation are incorporated using the Debye's complex permittivity, which is well-adopted for low frequencies (radio and microwave) associated with polarization in dielectrics.
Guan, W; Sotome, M; Kinoshita, Y; Takeda, R; Inoue, A; Horiuchi, S; Okamoto, H
2014-01-01T23:59:59.000Z
Terahertz radiation by optical rectification has been observed at room temperature in a hydrogen-bonded organic molecular ferroelectric crystal, 2-phenyl malondialdehyde (PhMDA). The radiated electromagnetic wave consisted of a single-cycle terahertz pulse with a temporal width of $\\sim$ 0.5 ps. The terahertz radiation amplitude divided by the sample thickness in PhMDA was nearly equivalent to that in a typical terahertz wave emitter ZnTe. This is attributable to a long coherence length in the range of 130 $\\sim$ 800 $\\mu$m for the terahertz radiation from PhMDA. We also discussed the possibility of PhMDA as a terahertz wave emitter in terms of the phase-matching condition.
Energy Innovation Portal (Marketing Summaries) [EERE]
2013-04-15T23:59:59.000Z
Security threats come in many forms—airborne, radiative, gaseous, human, or infiltrative—and it can be costly and impractical to deploy a broad suite of detector technologies to identify all potential hazards in public places. Argonne’s millimeter wave (mmW) sensor technologies measure a wide range of threat materials remotely, making them well suited to many security, industrial and medical applications....
Louchev, Oleg A.; Saito, Norihito; Wada, Satoshi [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Bakule, Pavel [STFC, ISIS Facility, Rutherford Appleton Laboratory, Chilton, Oxfordshire OX11 0QX (United Kingdom); Yokoyama, Koji [Advanced Science Institute, RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198 (Japan); Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan); Ishida, Katsuhiko; Iwasaki, Masahiko [Advanced Meson Science Laboratory, RIKEN Nishina Center, RIKEN, Wako, Saitama 351-0198 (Japan)
2011-09-15T23:59:59.000Z
We present a theoretical model combined with a computational study of a laser four-wave mixing process under optical discharge in which the non-steady-state four-wave amplitude equations are integrated with the kinetic equations of initial optical discharge and electron avalanche ionization in Kr-Ar gas. The model is validated by earlier experimental data showing strong inhibition of the generation of pulsed, tunable Lyman-{alpha} (Ly-{alpha}) radiation when using sum-difference frequency mixing of 212.6 nm and tunable infrared radiation (820-850 nm). The rigorous computational approach to the problem reveals the possibility and mechanism of strong auto-oscillations in sum-difference resonant Ly-{alpha} generation due to the combined effect of (i) 212.6-nm (2+1)-photon ionization producing initial electrons, followed by (ii) the electron avalanche dominated by 843-nm radiation, and (iii) the final breakdown of the phase matching condition. The model shows that the final efficiency of Ly-{alpha} radiation generation can achieve a value of {approx}5x10{sup -4} which is restricted by the total combined absorption of the fundamental and generated radiation.
Scanning evanescent electro-magnetic microscope
Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Anhui, CN); Schultz, Peter G. (La Jolla, CA); Wei, Tao (Sunnyvale, CA)
2003-01-01T23:59:59.000Z
A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.
Scanning evanescent electro-magnetic microscope
Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)
2001-01-01T23:59:59.000Z
A novel scanning microscope is described that uses near-field evanescent electromagnetic waves to probe sample properties. The novel microscope is capable of high resolution imaging and quantitative measurements of the electrical properties of the sample. The inventive scanning evanescent wave electromagnetic microscope (SEMM) can map dielectric constant, tangent loss, conductivity, complex electrical impedance, and other electrical parameters of materials. The quantitative map corresponds to the imaged detail. The novel microscope can be used to measure electrical properties of both dielectric and electrically conducting materials.
Electromagnetic field of a charge intersecting a cold plasma boundary in a waveguide
Alekhina, Tatiana Yu.; Tyukhtin, Andrey V. [Radiophysics Department of St. Petersburg University, 1 Ulyanovskaya, St. Petersburg 198504 (Russian Federation)
2011-06-15T23:59:59.000Z
We analyze the electromagnetic field of a charge crossing a boundary between a vacuum and cold plasma in a waveguide. We obtain exact expressions for the field components and the spectral density of the transition radiation. With the steepest descent technique, we investigate the field components. We show that the electromagnetic field has a different structure in a vacuum than in cold plasma. We also develop an algorithm for the computation of the field based on a certain transformation of the integration path. The behavior of the field depending on distance and time and the spectral density depending on frequency are explored for different charge velocities. Some important physical effects are noted. A considerable increase and concentration of the field near the wave front in the plasma is observed for the case of ultrarelativistic particles. In the plasma, the mode envelopes and spectral density show zero points when the charge velocity is within certain limits.
Geometrical vs wave optics under gravitational waves
Raymond Angélil; Prasenjit Saha
2015-05-20T23:59:59.000Z
We present some new derivations of the effect of a plane gravitational wave on a light ray. A simple interpretation of the results is that a gravitational wave causes a phase modulation of electromagnetic waves. We arrive at this picture from two contrasting directions, namely null geodesics and Maxwell's equations, or, geometric and wave optics. Under geometric optics, we express the geodesic equations in Hamiltonian form and solve perturbatively for the effect of gravitational waves. We find that the well-known time-delay formula for light generalizes trivially to massive particles. We also recover, by way of a Hamilton-Jacobi equation, the phase modulation obtained under wave optics. Turning then to wave optics - rather than solving Maxwell's equations directly for the fields, as in most previous approaches - we derive a perturbed wave equation (perturbed by the gravitational wave) for the electromagnetic four-potential. From this wave equation it follows that the four-potential and the electric and magnetic fields all experience the same phase modulation. Applying such a phase modulation to a superposition of plane waves corresponding to a Gaussian wave packet leads to time delays.
Radiation Reaction, Renormalization and Poincaré Symmetry
Yurij Yaremko
2005-11-25T23:59:59.000Z
We consider the self-action problem in classical electrodynamics of a massive point-like charge, as well as of a massless one. A consistent regularization procedure is proposed, which exploits the symmetry properties of the theory. The radiation reaction forces in both 4D and 6D are derived. It is demonstrated that the Poincar\\'e-invariant six-dimensional electrodynamics of the massive charge is renormalizable theory. Unlike the massive case, the rates of radiated energy-momentum tend to infinity whenever the source is accelerated. The external electromagnetic fields, which do not change the velocity of the particle, admit only its presence within the interaction area. The effective equation of motion is the equation for eigenvalues and eigenvectors of the electromagnetic tensor. The interference part of energy-momentum radiated by two massive point charges arbitrarily moving in flat spacetime is evaluated. It is shown that the sum of work done by Lorentz forces of charges acting on one another exhausts the effect of combination of outgoing electromagnetic waves generated by the charges.
Electromagnetic space-time crystals. II. Fractal computational approach
G. N. Borzdov
2014-10-20T23:59:59.000Z
A fractal approach to numerical analysis of electromagnetic space-time crystals, created by three standing plane harmonic waves with mutually orthogonal phase planes and the same frequency, is presented. Finite models of electromagnetic crystals are introduced, which make possible to obtain various approximate solutions of the Dirac equation. A criterion for evaluating accuracy of these approximate solutions is suggested.
Effects of radiation reaction in relativistic laser acceleration
Hadad, Y.; Labun, L.; Rafelski, J.; Elkina, N.; Klier, C.; Ruhl, H. [Departments of Physics and Mathematics, University of Arizona, Tucson, Arizona, 85721 (United States); Department fuer Physik der Ludwig-Maximillians-Universitaet, Theresienstrasse 37A, 80333 Muenchen (Germany)
2010-11-01T23:59:59.000Z
The goal of this paper is twofold: to explore the response of classical charges to electromagnetic force at the level of unity in natural units and to establish a criterion that determines physical parameters for which the related radiation-reaction effects are detectable. In pursuit of this goal, the Landau-Lifshitz equation is solved analytically for an arbitrary (transverse) electromagnetic pulse. A comparative study of the radiation emission of an electron in a linearly polarized pulse for the Landau-Lifshitz equation and for the Lorentz force equation reveals the radiation-reaction-dominated regime, in which radiation-reaction effects overcome the influence of the external fields. The case of a relativistic electron that is slowed down by a counterpropagating electromagnetic wave is studied in detail. We further show that when the electron experiences acceleration of order unity, the dynamics of the Lorentz force equation, the Landau-Lifshitz equation and the Lorentz-Abraham-Dirac equation all result in different radiation emission that could be distinguished in experiment. Finally, our analytic and numerical results are compared with those appearing in the literature.
Light scattering by radiation fields: the optical medium analogy
Donato Bini; Pierluigi Fortini; Andrea Geralico; Maria Haney; Antonello Ortolan
2014-08-23T23:59:59.000Z
The optical medium analogy of a radiation field generated by either an exact gravitational plane wave or an exact electromagnetic wave in the framework of general relativity is developed. The equivalent medium of the associated background field is inhomogeneous and anisotropic in the former case, whereas it is inhomogeneous but isotropic in the latter. The features of light scattering are investigated by assuming the interaction region to be sandwiched between two flat spacetime regions, where light rays propagate along straight lines. Standard tools of ordinary wave optics are used to study the deflection of photon paths due to the interaction with the radiation fields, allowing for a comparison between the optical properties of the equivalent media associated with the different background fields.
Ditmire, Todd
. This is believed to be due to the stabilizing effect of a relatively thick blast wave shell resulting in part from of Ultrafast Laser-Driven Radiative Blast Waves M.J. Edwards,1 A. J. MacKinnon,1 J. Zweiback,1 K. Shigemori,2 D blast waves produced by the deposition of femtosecond laser pulses in gas jets. In high-Z gases
Diffraction of surface wave on conducting rectangular wedge
Igor A. Kotelnikov; Vasily V. Gerasimov; Boris A. Knyazev
2013-01-16T23:59:59.000Z
Diffraction of a surface wave on a rectangular wedge with impedance faces is studied using the Sommerfeld-Malyuzhinets technique. An analog of Landau's bypass rule in the theory of plasma waves is introduced for selection of a correct branch of the Sommerfeld integral, and the exact solution is given in terms of imaginary error function. The formula derived is valid both in the near-field and far-wave zones. It is shown that a diffracted surface wave is completely scattered into freely propagating electromagnetic waves and neither reflected nor transmitted surface waves are generated in case of bare metals which have positive real part of surface impedance. The scattered waves propagate predominantly at a grazing angle along the direction of propagation of the incident surface wave and mainly in the upper hemisphere regarding the wedge face. The profile of radiated intensity is nonmonotonic and does not resemble the surface wave profile which exponentially evanesces with the distance from the wedge face. Comparison with experiments carried out in the terahertz spectral range at Novosibirsk free electron laser has shown a good agreement of the theory and the experiments.
3-D Wave Propagation Simulation in Complex Indoor Structures Farshid Aryanfar' and Kamal Sarabandi
Sarabandi, Kamal
3-D Wave Propagation Simulation in Complex Indoor Structures Farshid Aryanfar' and Kamal Sarabandi in different environments is important for specifying system parameters. Recently, wave propagation prediction electromagnetic wave propagation models have been developed. Examination of reported wave propagation algorithms
Investigation of electromagnetic welding
Pressl, Daniel G. (Daniel Gerd)
2009-01-01T23:59:59.000Z
We propose several methodologies to study and optimize the electromagnetic process for Electromagnetic Forming (EMF) and Welding (EMW), thereby lowering the necessary process energy up to a factor of three and lengthening ...
Terahertz radiation from laser accelerated electron bunches
2004-01-01T23:59:59.000Z
NUMBER 5 MAY 2004 Terahertz radiation from laser acceleratedand millimeter wave radiation from laser acceleratedNo. 5, May 2004 Terahertz radiation from laser accelerated
Ushie, P O; Bolaji, Ayinmode; Osahun, O D
2013-01-01T23:59:59.000Z
We present the result of a preliminary assessment of radio-frequency radiation exposure from selected mobile base stations in Ajaokuta environs. The Power density of RF radiation within a radial distance of 125m was measured. Although values fluctuated due to the influence of other factors, including wave interference from other electromagnetic sources around reference base stations, we show from analysis that radiation exposure level is below the standard limit (4.5W/sqm for 900MHz and 9W/sqm for 18000MHz) set by the International Commission on Non-ionizing Radiation Protection (ICNIRP) and other regulatory agencies.
Electromagnetic Signatures of Massive Black Hole Binaries
Tamara Bogdanovic; Britton D. Smith; Michael Eracleous; Steinn Sigurdsson
2006-09-28T23:59:59.000Z
We model the electromagnetic emission signatures of massive black hole binaries (MBHBs) with an associated gas component. The method comprises numerical simulations of relativistic binaries and gas coupled with calculations of the physical properties of the emitting gas. We calculate the accretion powered UV/X-ray and Halpha light curves and the Halpha emission line profiles. The simulations have been carried out with a modified version of the parallel tree SPH code Gadget. The heating, cooling, and radiative processes for the solar metallicity gas have been calculated with the photoionization code Cloudy. We investigate gravitationally bound, sub-parsec binaries which have not yet entered the gravitational radiation phase. The results from the first set of calculations, carried out for a coplanar binary and gas disk, suggest that the outbursts in the X-ray light curve are pronounced during pericentric passages and can serve as a fingerprint for this type of binaries if periodic outbursts are a long lived signature of the binary. The Halpha emission-line profiles also offer strong indications of a binary presence and may be used as a criterion for selection of MBHB candidates for further monitoring from existing archival data. The orbital period and mass ratio of a binary could be determined from the Halpha light curves and profiles of carefully monitored candidates. Although systems with the orbital periods studied here are not within the frequency band of the Laser Interferometer Space Antenna (LISA), their discovery is important for understanding of the merger rates of MBHBs and the evolution of such binaries through the last parsec and towards the detectable gravitational wave window.
Electromagnetic energy dispersion in a 5D universe
Hartnett, John G. [School of Physics, University of Western Australia, 35 Stirling Hwy, Crawley 6009 WA Australia (Australia)
2010-06-15T23:59:59.000Z
Electromagnetism is analyzed in a 5D expanding universe. Compared to the usual 4D description of electrodynamics it can be viewed as adding effective charge and current densities to the universe that are static in time. These lead to effective polarization and magnetization of the vacuum, which is most significant at high redshift. Electromagnetic waves propagate but group and phase velocities are dispersive. This introduces a new energy scale to the cosmos. And as a result electromagnetic waves propagate with superluminal speeds but no energy is transmitted faster than the canonical speed of light c.
Edmond, J.A.; Palmour, J.W.
1991-04-30T23:59:59.000Z
There were three primary objectives for this reporting period. The first was to electrically characterize junction diodes as a function of temperature. This included both current-voltage (I-V) and capacitance-voltage (C-V) measurements. The second was to fabricate low (about 125 V) and medium (about 450 V) voltage p-n junction rectifiers for neutron and gamma exposure tests. The third objective was to fabricate JFET devices with reduced gate and drain leakage currents than those discussed in the previous report and to package these devices in preparation for radiation testing.
Andreev, A A; Galkin, A L; Kalashnikov, M P; Korobkin, V V; Romanovsky, Mikhail Yu; Shiryaev, O B [A M Prokhorov General Physics Institute, Russian Academy of Sciences, Moscow (Russian Federation)
2011-08-31T23:59:59.000Z
We study the motion of an electron and emission of electromagnetic waves by an electron in the field of a relativistically intense laser pulse. The dynamics of the electron is described by the Newton equation with the Lorentz force in the right-hand side. It is shown that the electrons may be ejected from the interaction region with high energy. The energy spectrum of these electrons and the technique of using the spectrum to assess the maximal intensity in the focus are analysed. It is found that electromagnetic radiation of an electron moving in an intense laser field occurs within a small angle around the direction of the electron trajectory tangent. The tangent quickly changes its direction in space; therefore, electromagnetic radiation of the electron in the far-field zone in a certain direction in the vicinity of the tangent is a short pulse with a duration as short as zeptoseconds. The calculation of the temporary and spectral distribution of the radiation field is carried out. (superintense laser fields)
Symmetry aspects of fermions coupled to torsion and electromagnetic fields
J. L. Boldo; C. A. G. Sasaki
2002-09-24T23:59:59.000Z
We study and explore the symmetry properties of fermions coupled to dynamical torsion and electromagnetic fields. The stability of the theory upon radiative corrections as well as the presence of anomalies are investigated.
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. ???, XXXX, DOI:10.1029/, Interferometric electromagnetic of a direct pulse-echo ex- periment in a three-dimensional configuration. The con- dition-dimensional media. Wave propagation invariants have been used in acoustic, elastic and electromagnetic wave
L. Montagnier; J. Aissa; E. Del Giudice; C. Lavallee; A. Tedeschi; G. Vitiello
2010-12-23T23:59:59.000Z
Some bacterial and viral DNA sequences have been found to induce low frequency electromagnetic waves in high aqueous dilutions. This phenomenon appears to be triggered by the ambient electromagnetic background of very low frequency. We discuss this phenomenon in the framework of quantum field theory. A scheme able to account for the observations is proposed. The reported phenomenon could allow to develop highly sensitive detection systems for chronic bacterial and viral infections.
Electromagnetically driven peristaltic pump
Marshall, Douglas W. (Blackfoot, ID)
2000-01-01T23:59:59.000Z
An electromagnetic peristaltic pump apparatus may comprise a main body section having an inlet end and an outlet end and a flexible membrane which divides the main body section into a first cavity and a second cavity. The first cavity is in fluid communication with the inlet and outlet ends of the main body section. The second cavity is not in fluid communication with the first cavity and contains an electrically conductive fluid. The second cavity includes a plurality of electrodes which are positioned within the second cavity generally adjacent the flexible membrane. A magnetic field generator produces a magnetic field having a plurality of flux lines at least some of which are contained within the second cavity of the main body section and which are oriented generally parallel to a flow direction in which a material flows between the inlet and outlet ends of the main body section. A control system selectively places a voltage potential across selected ones of the plurality of electrodes to deflect the flexible membrane in a wave-like manner to move material contained in the first cavity between the inlet and outlet ends of the main body section.
Betzwieser, Joseph (Joseph Charles)
2008-01-01T23:59:59.000Z
Over the last several years the Laser Interferometer Gravitational Wave Observatory (LIGO) has been making steady progress in improving the sensitivities of its three interferometers, two in Hanford, Washington, and one ...
SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS
Steven D. Novack; Dale K. Kotter; Dennis Slafer; Patrick Pinhero
2008-08-01T23:59:59.000Z
This research explores a new efficient approach for producing electricity from the abundant energy of the sun. A nanoantenna electromagnetic collector (NEC) has been designed, prototyped, and tested. Proof of concept has been validated. The device targets mid-infrared wavelengths where conventional photovoltaic (PV) solar cells do not respond but is abundant in solar energy. The initial concept of designing NEC antennas was based on scaling of radio frequency antenna theory. This approach has proven unsuccessful by many due to not fully understanding and accounting for the optical behavior of materials in the THz region. Also until recent years the nanofabrication methods were not available to fabricate the optical antenna elements. We have addressed and overcome both technology barriers. Several factors were critical in successful implementation of NEC including: 1) frequency-dependent modeling of antenna elements, 2) selection of materials with proper THz properties and 3) novel manufacturing methods that enable economical large-scale manufacturing. The work represents an important step toward the ultimate realization of a low-cost device that will collect as well as convert this radiation into electricity, which will lead to a wide spectrum, high conversion efficiency, and low cost solution to complement conventional PVs.
Poignard, Clair
, the governments have imposed some limitations to the authorized radiated fields by the power systems. It has been a more acceptable limit to these radiated fields. On the other hand, electromagnetic fields are used is obtained by submitting locally the patient to a radiofrequency (RF) electromagnetic field. The focalization
ac rectangular wave: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
vibration analysis. I. Mansour Nikkhah-bahrami; Masih Loghmani; Mostafa Pooyanfar 6 Propagation of Electromagnetic Waves on a Rectangular Lattice of Polarizable Points...
Electromagnetic probes of the QGP
E. L. Bratkovskaya; O. Linnyk; W. Cassing
2014-09-15T23:59:59.000Z
We investigate the properties of the QCD matter across the deconfinement phase transition in the scope of the parton-hadron string dynamics (PHSD) transport approach. We present here in particular the results on the electromagnetic radiation, i.e. photon and dilepton production, in relativistic heavy-ion collisions. By comparing our calculations for the heavy-ion collisions to the available data, we determine the relative importance of the various production sources and address the possible origin of the observed strong elliptic flow $v_2$ of direct photons. We argue that the different centrality dependence of the hadronic and partonic sources for direct photon production in nucleus-nucleus collisions can be employed to shed some more light on the origin of the photon $v_2$ "puzzle". While the dilepton spectra at low invariant mass show in-medium effects like an enhancement from multiple baryonic resonance formation or a collisional broadening of the vector meson spectral functions, the dilepton yield at high invariant masses (above 1.1 GeV) is dominated by QGP contributions for central heavy-ion collisions at ultra-relativistic energies. This allows to have an independent view on the parton dynamics via their electromagnetic massive radiation.
Low-frequency electromagnetic field in a Wigner crystal
Stupka, Anton [Oles Honchar Dnipropetrovs'k National University, Gagarin Ave., 72, 49010 Dnipropetrovs'k (Ukraine)
2013-03-15T23:59:59.000Z
Long-wave low-frequency oscillations are described in a Wigner crystal by generalization of the reverse continuum model for the case of electronic lattice. The internal self-consistent long-wave electromagnetic field is used to describe the collective motions in the system. The eigenvectors and eigenvalues of the obtained system of equations are derived. The velocities of longitudinal and transversal sound waves are found.
