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1

Investigation of electromagnetic welding  

E-Print Network [OSTI]

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 ...

Pressl, Daniel G. (Daniel Gerd)

2009-01-01T23:59:59.000Z

2

Vlf Electromagnetic Investigations Of The Crater And Central Dome Of Mount  

Open Energy Info (EERE)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home5b9fcbce19 NoPublic Utilities Address: 160 East 300 South Place: Salt Lake City,Division of Oil andInformationSt Helens,

3

IEEE TRANSACTIONS ON INSTRUMENTATION AND MEASUREMENT, VOL. 58, NO. 1, JANUARY 2009 129 Very-Low-Frequency Electromagnetic Field  

E-Print Network [OSTI]

, Walter J. Varhue, and Stephen Titcomb, Senior Member, IEEE Abstract--Naturally occurring electromagnetic and difficult to detect under normal conditions. These naturally occurring VLF electromagnetic events. This electronic system can be used to monitor VLF electromagnetic radiation in residential and occupational

Motai, Yuichi

4

Some unusual discrete VLF emissions observed at a low-latitude ground station at Agra  

E-Print Network [OSTI]

Some unusual discrete VLF emissions observed at a low-latitude ground station at Agra B. Singh February 1997 / Accepted: 17 February 1997 Abstract. A detailed analysis of the VLF emissions data obtained°1¢ N, L = 1.15) has yielded some unusual discrete VLF emissions of the rising type. These include (1

Paris-Sud XI, Université de

5

Models of ionospheric VLF absorption of powerful ground based transmitters  

E-Print Network [OSTI]

wind interaction with the magnetosphere injects particles into the magnetosphere which are subse hiss, lightning-generated whistlers, and radial diffusion [Thorne, 2010]. The steadier inner radiation-ionosphere waveguide. [4] Coherent signals from VLF transmitters are known to interact with radiation belt electrons

6

Investigation of the electromagnetic structure of. eta. and. eta. prime mesons by two-photon interactions  

SciTech Connect (OSTI)

The TPC/Two-Gamma facility at the SLAC {ital e}{sup +}{ital e}{sup {minus}} storage ring PEP was used to study the reactions {gamma}{gamma}{sup *}{r arrow}{eta} and {gamma}{gamma}{sup *}{r arrow}{eta}{prime}. The {eta}{gamma}{sup *}{gamma} and {eta}{prime}{gamma}{sup *}{gamma} transition form factors were measured as functions of {ital Q}{sup 2}, the negative of the invariant mass squared of the tagged photon, in the range 0.1{lt}{ital Q}{sup 2}{lt}7 GeV{sup 2}. These determinations of the electromagnetic structure of the {eta} and {eta}{prime} mesons are consistent with both vector-meson dominance and QCD. They also provide new measurements of the pseudoscalar mixing angle and decay constants.

Aihara, H.; Alston-Garnjost, M.; Avery, R.E.; Barbaro-Galtieri, A.; Barker, A.R.; Barnett, B.A.; Bauer, D.A.; Bay, A.; Bobbink, G.J.; Buchanan, C.D.; Buijs, A.; Caldwell, D.O.; Chao, H.; Chun, S.; Clark, A.R.; Cowan, G.D.; Crane, D.A.; Dahl, O.I.; Daoudi, M.; Derby, K.A.; Eastman, J.J.; Eberhard, P.H.; Edberg, T.K.; Eisner, A.M.; Erne, F.C.; Fairfield, K.H.; Hauptman, J.M.; Hofmann, W.; Hylen, J.; Kamae, T.; Kaye, H.S.; Kenney, R.W.; Khacheryan, S.; Kofler, R.R.; Langeveld, W.G.J.; Layter, J.G.; Lin, W.T.; Linde, F.L.; Loken, S.C.; Lu, A.; Lynch, G.R.; Madaras, R.J.; Magnuson, B.D.; Masek, G.E.; Mathis, L.G.; Matthews, J.A.J.; Maxfield, S.J.; Miller, E.S.; Moses, W.; Nygren, D.R.; Oddone, P.J.; Paar, H.P.; Park, S.K.; Pellett, D.E.; Pripstein, M.; Ronan, M.T.; Ross, R.R.; Rouse, F.R.; Schwitkis, K.A.; Sens, J.C.; Shapiro, G.; Shen, B.C.; Smith, J.R.; Steinman, J.S.; Stephens, R.W.; Stevenson, M.L.; Stork, D.H.; Strauss, M.G.; Sullivan, M.K.; Takahashi, T.; Toutounchi, S.; van Tyen, R.; TPC /Two-Gamma Collaboration

1990-01-08T23:59:59.000Z

7

Investigation of the Sintering Process Using Non-Contact Electromagnetic Acoustic Transducers  

SciTech Connect (OSTI)

In-situ characterizations of green state part density and sintering state have long been desired in the powder metal community. Recent advances in non-contact electromagnetic acoustic transducer (EMAT) technology have enabled in-situ monitoring of acoustic amplitude and velocity as sintering proceeds. Samples were made from elemental powders of Al (99.99%), Al (99.7%), Ag, (99.99%), Cu (99.99%) and Fe (99.9%). The powders were pressed in a uniaxial die and examined with acoustic waves for changes in velocity and amplitude during sintering for the samples containing Al, Ag, and Cu. The changes in acoustic properties were correlated with sample microstructures and mechanical properties. Evolution of a series of reverberating echoes during sintering is shown to provide information on the state of sintering, and changes in sintering kinetics as well as having the potential for detection of interior flaws.

James C. Foley; David K. Rehbein; Daniel J. Barnard

2001-05-30T23:59:59.000Z

8

An investigation of the usefulness of extremely low-frequency electromagnetic measurements for treaty verification  

SciTech Connect (OSTI)

From FY 1986 through FY 1988, we monitored extremely low-frequency (ELF) electromagnetic (EM) fields to determine whether these signals could be detected from underground nuclear explosions. Signals clearly related to underground tests were detected only when the ELF field sensors were located within 10 km of surface ground zero. Theoretical analysis, based on the results of these measurements, shows that the ELF impulse signals from underground nuclear tests are of longer duration than those from lightning sources and are, therefore, less efficient in exciting resonances in the earth-ionosphere cavity, even though the source strength for each may be the same. Thus, ELF signals from underground nuclear tests with yields of <150 kT are generally lower than the background signals caused by worldwide lightning activity. Our conclusion is that ELF monitoring probably will not be useful for detecting underground nuclear tests at distances >10 km from the tests. 16 refs., 24 figs., 3 tabs.

Sweeney, J.J.

1989-01-01T23:59:59.000Z

9

Transmitter-induced modulation of subionospheric VLF signals: Ionospheric heating rather than electron precipitation  

E-Print Network [OSTI]

path lies thousands of kilometers from the heating VLF transmitter. The 21.4 kHz transmitter NPM that the observed perturbations, despite occurring on a probe signal pathway that is 1750 km away from NPM at its point of closest approach, are due to direct ionospheric heating by the keyed VLF transmitter NPM

10

Investigation of electromagnetic launcher behavior for impact fusion. Annual report, May 1, 1984-April 30, 1985  

SciTech Connect (OSTI)

The second year of a 4-year program to develop an ultra-high velocity electromagnetic launcher has been completed, with significant progress made in the key technical areas. This lays firmly the cornerstone for major progress in Year 3 of the program. The launcher instrumentation and diagnostics system was developed. More than 20 launcher experiments were conducted using the SUVAC-I augmented launcher system. We tested our novel plasma generation technique using a lithium seeded propellant with encouraging success. We accelerated a 1.4 g projectile to 5.3 km/s in 1.6 m in the series. Unaugmented barrels for SUVAC-II were fabricated. The barrels were tested and commissioned with a total of 8 firings in single-stage configurations. The tests verified the basic soundness of the barrel mechanical and electrical design. Velocity up to 4.4 km/s was achieved with a 1.1 g projectile. Concurrently, we completed the fabrication, assembly and installation of SUVAC-II power supply (1 MJ) and its expanded control system. Experimentation with the multi-stage SUVAC-II launcher is expected to take place in the early part of Year 3. In the meantime, fabrication of the SUVAC-III power supply (an additional 0.4 MJ) has also been initiated.

Thio, Y.C.

1985-05-01T23:59:59.000Z

11

A broad spectral, interdisciplinary investigation of the electromagnetic properties of sea ice  

E-Print Network [OSTI]

This paper highlights the interrelationship of research completed by a team of investigators and presented in the several individual papers comprising this Special Section on the Office of Naval Research (ONR), Arlington, VA, Sponsored Sea Ice...

Jezek, K. C.; Perovich, D. K.; Golden, K. M.; Luther, C.; Barber, D. G.; Gogineni, Sivaprasad; Grenfell, T. C.; Jordan, A. K.; Mobley, C. D.; Nghiem, S. V.; Onstott, R. G.

1998-09-01T23:59:59.000Z

12

E-Print Network 3.0 - america vlf network Sample Search Results  

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

networks for monitoring VLF-LF radio signals is hoped for... Sciences Decrease in the electric intensity of VLFLF radio signals and possible connections P. F. Biagi1... ) to...

13

Comparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum  

E-Print Network [OSTI]

second fast latitude scan (near the solar maximum) with the wave observations during the first fast Experiments (URAP) of Ulysses during its first orbit, which occurred when the solar activity was approachingComparison of VLF Wave Activity in the Solar Wind During Solar Maximum and Minimum: Ulysses

California at Berkeley, University of

14

Studies of VLF radio waves for sudden ionospheric disturbances (SID) in Kashmir region  

SciTech Connect (OSTI)

It is recognized that the ionosphere may be sensitive to seismic effects, and the detection of ionospheric perturbations associated with seismicity would be useful for short term prediction of seismic events. To observe this effect, Indian Centre for Space Physics has installed an antenna and receiver system at Kashmir University to monitor the variation of the VLF signal transmitted from VTX. We present the preliminary results from this station.

Wani, M. R.; Iqbal, Naseer [Department of Physics, University of Kashmir, Srinagar (India); Sasmal, Sudipta [Indian Centre for Space Physics, Kolkata (India)

2010-10-20T23:59:59.000Z

15

RADIO SCIENCE, VOL. 49, 3643, doi:10.1002/2013RS005288, 2014 Rare examples of early VLF events observed in association  

E-Print Network [OSTI]

of the Earth's global electric circuit [Cummer et al., 2009]. The first GJs were observed from the groundRADIO SCIENCE, VOL. 49, 36­43, doi:10.1002/2013RS005288, 2014 Rare examples of early VLF events., T. Adachi, R.-R. Hsu, and A. B. Chen (2014), Rare examples of early VLF events observed

16

Electromagnetic Theory 1 /56 Electromagnetic Theory  

E-Print Network [OSTI]

Electromagnetic Theory 1 /56 Electromagnetic Theory Summary: · Maxwell's equations · EM Potentials · Equations of motion of particles in electromagnetic fields · Green's functions · Lienard-Weichert potentials · Spectral distribution of electromagnetic energy from an arbitrarily moving charge #12;Electromagnetic

Bicknell, Geoff

17

Electromagnetic Interrogation of Dielectric Materials 1  

E-Print Network [OSTI]

Electromagnetic Interrogation of Dielectric Materials 1 H.T. Banks M.W. Buksas Center for Research grant P200A40730. #12; Abstract We investigate time domain based electromagnetic inverse problems electromagnetic phenomenon. For our purposes, we categorize the materials and the models employed to describe them

18

A 3D finite-element modelling investigation into optimal survey parameters and direct imaging for marine controlled-source electromagnetic surveys  

E-Print Network [OSTI]

Relatively little is known about marine controlled-source electromagnetic surveys (MCSEM) used to detect hydrocarbon reservoirs. Typical MCSEM require the use of inversion to generate a model of the subsurface. We utilize a 3D finite-element forward...

Lau, Ryan

2007-09-17T23:59:59.000Z

19

Electromagnetic Geometry  

E-Print Network [OSTI]

We show that Maxwell's electromagnetism can be mapped into the Born-Infeld theory in a curved space-time, which depends only on the electromagnetic field in a specific way. This map is valid for any value of the two lorentz invariants $F$ and $G$ confirming that we have included all possible solutions of Maxwell's equations. Our result seems to show that specifying the dynamics and the space-time structure of a given theory can be viewed merely as a choice of representation to describe the physical system.

M. Novello; F. T. Falciano; E. Goulart

2011-11-08T23:59:59.000Z

20

Applications of the VLF Induction Method For Studying Some Volcanic...  

Open Energy Info (EERE)

investigation (100 m); and (3) the azimuths to two of the usable transmitters (NLK and NPM) are aligned favorably with most of the principal geologic features. Measurements of...

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Electromagnetic Reciprocity.  

SciTech Connect (OSTI)

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.

Aldridge, David F.

2014-11-01T23:59:59.000Z

22

Unmanned airborne vehicle (UAV): Flight testing and evaluation of two-channel E-field very low frequency (VLF) instrument  

SciTech Connect (OSTI)

Using VLF frequencies, transmitted by the Navy`s network, for airborne remote sensing of the earth`s electrical, magnetic characteristics was first considered by the United States Geological Survey (USGS) around the mid 1970s. The first VLF system was designed and developed by the USGS for installation and operation on a single engine, fixed wing aircraft used by the Branch of Geophysics for geophysical surveying. The system consisted of five channels. Two E-field channels with sensors consisting of a fixed vertical loaded dipole antenna with pre-amp mounted on top of the fuselage and a gyro stabilized horizontal loaded dipole antenna with pre-amp mounted on a tail boom. The three channel magnetic sensor consisted of three orthogonal coils mounted on the same gyro stabilized platform as the horizontal E-field antenna. The main features of the VLF receiver were: narrow band-width frequency selection using crystal filters, phase shifters for zeroing out system phase variances, phase-lock loops for generating real and quadrature gates, and synchronous detectors for generating real and quadrature outputs. In the mid 1990s the Branch of Geophysics designed and developed a two-channel E-field ground portable VLF system. The system was built using state-of-the-art circuit components and new concepts in circuit architecture. Small size, light weight, low power, durability, and reliability were key considerations in the design of the instrument. The primary purpose of the instrument was for collecting VLF data during ground surveys over small grid areas. Later the system was modified for installation on a Unmanned Airborne Vehicle (UAV). A series of three field trips were made to Easton, Maryland for testing and evaluating the system performance.

NONE

1998-12-01T23:59:59.000Z

23

Correlelations between the Anomalous Behaviour of the Ionosphere and the Seismic Events for VTX-MALDA VLF Propagation  

SciTech Connect (OSTI)

One of the most important application of the VLF signals is that it contains possible information about the lithosphere-ionosphere coupling. In other words, in near future, it may be possible to predict seismic events by judging signatures of VLF signals. In this paper, we present the result of the monitoring of the VLF signals collected in the Malda branch of ICSP, located in Malda, West Bengal, for four years (2005, 2007-09) and we try to find out the co-relations, if any, between the ionospheric activities and the earthquakes. Here we use that VLF signals which are transmitted from the VTX station (18.2 KHz), located near Vijayanarayanam in Tamilnadu, about 2290 km away from the receiver. To find out the co-relation of the ionospheric activities with the seismic events such as earthquake, first we have to study the average signal throughout the year. For this, we plot the so-called standardized calibration curve using the four years data. Here we use a total of 481 no. of data. To establish the co-relation between the ionospheric activities and the seismic events, we use the data of the year 2008 and we found that the deviations of the anomalous data are co-related with the seismic event. We found that the highest deviation takes place one day prior to the seismic events. We also calculated the 'D-layer preparation time'(DLPT) and the 'D-layer disappearance time'(DLDT) for the data of 2008 and tried to establish the co-relation between the anomalous DLPT and DLDT with the seismic events, if any. We compare our result with the VLF signals received from other places.

Ray, Suman; Sasmal, S. [Indian Centre for Space Physics, 43 Chalantika, Garia Station Road, Kolkata 700084 (India); Chakrabarti, S. K. [Indian Centre for Space Physics, 43 Chalantika, Garia Station Road, Kolkata 700084 (India); S. N. Bose National Centre for Basic Sciences, JD Block, Salt Lake, Kolkata 700098 (India); Choudhury, A. K. [Indian Centre for Space Physics, Malda Branch, Atul Market, Malda 731101 (India)

2010-10-20T23:59:59.000Z

24

Computational Electronics and Electromagnetics  

SciTech Connect (OSTI)

The Computational Electronics and Electromagnetics thrust area is a focal point for computer modeling activities in electronics and electromagnetics in the Electronics Engineering Department of Lawrence Livermore National Laboratory (LLNL). Traditionally, they have focused their efforts in technical areas of importance to existing and developing LLNL programs, and this continues to form the basis for much of their research. A relatively new and increasingly important emphasis for the thrust area is the formation of partnerships with industry and the application of their simulation technology and expertise to the solution of problems faced by industry. The activities of the thrust area fall into three broad categories: (1) the development of theoretical and computational models of electronic and electromagnetic phenomena, (2) the development of useful and robust software tools based on these models, and (3) the application of these tools to programmatic and industrial problems. In FY-92, they worked on projects in all of the areas outlined above. The object of their work on numerical electromagnetic algorithms continues to be the improvement of time-domain algorithms for electromagnetic simulation on unstructured conforming grids. The thrust area is also investigating various technologies for conforming-grid mesh generation to simplify the application of their advanced field solvers to design problems involving complicated geometries. They are developing a major code suite based on the three-dimensional (3-D), conforming-grid, time-domain code DSI3D. They continue to maintain and distribute the 3-D, finite-difference time-domain (FDTD) code TSAR, which is installed at several dozen university, government, and industry sites.

DeFord, J.F.

1993-03-01T23:59:59.000Z

25

Numerical modelling of VLF radio wave propagation through earth-ionosphere waveguide and its application to sudden ionospheric disturbances  

E-Print Network [OSTI]

In this thesis, we theoretically predict the normal characteristics of Very Low Frequency (3~30 kHz) radio wave propagation through Earth-ionosphere waveguide corresponding to normal behavior of the D-region ionosphere. We took the VLF narrow band data from the receivers of Indian Centre for Space Physics (ICSP) to validate our models. Detection of sudden ionospheric disturbances (SIDs) are common to all the measurements. We apply our theoretical models to infer the D-region characteristics and to reproduce the observed VLF signal behavior corresponding to such SIDs. We develop a code based on ray theory to simulate the diurnal behavior of VLF signals over short propagation paths (2000~3000 km). The diurnal variation from this code are comparable to the variation obtained from a more general Long Wave Propagation Capability (LWPC) code which is based on mode theory approach. We simulate the observational results obtained during the Total Solar Eclipse of July 22, 2009 in India. We also report and simulate a h...

Pal, Sujay

2015-01-01T23:59:59.000Z

26

Electromagnetic Field Theory  

E-Print Network [OSTI]

Electromagnetic Field Theory BO THID? UPSILON BOOKS #12;#12;ELECTROMAGNETIC FIELD THEORY #12;#12;Electromagnetic Field Theory BO THID? Swedish Institute of Space Physics and Department of Astronomy and Space, Sweden UPSILON BOOKS · COMMUNA AB · UPPSALA · SWEDEN #12;Also available ELECTROMAGNETIC FIELD THEORY

Hart, Gus

27

Structurally Electromagnetic Formation Flight (EMFF)  

E-Print Network [OSTI]

Structurally connected secondary mirror EMFF secondary mirror EMFF Design Electromagnetic Formation for a smaller, simpler system. µEMFF 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

de Weck, Olivier L.

28

Electromagnetic properties of neutrinos  

E-Print Network [OSTI]

A short review on electromagnetic properties of neutrinos is presented. In spite of many efforts in the theoretical and experimental studies of neutrino electromagnetic properties, they still remain one of the main puzzles related to neutrinos.

Carlo Giunti; Alexander Studenikin

2010-06-08T23:59:59.000Z

29

Electromagnetic Measurements at RHIC  

E-Print Network [OSTI]

Electromagnetic Measurements at RHIC Hideki Hamagaki Center for Nuclear Study University of Tokyo #12;2/10/2005 "Electromagnetic measurements at RHIC"@ICPAQGP 05 Hideki Hamagaki 2 Prologue · EM probe and where they are produced; #12;2/10/2005 "Electromagnetic measurements at RHIC"@ICPAQGP 05 Hideki Hamagaki

Hamagaki, Hideki

30

Electromagnetic Abdulaziz Hanif  

E-Print Network [OSTI]

Electromagnetic Propulsion Abdulaziz Hanif Electrical Engineering Department King Fahd University of spacecraft, which would be jolted through space by electromagnets, could take us farther than any of these other methods. When cooled to extremely low temperatures, electromagnets demonstrate an unusual behavior

Masoudi, Husain M.

31

Electromagnetic Measurements at RHIC  

E-Print Network [OSTI]

Electromagnetic Measurements at RHIC Hideki Hamagaki Center for Nuclear Study Graduate School of Science the University of Tokyo #12;2006/06/29 "Electromagnetic measurements at RHIC"@ATHIC 2006 Hideki;2006/06/29 "Electromagnetic measurements at RHIC"@ATHIC 2006 Hideki Hamagaki 3 Prologue ­ scope of EM measurements · EM

Hamagaki, Hideki

32

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

SciTech Connect (OSTI)

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.

Sati, Priti; Tripathi, V. K. [Indian Institute of Technology, Hauz Khas, Delhi 110054 (India)

2012-12-15T23:59:59.000Z

33

Overview Of Electromagnetic Methods Applied In Active Volcanic...  

Open Energy Info (EERE)

areas in the United States through electromagnetic geophysical studies received foundation from the many surveys done for geothermal exploration in the 1970's. Investigations...

34

Theory of electromagnetic fields  

E-Print Network [OSTI]

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.

Wolski, Andrzej

2011-01-01T23:59:59.000Z

35

Scattering by an electromagnetic radiation field  

E-Print Network [OSTI]

Motion of test particles in the gravitational field associated with an electromagnetic plane wave is investigated. The interaction with the radiation field is modeled by a force term {\\it \\`a la} Poynting-Robertson entering the equations of motion given by the 4-momentum density of radiation observed in the particle's rest frame with a multiplicative constant factor expressing the strength of the interaction itself. Explicit analytical solutions are obtained. Scattering of fields by the electromagnetic wave, i.e., scalar (spin 0), massless spin $\\frac12$ and electromagnetic (spin 1) fields, is studied too.

Donato Bini; Andrea Geralico

2014-08-21T23:59:59.000Z

36

Unbalanced electromagnetic forces  

E-Print Network [OSTI]

) . I :, jazdz g (Member) (Member) August 1974 -" ~ 5:. -. 62 ABSTRACT Unbalanced Electromagnetic Forces (August 1974) Craig Martin Hansen, B. S. , Texas A&M University Directed by: Dr. Attilio J. Giaroia Electromagnetic forces from moving... be deduced from the history of the development of an under- standing of electromagnetic forces. This is a relatively short history (starting in the late 1800's) filled with misunderstandings and pre]udices. This history can be divided into two eras: non...