Direct and Inverse Problems for Wave Propagation in Random Media February 29, 2000
Asch, Mark
vector and #27;(z) is the dissipation. The local acoustic sound speed is given by c(z) = s K(z) #26;(z Abstract The propagation of waves (acoustic, elastic, electromagnetic) in randomly layered media is highly that our work on the acoustic wave equation can be generalized to elastic waves and electromagnetic waves
Joshua S. Bloom; Daniel E. Holz; Scott A. Hughes; Kristen Menou; Allan Adams; Scott F. Anderson; Andy Becker; Geoffrey C. Bower; Niel Brandt; Bethany Cobb; Kem Cook; Alessandra Corsi; Stefano Covino; Derek Fox; Andrew Fruchter; Chris Fryer; Jonathan Grindlay; Dieter Hartmann; Zoltan Haiman; Bence Kocsis; Lynne Jones; Abraham Loeb; Szabolcs Marka; Brian Metzger; Ehud Nakar; Samaya Nissanke; Daniel A. Perley; Tsvi Piran; Dovi Poznanski; Tom Prince; Jeremy Schnittman; Alicia Soderberg; Michael Strauss; Peter S. Shawhan; David H. Shoemaker; Jonathan Sievers; Christopher Stubbs; Gianpiero Tagliaferri; Pietro Ubertini; Przemyslaw Wozniak
2009-02-10T23:59:59.000Z
It is widely expected that the coming decade will witness the first direct detection of gravitational waves (GWs). The ground-based LIGO and Virgo GW observatories are being upgraded to advanced sensitivity, and are expected to observe a significant binary merger rate. The launch of The Laser Interferometer Space Antenna (LISA) would extend the GW window to low frequencies, opening new vistas on dynamical processes involving massive (M >~ 10^5 M_Sun) black holes. GW events are likely to be accompanied by electromagnetic (EM) counterparts and, since information carried electromagnetically is complementary to that carried gravitationally, a great deal can be learned about an event and its environment if it becomes possible to measure both forms of radiation in concert. Measurements of this kind will mark the dawn of trans-spectral astrophysics, bridging two distinct spectral bands of information. The aim of this whitepaper is to articulate future directions in both theory and observation that are likely to impact broad astrophysical inquiries of general interest. What will EM observations reflect on the nature and diversity of GW sources? Can GW sources be exploited as complementary probes of cosmology? What cross-facility coordination will expand the science returns of gravitational and electromagnetic observations?
Ching-Chuan Su
2006-01-02T23:59:59.000Z
The Compton effect is commonly cited as a demonstration of the particle feature of light, while the wave nature of matter has been proposed by de Broglie and demonstrated by Davisson and Germer with the Bragg diffraction of electron beams. In this investigation, we present an entirely different interpretation of the Compton effect based on the postulates of de Broglie and on an interaction between electromagnetic and matter waves. The speeds of interacting electrons in the Compton scattering are quite fast and its mechanism relies heavily on the mass variation. Thus, based on this wave interpretation, the Compton effect can be viewed as a further demonstration of the postulates of de Broglie for high-speed particles. In addition to the scattered wave, a direct radiation depending on the mass variation is predicted, which provides a means to test the wave interpretation.
Propagation of Partially Coherent Photons in an Ultra-Intense Radiation Gas
Mattias Marklund
2005-03-03T23:59:59.000Z
The scattering of photons off photons at the one-loop level is investigated. We give a short review of the weak field limit, as given by the first order term in the series expansion of the Heisenberg-Euler Lagrangian. The dispersion relation for a photon in a radiation gas is presented. Based on this, a wave kinetic equation and a set of fluid equations is formulated. These equations describe the interaction between a partially coherent electromagnetic pulse and an intense radiation gas. The implications of the results are discussed.
Global aspects of radiation memory
J. Winicour
2014-10-11T23:59:59.000Z
Gravitational radiation has a memory effect represented by a net change in the relative positions of test particles. Both the linear and nonlinear sources proposed for this radiation memory are of the "electric" type, or E mode, as characterized by the even parity of the polarization pattern. Although "magnetic" type, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory in which the velocity of charged particles obtain a net "kick". Again, the physically realistic sources of electromagnetic radiation memory that have been identified are of the electric type. In this paper, a global null cone description of the electromagnetic field is applied to establish the non-existence of B mode radiation memory and the non-existence of E mode radiation memory due to a bound charge distribution.
Chung, Deborah D.L.
by radiofrequency radiation (such as that emitted by a cellular phone), there is a growing need for devel- oping) shielding refers to the blocking of electromagnetic radiation so that the radiation essentially cannot pass conductors such as met- als and carbons mainly shield by reflection of the radiation. On the other hand
Electromagnetic Radiation and in-Medium Effects
Ralf Rapp
2005-03-14T23:59:59.000Z
The theory of thermal photon and dilepton emission from a hot and dense hadronic gas, as well as from the Quark-Gluon Plasma, is reviewed in the context of extracting in-medium properties of the matter constituents. In phenomenological applications to ultrarelativistic heavy-ion collisions we focus on recent photon and dilepton spectra as measured by WA98 and CERES/NA45, respectively, at CERN-SPS energies.
Photophoresis and the scattering of electromagnetic radiation
Ipser, J.R.
1985-09-01T23:59:59.000Z
Electron-microscope photographs of soot lend support to the picture in which a soot particle is modeled as a collection of chains of small carbon spheres. The soot particle itself is typically considerably larger than the small carbon spheres making up the chains. Thus the soot particles might have a size approx.0.1 - 1 ..mu..m while the small carbon spheres might have a size approx.0.03 ..mu..m in typical situations. Further, measurements of the density of soot yield values much less than that of normal carbon, indicating that an individual soot particle has a rather small filling factor, i.e., the fraction of the volume of the particle tht is occupied by chains. If a soot particle is taken to be a sphere partially filled with carbon chains, what are its scattering and absorption properties. Several workers have adopted the view that the net scattering and absorption properties can be determined simply by summing the cross-sections for the individual small carbon spheres. We feel that such a procedure cannot be valid in general because it neglects coherence effects among the various randomly located scatterers within the soot particle. It appears that in a first rough approximation the scattering and absorption properties of soot can be determined by estimating the effective dielectric constant of a soot sphere.
Motai, Yuichi
. This electronic system can be used to monitor VLF electromagnetic radiation in residential and occupational-Low-Frequency Electromagnetic Field Detector With Data Acquisition Saba A. Hanna, Member, IEEE, Yuichi Motai, Member, IEEE-made VLF electromagnetic fields are stronger and have been suspected of causing negative health effects
Electromagnetic rotational actuation.
Hogan, Alexander Lee
2010-08-01T23:59:59.000Z
There are many applications that need a meso-scale rotational actuator. These applications have been left by the wayside because of the lack of actuation at this scale. Sandia National Laboratories has many unique fabrication technologies that could be used to create an electromagnetic actuator at this scale. There are also many designs to be explored. In this internship exploration of the designs and fabrications technologies to find an inexpensive design that can be used for prototyping the electromagnetic rotational actuator.
The CLAS Forward Electromagnetic Calorimeter
M. Amarian; Geram Asryan; Kevin Beard; Will Brooks; Volker Burkert; Tom Carstens; Alan Coleman; Raphael Demirchyan; Yuri Efremenko; Hovanes Egiyan; Kim Egiyan; Herb Funsten; Vladimir Gavrilov; Kevin L. Giovanetti; R.M. Marshall; Berhard Mecking; R.C. Minehart; H. Mkrtchan; Mavrik Ohandjanyan; Youri Sharabian; L.C. Smith; Stepan Stepanyan; W.A. Stephens; T.Y. Tung; Carl Zorn
2001-05-01T23:59:59.000Z
The CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab utilizes six iron-free superconducting coils to provide an approximately toroidal magnetic field. The six sectors are instrumented individually to form six independent spectrometers. The forward region (8deg < (theta) < 45deg) of each sector is equipped with a lead-scintillator electromagnetic sampling calorimeter (EC), 16 radiation lengths thick, using a novel triangular geometry with stereo readout. With its good energy and position resolution, the EC is used to provide the primary electron trigger for CLAS. It is also used to reject pions, reconstruct pi-0 and eta decays and detect neutrons, This paper treats the design, construction and performance of the calorimeter.
Solar Radiation and Asteroidal Motion
Jozef Klacka
2000-09-07T23:59:59.000Z
Effects of solar wind and solar electromagnetic radiation on motion of asteroids are discussed. The results complete the statements presented in Vokrouhlick\\'{y} and Milani (2000). As for the effect of electromagnetic radiation, the complete equation of motion is presented to the first order in $v/c$ -- the shape of asteroid (spherical body is explicitly presented) and surface distribution of albedo should be taken into account. Optical quantities must be calculated in proper frame of reference.
Radiation damping and decoherence in quantum electrodynamics
Heinz-Peter Breuer; Francesco Petruccione
2002-10-02T23:59:59.000Z
The processes of radiation damping and decoherence in Quantum Electrodynamics are studied from an open system's point of view. Employing functional techniques of field theory, the degrees of freedom of the radiation field are eliminated to obtain the influence phase functional which describes the reduced dynamics of the matter variables. The general theory is applied to the dynamics of a single electron in the radiation field. From a study of the wave packet dynamics a quantitative measure for the degree of decoherence, the decoherence function, is deduced. The latter is shown to describe the emergence of decoherence through the emission of bremsstrahlung caused by the relative motion of interfering wave packets. It is argued that this mechanism is the most fundamental process in Quantum Electrodynamics leading to the destruction of coherence, since it dominates for short times and because it is at work even in the electromagnetic field vacuum at zero temperature. It turns out that decoherence trough bremsstrahlung is very small for single electrons but extremely large for superpositions of many-particle states.
Mathematical model of the seismic electromagnetic signals (SEMS) in non crystalline substances
Dennis, L. C. C.; Yahya, N.; Daud, H.; Shafie, A. [Electromagnetic cluster, Universiti Teknologi Petronas, 31750 Tronoh, Perak (Malaysia)
2012-09-26T23:59:59.000Z
The mathematical model of seismic electromagnetic waves in non crystalline substances is developed and the solutions are discussed to show the possibility of improving the electromagnetic waves especially the electric field. The shear stress of the medium in fourth order tensor gives the equation of motion. Analytic methods are selected for the solutions written in Hansen vector form. From the simulated SEMS, the frequency of seismic waves has significant effects to the SEMS propagating characteristics. EM waves transform into SEMS or energized seismic waves. Traveling distance increases once the frequency of the seismic waves increases from 100% to 1000%. SEMS with greater seismic frequency will give seismic alike waves but greater energy is embedded by EM waves and hence further distance the waves travel.
Gravitational Waves and Their Memory in General Relativity
Bieri, Lydia; Yau, Shing-Tung
2015-01-01T23:59:59.000Z
General relativity explains gravitational radiation from binary black hole or neutron star mergers, from core-collapse supernovae and even from the inflation period in cosmology. These waves exhibit a unique effect called memory or Christodoulou effect, which in a detector like LIGO or LISA shows as a permanent displacement of test masses and in radio telescopes like NANOGrav as a change in the frequency of pulsars' pulses. It was shown that electromagnetic fields and neutrino radiation enlarge the memory. Recently it has been understood that the two types of memory addressed in the literature as `linear' and `nonlinear' are in fact two different phenomena. The former is due to fields that do not and the latter is due to fields that do reach null infinity.
Gravitational Waves and Their Memory in General Relativity
Lydia Bieri; David Garfinkle; Shing-Tung Yau
2015-05-20T23:59:59.000Z
General relativity explains gravitational radiation from binary black hole or neutron star mergers, from core-collapse supernovae and even from the inflation period in cosmology. These waves exhibit a unique effect called memory or Christodoulou effect, which in a detector like LIGO or LISA shows as a permanent displacement of test masses and in radio telescopes like NANOGrav as a change in the frequency of pulsars' pulses. It was shown that electromagnetic fields and neutrino radiation enlarge the memory. Recently it has been understood that the two types of memory addressed in the literature as `linear' and `nonlinear' are in fact two different phenomena. The former is due to fields that do not and the latter is due to fields that do reach null infinity.
Reduced Order Computational Methods for Electromagnetic Material Interrogation Using Pulsed Signals consider the interrogation by means of a pulsed planar electromagnetic wave of a dielectric slab properties by means of a non-invasive probes such as low energy electromag- netic pulses is desirable
Equations of a Moving Mirror and the Electromagnetic Field
Luis Octavio Castaños; Ricardo Weder
2014-10-28T23:59:59.000Z
We consider a slab of a material that is linear, isotropic, non-magnetizable, ohmic, and electrically neutral when it is at rest. The slab interacts with the electromagnetic field through radiation pressure. Using a relativistic treatment, we deduce the exact equations governing the dynamics of the field and of the slab, as well as, approximate equations to first order in the velocity and the acceleration of the slab. As a consequence of the motion of the slab, the field must satisfy a wave equation with damping and slowly varying coefficients plus terms that are small when the time-scale of the evolution of the mirror is much smaller than that of the field. Moreover, the dynamics of the mirror involve a time-dependent mass arising from the interaction with the field and it is related to the effective mass of mechanical oscillators used in optomechanics. By the same reason, the mirror is subject to a velocity dependent force which is related to the much sought cooling of mechanical oscillators in optomechanics.
Electromagnetic Scattering by Spheres of Topological Insulators
Ge, Lixin; Zi, Jian
2015-01-01T23:59:59.000Z
The electromagnetic scattering properties of topological insulator (TI) spheres are systematically studied in this paper. Unconventional backward scattering caused by the topological magneto-electric (TME) effect of TIs are found in both Rayleigh and Mie scattering regimes. This enhanced backward scattering can be achieved by introducing an impedance-matched background which can suppress the bulk scattering. For the cross-polarized scattering coefficients, interesting antiresonances are found in the Mie scattering regime, wherein the cross-polarized electromagnetic fields induced by the TME effect are trapped inside TI spheres. In the Rayleigh limit, the quantized TME effect of TIs can be determined by measuring the electric-field components of scattered waves in the far field.
Electromagnetic properties of baryons
Ledwig, T.; Pascalutsa, V.; Vanderhaeghen, M. [Institut fuer Kernphysik, Universitaet Mainz, D-55099 Mainz (Germany); Martin-Camalich, J. [Departamento de Fisica Teorica and IFIC, Universidad de Valencia-CSIC, Spain and Department of Physics and Astronomy, University of Sussex, BN1 9Qh, Brighton (United Kingdom)
2011-10-21T23:59:59.000Z
We discuss the chiral behavior of the nucleon and {Delta}(1232) electromagnetic properties within the framework of a SU(2) covariant baryon chiral perturbation theory. Our one-loop calculation is complete to the order p{sup 3} and p{sup 4}/{Delta} with {Delta} as the {Delta}(1232)-nucleon energy gap. We show that the magnetic moment of a resonance can be defined by the linear energy shift only when an additional relation between the involved masses and the applied magnetic field strength is fulfilled. Singularities and cusps in the pion mass dependence of the {Delta}(1232) electromagnetic moments reflect a non-fulfillment. We show results for the pion mass dependence of the nucleon iso-vector electromagnetic quantities and present preliminary results for finite volume effects on the iso-vector anomalous magnetic moment.
Borisov, A. V.; Kerimov, B. K.; Sizin, P. E., E-mail: borisov@phys.msu.ru [Moscow State University (Russian Federation)
2012-11-15T23:59:59.000Z
Expressions for the power of neutrino radiation from a degenerate electron gas in a strong magnetic field are derived for the case of neutrino-pair photoproduction via the weak and electromagnetic interaction mechanisms (it is assumed that the neutrino possesses electromagnetic form factors). It is shown that the neutrino luminosity of a medium in the electromagnetic reaction channel may exceed substantially the luminosity in the weak channel. Relative upper bounds on the effective neutrino magnetic moment are obtained.
Radiation Processing -an overview
of radiation Â· Facilities Â Gamma Â electrons Â X-ray Â Safety Â· Sterilisation of medical devices Â· Food irradiation Â· Material modification #12;3 Content Â Part 2 Â· Environmental applications Â· Other applications Radiation Â· Energy in the form of waves or moving subatomic particles Irradiation Â· Exposure to radiation
Millimeter Wave Sensor For On-Line Inspection Of Thin Sheet Dielectrics
Bakhtiari, Sasan (Westmont, IL); Gopalsami, Nachappa (Naperville, IL); Raptis, Apostolos C. (Downers Grove, IL)
1999-03-23T23:59:59.000Z
A millimeter wave sensor is provided for non-destructive inspection of thin sheet dielectric materials. The millimeter wave sensor includes a Gunn diode oscillator (GDO) source generating a mill meter wave electromagnetic energy signal having a single frequency. A heater is coupled to the GDO source for stabilizing the single frequency. A small size antenna is coupled to the GDO source for transmitting the millimeter wave electromagnetic energy signal to a sample material and for receiving a reflected millimeter wave electromagnetic energy signal from the sample material. Ferrite circulator isolators coupled between the GDO source and the antenna separate the millimeter wave electromagnetic energy signal into transmitted and received electromagnetic energy signal components and a detector detects change in both amplitude and phase of the transmitted and received electromagnetic energy signal components. A millimeter wave sensor is provided for non-destructive inspection of thin sheet dielectric materials. The millimeter wave sensor includes a Gunn diode oscillator (GDO) source generating a mill meter wave electromagnetic energy signal having a single frequency. A heater is coupled to the GDO source for stabilizing the single frequency. A small size antenna is coupled to the GDO source for transmitting the millimeter wave electromagnetic energy signal to a sample material and for receiving a reflected millimeter wave electromagnetic energy signal from the sample material. Ferrite circulator isolators coupled between the GDO source and the antenna separate the millimeter wave electromagnetic energy signal into transmitted and received electromagnetic energy signal components and a detector detects change in both amplitude and phase of the transmitted and received electromagnetic energy signal components.
Radiation reaction in quantum field theory
Atsushi Higuchi
2004-03-30T23:59:59.000Z
We investigate radiation-reaction effects for a charged scalar particle accelerated by an external potential realized as a space-dependent mass term in quantum electrodynamics. In particular, we calculate the position shift of the final-state wave packet of the charged particle due to radiation at lowest order in the fine structure constant alpha and in the small h-bar approximation. We show that it disagrees with the result obtained using the Lorentz-Dirac formula for the radiation-reaction force, and that it agrees with the classical theory if one assumes that the particle loses its energy to radiation at each moment of time according to the Larmor formula in the static frame of the potential. However, the discrepancy is much smaller than the Compton wavelength of the particle. We also point out that the electromagnetic correction to the potential has no classical limit. (Correction. Surface terms were erroneously discarded to arrive at Eq. (59). By correcting this error we find that the position shift according to the Lorentz-Dirac theory obtained from Eq. (12) is reproduced by quantum field theory in the hbar -> 0 limit. We also find that the small V(z) approximation is unnecessary for this agreement. See Sec. VII.)
FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTED FRAME TRANSFORMATION
Fawley, William
2010-01-01T23:59:59.000Z
FULL ELECTROMAGNETIC FEL SIMULATION VIA THE LORENTZ-BOOSTEDrest frame), the red-shifted FEL radiation and blue-shiftedper- mit direct study of FEL problems for which the eikonal
Tsvankin, Ilya
of hydrocarbons. Conventional AVO algo- rithms are based on analytic expressions for the plane P-wave reflection
Propagation of Light in the Field of Stationary and Radiative Gravitational Multipoles
Sergei Kopeikin; Pavel Korobkov; Alexander Polnarev
2006-03-15T23:59:59.000Z
Extremely high precision of near-future radio/optical interferometric observatories like SKA, Gaia, SIM and the unparalleled sensitivity of LIGO/LISA gravitational-wave detectors demands more deep theoretical treatment of relativistic effects in the propagation of electromagnetic signals through variable gravitational fields of the solar system, oscillating and precessing neutron stars, coalescing binary systems, exploding supernova, and colliding galaxies. Especially important for future gravitational-wave observatories is the problem of propagation of light rays in the field of multipolar gravitational waves emitted by a localized source of gravitational radiation. Present paper suggests physically-adequate and consistent mathematical solution of this problem in the first post-Minkowskian approximation of General Relativity which accounts for all time-dependent multipole moments of an isolated astronomical system.
The scientific potential of space-based gravitational wave detectors
Jonathan R. Gair
2014-08-28T23:59:59.000Z
The millihertz gravitational wave band can only be accessed with a space-based interferometer, but it is one of the richest in potential sources. Observations in this band have amazing scientific potential. The mergers between massive black holes with mass in the range 10 thousand to 10 million solar masses, which are expected to occur following the mergers of their host galaxies, produce strong millihertz gravitational radiation. Observations of these systems will trace the hierarchical assembly of structure in the Universe in a mass range that is very difficult to probe electromagnetically. Stellar mass compact objects falling into such black holes in the centres of galaxies generate detectable gravitational radiation for several years prior to the final plunge and merger with the central black hole. Measurements of these systems offer an unprecedented opportunity to probe the predictions of general relativity in the strong-field and dynamical regime. Millihertz gravitational waves are also generated by millions of ultra-compact binaries in the Milky Way, providing a new way to probe galactic stellar populations. ESA has recognised this great scientific potential by selecting The Gravitational Universe as its theme for the L3 large satellite mission, scheduled for launch in ~2034. In this article we will review the likely sources for millihertz gravitational wave detectors and describe the wide applications that observations of these sources could have for astrophysics, cosmology and fundamental physics.
Radiation trapping in coherent media
A. B. Matsko; I. Novikova; M. O. Scully; G. R. Welch
2001-01-31T23:59:59.000Z
We show that the effective decay rate of Zeeman coherence, generated in a Rb87 vapor by linearly polarized laser light, increases significantly with the atomic density. We explain this phenomenon as the result of radiation trapping. Our study shows that radiation trapping must be taken into account to fully understand many electromagnetically induced transparency experiments with optically thick media.
Electromagnetic solitary pulses in a magnetized electron-positron plasma
Shukla, P. K. [RUB International Chair, International Centre for Advanced Studies in Physical Sciences, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Eliasson, B. [Institut fuer Theoretische Physik, Fakultaet fuer Physik und Astronomie, Ruhr-Universitaet Bochum, D-44780 Bochum (Germany); Stenflo, L. [Department of Physics, Linkoeping University, SE-58183 Linkoeping (Sweden)
2011-03-15T23:59:59.000Z
A theory for large amplitude compressional electromagnetic solitary pulses in a magnetized electron-positron (e-p) plasma is presented. The pulses, which propagate perpendicular to the external magnetic field, are associated with the compression of the plasma density and the wave magnetic field. Here the solitary wave magnetic field pressure provides the restoring force, while the inertia comes from the equal mass electrons and positrons. The solitary pulses are formed due to a balance between the compressional wave dispersion arising from the curl of the inertial forces in Faraday's law and the nonlinearities associated with the divergence of the electron and positron fluxes, the nonlinear Lorentz forces, the advection of the e-p fluids, and the nonlinear plasma current densities. The compressional solitary pulses can exist in a well-defined speed range above the Alfven speed. They can be associated with localized electromagnetic field excitations in magnetized laboratory and space plasmas composed of electrons and positrons.
Electromagnetic source localization with finite set of frequency measurements
Abdul Wahab; Amer Rasheed; Rab Nawaz; Saman Anjum
2014-09-16T23:59:59.000Z
A phase conjugation algorithm for localizing an extended radiating electromagnetic source from boundary measurements of the electric field is presented. Measurements are taken over a finite number of frequencies. The artifacts related to the finite frequency data are tackled with $l_1-$regularization blended with the fast iterative shrinkage-thresholding algorithm with backtracking of Beck & Teboulle.
Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations
Kuhn, Markus
Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations Markus G. Kuhn and Ross J, a trusted screen driver can display sensitive information using fonts which minimise the energy the data being processed. Known as compromising emanations or Tempest radiation, a code word for a U.S. gov
Active absorption of electromagnetic pulses in a cavity
Horsley, S A R; Tyc, T; Philbin, T G
2014-01-01T23:59:59.000Z
We show that a pulse of electromagnetic radiation launched into a cavity can be completely absorbed into an infinitesimal region of space, provided one has a high degree of control over the current flowing through this region. We work out explicit examples of this effect in a cubic cavity and a cylindrical one, and experimentally demonstrate the effect in the microwave regime.
Quasi light fields: Extending the light field to coherent radiation
Accardi, Anthony J.
Imaging technologies such as dynamic viewpoint generation are engineered for incoherent radiation using the traditional light field, and for coherent radiation using electromagnetic field theory. We present a model of ...
The Blackbody Radiation Laws in the $ \\textrm{AdS}_5 \\times {\\cal S}^5 $ Spacetime
Ramaton Ramos; Henrique Boschi Filho
2014-09-25T23:59:59.000Z
In the footsteps of our previous work \\cite{RamatonBoschi} we generalize the Stefan-Boltzmann and Wien's displacement laws for the $ \\textrm{AdS}_5 \\times {\\cal S}^5 $ spacetime, the background of the AdS/CFT correspondence foremost realization. Our results take into account the $ \\textrm{AdS}_5 \\times {\\cal S}^5 $ full dimensionality in the electromagnetic field $A^{\\mu}$ wave equation, which yields the higher-dimensional blackbody characteristic features suggested in literature. In particular, the total radiated power and the spectral radiancy match the original Stefan-Boltzmann and Wien's displacement laws in the low-energy regime up to available experimental data.
Bernard F Schutz
2000-03-16T23:59:59.000Z
Gravity is one of the fundamental forces of Nature, and it is the dominant force in most astronomical systems. In common with all other phenomena, gravity must obey the principles of special relativity. In particular, gravitational forces must not be transmitted or communicated faster than light. This means that when the gravitational field of an object changes, the changes ripple outwards through space and take a finite time to reach other objects. These ripples are called gravitational radiation or gravitational waves. This article gives a brief introduction to the physics of gravitational radiation, including technical material suitable for non-specialist scientists.
DEF: The Physical Basis of Electromagnetic Propulsion
Pinheiro, Mario J
2015-01-01T23:59:59.000Z
The very existence of the physical vacuum provides a framework to propose a general mechanism for propelling bodies through an agency of electromagnetic fields, that seat in that medium. When two sub-systems of a general closed device interact via nonlocal and retarded electromagnetic pulses, it is easily shown that they give a nonzero force, and that only tend to comply with the action-to-reaction force in the limit of instantaneous interactions. The arrangement of sub-systems provide a handy way to optimize the unbalanced EM force with the concept of impedance matching. The general properties of the differential electromagnetic force (DEF) are the following: i) it is proportional to the square of the intensity and to the angular wave frequency $\\omega$; ii) to the space between the sub-systems (although in a non-linear manner); iii) it is inversely proportional to the speed of interaction; iv) when the two sub-systems are out-of-phase, DEF is null. The approach is of interest to practical engineering princi...
Millimeter wave transmissometer computer system
Wiberg, J.D.; Widener, K.B.
1990-04-01T23:59:59.000Z
A millimeter wave transmissometer has been designed and built by the Pacific Northwest Laboratory in Richland, Washington for the US Army at the Dugway Proving Grounds in Dugway, Utah. This real-time data acquisition and control system is used to test and characterize battlefield obscurants according to the transmittance of electromagnetic radiation in the millimeter wavelengths. It is an advanced five-frequency instrumentation radar system consisting of a transceiver van and a receiver van deployed at opposite sides of a test grid. The transceiver computer systems is the successful integration of a Digital Equipment Corporation (DEC) VAX 8350, multiple VME bus systems with Motorola M68020 processors (one for each radar frequency), an IEEE-488 instrumentation bus, and an Aptec IOC-24 I/O computer. The software development platforms are the VAX 8350 and an IBM PC/AT. A variety of compilers, cross-assemblers, microcode assemblers, and linkers were employed to facilitate development of the system software. Transmittance measurements from each radar are taken forty times per second under control of a VME based M68020.
Banded electromagnetic stator core
Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.
1994-04-05T23:59:59.000Z
A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figures.
Banded electromagnetic stator core
Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.
1996-06-11T23:59:59.000Z
A stator core for an electromagnetic pump includes a plurality of circumferentially adjoining groups of flat laminations disposed about a common centerline axis and collectively defining a central bore and a discontinuous outer perimeter, with adjacent groups diverging radially outwardly to form V-shaped gaps. An annular band surrounds the groups and is predeterminedly tensioned to clamp together the laminations, and has a predetermined flexibility in a radial direction to form substantially straight bridge sections between the adjacent groups. 5 figs.
J X Zheng-Johansson; P-I Johansson
2006-08-27T23:59:59.000Z
The electromagnetic component waves, comprising together with their generating oscillatory massless charge a material particle, will be Doppler shifted when the charge hence particle is in motion, with a velocity $v$, as a mere mechanical consequence of the source motion. We illustrate here that two such component waves generated in opposite directions and propagating at speed $c$ between walls in a one-dimensional box, superpose into a traveling beat wave of wavelength ${\\mit\\Lambda}_d$$=(\\frac{v}{c}){\\mit\\Lambda}$ and phase velocity $c^2/v+v$ which resembles directly L. de Broglie's hypothetic phase wave. This phase wave in terms of transporting the particle mass at the speed $v$ and angular frequency ${\\mit\\Omega}_d=2\\pi v /{\\mit\\Lambda}_d$, with ${\\mit\\Lambda}_d$ and ${\\mit\\Omega}_d$ obeying the de Broglie relations, represents a de Broglie wave. The standing-wave function of the de Broglie (phase) wave and its variables for particle dynamics in small geometries are equivalent to the eigen-state solutions to Schr\\"odinger equation of an identical system.
Paris-Sud XI, Université de
for the SEAREV wave energy converter (WEC) followed by the design methodology applied to electromagnetic with the SEAREV WEC before discussing the two conversion technologies intended to transform wave energy, including one featuring power leveling. Index Terms wave energy conversion - electromagnetic generator
Coherent hybrid electromagnetic field imaging
Cooke, Bradly J. (Jemez Springs, NM); Guenther, David C. (Los Alamos, NM)
2008-08-26T23:59:59.000Z
An apparatus and corresponding method for coherent hybrid electromagnetic field imaging of a target, where an energy source is used to generate a propagating electromagnetic beam, an electromagnetic beam splitting means to split the beam into two or more coherently matched beams of about equal amplitude, and where the spatial and temporal self-coherence between each two or more coherently matched beams is preserved. Two or more differential modulation means are employed to modulate each two or more coherently matched beams with a time-varying polarization, frequency, phase, and amplitude signal. An electromagnetic beam combining means is used to coherently combine said two or more coherently matched beams into a coherent electromagnetic beam. One or more electromagnetic beam controlling means are used for collimating, guiding, or focusing the coherent electromagnetic beam. One or more apertures are used for transmitting and receiving the coherent electromagnetic beam to and from the target. A receiver is used that is capable of square-law detection of the coherent electromagnetic beam. A waveform generator is used that is capable of generation and control of time-varying polarization, frequency, phase, or amplitude modulation waveforms and sequences. A means of synchronizing time varying waveform is used between the energy source and the receiver. Finally, a means of displaying the images created by the interaction of the coherent electromagnetic beam with target is employed.
Stable operating regime for traveling wave devices
Carlsten, Bruce E. (Los Alamos, NM)
2000-01-01T23:59:59.000Z
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.
Weijgaert, Rien van de
;14/03/2014 6 H L H L L Phase & Group Velocity #12;14/03/2014 7 Doppler Effect #12;14/03/2014 8 Shock Waves #12;14/03/2014 14 Supernova Remnant Cassiopeia A Supernova blast waves #12;14/03/2014 15 Tycho's Remnant (SN 1572AD A SNR flythrough Theory of Supernova Blast Waves Supernovae: Type Ia Subsonic deflagration wave turning
HULBERT,S.L.; WILLIAMS,G.P.
1998-07-01T23:59:59.000Z
Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.
Shock wave in Euler - Heisenberg - Köckel nonlinear vacuum
Lubomir M. Kovachev; Daniela A. Georgieva; Kamen L. Kovachev
2014-09-05T23:59:59.000Z
An analytical approach to the theory of electromagnetic waves in nonlinear vacuum is developed. The evolution of the pulse is governed by a system of nonlinear wave vector equations. Exact solution with own angular momentum in form of a shock wave is obtained.
M. Marklund; P. K. Shukla; B. Eliasson
2005-03-08T23:59:59.000Z
We present a new dispersion relation for photons that are nonlinearly interacting with a radiation gas of arbitrary intensity due to photon-photon scattering. It is found that the photon phase velocity decreases with increasing radiation intensity, it and attains a minimum value in the limit of super-intense fields. By using Hamilton's ray equations, a self-consistent kinetic theory for interacting photons is formulated. The interaction between an electromagnetic pulse and the radiation gas is shown to produce pulse self-compression and nonlinear saturation. Implications of our new results are discussed.
Evaluation of methodologies for estimating vulnerability to electromagnetic pulse effects
Not Available
1984-01-01T23:59:59.000Z
High-altitude electromagnetic pulse (EMP) is an electromagnetic radiation of very short rise time, large amplitude, and brief duration that follows a nuclear explosion above the atmosphere. The area over which a single EMP event is experienced can be very great if the explosion if high enough and large enough. Several such nuclear explosions might render unprotected electronic equipment and systems inoperative over an area as large as the continental United States. Damage may occur when high currents and voltages, driven by EMP, reach vital internal circuits. It is therefore essential to protect the systems and to form some idea of how well they will withstand EMP.
abscopal radiation effects: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
of symmetry. Numerical calculations in three dimensions of the radiative energy density, flux and pressure created by a stationary shock wave show how the radiation decreases...
RADIATION RESEARCH 169, 2837 (2008) 0033-7587/08 $15.00
Jerby, Eli
2008-01-01T23:59:59.000Z
Peripheral Blood Lymphocytes to Radiofrequency Electromagnetic Fields for 72 Hours. Radiat. Res. 169, 2828 RADIATION RESEARCH 169, 2837 (2008) 0033-7587/08 $15.00 2008 by Radiation Research Society. All In Vitro Exposure of Human Peripheral Blood Lymphocytes to Radiofrequency Electromagnetic Fields for 72
Electromagnetic pump stator coil
Fanning, A.W.; Dahl, L.R.
1996-06-25T23:59:59.000Z
An electrical stator coil for an electromagnetic pump includes a continuous conductor strip having first and second terminals at opposite ends thereof and an intermediate section disposed therebetween. The strip is configured in first and second coil halves, with the first coil half including a plurality of windings extending from the first terminal to the intermediate section, and the second coil half including a plurality of windings extending from the second terminal to the intermediate section. The first and second coil halves are disposed coaxially, and the first and second terminals are disposed radially inwardly therefrom with the intermediate section being disposed radially outwardly therefrom. 9 figs.
Electromagnetic pump stator coil
Fanning, Alan W. (San Jose, CA); Dahl, Leslie R. (Livermore, CA)
1996-01-01T23:59:59.000Z
An electrical stator coil for an electromagnetic pump includes a continuous conductor strip having first and second terminals at opposite ends thereof and an intermediate section disposed therebetween. The strip is configured in first and second coil halves, with the first coil half including a plurality of windings extending from the first terminal to the intermediate section, and the second coil half including a plurality of windings extending from the second terminal to the intermediate section. The first and second coil halves are disposed coaxially, and the first and second terminals are disposed radially inwardly therefrom with the intermediate section being disposed radially outwardly therefrom.
Resonant circuit which provides dual-frequency excitation for rapid cycling of an electromagnet
Praeg, W.F.
1982-03-09T23:59:59.000Z
Disclosed is a novel ring-magnet control circuit that permits synchrotron repetition rates much higher than the frequency of the sinusoidal guide field of the ring magnet during particle acceleration. The control circuit generates sinusoidal excitation currents of different frequencies in the half waves. During radio-frequency acceleration of the synchrotron, the control circuit operates with a lower frequency sine wave and, thereafter, the electromagnets are reset with a higher-frequency half sine wave.
Ponderomotive Forces On Waves In Modulated Media
Dodin, I.Y; Fisch, Nathaniel
2014-02-28T23:59:59.000Z
Nonlinear interactions of waves via instantaneous cross-phase modulation can be cast in the same way as ponderomotive wave-particle interactions in high-frequency electromagnetic fi eld. The ponderomotive effect arises when rays of a probe wave scatter off perturbations of the underlying medium produced by a second, modulation wave, much like charged particles scatter off a quasiperiodic field. Parallels with the point-particle dynamics, which itself is generalized by this theory, lead to new methods of wave manipulation, including asymmetric barriers for light.
Experiment Indicates Sound Waves Can Trigger Quakes
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
in a laboratory setting, a Los Alamos researcher and his colleagues have shown that seismic waves-the sounds radiated from earthquakes-can induce earthquake aftershocks, often...
Lucas, Timothy S. (4614 River Mill Ct., Glen Allen, VA 23060)
1991-01-01T23:59:59.000Z
A compressor for compression-evaporation cooling systems, which requires no moving parts. A gaseous refrigerant inside a chamber is acoustically compressed and conveyed by means of a standing acoustic wave which is set up in the gaseous refrigerant. This standing acoustic wave can be driven either by a transducer, or by direct exposure of the gas to microwave and infrared sources, including solar energy. Input and output ports arranged along the chamber provide for the intake and discharge of the gaseous refrigerant. These ports can be provided with optional valve arrangements, so as to increase the compressor's pressure differential. The performance of the compressor in either of its transducer or electromagnetically driven configurations, can be optimized by a controlling circuit. This controlling circuit holds the wavelength of the standing acoustical wave constant, by changing the driving frequency in response to varying operating conditions.
Electromagnetic acoustic transducer
Alers, George A. (Albuquerque, NM); Burns, Jr., Leigh R. (Albuquerque, NM); MacLauchlan, Daniel T. (Sandia Park, NM)
1988-01-01T23:59:59.000Z
A noncontact ultrasonic transducer for studying the acoustic properties of a metal workpiece includes a generally planar magnetizing coil positioned above the surface of the workpiece, and a generally planar eddy current coil between the magnetizing coil and the workpiece. When a large current is passed through the magnetizing coil, a large magnetic field is applied to the near-surface regions of the workpiece. The eddy current coil can then be operated as a transmitter by passing an alternating current therethrough to excite ultrasonic waves in the surface of the workpiece, or operated as a passive receiver to sense ultrasonic waves in the surface by measuring the output signal. The geometries of the two coils can be varied widely to be effective for different types of ultrasonic waves. The coils are preferably packaged in a housing which does not interfere with their operation, but protects them from a variety of adverse environmental conditions.
Franks, Larry A. (Santa Barbara, CA); Lutz, Stephen S. (Santa Barbara, CA); Lyons, Peter B. (Los Alamos, NM)
1981-01-01T23:59:59.000Z
A radiation detection system including a radiation-to-light converter and fiber optic wave guides to transmit the light to a remote location for processing. The system utilizes fluors particularly developed for use with optical fibers emitting at wavelengths greater than about 500 nm and having decay times less than about 10 ns.
Jha, Pallavi; Kumar Verma, Nirmal [Department of Physics, University of Lucknow, Lucknow-226007 (India)
2014-06-15T23:59:59.000Z
A one-dimensional numerical model for studying terahertz radiation generation by intense laser pulses propagating, in the extraordinary mode, through magnetized plasma has been presented. The direction of the static external magnetic field is perpendicular to the polarization as well as propagation direction of the laser pulse. A transverse electromagnetic wave with frequency in the terahertz range is generated due to the presence of the magnetic field. Further, two-dimensional simulations using XOOPIC code show that the THz fields generated in plasma are transmitted into vacuum. The fields obtained via simulation study are found to be compatible with those obtained from the numerical model.
Geometric and Electromagnetic Aspects of Fusion Pore Making
Darya Apushkinskaya; Evgeny Apushkinsky; Bernhelm Booss-Bavnbek; Martin Koch
2010-04-29T23:59:59.000Z
For regulated exocytosis, we model the morphology and dynamics of the making of the fusion pore or porosome as a cup-shaped lipoprotein structure (a dimple or pit) on the cytosol side of the plasma membrane. We describe the forming of the dimple by a free boundary problem. We discuss the various forces acting and analyze the magnetic character of the wandering electromagnetic field wave produced by intracellular spatially distributed pulsating (and well observed) release and binding of calcium ions anteceding the bilayer membrane vesicle fusion of exocytosis. Our approach explains the energy efficiency of the observed dimple forming prior to hemifusion and fusion pore, and the observed flickering in secretion. It provides a frame to relate characteristic time length of exocytosis to the frequency, amplitude and direction of propagation of the underlying electromagnetic field wave.
Electromagnetic reactions on light nuclei
Sonia Bacca; Saori Pastore
2014-07-13T23:59:59.000Z
Electromagnetic reactions on light nuclei are fundamental to advance our understanding of nuclear structure and dynamics. The perturbative nature of the electromagnetic probes allows to clearly connect measured cross sections with the calculated structure properties of nuclear targets. We present an overview on recent theoretical ab-initio calculations of electron-scattering and photonuclear reactions involving light nuclei. We encompass both the conventional approach and the novel theoretical framework provided by chiral effective field theories. Because both strong and electromagnetic interactions are involved in the processes under study, comparison with available experimental data provides stringent constraints on both many-body nuclear Hamiltonians and electromagnetic currents. We discuss what we have learned from studies on electromagnetic observables of light nuclei, starting from the deuteron and reaching up to nuclear systems with mass number A=16.
The parametric decay of Alfven waves into shear Alfven waves and dust lower hybrid waves
Jamil, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Crescent Model School Shadman, Lahore 54000 (Pakistan); Shah, H. A.; Zubia, K.; Zeba, I.; Uzma, Ch. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Salimullah, M. [Department of Physics, Government College University, Lahore 54000 (Pakistan); Department of Physics, Jahangirnagar University, Savar, Dhaka 1342 (Bangladesh)
2010-07-15T23:59:59.000Z
The parametric decay instability of Alfven wave into low-frequency electrostatic dust-lower-hybrid and electromagnetic shear Alfven waves has been investigated in detail in a dusty plasma in the presence of external/ambient uniform magnetic field. Magnetohydrodynamic fluid equations of plasmas have been employed to find the linear and nonlinear response of the plasma particles for this three-wave nonlinear coupling in a dusty magnetoplasma. Here, relatively high frequency electromagnetic Alfven wave has been taken as the pump wave. It couples with other two low-frequency internal possible modes of the dusty magnetoplasma, viz., the dust-lower-hybrid and shear Alfven waves. The nonlinear dispersion relation of the dust-lower-hybrid wave has been solved to obtain the growth rate of the parametric decay instability. The growth rate is maximum for small value of external magnetic field B{sub s}. It is noticed that the growth rate is proportional to the unperturbed electron number density n{sub oe}.
Nucleon Electromagnetic Form Factors
Marc Vanderhaeghen; Charles Perdrisat; Vina Punjabi
2007-10-01T23:59:59.000Z
There has been much activity in the measurement of the elastic electromagnetic proton and neutron form factors in the last decade, and the quality of the data has greatly improved by performing double polarization experiments, in comparison with previous unpolarized data. Here we review the experimental data base in view of the new results for the proton, and neutron, obtained at JLab, MAMI, and MIT-Bates. The rapid evolution of phenomenological models triggered by these high-precision experiments will be discussed, including the recent progress in the determination of the valence quark generalized parton distributions of the nucleon, as well as the steady rate of improvements made in the lattice QCD calculations.
Gravitational waves and gamma-ray bursts
Alessandra Corsi; for the LIGO Scientific Collaboration; for the Virgo Collaboration
2012-05-11T23:59:59.000Z
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.
6, 52315250, 2006 Radiative properties
Paris-Sud XI, Université de
the short- wave (SW) and longwave (LW) cloud radiative effects (CRE), but the impact is small: 0.02 W m-2 tests are conducted to evaluate the impact that5 such an over-layer would have on the radiative effects, terrestrial) radiation. The SW "albedo" effect brings about cooling and the LW "greenhouse" effect warming
Mercier, Matthieu J; Mathur, Manikandan; Gostiaux, Louis; Peacock, Thomas; Dauxois, Thierry
2015-01-01T23:59:59.000Z
We present the results of a combined experimental and numerical study of the generation of internal waves using the novel internal wave generator design of Gostiaux et al. (2007). This mechanism, which involves a tunable source comprised of oscillating plates, has so far been used for a few fundamental studies of internal waves, but its full potential has yet to be realized. Our studies reveal that this approach is capable of producing a wide variety of two-dimensional wave fields, including plane waves, wave beams and discrete vertical modes in finite-depth stratifications. The effects of discretization by a finite number of plates, forcing amplitude and angle of propagation are investigated, and it is found that the method is remarkably efficient at generating a complete wave field despite forcing only one velocity component in a controllable manner. We furthermore find that the nature of the radiated wave field is well predicted using Fourier transforms of the spatial structure of the wave generator.
Radio frequency communication system utilizing radiating transmission lines
Struven, Warren C. (San Carlos, CA)
1984-01-01T23:59:59.000Z
A radio communication system for use in tunnels, mines, buildings or other shielded locations in which a pair of radiating transmission lines (30), (31) extend through such location in spaced coextensive relation to each other. Each transmission line (30), (31) has at least one unidirectional amplifier (32), (33) interposed therein with the sense of the unidirectional amplifier (32) of one transmission line (30) being opposite to the sense of the unidirectional amplifier (33) of the other transmission line (31). Each of the amplifiers (32), (33) has a gain which is less than the coupling loss between the transmission lines (30), (31). Two or more mobile transceivers (35) in the location served by the system are coupled to the transmission lines (30), (31) by electromagnetic wave propagation in space in order to communicate directly with each other at a given radio frequency within the frequency range of the system.