Hansen, Craig Martin

2012-06-07T23:59:59.000Z

37

Meson electromagnetic form factors  

E-Print Network [OSTI]

The electromagnetic structure of the pseudoscalar meson nonet is completely described by the sophisticated Unitary&Analytic model, respecting all known theoretical properties of the corresponding form factors.

Stanislav Dubnicka; Anna Z. Dubnickova

2012-10-23T23:59:59.000Z

38

NISTHB 150-11 Electromagnetic  

E-Print Network [OSTI]

NISTHB 150-11 NVLAP Electromagnetic Compatibility and Telecommunications Bethany Hackett Bradley. #12;NISTHB 150-11 NVLAP Electromagnetic Compatibility and Telecommunications Bethany Hackett Bradley Programs Dennis Camell Electromagnetics Division Physical Measurement Laboratory http://dx.doi.org/10

39

Tunability enhanced electromagnetic wiggler  

DOE Patents [OSTI]

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. 14 figs.

Schlueter, R.D.; Deis, G.A.

1992-03-24T23:59:59.000Z

40

I. What is electromagnetic radiation and the electromagnetic spectrum?  

E-Print Network [OSTI]

i­1 I. What is electromagnetic radiation and the electromagnetic spectrum? What do light, X effects on matter. This "stuff" is called electromagnetic radiation, because it travels (radiates) and has electrical and magnetic effects. Electromagnetic radiation is the means for many of our interactions

Sitko, Michael L.

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

Purely electromagnetic spacetimes  

E-Print Network [OSTI]

Electrovacuum solutions devoid of usual mass sources are classified in the case of one, two and three commuting Killing vectors. Three branches of solutions exist. Electromagnetically induced mass terms appear in some of them.

B. V. Ivanov

2007-12-15T23:59:59.000Z

42

Electromagnetic rotational actuation.  

SciTech Connect (OSTI)

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.

Hogan, Alexander Lee

2010-08-01T23:59:59.000Z

43

Electromagnetic Field Creation During EWPT Nucleation With Lepton Currents  

E-Print Network [OSTI]

We include the electromagnetic currents from fermion degrees of freedom in the equations of motion for electroweak MSSM with a right-handed Stop that we have recently investigated. It is found that near the surface of the bubble walls there are important effects on the electromagnetic fields produced during bubble nucleation.

Leonard S. Kisslinger; Sameer Walawalkar; Ernest M. Henley; Mikkel B. Johnson

2005-10-11T23:59:59.000Z

44

Electromagnetic Effects in SDF Explosions  

SciTech Connect (OSTI)

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.

Reichenbach, H; Neuwald, P; Kuhl, A L

2010-02-12T23:59:59.000Z

45

EMG #121471 Electromagnetics, 25:679693, 2005  

E-Print Network [OSTI]

. Keywords electromagnetic compatibility, electromagnetic interference, aperture, cou- pling, finite compatibility (EMC) and electromagnetic interference (EMI) requirements, it is crucial to quantify

Ramahi, Omar

46

Electromagnetic properties of baryons  

SciTech Connect (OSTI)

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.

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

47

3. ELECTROMAGNETIC COMPATIBILITY Abstract --The electromagnetic interference between the  

E-Print Network [OSTI]

walls and tubes) and with strong EMI (Electromagnetic Interference). So it is ideal to use the power

Paris-Sud XI, Université de

48

Televisions, Video Privacy, and Powerline Electromagnetic Interference  

E-Print Network [OSTI]

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .iv Safe Use Guidelines, Electromagnetic Interference, and FCC Warning . . . . . . . . . . . . .v

Matsuoka, Yoky

49

Electromagnetic Radiation REFERENCE: Remote Sensing of  

E-Print Network [OSTI]

1 CHAPTER 2: Electromagnetic Radiation Principles REFERENCE: Remote Sensing of the Environment John;2 Electromagnetic Energy Interactions Energy recorded by remote sensing systems undergoes fundamental interactions, creating convectional currents in the atmosphere. c) Electromagnetic energy in the form of electromagnetic

Gilbes, Fernando

50

Electromagnetically Induced Flows Michiel de Reus  

E-Print Network [OSTI]

Electromagnetically Induced Flows in Water Michiel de Reus 8 maart 2013 () Electromagnetically Conclusion and future research () Electromagnetically Induced Flows 2 / 56 #12;1 Introduction 2 Maxwell Navier Stokes equations 5 Simulations 6 Conclusion and future research () Electromagnetically Induced

Vuik, Kees

51

Electromagnetic Wave Dynamics in  

E-Print Network [OSTI]

possibilities for strong localization of electromagnetic radiation in a dense and ultracold atomic gas sample an ultracold atomic rubidium gas sample, showing the coherent backscattering cone. The angular width of electrical excita- tion of condensed samples.3 Ongoing experimental and theoretical research directed toward

52

Electromagnetism and Gravitation  

E-Print Network [OSTI]

The classical concept of "mass density" is not fundamental to the quantum theory of matter. Therefore, mass density cannot be the source of gravitation. Here, we treat electromagnetic energy, momentum, and stress as its source. The resulting theory predicts that the gravitational potential near any charged elementary particle is many orders of magnitude greater than the Newtonian value.

Kenneth Dalton

1997-03-10T23:59:59.000Z

53

Electromagnetic pulsar spindown  

E-Print Network [OSTI]

We evaluate the result of the recent pioneering numerical simulations in Spitkovsky~2006 on the spindown of an oblique relativistic magnetic dipole rotator. Our discussion is based on our experience from two idealized cases, that of an aligned dipole rotator, and that of an oblique split-monopole rotator. We conclude that the issue of electromagnetic pulsar spindown may not have been resolved yet.

I. Contopoulos

2007-01-10T23:59:59.000Z

54

Electromagnetic probes of the QGP  

E-Print Network [OSTI]

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.

E. L. Bratkovskaya; O. Linnyk; W. Cassing

2014-09-15T23:59:59.000Z

55

Red shift in spectra of galaxies as a consequence of gravitational radiation of the same level as electromagnetic  

E-Print Network [OSTI]

In elaboration of the results presented earlier the red shift is also regarded in this investigation as a widening of electromagnetic radiation spectra, determined by the existence of gravitational radiation of a banded spectrum of the same level as electromagnetic.

S. I. Fisenko; I. S. Fisenko

2010-01-07T23:59:59.000Z

56

E-Print Network 3.0 - amplitude-modulated electromagnetic fields...  

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

; Engineering 8 Yerkes Summer Institute 2002 Before we begin our investigations into radio waves you should review the Summary: of the spectrum. Electromagnetic radiation...

57

Gravitation and Electromagnetism  

E-Print Network [OSTI]

The realms of gravitation, belonging to Classical Physics, and Electromagnetism, belonging to the Theory of the Electron and Quantum Mechanics have remained apart as two separate pillars, inspite of a century of effort by Physicists to reconcile them. In this paper it is argued that if we extend ideas of Classical spacetime to include in addition to non integrability non commutavity also, then such a reconcilation is possible.

B. G. Sidharth

2001-06-16T23:59:59.000Z

58

Fractional Electromagnetic Waves  

E-Print Network [OSTI]

In the present work we consider the electromagnetic wave equation in terms of the fractional derivative of the Caputo type. The order of the derivative being considered is 0 <\\gamma<1. A new parameter \\sigma, is introduced which characterizes the existence of the fractional components in the system. We analyze the fractional derivative with respect to time and space, for \\gamma = 1 and \\gamma = 1/2 cases.

J. F. Gmez; J. J. Rosales; J. J. Bernal; V. I. Tkach; M. Gua

2011-08-31T23:59:59.000Z

59

Quaternion Gravi-Electromagnetism  

E-Print Network [OSTI]

Defining the generalized charge, potential, current and generalized fields as complex quantities where real and imaginary parts represent gravitation and electromagnetism respectively, corresponding field equation, equation of motion and other quantum equations are derived in manifestly covariant manner. It has been shown that the field equations are invariant under Lorentz as well as duality transformations. It has been shown that the quaternionic formulation presented here remains invariant under quaternion transformations.

A. S. Rawat; O. P. S. Negi

2011-07-05T23:59:59.000Z

60

Banded electromagnetic stator core  

DOE Patents [OSTI]

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.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1996-06-11T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Banded electromagnetic stator core  

DOE Patents [OSTI]

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.

Fanning, A.W.; Gonzales, A.A.; Patel, M.R.; Olich, E.E.

1994-04-05T23:59:59.000Z

62

Pion Electromagnetic Form Factor up to 10 [GeV/]^2  

E-Print Network [OSTI]

The light-front approach is applied to calculate the electromagnetic current for quark-antiquark bound states for the pion. The pion electromagnetic form factor is obtnaide from the "+" and "-" components of the electromagnetic current in the Drell-Yan frame, with different models of the pi-q\\bar{q} vertex and the results for the pion electromagnetic form factor are compared with the experimental data up to 10 [GeV/c]^2 and anothers hadronic models. The rotational symmetry propreties of the pion electromagnetic current related with the zero-modes in the light-front are investigate.

J. P. B. C. de Melo

2005-07-26T23:59:59.000Z

63

Electromagnetic partner of the gravitational signal during accretion onto black holes  

E-Print Network [OSTI]

We investigate the generation of electromagnetic and gravitational radiation in the vicinity of a perturbed Schwarzschild black hole. The gravitational perturbations and the electromagnetic field are studied by solving the Teukolsky master equation with sources, which we take to be locally charged, radially infalling, matter. Our results show that, in addition to the gravitational wave generated as the matter falls into the black hole, there is also a burst of electromagnetic radiation. This electromagnetic field has a characteristic set of quasinormal frequencies, and the gravitational radiation has the quasinormal frequencies of a Schwarzschild black hole. This scenario allows us to compare the gravitational and electromagnetic signals that are generated by a common source.

Juan Carlos Degollado; Victor Gualajara; Claudia Moreno; Daro Nez

2014-10-21T23:59:59.000Z

64

Coherent hybrid electromagnetic field imaging  

DOE Patents [OSTI]

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.

Cooke, Bradly J. (Jemez Springs, NM); Guenther, David C. (Los Alamos, NM)

2008-08-26T23:59:59.000Z

65

An approach to electromagnetism from the general relativity  

E-Print Network [OSTI]

Classical gravitation is so similar to the electrostatic that the possible unification has been investigated for many years. Although electromagnetism is formulated successfully by quantum field theory, this paper proposes a simple approach to describe the electromagnetism from the macroscopic perspective of general relativity. The hypothesis is based on two charged particles that cause disturbance energy sufficient to disrupt the space-time and explain approximately Maxwell's equations. Therefore, with such this simple idea, we suggest the possibility that the geometric relationship between electromagnetism and gravitation is not yet fully exhausted.

Robert Monjo i Agut

2013-12-02T23:59:59.000Z

66

ELECTROMAGNETIC COMPATIBILITY AND RENEWABLE POWER FOR IMPLANTABLE NEUROSTIMULATORS  

E-Print Network [OSTI]

J, Bakker P: Electromagnetic interference from radiomaking electromagnetic interference neurostimulator functioninclude electromagnetic interference and battery failure. In

Pantchenko, Oxana S.

2012-01-01T23:59:59.000Z

67

Electromagnetic analysis of nanostructure dispersion in polymer matrices  

E-Print Network [OSTI]

P. R. , Enhanced electromagnetic interference shielding40] Chung D. D. L. Electromagnetic Interference Shieldingreinforcement, electromagnetic interference shielding, etc.

Pfeifer, Steven Charles; Pfeifer, Steven Charles

2012-01-01T23:59:59.000Z

68

Electromagnetic WavesElectromagnetic Waves In this chapter we will review selected properties of electromagnetic waves since  

E-Print Network [OSTI]

Electromagnetic WavesElectromagnetic Waves In this chapter we will review selected properties of electromagnetic waves since radar involves the transmission, propagation and scattering of EM waves by various is the electrostatic force between two point charges. #12;Electromagnetic WavesElectromagnetic Waves Electric fields

Rutledge, Steven

69

Electromagnetic field and cosmic censorship  

E-Print Network [OSTI]

We construct a gedanken experiment in which an extremal Kerr black hole interacts with a test electromagnetic field. Using Teukolsky's solutions for electromagnetic perturbations in Kerr spacetime, and the conservation laws imposed by the energy momentum tensor of the electromagnetic field and the Killing vectors of the spacetime, we prove that this interaction cannot convert the black hole into a naked singularity, thus cosmic censorship conjecture is not violated in this case.

Koray Dzta?

2014-04-09T23:59:59.000Z

70

Torsion and the Electromagnetic Field  

E-Print Network [OSTI]

In the framework of the teleparallel equivalent of general relativity, we study the dynamics of a gravitationally coupled electromagnetic field. It is shown that the electromagnetic field is able not only to couple to torsion, but also, through its energy-momentum tensor, to produce torsion. Furthermore, it is shown that the coupling of the electromagnetic field with torsion preserves the local gauge invariance of Maxwell's theory.

V. C. de Andrade; J. G. Pereira

1999-01-11T23:59:59.000Z

71

Electromagnetism on Anisotropic Fractals  

E-Print Network [OSTI]

We derive basic equations of electromagnetic fields in fractal media which are specified by three indepedent fractal dimensions {\\alpha}_{i} in the respective directions x_{i} (i=1,2,3) of the Cartesian space in which the fractal is embedded. To grasp the generally anisotropic structure of a fractal, we employ the product measure, so that the global forms of governing equations may be cast in forms involving conventional (integer-order) integrals, while the local forms are expressed through partial differential equations with derivatives of integer order but containing coefficients involving the {\\alpha}_{i}'s. First, a formulation based on product measures is shown to satisfy the four basic identities of vector calculus. This allows a generalization of the Green-Gauss and Stokes theorems as well as the charge conservation equation on anisotropic fractals. Then, pursuing the conceptual approach, we derive the Faraday and Amp\\`ere laws for such fractal media, which, along with two auxiliary null-divergence conditions, effectively give the modified Maxwell equations. Proceeding on a separate track, we employ a variational principle for electromagnetic fields, appropriately adapted to fractal media, to independently derive the same forms of these two laws. It is next found that the parabolic (for a conducting medium) and the hyperbolic (for a dielectric medium) equations involve modified gradient operators, while the Poynting vector has the same form as in the non-fractal case. Finally, Maxwell's electromagnetic stress tensor is reformulated for fractal systems. In all the cases, the derived equations for fractal media depend explicitly on fractal dimensions and reduce to conventional forms for continuous media with Euclidean geometries upon setting the dimensions to integers.

Martin Ostoja-Starzewski

2011-06-08T23:59:59.000Z

72

Asia Pacific Symposium of Applied Electromagnetics and Mechanics (APSAEM2010) Kuala Lumpur, Malaysia, 28-30th  

E-Print Network [OSTI]

, Malaysia, 28-30th July 2010 Reducing Electromagnetic Interference in Non-Isolated DC to DC Step JAMALUDIN*2 Investigation of the Electromagnetic interference (EMI) is important for design of a good power: electromagnetic interference, power converter, EMI, ohmic heating, high frequency. 1. Introduction In order

Hammerton, James

73

Electromagnetic Probes in PHENIX  

E-Print Network [OSTI]

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

Gabor David

2006-09-21T23:59:59.000Z

74

Gravitation and electromagnetism  

E-Print Network [OSTI]

Maxwell's equations comprise both electromagnetic and gravitational fields. The transverse part of the vector potential belongs to magnetism, the longitudinal one is concerned with gravitation. The Coulomb gauge indicates that longitudinal components of the fields propagate instantaneously. The delta-function singularity of the field of the divergence of the vector potential, referred to as the dilatation center, represents an elementary agent of gravitation. Viewing a particle as a source or a scattering center of the point dilatation, the Newton's gravitation law can be reproduced.

V. P. Dmitriyev

2002-07-23T23:59:59.000Z

75

Electromagnetic pump stator coil  

DOE Patents [OSTI]

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.

Fanning, A.W.; Dahl, L.R.

1996-06-25T23:59:59.000Z

76

Electromagnetic fuel injector  

SciTech Connect (OSTI)

This patent describes an electromagnetic fuel injector for an internal combustion engine having a valve axis and including a housing, a flat armature connected to a movable valve element arranged to cooperate with a valve seat, spring means for exerting a force in an axial direction on the armature, and electromagnetic means for exerting a force in an opposite direction on the armature when electrically energized. The improvement comprises: the spring means being a helical coil spring disposed in substantially coaxial alignment with the valve axis and having an end in compressive engagement with the armature, the final coil which includes the end of the coil spring being inclined axially outward at an angle relative to a plane normal to the axis of the spring so as to apply to the armature a greater axial spring force to one side of the valve axis than the other thereby to effect pivoting of the armature about a pivot, the pivot being determined by the location of the end of the coil spring.

Gieseking, J.H.

1987-04-28T23:59:59.000Z

77

Electromagnetic neutrino: a short review  

E-Print Network [OSTI]

A short review on selected issues related to the problem of neutrino electromagnetic properties is given. After a flash look at the theoretical basis of neutrino electromagnetic form factors, constraints on neutrino magnetic moments and electric millicharge from terrestrial experiments and astrophysical observations are discussed. We also focus on some recent studies of the problem and on perspectives.

Alexander I. Studenikin

2014-11-09T23:59:59.000Z

78

Electromagnetic reactions on light nuclei  

E-Print Network [OSTI]

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.

Sonia Bacca; Saori Pastore

2014-07-13T23:59:59.000Z

79

Airborne electromagnetic surveys as a reconnaissance technique...  

Open Energy Info (EERE)

Airborne electromagnetic surveys as a reconnaissance technique for geothermal exploration Abstract INPUT airborne electromagnetic (AEM) surveys were conducted during 1979 in five...

80

Nucleon Electromagnetic Form Factors  

SciTech Connect (OSTI)

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.

Marc Vanderhaeghen; Charles Perdrisat; Vina Punjabi

2007-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Electromagnetic Compatibility in Nuclear Power Plants  

SciTech Connect (OSTI)

Electromagnetic compatibility (EMC) has long been a key element of qualification for mission critical instrumentation and control (I&C) systems used by the U.S. military. The potential for disruption of safety-related I&C systems by electromagnetic interference (EMI), radio-frequency interference (RFI), or power surges is also an issue of concern for the nuclear industry. Experimental investigations of the potential vulnerability of advanced safety systems to EMI/RFI, coupled with studies of reported events at nuclear power plants (NPPs) that are attributed to EMI/RFI, confirm the safety significance of EMC for both analog and digital technology. As a result, Oak Ridge National Laboratory has been engaged in the development of the technical basis for guidance that addresses EMC for safety-related I&C systems in NPPs. This research has involved the identification of engineering practices to minimize the potential impact of EMI/RFI and power surges and an evaluation of the ambient electromagnetic environment at NPPs to tailor those practices for use by the nuclear industry. Recommendations for EMC guidance have been derived from these research findings and are summarized in this paper.

Ewing, P.D.; Kercel, S.W.; Korsah, K.; Wood, R.T.

1999-08-29T23:59:59.000Z

82

PHYSICS 416. Electromagnetism. Lecturer: Tim Gorringe.  

E-Print Network [OSTI]

PHYSICS 416. Electromagnetism. Lecturer: Tim Gorringe. Office: CP 273. Phone: 257-8740. Textbook: Electromagnetic Fields, R. Wangsness, 2nd Ed. Web page www.pa.uky.edu/gorringe/phy416/index.html Class hours: MWF-semester sequence on electromagnetic theory. 1 416/417 Course Objectives. The electromagnetic field binds electrons

MacAdam, Keith

83

PHYSICS 417. Electromagnetism. Lecturer: Tim Gorringe.  

E-Print Network [OSTI]

PHYSICS 417. Electromagnetism. Lecturer: Tim Gorringe. Office: CP273. Phone: 257-8740. Textbook: Electromagnetic Fields, R. Wangsness, 2nd Ed. Web page www.pa.uky.edu/gorringe/phy417/index.html Class hours: MWF-semester sequence on electromagnetic theory. 1 Course Objectives. The electromagnetic field binds electrons

MacAdam, Keith

84

Electromagnetic Signals from Bacterial DNA  

E-Print Network [OSTI]

Chemical reactions can be induced at a distance due to the propagation of electromagnetic signals during intermediate chemical stages. Although is is well known at optical frequencies, e.g. photosynthetic reactions, electromagnetic signals hold true for muck lower frequencies. In E. coli bacteria such electromagnetic signals can be generated by electric transitions between energy levels describing electrons moving around DNA loops. The electromagnetic signals between different bacteria within a community is a "wireless" version of intercellular communication found in bacterial communities connected by "nanowires". The wireless broadcasts can in principle be of both the AM and FM variety due to the magnetic flux periodicity in electron energy spectra in bacterial DNA orbital motions.

A. Widom; J. Swain; Y. N. Srivastava; S. Sivasubramanian

2012-02-09T23:59:59.000Z

85

Black Hole Thermodynamics and Electromagnetism  

E-Print Network [OSTI]

We show a strong parallel between the Hawking, Beckenstein black hole Thermodynamics and electromagnetism: When the gravitational coupling constant transform into the electromagnetic coupling constant, the Schwarzchild radius, the Beckenstein temperature, the Beckenstein decay time and the Planck mass transform to respectively the Compton wavelength, the Hagedorn temperature, the Compton time and a typical elementary particle mass. The reasons underlying this parallalism are then discussed in detail.

Burra G. Sidharth

2005-07-15T23:59:59.000Z

86

SOLAR NANTENNA ELECTROMAGNETIC COLLECTORS  

SciTech Connect (OSTI)

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.

Steven D. Novack; Dale K. Kotter; Dennis Slafer; Patrick Pinhero

2008-08-01T23:59:59.000Z

87

Electromagnetically driven peristaltic pump  

DOE Patents [OSTI]

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.

Marshall, Douglas W. (Blackfoot, ID)

2000-01-01T23:59:59.000Z

88

Electromagnetic Calorimeter for HADES  

E-Print Network [OSTI]

We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV. A purity of the identified leptons after the hadron rejection, resulting from simulations based on the test measurements, is better than 80% at momenta above 500 MeV/c, where time-of-flight cannot be used.

W. Czyzycki; E. Epple; L. Fabbietti; M. Golubeva; F. Guber; A. Ivashkin; M. Kajetanowicz; A. Krasa; F. Krizek; A. Kugler; K. Lapidus; E. Lisowski; J. Pietraszko; A. Reshetin; P. Salabura; Y. Sobolev; J. Stanislav; P. Tlusty; T. Torrieri; M. Traxler

2011-11-28T23:59:59.000Z

89

Electromagnetic Calorimeter for HADES  

E-Print Network [OSTI]

We propose to build the Electromagnetic calorimeter for the HADES di-lepton spectrometer. It will enable to measure the data on neutral meson production from nucleus-nucleus collisions, which are essential for interpretation of dilepton data, but are unknown in the energy range of planned experiments (2-10 GeV per nucleon). The calorimeter will improve the electron-hadron separation, and will be used for detection of photons from strange resonances in elementary and HI reactions. Detailed description of the detector layout, the support structure, the electronic readout and its performance studied via Monte Carlo simulations and series of dedicated test experiments is presented. The device will cover the total area of about 8 m^2 at polar angles between 12 and 45 degrees with almost full azimuthal coverage. The photon and electron energy resolution achieved in test experiments amounts to 5-6%/sqrt(E[GeV]) which is sufficient for the eta meson reconstruction with S/B ratio of 0.4% in Ni+Ni collisions at 8 AGeV....

Czyzycki, W; Fabbietti, L; Golubeva, M; Guber, F; Ivashkin, A; Kajetanowicz, M; Krasa, A; Krizek, F; Kugler, A; Lapidus, K; Lisowski, E; Pietraszko, J; Reshetin, A; Salabura, P; Sobolev, Y; Stanislav, J; Tlusty, P; Torrieri, T; Traxler, M

2011-01-01T23:59:59.000Z

90

Surface electromagnetic wave equations in a warm magnetized quantum plasma  

SciTech Connect (OSTI)

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.

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

91

Artificial Retina Project: Electromagnetic and Thermal Effects  

SciTech Connect (OSTI)

This award supported the investigation on electromagnetic and thermal effects associated with the artificial retina, designed in collaboration with national laboratories, universities, and private companies. Our work over the two years of support under this award has focused mainly on 1) Design of new telemetry coils for optimal power and data transfer between the implant and the external device while achieving a significant size reduction with respect to currently used coils; 2) feasibility study of the virtual electrode configuration 3) study the effect of pulse shape and duration on the stimulation efficacy.

Lazzi, Gianluca

2014-08-29T23:59:59.000Z

92

Electromagnetic corrections to pseudoscalar decay constants  

E-Print Network [OSTI]

The effects of electromagnetic interactions on pseudoscalar decay constants are investigated. Using a compact QED and QCD action we are able to resolve differences of about 0.1 MeV. We obtain the preliminary results f_pi^0-f_pi^+/- =0.09(3) MeV and f_D^0-f_D^+/- =0.79(11) MeV for light and charmed pseudoscalar decay constants on a N_f=2 nonperturbatively improved Sheikholeslami-Wohlert ensemble.

Benjamin Glaessle; Gunnar S. Bali

2011-11-16T23:59:59.000Z

93

The modified electromagnetism and the emergent longitudinal wave  

E-Print Network [OSTI]

The classical theory of electromagnetism has been revisited and the possibility of longitudinal photon wave is explored. It is shown that the emergence of longitudinal wave is a consequence of Lorenz gauge (condition) violation. Proca, Vlaenderen & Waser and Arbab theories are investigated.

Arbab I Arbab; Mudhahir Al-Ajmi

2014-01-22T23:59:59.000Z

94

Electromagnetic Interference from the ILC Beams  

SciTech Connect (OSTI)

Electromagnetic interference is an emerging problem of the future. This investigation analyzed the data collected from airborne radiation waves that caused electronic devices to fail. This investigation was set up at SLAC in End Station A and the data collected from the electromagnetic waves were received from antennas. In order to calibrate the antennas it required a signal generator to transmit the signals to the antenna and a digital oscilloscope to receive the radiation waves from the other antenna. The signal generator that was used was only able to generate signals between 1 and 1.45 GHz; therefore, the calibrations were not able to be completed. Instead, excel was used to create a curve fitting for the attenuation factors that were already factory calibrated. The function from the curve fitting was then used to extend the calibrations on the biconical and yagi antennas. A fast Fourier Transform was then ran in Matlab on the radiation waves received by the oscilloscope; in addition, the attenuation factors were calculated into the program to show the actual amplitudes of these radiation waves. For future research, the antennas will be manually calibrated and the results will be reanalyzed.

Brown, LaVonda N.; /Norfolk State U. /SLAC

2007-11-07T23:59:59.000Z

95

Electromagnetic low-energy constants in ChPT  

E-Print Network [OSTI]

We investigate three-flavour chiral perturbation theory including virtual photons in a limit where the strange quark mass is much larger than the external momenta and the up and down quark masses, and where the external fields are those of two-flavour chiral perturbation theory. In particular we work out the strange quark mass dependence of the electromagnetic two-flavour low-energy constants C and k_i. We expect that these relations will be useful for a more precise determination of the electromagnetic low-energy constants.

Christoph Haefeli; Mikhail A. Ivanov; Martin Schmid

2007-10-29T23:59:59.000Z

96

Electromagnetic compatibility in semiconductor manufacturing  

SciTech Connect (OSTI)

Electromagnetic Interference (EMI) causes problems in semiconductor manufacturing facilities that range from nuisances to major disruptions of production. In many instances, these issues are addressed in a reactionary rather than proactive manner by individuals who do not have the experience or the equipment necessary to combat EMI problems in a timely, cost effective manner. This approach leads to expensive retrofits, reduced equipment availability, long recovery times, and in some cases, line yield impacts. The goal of electromagnetic compatibility (EMC) in semiconductor manufacturing is to ensure that semiconductor process, metrology, and support equipment operate as intended without being affected by electromagnetic disturbances either transmitted through air (radiated interference), or transferred into the equipment via a conductive media (conducted interference). Rather than being neglected until serious issues arise, EMC should be considered in the early stages of facility design, in order to gain the most benefit at the lowest cost.

Montoya, J.A. [Intel Corp., Hillsboro, OR (United States)

1995-12-31T23:59:59.000Z

97

Electromagnetic radiation by gravitating bodies  

E-Print Network [OSTI]

Gravitating bodies in motion, regardless of their constitution, always produce electromagnetic radiation in the form of photon pairs. This phenomenon is an analog of the radiation caused by the motion of dielectric (or magnetic) bodies. It is a member of a wide class of phenomena named dynamical Casimir effects, and it may be viewed as the squeezing of the electromagnetic vacuum. Production of photon pairs is a purely quantum-mechanical effect. Unfortunately, as we show, the emitted radiation is extremely weak as compared to radiation produced by other mechanisms.

Iwo Bialynicki-Birula; Zofia Bialynicka-Birula

2008-05-06T23:59:59.000Z

98

Perfectly Reflectionless Omnidirectional Electromagnetic Absorber  

E-Print Network [OSTI]

We demonstrate the existence of metamaterial blueprints describing, and fundamental limitations concerning, perfectly reflectionless omnidirectional electromagnetic absorbers (PR-OEMA). Previous attempts to define PR-OEMA blueprints have led to active (gain), rather than passive, media. We explain this fact and unveil new, distinct limitations of true PR-OEMA devices including the appearance of an "electromagnetic horizon" on physical solutions. As practical alternatives, we introduce two new OEMA blueprints. While these two blueprints do not correspond to reflectionless media, they are effective in absorbing incident waves in a manner robust to incident wave diversity.

Sainath, Kamalesh

2014-01-01T23:59:59.000Z

99

Electromagnetic-gravitational cross-sections in external electromagnetic fields  

E-Print Network [OSTI]

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.

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

100

Experimental time-domain controlled source electromagnetic induction for highly conductive targets detection and discrimination  

E-Print Network [OSTI]

The response of geological materials at the scale of meters and the response of buried targets of different shapes and sizes using controlled-source electromagnetic induction (CSEM) is investigated. This dissertation focuses on three topics; i) frac...

Benavides Iglesias, Alfonso

2007-09-17T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


101

Three dimensional electromagnetic wavepackets in a plasma: Spatiotemporal modulational instability  

SciTech Connect (OSTI)

The nonlinear interaction of an intense electromagnetic beam with relativistic collisionless unmagnetized plasma is investigated by invoking the reductive perturbation technique, resting on the model of three-dimensional nonlinear Schrdinger (NLS) equation with cubic nonlinearity which incorporates the effects of self-focusing, self-phase modulation, and diffraction on wave propagation. Relying on the derived NLS equation, the occurrence of spatiotemporal modulational instability is investigated in detail.

Borhanian, J.; Hosseini Faradonbe, F. [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P. O. Box 179, Ardabil (Iran, Islamic Republic of)] [Department of Physics, Faculty of Science, University of Mohaghegh Ardabili, P. O. Box 179, Ardabil (Iran, Islamic Republic of)

2014-04-15T23:59:59.000Z

102

Self-Duality in Nonlinear Electromagnetism  

E-Print Network [OSTI]

We discuss duality invariant interactions between electromagnetic fields and matter. The case of scalar fields is treated in some detail.

Mary K. Gaillard; Bruno Zumino

1997-05-28T23:59:59.000Z

103

Electromagnetic design considerations for fast acting controllers  

SciTech Connect (OSTI)

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.

Woodford, D.A. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)

1996-07-01T23:59:59.000Z

104

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 55, NO. 2, APRIL 2013 395 Electromagnetic Interference Analysis of  

E-Print Network [OSTI]

to electromagnetic interference (EMI) is becoming a critical aspect of signal integrity analysis. For mod- eling in high-speed packages [2]. As a result, effi- cient and accurate electromagnetic interference (EMIIEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 55, NO. 2, APRIL 2013 395 Electromagnetic

Roy, Sourajeet

105

Why Study Electromagnetics: The First Unit in an Undergraduate Electromagnetics Course  

E-Print Network [OSTI]

1 Why Study Electromagnetics: The First Unit in an Undergraduate Electromagnetics Course Allen unification of electric and magnetic fields predicting electromagnetic wave phenomena which Nobel Laureate: "Of what relevance is the study of electromagnetics to our modern society?" The goal of this unit

Taflove, Allen

106

STIMULATED ELECTROMAGNETIC EMISSIONS BY HIGH-FREQUENCY ELECTROMAGNETIC PUMPING OF THE  

E-Print Network [OSTI]

STIMULATED ELECTROMAGNETIC EMISSIONS BY HIGH-FREQUENCY ELECTROMAGNETIC PUMPING OF THE IONOSPHERIC.S.A. Abstract. A high frequency electromagnetic pump wave transmitted into the ionospheric plasma from the ground can stimulate electromagnetic radiation with frequencies around that of the ionospher- ically

107

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1a) The Null Energy Condition on an energy = (k, 0, 0, k), show that the energy-momentum tensor Tµ = 1 4 Fµ F - 1 4µ F F (1) for electromagnetism if the equality kµ k Tµ = 0 is attained. (2) Show that the energy-momentum tensor for electromagnetism can

Pope, Christopher

108

Course Outline Physics 433: Electromagnetism II  

E-Print Network [OSTI]

Course Outline Physics 433: Electromagnetism II Spring 2014 Prof. Keun Hyuk "Ken" Ahn 483 Tiernan of this course is on the elementary concepts of electromagnetic fields. Upon completion of the course, students are expected to be capable of using the Maxwell equations to calculate simple electromagnetic problems, ranging

109

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1a) Show that the energy-momentum tensor for the electromagnetic field is tracefree, i.e. Tµ µ = 0. What would happen, in a spacetime dimension d = 4? (Assume) Show that the energy-momentum tensor for the electromagnetic field can be written as Tµ = 1 8 (Fµ F

Pope, Christopher

110

Electromagnetic Corrections in Staggered Chiral Perturbation Theory  

E-Print Network [OSTI]

Electromagnetic Corrections in Staggered Chiral Perturbation Theory C. Bernard and E.D. Freeland perturbation theory including electromagnetism, and discuss the extent to which quenched-photon simulations can-lat]17Nov2010 #12;Electromagnetic Corrections in Staggered Chiral Perturbation Theory E.D. Freeland 1

Bernard, Claude

111

Physics 4: Introductory Physics Electromagnetism and Light  

E-Print Network [OSTI]

Physics 4: Introductory Physics Electromagnetism and Light Professor Jeffrey D. Richman Department: Electromagnetism and Light Welcome to Physics 4! What is your goal in life? If it is to become an engineer or to pursue a career in science, this is a key class for you. Understanding electromagnetism and light

Fygenson, Deborah Kuchnir

112

611: Electromagnetic Theory Problem Sheet 5  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 5 (1) Consider the expression for the electric field due · dS over a spherical surface that encloses the moving charge. (2a) Consider an electromagnetic wave density and the Poynting vector. (2c) Repeat the steps in (2a) and (2b) for an electromagnetic wave

Pope, Christopher

113

611: Electromagnetic Theory Problem Sheet 6  

E-Print Network [OSTI]

611: Electromagnetic Theory Problem Sheet 6 (1) Consider the expression for the electric field due · dS over a spherical surface that encloses the moving charge. (2a) Consider an electromagnetic wave density and the Poynting vector. (2c) Repeat the steps in (2a) and (2b) for an electromagnetic wave

Pope, Christopher

114

Electromagnetics from Simulation to Optimal Design  

E-Print Network [OSTI]

1 Electromagnetics from Simulation to Optimal Design Christian Hafner Laboratory for Electromagnetic Fields and Microwave Electronics (IFH) ETH Zurich (Switzerland) Lab: http://www.ifh.ee.ethz.ch COG 23, 2013 #12;2 IFH courses · Advanced engineering electromagnetics (Leuchtmann, start spring 2014

Lang, Annika

115

Electromagnetic Formation Flight of Satellite Arrays  

E-Print Network [OSTI]

Electromagnetic Formation Flight of Satellite Arrays Daniel W. Kwon and David W. Miller February 2005 SSL # 2-05 #12;#12;Electromagnetic Formation Flight of Satellite Arrays By DANIEL W. KWON S;#12;Electromagnetic Formation Flight of Satellite Arrays by DANIEL W. KWON Submitted to the Department of Aeronautics

116

Characterization of the coherent noise, electromagnetic compatibility and electromagnetic interference of the ATLAS EM calorimeter Front End Board  

E-Print Network [OSTI]

Characterization of the coherent noise, electromagnetic compatibility and electromagnetic interference of the ATLAS EM calorimeter Front End Board

Chase, B E; Lanni, F; Makowiecki, D S; Radeka, V; Rescia, S; Takai, H; Bn, J; Parsons, J; Sippach, W

1999-01-01T23:59:59.000Z

117

Strong permanent magnet-assisted electromagnetic undulator  

DOE Patents [OSTI]

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles.

Halbach, Klaus (Berkeley, CA)

1988-01-01T23:59:59.000Z

118

Some Wave Equations for Electromagnetism and Gravitation  

E-Print Network [OSTI]

The paper studies the inferences of wave equations for electromagnetic fields when there are gravitational fields at the same time. In the description with the algebra of octonions, the inferences of wave equations are identical with that in conventional electromagnetic theory with vector terminology. By means of the octonion exponential function, we can draw out that the electromagnetic waves are transverse waves in a vacuum, and rephrase the law of reflection, Snell's law, Fresnel formula, and total internal reflection etc. The study claims that the theoretical results of wave equations for electromagnetic strength keep unchanged in the case for coexistence of gravitational and electromagnetic fields. Meanwhile the electric and magnetic components of electromagnetic waves can not be determined simultaneously in electromagnetic fields.

Zi-Hua Weng

2010-08-11T23:59:59.000Z

119

Transient electromagnetic interference in substations  

SciTech Connect (OSTI)

Electromagnetic interference levels on sensitive electronic equipment are quantified experimentally and theoretically in air and gas insulated substations of different voltages. Measurement techniques for recording interference voltages and currents and electric and magnetic fields are reviewed and actual interference data are summarized. Conducted and radiated interference coupling mechanisms and levels in substation control wiring are described using both measurement results and electromagnetic models validated against measurements. The nominal maximum field and control wire interference levels expected in the switchyard and inside the control house from switching operations, faults, and an average lightning strike are estimated using high frequency transient coupling models. Comparisons with standards are made and recommendations given concerning equipment shielding and surge protection.

Wiggins, C.M.; Thomas, D.E.; Nickel, F.S.; Salas, T.M. (BDM International, Inc., Albuquerque, NM (United States)); Wright, S.E. (Electric Power Research Inst., Palo Alto, CA (United States))

1994-10-01T23:59:59.000Z

120

Dark Energy, Gravitation and Electromagnetism  

E-Print Network [OSTI]

In the context of the fact that the existence of dark energy causing the accelerated expansion of the universe has been confirmed by the WMAP and the Sloan Digital Sky Survey, we re-examine gravitation itself, starting with the formulation of Sakharov and show that it is possible to obtain gravitation in terms of the electromagnetic charge of elementary particles, once the ZPF and its effects at the Compton scale are taken into account.

B. G. Sidharth

2004-01-08T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Laminated electromagnetic pump stator core  

DOE Patents [OSTI]

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.

Fanning, A.W.

1995-08-08T23:59:59.000Z

122

Shielding effectiveness against electromagnetic interference  

SciTech Connect (OSTI)

The use of metal-filled and metal-coated plastics and other modified dielectric materials to replace metals for enclosures has created a need to test these materials for their electromagnetic interference (EMI) shielding effectiveness (SE). Shielding effectiveness involves a variety of electromagnetic environments, and useful data can be obtained from tests that carefully limit the environment to that of a plane wave. Such an environment can be created in a circular or rectangular transmission line. Two such transmission line test fixtures, which hold samples of the material to be tested, have been developed. The fixtures described in this report are the National Bureau of Standards (NBS) coaxial transverse electromagnetic (TEM) cell, and a dual TEM cell constructed at ORNL from a design suggested by the NBS. The NBS coaxial fixture is an improved version of the device recommended by the American Society for Testing and Materials (ASTM). The problems associated with measuring SE are well described in the literature. The two methods described here are the result of years of work to establish procedures and instrumentation that will produce acceptable data.

Googe, J.M.; Hess, R.A.

1987-10-01T23:59:59.000Z

123

The nature of electromagnetic energy  

E-Print Network [OSTI]

The nature of the electromagnetic (EM) energy for general charge and current distributions is analyzed. There are two well known forms for calculating EM energy as the integral over all space of either the electromagnetic fields: $u_{\\bf EB}=({\\bf E\\bcdot D+B\\bcdot H})/8\\pi$, or the electromagnetic potentials and charge-current densities: $u_{\\rho{\\bf A}}=1/2(\\rho\\phi+{\\bf j\\bcdot A})$. We discuss the appropriate use of each of these forms in calculating the total EM energy and the EM energy within a limited volume. We conclude that only the form $u_{\\bf EB}$ can be considered as a suitable EM energy density, while either form can be integrated to find the total EM energy. However, bounding surface integrals (if they don't vanish) must be included when using the $u_{\\bf EB}$ form. Including these surface integrals resolves some seeming paradoxes in the energy of electric or magnetic dipoles in uniform fields

Jerrold Franklin

2007-07-23T23:59:59.000Z

124

Effects of Electromagnetic Field on the Dynamical Instability of Expansionfree Gravitational Collapse  

E-Print Network [OSTI]

In this paper, we discuss the effects of electromagnetic field on the dynamical instability of a spherically symmetric expansionfree gravitational collapse. Darmois junction conditions are formulated by matching interior spherically symmetric spacetime to exterior Reissner-Nordstr$\\ddot{o}$m spacetime. We investigate the role of different terms in the dynamical equation at Newtonian and post Newtonian regimes by using perturbation scheme. It is concluded that instability range depends upon pressure anisotropy, radial profile of energy density and electromagnetic field, but not on the adiabatic index $\\Gamma$. In particular, the electromagnetic field reduces the unstable region.

M. Sharif; M. Azam

2013-05-31T23:59:59.000Z

125

Electromagnetic wave scattering by Schwarzschild black holes  

E-Print Network [OSTI]

We analyze the scattering of a planar monochromatic electromagnetic wave incident upon a Schwarzschild black hole. We obtain accurate numerical results from the partial wave method for the electromagnetic scattering cross section, and show that they are in excellent agreement with analytical approximations. The scattering of electromagnetic waves is compared with the scattering of scalar, spinor and gravitational waves. We present a unified picture of the scattering of all massless fields for the first time.

Lus C. B. Crispino; Sam R. Dolan; Ednilton S. Oliveira

2009-05-20T23:59:59.000Z

126

Electromagnetic interactions at RHIC and LHC  

E-Print Network [OSTI]

At LHC energies the Lorentz factor will be 3400 for the Pb + Pb collisions and the electromagnetic interactions will play important roles. Cross sections for the electromagnetic particle productions are very large and can not be ignored for the lifetimes of the beams and background. In this article, we are going to study some of the electromagnetic processes at RHIC and LHC and show the cross section calculations of the electron-positron pair production with the giant dipole resonance of the ions.

M. C. Guclu

2008-11-15T23:59:59.000Z

127

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...

128

6.630 Electromagnetic Theory, Fall 2002  

E-Print Network [OSTI]

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, ...

Kong, Jin Au, 1942-

129

22.105 Electromagnetic Interactions, Fall 1998  

E-Print Network [OSTI]

Principles and applications of electromagnetism, starting from Maxwell's equations, with emphasis on phenomena important to nuclear engineering and radiation sciences. Solution methods for electrostatic and magnetostatic ...

Hutchinson, I. H. (Ian H.)

130

Relativistic approach to electromagnetic imaging  

E-Print Network [OSTI]

A novel imaging principle based on the interaction of electromagnetic waves with a beam of relativistic electrons is proposed. Wave-particle interaction is assumed to take place in a small spatial domain, so that each electron is only briefly accelerated by the incident field. In the one-dimensional case the spatial distribution of the source density can be directly observed in the temporal spectrum of the scattered field. Whereas, in the two-dimensional case the relation between the source and the spectrum is shown to be approximately the Radon transform.

Budko, N

2004-01-01T23:59:59.000Z

131

Relativistic approach to electromagnetic imaging  

E-Print Network [OSTI]

A novel imaging principle based on the interaction of electromagnetic waves with a beam of relativistic electrons is proposed. Wave-particle interaction is assumed to take place in a small spatial domain, so that each electron is only briefly accelerated by the incident field. In the one-dimensional case the spatial distribution of the source density can be directly observed in the temporal spectrum of the scattered field. Whereas, in the two-dimensional case the relation between the source and the spectrum is shown to be approximately the Radon transform.

Neil Budko

2004-03-11T23:59:59.000Z

132

Electromagnetic effects on transportation systems  

SciTech Connect (OSTI)

Electronic and electrical system protection design can be used to eliminate deleterious effects from lightning, electromagnetic interference, and electrostatic discharges. Evaluation of conventional lightning protection systems using advanced computational modeling in conjunction with rocket-triggered lightning tests suggests that currently used lightning protection system design rules are inadequate and that significant improvements in best practices used for electronic and electrical system protection designs are possible. A case study of lightning induced upset and failure of a railway signal and control system is sketched.

Morris, M.E.; Dinallo, M.A.

1996-05-01T23:59:59.000Z

133

Quantum modulation against electromagnetic interference  

E-Print Network [OSTI]

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.

Juan Carlos Garcia-Escartin

2014-11-26T23:59:59.000Z

134

Electromagnetic properties of massive neutrinos  

SciTech Connect (OSTI)

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.