Nuclear electromagnetic charge and current operators in Chiral EFT
Girlanda, Luca [Università del Salento; Marcucci, Laura Elisa [Univ. Pisa; Pastore, Saori [Department of Physics and Astronomy, University of South Carolina, Columbia, SC; Piarulli, Maria [Department of Physics, Old Dominion University, Norfolk, VA; Schiavilla, Rocco [Old Dominion U., JLAB; Viviani, Michele
2013-08-01T23:59:59.000Z
We describe our method for deriving the nuclear electromagnetic charge and current operators in chiral perturbation theory, based on time-ordered perturbation theory. We then discuss possible strategies for fixing the relevant low-energy constants, from the magnetic moments of the deuteron and of the trinucleons, and from the radiative np capture cross sections, and identify a scheme which, partly relying on {Delta} resonance saturation, leads to a reasonable pattern of convergence of the chiral expansion.
Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)
PANDA Collaboration; W. Erni; I. Keshelashvili; B. Krusche; M. Steinacher; Y. Heng; Z. Liu; H. Liu; X. Shen; O. Wang; H. Xu; J. Becker; F. Feldbauer; F. -H. Heinsius; T. Held; H. Koch; B. Kopf; M. Pelizaeus; T. Schroeder; M. Steinke; U. Wiedner; J. Zhong; A. Bianconi; M. Bragadireanu; D. Pantea; A. Tudorache; V. Tudorache; M. De Napoli; F. Giacoppo; G. Raciti; E. Rapisarda; C. Sfienti; E. Bialkowski; A. Budzanowski; B. Czech; M. Kistryn; S. Kliczewski; A. Kozela; P. Kulessa; K. Pysz; W. Schaefer; R. Siudak; A. Szczurek; W. Czy. zycki; M. Domagala; M. Hawryluk; E. Lisowski; F. Lisowski; L. Wojnar; D. Gil; P. Hawranek; B. Kamys; St. Kistryn; K. Korcyl; W. Krzemien; A. Magiera; P. Moskal; Z. Rudy; P. Salabura; J. Smyrski; A. Wronska; M. Al-Turany; I. Augustin; H. Deppe; H. Flemming; J. Gerl; K. Goetzen; R. Hohler; D. Lehmann; B. Lewandowski; J. Luehning; F. Maas; D. Mishra; H. Orth; K. Peters; T. Saito; G. Schepers; C. J. Schmidt; L. Schmitt; C. Schwarz; B. Voss; P. Wieczorek; A. Wilms; K. -T. Brinkmann; H. Freiesleben; R. Jaekel; R. Kliemt; T. Wuerschig; H. -G. Zaunick; V. M. Abazov; G. Alexeev; A. Arefiev; V. I. Astakhov; M. Yu. Barabanov; B. V. Batyunya; Yu. I. Davydov; V. Kh. Dodokhov; A. A. Efremov; A. G. Fedunov; A. A. Feshchenko; A. S. Galoyan; S. Grigoryan; A. Karmokov; E. K. Koshurnikov; V. Ch. Kudaev; V. I. Lobanov; Yu. Yu. Lobanov; A. F. Makarov; L. V. Malinina; V. L. Malyshev; G. A. Mustafaev; A. Olshevski; M. A. . Pasyuk; E. A. Perevalova; A. A. Piskun; T. A. Pocheptsov; G. Pontecorvo; V. K. Rodionov; Yu. N. Rogov; R. A. Salmin; A. G. Samartsev; M. G. Sapozhnikov; A. Shabratova; G. S. Shabratova; A. N. Skachkova; N. B. Skachkov; E. A. Strokovsky; M. K. Suleimanov; R. Sh. Teshev; V. V. Tokmenin; V. V. Uzhinsky; A. S. Vodopianov; S. A. Zaporozhets; N. I. Zhuravlev; A. G. Zorin; D. Branford; K. Foehl; D. Glazier; D. Watts; P. Woods; W. Eyrich; A. Lehmann; A. Teufel; S. Dobbs; Z. Metreveli; K. Seth; B. Tann; A. Tomaradze; D. Bettoni; V. Carassiti; A. Cecchi; P. Dalpiaz; E. Fioravanti; I. Garzia; M. Negrini; M. Savri`e; G. Stancari; B. Dulach; P. Gianotti; C. Guaraldo; V. Lucherini; E. Pace; A. Bersani; M. Macri; M. Marinelli; R. F. Parodi; I. Brodski; W. Doering; P. Drexler; M. Dueren; Z. Gagyi-Palffy; A. Hayrapetyan; M. Kotulla; W. Kuehn; S. Lange; M. Liu; V. Metag; M. Nanova; R. Novotny; C. Salz; J. Schneider; P. Schoenmeier; R. Schubert; S. Spataro; H. Stenzel; C. Strackbein; M. Thiel; U. Thoering; S. Yang; T. Clarkson; E. Cowie; E. Downie; G. Hill; M. Hoek; D. Ireland; R. Kaiser; T. Keri; I. Lehmann; K. Livingston; S. Lumsden; D. MacGregor; B. McKinnon; M. Murray; D. Protopopescu; G. Rosner; B. Seitz; G. Yang; M. Babai; A. K. Biegun; A. Bubak; E. Guliyev; V. S. Jothi; M. Kavatsyuk; H. Loehner; J. Messchendorp; H. Smit; J. C. van der Weele; F. Garcia; D. -O. Riska; M. Buescher; R. Dosdall; R. Dzhygadlo; A. Gillitzer; D. Grunwald; V. Jha; G. Kemmerling; H. Kleines; A. Lehrach; R. Maier; M. Mertens; H. Ohm; D. Prasuhn; T. Randriamalala; J. Ritman; M. Roeder; T. Stockmanns; P. Wintz; P. Wuestner; J. Kisiel; S. Li; Z. Li; Z. Sun; H. Xu; S. Fissum; K. Hansen; L. Isaksson; M. Lundin; B. Schroeder; P. Achenbach; M. C. Mora Espi; J. Pochodzalla; S. Sanchez; A. Sanchez-Lorente; V. I. Dormenev; A. A. Fedorov; M. V. Korzhik; O. V. Missevitch; V. Balanutsa; V. Chernetsky; A. Demekhin; A. Dolgolenko; P. Fedorets; A. Gerasimov; V. Goryachev; A. Boukharov; O. Malyshev; I. Marishev; A. Semenov; C. Hoeppner; B. Ketzer; I. Konorov; A. Mann; S. Neubert; S. Paul; Q. Weitzel; A. Khoukaz; T. Rausmann; A. Taeschner; J. Wessels; R. Varma; E. Baldin; K. Kotov; S. Peleganchuk; Yu. Tikhonov; J. Boucher; T. Hennino; R. Kunne; S. Ong; J. Pouthas; B. Ramstein; P. Rosier; M. Sudol; J. Van de Wiele; T. Zerguerras; K. Dmowski; R. Korzeniewski; D. Przemyslaw; B. Slowinski; G. Boca; A. Braghieri; S. Costanza; A. Fontana; P. Genova; L. Lavezzi; P. Montagna; A. Rotondi; N. I. Belikov; A. M. Davidenko; A. A. Derevschikov; Y. M. Goncharenko; V. N. Grishin; V. A. Kachanov; D. A. Konstantinov; V. A. Kormilitsin; V. I. Kravtsov; Y. A. Matulenko; Y. M. Melnik; A. P. Meschanin; N. G. Minaev; V. V. Mochalov; D. A. Morozov; L. V. Nogach; S. B. Nurushev; A. V. Ryazantsev; P. A. Semenov; L. F. Soloviev; A. V. Uzunian; A. N. Vasiliev; A. E. Yakutin; T. Baeck; B. Cederwall; C. Bargholtz; L. Geren; P. E. Tegner; S. Belostotski; G. Gavrilov; A. Itzotov; A. Kisselev; P. Kravchenko; S. Manaenkov; O. Miklukho; Y. Naryshkin; D. Veretennikov; V. Vikhrov; A. Zhadanov; L. Fava; D. Panzieri; D. Alberto; A. Amoroso; E. Botta; T. Bressani; S. Bufalino; M. P. Bussa; L. Busso; F. De Mori; M. Destefanis; L. Ferrero; A. Grasso; M. Greco; T. Kugathasan; M. Maggiora; S. Marcello; G. Serbanut; S. Sosio; R. Bertini; D. Calvo; S. Coli; P. De Remigis; A. Feliciello; A. Filippi; G. Giraudo; G. Mazza; A. Rivetti
2008-10-07T23:59:59.000Z
This document presents the technical layout and the envisaged performance of the Electromagnetic Calorimeter (EMC) for the PANDA target spectrometer. The EMC has been designed to meet the physics goals of the PANDA experiment, which is being developed for the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, Germany. The performance figures are based on extensive prototype tests and radiation hardness studies. The document shows that the EMC is ready for construction up to the front-end electronics interface.
Colliding axisymmetric pp-waves
B. V. Ivanov
1997-10-21T23:59:59.000Z
An exact solution is found describing the collision of axisymmetric pp-waves with M=0. They are impulsive in character and their coordinate singularities become point curvature singularities at the boundaries of the interaction region. The solution is conformally flat. Concrete examples are given, involving an ultrarelativistic black hole against a burst of pure radiation or two colliding beam- like waves.
Frank G. Borg; Ismo Hakala; Jukka Määttälä
2007-12-24T23:59:59.000Z
We present a summary of the basic properties of the radio wave generation, propagation and reception, with a special attention to the gigahertz bandwidth region which is of interest for wireless sensor networks. We also present some measurement results which use the so-called RSSI indicator in order to track how the field strength varies with position and distance of the transceivers. We hope the paper may be useful to anyone who looks for a quick review of the fundamentals of electromagnetic theory with application to antennas.
Scattering of an ultrashort electromagnetic pulse in a plasma
Astapenko, V. A. [Moscow Institute of Physics and Technology (Russian Federation)
2011-11-15T23:59:59.000Z
An analytic approach is developed to describing how ultrashort electromagnetic pulses with a duration of one period or less at the carrier frequency are scattered in a plasma. Formulas are derived to calculate and analyze the angular and spectral probabilities of radiation scattering via two possible mechanisms-Compton and transition radiation channels-throughout the entire pulse. Numerical simulations were carried out for a Gaussian pulse. The effect of the phase of the carrier frequency relative to the pulse envelope on the scattering parameters is investigated.
Interaction of gravitational waves with matter
A. Cetoli; C. J. Pethick
2011-10-03T23:59:59.000Z
We develop a unified formalism for describing the interaction of gravitational waves with matter that clearly separates the effects of general relativity from those due to interactions in the matter. Using it, we derive a general expression for the dispersion of gravitational waves in matter in terms of correlation functions for the matter in flat spacetime. The self energy of a gravitational wave is shown to have contributions analogous to the paramagnetic and diamagnetic contributions to the self energy of an electromagnetic wave. We apply the formalism to some simple systems - free particles, an interacting scalar field, and a fermionic superfluid.
Radiation and Dynamics of Dust Particle
Jozef Klacka
2002-09-23T23:59:59.000Z
Relativistically covariant form of equation of motion for arbitrarily shaped dust particle (neutral in charge) under the action of electromagnetic radiation is derived -- emission, scattering and absorption of radiation is considered. The result is presented in the form of optical quantities used in optics of dust particles. The obtained equation of motion represents a generalization of the Poynting-Robertson (P-R) effect, which is standardly used in orbital evolution of dust particles in astrophysics. Simultaneous action of electromagnetic radiation and gravitational fields of the central body -- star -- on the motion of the particle is discussed.
Method for microbeam radiation therapy
Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.
1994-08-16T23:59:59.000Z
A method is disclosed of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation. The dose is in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue. No Drawings
Spacetime algebra as a powerful tool for electromagnetism
Justin Dressel; Konstantin Y. Bliokh; Franco Nori
2014-12-03T23:59:59.000Z
We present a comprehensive introduction to spacetime algebra that emphasizes its practicality and power as a tool for the study of electromagnetism. We carefully develop this natural (Clifford) algebra of the Minkowski spacetime geometry, with a particular focus on its intrinsic (and often overlooked) complex structure. Notably, the scalar imaginary that appears throughout the electromagnetic theory properly corresponds to the unit 4-volume of spacetime itself, and thus has physical meaning. The electric and magnetic fields are combined into a single complex and frame-independent bivector field, which generalizes the Riemann-Silberstein complex vector that has recently resurfaced in studies of the single photon wavefunction. The complex structure of spacetime also underpins the emergence of electromagnetic waves, circular polarizations, the normal variables for canonical quantization, the distinction between electric and magnetic charge, complex spinor representations of Lorentz transformations, and the dual (electric-magnetic field exchange) symmetry that produces helicity conservation in vacuum fields. This latter symmetry manifests as an arbitrary global phase of the complex field, motivating the use of a complex vector potential, along with an associated transverse and gauge-invariant bivector potential, as well as complex (bivector and scalar) Hertz potentials. Our detailed treatment aims to encourage the use of spacetime algebra as a readily available and mature extension to existing vector calculus and tensor methods that can greatly simplify the analysis of fundamentally relativistic objects like the electromagnetic field.
High-frequency surface wave pumped He-Ne laser
Moutoulas, C.; Moisan, M.; Bertrand, L.; Hubert, J.; Lachambre, J.L.; Ricard, A.
1985-02-15T23:59:59.000Z
A new electrodeless He-Ne laser using a plasma produced by an electromagnetic surface wave as the active medium is described. Gain measurements are reported as a function of the pump wave frequency from 200 to 915 MHz. The dependence of laser performance on the gas mixture and pressure is also presented.
Energy Content of Colliding Plane Waves using Approximate Noether Symmetries
M. Sharif; Saira Waheed
2011-09-19T23:59:59.000Z
This paper is devoted to study the energy content of colliding plane waves using approximate Noether symmetries. For this purpose, we use approximate Lie symmetry method of Lagrangian for differential equations. We formulate the first-order perturbed Lagrangian for colliding plane electromagnetic and gravitational waves. It is shown that in both cases, there does not exist
Waves in Nature, Lasers to Tsumanis and Beyond
LLNL - University of California Television
2009-09-01T23:59:59.000Z
Waves are everywhere. Microwaves, laser beams, music, tsunamis. Electromagnetic waves emanating from the Big Bang fill the universe. Learn about the similarities and difference in all of these wavy phenomena with Ed Moses and Rick Sawicki, Lawrence Livermore National Laboratory scientists Series: Science on Saturday [10/2006] [Science] [Show ID: 11541
ECE 444: Antennas and Radiation Pre-requisites
Schumacher, Russ
effect in good conductors - Can analyze lossless and lossy transmission lines with different terminations Electromagnetic Field Energy and Radiation - Can apply Poynting's theorem to discuss power balance - Can use retarded electromagnetic potentials to find electric and magnetic fields due to high
Classification of Electromagnetic and Gravitational Hopfions by Algebraic Type
Amy Thompson; Alexander Wickes; Joe Swearngin; Dirk Bouwmeester
2015-05-02T23:59:59.000Z
We extend the definition of hopfions to include a class of spin-$h$ fields and use this to introduce the electromagnetic and gravitational hopfions of different algebraic types. The fields are constructed through the Penrose contour integral transform, thus the singularities of the generating functions are directly related to the geometry of the resulting physical fields. We discuss this relationship and how the topological structure of the fields is related to the Robinson congruence. Since the topology appears in the lines of force for both electromagnetism and gravity, the gravito-electromagnetic formalism is used to analyze the gravitational hopfions and describe the time evolution of their tendex and vortex lines. The correspondence between fields of different spin results in analogous configurations based on the same topological structure. The null and type N fields propagate at the speed of light, while the non-null and type D fields radiate energy outward from the center. Finally we discuss the type III gravitational hopfion, which has no direct electromagnetic analog, but find that it still exhibits some of the characteristic features common to the other hopfion fields.
Dynamics of electromagnetic solitons in a relativistic plasma
Mancic, Ana; Hadzievski, Ljupco; Skoric, Milos M. [Department of Physics, Faculty of Sciences and Mathematics, University of Nis, P. O. B. 224, 18001 Nis (Serbia and Montenegro); Vinca Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia and Montenegro); National Institute for Fusion Science, Toki, 509-5292 (Japan)
2006-05-15T23:59:59.000Z
Dynamical features of one-dimensional electromagnetic solitons formed in a relativistic interaction of a linearly polarized laser light with underdense cold plasma are investigated. The relativistic Lorentz force in an intense laser light pushes electrons into longitudinal motion, generating coupled longitudinal-transverse waves. In a weakly relativistic approximation these modes are well described by the generalized nonlinear Schroedinger type of equation, with two extra nonlocal terms. Here, an original analytical solution for a moving electromagnetic soliton is derived in an implicit form. For an isolated soliton, our analysis shows that the motion downshifts the soliton eigenfrequency and decreases its amplitude. The effect of the soliton velocity on the stability is analytically predicted and checked numerically. Results show shifting of the stability region toward larger amplitudes in comparison to the standing soliton case. Rich dynamics with examples of (un)stable soliton propagation and breather creation and formation of unstable cusp-type structures is exposed numerically.
Laser photon merging in an electromagnetic field inhomogeneity
Holger Gies; Felix Karbstein; Rashid Shaisultanov
2014-08-13T23:59:59.000Z
We study the effect of laser photon merging, or equivalently high harmonic generation, in the quantum vacuum subject to inhomogeneous electromagnetic fields. Such a process is facilitated by the effective nonlinear couplings arising from charged particle-antiparticle fluctuations in the quantum vacuum subject to strong electromagnetic fields. We derive explicit results for general kinematic and polarization configurations involving optical photons. Concentrating on merged photons in reflected channels which are preferable in experiments for reasons of noise suppression, we demonstrate that photon merging is typically dominated by the competing nonlinear process of quantum reflection, though appropriate polarization and signal filtering could specifically search for the merging process. As a byproduct, we devise a novel systematic expansion of the photon polarization tensor in plane wave fields.
Radiation and evolution of small relativistic dipole in QED
B. Blok
2003-05-26T23:59:59.000Z
We study in the quasiclassical approximation the radiation reaction and its influence on the space-time evolution for the small relativistic dipole moving in a constant external electromagnetic field in QED.
Role of Higher Multipole Excitations in the Electromagnetic Dissociation of One Neutron Halo Nuclei
R. Chatterjee; L. Fortunato; A. Vitturi
2007-12-20T23:59:59.000Z
We investigate the role of higher multipole excitations in the electromagnetic dissociation of one-neutron halo nuclei within two different theoretical models -- a finite range distorted wave Born approximation and another in a more analytical method with a finite range potential. We also show, within a simple picture, how the presence of a weakly bound state affects the breakup cross section.
Well-posedness for Systems Representing Electromagnetic/Acoustic Wavefront Interaction
interrogation.) In one such class of electromagnetic interrogation techniques, one uses a superconductive (also and applications for techniques which employ superconductive metal backings and standing acoustic waves as re are absorbing on the left (z = 0) and superconductive on the right (z = 1). We use general initial conditions
Electromagnetic-gravitational cross-sections in external electromagnetic fields
Long, H N; Tran, T A; Tuan, T A; Long, Hoang Ngoc; Van Soa, Dang; Tran, Tuan A; Tuan, Tran Anh
1994-01-01T23:59:59.000Z
The classical processes: the conversion of photons into gravitons in the static electromagnetic fields are considered by using Feynman perturbation techniques. The differential cross sections are presented for the conversion in the electric field of the flat condesor and the magnetic field of the selenoid. A numerical evaluation shows that the cross sections may have the observable value in the present technical scenario.
Hanson, George
in radiofrequency-terahertz heating of nanoparticles G. W. Hanson,1,a) R. C. Monreal,2 and S. P. Apell3 1 Department on the absorption of electromagnetic radiation by metallic nanoparticles in the radio and far infrared frequency by which nonmagnetic metallic nanoparticles can absorb low frequency radiation, including both classical
Electromagnetic design considerations for fast acting controllers
Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)
1996-07-01T23:59:59.000Z
Electromagnetic design considerations for fast acting controllers in a power system is introduced and defined. A distinction is made in relation to the more commonly understood system control design necessary for damping electromechanical oscillations using stability programs and eigenanalysis. Electromagnetic eigenanalysis tools have limited availability and are consequently rarely used. Electromagnetic transients programs (emtp) on the other hand are widely used and a procedure for undertaking electromagnetic control design of fast acting controllers in a power system using emtp is presented.
Orthogonal-Phase-Velocity Propagation of Electromagnetic Plane Waves
Tom G. Mackay; Akhlesh Lakhtakia
2005-11-30T23:59:59.000Z
In an isotropic, homogeneous, nondissipative, dielectric-magnetic medium that is simply moving with respect to an inertial reference frame, planewave solutions of the Maxwell curl postulates can be such that the phase velocity and the time-averaged Poynting vector are mutually orthogonal. Orthogonal-phase-velocity propagation thus adds to the conventional positive-phase-velocity propagation and the recently discovered negative-phase-velocity propagation that is associated with the phenomenon of negative refraction.
Subluminal and Superluminal Electromagnetic Waves and the Lepton Mass Spectrum
Rodríguez, W A
1996-01-01T23:59:59.000Z
Maxwell equation $\\dirac F = 0$ for $F \\in \\sec \\bwe^2 M \\subset \\sec \\clif (M)$, where $\\clif (M)$ is the Clifford bundle of differential forms, have subluminal and superluminal solutions characterized by $F^2 \
Responses of an articulated loading platform in waves and currents
Ran, Zhihuang
1993-01-01T23:59:59.000Z
The responses of an articulated loading platform (ALP) in regular and irregular unidirectional waves (with or without currents) are investigated both in frequency and time domain. The first- and second-order wave diffraction radiation are solved...
Structurally Electromagnetic Formation Flight (EMFF)
de Weck, Olivier L.
Structurally connected secondary mirror EMFF secondary mirror EMFF Design Electromagnetic Formation for a smaller, simpler system. ÂµEMFF investigates the use of conventional conductors, capacitors, and solar propellants that often limit lifetime, the EMFF system uses solar power to energize a magnetic field
Electromagnetic scattering from grassland Part II: Measurement and modeling results
Stiles, James Marion; Ulaby, F. T.; Sarabandi, K.