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

135

Electromagnetic dissociation of relativistic [sup 28]Si by nucleon emission  

SciTech Connect (OSTI)

A detailed study of the electromagnetic dissociation of [sup 28]Si by nucleon emission at E[sub lab]/A = 14.6 (GeV/nucleon was carried out with [sup 28]Si beams interacting on [sup 208]Pb). [sup 120]Sn. [sup 64]C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z[sub T] and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of [sup 28]Si [yields] p+[sup 27]Al and [sup 28]Si [yields] n+[sup 27]Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targets peak near the isovector giant dipole resonance in [sup 28]Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear [sup 28]Si([sub [gamma],p])[sup 27]Al and [sup 28]Si([sub [gamma],n])[sup 27]Si. The possibilities of observing double giant dipole resonance excitations in [sup 28]Si have been investigated with cross section measurements as well as with excitation energy reconstruction.

Sonnadara, U.J.

1992-12-01T23:59:59.000Z

136

Electromagnetic dissociation of relativistic {sup 28}Si by nucleon emission  

SciTech Connect (OSTI)

A detailed study of the electromagnetic dissociation of {sup 28}Si by nucleon emission at E{sub lab}/A = 14.6 (GeV/nucleon was carried out with {sup 28}Si beams interacting on {sup 208}Pb). {sup 120}Sn. {sup 64}C targets. The measurements apparatus consists of detectors in the target area which measure the energy and charged multiplicity, and a forward spectrometer which measures the position, momentum and energy of the reaction fragments. The exclusive electromagnetic dissociation cross sections for decay channels having multiple nucleons in the final state have been measured which enables the selection of events produced in pure electromagnetic interactions. The measured cross sections agree well with previous measurements obtained for the removal of a few nucleons as well as with measurements on total charge removal cross sections from other experiments. The dependence of the integrated cross sections on the target charge Z{sub T} and the target mass AT confirms that for higher Z targets the excitation is largely electromagnetic. Direct measurements of the excitation energy for the electromagnetic dissociation of {sup 28}Si {yields} p+{sup 27}Al and {sup 28}Si {yields} n+{sup 27}Si have been obtained through a calculation of the invariant mass in kinematically, reconstructed events. The excitation energy spectrum for all targets peak near the isovector giant dipole resonance in {sup 28}Si. These distributions are well reproduced by combining the photon spectrum calculated using the Weizsaecker-Williams approximation with the experimental data on the photonuclear {sup 28}Si({sub {gamma},p}){sup 27}Al and {sup 28}Si({sub {gamma},n}){sup 27}Si. The possibilities of observing double giant dipole resonance excitations in {sup 28}Si have been investigated with cross section measurements as well as with excitation energy reconstruction.

Sonnadara, U.J.

1992-12-01T23:59:59.000Z

137

Electromagnetically Restrained Lithium Blanket APEX Interim Report November, 1999  

E-Print Network [OSTI]

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

California at Los Angeles, University of

138

Electromagnetic Inverse Problems Involving Distributions of Dielectric Mechanisms and Parameters  

E-Print Network [OSTI]

Electromagnetic Inverse Problems Involving Distributions of Dielectric Mechanisms and Parameters H University, Raleigh, NC 27695-8205 August 17, 2005 Abstract We consider electromagnetic interrogation, uniform, log-normal, and log-Bi-Gaussian distributions. Keywords: Electromagnetic interrogation

139

Regularity and approximation of systems arising in electromagnetic interrogation of  

E-Print Network [OSTI]

Regularity and approximation of systems arising in electromagnetic interrogation of dielectric describes the electromagnetic interrogation of dielectric materials. We address the well describing the electromagnetic in- terrogation of dielectric materials. Let E and H be the intensities

140

Narrow field electromagnetic sensor system and method  

DOE Patents [OSTI]

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.

McEwan, Thomas E. (Livermore, CA)

1996-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Space-time Curvature of Classical Electromagnetism  

E-Print Network [OSTI]

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.

R. W. M. Woodside

2004-10-08T23:59:59.000Z

142

Electromagnetic corrections to light hadron masses  

E-Print Network [OSTI]

At the precision reached in current lattice QCD calculations, electromagnetic effects are becoming numerically relevant. We will present preliminary results for electromagnetic corrections to light hadron masses, based on simulations in which a $\\mathrm{U}(1)$ degree of freedom is superimposed on $N_f=2+1$ QCD configurations from the BMW collaboration.

A. Portelli; S. Drr; Z. Fodor; J. Frison; C. Hoelbling; S. D. Katz; S. Krieg; T. Kurth; L. Lellouch; T. Lippert; K. K. Szab; A. Ramos

2011-01-12T23:59:59.000Z

143

Optimization Material Distribution methodology: Some electromagnetic examples  

E-Print Network [OSTI]

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

Paris-Sud XI, Université de

144

Dynamics of electromagnetic solitons in a relativistic plasma  

SciTech Connect (OSTI)

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.

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

145

An electromagnetic black hole made of metamaterials  

E-Print Network [OSTI]

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...

Cheng, Qiang

2009-01-01T23:59:59.000Z

146

Noninvasive valve monitor using alternating electromagnetic field  

DOE Patents [OSTI]

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.

Eissenberg, David M. (Oak Ridge, TN); Haynes, Howard D. (Knoxville, TN); Casada, Donald A. (Knoxville, TN)

1993-01-01T23:59:59.000Z

147

Electromagnetic field with constraints and Papapetrou equation  

E-Print Network [OSTI]

It is shown that geometric optical description of electromagnetic wave with account of its polarization in curved space-time can be obtained straightforwardly from the classical variational principle for electromagnetic field. For this end the entire functional space of electromagnetic fields must be reduced to its subspace of locally plane monochromatic waves. We have formulated the constraints under which the entire functional space of electromagnetic fields reduces to its subspace of locally plane monochromatic waves. These constraints introduce variables of another kind which specify a field of local frames associated to the wave and contain some congruence of null-curves. The Lagrangian for constrained electromagnetic field contains variables of two kinds, namely, a congruence of null-curves and the field itself. This yields two kinds of Euler-Lagrange equations. Equations of first kind are trivial due to the constraints imposed. Variation of the curves yields the Papapetrou equations for a classical massless particle with helicity 1.

Z. Ya. Turakulov; A. T. Muminov

2006-01-12T23:59:59.000Z

148

All-thin-film multilayered multiferroic structures with a slot-line for spin-electromagnetic wave devices  

SciTech Connect (OSTI)

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.

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); Lhderanta, E. [Department of Mathematics and Physics, Lappeenranta University of Technology, Lappeenranta 53850 Finland (Finland)

2014-03-03T23:59:59.000Z

149

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...

150

Electromagnetic Interference (EMI) Shielding of Single-Walled Carbon  

E-Print Network [OSTI]

Electromagnetic Interference (EMI) Shielding of Single-Walled Carbon Nanotube Epoxy Composites Ning (SWNT)-polymer composites have been fabricated to evaluate the electromagnetic interference (EMI

Gao, Hongjun

151

Project no. 516369 Electromagnetic compatibility between rolling stock and  

E-Print Network [OSTI]

to anything in that environment. Electromagnetic interference (EMI): Degradation of the performance compatibility EMI Electromagnetic interference ETSI European Telecommunications Standards Institute FM Frequency

Paris-Sud XI, Université de

152

Electromagnetic Interference in Wireless Communications: Behavioral-Level Simulation  

E-Print Network [OSTI]

Electromagnetic Interference in Wireless Communications: Behavioral-Level Simulation Approach in electromagnetic interference (EMI) modeling and simulation for modern and future wireless communication systems

Loyka, Sergey

153

The CLAS Forward Electromagnetic Calorimeter  

SciTech Connect (OSTI)

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.

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

154

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 49, NO. 3, AUGUST 2007 661 Novel Planar Electromagnetic Bandgap Structures  

E-Print Network [OSTI]

. A novel concept of using these EBG structures for electromagnetic interference reduction is also, the power/ground noise creates significant and new challenges for electromagnetic interference

Ramahi, Omar

155

Counting energy packets in the electromagnetic wave  

E-Print Network [OSTI]

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.

Stefan Popescu; Bernhard Rothenstein

2007-05-18T23:59:59.000Z

156

Spinors and pre-metric electromagnetism  

E-Print Network [OSTI]

The basic concepts of the formulation of Maxwellian electromagnetism in the absence of a Minkowski scalar product on spacetime are summarized, with particular emphasis on the way that the electromagnetic constitutive law on the space of bivectors over spacetime supplants the role of the Minkowski scalar product on spacetime itself. The complex geometry of the space of bivectors is summarized, with the intent of showing how an isomorphic copy of the Lorentz group appears in that context. The use of complex 3-spinors to represent electromagnetic fields is then discussed, as well as the expansion of scope that the more general complex projective geometry of the space of bivectors suggests.

David Delphenich

2005-12-22T23:59:59.000Z

157

On the Axioms of Topological Electromagnetism  

E-Print Network [OSTI]

The axioms of topological electromagnetism are refined by the introduction of the de Rham homology of k-vector fields on orientable manifolds and the use of Poincare duality in place of Hodge duality. The central problem of defining the electromagnetic constitutive law is elaborated upon in the linear and nonlinear cases. The manner by which the spacetime metric might follow from the constitutive law is examined in the linear case. The possibility that the intersection form of the spacetime manifold might play a role in defining a topological basis for the constitutive law is explored. The manner by which wave motion might follow from the electromagnetic structure is also discussed.

D. H. Delphenich

2003-12-14T23:59:59.000Z

158

Electromagnetic Studies of Mesons, Nucleons, and Nuclei  

SciTech Connect (OSTI)

Professor Baker was a faculty member at Hampton University in Hampton, Virginia, and, jointly, a Staff Physicist at Jefferson Lab in nearby Newport News from September 1989 to July 2006. The Department of Energy (DOE) funded the grant DE-FG02-97ER41035 Electromagnetic Studies of Mesons, Nucleons, and Nuclei, while Baker was in this joint appointment. Baker sent a closeout report on these activities to Hampton Universitys Sponsored Research Office some years ago, shortly after joining Yale University in 2006. In the period around 2001, the research grant with Baker as the Principal Investigator (PI) was put under the supervision of Professor Liguang Tang at Hampton University. Baker continued to pursue the research while in this join appointment, however the administrative responsibilities with the DOE and with Hampton University rested with Professor Tang after 2001, to my recollection. What is written in this document is from Bakers memory of the research activities, which he has not pursued since joining the Yale University faculty.

Baker, Oliver K.

2013-08-20T23:59:59.000Z

159

Electromagnetic Properties for Arbitrary Spin Particles: Part 1 $-$ Electromagnetic Current and Multipole Decomposition  

E-Print Network [OSTI]

In a set of two papers, we propose to study an old-standing problem, namely the electromagnetic interaction for particles of arbitrary spin. Based on the assumption that light-cone helicity at tree level and $Q^2=0$ should be conserved non-trivially by the electromagnetic interaction, we are able to derive \\emph{all} the natural electromagnetic moments for a pointlike particle of \\emph{any} spin. In this first paper, we propose a transparent decomposition of the electromagnetic current in terms of covariant vertex functions. We also define in a general way the electromagnetic multipole form factors, and show their relation with the electromagnetic moments. Finally, by considering the Breit frame, we relate the covariant vertex functions to multipole form factors.

Cdric Lorc

2009-01-27T23:59:59.000Z

160

Dynamic programming applied to electromagnetic satellite actuation  

E-Print Network [OSTI]

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 ...

Eslinger, Gregory John

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Advances in non-planar electromagnetic prototyping  

E-Print Network [OSTI]

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, ...

Ehrenberg, Isaac M

2013-01-01T23:59:59.000Z

162

Electrical wire insulation and electromagnetic coil  

DOE Patents [OSTI]

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.

Bich, George J. (Penn Hills, PA); Gupta, Tapan K. (Monroeville, PA)

1984-01-01T23:59:59.000Z

163

Electromagnetic Casimir piston in higher dimensional spacetimes  

E-Print Network [OSTI]

We consider the Casimir effect of the electromagnetic field in a higher dimensional spacetime of the form $M\\times \\mathcal{N}$, where $M$ is the 4-dimensional Minkowski spacetime and $\\mathcal{N}$ is an $n$-dimensional compact manifold. The Casimir force acting on a planar piston that can move freely inside a closed cylinder with the same cross section is investigated. Different combinations of perfectly conducting boundary conditions and infinitely permeable boundary conditions are imposed on the cylinder and the piston. It is verified that if the piston and the cylinder have the same boundary conditions, the piston is always going to be pulled towards the closer end of the cylinder. However, if the piston and the cylinder have different boundary conditions, the piston is always going to be pushed to the middle of the cylinder. By taking the limit where one end of the cylinder tends to infinity, one obtains the Casimir force acting between two parallel plates inside an infinitely long cylinder. The asymptotic behavior of this Casimir force in the high temperature regime and the low temperature regime are investigated for the case where the cross section of the cylinder in $M$ is large. It is found that if the separation between the plates is much smaller than the size of $\\mathcal{N}$, the leading term of the Casimir force is the same as the Casimir force on a pair of large parallel plates in the $(4+n)$-dimensional Minkowski spacetime. However, if the size of $\\mathcal{N}$ is much smaller than the separation between the plates, the leading term of the Casimir force is $1+h/2$ times the Casimir force on a pair of large parallel plates in the 4-dimensional Minkowski spacetime, where $h$ is the first Betti number of $\\mathcal{N}$. In the limit the manifold $\\mathcal{N}$ vanishes, one does not obtain the Casimir force in the 4-dimensional Minkowski spacetime if $h$ is nonzero.

L. P. Teo

2011-02-22T23:59:59.000Z

164

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Neil V. Budko; Alexander B. Samokhin

2006-06-15T23:59:59.000Z

165

Singular Modes of the Electromagnetic Field  

E-Print Network [OSTI]

We show that the mode corresponding to the point of essential spectrum of the electromagnetic scattering operator is a vector-valued distribution representing the square root of the three-dimensional Dirac's delta function. An explicit expression for this singular mode in terms of the Weyl sequence is provided and analyzed. An essential resonance thus leads to a perfect localization (confinement) of the electromagnetic field, which in practice, however, may result in complete absorption.

Budko, N V; Budko, Neil V.; Samokhin, Alexander B.

2006-01-01T23:59:59.000Z

166

Characterization of electromagnetic transients in power substations  

E-Print Network [OSTI]

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...

Goers, William Chester

1980-01-01T23:59:59.000Z

167

Electromagnetic Beams Overpass the Black Hole Horizon  

E-Print Network [OSTI]

We show that the electromagnetic excitations of the Kerr black hole have very strong back reaction on metric. In particular, the electromagnetic excitations aligned with the Kerr congruence form the light-like beams which overcome horizon, forming the holes in it, which allows matter to escape interior. So, there is no information lost inside the black hole. This effect is based exclusively on the analyticity of the algebraically special solutions.

Alexander Burinskii

2008-06-16T23:59:59.000Z

168

Electromagnetic Corrections in Staggered Chiral Perturbation Theory  

E-Print Network [OSTI]

To reduce errors in light-quark mass determinations, it is now necessary to consider electromagnetic contributions to light-meson masses. Calculations using staggered quarks and quenched photons are currently underway. Suitably-extended chiral perturbation theory is necessary to extrapolate the lattice data to the physical limit. Here we give (preliminary) results for light-meson masses using staggered chiral perturbation theory including electromagnetism, and discuss the extent to which quenched-photon simulations can improve quark-mass calculations.

C. Bernard; E. D. Freeland

2010-11-17T23:59:59.000Z

169

Electromagnetic and spin polarisabilities in lattice QCD  

E-Print Network [OSTI]

We discuss the extraction of the electromagnetic and spin polarisabilities of nucleons from lattice QCD. We show that the external field method can be used to measure all the electromagnetic and spin polarisabilities including those of charged particles. We then turn to the extrapolations required to connect such calculations to experiment in the context of chiral perturbation theory, finding a strong dependence on the lattice volume and quark masses.

W. Detmold; B. C. Tiburzi; A. Walker-Loud

2006-10-02T23:59:59.000Z

170

Elec Eng 2FH3 Electromagnetics I COURSE NUMBER & TITLE: Elec Eng 2FH3 Electromagnetics I  

E-Print Network [OSTI]

Elec Eng 2FH3 ­ Electromagnetics I COURSE NUMBER & TITLE: Elec Eng 2FH3 ­ Electromagnetics I field 6. Inductance 7. Faraday's law CALENDAR DESCRIPTION: Electromagnetics Part I is an introduction into engineering electromagnetics. It covers the mathematical foundations such as selected topics of vector

Haykin, Simon

171

Terahertz electromagnetic wave generation and amplification by an electron beam in the elliptical plasma waveguides with dielectric rod  

SciTech Connect (OSTI)

The propagation of electromagnetic waves in an elliptical plasma waveguide including strongly magnetized plasma column and a dielectric rod is investigated. The dispersion relation of guided hybrid electromagnetic waves is obtained. Excitation of the waves by a thin annular relativistic elliptical electron beam will be studied. The time growth rate of electromagnetic waves is obtained. The effects of relative permittivity constant of dielectric rod, radius of dielectric rod, accelerating voltage, and current density of the annular elliptical beam on the growth rate and the frequency spectra are numerically presented.

Rahmani, Z., E-mail: z.rahmani@kashanu.ac.ir; Jazi, B. [Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Heidari-Semiromi, E. [Department of Condense Matter, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

2014-09-15T23:59:59.000Z

172

Effects of Electromagnetic Field on the Dynamics of Bianchi type $VI_0$ Universe with Anisotropic Dark Energy  

E-Print Network [OSTI]

Spatially homogeneous and anisotropic Bianchi type $VI_0$ cosmological models with cosmological constant are investigated in the presence of anisotropic dark energy. We examine the effects of electromagnetic field on the dynamics of the universe and anisotropic behavior of dark energy. The law of variation of the mean Hubble parameter is used to find exact solutions of the Einstein field equations. We find that electromagnetic field promotes anisotropic behavior of dark energy which becomes isotropic for future evolution. It is concluded that the isotropic behavior of the universe model is seen even in the presence of electromagnetic field and anisotropic fluid.

M. Sharif; M. Zubair

2010-08-04T23:59:59.000Z

173

Innovative Electromagnetic Sensors for Pipeline Crawlers  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. Battelle is in the final year on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The second semiannual report on this project reported on experimental and modeling results. The results showed that the rotating system was more adaptable to pipeline inspection and therefore only this system will be carried into the second year of the sensor development. In the third reporting period, the rotating system inspection was further developed. Since this is a new inspection modality without published fundamentals to build upon, basic analytical and experimental investigations were performed. A closed form equation for designing rotating exciters and positioning sensors was derived from fundamental principles. Also signal processing methods were investigated for detection and assessment of pipeline anomalies. A lock in amplifier approach was chosen as the method for detecting the signals. Finally, mechanical implementations for passing tight restrictions such as plug valves were investigated. This inspection concept is new and unique; a United States patent application has been submitted. In this reporting period, a general design of the rotating permanent magnet inspection system is presented. The rotating permanent magnet inspection system is feasible for pipes ranging in diameter from 8 to 18 inches using a two pole configuration. Experimental results and theoretical calculations provide the basis for selection of the critical design parameters. The parameters include a significant magnet to pipe separation that will facilitate the passage of pipeline features. With the basic values of critical components established, the next step is a detailed mechanical design of a pipeline ready inspection system.

J. Bruce Nestleroth

2006-05-04T23:59:59.000Z

174

INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. The Applied Energy Systems Group at Battelle is in the second year of work on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The second semiannual report on this project reported on experimental and modeling results. The results showed that the rotating system was more adaptable to pipeline inspection and therefore only this system will be carried into the second year of the sensor development. In this third reporting period, the rotating system inspection was further developed. Since this is a new inspection modality without published fundamentals to build upon, basic analytical and experimental investigations were performed. A closed form equation for designing rotating exciters and positioning sensors was derived from fundamental principles. Also signal processing methods were investigated for detection and assessment of pipeline anomalies. A lock in amplifier approach was chosen as the method for detecting the signals. Finally, mechanical implementations for passing tight restrictions such as plug valves were investigated. This inspection concept is new and unique; a United States patent application has been submitted.

J. Bruce Nestleroth; Richard J. Davis

2005-05-23T23:59:59.000Z

175

INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. Battelle has completed the second year of work on a projected three-year development effort. In the first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. The second inspection methodology is based on rotating permanent magnets. The rotating exciter unit produces strong eddy currents in the pipe wall. At distances of a pipe diameter or more from the rotating exciter, the currents flow circumferentially. These circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall. The second semiannual report on this project reported on experimental and modeling results. The results showed that the rotating system was more adaptable to pipeline inspection and therefore only this system will be carried into the second year of the sensor development. In the third reporting period, the rotating system inspection was further developed. Since this is a new inspection modality without published fundamentals to build upon, basic analytical and experimental investigations were performed. A closed form equation for designing rotating exciters and positioning sensors was derived from fundamental principles. Also signal processing methods were investigated for detection and assessment of pipeline anomalies. A lock in amplifier approach was chosen as the method for detecting the signals. Finally, mechanical implementations for passing tight restrictions such as plug valves were investigated. This inspection concept is new and unique; a United States patent application has been submitted. In this fourth reporting period, the rotating system inspection was further developed. A multichannel real-time data recorder system was implemented and fundamental experiments were conducted to provide data to aid in the design of the rotating magnetizer system. An unexpected but beneficial result was achieved when examining the separation between the rotating magnet and the pipe wall; separations of over an inch could be tolerated. Essentially no change in signal from corrosion anomalies could be detected for separations up to 1.35 inches. The results presented in this report will be used to achieve the next deliverable, designs of components of the rotating inspection system that will function with inspection crawlers in a pipeline environment.

J. Bruce Nestleroth

2005-11-30T23:59:59.000Z

176

Name of the Presentation Fundamental Properties of Electromagnetic RadiationFundamental Properties of Electromagnetic Radiation  

E-Print Network [OSTI]

a continuous spectrum of energy from gamma rays to radio waves. The visible portion of the spectrum may to radio waves. The visible portion of the spectrum may be measured using wavelength (measured between the Sun and the Earth. Electromagnetic Spectrum Electromagnetic Spectrum The Sun produces

177

Electrical, electromagnetic and structural characteristics of carbon nanotube-polymer nanocomposites  

E-Print Network [OSTI]

Composites for Electromagnetic Interference Shielding. NanoY. Ma, et al. Electromagnetic Interference (EMI) Shieldingof Bonn). Chung DDL. Electromagnetic interference shielding

Park, Sung-Hoon

2009-01-01T23:59:59.000Z

178

Discussion on the Mechanism of Electromigration from the Perspective of Electromagnetism  

E-Print Network [OSTI]

from the Perspective of Electromagnetism PENG ZHOU 1,3 andthe perspective of electromagnetism, rather than from thecharge, electromigration, electromagnetism INTRODUCTION

Zhou, Peng; Johnson, William C.

2010-01-01T23:59:59.000Z

179

MEASUREMENT AND ANALYSIS OF ELECTROMAGNETIC FIELDS FROM TRAMS, TRAINS AND HYBRID CARS  

E-Print Network [OSTI]

MEASUREMENT AND ANALYSIS OF ELECTROMAGNETIC FIELDS FROM TRAMS, TRAINS AND HYBRID CARS Malka N of electric and magnetic fields emitted from Australian trams, trains and hybrid cars were investigated (EMFs) has arisen. People using trains, trams and hybrid cars are exposed to higher alternating

Halgamuge, Malka N.

180

Self-generation and management of spin-electromagnetic wave solitons and chaos  

SciTech Connect (OSTI)

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.

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

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Response of radio frequency superconducting quantum interference devices to electromagnetic interference  

SciTech Connect (OSTI)

A number of applications of high-temperature superconductor radio frequency superconducting quantum interference devices (rf SQUIDs) require a certain immunity of these sensors against electromagnetic interference (EMI). We have investigated effects of electromagnetic radiation in the high-frequency and ultrahigh-frequency range on various types of rf SQUIDs. It has been found that EMI of sufficient field strength reduces the voltage versus flux transfer function, and thus increases the flux noise of the SQUIDs. SQUIDs with a wire wound tank circuit coil have been found to be more sensitive to EMI than SQUIDs integrated into a superconducting microstrip resonator. {copyright} {ital 1995} {ital American} {ital Institute} {ital of} {ital Physics}.

Mueck, M.; Dechert, J.; Gail, J.; Kreutzbruck, M.; Schoene, S.; Weidl, R. [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)] [Institut fuer Angewandte Physik, Justus-Liebig-Universitaet Giessen, Heinrich-Buff-Ring 16, 35392 Giessen (Germany)

1995-09-01T23:59:59.000Z

182

Electromagnetic wave propagation in a random distribution of C{sub 60} molecules  

SciTech Connect (OSTI)

Propagation of electromagnetic waves in a random distribution of C{sub 60} molecules are investigated, within the framework of the classical electrodynamics. Electronic excitations over the each C{sub 60} molecule surface are modeled by a spherical layer of electron gas represented by two interacting fluids, which takes into account the different nature of the ? and ? electrons. It is found that the present medium supports four modes of electromagnetic waves, where they can be divided into two groups: one group with shorter wavelength than the light waves of the same frequency and the other with longer wavelength than the free-space radiation.

Moradi, Afshin, E-mail: a.moradi@kut.ac.ir [Department of Engineering Physics, Kermanshah University of Technology, Kermanshah, Iran and Department of Nano Sciences, Institute for Studies in Theoretical Physics and Mathematics (IPM), Tehran (Iran, Islamic Republic of)

2014-10-15T23:59:59.000Z

183

Self-focusing of intense high frequency electromagnetic waves in a collisional magnetoactive plasma  

SciTech Connect (OSTI)

The self-focusing of an intense electromagnetic beam in a collisional magnetoactive plasma has been investigated by the perturbation method. Considering the relativistic and ponderomotive nonlinearities and the first three terms of perturbation expansion for the electron density and velocity, the nonlinear wave equation is obtained. This wave equation is solved by applying the source dependent expansion method and the evolution of electromagnetic beam spot-size is discussed. It is shown that the laser spot-size decreases with increasing the collision frequency and external magnetic field strength.

Niknam, A. R.; Hashemzadeh, M. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Evin, Tehran (Iran, Islamic Republic of); Aliakbari, A.; Majedi, S. [Physics Department, Faculty of Science, Tafresh University, Tafresh (Iran, Islamic Republic of); Haji Mirzaei, F. [Physics Department, Islamic Azad University, Arak Branch, Arak (Iran, Islamic Republic of)

2011-11-15T23:59:59.000Z

184

Complex geometry and pre-metric electromagnetism  

E-Print Network [OSTI]

The intimate link between complex geometry and the problem of the pre-metric formulation of electromagnetism is explored. In particular, the relationship between 3+1 decompositions of R4 and the decompositions of the vector space of bivectors over R4 into real and imaginary subspaces relative to a choice of complex structure is emphasized. The role of the various scalar products on the space of bivectors that are defined in terms of a volume element on R4 and a complex structure on the space of bivectors that makes it C-linear isomorphic to C3 is discussed in the context of formulation of a theory of electromagnetism in which the Lorentzian metric on spacetime follows as a consequence of the existence of electromagnetic waves, not a prior assumption.

D. H. Delphenich

2004-12-10T23:59:59.000Z

185

Electromagnetic Radiations as a Fluid Flow  

E-Print Network [OSTI]

We combine Maxwell's equations with Eulers's equation, related to a velocity field of an immaterial fluid, where the density of mass is replaced by a charge density. We come out with a differential system able to describe a relevant quantity of electromagnetic phenomena, ranging from classical dipole waves to solitary wave-packets with compact support. The clue is the construction of an energy tensor summing up both the electromagnetic stress and a suitable mass tensor. With this right-hand side, explicit solutions of the full Einstein's equation are computed for a wide class of wave phenomena. Since our electromagnetic waves may behave and interact exactly as a material fluid, they can create vortex structures. We then explicitly analyze some vortex ring configurations and examine the possibility to build a model for the electron.

Daniele Funaro

2009-11-25T23:59:59.000Z

186

Merging electromagnetism with space-time metric  

E-Print Network [OSTI]

In the present work, it is shown that the electromagnetism may be directly associated to the four-dimensional space-time geometry. The starting point is an analysis of the geodesic equation of general relativity where it is verified that it contains implicitly the effects of the Coulomb and the Lorentz forces. Consequently, some components of the metric tensor are identified with the components of the four-vector electromagnetic potential. Then, it is constructed a low-field equation for the electromagnetism in the same structure of the Einstein field equations for the gravitation, relating the curvature of space-time to sources of charge and current density. In this framework, all the Maxwell equations are implicit. A proof of consistency with the framework of quantum mechanics is shown.

C. A. Duarte

2014-03-10T23:59:59.000Z

187

Gravitation and electromagnetism in theory of a unified four-vector field  

E-Print Network [OSTI]

A four-vector field in flat space-time, satisfying a gauge-invariant set of second-order differential equations, is considered as a unified field. The model variational principle corresponds to the general covariance idea and gives rise to nonlinear Born-Infeld electrodynamics. Thus the four-vector field is considered as an electromagnetic potential. It is suggested that space-localized (particle) solutions of the nonlinear field model correspond to material particles. Electromagnetic and gravitational interactions between field particles appear naturally when a many-particle solution is investigated with the help of a perturbation method. The electromagnetic interaction appears in the first order in the small field of distant particles. In the second order, there is an effective Riemannian space induced by the field of distant particles. This Riemannian space can be connected with gravitation.

Alexander A. Chernitskii

2006-09-28T23:59:59.000Z

188

Electromagnetic Waves in the De Sitter Space  

E-Print Network [OSTI]

5-Dimensional wave equation for a massive particle of spin 1 in the background of de Sitter space-time model is solved in static coordinates. The spherical 5-dimensional vectors $A_{a}, a= 1,...,5$ of three types, $j,j+1, j-1$ are constructed. In massless case they give electromagnetic wave solutions, obeying the Lorentz condition. 5-form of equations in massless case is used to produce recipe to build electromagnetic wave solutions of the types $\\Pi, E,M$; the first is trivial and can be removed by a gauge ransformation. The recipe is specified to produce spherical $\\Pi, E, M$ solutions in static coordinates.

V. S. Otchik; V. M. Red'kov

2010-01-24T23:59:59.000Z

189

Scanning evanescent electro-magnetic microscope  

DOE Patents [OSTI]

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.

Xiang, Xiao-Dong (Alameda, CA); Gao, Chen (Alameda, CA)

2001-01-01T23:59:59.000Z

190

Phenomenology of the Deuteron Electromagnetic Form Factors  

E-Print Network [OSTI]

A rigorous extraction of the deuteron charge form factors from tensor polarization data in elastic electron-deuteron scattering, at given values of the 4-momentum transfer, is presented. Then the world data for elastic electron-deuteron scattering is used to parameterize, in three different ways, the three electromagnetic form factors of the deuteron in the 4-momentum transfer range 0-7 fm^-1. This procedure is made possible with the advent of recent polarization measurements. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic structure. They can be used to remove ambiguities in the form factors extraction from future polarization data.

TheJLAB t20 collaboration; D. Abbott

2000-02-25T23:59:59.000Z

191

Duality in Off-Shell Electromagnetism  

E-Print Network [OSTI]

In this paper, we examine the Dirac monopole in the framework of Off-Shell Electromagnetism, the five dimensional U(1) gauge theory associated with Stueckelberg-Schrodinger relativistic quantum theory. After reviewing the Dirac model in four dimensions, we show that the structure of the five dimensional theory prevents a natural generalization of the Dirac monopole, since the theory is not symmetric under duality transformations. It is shown that the duality symmetry can be restored by generalizing the electromagnetic field strength to an element of a Clifford algebra. Nevertheless, the generalized framework does not permit us to recover the phenomenological (or conventional) absence of magnetic monopoles.

Martin Land

2006-03-21T23:59:59.000Z

192

Electromagnetic waves, gravitational coupling and duality analysis  

E-Print Network [OSTI]

In this letter we introduce a particular solution for parallel electric and magnetic fields, in a gravitational background, which satisfy free-wave equations and the phenomenology suggested by astrophysical plasma physics. These free-wave equations are computed such that the electric field does not induce the magnetic field and vice-versa. In a gravitational field, we analyze the Maxwell equations and the corresponding electromagnetic waves. A continuity equation is presented. A commutative and noncommutative analysis of the electromagnetic duality is described.

E. M. C. Abreu; C. Pinheiro; S. A. Diniz; F. C. Khanna

2005-10-27T23:59:59.000Z

193

Electromagnetic Observables in Few-Nucleon Systems  

E-Print Network [OSTI]

The electromagnetic probe is a very valuable tool to study the dynamics of few nucleons. It can be very helpful in shedding light on the not yet fully understood three-nucleon forces. We present an update on the theoretical studies of electromagnetic induced reactions, such as photo-disintegration and electron scattering off 4He. We will show that they potentially represent a tool to discriminate among three-nucleon forces. Then, we will discuss the charge radius and the nuclear electric polarizability of the 6He halo nucleus.

Sonia Bacca

2012-10-10T23:59:59.000Z

194

Electromagnetic continuous casting project: Final report  

SciTech Connect (OSTI)

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.

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

195

Dr. S. Cruz-Pol, INEL 4152-Electromagnetics  

E-Print Network [OSTI]

field density [VF/m2] ?H = magnetic field intensity, [A/m] ?B = magnetic field density, [Teslas] Take JdlH Cruz-Pol, Electromagnetics UPRM Electromagnetics ? This is the principle of motors, hydro

Cruz-Pol, Sandra L.

196

On the gravitational fields created by the electromagnetic waves  

E-Print Network [OSTI]

We show that the Maxwell equations describing an electromagnetic wave are a mathematical consequence of the Einstein equations for the same wave. This fact is significant for the problem of the Einsteinian metrics corresponding to the electromagnetic waves.

A. Loinger; T. Marsico

2011-06-11T23:59:59.000Z

197

College of Engineering Electromagnetically Enhanced Hydrocyclone for Magnetite Separation during  

E-Print Network [OSTI]

designed the cyclone; a safer technology aimed at replacing the drum separators. The prototy er increase Electromagnetically Enhanced Hydrocyclone for Magnetite Separation during cyclone; a safer technology aimedPENNSTATE College of Engineering Electromagnetically Enhanced Hydrocyclone for Magnetite Separation

Demirel, Melik C.

198

Electromagnetic Light in Medium of Polarized Atoms $^3$He  

E-Print Network [OSTI]

First, it is predicted that polarized atoms $^3$He increase a value of speed electromagnetic waves. This reasoning implies that the velocity of electromagnetic waves into gas consisting of polarized atoms $^3$He is rather than one in vacuum.

V. N. Minasyan

2009-04-01T23:59:59.000Z

199

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...

200

E-Print Network 3.0 - axisymmetric electromagnetic resonators...  

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

-Lab Northwest Electromagnetics & Acoustics Research Outline Introduction to Terahertz ... Source: La Rosa, Andres H. - Department of Physics, Portland State...

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Influence of Absorbers on the Electromagnetic Radiation  

E-Print Network [OSTI]

The phenomenon of the electromagnetic absorption by arbitrarily distributed discrete absorbers is analyzed from the photon point of view. It is shown that apart from the decrease in the intensity of the signal the net effect of absorption includes a relative increase in the photon bunching.

Budko, Neil V

2007-01-01T23:59:59.000Z

202

Influence of Absorbers on the Electromagnetic Radiation  

E-Print Network [OSTI]

The phenomenon of the electromagnetic absorption by arbitrarily distributed discrete absorbers is analyzed from the photon point of view. It is shown that apart from the decrease in the intensity of the signal the net effect of absorption includes a relative increase in the photon bunching.

Neil V. Budko

2007-12-05T23:59:59.000Z

203

FMM Code Libraries for Computational Electromagnetics  

E-Print Network [OSTI]

Max Optics, Inc. #12;MadMax Optics 2 · Stealth · Electromagnetic interference · Antennas on complex platforms ­ Closed and open surfaces, complex materials · Fast, Direct Solvers for Ill-Conditioned Problems ­ handle isotropic materials with closed surfaces ­ Open surfaces still active area of research · Geometric

Maryland at College Park, University of

204

Structural composites with integrated electromagnetic functionality  

E-Print Network [OSTI]

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

Nemat-Nasser, Sia

205

Electromagnetic Composites at the Compton Scale  

E-Print Network [OSTI]

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.

Frederick J. Mayer; John R. Reitz

2011-09-10T23:59:59.000Z

206

Line geometry and electromagnetism I: basic structures  

E-Print Network [OSTI]

Some key notions of line geometry are recalled, along with their application to mechanics. It is then shown that most of the basic structures that one introduces in the pre-metric formulation of electromagnetism can be interpreted directly in terms of corresponding concepts in line geometry. The results are summarized in a table.

D. H. Delphenich

2013-09-11T23:59:59.000Z

207

Electromagnetic Siegert states for periodic dielectric structures  

E-Print Network [OSTI]

The formalism of Siegert states to describe the resonant scattering in quantum theory is extended to the resonant scattering of electromagnetic waves on periodic dielectric arrays. The excitation of electromagnetic Siegert states by an incident wave packet and their decay is studied. The formalism is applied to develop a theory of coupled electromagnetic resonances arising in the electromagnetic scattering problem for two such arrays separated by a distance 2h (or, generally, when the physical properties of the scattering array depend on a real coupling parameter h). Analytic properties of Siegert states as functions of the coupling parameter h are established by the Regular Perturbation Theorem which is an extension the Kato-Rellich theorem to the present case. By means of this theorem, it is proved that if the scattering structure admits a bound state in the radiation continuum at a certain value of the coupling parameter h, then there always exist regions within the structure in which the near field can be amplified as much as desired by adjusting the value of h. This establishes a rather general mechanism to control and amplify optical nonlinear effects in periodically structured planar structures possessing a nonlinear dielectric susceptibility.

Friends R. Ndangali; Sergei V. Shabanov

2011-08-09T23:59:59.000Z

208

Decomposition of Electromagnetic Q and P Media  

E-Print Network [OSTI]

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.

Lindell, I V

2015-01-01T23:59:59.000Z

209

Electromagnetic Wellbore Heating Ibrahim Agyemang1  

E-Print Network [OSTI]

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

Bohun, C. Sean

210

Electromagnetic characterization of PCB cards for mobile phones  

E-Print Network [OSTI]

Electromagnetic characterization of PCB cards for mobile phones Ali Jazzar(*), Edith Clavel state, more the price linked to the EMC (Electromagnetic Compatibility) requirements is important .Thus the electromagnetic perturbations inside and outside the structure. The required CAD tool to achieve this modeling

Boyer, Edmond

211

Electromagnetics, 26:335, 2006 Copyright Taylor & Francis Group, LLC  

E-Print Network [OSTI]

Electromagnetics, 26:3­35, 2006 Copyright © Taylor & Francis Group, LLC ISSN: 0272-6343 print/1532 the statistical properties of the impedance (Z) and scattering (S) matrices of open electromagnetic cavities. Introduction The problem of the coupling of electromagnetic radiation in and out of structures is a general one

Anlage, Steven

212

Electromagnetic measurements of duodenal digesta flow in cannulated sheep  

E-Print Network [OSTI]

Electromagnetic measurements of duodenal digesta flow in cannulated sheep C. PONCET, M. IVAN M of duodenal digesta flow were made in sheep implanted with an electromagnetic flowmeter probe on the ascending to frequent oscillation of the digesta. It was concluded that accurate quantitative electromagnetic

Paris-Sud XI, Université de

213

Hydrodynamic construction of the electromagnetic field  

E-Print Network [OSTI]

We present an alternative Eulerian hydrodynamic model for the electromagnetic field in which the discrete vector indices in Maxwell\\s equations are replaced by continuous angular freedoms, and develop the corresponding Lagrangian picture in which the fluid particles have rotational and translational freedoms. This enables us to extend to the electromagnetic field the exact method of state construction proposed previously for spin 0 systems, in which the time-dependent wavefunction is computed from a single-valued continuum of deterministic trajectories where two spacetime points are linked by at most a single orbit. The deduction of Maxwell\\s equations from continuum mechanics is achieved by generalizing the spin 0 theory to a general Riemannian manifold from which the electromagnetic construction is extracted as a special case. In particular, the flat-space Maxwell equations are represented as a curved-space Schr\\"odinger equation for a massive system. The Lorentz covariance of the Eulerian field theory is obtained from the non-covariant Lagrangian-coordinate model as a kind of collective effect. The method makes manifest the electromagnetic analogue of the quantum potential that is tacit in Maxwell\\s equations. This implies a novel definition of the \\classical limit\\ of Maxwell\\s equations that differs from geometrical optics. It is shown that Maxwell\\s equations may be obtained by canonical quantization of the classical model. Using the classical trajectories a novel expression is derived for the propagator of the electromagnetic field in the Eulerian picture. The trajectory and propagator methods of solution are illustrated for the case of a light wave.

Peter Holland

2014-10-03T23:59:59.000Z

214

Numerical Methods of Computational Electromagnetics for Complex Inhomogeneous Systems  

SciTech Connect (OSTI)

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.

Cai, Wei

2014-05-15T23:59:59.000Z

215

Ultrarelativistic electron states in a general background electromagnetic field  

E-Print Network [OSTI]

The feasibility of obtaining exact analytical results in the realm of QED in the presence of a background electromagnetic field is almost exclusively limited to a few tractable cases, where the Dirac equation in the corresponding background field can be solved analytically. This circumstance has restricted, in particular, the theoretical analysis of QED processes in intense laser fields to within the plane-wave approximation even at those high intensities, achievable experimentally only by tightly focusing the laser energy in space. Here, within the Wentzel-Kramers-Brillouin (WKB) or eikonal approximation, we construct analytically single-particle electron states in the presence of a background electromagnetic field of general space-time structure in the realistic assumption that the initial energy of the electron is the largest dynamical energy scale in the problem. The relatively compact expression of these states opens, in particular, the possibility of investigating analytically strong-field QED processes in the presence of spatially focused laser beams, which is of particular relevance in view of the upcoming experimental campaigns in this field.

A. Di Piazza

2014-07-27T23:59:59.000Z

216

A strong permanent magnet-assisted electromagnetic undulator  

DOE Patents [OSTI]

This invention discloses an improved undulator comprising a plurality of electromagnet poles located along opposite sides of a particle beam axis with alternate north and south poles on each side of the beam to cause the beam to wiggle or undulate as it travels generally along the beam axis and permanent magnets spaced adjacent the electromagnetic poles on each side of the axis of said particle beam in an orientation sufficient to reduce the saturation of the electromagnet poles whereby the field strength of the electromagnet poles can be increased beyond the normal saturation levels of the electromagnetic poles. 4 figs.

Halbach, K.

1987-01-30T23:59:59.000Z

217

Nanofocusing of mid-infrared electromagnetic waves on graphene monolayer  

SciTech Connect (OSTI)

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 510{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.

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

218

Instability-driven electromagnetic fields in coronal plasmas  

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

Filamentary electromagnetic fields previously observed in the coronae of laser-driven spherical targets [F. H. S#2;eguin et al., Phys. Plasma. 19, 012701 (2012)] have been further investigated in laser irradiated plastic foils. Face-on proton-radiography provides an axial view of these filaments and shows coherent cellular structure regardless of initial foil-surface conditions. The observed cellular fields are shown to have an approximately constant scale size of #2;210 lm throughout the plasma evolution. A discussion of possible field-generation mechanisms is provided and it is demonstrated that the likely source of the cellular field structure is the magnetothermal instability. Using predicted temperature and density profiles, the fastest growing modes of this instability were found to be slowly varying in time and consistent with the observed cellular size.

Manuel, M. J.-E.; Li, C. K.; Seguin, F. H.; Sinenian, N.; Frenje, J. A.; Casey, D. T.; Petrasso, R. D.; Hager, J. D.; Betti, R.; Hu, S. X.; Delettrez, J.; Meyerhofer, D. D.

2013-01-01T23:59:59.000Z

219

Electromagnetic Scattering by Spheres of Topological Insulators  

E-Print Network [OSTI]

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.

Ge, Lixin; Zi, Jian

2015-01-01T23:59:59.000Z

220

A Connection between Gravitation and Electromagnetism  

E-Print Network [OSTI]

It is argued that there is a connection between the fundamental forces of electromagnetism and gravitation. This connection occurs because of: 1) the fundamental significance of the finite and invariant velocity of light in inertial reference frames in the special theory, and 2) the reliance of the general theory of relativity upon the special theory of relativity locally in spacetime. The connection between the fundamental forces of electromagnetism and gravitation follows immediately from these two points. A brief review is provided of: 1) the role of the finite and invariant velocity of light in inertial reference frames in the special theory, and 2) certain fundamental concepts of the general theory, including its reliance on the special theory locally.

D. M. Snyder

2000-02-16T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Electromagnetic or other directed energy pulse launcher  

DOE Patents [OSTI]

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.

Ziolkowski, Richard W. (Livermore, CA)

1990-01-01T23:59:59.000Z

222

Electromagnetic Dark Energy and Gravitoelectrodynamics of Superconductors  

E-Print Network [OSTI]

It is shown that Beck and Mackey electromagnetic model of dark energy in superconductors can account for the non-classical inertial properties of superconductors, which have been conjectured by the author to explain the Cooper pair's mass excess reported by Cabrera and Tate. A new Einstein-Planck regime for gravitation in condensed matter is proposed as a natural scale to host the gravitoelectrodynamic properties of superconductors.