2000-01-01T23:59:59.000Z
-InvestigatoronmanyprojectssponsoredbyNASA,JPL,ARO,ONR,ARL, and GM all related in one way or the other to microwave and millimeter wave radar remote sensing. He has published many book chapters and more than 80 papers in refereed journals on electromagnetic scattering, random media modeling, microwave measurement...LecturerAwardfromtheGerman Federal Ministry for Education, Science, and Technology. FawwazT.Ulaby(M’68–SM’74–F’80)receivedthe B.S.degreeinphysicsfromtheAmericanUniversity of Beirut, Lebanon, in 1964, and the M.S.E.E. and Ph.D.degreesinelectricalengineeringfromtheUni- versity...
Modified definition of group velocity and electromagnetic energy conservation equation
Changbiao Wang
2015-01-19T23:59:59.000Z
The classical definition of group velocity has two flaws: (a) the group velocity can be greater than the phase velocity 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.
Electromagnetic pulses which have a zero momentum frame
John Lekner
2003-04-08T23:59:59.000Z
One set of the Ziolkowski family of exact solutions of the wave equation are shown to represent pulses propagating with momentum smaller than energy/c. This is explicitly demonstrated for special cases by calculating the total electromagnetic momentum and energy. Since the ratio of momentum to energy is a constant smaller than 1/c, there exists a Lorentz transformation to a frame in which the total momentum is zero. In the zero-momentum frame the fields are those of an annular pulse converging onto or diverging from a focal region.
Kioussis, Nicholas
. 1 Chapter 30: Quantum Physics 9. The tungsten filament in a standard light bulb can be considered frequency is that of infrared electromagnetic radiation, the light bulb radiates more energy in the infrared
Santolik, Ondrej
be related to power line harmonic radiation (PLHR, an electromagnetic radiation from electric power systemsMagnetospheric line radiation event observed simultaneously on board Cluster 1, Cluster 2., O. Santolík, M. Parrot, and J. S. Pickett (2012), Magnetospheric line radiation event observed
An Obliquely Propagating Electromagnetic Drift Instability in the Lower Hybrid Frequency Range
Hantao Ji; Russell Kulsrud; William Fox; Masaaki Yamada
2005-06-10T23:59:59.000Z
By employing a local two-fluid theory, we investigate an obliquely propagating electromagnetic instability in the lower hybrid frequency range driven by cross-field current or relative drifts between electrons and ions. The theory self-consistently takes into account local cross-field current and accompanying pressure gradients. It is found that the instability is caused by reactive coupling between the backward propagating whistler (fast) waves in the moving electron frame, and the forward propagating sound (slow) waves in the ion frame when the relative drifts are large. The unstable waves we consider propagate obliquely to the unperturbed magnetic field and have mixed polarization with significant electromagnetic components. A physical picture of the instability emerges in the limit of large wave number characteristic of the local approximation. The primary positive feedback mechanism is based on reinforcement of initial electron density perturbations by compression of electron fluid via induced Lorentz force. The resultant waves are qualitatively consistent with the measured electromagnetic fluctuations in reconnecting current sheet in a laboratory plasma.
Khan, S. A. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Ayub, M. K. [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Pohang University of Science and Technology (POSTECH), Pohang, Gyunbuk 790-784 (Korea, Republic of); Ahmad, Ali [National Centre for Physics, Quaid-i-Azam University Campus, Islamabad 45320 (Pakistan); Theoretical Plasma Physics Division, PINSTECH, P. O. Nilore, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology, Islamabad 44000 (Pakistan)
2012-10-15T23:59:59.000Z
Quantum plasma oscillations are studied in a strongly magnetized, ultra-dense plasma with degenerate electrons and positrons. The dispersive role of electron and positron quantum effects on low frequency (in comparison to electron cyclotron frequency) shear electromagnetic wave is investigated by employing hydrodynamic formulation. In the presence of ions, the density balance changes, and the electromagnetic wave (with frequency lower than the ion cyclotron frequency) is shown to couple with electrostatic ion mode under certain conditions. For such low frequency waves, it is also seen that the contribution of electron and positron degeneracy pressure is dominant as compared to their diffraction effects. The results are analyzed numerically for illustrative purpose pointing out their relevance to the dense laboratory (e.g., super-intense laser-dense matter interactions) and astrophysical plasmas.
Long-term Electro-Magnetic Robustness of Integrated Circuits: EMRIC research project
Paris-Sud XI, Université de
EMR in the scientific community and will contribute to develop EMR qualification procedures, EMR) and their low electromagnetic radiation (emission) that could disturb neighbour equipment. Ensuring both low. Integrating EMR models to simulation flow and developing EMR qualification procedures will help IC designer
Conversion of electromagnetic energy in Z-pinch process of single planar wire arrays at 1.5 MA
Liangping, Wang; Mo, Li; Juanjuan, Han; Ning, Guo [Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Key State Laboratory of Simulation and Effect for Intense Pulse Radiation, Xi'an 710024 (China); Jian, Wu [Xi'an Jiaotong University, Xi'an 710049 (China); Aici, Qiu [Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Xi'an Jiaotong University, Xi'an 710049 (China)
2014-06-15T23:59:59.000Z
The electromagnetic energy conversion in the Z-pinch process of single planar wire arrays was studied on Qiangguang generator (1.5 MA, 100?ns). Electrical diagnostics were established to monitor the voltage of the cathode-anode gap and the load current for calculating the electromagnetic energy. Lumped-element circuit model of wire arrays was employed to analyze the electromagnetic energy conversion. Inductance as well as resistance of a wire array during the Z-pinch process was also investigated. Experimental data indicate that the electromagnetic energy is mainly converted to magnetic energy and kinetic energy and ohmic heating energy can be neglected before the final stagnation. The kinetic energy can be responsible for the x-ray radiation before the peak power. After the stagnation, the electromagnetic energy coupled by the load continues increasing and the resistance of the load achieves its maximum of 0.6–1.0 ? in about 10–20?ns.
Comment on 'Kinetic theory of surface waves in plasma jets' [Phys. Plasmas 9, 701 (2002)
Lee, Hee J. [Department of Physics, Hanyang University, Seoul 133-791 (Korea, Republic of)
2005-09-15T23:59:59.000Z
It is shown that the dispersion relation of electromagnetic surface waves propagating on the interface between a vacuum and drifting Maxwellian plasmas derived in recent work [Phys. Plasmas 9, 701 (2002)] is incorrect. Correct electromagnetic and electrostatic dispersion relations are obtained.
Crozier, Richard Carson
2014-06-30T23:59:59.000Z
Combined electrical and structural models of five types of permanent magnet linear electrical machines suitable for direct-drive power take-off on wave energy applications are presented. Electromagnetic models were ...
Chaotic Emission from Electromagnetic Systems Considering Self-Interaction
Fernando Kokubun; Vilson T. Zanchin
2006-05-02T23:59:59.000Z
The emission of electromagnetic waves from a system described by the H\\'enon-Heiles potential is studied in this work. The main aim being to analyze the behavior of the system when the damping term is included explicitly into the equations of motion. Energy losses at the chaotic regime and at the regular regime are compared. The results obtained here are similar to the case of gravitational waves emission, as long we consider only the energy loss. The main difference being that in the present work the energy emitted is explicitly calculated solving the equation of motion without further approximations. It is expected that the present analysis may be useful when studying the analogous problem of dissipation in gravitational systems.
Breit-Wheeler process in very short electromagnetic pulses
A. I. Titov; B. Kampfer; H. Takabe; A. Hosaka
2013-03-26T23:59:59.000Z
The generalized Breit-Wheeler process, i.e. the emission of $e^+e^-$ pairs off a probe photon propagating through a polarized short-pulsed electromagnetic (e.g.\\ laser) wave field, is analyzed. We show that the production probability is determined by the interplay of two dynamical effects. The first one is related to the shape and duration of the pulse and the second one is the non-linear dynamics of the interaction of $e^\\pm$ with the strong electromagnetic field. The first effect manifests itself most clearly in the weak-field regime, where the small field intensity is compensated by the rapid variation of the electromagnetic field in a limited space-time region, which intensifies the few-photon events and can enhance the production probability by orders of magnitude compared to an infinitely long pulse. Therefore, short pulses may be considered as a powerful amplifier. The non-linear dynamics in the multi-photon Breit-Wheeler regime plays a decisive role at large field intensities, where effects of the pulse shape and duration are less important. In the transition regime, both effects must be taken into account simultaneously. We provide suitable expressions for the $e^+e^-$ production probability for kinematic regions which can be used in transport codes.
Laminated electromagnetic pump stator core
Fanning, A.W.
1995-08-08T23:59:59.000Z
A stator core for an electromagnetic pump includes a plurality of circumferentially abutting tapered laminations extending radially outwardly from a centerline axis to collectively define a radially inner bore and a radially outer circumference. Each of the laminations includes radially inner and outer edges and has a thickness increasing from the inner edge toward the outer edge to provide a substantially continuous path adjacent the circumference. This pump is used in nuclear fission reactors. 19 figs.
Electromagnetism Tutorial (Tutorial de Eletromagnetismo)
Dantas, Christine C
2009-01-01T23:59:59.000Z
The present tutorial aims at covering the fundamentals of electromagnetism, in a condensed and clear manner. Some solved and proposed exercises have been included. The reader is assumed to have knowledge of basic electricity, partial derivatives and multiple integrals. ----- O presente tutorial visa cobrir os fundamentos do eletromagnetismo, de forma condensada e clara. Alguns exercicios resolvidos e propostos foram incluidos. Assume-se conhecimento de eletricidade basica, derivadas parciais e integrais multiplas.
Thermal radiation from an accretion disk
F. V. Prigara
2004-01-20T23:59:59.000Z
An effect of stimulated radiation processes on thermal radiation from an accretion disk is considered. The radial density waves triggering flare emission and producing quasi-periodic oscillations in radiation from an accretion disk are discussed. It is argued that the observational data suggest the existence of the weak laser sources in a two-temperature plasma of an accretion disk.
Poynting-vector based method for determining the bearing and location of electromagnetic sources
Simons, David J. (Modesto, CA); Carrigan, Charles R. (Tracy, CA); Harben, Philip E. (Livermore, CA); Kirkendall, Barry A. (Golden, CO); Schultz, Craig A. (Danville, CA)
2008-10-21T23:59:59.000Z
A method and apparatus is utilized to determine the bearing and/or location of sources, such as, alternating current (A.C.) generators and loads, power lines, transformers and/or radio-frequency (RF) transmitters, emitting electromagnetic-wave energy for which a Poynting-Vector can be defined. When both a source and field sensors (electric and magnetic) are static, a bearing to the electromagnetic source can be obtained. If a single set of electric (E) and magnetic (B) sensors are in motion, multiple measurements permit location of the source. The method can be extended to networks of sensors allowing determination of the location of both stationary and moving sources.
Derivation of Gell-Mann-Nishijima formula from the electromagnetic field modes of a hadron
Huai-yang Cui
2010-07-23T23:59:59.000Z
When an electron probes another elementary particle Q, the wave function of the electron can be separated into two independent parts, the first part represents the electronic motion, the second part represents the electromagnetic field mode around the particle Q. In analogy with optical modes $TEM_{nlm}$ for a laser resonator, when the electromagnetic field around the particle Q forms into a mode, the quantum numbers of the mode satisfy the Gell-Mann-Nishijima formula, these quantum numbers are recognized as the charge number, baryon number and strangeness number. The modes are used as a visual model to understand the abstract baryon number and strangeness number of hadrons.
ELECTROMAGNETIC CONSTRUCTION OF A 1 KM-RADIUS RADIATION SHIELD
in the light of recent studies on bootstrapped lunar solar-electric power plants, mass drivers, and autonomous-drivers, (g) teleoperation of lunar and orbital facilities, (h) orbital assembly of lunar-derived solar power presence beyond Earth is limited to a very few government employees and robots who are sent up, entirely
Electromagnetic Wavelets as Hertzian Pulsed Beams in Complex Spacetime
Gerald Kaiser
2002-09-12T23:59:59.000Z
Electromagnetic wavelets are a family of 3x3 matrix fields W_z(x') parameterized by complex spacetime points z=x+iy with y timelike. They are translates of a \\sl basic \\rm wavelet W(z) holomorphic in the future-oriented union T of the forward and backward tubes. Applied to a complex polarization vector p (representing electric and magnetic dipole moments), W(z) gives an anti-selfdual solution W(z)p of Maxwell's equations derived from a selfdual Hertz potential Z(z)=-iS(z)p, where S is the \\sl Synge function \\rm acting as a Whittaker-like scalar Hertz potential. Resolutions of unity exist giving representations of sourceless electromagnetic fields as superpositions of wavelets. With the choice of a branch cut, S(z) splits into a difference of retarded and advanced \\sl pulsed beams \\rm whose limits as y\\to 0 give the propagators of the wave equation. This yields a similar splitting of the wavelets and leads to their complete physical interpretation as EM pulsed beams absorbed and emitted by a \\sl disk source \\rm D(y) representing the branch cut. The choice of y determines the beam's orientation, collimation and duration, giving beams as sharp and pulses as short as desired. The sources are computed as spacetime distributions of electric and magnetic dipoles supported on D(y). The wavelet representation of sourceless electromagnetic fields now splits into representations with advanced and retarded sources. These representations are the electromagnetic counterpart of relativistic coherent-state representations previously derived for massive Klein-Gordon and Dirac particles.
Electromagnetic Effects in SDF Explosions
Reichenbach, H; Neuwald, P; Kuhl, A L
2010-02-12T23:59:59.000Z
The notion of high ion and electron concentrations in the detonation of aluminized explosive mixtures has aroused some interest in electro-magnetic effects that the SDF charges might generate when detonated. Motivated by this interest we have started to investigate whether significant electro-magnetic effects show up in our small-scale experiments. However, the design of instrumentation for this purpose is far from straightforward, since there are a number of open questions. Thus the main aim of the feasibility tests is to find - if possible - a simple and reliable method that can be used as a diagnostic tool for electro-magnetic effects. SDF charges with a 0.5-g PETN booster and a filling of 1 g aluminum flakes have been investigated in three barometric bomb calorimeters with volumes ranging from 6.3 l to of 6.6 l. Though similar in volume, the barometric bombs differed in the length-to-diameter ratio. The tests were carried out with the bombs filled with either air or nitrogen at ambient pressure. The comparison of the test in air to those in nitrogen shows that the combustion of TNT detonation products or aluminum generates a substantial increase of the quasi-steady overpressure in the bombs. Repeated tests in the same configuration resulted in some scatter of the experimental results. The most likely reason is that the aluminum combustion in most or all cases is incomplete and that the amount of aluminum actually burned varies from test to test. The mass fraction burned apparently decreases with increasing aspect ratio L/D. Thus an L/D-ratio of about 1 is optimal for the performance of shock-dispersed-fuel combustion. However, at an L/D-ratio of about 5 the combustion still yields appreciable overpressure in excess of the detonation. For a multi-burst scenario in a tunnel environment with a number of SDF charges distributed along a tunnel section a spacing of 5 tunnel diameter and a fuel-specific volume of around 7 l/g might provide an acceptable compromise between optimizing the combustion performance and keeping the number of elementary charges low. Further tests in a barometric bomb calorimeter of 21.2 l volume were performed with four types of aluminum. The mass fraction burned in this case appeared to depend on the morphology of the aluminum particles. Flake aluminum exhibited a better performance than granulated aluminum with particle sizes ranging from below 25 {micro}m to 125 {micro}m for the coarsest material. In addition, a feasibility study on electro-magnetic effects from SDF charges detonated in a tunnel has been performed. A method was developed to measure the local, unsteady electro-conductivity in the detonation/combustion products cloud. This method proved to yield reproducible results. A variety of methods were tested with regard to probing electro-magnetic pulses from the detonation of SDF charges. The results showed little reproducibility and were small compared to the effect from pulsed high voltage discharges of comparatively small energy (around 32 J). Thus either no significant electromagnetic pulse is generated in our small-scale tests or the tested techniques have to be discarded as too insensitive or too limited in bandwidth to detect possibly very high frequency electro-magnetic disturbances.
Method of lightening radiation darkened optical elements
Reich, Frederich R. (Richland, WA); Schwankoff, Albert R. (W. Richland, WA)
1980-01-01T23:59:59.000Z
A method of lightening a radiation-darkened optical element in wich visible optical energy or electromagnetic radiation having a wavelength in the range of from about 2000 to about 20,000 angstroms is directed into the radiation-darkened optical element; the method may be used to lighten radiation-darkened optical element in-situ during the use of the optical element to transmit data by electronically separating the optical energy from the optical output by frequency filtering, data cooling, or interlacing the optic energy between data intervals.
Enhanced ULF electromagnetic activity detected by DEMETER above seismogenic regions
Athanasiou, M; David, C; Anagnostopoulos, G
2013-01-01T23:59:59.000Z
In this paper we present results of a comparison between ultra low frequency (ULF) electromagnetic (EM) radiation, recorded by an electric field instrument (ICE) onboard the satellite DEMETER in the topside ionosphere, and the seismicity of regions with high and lower seiismic activity. In particular we evaluated the energy variations of the ULF Ez-electric field component during a period of four years (2006-2009), in order to examine check the possible relation of ULF EM radiation with seismogenic regions located in central America, Indonesia, Eastern Mediterranean Basin and Greece. As a tool of evaluating the ULF Ez energy variations we used Singular Spectrum Analysis (SSA) techniques. The results of our analysis clearly show a significant increase of the ULF EM energy emmited from regions of highest seismic activity at the tectonic plates boundaries. We interpret these results as suggesting that the highest ULF EM energy detected in the topside ionosphere is originated from seismic processes within Earth's...
Radiation: Radiation Control (Indiana)
Broader source: Energy.gov [DOE]
It is the policy of the state to encourage the constructive uses of radiation and to control its harmful effects. This section contains regulations pertaining to the manufacture, use,...
Entanglement from thermal black body radiation
Daniel Braun
2005-09-06T23:59:59.000Z
Two non--interacting quantum systems which couple to a common environment with many degrees of freedom initially in thermal equilibrium can become entangled due to the indirect interaction mediated through this heat bath. I examine here the dynamics of reservoir induced entanglement for a heat bath consisting of a thermal electro--magnetic radiation field, such as black body radiation or the cosmic microwave background, and show how the effect can be understood as result of an effective induced interaction.
On the Energy of Rotating Gravitational Waves
Bahram Mashhoon; James C. McClune; Enrique Chavez; Hernando Quevedo
1996-09-06T23:59:59.000Z
A class of solutions of the gravitational field equations describing vacuum spacetimes outside rotating cylindrical sources is presented. A subclass of these solutions corresponds to the exterior gravitational fields of rotating cylindrical systems that emit gravitational radiation. The properties of these rotating gravitational wave spacetimes are investigated. In particular, we discuss the energy density of these waves using the gravitational stress-energy tensor.
Elgen Wave | Open Energy Information
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualPropertyd8c-a9ae-f8521cbb8489 No revision| OpenElectromagnetic ProfilingElgen Wave Jump to:
A study of electromagnetic fields in horn antennas containing two eielectrics
Quddus, Mohammad Abdul
1960-01-01T23:59:59.000Z
A STUDY OF ELECTROMAGNETIC FIELDS IN HORN ANTENNAS CONTAINING TWO DIELECTRICS A Thesis by MD. ABDUL QUDDUS Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements... dielectric has been made by Barrow and Chu. The design of optimum air- 2 filled horn has been studied by Barrow and Chu and by Braun. Barton 3 13 11 and Rhodes4 have worked on the radiation pattern, and the gain of the electromagnetic horns has been...
Quasi light fields: extending the light field to coherent radiation
Wornell, Gregory W.
Quasi light fields: extending the light field to coherent radiation Anthony Accardi1,2 and Gregory light field, and for coherent radiation using electromagnetic field theory. We present a model of coherent image formation that strikes a balance between the utility of the light field
Y-12 electromagnetic separation process wins approval
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
work immediately. Just like what we know of Groves, huh. The gaseous diffusion, reactor pile and electromagnetic separation approaches were reviewed with each group attempting to...
Electromagnetic compatibility of nuclear power plants
Cabayan, H.S.
1983-01-01T23:59:59.000Z
Lately, there has been a mounting concern about the electromagnetic compatibility of nuclear-power-plant systems mainly because of the effects due to the nuclear electromagnetic pulse, and also because of the introduction of more-sophisticated and, therefore, more-susceptible solid-state devices into the plants. Questions have been raised about the adequacy of solid-state-device protection against plant electromagnetic-interference sources and transients due to the nuclear electromagnetic pulse. In this paper, the author briefly reviews the environment, and the coupling, susceptibility, and vulnerability assessment issues of commercial nuclear power plants.
Airborne electromagnetic surveys as a reconnaissance technique...
geothermal exploration Jump to: navigation, search OpenEI Reference LibraryAdd to library Conference Proceedings: Airborne electromagnetic surveys as a reconnaissance technique for...
6.630 Electromagnetic Theory, Fall 2002
Kong, Jin Au, 1942-
6.630 is an introductory subject on electromagnetics, emphasizing fundamental concepts and applications of Maxwell equations. Topics covered include: polarization, dipole antennas, wireless communications, forces and energy, ...
Quantum modulation against electromagnetic interference
Juan Carlos Garcia-Escartin
2014-11-26T23:59:59.000Z
Periodic signals in electrical and electronic equipment can cause interference in nearby devices. Randomized modulation of those signals spreads their energy through the frequency spectrum and can help to mitigate electromagnetic interference problems. The inherently random nature of quantum phenomena makes them a good control signal. I present a quantum modulation method based on the random statistics of quantum light. The paper describes pulse width modulation schemes where a Poissonian light source acts as a random control that spreads the energy of the potential interfering signals. I give an example application for switching-mode power supplies and comment the further possibilities of the method.
Electromagnetic properties of massive neutrinos
Dobrynina, A. A., E-mail: aleksandradobrynina@rambler.ru; Mikheev, N. V.; Narynskaya, E. N. [Demidov Yaroslavl State University (Russian Federation)] [Demidov Yaroslavl State University (Russian Federation)
2013-10-15T23:59:59.000Z
The vertex function for a virtual massive neutrino is calculated in the limit of soft real photons. A method based on employing the neutrino self-energy operator in a weak external electromagnetic field in the approximation linear in the field is developed in order to render this calculation of the vertex function convenient. It is shown that the electric charge and the electric dipole moment of the real neutrino are zero; only the magnetic moment is nonzero for massive neutrinos. A fourth-generation heavy neutrino of mass not less than half of the Z-boson mass is considered as a massive neutrino.