Clovis Jacinto de Matos

2007-10-29T23:59:59.000Z

223

Electromagnetic couplings of elementary vector particles  

E-Print Network [OSTI]

On the basis of the three fundamental principles of (i) Poincar\\'{e} symmetry of space time, (ii) electromagnetic gauge symmetry, and (iii) unitarity, we construct an universal Lagrangian for the electromagnetic interactions of elementary vector particles, i.e., massive spin-1 particles transforming in the /1/2,1/2) representation space of the Homogeneous Lorentz Group (HLG). We make the point that the first two symmetries alone do not fix the electromagnetic couplings uniquely but solely prescribe a general Lagrangian depending on two free parameters, here denoted by \\xi and g. The first one defines the electric-dipole and the magnetic-quadrupole moments of the vector particle, while the second determines its magnetic-dipole and electric-quadrupole moments. In order to fix the parameters one needs an additional physical input suited for the implementation of the third principle. As such, one chooses Compton scattering off a vector target and requires the cross section to respect the unitarity bounds in the high energy limit. In result, we obtain the universal g=2, and \\xi=0 values which completely characterize the electromagnetic couplings of the considered elementary vector field at tree level. The nature of this vector particle, Abelian versus non-Abelian, does not affect this structure. Merely, a partition of the g=2 value into non-Abelian, g_{na}, and Abelian, g_{a}=2-g_{na}, contributions occurs for non-Abelian fields with the size of g_{na} being determined by the specific non-Abelian group appearing in the theory of interest, be it the Standard Model or any other theory.

M. Napsuciale; S. Rodriguez; E. G. Delgado-Acosta; M. Kirchbach

2007-11-27T23:59:59.000Z

224

Velocity damper for electromagnetically levitated materials  

DOE Patents [OSTI]

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material is disclosed. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation. 1 fig.

Fox, R.J.

1994-06-07T23:59:59.000Z

225

Paternal occupational exposure to electromagnetic fields and neuroblastoma in offspring  

SciTech Connect (OSTI)

Investigators in Texas have reported an association between paternal employment in jobs linked with exposure to electromagnetic fields and risk of neuroblastoma in offspring. In an attempt to replicate this finding, the authors conducted a case-control study in Ohio. A total of 101 incident cases of neuroblastoma were identified through the Columbus (Ohio) Children's Hospital Tumor Registry. All cases were born sometime during the period 1942-1967. From a statewide roster of birth certificates, four controls were selected for each case, with individual matching on the case's year of birth, race, and sex, and the mother's county of residence at the time of the (index) child's birth. Multiple definitions were employed to infer the potential for paternal occupational exposure to electromagnetic fields from the industry/occupation statements on the birth certificates. Case-control comparisons revealed adjusted odds ratios ranging in magnitude from 0.5 to 1.9. For two of the exposure definitions employed--both of which are similar to one used by the Texas investigators--the corresponding odds ratios were modestly elevated (odds ratios = 1.6 and 1.9). Notably, the magnitude of these odds ratios is not inconsistent with the Texas findings, where the exposure definition referred to yielded an odds ratio of 2.1. Because the point estimates in this study are imprecise, and because the biologic plausibility of the association is uncertain, the results reported here must be interpreted cautiously. However, the apparent consistency between two independent studies suggests that future evaluation of the association is warranted.

Wilkins, J.R. 3d.; Hundley, V.D. (Ohio State Univ., Columbus (USA))

1990-06-01T23:59:59.000Z

226

The electromagnetic model of Gamma Ray Bursts  

E-Print Network [OSTI]

I describe electromagnetic model of gamma ray bursts and contrast its main properties and predictions with hydrodynamic fireball model and its magnetohydrodynamical extension. The electromagnetic model assumes that rotational energy of a relativistic, stellar-mass central source (black-hole--accretion disk system or fast rotating neutron star) is converted into magnetic energy through unipolar dynamo mechanism, propagated to large distances in a form of relativistic, subsonic, Poynting flux-dominated wind and is dissipated directly into emitting particles through current-driven instabilities. Thus, there is no conversion back and forth between internal and bulk energies as in the case of fireball model. Collimating effects of magnetic hoop stresses lead to strongly non-spherical expansion and formation of jets. Long and short GRBs may develop in a qualitatively similar way, except that in case of long bursts ejecta expansion has a relatively short, non-relativistic, strongly dissipative stage inside the star. Electromagnetic and fireball models (as well as strongly and weakly magnetized fireballs) lead to different early afterglow dynamics, before deceleration time. Finally, I discuss the models in view of latest observational data in the Swift era.

Maxim Lyutikov

2005-12-13T23:59:59.000Z

227

Division of the momentum of electromagnetic waves in linear media into electromagnetic and material parts  

E-Print Network [OSTI]

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.

Pablo L. Saldanha

2010-02-04T23:59:59.000Z

228

Division of the momentum of electromagnetic waves in linear media into electromagnetic and material parts  

E-Print Network [OSTI]

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

229

Screening of electromagnetic field fluctuations by s--wave and d--wave superconductors  

E-Print Network [OSTI]

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.

Rachele Fermani; Stefan Scheel

2010-01-04T23:59:59.000Z

230

Geometric Phase Of The Faraday Rotation Of Electromagnetic Waves In Magnetized Plasma  

SciTech Connect (OSTI)

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.

Jian Liu and Hong Qin

2011-11-07T23:59:59.000Z

231

Effects of Electromagnetic Field on the Dynamical Instability of Cylindrical Collapse  

E-Print Network [OSTI]

The objective of this paper is to discuss the dynamical instability in the context of Newtonian and post Newtonian regimes. For this purpose, we consider non-viscous heat conducting charged isotropic fluid as a collapsing matter with cylindrical symmetry. Darmois junction conditions are formulated. The perturbation scheme is applied to investigate the influence of dissipation and electromagnetic field on the dynamical instability. We conclude that the adiabatic index $\\Gamma$ has smaller value for such a fluid in cylindrically symmetric than isotropic sphere.

M. Sharif; M. Azam

2012-03-16T23:59:59.000Z

232

Electromagnetically-Induced Frame-Dragging around Astrophysical Objects  

E-Print Network [OSTI]

Frame dragging (Lense-Thirring effect) is generally associated with rotating astrophysical objects. However, it can also be generated by electromagnetic fields if electric and magnetic fields are simultaneously present. In most models of astrophysical objects, macroscopic charge neutrality is assumed and the entire electromagnetic field is characterized in terms of a magnetic dipole component. Hence, the purely electromagnetic contribution to the frame dragging vanishes. However, strange stars may posses independent electric dipole and neutron stars independent electric quadrupole moments that may lead to the presence of purely electromagnetic contributions to the frame dragging. Moreover, recent observations have shown that in stars with strong electromagnetic fields, the magnetic quadrupole may have a significant contribution to the dynamics of stellar processes. As an attempt to characterized and quantify the effect of electromagnetic frame-dragging in this kind of astrophysical objects, an analytic soluti...

Ruiz, Andrs F Gutirrez

2015-01-01T23:59:59.000Z

233

Motor Packaging with Consideration of Electromagnetic and Material...  

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

& Publications Alnico and Ferrite Hybrid Excitation Electric Machines Motor Packaging with Consideration of Electromagnetic and Material Characteristics Electric Machine R&D...

234

Electromagnetic scattering and induction models for spheroidal geometries  

E-Print Network [OSTI]

Electromagnetic scattering from a medium containing randomly distributed discrete dielectric spheroidal inclusions is studied. Also, the broadband magnetoquasistatic solution for the induced magnetic field from a conducting ...

Barrowes, Benjamin E., 1973-

2004-01-01T23:59:59.000Z

235

Analysis Of Factors Affecting Natural Source Slf Electromagnetic...  

Open Energy Info (EERE)

relationship between the sensor orientation and the received artificial electromagnetic interference, influence of weather conditions on the data quality and so on. The results...

236

Design Optimization of electromagnetic actuator by genetic algorithm  

E-Print Network [OSTI]

condition in the design or in the optimization of ... efficient linear electromagnetic actuator with an .... derivative of the stored magnetic energy with respect.

ELBEZ

2008-02-26T23:59:59.000Z

237

Time-Domain Electromagnetics At Neal Hot Springs Geothermal Area...  

Open Energy Info (EERE)

Activity: Time-Domain Electromagnetics At Neal Hot Springs Geothermal Area (Colorado School of Mines and Imperial College London, 2011) Exploration Activity Details Location Neal...

238

Electromagnetic Soundings At Kilauea East Rift Geothermal Area...  

Open Energy Info (EERE)

of this study was to obtain a more complete model of the geologic structure and hydrology of Kilauea's east rift zone Notes Electromagnetic transient soundings were conducted...

239

6.013 Electromagnetics and Applications, Fall 2002  

E-Print Network [OSTI]

Electromagnetic phenomena are explored in modern applications including wireless communications, circuits, computer interconnects and peripherals, optical fiber links and components, microwave communications and radar, ...

Staelin, David H.

240

6.641 Electromagnetic Fields, Forces, and Motion, Spring 2003  

E-Print Network [OSTI]

Electric and magnetic quasistatic forms of Maxwell's equations applied to dielectric, conduction, and magnetization boundary value problems. Electromagnetic forces, force densities, and stress tensors, including magnetization ...

Zahn, Markus, 1946-

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Novel resonance-assisted electromagnetic-transport phenomena  

E-Print Network [OSTI]

We first demonstrate theoretically and experimentally that electromagnetic resonators with high quality factors (Q) can be used to transfer power efficiently over distances substantially larger than the characteristic ...

Kurs, Andr B

2011-01-01T23:59:59.000Z

242

Electromagnetic Soundings At Dixie Valley Geothermal Area (Mallan...  

Open Energy Info (EERE)

Mallan, Et Al., 2001) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Electromagnetic Soundings At Dixie Valley Geothermal Area (Mallan, Et Al.,...

243

Electromagnetically induced transparency controlled by a microwave field  

E-Print Network [OSTI]

interferences in electromagnetically induced transparency. A simple theoretical model and a numerical simulation have been developed to explain the observed experimental results....

Li, Hebin; Sautenkov, Vladimir A.; Rostovtsev, Yuri V.; Welch, George R.; Hemmer, Philip R.; Scully, Marlan O.

2009-01-01T23:59:59.000Z

244

Electromagnetic wave scattering by small perfectly conducting particles and applications  

E-Print Network [OSTI]

A formula for the electromagnetic (EM) field in the medium, in which many small perfectly conducting particles of an arbitrary shape are distributed, is derived.

Alexander G. Ramm

2014-02-13T23:59:59.000Z

245

Electromagnetic wave scattering by many conducting small particles  

E-Print Network [OSTI]

A rigorous theory of electromagnetic (EM) wave scattering by small perfectly conducting particles is developed. The limiting case when the number of particles tends to infinity is discussed.

A. G. Ramm

2008-04-21T23:59:59.000Z

246

Unification of Gravity and Electromagnetism II A Geometric Theory  

E-Print Network [OSTI]

It is shown that unification of gravity and electromagnetism can be achieved using an affine non-symmetric connection $\\Gamma^\\lambda_{\\mu\

Partha Ghose

2014-08-05T23:59:59.000Z

247

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 44, NO. 4, NOVEMBER 2002 495 A New Nonlinear Model of EMI-Induced  

E-Print Network [OSTI]

predictions. Index Terms--Demodulation, electromagnetic compatibility (EMC), electromagnetic interference (EMI are useful in the sizing of electromagnetic interference (EMI) filtering structures. Usually, RFI distortion

248

IEEE TRANSACTIONS ON ELECTROMAGNETIC COMPATIBILITY, VOL. 55, NO. 5, OCTOBER 2013 883 Characterization of Changes in LDO  

E-Print Network [OSTI]

sensitive to electromagnetic interference (EMI) coupled onto the power supply, with concomitant output--Ageing, electromagnetic compatibility (EMC), electromagnetic interference (EMI), immunity drift, low dropout (LDO) voltage

Paris-Sud XI, Université de

249

Generalized Terminal Modeling of Electromagnetic Interference  

SciTech Connect (OSTI)

Terminal models have been used for various applications. In this paper, a three-terminal model is proposed for electromagnetic-interference (EMI) characterization. The model starts with a power electronic system at a particular operating condition and creates a unique linearized equivalent circuit. Impedances and current/voltage sources define the noise throughout the entire EMI frequency spectrum. All parameters needed to create the model are clearly defined to ensure convergence and maximize accuracy. In addition, the accuracy of the model is confirmed up to 100 MHz for a dc-dc boost converter using both simulation and experimental validation.

Baisden, Andrew Carson [IEEE Industrial Applications Society; Boroyevich, Dushan [Virginia Polytechnic Institute and State University (Virginia Tech); Wang, Fei [ORNL

2010-01-01T23:59:59.000Z

250

Physics with the ALICE Electromagnetic Calorimeter  

E-Print Network [OSTI]

I will present physics measurements which are achievable in the ALICE experiment at the LHC through the inclusion of a new electromagnetic calorimeter. I will focus on jet measurements in proton proton and heavy ion collisions. Detailed simulations have been performed on jet reconstruction, jet triggering, heavy flavor jet reconstruction through electron identification, gamma-jet reconstruction and the measurements of identified hadrons and resonances in jets. I will show the physics capabilities which are made possible through the combination of calorimeter information with the other detector components in ALICE.

Rene Bellwied; for the ALICE Collaboration

2009-07-17T23:59:59.000Z

251

Electromagnetic wave scattering by small bodies  

E-Print Network [OSTI]

A reduction of the Maxwell's system to a Fredholm second-kind integral equation with weakly singular kernel is given for electromagnetic (EM) wave scattering by one and many small bodies. This equation is solved asymptotically as the characteristic size of the bodies tends to zero. The technique developed is used for solving the many-body EM wave scattering problem by rigorously reducing it to solving linear algebraic systems, completely bypassing the usage of integral equations. An equation is derived for the effective field in the medium, in which many small particles are embedded. A method for creating a desired refraction coefficient is outlined.

A. G. Ramm

2008-04-21T23:59:59.000Z

252

Electromagnetic wave scattering by many small particles  

E-Print Network [OSTI]

Scattering of electromagnetic waves by many small particles of arbitrary shapes is reduced rigorously to solving linear algebraic system of equations bypassing the usual usage of integral equations. The matrix elements of this linear algebraic system have physical meaning. They are expressed in terms of the electric and magnetic polarizability tensors. Analytical formulas are given for calculation of these tensors with any desired accuracy for homogeneous bodies of arbitrary shapes. An idea to create a "smart" material by embedding many small particles in a given region is formulated.

A. G. Ramm

2006-08-18T23:59:59.000Z

253

Electromagnetic Dipole Strength in Transitional Nuclei  

E-Print Network [OSTI]

Electromagnetic dipole absorption cross-sections of transitional nuclei with large-amplitude shape fluctuations are calculated in a microscopic way by introducing the concept of Instantaneous Shape Sampling. The concept bases on the slow shape dynamics as compared to the fast dipole vibrations. The elctromagnetic dipole strength is calculated by means of RPA for the instantaneous shapes, the probability of which is obtained by means of IBA. Very good agreement with the experimental absorption cross sections near the nucleon emission threshold is obtained.

S. Q. Zhang; I. Bentley; S. Brant; F. Dnau; S. Frauendorf; B. Kmpfer; R. Schwengner; A. Wagner

2008-08-19T23:59:59.000Z

254

Electromagnetic wormholes and virtual magnetic monopoles  

E-Print Network [OSTI]

We describe new configurations of electromagnetic (EM) material parameters, the electric permittivity $\\epsilon$ and magnetic permeability $\\mu$, that allow one to construct from metamaterials objects that function as invisible tunnels. These allow EM wave propagation between two points, but the tunnels and the regions they enclose are not detectable to EM observations. Such devices function as wormholes with respect to Maxwell's equations and effectively change the topology of space vis-a-vis EM wave propagation. We suggest several applications, including devices behaving as virtual magnetic monopoles.

Allan Greenleaf; Yaroslav Kurylev; Matti Lassas; Gunther Uhlmann

2007-03-20T23:59:59.000Z

255

Electromagnetic Properties of the Early Universe  

E-Print Network [OSTI]

Detailed physical processes of magnetic field generation from density fluctuations in the pre-recombination era are studied. Solving Maxwell equations and the generalized Ohm's law, the evolutions of the net charge density, the electric current and the electromagnetic field are solved. Unlike most of previous works, we treat electrons and photons as separate components under the assumption of tight coupling. We find that generation of the magnetic field due to density fluctuations takes place only from the second order of both perturbation theory and the tight coupling approximation.

Keitaro Takahashi; Kiyotomo Ichiki; Naoshi Sugiyama

2008-05-29T23:59:59.000Z

256

Nonlocal Electromagnetic Response of Graphene Nanostructures  

E-Print Network [OSTI]

Nonlocal electromagnetic effects of graphene arise from its naturally dispersive dielectric response. We present semi-analytical solutions of nonlocal Maxwell's equations for graphene nano-ribbons array with features around 100 nm, where we found prominent departures from its local response. Interestingly, the nonlocal corrections are stronger for light polarization parallel to the ribbons, which manifests as additional broadening of the Drude peak. For the perpendicular polarization case, nonlocal effects lead to blue-shifts of the plasmon peaks. These manifestations provide a physical measure of nonlocal effects, and we quantify their dependence on ribbon width, doping and wavelength.

Fallahi, Arya; Tamagnone, Michele; Perruisseau-Carrier, Julien

2014-01-01T23:59:59.000Z

257

Immunizing digital systems against electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant`s electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. [Oak Ridge National Lab., TN (United States); Antonescu, C. [Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research

1993-02-01T23:59:59.000Z

258

Immunizing digital systems against electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Secondly, a test and evaluation program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate test limits to ensure that the circuit or system under test meets the recommended guidelines. Test and evaluation should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation problems associated with EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. (Oak Ridge National Lab., TN (United States)); Antonescu, C. (Nuclear Regulatory Commission, Washington, DC (United States). Office of Nuclear Regulatory Research)

1993-01-01T23:59:59.000Z

259

Discrimination of partial discharge electromagnetic signal in SF{sub 6} gas from external noises using phase gate control method  

SciTech Connect (OSTI)

The authors proposed phase gate control method for distinguishing frequency spectrum of electromagnetic wave caused by partial discharge (PD) in SF{sub 6} gas from external noises. They investigated the dependence of the polarity and phase angle of ac voltage on the electromagnetic wave spectrum. They derived the frequency region where PD spectrum caused by SF{sub 6} gas can be detected under noisy conditions. The authors also related quantitatively the gain of electromagnetic wave spectrum to the maximum PD charge simultaneously occurring in both SF{sub 6} gas and air. On the basis of these results, they determined the minimum detectable PD level in SF{sub 6} gas under noisy conditions as a function of measuring frequency.

Hikita, M.; Hoshino, T.; Kato, T.; Hayakawa, N.; Okubo, H. [Nagoya Univ. (Japan); Ueda, T. [Chubu Electric Power Co., Inc., Nagoya (Japan)

1996-12-31T23:59:59.000Z

260

Progress In Electromagnetics Research B, Vol. 37, 205235, 2012 DERIVATION OF HOMOGENEOUS PERMITTIVITY OF  

E-Print Network [OSTI]

for engineering electromagnetic absorbing composite materials, for example, containing carbon fibers. The causal PERMITTIVITY OF COMPOSITE MATERIALS WITH ALIGNED CYLINDRI- CAL INCLUSIONS FOR CAUSAL ELECTROMAGNETIC Debye representation is important for incorporation of a composite material in numerical electromagnetic

Koledintseva, Marina Y.

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Simulation and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High Frequency Electronic Systems.  

E-Print Network [OSTI]

Simulation and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High and Modeling Techniques for Signal Integrity and Electromagnetic Interference on High Frequency Electronic Integrity and Electromagnetic Interference on High Frequency Electronic Systems. by Luca Daniel Doctor

Daniel, Luca

262

Fast Electromagnetic Interference Analysis of Distributed Networks using Longitudinal Partitioning Based Waveform Relaxation  

E-Print Network [OSTI]

Fast Electromagnetic Interference Analysis of Distributed Networks using Longitudinal Partitioning -- In this paper, a waveform relaxation algorithm for the fast electromagnetic interference analysis of distributed is provided to demonstrate the validity of the proposed algorithm. Index Terms -- Electromagnetic interference

Roy, Sourajeet

263

PERGAMON Carbon 39 (2001) 279285 Electromagnetic interference shielding effectiveness of carbon  

E-Print Network [OSTI]

PERGAMON Carbon 39 (2001) 279­285 Review Electromagnetic interference shielding effectiveness materials for electromagnetic interference (EMI) shielding are reviewed. They include composite materials-structural and structural composites, colloi- dal graphite, as well as EMI gasket materials. Electromagnetic interference

Chung, Deborah D.L.

264

Electromagnetic interference shielding using continuous carbon-fiber carbon-matrix and polymer-matrix composites  

E-Print Network [OSTI]

Electromagnetic interference shielding using continuous carbon-fiber carbon-matrix and polymer electromagnetic interference (EMI) shielding material with shielding effectiveness 124 dB, low surface impedance interference shielding 1. Introduction Electromagnetic interference (EMI) shielding is receiv- ing increasing

Chung, Deborah D.L.

265

Accident Investigations  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

This Order prescribes organizational responsibilities, authorities, and requirements for conducting investigations of certain accidents occurring at DOE sites, facilities, areas, operations, and activities.

2011-03-04T23:59:59.000Z

266

Electromagnetic models of the lightning return stroke Yoshihiro Baba1  

E-Print Network [OSTI]

Electromagnetic models of the lightning return stroke Yoshihiro Baba1 and Vladimir A. Rakov2] Lightning return-stroke models are needed for specifying the source in studying the production of transient-called engineering models, electromagnetic return-stroke models allow a self-consistent full-wave solution for both

Florida, University of

267

Electromagnetic Interference (EMI) Resisting Analog Integrated Circuit Design Tutorial  

E-Print Network [OSTI]

ELECTROMAGNETIC INTERFERENCE (EMI) RESISTING ANALOG INTEGRATED CIRCUIT DESIGN TUTORIAL A Thesis by JINGJING YU Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements... for the degree of MASTER OF SCIENCE August 2012 Major Subject: Electrical Engineering ELECTROMAGNETIC INTERFERENCE (EMI) RESISTING ANALOG INTEGRATED CIRCUIT DESIGN TUTORIAL A Thesis by JINGJING YU Submitted to the Office...

Yu, Jingjing

2012-10-19T23:59:59.000Z

268

On Generating Gravity Waves with Matter and Electromagnetic Waves  

E-Print Network [OSTI]

If a homogeneous plane light-like shell collides head-on with a homogeneous plane electromagnetic shock wave having a step-function profile then no backscattered gravitational waves are produced. We demonstrate, by explicit calculation, that if the matter is accompanied by a homogeneous plane electromagnetic shock wave with a step-function profile then backscattered gravitational waves appear after the collision.

C. Barrabes; P. A. Hogan

2008-04-05T23:59:59.000Z

269

Material Surface Design to Counter Electromagnetic Interrogation of Targets  

E-Print Network [OSTI]

Material Surface Design to Counter Electromagnetic Interrogation of Targets H.T. Banks, K. Ito, G and ferromagnetic layers coat- ing a conducting object to provide an attenuation capability against electro. Fresnel's law for the reflectance index is extended to the electromagnetic propagation in anisotropic

270

Electromagnetic space-time crystals. II. Fractal computational approach  

E-Print Network [OSTI]

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.

G. N. Borzdov

2014-10-20T23:59:59.000Z

271

Electromagnetic field at Finite Temperature: A first order approach  

E-Print Network [OSTI]

In this work we study the electromagnetic field at Finite Temperature via the massless DKP formalism. The constraint analysis is performed and the partition function for the theory is constructed and computed. When it is specialized to the spin 1 sector we obtain the well-known result for the thermodynamic equilibrium of the electromagnetic field.

R. Casana; B. M. Pimentel; J. S. Valverde

2007-02-04T23:59:59.000Z

272

Electromagnetic Wellbore Heating C. Sean Bohun, The Pennsylvania State University,  

E-Print Network [OSTI]

Electromagnetic Wellbore Heating C. Sean Bohun, The Pennsylvania State University, Bruce McGee, Mc Workshop, June 2000. 1 Introduction In this paper we derive a simple model that describes the recovery of petroleum fluids from an oil reservoir by the method of electromagnetic heating. By its very nature

Bohun, C. Sean

273

Electromagnetic actuator to reduce vibration sources Thibaut Chailloux*  

E-Print Network [OSTI]

in an FE- Tuned Magnetic Equivalent Circuit of an Electromagnetic Relay, Sixdenier F., Raulet M.-A., MarionElectromagnetic actuator to reduce vibration sources Thibaut Chailloux* , L. Morel* , F. Sixdenier In order to improve passenger comfort, a reduction of vibration sources in vehicles is being considered

Paris-Sud XI, Université de

274

Line geometry and electromagnetism III: groups of transformations  

E-Print Network [OSTI]

The role of linear and projective groups of transformations in line geometry and electromagnetism is examined in accordance with Klein's Erlanger Programm for geometries. The group of collineations of real projective space is chosen as the most general group, and reductions to some of its various subgroups are then detailed according to their relevance to electromagnetic fields, and especially wave-like ones.

D. H. Delphenich

2014-04-16T23:59:59.000Z

275

Electromagnetic field of a charge intersecting a cold plasma boundary in a waveguide  

SciTech Connect (OSTI)

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.

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

276

Electromagnetic waves destabilized by runaway electrons in near-critical electric fields  

SciTech Connect (OSTI)

Runaway electron distributions are strongly anisotropic in velocity space. This anisotropy is a source of free energy that may destabilize electromagnetic waves through a resonant interaction between the waves and the energetic electrons. In this work, we investigate the high-frequency electromagnetic waves that are destabilized by runaway electron beams when the electric field is close to the critical field for runaway acceleration. Using a runaway electron distribution appropriate for the near-critical case, we calculate the linear instability growth rate of these waves and conclude that the obliquely propagating whistler waves are most unstable. We show that the frequencies, wave numbers, and propagation angles of the most unstable waves depend strongly on the magnetic field. Taking into account collisional and convective damping of the waves, we determine the number density of runaways that is required to destabilize the waves and show its parametric dependences.

Komar, A.; Pokol, G. I. [Department of Nuclear Techniques, Budapest University of Technology and Economics, Association EURATOM, H-1111 Budapest (Hungary); Fueloep, T. [Department of Applied Physics, Nuclear Engineering, Chalmers University of Technology and Euratom-VR Association, Goeteborg (Sweden)

2013-01-15T23:59:59.000Z

277

Electromagnetic field with induced massive term: Case with scalar field  

E-Print Network [OSTI]

We consider an interacting system of massless scalar and electromagnetic field, with the Lagrangian explicitly depending on the electromagnetic potentials, i.e., interaction with broken gauge invariance. The Lagrangian for interaction is chosen in such a way that the electromagnetic field equation acquires an additional term, which in some cases is proportional to the vector potential of the electromagnetic field. This equation can be interpreted as the equation of motion of photon with induced nonzero rest-mass. This system of interacting fields is considered within the scope of Bianchi type-I (BI) cosmological model. It is shown that, as a result of interaction the electromagnetic field vanishes at $t \\to \\infty$ and the isotropization process of the expansion takes place.

Yu. P. Rybakov; G. N. Shikin; Yu. A. Popov; Bijan Saha

2010-04-21T23:59:59.000Z

278

Electromagnetic Mass Models in General Theory of Relativity  

E-Print Network [OSTI]

"Electromagnetic mass" where gravitational mass and other physical quantities originate from the electromagnetic field alone has a century long distinguished history. In the introductory chapter we have divided this history into three broad categories -- classical, quantum mechanical and general relativistic. Each of the categories has been described at a length to get the detailed picture of the physical background. Recent developments on Repulsive Electromagnetic Mass Models are of special interest in this introductory part of the thesis. In this context we have also stated motivation of our work. In the subsequent chapters we have presented our results and their physical significances. It is concluded that the electromagnetic mass models which are the sources of purely electromagnetic origin ``have not only heuristic flavor associated with the conjecture of Lorentz but even a physics having unconventional yet novel features characterizing their own contributions independent of the rest of the physics".

Sumana Bhadra

2007-10-30T23:59:59.000Z

279

Electromagnetic field with induced massive term: Case with spinor field  

E-Print Network [OSTI]

We consider an interacting system of spinor and electromagnetic field, explicitly depending on the electromagnetic potentials, i.e., interaction with broken gauge invariance. The Lagrangian for interaction is chosen in such a way that the electromagnetic field equation acquires an additional term, which in some cases is proportional to the vector potential of the electromagnetic field. This equation can be interpreted as the equation of motion of photon with induced non-trivial rest-mass. This system of interacting spinor and scalar fields is considered within the scope of Bianchi type-I (BI) cosmological model. It is shown that, as a result of interaction the electromagnetic field vanishes at $t \\to \\infty$ and the isotropization process of the expansion takes place.

Yu. P. Rybakov; G. N. Shikin; Yu. A. Popov; Bijan Saha

2010-08-12T23:59:59.000Z

280

E-Print Network 3.0 - ac electromagnetic field Sample Search...  

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

Topics (time permitting). 12;The Nature of Electromagnetism Electric and magnetic fields... that are coupled; they are then referred to as an electromagnetic field....

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

E-Print Network 3.0 - active electromagnetic interference Sample...  

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

electromagnetic interference Search Powered by Explorit Topic List Advanced Search Sample search results for: active electromagnetic interference Page: << < 1 2 3 4 5 > >> 1...

282

Medium Voltage Overhead Power-line Broadband Communications; Transmission Capacity and Electromagnetic Interference  

E-Print Network [OSTI]

and Electromagnetic Interference P. Amirshahi and M. Kavehrad (FIEEE) The Pennsylvania State University, Department distribution networks for broadband power-line communications applications. Electromagnetic interference

Kavehrad, Mohsen

283

1. Shielding against Electromagnetic Interference With telecommunication networks connecting wireless devices around the globe, there  

E-Print Network [OSTI]

#12;1. Shielding against Electromagnetic Interference With telecommunication networks connecting electromagnetic interference (EMI) across the airwaves. These communication networks are ubiquitous and dynamic

Rincon-Mora, Gabriel A.

284

E-Print Network 3.0 - account electromagnetic transient Sample...  

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

electromagnetic transient Search Powered by Explorit Topic List Advanced Search Sample search results for: account electromagnetic transient Page: << < 1 2 3 4 5 > >> 1 Frontiers...

285

Electromagnetic waves with nonlinear dispersion law  

E-Print Network [OSTI]

Last year physicists in Europe have measured the velocity of the neutrinos particles. They found the neutrinos moving faster than the speed of light in vacuum. This result means that Einstein's relativity principle and its consequences in modern physics need a global additional renovation. In present paper the part of this problem is considered in terms of basic Maxwell's method only. By means of introduction a diffusion like displacement current the new super wave equation was derived, which permits of its solution be described the electromagnetic waves moving some faster than the conventional speed of light in vacuum especially in a gamma ray of a very short wave length region. The unique properties of these waves are that they undergo nonlinear dispersion law, uppermost limit of which is restricted. Discussion of further experimental problems and a number of estimations are given for the macro physic super wave equations also.

Pavel Mednis

2012-02-08T23:59:59.000Z

286

Emergent cosmological constant from colliding electromagnetic waves  

E-Print Network [OSTI]

In this study we advocate the view that the cosmological constant is of electromagnetic (em) origin, which can be generated from the collision of em shock waves coupled with gravitational shock waves. The wave profiles that participate in the collision have different amplitudes. It is shown that, circular polarization with equal amplitude waves does not generate cosmological constant. We also prove that the generation of the cosmological constant is related to the linear polarization. The addition of cross polarization generates no cosmological constant. Depending on the value of the wave amplitudes, the generated cosmological constant can be positive or negative. We show additionally that, the collision of nonlinear em waves in a particular class of Born-Infeld theory also yields a cosmological constant.

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

2014-10-15T23:59:59.000Z

287

Theory of Dipole Induced Electromagnetic Transparency  

E-Print Network [OSTI]

A detailed theory describing linear optics of vapors comprised of interacting multi-level quantum emitters is proposed. It is shown both by direct integration of Maxwell-Bloch equations and using a simple analytical model that at large densities narrow transparency windows appear in otherwise completely opaque spectra. The existence of such windows is attributed to overlapping resonances. This effect, first introduced for three-level systems in [R. Puthumpally-Joseph, M. Sukharev, O. Atabek and E. Charron, Phys. Rev. Lett. 113, 163603 (2014)], is due to strongly enhanced dipole-dipole interactions at high emitters' densities. The presented theory extends this effect to the case of multilevel systems. The theory is applied to the D1 transitions of interacting Rb-85 atoms. It is shown that at high atomic densities, Rb-85 atoms can behave as three-level emitters exhibiting all the properties of dipole induced electromagnetic transparency. Applications including slow light and laser pulse shaping are also propose...

Puthumpally-Joseph, Raiju; Sukharev, Maxim; Charron, Eric

2015-01-01T23:59:59.000Z

288

Electromagnetic matrix elements for negative parity nucleons  

E-Print Network [OSTI]

Here we present preliminary results for the evaluation of the electromagnetic form factors for the lowest-lying negative-parity, spin-$\\frac{1}{2}$ nucleons, namely the $S_{11}(1535)$ and $S_{11}(1650)$, through the use of the variational method. We find that the characteristics of the electric form factor, $G_{E}$, are similar between these states, however significant differences are observed between the quark-sector contributions to the magnetic form factor, $G_{M}$. Within simple constituent quark models, these states are understood to be admixtures of $s=\\frac{1}{2}$ and $s=\\frac{3}{2}$ states coupled to orbital angular momentum $\\ell = 1$. Our results reveal a qualitative difference in the manner in which the singly-represented quark sector contributes to these baryon magnetic form factors.

Benjamin Owen; Waseem Kamleh; Derek Leinweber; Selim Mahbub; Benjamin Menadue

2014-12-15T23:59:59.000Z

289

Electromagnetic mass difference on the lattice  

E-Print Network [OSTI]

We calculate electromagnetic mass difference of mesons using a method proposed by Duncan {\\it et al}. The RG-improved gauge action and the non-compact Abelian gauge action are employed to generate configurations. Quark propagators in the range of $m_{PS}/m_{V}=0.76-0.51$ are obtained with the meanfield-improved clover quark action. Chiral and continuum extrapolations are performed and the results are compared with experiments. Finite size effects are also examined. Quark masses are extracted from the measured spectrum. Our preliminary values for light quark masses are $m_{u}^{\\bar{MS}}(\\mu =2 {GeV}) = 3.03(19)$ MeV, $m_{d}^{\\bar{MS}}(\\mu = 2 {GeV}) = 4.44(28)$ MeV, $m_{s}^{\\bar{MS}}(\\mu = 2 {GeV}) = 99.2(52)$ MeV.

Yusuke Namekawa; Yoshio Kikukawa

2005-09-24T23:59:59.000Z

290

INNOVATIVE ELECTROMAGNETIC SENSORS FOR PIPELINE CRAWLERS  

SciTech Connect (OSTI)

Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they encounter. Recent development efforts include a new generation of powered inspection platforms that crawl slowly inside a pipeline and are able to maneuver past the physical barriers that can limit inspection. At Battelle, innovative electromagnetic sensors are being designed and tested for these new pipeline crawlers. The various sensor types can be used to assess a wide range of pipeline anomalies including corrosion, mechanical damage, and cracks. The Applied Energy Systems Group at Battelle is concluding the first year of work on a projected three-year development effort. In this first year, two innovative electromagnetic inspection technologies were designed and tested. Both were based on moving high-strength permanent magnets to generate inspection energy. One system involved translating permanent magnets towards the pipe. A pulse of electric current would be induced in the pipe to oppose the magnetization according to Lenz's Law. The decay of this pulse would indicate the presence of defects in the pipe wall. This inspection method is similar to pulsed eddy current inspection methods, with the fundamental difference being the manner in which the current is generated. Details of this development effort were reported in the first semiannual report on this project. This second semiannual report focuses on the development of a second inspection methodology, based on rotating permanent magnets. During this period, a rotating permanent magnet exciter was designed and built. The exciter unit produces strong eddy currents in the pipe wall. The tests have shown that at distances of a pipe diameter or more, the currents flow circumferentially, and that these circumferential currents are deflected by pipeline defects such as corrosion and axially aligned cracks. Simple sensors are used to detect the change in current densities in the pipe wall.

J. Bruce Nestleroth

2004-11-05T23:59:59.000Z

291

Inferring black hole charge from backscattered electromagnetic radiation  

E-Print Network [OSTI]

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.

Lus C. B. Crispino; Sam R. Dolan; Atsushi Higuchi; Ednilton S. de Oliveira

2014-09-16T23:59:59.000Z

292

Electromagnetic quasinormal modes of D-dimensional black holes II  

E-Print Network [OSTI]

By using the sixth order WKB approximation we calculate for an electromagnetic field propagating in D-dimensional Schwarzschild and Schwarzschild de Sitter black holes its quasinormal frequencies for the fundamental mode and first overtones. We study the dependence of these QN frequencies on the value of the cosmological constant and the spacetime dimension. We also compare with the known results for the gravitational perturbations propagating in the same background. Moreover we exactly compute the QN frequencies of the electromagnetic field propagating in D-dimensional massless topological black hole and for charged D-dimensional Nariai spacetime we exactly calculate the QN frequencies of the coupled electromagnetic and gravitational perturbations.

A. Lpez-Ortega

2007-06-20T23:59:59.000Z

293

A Full Review of the Theory of Electromagnetism  

E-Print Network [OSTI]

We will provide detailed arguments showing that the set of Maxwell equations, and the corresponding wave equations, do not properly describe the evolution of electromagnetic wave-fronts. We propose a nonlinear corrected version that is proven to be far more appropriate for the modellization of electromagnetic phenomena. The suitability of this approach will soon be evident to the reader, through a sequence of astonishing congruences, making the model as elegant as Maxwell's, but with increased chances of development. Actually, the new set of equations will allow us to explain many open questions, and find links between electromagnetism and other theories that have been searched for a long time, or not even imagined.

D. Funaro

2005-05-09T23:59:59.000Z

294

Theory of electromagnetic fluctuations for magnetized multi-species plasmas  

SciTech Connect (OSTI)

Analysis of electromagnetic fluctuations in plasma provides relevant information about the plasma state and its macroscopic properties. In particular, the solar wind persistently sustains a small but detectable level of magnetic fluctuation power even near thermal equilibrium. These fluctuations may be related to spontaneous electromagnetic fluctuations arising from the discreteness of charged particles. Here, we derive general expressions for the plasma fluctuations in a multi-species plasma following arbitrary distribution functions. This formalism, which generalizes and includes previous works on the subject, is then applied to the generation of electromagnetic fluctuations propagating along a background magnetic field in a plasma of two proton populations described by drifting bi-Maxwellians.

Navarro, Roberto E., E-mail: roberto.navarro@ug.uchile.cl; Muoz, Vctor [Departamento de Fsica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Araneda, Jaime [Departamento de Fsica, Universidad de Concepcin, Concepcin 4070386 (Chile); Moya, Pablo S. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Department of Physics, Catholic University of America, Washington, D. C. 20064 (United States); Vias, Adolfo F. [NASA Goddard Space Flight Center, Heliophysics Science Division, Geospace Physics Laboratory, Mail Code 673, Greenbelt, Maryland 20771 (United States); Valdivia, Juan A. [Departamento de Fsica, Facultad de Ciencias, Universidad de Chile, Casilla 653, Santiago (Chile); Centro de Estudios Interdisciplinarios Bsicos y Aplicados en Complejidad, CEIBA complejidad, Bogot (Colombia)

2014-09-15T23:59:59.000Z

295

Electromagnetic wave propagation through an overdense magnetized collisional plasma layer  

SciTech Connect (OSTI)

The results of investigations into the feasibility of using a magnetic window to propagate electromagnetic waves through a finite-sized overdense plasma slab are described. We theoretically calculate the transmission coefficients for right- and left-handed circularly polarized plane waves through a uniform magnetized plasma slab. Using reasonable estimates for the plasma properties expected to be found in the ionized shock layer surrounding a hypersonic aircraft traveling in the earth's upper atmosphere (radio blackout conditions), and assuming a 1 GHz carrier frequency for the radio communications channel, we find that the required magnetic field for propagation of right-handed circularly polarized, or whistler, waves is on the order of a few hundred gauss. Transmission coefficients are calculated as a function of sheath thickness and are shown to be quite sensitive to the electron collision frequency. One-dimensional particle-in-cell simulations are shown to be in good agreement with the theory. These simulations also demonstrate that Ohmic heating of the electrons can be considerable. Two- and three-dimensional particle-in-cell simulations using a simplified waveguide and antenna model illustrate the same general transmission behavior as the theory and one-dimensional simulations. In addition, a net focusing effect due to the plasma is also observed in two and three dimensions. These simulations can be extended to design and analyze more realistic waveguide and antenna models.

Thoma, C.; Rose, D. V.; Miller, C. L.; Clark, R. E.; Hughes, T. P. [Voss Scientific LLC, Albuquerque, New Mexico 87108 (United States)

2009-08-15T23:59:59.000Z

296

Effects of thermal motion on electromagnetically induced absorption  

E-Print Network [OSTI]

We describe the effect of thermal motion and buffer-gas collisions on a four-level closed N system interacting with strong pump(s) and a weak probe. This is the simplest system that experiences electromagnetically induced absorption (EIA) due to transfer of coherence via spontaneous emission from the excited to ground state. We investigate the influence of Doppler broadening, velocity-changing collisions (VCC), and phase-changing collisions (PCC) with a buffer gas on the EIA spectrum of optically active atoms. In addition to exact expressions, we present an approximate solution for the probe absorption spectrum, which provides physical insight into the behavior of the EIA peak due to VCC, PCC, and wave-vector difference between the pump and probe beams. VCC are shown to produce a wide pedestal at the base of the EIA peak, which is scarcely affected by the pump-probe angular deviation, whereas the sharp central EIA peak becomes weaker and broader due to the residual Doppler-Dicke effect. Using diffusion-like equations for the atomic coherences and populations, we construct a spatial-frequency filter for a spatially structured probe beam and show that Ramsey narrowing of the EIA peak is obtained for beams of finite width.

E. Tilchin; O. Firstenberg; A. D. Wilson-Gordon

2011-07-04T23:59:59.000Z

297

A large volume uniform plasma generator for the experiments of electromagnetic wave propagation in plasma  

SciTech Connect (OSTI)

A large volume uniform plasma generator is proposed for the experiments of electromagnetic (EM) wave propagation in plasma, to reproduce a 'black out' phenomenon with long duration in an environment of the ordinary laboratory. The plasma generator achieves a controllable approximate uniform plasma in volume of 260 mm Multiplication-Sign 260 mm Multiplication-Sign 180 mm without the magnetic confinement. The plasma is produced by the glow discharge, and the special discharge structure is built to bring a steady approximate uniform plasma environment in the electromagnetic wave propagation path without any other barriers. In addition, the electron density and luminosity distributions of plasma under different discharge conditions were diagnosed and experimentally investigated. Both the electron density and the plasma uniformity are directly proportional to the input power and in roughly reverse proportion to the gas pressure in the chamber. Furthermore, the experiments of electromagnetic wave propagation in plasma are conducted in this plasma generator. Blackout phenomena at GPS signal are observed under this system and the measured attenuation curve is of reasonable agreement with the theoretical one, which suggests the effectiveness of the proposed method.

Yang Min; Li Xiaoping; Xie Kai; Liu Donglin [School of Electronical and Mechanical Engineering, Xidian University, Xi'an Shaanxi 710071 (China); Liu Yanming [School of Telecommunications Engineering, Xidian University, Xi'an Shaanxi 710071 (China)

2013-01-15T23:59:59.000Z

298

Resistive wall tearing mode generated finite net electromagnetic torque in a static plasma  

SciTech Connect (OSTI)

The MARS-F code [Y. Q. Liu et al., Phys. Plasmas 7, 3681 (2000)] is applied to numerically investigate the effect of the plasma pressure on the tearing mode stability as well as the tearing mode-induced electromagnetic torque, in the presence of a resistive wall. The tearing mode with a complex eigenvalue, resulted from the favorable averaged curvature effect [A. H. Glasser et al., Phys. Fluids 18, 875 (1975)], leads to a re-distribution of the electromagnetic torque with multiple peaking in the immediate vicinity of the resistive layer. The multiple peaking is often caused by the sound wave resonances. In the presence of a resistive wall surrounding the plasma, a rotating tearing mode can generate a finite net electromagnetic torque acting on the static plasma column. Meanwhile, an equal but opposite torque is generated in the resistive wall, thus conserving the total momentum of the whole plasma-wall system. The direction of the net torque on the plasma is always opposite to the real frequency of the mode, agreeing with the analytic result by Pustovitov [Nucl. Fusion 47, 1583 (2007)]. When the wall time is close to the oscillating time of the tearing mode, the finite net torque reaches its maximum. Without wall or with an ideal wall, no net torque on the static plasma is generated by the tearing mode. However, re-distribution of the torque density in the resistive layer still occurs.