Why does gravitational radiation produce vorticity?
L. Herrera; W. Barreto; J. Carot; A. Di Prisco
2007-03-26T23:59:59.000Z
We calculate the vorticity of world--lines of observers at rest in a Bondi--Sachs frame, produced by gravitational radiation, in a general Sachs metric. We claim that such an effect is related to the super--Poynting vector, in a similar way as the existence of the electromagnetic Poynting vector is related to the vorticity in stationary electrovacum spacetimes.
Liu Yueqiang; Connor, J. W.; Cowley, S. C.; Ham, C. J.; Hastie, R. J.; Hender, T. C. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)
2012-10-15T23:59:59.000Z
A numerical study is carried out, based on a simple toroidal tokamak equilibrium, to demonstrate the radial re-distribution of the electromagnetic torque density, as a result of a rotating resistive plasma (linear) response to a static resonant magnetic perturbation field. The computed electromagnetic torque peaks at several radial locations even in the presence of a single rational surface, due to resonances between the rotating response, in the plasma frame, and both Alfven and sound continuum waves. These peaks tend to merge together to form a rather global torque distribution, when the plasma resistivity is large. The continuum resonance induced net electromagnetic torque remains finite even in the limit of an ideal plasma.
Coherent Radio Pulses From GEANT Generated Electromagnetic Showers In Ice
Soebur Razzaque; Surujhdeo Seunarine; David Z. Besson; Douglas W. McKay; John P. Ralston; David Seckel
2002-02-25T23:59:59.000Z
Radio Cherenkov radiation is arguably the most efficient mechanism for detecting showers from ultra-high energy particles of 1 PeV and above. Showers occuring in Antarctic ice should be detectable at distances up to 1 km. We report on electromagnetic shower development in ice using a GEANT Monte Carlo simulation. We have studied energy deposition by shower particles and determined shower parameters for several different media, finding agreement with published results where available. We also report on radio pulse emission from the charged particles in the shower, focusing on coherent emission at the Cherenkov angle. Previous work has focused on frequencies in the 100 MHz to 1 GHz range. Surprisingly, we find that the coherence regime extends up to tens of Ghz. This may have substantial impact on future radio-based neutrino detection experiments as well as any test beam experiment which seeks to measure coherent Cherenkov radiation from an electromagnetic shower. Our study is particularly important for the RICE experiment at the South Pole.
Melamed, Timor
Progress In Electromagnetics Research, Vol. 114, 317332, 2011 PULSED BEAM EXPANSION-based pulsed-beams expansion of planar aperture time- dependent electromagnetic fields. The propagating field-beam waveobjects over the frame spectral lattice. Explicit asymptotic expressions for the electromagnetic pulsed
JournalofGeophysicalResearch: Atmospheres RESEARCH ARTICLE
to optical frequencies, extending to X-rays and gamma rays. The electromagnetic pulse associated to its abundance in nature. Lightning processes radiate impulsive electromagnetic waves from DC
Wireless passive radiation sensor
Pfeifer, Kent B; Rumpf, Arthur N; Yelton, William G; Limmer, Steven J
2013-12-03T23:59:59.000Z
A novel measurement technique is employed using surface acoustic wave (SAW) devices, passive RF, and radiation-sensitive films to provide a wireless passive radiation sensor that requires no batteries, outside wiring, or regular maintenance. The sensor is small (<1 cm.sup.2), physically robust, and will operate unattended for decades. In addition, the sensor can be insensitive to measurement position and read distance due to a novel self-referencing technique eliminating the need to measure absolute responses that are dependent on RF transmitter location and power.
Paul S. Wesson
2012-12-11T23:59:59.000Z
As an example of the unification of gravitation and particle physics, an exact solution of the five-dimensional field equations is studied which describes waves in the classical Einstein vacuum. While the solution is essentially 5D in nature, the waves exist in ordinary 3D space, and may provide a way to test for an extra dimension.
The effects of lightning and high altitude electromagnetic pulse on power distribution lines
Uman, M.A.; Rubinstein, M.; Yacoub, Z. [Florida Univ., Gainesville, FL (United States)
1995-01-01T23:59:59.000Z
We simultaneously recorded the voltages induced by lightning on both ends of an unenergized 448-meter long unenergized electric power line and the lightning vertical electric and horizontal magnetic fields at ground level near the line. The lightning data studied and presented here were due both to cloud lightning and to very close (about 20 m from the line) artificially initiated lightning. For cloud sources, a frequency-domain computer program called EMPLIN was used to calculate induced line voltages as a function of source elevation, angle of incidence, and wave polarization of the radiated cloud discharge pulses in order to compare with the measurements. For very-close lightning, the measured line voltages could be grouped into two categories, those in which multiple, similarly shaped, evenly spaced pulses were observed, which we call oscillatory, and those dominated by a principal pulse with subsidiary oscillations of much smaller amplitude, which we call impulsive. The amplitude of the induced voltage ranged from tens of kilovolts for oscillatory voltages to hundreds of kilovolts for impulsive voltages. A new technique is derived for the calculation of the electromagnetic fields from nearby lightning to ground above an imperfectly conducting ground. This technique was used in conjunction with an existing time domain coupling theory and lightning return stroke model to calculate voltages at either end of the line. The results show fair agreement with the measured oscillatory voltage waveforms if corona is ignored and improved results when corona effects are modeled. The modeling of the impulsive voltage, for which local flashover probably successful. In an attempt to understand better the sources of the line voltages for very close lightning, measurements of the horizontal and vertical electric fields 30 m from triggered lightning were obtained.
Electromagnetically Restrained Lithium Blanket APEX Interim Report November, 1999
California at Los Angeles, University of
to avoid corrosion or fire. Lithium's high electrical conductivity may possibly permit efficient, compactElectromagnetically Restrained Lithium Blanket APEX Interim Report November, 1999 6-1 CHAPTER 6: ELECTROMAGNETICALLY RESTRAINED LITHIUM BLANKET Contributors Robert Woolley #12;Electromagnetically Restrained Lithium
Excitation of terahertz nanoantennas by Rabi waves
Slepyan, G. Ya.; Yerchak, Y. D.; Maksimenko, S. A. [Institute for Nuclear Problems, Belarus State University, Bobruiskaya 11, 220030 Minsk (Belarus); Hoffmann, A. [Institut fuer Festkoerperphysik, Technische Universitaet Berlin, Hardenbergstrasse 36, 10623 Berlin (Germany); Bass, F. G. [Department of Physics, Bar-Ilan University, 52900 Ramat-Gan (Israel)
2011-10-03T23:59:59.000Z
Theoretical model of quantum dot ring, strongly coupled with classical electromagnetic field, is developed. We demonstrate, that tunnel current in the QD-ring has low-frequency component, excited by Rabi waves, propagating into the ring, and the ring can be considered as a candidate for role of terahertz magnetic loop antenna. The low-frequency current is inspired by the asymmetry of electron tunneling.
Narrow field electromagnetic sensor system and method
McEwan, Thomas E. (Livermore, CA)
1996-01-01T23:59:59.000Z
A narrow field electromagnetic sensor system and method of sensing a characteristic of an object provide the capability to realize a characteristic of an object such as density, thickness, or presence, for any desired coordinate position on the object. One application is imaging. The sensor can also be used as an obstruction detector or an electronic trip wire with a narrow field without the disadvantages of impaired performance when exposed to dirt, snow, rain, or sunlight. The sensor employs a transmitter for transmitting a sequence of electromagnetic signals in response to a transmit timing signal, a receiver for sampling only the initial direct RF path of the electromagnetic signal while excluding all other electromagnetic signals in response to a receive timing signal, and a signal processor for processing the sampled direct RF path electromagnetic signal and providing an indication of the characteristic of an object. Usually, the electromagnetic signal is a short RF burst and the obstruction must provide a substantially complete eclipse of the direct RF path. By employing time-of-flight techniques, a timing circuit controls the receiver to sample only the initial direct RF path of the electromagnetic signal while not sampling indirect path electromagnetic signals. The sensor system also incorporates circuitry for ultra-wideband spread spectrum operation that reduces interference to and from other RF services while allowing co-location of multiple electronic sensors without the need for frequency assignments.
Ultimate Energy Densities for Electromagnetic Pulses
Mankei Tsang
2008-03-06T23:59:59.000Z
The ultimate electric and magnetic energy densities that can be attained by bandlimited electromagnetic pulses in free space are calculated using an ab initio quantized treatment, and the quantum states of electromagnetic fields that achieve the ultimate energy densities are derived. The ultimate energy densities also provide an experimentally accessible metric for the degree of localization of polychromatic photons.
Narrow field electromagnetic sensor system and method
McEwan, T.E.
1996-11-19T23:59:59.000Z
A narrow field electromagnetic sensor system and method of sensing a characteristic of an object provide the capability to realize a characteristic of an object such as density, thickness, or presence, for any desired coordinate position on the object. One application is imaging. The sensor can also be used as an obstruction detector or an electronic trip wire with a narrow field without the disadvantages of impaired performance when exposed to dirt, snow, rain, or sunlight. The sensor employs a transmitter for transmitting a sequence of electromagnetic signals in response to a transmit timing signal, a receiver for sampling only the initial direct RF path of the electromagnetic signal while excluding all other electromagnetic signals in response to a receive timing signal, and a signal processor for processing the sampled direct RF path electromagnetic signal and providing an indication of the characteristic of an object. Usually, the electromagnetic signal is a short RF burst and the obstruction must provide a substantially complete eclipse of the direct RF path. By employing time-of-flight techniques, a timing circuit controls the receiver to sample only the initial direct RF path of the electromagnetic signal while not sampling indirect path electromagnetic signals. The sensor system also incorporates circuitry for ultra-wideband spread spectrum operation that reduces interference to and from other RF services while allowing co-location of multiple electronic sensors without the need for frequency assignments. 12 figs.
Optimization Material Distribution methodology: Some electromagnetic examples
Paris-Sud XI, UniversitÃ© de
730 1 Optimization Material Distribution methodology: Some electromagnetic examples P. Boissoles, H. Ben Ahmed, M. Pierre, B. Multon Abstract--In this paper, a new approach towards Optimization Material to be highly adaptive to various kinds of electromagnetic actuator optimization approaches. Several optimal
Radiation of a neutral polarizable particle moving uniformly through a thermal radiation field
G. V. Dedkov; A. A. Kyasov
2014-06-25T23:59:59.000Z
We discuss the properties of thermal electromagnetic radiation produced by a neutral polarizable nanoparticle moving with an arbitrary relativistic velocity in a heated vacuum background with a fixed temperature. We show that the particle in its own rest frame acquires the radiation temperature of vacuum, multiplied by a velocity-dependent factor, and then emits thermal photons predominantly in the forward direction. The intensity of radiation proves to be much higher than for the particle at rest. For metal particles with high energy, the ratio of emitted and absorbed radiation power is proportional to the Lorentz-factor squared.
Photon wave functions, wave-packet quantization of light, and coherence theory
Brian J. Smith; M. G. Raymer
2007-12-09T23:59:59.000Z
The monochromatic Dirac and polychromatic Titulaer-Glauber quantized field theories (QFTs) of electromagnetism are derived from a photon-energy wave function in much the same way that one derives QFT for electrons, that is, by quantization of a single-particle wave function. The photon wave function and its equation of motion are established from the Einstein energy-momentum-mass relation, assuming a local energy density. This yields a theory of photon wave mechanics (PWM). The proper Lorentz-invariant single-photon scalar product is found to be non-local in coordinate space, and is shown to correspond to orthogonalization of the Titulaer-Glauber wave-packet modes. The wave functions of PWM and mode functions of QFT are shown to be equivalent, evolving via identical equations of motion, and completely describe photonic states. We generalize PWM to two or more photons, and show how to switch between the PWM and QFT viewpoints. The second-order coherence tensors of classical coherence theory and the two-photon wave functions are shown to propagate equivalently. We give examples of beam-like states, which can be used as photon wave functions in PWM, or modes in QFT. We propose a practical mode converter based on spectral filtering to convert between wave packets and their corresponding biorthogonal dual wave packets.
Noninvasive valve monitor using alternating electromagnetic field
Eissenberg, David M. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN); Casada, Donald A. (Knoxville, TN)
1993-01-01T23:59:59.000Z
One or more electrical coils are carefully located on the outside of a valve body. An alternating current passing through the coil(s) results in an alternating electromagnetic field being transmitted into the valve body and valve internals. The electromagnetic field varies in intensity and polarity in the valve. As the position of a valve internal part is changed, the electromagnetic field throughout the valve body and its internals is altered. A passive receiver coil carefully located on the outside of the valve body detects the intensity of the electromagnetic field at that location as an induced electrical voltage in the coil. With the change in position of the valve internal part, there is a corresponding change in the induced voltage as a result of the alteration in the alternating electromagnetic field at that location. Changes in the voltage provide an indication of the position and motion of valve internals.
Nonlinear extraordinary wave in dense plasma
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)
2013-10-15T23:59:59.000Z
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.
Hugonin, Jean-Paul; Ben-Abdallah, Philippe
2015-01-01T23:59:59.000Z
Absorption and scattering of electromagnetic waves by dielectric media are of fundamental importance in many branches of physics. In this Letter we analytically derived the ultimate upper limits for the absorbed and scattered powers by any system of optical resonators in mutual interaction. We show that these bounds depend only on the geometric configuration given an incident field. We give the conditions to fullfill to reach these limits paving so a way for a rational design of optimal metamaterials.
The Nature of Running Penumbral Waves Revealed
D. Shaun Bloomfield; Andreas Lagg; Sami K. Solanki
2007-09-24T23:59:59.000Z
We seek to clarify the nature of running penumbral (RP) waves: are they chromospheric trans-sunspot waves or a visual pattern of upward-propagating waves? Full Stokes spectropolarimetric time series of the photospheric Si I 10827 \\AA line and the chromospheric He I 10830 \\AA multiplet were inverted using a Milne-Eddington atmosphere. Spatial pixels were paired between the outer umbral/inner penumbral photosphere and the penumbral chromosphere using inclinations retrieved by the inversion and the dual-height pairings of line-of-sight velocity time series were studied for signatures of wave propagation using a Fourier phase difference analysis. The dispersion relation for radiatively cooling acoustic waves, modified to incorporate an inclined propagation direction, fits well the observed phase differences between the pairs of photospheric and chromospheric pixels. We have thus demonstrated that RP waves are in effect low-beta slow-mode waves propagating along the magnetic field.
Controlled Source Frequency-Domain Electromagnetics At Neal Hot...
Source Frequency-Domain Electromagnetics Activity Date 2011 - 2011 Usefulness useful DOE-funding Unknown Exploration Basis Electromagnetic surveys were conducted to gain a better...
applied computational electromagnetics: Topics by E-print Network
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Electromagnetics Geosciences Websites Summary: Max Optics, Inc. 12;MadMax Optics 2 Stealth Electromagnetic interference Antennas on complex platformsFMM Code...
Latyshev, A V
2015-01-01T23:59:59.000Z
From Vlasov kinetic equation for collisionless plasmas distribution function in square-law approximation on size of electromagnetic field is received. Formulas for calculation electric current at any temperature (any degree of degeneration of electronic gas) are deduced. The case of small values of the wave numbers is considered. It is shown, that the nonlinearity account leads to occurrence the longitudinal electric current directed along a wave vector. This longitudinal current orthogonal to known transversal classical current, received at the linear analysis. From the kinetic equation with Wigner integral for collisionless quantum plasma distribution function is received in square-law on vector potential approximation. Formulas for calculation electric current at any temperature are deduced. The case of small values of wave number is considered. It is shown, that size of a longitudinal current at small values of wave number and for classical plasma and for quantum plasma coincide. Graphic comparison of dim...
K. -I. Nishikawa; P. Hardee; G. Richardson; R. Preece; H. Sol; G. J. Fishman
2003-12-03T23:59:59.000Z
Shock acceleration is an ubiquitous phenomenon in astrophysical plasmas. Plasma waves and their associated instabilities (e.g., the Buneman instability, two-streaming instability, and the Weibel instability) created in the shocks are responsible for particle (electron, positron, and ion) acceleration. Using a 3-D relativistic electromagnetic particle (REMP) code, we have investigated particle acceleration associated with a relativistic jet front propagating through an ambient plasma with and without initial magnetic fields. We find only small differences in the results between no ambient and weak ambient magnetic fields. Simulations show that the Weibel instability created in the collisionless shock front accelerates particles perpendicular and parallel to the jet propagation direction. The simulation results show that this instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields, which contribute to the electron's transverse deflection behind the jet head. The ``jitter'' radiation from deflected electrons has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation may be important to understanding the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.
Moncada-Villa, Edwin; Garcia-Vidal, Francisco J; Garcia-Martin, Antonio; Cuevas, Juan Carlos
2015-01-01T23:59:59.000Z
We present a comprehensive theoretical study of the magnetic field dependence of the near-field radiative heat transfer (NFRHT) between two parallel plates. We show that when the plates are made of doped semiconductors, the near-field thermal radiation can be severely affected by the application of a static magnetic field. We find that irrespective of its direction, the presence of a magnetic field reduces the radiative heat conductance, and dramatic reductions up to 700% can be found with fields of about 6 T at room temperature. We show that this striking behavior is due to the fact that the magnetic field radically changes the nature of the NFRHT. The field not only affects the electromagnetic surface waves (both plasmons and phonon polaritons) that normally dominate the near-field radiation in doped semiconductors, but it also induces hyperbolic modes that progressively dominate the heat transfer as the field increases. In particular, we show that when the field is perpendicular to the plates, the semicond...
Excitation of Banded Whistler Waves in the Magnetosphere
Gary, S. Peter [Los Alamos National Laboratory; Liu, Kaijun [Los Alamos National Laboratory; Winske, Dan [Los Alamos National Laboratory
2012-07-13T23:59:59.000Z
Banded whistler waves can be generated by the whistler anisotropy instability driven by two bi-Maxwellian electron components with T{sub {perpendicular}}/T{sub {parallel}} > 1 at different T{sub {parallel}} For typical magnetospheric condition of 1 < {omega}{sub e}/{Omega}{sub e} < 5 in regions associated with strong chorus, upper-band waves can be excited by anisotropic electrons below {approx} 1 keV, while lower-band waves are excited by anisotropic electrons above {approx} 10 keV. Lower-band waves are generally field-aligned and substantially electromagnetic, while upper-band waves propagate obliquely and have quasi-electrostatic fluctuating electric fields. The quasi-electrostatic feature of upper-band waves suggests that they may be more easily identified in electric field observations than in magnetic field observations. Upper-band waves are liable to Landau damping and the saturation level of upperband waves is lower than lower-band waves, consistent with observations that lower-band waves are stronger than upper-band waves on average. The oblique propagation, the lower saturation level, and the more severe Landau damping together would make upper-band waves more tightly confined to the geomagnetic equator (|{lambda}{sub m}| < {approx}10{sup o}) than lower-band waves.
Efficient weakly-radiative wireless energy transfer: An EIT-like approach
Hamam, Rafif E.
Inspired by a quantum interference phenomenon known in the atomic physics community as electromagnetically induced transparency (EIT), we propose an efficient weakly radiative wireless energy transfer scheme between two ...
M. Atiqur Rahman; M. Hossain Ali
2009-02-22T23:59:59.000Z
The transverse electromagnetic waves propagating in a relativistic two-fluid plasma influenced by the gravitational field of the Reissner-Nordstr\\"{o}m-de Sitter black hole has been investigated exploiting 3+1 split of spacetime. Reformulating the two-fluid equations, the set of simultaneous linear equations for the perturbations have been derived. Using a local approximation, the one-dimensional radial propagation of Alfv\\'{e}n and high frequency electromagnetic waves are investigated. The dispersion relation for these waves is obtained and solved numerically for the wave number.
Wave packet dynamics of the matter wave field of a Bose-Einstein condensate
C. Sudheesh; S. Lakshmibala; V. Balakrishnan
2004-08-11T23:59:59.000Z
We show in the framework of a tractable model that revivals and fractional revivals of wave packets afford clear signatures of the extent of departure from coherence and from Poisson statistics of the matter wave field in a Bose-Einstein condensate, or of a suitably chosen initial state of the radiation field propagating in a Kerr-like medium.
Survey of ambient electromagnetic and radio-frequency interference levels in nuclear power plants
Kercel, S.W.; Moore, M.R.; Blakeman, E.D.; Ewing, P.D.; Wood, R.T.
1996-11-01T23:59:59.000Z
This document reports the results of a survey of ambient electromagnetic conditions in representative nuclear power plants. The U.S. Nuclear Regulatory Commission (NRC) Office of Nuclear Regulatory Research engaged the Oak Ridge National Laboratory (ORNL) to perform these measurements to characterize the electromagnetic interference (EMI) and radio-frequency interference (RFI) levels that can be expected in nuclear power plant environments. This survey is the first of its kind, being based on long-term unattended observations. The data presented in this report were measured at eight different nuclear units and required 14 months to collect. A representative sampling of power plant conditions (reactor type, operating mode, site location) monitored over extended observation periods (up to 5 weeks) were selected to more completely determine the characteristic electromagnetic environment for nuclear power plants. Radiated electric fields were measured over the frequency range of 5 MHz to 8 GHz. Radiated magnetic fields and conducted EMI events were measured over the frequency range of 305 Hz to 5 MHz. Highest strength observations of the electromagnetic ambient environment across all measurement conditions at each site provide frequency-dependent profiles for EMI/RFI levels in nuclear power plants.
Numerical Methods of Computational Electromagnetics for Complex Inhomogeneous Systems
Cai, Wei
2014-05-15T23:59:59.000Z
Understanding electromagnetic phenomena is the key in many scientific investigation and engineering designs such as solar cell designs, studying biological ion channels for diseases, and creating clean fusion energies, among other things. The objectives of the project are to develop high order numerical methods to simulate evanescent electromagnetic waves occurring in plasmon solar cells and biological ion-channels, where local field enhancement within random media in the former and long range electrostatic interactions in the latter are of major challenges for accurate and efficient numerical computations. We have accomplished these objectives by developing high order numerical methods for solving Maxwell equations such as high order finite element basis for discontinuous Galerkin methods, well-conditioned Nedelec edge element method, divergence free finite element basis for MHD, and fast integral equation methods for layered media. These methods can be used to model the complex local field enhancement in plasmon solar cells. On the other hand, to treat long range electrostatic interaction in ion channels, we have developed image charge based method for a hybrid model in combining atomistic electrostatics and continuum Poisson-Boltzmann electrostatics. Such a hybrid model will speed up the molecular dynamics simulation of transport in biological ion-channels.
Determination of electromagnetic medium from the Fresnel surface
Matias F. Dahl
2011-03-16T23:59:59.000Z
We study Maxwell's equations on a 4-manifold where the electromagnetic medium is described by an antisymmetric $2\\choose 2$-tensor $\\kappa$. In this setting, the Tamm-Rubilar tensor density determines a polynomial surface of fourth order in each cotangent space. This surface is called the Fresnel surface and acts as a generalisation of the light-cone determined by a Lorentz metric; the Fresnel surface parameterises electromagnetic wave-speed as a function of direction. Favaro and Bergamin have recently proven that if $\\kappa$ has only a principal part and if the Fresnel surface of $\\kappa$ coincides with the light cone for a Lorentz metric $g$, then $\\kappa$ is proportional to the Hodge star operator of $g$. That is, under additional assumptions, the Fresnel surface of $\\kappa$ determines the conformal class of $\\kappa$. The purpose of this paper is twofold. First, we provide a new proof of this result using Gr\\"obner bases. Second, we describe a number of cases where the Fresnel surface does not determine the conformal class of the original $2\\choose 2$-tensor $\\kappa$. For example, if $\\kappa$ is invertible we show that $\\kappa$ and $\\kappa^{-1}$ have the same Fresnel surfaces.
High frequency electromagnetic burn monitoring for underground coal gasification
Deadrick, F.J.; Hill, R.W.; Laine, E.F.
1981-06-17T23:59:59.000Z
This paper describes the use of high frequency electromagnetic waves to monitor an in-situ coal gasification burn process, and presents some recent results obtained with the method. Both the technique, called HFEM (high frequency electromagnetic) probing, the HFEM hardware used are described, and some of the data obtained from the LLNL Hoe Creek No. 3 underground coal gasification experiment conducted near Gillette, Wyoming are presented. HFEM was found to be very useful for monitoring the burn activity found in underground coal gasification. The technique, being a remote sensing method which does not require direct physical contact, does not suffer from burnout problems as found with thermocouples, and can continue to function even as the burn progresses on through the region of interest. While HFEM does not replace more conventional instrumentation such as thermocouples, the method does serve to provide data which is unobtainable by other means, and in so doing it complements the other data to help form a picture of what cannot be seen underground.
ATS 351, Spring 2010 Energy & Radiation 60 points
Rutledge, Steven
energy per wave? Why? Shorter wavelengths carry more energy per wave. Therefore, the sun's radiationATS 351, Spring 2010 Lab #2 Energy & Radiation 60 points Please show your work for calculations Question #1: Energy (11 points) Heat is a measure of the transfer of energy from a body with a higher
Cosmic Electromagnetic Fields due to Perturbations in the Gravitational Field
Bishop Mongwane; Peter K. S. Dunsby; Bob Osano
2012-10-21T23:59:59.000Z
We use non-linear gauge-invariant perturbation theory to study the interaction of an inflation produced seed magnetic field with density and gravitational wave perturbations in an almost Friedmann-Lema\\^itre-Robertson-Walker (FLRW) spacetime. We compare the effects of this coupling under the assumptions of poor conductivity, infinite conductivity and the case where the electric field is sourced via the coupling of velocity perturbations to the seed field in the ideal magnetohydrodynamic (MHD) regime, thus generalizing, improving on and correcting previous results. We solve our equations for long wavelength limits and numerically integrate the resulting equations to generate power spectra for the electromagnetic field variables, showing where the modes cross the horizon. We find that the rotation of the electric field dominates the power spectrum on small scales, in agreement with previous arguments.
Variational Principles for Constrained Electromagnetic Field and Papapetrou Equation
A. T. Muminov
2007-06-28T23:59:59.000Z
In our previous article [4] an approach to derive Papapetrou equations for constrained electromagnetic field was demonstrated by use of field variational principles. The aim of current work is to present more universal technique of deduction of the equations which could be applied to another types of non-scalar fields. It is based on Noether theorem formulated in terms of Cartan' formalism of orthonormal frames. Under infinitesimal coordinate transformation the one leads to equation which includes volume force of spin-gravitational interaction. Papapetrou equation for vector of propagation of the wave is derived on base of the equation. Such manner of deduction allows to formulate more accurately the constraints and clarify equations for the potential and for spin.
Wave represents displacement Wave represents pressure Source -Sound Waves
Colorado at Boulder, University of
Wave represents displacement Wave represents pressure Source - Sound Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency Wave represents pressure Target - Radio Waves Distance between crests is wavelength Number of crests passing a point in 1 second is frequency
Linked and Knotted Gravitational Radiation
Amy Thompson; Joe Swearngin; Dirk Bouwmeester
2014-08-15T23:59:59.000Z
We show that the torus knot topology is inherent in electromagnetic and gravitational radiation by constructing spin-$N$ fields based on this topology from the elementary states of twistor theory. The twistor functions corresponding to the elementary states admit a parameterization in terms of the poloidal and toroidal winding numbers of the torus knots, allowing one to choose the degree of linking or knotting of the associated field configuration. Using the gravito-electromagnetic formalism, we show that the torus knot structure is exhibited in the tendex and vortex lines for the analogous linearized gravitational solutions. We describe the topology of the gravitational fields and its physical interpretation in terms of the tidal and frame drag forces of the gravitational field.
Shock Wave Polarizations and Optical Metrics in the Born and the Born-Infeld Electrodynamics
Christoph Minz; Horst-Heino von Borzeszkowski; Thoralf Chrobok; Gerold Schellstede
2015-02-27T23:59:59.000Z
We analyze the behavior of shock waves in nonlinear theories of electrodynamics. For this, by use of generalized Hadamard step functions of increasing order, the electromagnetic potential is developed in a series expansion near the shock wave front. This brings about a corresponding expansion of the respective electromagnetic field equations what allows for deriving relations that determine the jump coefficients in the expansion series of the potential. The solution of the first-order jump relations shows that, in contrast to linear Maxwell's electrodynamics, in general the propagation of shock waves in nonlinear theories is governed by optical metrics and polarization conditions describing the propagation of two differently polarized waves (leading to a possible appearance of birefringence). In detail, shock waves are analyzed in the Born and Born-Infeld theories. The obtained results are compared to those ones found in literature. New results for the polarization of the two different waves are derived.
Nanoplasmonics-enabled On-Demand and Systematic Gene Regulation
Lee, Eunice Somin
2010-01-01T23:59:59.000Z
electromagnetic radiation (electric field E, wave vector k)radiation, the antenna is subject to a uniform static electricelectric field when its size is much smaller than the wavelength of the incoming electromagnetic radiation,
On analytic solutions of wave equations in regular coordinate systems on Schwarzschild background
Philipp, Dennis
2015-01-01T23:59:59.000Z
The propagation of (massless) scalar, electromagnetic and gravitational waves on fixed Schwarzschild background spacetime is described by the general time-dependent Regge-Wheeler equation. We transform this wave equation to usual Schwarzschild, Eddington-Finkelstein, Painleve-Gullstrand and Kruskal-Szekeres coordinates. In the first three cases, but not in the last one, it is possible to separate a harmonic time-dependence. Then the resulting radial equations belong to the class of confluent Heun equations, i.e., we can identify one irregular and two regular singularities. Using the generalized Riemann scheme we collect properties of all the singular points and construct analytic (local) solutions in terms of the standard confluent Heun function HeunC, Frobenius and asymptotic Thome series. We study the Eddington-Finkelstein case in detail and obtain a solution that is regular at the black hole horizon. This solution satisfies causal boundary conditions, i.e., it describes purely ingoing radiation at $r=2M$. ...
T-wave generation and propagation: A comparison between data and spectral element modelinga)
Boyer, Edmond
T-wave generation and propagation: A comparison between data and spectral element modelinga August 2013) T-waves are underwater acoustic waves generated by earthquakes. Modeling of their generation realistic simulations of T-waves taking into account major aspects of this phenomenon: The radiation pattern
Dynamic programming applied to electromagnetic satellite actuation
Eslinger, Gregory John
2013-01-01T23:59:59.000Z
Electromagnetic formation flight (EMFF) is an enabling technology for a number of space mission architectures. While much work has been done for EMFF control for large separation distances, little work has been done for ...
Testing Loop Quantum Gravity and Electromagnetic Dark Energy in Superconductors
Clovis Jacinto de Matos
2009-08-06T23:59:59.000Z
In 1989 Cabrera and Tate reported an anomalous excess of mass of the Cooper pairs in rotating thin Niobium rings. So far, this experimental result never received a proper theoretical explanation in the context of superconductor's physics. In the present work we argue that what Cabrera and Tate interpreted as an anomalous excess of mass can also be associated with a deviation from the classical gravitomagnetic Larmor theorem due to the presence of dark energy in the superconductor, as well as with the discrete structure of the area of the superconducting Niobium ring as predicted by Loop Quantum Gravity. From Cabrera and Tate measurements we deduce that the quantization of spacetime in superconducting circular rings occurs at the Planck-Einstein scale $l_{PE} = (\\hbar G/c^3 \\Lambda)^{1/4}\\sim 3.77\\times 10 ^{-5} m$, instead of the Planck scale $l_{P} =(\\hbar G / c^3)^{1/2}=1.61 \\times 10 ^{-35} m$, with an Immirzi parameter which depends on the specific critical temperature of the superconducting material and on the area of the ring. The stephan-Boltzmann law for quantized areas delimited by superconducting rings is predicted, and an experimental concept based on the electromagnetic black-body radiation emitted by this surfaces, is proposed to test loop quantum gravity and electromagnetic dark energy in superconductors.
An interpretation of the black-body radiation
Shun-ichiro Koh
2002-08-02T23:59:59.000Z
The black-body radiation is reinterpreted in terms of the photon's many-body wave functions in analogy with the condensed matter physics. This interpretation has implications on the wave-particle duality, and on the difference between the photon and the matter wave.
Characterization of electromagnetic transients in power substations
Goers, William Chester
1980-01-01T23:59:59.000Z
CHARACTERIZATION OF ELECTROMAGNETIC TRANSIENTS IN POWER SUBSTATIONS A Thesis by WILLIAM CHESTER CiOERS, JR. Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of MASTER... OF SCIENCE December 1980 Major Subject: Electrical Engineering CHARACTERIZATION OF ELECTROMAGNETIC TRANSIENTS IN POWER SUBSTATIONS A Thesis by WILLIAM CHESTER GOERS, JR. Approved as to style and content by: Dr. B. Don Russell (Chairman of Committee...
Photon rockets and gravitational radiation
T. Damour
1994-12-21T23:59:59.000Z
The absence of gravitational radiation in Kinnersley's ``photon rocket'' solution of Einstein's equations is clarified by studying the mathematically well-defined problem of point-like photon rockets in Minkowski space (i.e. massive particles emitting null fluid anisotro\\-pically and accelerating because of the recoil). We explicitly compute the (uniquely defined) {\\it linearized} retarded gravitational waves emitted by such objects, which are the coherent superposition of the gravitational waves generated by the motion of the massive point-like rocket and of those generated by the energy-momentum distribution of the photon fluid. In the special case (corresponding to Kinnersley's solution) where the anisotropy of the photon emission is purely dipolar we find that the gravitational wave amplitude generated by the energy-momentum of the photons exactly cancels the usual $1/r$ gravitational wave amplitude generated by the accelerated motion of the rocket. More general photon anisotropies would, however, generate genuine gravitational radiation at infinity. Our explicit calculations show the compatibility between the non-radiative character of Kinnersley's solution and the currently used gravitational wave generation formalisms based on post-Minkowskian perturbation theory.
Electromagnetic pulse (EMP), Part I: Effects on field medical equipment
Vandre, R.H.; Klebers, J.; Tesche, F.M.; Blanchard, J.P. (Walter Reed Army Medical Center, Washington, DC (United States))
1993-04-01T23:59:59.000Z
The electromagnetic pulse (EMP) from a high-altitude nuclear detonation has the potential to cover an area as large as the continental United States with damaging levels of EMP radiation. In this study, two of seven items of medical equipment were damaged by an EMP simulator. Computer circuit analysis of 17 different items showed that 11 of the 17 items would be damaged by current surges on the power cords, while two would be damaged by current surges on external leads. This research showed that a field commander can expect approximately 65% of his electronic medical equipment to be damaged by a single nuclear detonation as far as 2,200 km away.
None
2011-04-25T23:59:59.000Z
Le conférencier Mons.Hofert parle des dangers et risques des radiations, le contrôle des zones et les précautions à prendre ( p.ex. film badge), comment mesurer les radiations etc.
Behavior of Torsional Alfven Waves and Field Line Resonance on Rotating Magnetars
Taishi Okita; Yasufumi Kojima
2005-10-31T23:59:59.000Z
Torsional Alfven waves are likely excited with bursts in rotating magnetars. These waves are probably propagated through corotating atmospheres toward a vacuum exterior. We have studied the physical effects of the azimuthal wave number and the characteristic height of the plasma medium on wave transmission. In this work, explicit calculations were carried out based on the three-layered cylindrical model. We found that the coupling strength between the internal shear and the external Alfven modes is drastically enhanced, when resonance occurs in the corotating plasma cavity. The spatial structure of the electromagnetic fields in the resonance cavity is also investigated when Alfven waves exhibit resonance.
Radiative Heat Transfer between Neighboring Particles
Alejandro Manjavacas; F. Javier Garcia de Abajo
2012-01-26T23:59:59.000Z
The near-field interaction between two neighboring particles is known to produce enhanced radiative heat transfer. We advance in the understanding of this phenomenon by including the full electromagnetic particle response, heat exchange with the environment, and important radiative corrections both in the distance dependence of the fields and in the particle absorption coefficients. We find that crossed terms of electric and magnetic interactions dominate the transfer rate between gold and SiC particles, whereas radiative corrections reduce it by several orders of magnitude even at small separations. Radiation away from the dimer can be strongly suppressed or enhanced at low and high temperatures, respectively. These effects must be taken into account for an accurate description of radiative heat transfer in nanostructured environments.
Corvino's construction using Brill waves
Domenico Giulini; Gustav Holzegel
2005-08-17T23:59:59.000Z
For two-black-hole time-symmetric initial data we consider the Corvino construction of gluing an exact Schwarzschild end. We propose to do this by using Brill waves. We address the question of whether this method can be used to reduce the overall energy, which seems to relate to the question of whether it can reduce the amount of `spurious' gravitational radiation. We find a positive answer at first order in the inverse gluing radius.
Perpendicular propagating electromagnetic envelope solitons in electron-positron-ion plasma
Jehan, Nusrat [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Salahuddin, M. [Pakistan Atomic Energy Commission, P.O. Box 1114, Islamabad 44000 (Pakistan); Mirza, Arshad M. [Department of Physics, Theoretical Plasma Physics Group, Quaid-i-Azam University, Islamabad 45320 (Pakistan)
2010-05-15T23:59:59.000Z
The nonlinear amplitude modulation of electromagnetic waves propagating perpendicular to the direction of ambient magnetic field in a uniform collisionless magnetized electron-positron-ion plasma is studied. The Krylov-Bogoliubov-Mitropolsky perturbation method is employed to derive nonlinear Schroedinger equation, which describes the amplitude dynamics of perturbed magnetic field. The modulation instability criterion reveals that the low frequency mode is always stable, whereas the high frequency mode becomes modulationally unstable for certain ranges of wave number and positron-to-electron density ratio. Furthermore, the positron-to-electron density ratio as well as the strength of ambient magnetic field is found to have significant effect on the solitary wave solutions of the nonlinear Schroedinger equation, namely, dark and bright envelope solitons.
Glenn, Timothy Scott, 1971-
2002-01-01T23:59:59.000Z
In recognition of the growing consideration of piezoelectric traveling-wave motors as suitable replacements for small-scale electromagnetic motors, the present work addresses two parallel objectives: (1) to develop an ...
Wave propagation in axion electrodynamics
Yakov Itin
2007-06-20T23:59:59.000Z
In this paper, the axion contribution to the electromagnetic wave propagation is studied. First we show how the axion electrodynamics model can be embedded into a premetric formalism of Maxwell electrodynamics. In this formalism, the axion field is not an arbitrary added Chern-Simon term of the Lagrangian, but emerges in a natural way as an irreducible part of a general constitutive tensor.We show that in order to represent the axion contribution to the wave propagation it is necessary to go beyond the geometric approximation, which is usually used in the premetric formalism. We derive a covariant dispersion relation for the axion modified electrodynamics. The wave propagation in this model is studied for an axion field with timelike, spacelike and null derivative covectors. The birefringence effect emerges in all these classes as a signal of Lorentz violation. This effect is however completely different from the ordinary birefringence appearing in classical optics and in premetric electrodynamics. The axion field does not simple double the ordinary light cone structure. In fact, it modifies the global topological structure of light cones surfaces. In CFJ-electrodynamics, such a modification results in violation of causality. In addition, the optical metrics in axion electrodynamics are not pseudo-Riemannian. In fact, for all types of the axion field, they are even non-Finslerian.
High Energy Photons, Neutrinos and Gravitational Waves from Gamma-Ray Bursts
P. Meszaros; S. Kobayashi; S. Razzaque; B. Zhang
2003-05-06T23:59:59.000Z
Most of the current knowldege about GRB is based on electromagnetic observations at MeV and lower energies. Here we focus on some recent theoretical work on GRB, in particular the higher energy (GeV-TeV) photon emission, and two potentially important non-electromagnetic channels, the TeV and higher energy neutrino signals, and the gravitational wave signals expected from GRB.
RADIATIVE TRANSFER SIMULATIONS OF NEUTRON STAR MERGER EJECTA
Tanaka, Masaomi [National Astronomical Observatory of Japan, Mitaka, Tokyo (Japan); Hotokezaka, Kenta, E-mail: masaomi.tanaka@nao.ac.jp, E-mail: hotoke@tap.scphys.kyoto-u.ac.jp [Department of Physics, Kyoto University, Kyoto (Japan)
2013-10-01T23:59:59.000Z
Mergers of binary neutron stars (NSs) are among the most promising gravitational wave (GW) sources. Next generation GW detectors are expected to detect signals from NS mergers within about 200 Mpc. The detection of electromagnetic wave (EM) counterparts is crucial to understanding the nature of GW sources. Among the possible EM emission from the NS merger, emission powered by radioactive r-process nuclei is one of the best targets for follow-up observations. However, predictions so far have not taken into account detailed r-process element abundances in the ejecta. We perform for the first time radiative transfer simulations of the NS merger ejecta including all the r-process elements from Ga to U. We show that the opacity of the NS merger ejecta is about ? = 10 cm{sup 2} g{sup –1}, which is higher than that of Fe-rich Type Ia supernova ejecta by a factor of ?100. As a result, the emission is fainter and lasts longer than previously expected. The spectra are almost featureless due to the high expansion velocity and bound-bound transitions of many different r-process elements. We demonstrate that the emission is brighter for a higher mass ratio of the two NSs and a softer equation of state adopted in the merger simulations. Because of the red color of the emission, follow-up observations in red optical and near-infrared (NIR) wavelengths will be the most efficient. At 200 Mpc, the expected brightness of the emission is i = 22-25 AB mag, z = 21-23 AB mag, and 21-24 AB mag in the NIR JHK bands. Thus, observations with wide-field 4 m- and 8 m-class optical telescopes and wide-field NIR space telescopes are necessary. We also argue that the emission powered by radioactive energy can be detected in the afterglow of nearby short gamma-ray bursts.
Gedney, S.D.
1987-09-01T23:59:59.000Z
The electromagnetic pulse (EMP) produced by a high-altitude nuclear blast presents a severe threat to electronic systems due to its extreme characteristics. To test the vulnerability of large systems, such as airplanes, missiles, or satellites, they must be subjected to a simulated EMP environment. One type of simulator that has been used to approximate the EMP environment is the Large Parallel-Plate Bounded-Wave Simulator. It is a guided-wave simulator which has properties of a transmission line and supports a single TEM model at sufficiently low frequencies. This type of simulator consists of finite-width parallel-plate waveguides, which are excited by a wave launcher and terminated by a wave receptor. This study addresses the field distribution within a finite-width parallel-plate waveguide that is matched to a conical tapered waveguide at either end. Characteristics of a parallel-plate bounded-wave EMP simulator were developed using scattering theory, thin-wire mesh approximation of the conducting surfaces, and the Numerical Electronics Code (NEC). Background is provided for readers to use the NEC as a tool in solving thin-wire scattering problems.
O. V. Veko; N. D Vlasii; Yu. A. Sitenko; E. M. Ovsiyuk; V. M. Red'kov
2014-10-30T23:59:59.000Z
Tetrad-based generalized complex formalism by Majorana--Oppenheimer is applied to treat electromagnetic field in extending de Sitter Universe in on-static spherically-symmetric coordinates. With the help of Wigner D-functions, we separate angular dependence in the complex vector field E_{j}(t,r)+i B_{j}(t,r) from (t,r)-dependence. The separation parameter arising here instead of frequency \\omega in Minkowski space-time is quantized, non-static geometry of the de Sitter model leads to definite dependence of electromagnetic modes on the time variable. Relation of 3-vector complex approach to 10-dimensional Duffin-Kemmer-Petiau formalism is considered. On this base, the electromagnetic waves of magnetic and electric type have been constructed in both approaches. In Duffin-Kemmer-Petiau approach, there are constructed gradient-type solutions in Lorentz gauge.
Zhukov, Alexander V., E-mail: alex-zhukov@sutd.edu.sg; Bouffanais, Roland [Singapore University of Technology and Design, 20 Dover Drive, Singapore 138682 (Singapore); Fedorov, E. G. [Volgograd State University of Architecture and Civil Engineering, 400074 Volgograd (Russian Federation); Belonenko, Mikhail B. [Laboratory of Nanotechnology, Volgograd Institute of Business, 400048 Volgograd (Russian Federation)
2014-05-28T23:59:59.000Z
Propagation of ultrashort laser pulses through various nano-objects has recently became an attractive topic for both theoretical and experimental studies due to its promising perspectives in a variety of problems of modern nanoelectronics. Here, we study the propagation of extremely short two-dimensional bipolar electromagnetic pulses in a heterogeneous array of semiconductor carbon nanotubes. Heterogeneity is defined as a region of enhanced electron density. The electromagnetic field in an array of nanotubes is described by Maxwell's equations, reduced to a multidimensional wave equation. Our numerical analysis shows the possibility of stable propagation of an electromagnetic pulse in a heterogeneous array of nanotubes. Furthermore, we establish that, depending on its speed of propagation, the pulse can pass through the area of increased electron concentration or be reflected therefrom.
Stochastic Gravitational Wave Background from Exoplanets
Ain, Anirban; Mitra, Sanjit
2015-01-01T23:59:59.000Z
Recent exoplanet surveys have predicted a very large population of planetary systems in our galaxy, more than one planet per star on the average, perhaps totalling about two hundred billion. These surveys, based on electro-magnetic observations, are limited to a very small neighbourhood of the solar system and the estimations rely on the observations of only a few thousand planets. On the other hand, orbital motions of planets around stars are expected to emit gravitational waves (GW), which could provide information about the planets not accessible to electro-magnetic astronomy. The cumulative effect of the planets, with periods ranging from few hours to several years, is expected to create a stochastic GW background (SGWB). We compute the characteristic GW strain of this background based on the observed distribution of planet parameters. We also show that the integrated extragalactic background is comparable or less than the galactic background at different frequencies. Our estimate shows that the net backg...
Caetano, Tiberio
particles is the so called cyclotron-resonance accel- erator 1,2 , where a coherent electromagnetic wave may wave-particle synchro- nism may be self-sustained throughout the accelerating pe- riod. Transverse the related fields tend to be small if the particle beam is of ap- propriate thickness 2 . As for longitudinal
Simple Scalings for Various Regimes of Electron Acceleration in Surface Plasma Waves
Riconda, C; Vialis, T; Grech, M
2015-01-01T23:59:59.000Z
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.
Artemyev, A. V., E-mail: ante0226@gmail.com; Vasiliev, A. A. [Space Research Institute, RAS, Moscow (Russian Federation); Mourenas, D.; Krasnoselskikh, V. V. [LPC2E/CNRS—University of Orleans, Orleans (France); Agapitov, O. V. [Space Sciences Laboratory, University of California, Berkeley, California 94720 (United States)
2014-10-15T23:59:59.000Z
In this paper, we consider high-energy electron scattering and nonlinear trapping by oblique whistler waves via the Landau resonance. We use recent spacecraft observations in the radiation belts to construct the whistler wave model. The main purpose of the paper is to provide an estimate of the critical wave amplitude for which the nonlinear wave-particle resonant interaction becomes more important than particle scattering. To this aim, we derive an analytical expression describing the particle scattering by large amplitude whistler waves and compare the corresponding effect with the nonlinear particle acceleration due to trapping. The latter is much more rare but the corresponding change of energy is substantially larger than energy jumps due to scattering. We show that for reasonable wave amplitudes ?10–100?mV/m of strong whistlers, the nonlinear effects are more important than the linear and nonlinear scattering for electrons with energies ?10–50?keV. We test the dependencies of the critical wave amplitude on system parameters (background plasma density, wave frequency, etc.). We discuss the role of obtained results for the theoretical description of the nonlinear wave amplification in radiation belts.
Massless Dirac Fermions in Electromagnetic Field
Ahmed Jellal; Abderrahim El Mouhafid; Mohammed Daoud
2012-02-12T23:59:59.000Z
We study the relations between massless Dirac fermions in an electromagnetic field and atoms in quantum optics. After getting the solutions of the energy spectrum, we show that it is possible to reproduce the 2D Dirac Hamiltonian, with all its quantum relativistic effects, in a controllable system as a single trapped ion through the Jaynes--Cummings and anti-Jaynes--Cummings models. Also we show that under certain conditions the evolution of the Dirac Hamiltonian provides us with Rashba spin-orbit and linear Dresselhaus couplings. Considering the multimode multiphoton Jaynes-Cummings model interacting with N modes of electromagnetic field prepared in general pure quantum states, we analyze the Rabi oscillation. Evaluating time evolution of the Dirac position operator, we determine the Zitterbewegung frequency and the corresponding oscillating term as function of the electromagnetic field.
Active remote detection of radioactivity based on electromagnetic signatures
Sprangle, P. [Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States) [Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States); University of Maryland, College Park, Maryland 20742-4111 (United States); Hafizi, B. [Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States)] [Plasma Physics Division, Naval Research Laboratory, Washington, District of Columbia 20375 (United States); Milchberg, H.; Nusinovich, G. [University of Maryland, College Park, Maryland 20742-4111 (United States)] [University of Maryland, College Park, Maryland 20742-4111 (United States); Zigler, A. [University of Maryland, College Park, Maryland 20742-4111 (United States) [University of Maryland, College Park, Maryland 20742-4111 (United States); Icarus Research, Inc., PO Box 30780, Bethesda, Maryland 20824-0780 (United States); The Hebrew University of Jerusalem, Jerusalem (Israel)
2014-01-15T23:59:59.000Z
This paper presents a new concept for the remote detection of radioactive materials. The concept is based on the detection of electromagnetic signatures in the vicinity of radioactive material and can enable stand-off detection at distances greater than 100?m. Radioactive materials emit gamma rays, which ionize the surrounding air. The ionized electrons rapidly attach to oxygen molecules forming O{sub 2}{sup ?} ions. The density of O{sub 2}{sup ?} around radioactive material can be several orders of magnitude greater than background levels. The elevated population of O{sub 2}{sup ?} extends several meters around the radioactive material. Electrons are easily photo-detached from O{sub 2}{sup ?} ions by laser radiation. The photo-detached electrons, in the presence of laser radiation, initiate avalanche ionization which results in a rapid increase in electron density. The rise in electron density induces a frequency modulation on a probe beam, which becomes a direct spectral signature for the presence of radioactive material.
Coda wave interferometry 1 Coda wave interferometry
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
Electromagnetic continuous casting project: Final report
Battles, J.E.; Rote, D.M.; Misra, B.; Praeg, W.F.; Hull, J.R.; Turner, L.R.; Shah, V.L.; Lari, R.J.; Gopalsami, N.; Wiencek, T.
1988-10-01T23:59:59.000Z
This report describes the work on development of an electromagnetic casting process for steel, which was carried out at Argonne National Laboratory between January 1985 and December 1987. This effort was concerned principally with analysis and design work on magnet technology, liquid metal feed system, coolant system, and sensors and process controllers. Experimentation primarily involved (1) electromagnetic studies to determine the conditions and controlling parameters for stable levitation and (2) feed-system studies to establish important parameters that control and influence fluid flow from the liquid metal source to the caster. 73 refs., 91 figs., 11 tabs.
Forces in electromagnetic field and gravitational field
Zihua Weng
2011-03-31T23:59:59.000Z
The force can be defined from the linear momentum in the gravitational field and electromagnetic field. But this definition can not cover the gradient of energy. In the paper, the force will be defined from the energy and torque in a new way, which involves the gravitational force, electromagnetic force, inertial force, gradient of energy, and some other new force terms etc. One of these new force terms can be used to explain why the solar wind varies velocity along the magnetic force line in the interplanetary space between the sun and the earth.
Bioelectromagnetic effects of the electromagnetic pulse (EMP)
Patrick, E.L.; Vault, W.L.
1990-03-01T23:59:59.000Z
The public has expressed concern about the biological effects and hazards of non-ionizing electromagnetic fields produced by the electro-magnetic pulse (EMP) simulators that simulate the EMP emanating from a high-altitude nuclear explosion. This paper provides a summary of the bioelectromagnetic effects literature up through the present, describes current occupational standards for workers exposed to the EMP environment, and discusses the use of medical surveillance as it relates to the potential human health hazards associated with exposure to the EMP environment.
Expanding, axisymmetric pure-radiation gravitational fields with a simple twist
B. V. Ivanov
2001-03-27T23:59:59.000Z
New expanding, axisymmetric pure-radiation solutions are found, exploiting the analogy with the Euler-Darboux equation for aligned colliding plane waves.
Ernest Valeo, Jay R. Johnson, Eun-Hwa and Cynthia Phillips
2012-03-13T23:59:59.000Z
A wide variety of plasma waves play an important role in the energization and loss of particles in the inner magnetosphere. Our ability to understand and model wave-particle interactions in this region requires improved knowledge of the spatial distribution and properties of these waves as well as improved understanding of how the waves depend on changes in solar wind forcing and/or geomagnetic activity. To this end, we have developed a two-dimensional, finite element code that solves the full wave equations in global magnetospheric geometry. The code describes three-dimensional wave structure including mode conversion when ULF, EMIC, and whistler waves are launched in a two-dimensional axisymmetric background plasma with general magnetic field topology. We illustrate the capabilities of the code by examining the role of plasmaspheric plumes on magnetosonic wave propagation; mode conversion at the ion-ion and Alfven resonances resulting from external, solar wind compressions; and wave structure and mode conversion of electromagnetic ion cyclotron waves launched in the equatorial magnetosphere, which propagate along the magnetic field lines toward the ionosphere. We also discuss advantages of the finite element method for resolving resonant structures, and how the model may be adapted to include nonlocal kinetic effects.
Guided wave methods and apparatus for nonlinear frequency generation
Durfee, III, Charles G. (Ann Arbor, MI); Rundquist, Andrew (Austin, TX); Kapteyn, Henry C. (Ann Arbor, MI); Murnane, Margaret M. (Ann Arbor, MI)
2000-01-01T23:59:59.000Z
Methods and apparatus are disclosed for the nonlinear generation of sum and difference frequencies of electromagnetic radiation propagating in a nonlinear material. A waveguide having a waveguide cavity contains the nonlinear material. Phase matching of the nonlinear generation is obtained by adjusting a waveguide propagation constant, the refractive index of the nonlinear material, or the waveguide mode in which the radiation propagates. Phase matching can be achieved even in isotropic nonlinear materials. A short-wavelength radiation source uses phase-matched nonlinear generation in a waveguide to produce high harmonics of a pulsed laser.
Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone
Yakovlev, Vadim
Modeling ofHybrid (Heat Radiation and Microwave) High Temperature Processing ofLimestone Shawn M (electromagnetic and thermal) modeling to cover practically valuable scenarios of hybrid (heat radiation is applied to the process of hybrid heating of cylindrical samples of limestone in Ceralink's MAT TM kiln
Scattering of terahertz radiation on a graphene-based nano-antenna
PolitÃ¨cnica de Catalunya, Universitat
Scattering of terahertz radiation on a graphene-based nano-antenna Ignacio Llatser, , Christian. Scattering of the terahertz radiation on a graphene-based nano-antenna is considered. Different electromagnetic models of graphene are discussed and applied to calculate extinction, scattering and absorption
Asymmetric radiative damping of low shear toroidal Alfvn eigenmodes R. M. Nyqvist and S. E. Sharapov
Asymmetric radiative damping of low shear toroidal Alfvén eigenmodes R. M. Nyqvist and S. E by the American Institute of Physics. Related Articles Influence of electromagnetic radiation on the power balance in a radiofrequency microdischarge with a hollow needle electrode Appl. Phys. Lett. 101, 144104 (2012) Plasma
Environmental Effects for Gravitational-wave Astrophysics
Enrico Barausse; Vitor Cardoso; Paolo Pani
2015-01-07T23:59:59.000Z
The upcoming detection of gravitational waves by terrestrial interferometers will usher in the era of gravitational-wave astronomy. This will be particularly true when space-based detectors will come of age and measure the mass and spin of massive black holes with exquisite precision and up to very high redshifts, thus allowing for better understanding of the symbiotic evolution of black holes with galaxies, and for high-precision tests of General Relativity in strong-field, highly dynamical regimes. Such ambitious goals require that astrophysical environmental pollution of gravitational-wave signals be constrained to negligible levels, so that neither detection nor estimation of the source parameters are significantly affected. Here, we consider the main sources for space-based detectors -- the inspiral, merger and ringdown of massive black-hole binaries and extreme mass-ratio inspirals -- and account for various effects on their gravitational waveforms, including electromagnetic fields, cosmological evolution, accretion disks, dark matter, "firewalls" and possible deviations from General Relativity. We discover that the black-hole quasinormal modes are sharply different in the presence of matter, but the ringdown signal observed by interferometers is typically unaffected. The effect of accretion disks and dark matter depends critically on their geometry and density profile, but is negligible for most sources, except for few special extreme mass-ratio inspirals. Electromagnetic fields and cosmological effects are always negligible. We finally explore the implications of our findings for proposed tests of General Relativity with gravitational waves, and conclude that environmental effects will not prevent the development of precision gravitational-wave astronomy.
Passive electromagnetic damping device for motion control of building structures
Palomera-Arias, Rogelio, 1972-
2005-01-01T23:59:59.000Z
The research presented in this thesis develops a new device for the passive control of motion in building structures: an electromagnetic damper. The electromagnetic damper is a self-excited device that provides a reaction ...
Reflection and Transmission of Pulsed Electromagnetic Fields through Multilayered
Oughstun, Kurt
Reflection and Transmission of Pulsed Electromagnetic Fields through Multilayered Biological Media- cally rigorous, physically correct description of the propagation of pulsed electromagnetic fields pulses through multilayered biological media consisting of three biological tissue layers rep- resenting
Electromagnetically induced transparency with broadband laser pulses D. D. Yavuz
Yavuz, Deniz
Electromagnetically induced transparency with broadband laser pulses D. D. Yavuz Department pulses inside an atomic medium using electromag- netically induced transparency. Extending the suggestion.65. k Over the last decade, counterintuitive optical effects using electromagnetically induced
Waveguide-based Ultrasonic and Far-field Electromagnetic Sensors...
Office of Environmental Management (EM)
ultrasonic and farfield electromagnetic sensors to measure key Enhanced Geothermal Systems (EGS) reservoir parameters, including directional temperature, pressure,...
Motor Packaging with Consideration of Electromagnetic and Material...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Documents & Publications Motor Packaging with Consideration of Electromagnetic and Material Characteristics Alnico and Ferrite Hybrid Excitation Electric Machines Wireless Charging...
WaveCurrent Interactions in Finite Depth JEROME A. SMITH
Smith, Jerome A.
WaveÂCurrent Interactions in Finite Depth JEROME A. SMITH Scripps Institution of Oceanography, La (Longuet-Higgins 1969; Hasselmann 1971; Garrett and Smith 1976; and many others). In particular, Hassel) changes in wave momentum that absorb some of the radiation stress gradients. Garrett and Smith (1976
Crutcher, R.I.; Buchanan, M.E.; Jones, R.W.
1989-08-01T23:59:59.000Z
The purpose of this report is to develop an engineering design package to protect the federal Emergency Management Agency (FEMA) National Radio System (FNARS) facilities from the effects of high-altitude electromagnetic pulses (HEMP). This report refers to the Louisiana State Emergency Operating Center (EOC) in Baton Rouge, Louisiana. This report addresses electromagnetic pulse (EMP) effects only, and disregards any condition in which radiation effects may be a factor. It has been established that, except for the source region of a surface burst, EMP effects of high-altitude bursts are more severe than comparable detonations in either air or surface regions. Any system hardened to withstand the more extreme EMP environment will survive the less severe conditions. The threatening environment will therefore be limited to HEMP situations. 76 figs., 2 tabs.
Structural composites with integrated electromagnetic functionality
Nemat-Nasser, Sia
Structural composites with integrated electromagnetic functionality Syrus C. Nemat-Nasser, Alireza, such as wires, into polymer-based or ceramic-based composites. In addition to desired structural properties, these materials may be leveraged for active tasks such as filtering. The advantages of such hybrid composites
Electromagnetic Composites at the Compton Scale
Frederick J. Mayer; John R. Reitz
2011-09-10T23:59:59.000Z
A new class of electromagnetic composite particles is proposed. The composites are very small (the Compton scale), potentially long-lived, would have unique interactions with atomic and nuclear systems, and, if they exist, could explain a number of otherwise anomalous and conflicting observations in diverse research areas.
Electromagnetic Wellbore Heating Ibrahim Agyemang1
Bohun, C. Sean
Chapter 5 Electromagnetic Wellbore Heating Ibrahim Agyemang1 , Matthew Bolton2 , Lloyd Bridge2 with the recovery of petroleum fluids from an oil reservoir using electrical energy. By its very nature this problem must deal with both the equations that describe the fluid flow as well as the heat flow equations
Turbulent Transition in an Electromagnetically Levitated Droplet
Mountziaris, T. J.
Turbulent Transition in an Electromagnetically Levitated Droplet Christina R. Rizer, Robert W a marked transition from laminar to turbulent flow, which can be observed by following the movement, will oscillate and break apart, marking the transition to turbulence. Using videos taken of these metal samples
FMM Code Libraries for Computational Electromagnetics
Maryland at College Park, University of
Max Optics, Inc. #12;MadMax Optics 2 Â· Stealth Â· Electromagnetic interference Â· Antennas on complex platforms Â Closed and open surfaces, complex materials Â· Fast, Direct Solvers for Ill-Conditioned Problems Â handle isotropic materials with closed surfaces Â Open surfaces still active area of research Â· Geometric
Optimizing Electromagnetic Hotspots in Plasmonic Bowtie Nanoantennae
Xiong, Qihua
Optimizing Electromagnetic Hotspots in Plasmonic Bowtie Nanoantennae Stephanie Dodson, Mohamed: Sensitivity is a key factor in the improvement of nanoparticle-based biosensors. Bowtie nanoantennae have resonance (LSPR)-based biosensing. In this work, optical bowtie nanoantennae with varying geometries were
Decomposition of Electromagnetic Q and P Media
Lindell, I V
2015-01-01T23:59:59.000Z
Two previously studied classes of electromagnetic media, labeled as those of Q media and P media, are decomposed according to the natural decomposition introduced by Hehl and Obukhov. Six special cases based on either non-existence or sole existence of the three Hehl-Obukhov components, are defined for both medium classes.
Fultz, Brent T. (Berkeley, CA)
1983-01-01T23:59:59.000Z
Apparatus is provided for detecting radiation such as gamma rays and X-rays generated in backscatter Mossbauer effect spectroscopy and X-ray spectrometry, which has a large "window" for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.
Fultz, B.T.
1980-12-05T23:59:59.000Z
Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.
Matched slow pulses using double electromagnetically induced transparency
Lvovsky, Alexander
Matched slow pulses using double electromagnetically induced transparency Andrew MacRae,* Geoff, 2008 We implement double electromagnetically induced transparency (DEIT) in rubidium vapor using Optical Society of America OCIS codes: 270.1670, 270.5585, 190.5530. Electromagnetically induced
Jin, Yao; Hu, Jiawei [Institute of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan Normal University, Changsha, Hunan 410081 (China); Yu, Hongwei, E-mail: hwyu@hunnu.edu.cn [Institute of Physics and Key Laboratory of Low Dimensional Quantum Structures and Quantum Control of Ministry of Education, Hunan Normal University, Changsha, Hunan 410081 (China); Center for Nonlinear Science and Department of Physics, Ningbo University, Ningbo, Zhejiang 315211 (China)
2014-05-15T23:59:59.000Z
We study, using the formalism proposed by Dalibard, Dupont-Roc and Cohen-Tannoudji, the contributions of the vacuum fluctuation and radiation reaction to the rate of change of the mean atomic energy for a circularly accelerated multilevel atom coupled to vacuum electromagnetic fields in the ultrarelativistic limit. We find that the balance between vacuum fluctuation and radiation reaction is broken, which causes spontaneous excitations of accelerated ground state atoms in vacuum. Unlike for a circularly accelerated atom coupled to vacuum scalar fields, the contribution of radiation reaction is also affected by acceleration, and this term takes the same form as that of a linearly accelerated atom coupled to vacuum electromagnetic fields. For the contribution of vacuum fluctuations, we find that in contrast to the linear acceleration case, terms proportional to the Planckian factor are replaced by those proportional to a non-Planck exponential term, and this indicates that the radiation perceived by a circularly orbiting observer is no longer thermal as is in the linear acceleration case. However, for an ensemble of two-level atoms, an effective temperature can be defined in terms of the atomic transition rates, which is found to be dependent on the transition frequency of the atom. Specifically, we calculate the effective temperature as a function of the transition frequency and find that in contrast to the case of circularly accelerated atoms coupled to the scalar field, the effective temperature in the current case is always larger than the Unruh temperature. -- Highlights: •We study the spontaneous excitation of a circularly accelerated atom. •Contribution of radiation reaction to the excitation is affected by acceleration. •The radiation perceived by a circularly orbiting observer is no longer thermal. •An effective temperature can be defined in terms of atomic transition rates. •Effective temperature is larger than Unruh temperature and frequency-dependent.
Paris-Sud XI, UniversitÃ© de
and the surrounding soft tissues are attenuating media, which might affect the radiofrequency signals measured systems and media, 43.20.Mv Waveguides, wave propagation in tubes and ducts, 43.20.Px Transient radiation and scattering, 43.40.Rj Radiation from vibrating structures into fluid media, 43.35.Pt Surface waves in solids
Saleem, H. [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Ahmad, Ali [Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Theoretical Plasma Physics Division, Pakistan Institute of Nuclear Science and Technology (PINSTECH), Islamabad (Pakistan); Khan, S. A. [National Centre for Physics (NCP), Quaid-i-Azam University Campus, Islamabad (Pakistan); Department of Physics, COMSATS Institute of Information Technology (CIIT), Islamabad (Pakistan); Department of Physics, Government College Bagh AJK (Pakistan)
2008-09-15T23:59:59.000Z
A coupled linear dispersion relation for the basic electrostatic and electromagnetic waves in the ultracold nonuniform magnetized dense plasmas has been obtained which interestingly is analogous to the classical case. The scales of macroscopic phenomena and the interparticle quantum interactions are discussed. It is important to point out that hydrodynamic models cannot take into account strong quantum effects and they are not applicable to very dense plasmas. The analysis is presented with applications to dense plasmas which are relevant to both laboratory and astrophysical environments.
Florida, University of
of both the incident lightning electromagnetic pulse (LEMP) and the effects of coupling of this field- mental validation using: 1) reduced-scale setups with LEMP and nuclear electromagnetic pulse (NEMP532 IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 51, NO. 3, AUGUST 2009 Lightning