Hao, G. Z., E-mail: haogz@swip.ac.cn; Wang, A. K.; Xu, M.; Qu, H. P.; Peng, X. D.; Wang, Z. H.; Xu, J. Q.; Qiu, X. M. [Southwestern Institute of Physics, Post Office Box 432, Chengdu 610041 (China)] [Southwestern Institute of Physics, Post Office Box 432, Chengdu 610041 (China); Liu, Y. Q. [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)] [Euratom/CCFE Fusion Association, Culham Science Centre, Abingdon OX14 3DB (United Kingdom)

2014-01-15T23:59:59.000Z

299

Accident Investigations  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To prescribe requirements for conducting investigations of certain accidents occurring at Department of Energy (DOE) operations and sites; to improve the environment, safety and health for DOE, contractors, and the public; and to prevent the recurrence of such accidents. Chg 2, 4-26-96

1996-04-26T23:59:59.000Z

300

Accident Investigations  

Broader source: Directives, Delegations, and Requirements [Office of Management (MA)]

To prescribe requirements for conducting investigations of certain accidents occurring at Department of Energy (DOE) operations and sites; to improve the environment , safety and health for DOE, contractors, and the public; and to prevent the recurrence of such accidents. Chg 1, 10-26-95. Cancels parts of DOE 5484.1

1995-10-26T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

ON THE INFLUENCE OF THE GEOMETRY ON SKIN EFFECT IN ELECTROMAGNETISM  

E-Print Network [OSTI]

ON THE INFLUENCE OF THE GEOMETRY ON SKIN EFFECT IN ELECTROMAGNETISM GABRIEL CALOZ, MONIQUE DAUGE, ERWAN FAOU, VICTOR P´ERON ABSTRACT. We consider the equations of electromagnetism set on a domain made in electromagnetism. This effect describes the rapid decay of electromagnetic fields with depth inside a metallic

Dauge, Monique

302

Graphene-based nano-antennas for electromagnetic nanocommunications in the terahertz band  

E-Print Network [OSTI]

graphene-based electronics have opened the door to electromagnetic communications in the nanoscale. In this

Josep Miquel Jornet; Ian F. Akyildiz

2010-01-01T23:59:59.000Z

303

Electromagnetic Extraction and Annihilation of Antiprotons for Spacecraft Propulsion  

E-Print Network [OSTI]

. Zayas, Raymond J. Sedwick May, 2008 SSL # 3-08 #12;#12;Electromagnetic Extraction and Annihilation of Antiprotons for Spacecraft Propulsion Daniel A. Zayas, Raymond J. Sedwick May, 2008 SSL # 3-08 This work

304

K -> pi pi Phenomenology in the Presence of Electromagnetism  

E-Print Network [OSTI]

We describe the influence of electromagnetism on the phenomenology of K -> pi pi decays. This is required because the present data were analyzed without inclusion of electromagnetic radiative corrections, and hence contain several ambiguities and uncertainties which we describe in detail. Our presentation includes a full description of the infrared effects needed for a new experimental analysis. It also describes the general treatment of final state interaction phases, needed because Watson's theorem is no longer valid in the presence of electromagnetism. The phase of the isospin-two amplitude A_2 may be modified by 50% -> 100%. We provide a tentative analysis using present data in order to illustrate the sensitivity to electromagnetic effects, and also discuss how the standard treatment of epsilon'/epsilon is modified.

Vincenzo Cirigliano; John F. Donoghue; Eugene Golowich

2000-08-28T23:59:59.000Z

305

Low-cost electromagnetic tagging : design and implementation  

E-Print Network [OSTI]

Several implementations of chipless RFID (Radio Frequency Identification) tags are presented and discussed as low-cost alternatives to chip-based RFID tags and sensors. An overview of present-day near-field electromagnetic ...

Fletcher, Richard R. (Richard Ribon)

2002-01-01T23:59:59.000Z

306

Exploring the Last Electromagnetic Frontier with the Long Wavelength Array  

E-Print Network [OSTI]

LWA Science with the Long Wavelength Demonstrator Array Radio transients offer a new frontier for next-generationExploring the Last Electromagnetic Frontier with the Long Wavelength Array The University of New. All solar system giant planets generate

Ellingson, Steven W.

307

Design of high temperature high speed electromagnetic axial thrust bearing  

E-Print Network [OSTI]

DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree... of MASTER OF SCIENCE December 2002 Major Subject: Mechanical Engineering DESIGN OF HIGH TEMPERATURE HIGH SPEED ELECTROMAGNETIC AXIAL THRUST BEARING A Thesis by MOHAMMAD WAQAR MOHIUDDIN Submitted to Texas A&M University in partial fulfillment...

Mohiuddin, Mohammad Waqar

2002-01-01T23:59:59.000Z

308

Electromagnetic quasinormal modes of an asymptotically Lifshitz black hole  

E-Print Network [OSTI]

Motivated by the recent interest in the study of the spacetimes that are asymptotically Lifshitz and in order to extend some previous results, we calculate exactly the quasinormal frequencies of the electromagnetic field in a D-dimensional asymptotically Lifshitz black hole. Based on the values obtained for the quasinormal frequencies we discuss the classical stability of the quasinormal modes. We also study whether the electromagnetic field possesses unstable modes in the D-dimensional Lifshitz spacetime.

A. Lopez-Ortega

2014-06-01T23:59:59.000Z

309

Electromagnetic quasinormal modes of D-dimensional black holes  

E-Print Network [OSTI]

Using the monodromy method we calculate the asymptotic quasinormal (QN) frequencies of an electromagnetic field moving in D-dimensional Schwarzschild and Schwarzschild de Sitter (SdS) black holes ($D\\geq 4$). For the D-dimensional Schwarzschild anti-de Sitter (SadS) black hole we also compute these frequencies with a similar method. Moreover, we calculate the electromagnetic normal modes of the D-dimensional anti-de Sitter (AdS) spacetime.

A. Lpez-Ortega

2006-11-02T23:59:59.000Z

310

Electromagnetic vertex function of the pion at T > 0  

E-Print Network [OSTI]

The matrix element of the electromagnetic current between pion states is calculated in quenched lattice QCD at a temperature of $T = 0.93 T_c$. The nonperturbatively improved Sheikholeslami-Wohlert action is used together with the corresponding ${\\cal O}(a)$ improved vector current. The electromagnetic vertex function is extracted for pion masses down to $360 {\\rm MeV}$ and momentum transfers $Q^2 \\le 2.7 {\\rm GeV}^2$.

J. van der heide; J. H. Koch; E. Laermann

2005-12-23T23:59:59.000Z

311

Effects of Electromagnetic Fields on Fish and Invertebrates  

SciTech Connect (OSTI)

In this progress report, we describe the preliminary experiments conducted with three fish and one invertebrate species to determine the effects of exposure to electromagnetic fields. During fiscal year 2010, experiments were conducted with coho salmon (Onchrohychus kisutch), California halibut (Paralicthys californicus), Atlantic halibut (Hippoglossus hippoglossus), and Dungeness crab (Cancer magister). The work described supports Task 2.1.3: Effects on Aquatic Organisms, Subtask 2.1.3.1: Electromagnetic Fields.

Schultz, Irvin R.; Woodruff, Dana L.; Marshall, Kathryn E.; Pratt, William J.; Roesijadi, Guritno

2010-10-13T23:59:59.000Z

312

The Stability of a Shearing Viscous Star with Electromagnetic Field  

E-Print Network [OSTI]

We analyze the role of electromagnetic field for the stability of shearing viscous star with spherical symmetry. Matching conditions are given for the interior and exterior metrics. We use perturbation scheme to construct the collapse equation. The range of instability is explored in Newtonian and post Newtonian (pN) limits. We conclude that the electromagnetic field diminishes the effects of shearing viscosity in the instability range and makes the system more unstable at both Newtonian and post Newtonian approximations.

M. Sharif; M. Azam

2013-12-04T23:59:59.000Z

313

Calibrating Accelerometers Using an Electromagnetic Launcher  

SciTech Connect (OSTI)

A Pulse Forming Network (PFN), Helical Electromagnetic Launcher (HEML), Command Module (CM), and Calibration Table (CT) were built and evaluated for the combined ability to calibrate an accelerometer. The PFN has a maximum stored energy of 19.25 kJ bank and is fired by a silicon controlled rectifier (SCR), with appropriate safety precautions. The HEML is constructed out of G-10 fiberglass and is designed to accelerate 600 grams to 10 meters per second. The CM is microcontroller based running Arduino Software. The CM has a keypad input and 7 segment outputs of the bank voltage and desired voltage. After entering a desired bank voltage, the CM controls the charge of the PFN. When the two voltages are equal it allows the fire button to send a pulse to the SCR to fire the PFN and in turn, the HEML. The HEML projectile's tip hits a target that is held by the CT. The CT consists of a table to hold the PFN and HEML, a vacuum chuck, air bearing, velocity meter and catch pot. The Target is held with the vacuum chuck awaiting impact. After impact, the air bearing allows the target to fall freely for the velocity meter to get an accurate reading. A known acceleration is determined from the known change in velocity of the target. Thus, if an accelerometer was attached to the target, the measured value can be compared to the known value.

Erik Timpson

2012-05-13T23:59:59.000Z

314

Electromagnetic anti-jam telemetry tool  

DOE Patents [OSTI]

A mud-pulse telemetry tool includes a tool housing, a motor disposed in the tool housing, and a magnetic coupling coupled to the motor and having an inner shaft and an outer shaft. The tool may also include a stator coupled to the tool housing, a restrictor disposed proximate the stator and coupled to the magnetic coupling, so that the restrictor and the stator adapted to generate selected pulses in a drilling fluid when the restrictor is selectively rotated. The tool may also include a first anti-jam magnet coupled to the too housing, and an second anti-jam magnet disposed proximate the first anti-jam magnet and coupled to the inner shaft and/or the outer shaft, wherein at least one of the first anti-jam magnet and the second anti-jam magnet is an electromagnet, and wherein the first anti-jam magnet and the second anti-jam magnet are positioned with adjacent like poles.

Ganesan, Harini (Sugar Land, TX); Mayzenberg, Nataliya (Missouri City, TX)

2008-02-12T23:59:59.000Z

315

Nucleon Structure Studies with Electromagnetic Probes  

SciTech Connect (OSTI)

Summarized in this report is the progress achieved during the period from March 1, 2008 to June 14, 2009 under contract number DE-FG02-03ER41252. This is the final technical report under this contract. The experimental work described here is part of the electromagnetic nuclear physics program of the CEBAF Large Acceptance Spectrometer (CLAS) Collaboration at the Thomas Jefferson National Accelerator Facility (Jefferson Lab) that published 17 journal articles during the period of this report. One of these journal articles reported on the results of precise measurements of the neutron magnetic form factor. I was a spokesperson on this experiment and the publication of these results is the culmination of years of effort by a small subset of the CLAS Collaboration. As usual, undergraduate students were involved in all aspects of this work. Three Union College students participated in this program during the window of this report and one presented a paper on his work at the 2009 National Conference on Undergraduate Research (NCUR22). In this report, I discuss recent progress on the measurements of the neutron magnetic form factor and describe my service work for the CLAS Collaboration.

Vineyard, Michael F.

2011-03-31T23:59:59.000Z

316

Electromagnetic waves in a polydisperse dusty plasma  

SciTech Connect (OSTI)

The properties of low-frequency electromagnetic waves in a polydisperse dusty plasma are studied. The dispersion relation for the waves propagating at an arbitrary angle to the external magnetic field is derived, with the coefficients explicitly determined by the dust-size distribution function. The dependence of wave dispersion on properties of the dust-size distribution function is analysed. It is shown that the cutoff for an oblique propagation in plasma with a wide scatter of dust sizes takes place at a much lower frequency than in a plasma with monosized dust particles. It is found that dispersion properties of a transversal magnetosonic wave mode around dustcyclotron frequencies considerably differ from those in a plasma with monosized dust. In a plasma with low mass fraction of dust particles, the dispersion is smooth without the cutoff and the resonance intrinsic for a plasma with monosized dust. Increase of the dust fraction results in splitting of the dispersion curve on to two branches. Further increase of the dust fraction leads to emergence of the third branch located between the cutoffs and restricted from the lower and higher frequencies by two resonances. The dependence of the frequencies of cutoffs and resonances on the width of the dust-size distribution, its slope and the dust mass fraction are analysed. It is shown that the transparency frequency windows in a plasma with polydisperse dust are wider for transversal elecromagnetic waves, but narrower for longitudinal or oblique waves.

Prudskikh, V. V.; Shchekinov, Yu. A. [Department of Physics, Southern Federal University, Rostov on Don 344090 (Russian Federation)] [Department of Physics, Southern Federal University, Rostov on Don 344090 (Russian Federation)

2013-10-15T23:59:59.000Z

317

Horizontal electromagnetic casting of thin metal sheets  

DOE Patents [OSTI]

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

1987-01-01T23:59:59.000Z

318

Horizontal electromagnetic casting of thin metal sheets  

DOE Patents [OSTI]

Thin metal sheets are cast by magnetically suspending molten metal deposited within a ferromagnetic yoke and between AC conducting coils and linearly displacing the magnetically levitated liquid metal while it is being cooled to form a solid metal sheet. Magnetic flux increases as the molten metal sheet moves downward and decreases as the molten metal sheet moves upward to stabilize the sheet and maintain it in equilibrium as it is linearly displaced and solidified by cooling gases. A conducting shield is electrically coupled to the molten metal sheet by means of either metal sheet engaging rollers or brushes on the solidified metal, and by means of an electrode in the vessel containing the molten metal thereby providing a return path for the eddy currents induced in the metal sheet by the AC coil generated magnetic flux. Variation in the geometry of the conducting shield allows the magnetic flux between the metal sheet and the conducting shield to be varied and the thickness in surface quality of the metal sheet to be controlled. Side guards provide lateral containment for the molten metal sheet and stabilize and shape the magnetic field while a leader sheet having electromagnetic characteristics similar to those of the metal sheet is used to start the casting process and precedes the molten metal sheet through the magnet and forms a continuous sheet therewith. The magnet may be either U-shaped with a single racetrack coil or may be rectangular with a pair of facing bedstead coils.

Hull, John R. (Hinsdale, IL); Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

1988-01-01T23:59:59.000Z

319

Electromagnetic Probes at RHIC-II  

E-Print Network [OSTI]

We summarize how future measurements of electromagnetic (e.m.) probes at the Relativistic Heavy Ion Collider (RHIC), in connection with theoretical analysis, can advance our understanding of strongly interacting matter at high energy densities and temperatures. After a brief survey of the important role that e.m. probes data have played at the Super Proton Synchrotron (SPS, CERN) and RHIC to date, we identify key physics objectives and observables that remain to be addressed to characterize the (strongly interacting) Quark-Gluon Plasma (sQGP) and associated transition properties at RHIC. These include medium modifications of vector mesons via low-mass dileptons, a temperature measurement of the hot phases via continuum radiation, as well as gamma-gamma correlations to characterize early source sizes. We outline strategies to establish microscopic matter and transition properties such as the number of degrees of freedom in the sQGP, the origin of the hadron masses and manifestations of chiral symmetry restoration, which will require accompanying but rather well-defined advances in theory. Increased experimental precision, order of magnitude higher statistics than currently achievable, as well as a detailed scan of colliding species and energies are then mandatory to achieve sufficient discrimination power in theoretical interpretations. This increased precision can be achieved with hardware upgrades to the large RHIC detectors (PHENIX and STAR) along with at least a factor of ten as increase in luminosity over the next few years as envisioned for RHIC-II.

G. David; R. Rapp; Z. Xu

2008-04-25T23:59:59.000Z

320

Binary power multiplier for electromagnetic energy  

DOE Patents [OSTI]

A technique for converting electromagnetic pulses to higher power amplitude and shorter duration, in binary multiples, splits an input pulse into two channels, and subjects the pulses in the two channels to a number of binary pulse compression operations. Each pulse compression operation entails combining the pulses in both input channels and selectively steering the combined power to one output channel during the leading half of the pulses and to the other output channel during the trailing half of the pulses, and then delaying the pulse in the first output channel by an amount equal to half the initial pulse duration. Apparatus for carrying out each of the binary multiplication operation preferably includes a four-port coupler (such as a 3 dB hybrid), which operates on power inputs at a pair of input ports by directing the combined power to either of a pair of output ports, depending on the relative phase of the inputs. Therefore, by appropriately phase coding the pulses prior to any of the pulse compression stages, the entire pulse compression (with associated binary power multiplication) can be carried out solely with passive elements.

Farkas, Zoltan D. (203 Leland Ave., Menlo Park, CA 94025)

1988-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

Development of an electromagnetically actuated mercury microvalve  

SciTech Connect (OSTI)

The development of microscale fluid handling components has been recognized as a crucial element in the design of microscale chemical detection systems. Recently, work has been undertaken at Sandia National Laboratories to construct a valve that uses a small mercury droplet to control the flow of gas through capillary passages. Electromagnetic forces that are provided by small permanent magnets and a current supply are used to drive the mercury into position. Driving the mercury droplet into a tapered passage halts gas flow through a capillary, while surface tension forces prevent the mercury from passing through the passage. Models have been developed to describe the movement of the mercury droplet and the sealing of the gas passage, and millimeter-scale units have been tested to explore design options. Predictions from the model show that a valve with 10 micron sized features can seal against pressures up to 1.5 atmospheres. Experiments have highlighted the promise of mercury valves and demonstrated problems that can arise from contamination of the mercury.

Adkins, D.R.; Wong, C.C.

1998-08-01T23:59:59.000Z

322

Effects of Electromagnetic Field on Energy Density Inhomogeneity in Self-Gravitating Fluids  

E-Print Network [OSTI]

This paper is devoted to study the effects of electromagnetic field on the energy density inhomogeneity in the relativistic self-gravitating fluids for spherically symmetric spacetime. Two important equations of the Weyl tensor are formulated which help to analyze the energy density inhomogeneity in this scenario. We investigate two types of fluids, i.e., non-dissipative and dissipative. The non-dissipative fluid further includes dust, locally isotropic, and locally anisotropic charged fluids. We explore the effects of different factors on energy density inhomogeneity in all these cases, in particular, the effect of charge.

M. Sharif; Neelum Bashir

2012-09-25T23:59:59.000Z

323

Propagation of terahertz electromagnetic wave in plasma with inhomogeneous collision frequency  

SciTech Connect (OSTI)

In this paper, we investigate the absorption spectra of terahertz electromagnetic wave in plasma with inhomogeneous collision frequency. Profiles are introduced to describe the non-uniformity of collision frequency. It is interesting to find that when the plasma is collision frequency inhomogeneous, the absorption spectrum would decreases faster than that in uniform plasma. And the rate of decreasing would be different when the profile changes. Two parameters are set up to predict how the profiles affect the absorption spectra. Furthermore, the effects of electron density are also considered.

Tian, Yuan; Han, YiPing; Ling, YingJie [School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071 (China)] [School of Physics and Optoelectronic Engineering, Xidian University, Xi'an 710071 (China); Ai, Xia [National Laboratory of Science and Technology on Antennas and Microwaves Xidian University, Xi'an 710071 (China)] [National Laboratory of Science and Technology on Antennas and Microwaves Xidian University, Xi'an 710071 (China)

2014-02-15T23:59:59.000Z

324

Extinction theorem and propagation of electromagnetic waves between two semi-infinite anisotropic magnetoelectric materials  

E-Print Network [OSTI]

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.

Weixing Shu; Zhongzhou Ren; Hailu Luo; Fei Li; Qin Wu

2006-10-11T23:59:59.000Z

325

Unification of Electromagnetism and Gravitation in the Framework of General Geometry  

E-Print Network [OSTI]

A new geometry, called General geometry, is constructed. It is proven that its the most simplest special case is geometry underlying Electromagnetism. Another special case is Riemannian geometry. Action for electromagnetic field and Maxwell equations are derived from curvature function of geometry underlying Electromagnetism. It is shown that equation of motion for a particle interacting with electromagnetic field coincides exactly with equation for geodesics of geometry underlying Electromagnetism. It is also shown that Electromagnetism can not be geometrized in the framework of Riemannian geometry. Using General Geometry we propose a unified model of electromagnetism and gravitation which reproduces Electromagnetism and Gravitation and predicts that electromagnetic field is a source for gravitational field. This theory is formulated in four dimensional spacetime and does not contain additional fields.

Shervgi Shahverdiyev

2005-07-05T23:59:59.000Z

326

An investigation of the depolarization of backscattered electromagnetic waves using a lidar polarimeter  

E-Print Network [OSTI]

of the samples was varied from a very rough to a moderately rough surface. Using these targets, polarized and depolarized backscatter measurements were recorded using both horizon- tal and vertical transmit polarization for angles of in- cidence between 0...' . . . . . . . . . . . 48 III -3 III-4 II I- 5 III-6 Intensity pattern for p /p a s Intensity pattern for p /p a s Intensity pattern for p /p a s 2. 0 x 10 1. 0 x 10 2. 62 x 10 Experimental arrangement for collimated beam experiment 49 50 51 53 III- 7...

Wilhelmi, Gary Joe

2012-06-07T23:59:59.000Z

327

Power Drive Investigation by Spectral Analysis of the Electromagnetic Field Emitted by the  

E-Print Network [OSTI]

, through the widely spread Partial Element Equivalent Circuit (PEEC) modelling of the surfacic conductor diagnosis, optimal use and quality management. However, diagnosis is, until today, mainly based on vibration

Boyer, Edmond

328

Pair and Impar, Even and Odd Form Fields and Electromagnetism  

E-Print Network [OSTI]

In this paper after reviewing the Schouten and de Rham definition of impair and pair differential form fields (not to be confused with differential form fields of even and odd grades) we prove that in a relativistic spacetime it is possible (despite claims in contrary) to coherently formulate electromagnetism (and we believe any other physical theory) using only pair form fields or, if one wishes, using pair and impair form fields together, in an appropriate way. Those two distinct descriptions involve only a mathematical choice and do not seem to lead to any observable physical consequence if due care is taken. Moreover, we show in details that a formulation of electromagnetic theory in the Clifford bundle formalism of differential forms where the two Maxwell equations of the so called free metric approach becomes a single equation is compatible with both formulations of electromagnetism just mentioned above. Moreover we derive directly from Maxwell equation the density of force (coupling of the electromagnetic field with the charge current) that is a postulate in the free metric approach to electromagnetism. We recall also a formulation of the engineering version of Maxwell equations using electric and magnetic fields as objects of the same nature, i.e., without using polar and axial vectors.

Roldao da Rocha; Waldyr A. Rodrigues Jr

2009-08-13T23:59:59.000Z

329

Lattice p-Form Electromagnetism and Chain Field Theory  

E-Print Network [OSTI]

Since Wilson's work on lattice gauge theory in the 1970s, discrete versions of field theories have played a vital role in fundamental physics. But there is recent interest in certain higher dimensional analogues of gauge theory, such as p-form electromagnetism, including the Kalb-Ramond field in string theory, and its nonabelian generalizations. It is desirable to discretize such `higher gauge theories' in a way analogous to lattice gauge theory, but with the fundamental geometric structures in the discretization boosted in dimension. As a step toward studying discrete versions of more general higher gauge theories, we consider the case of p-form electromagnetism. We show that discrete p-form electromagnetism admits a simple algebraic description in terms of chain complexes of abelian groups. Moreover, the model allows discrete spacetimes with quite general geometry, in contrast to the regular cubical lattices usually associated with lattice gauge theory. After constructing a suitable model of discrete spacetime for p-form electromagnetism, we quantize the theory using the Euclidean path integral formalism. The main result is a description of p-form electromagnetism as a `chain field theory' -- a theory analogous to topological quantum field theory, but with chain complexes replacing manifolds. This, in particular, gives a notion of time evolution from one `spacelike slice' of discrete spacetime to another.

Derek K. Wise

2005-10-08T23:59:59.000Z

330

Transverse electromagnetic horn antenna with resistively-loaded exterior surfaces  

DOE Patents [OSTI]

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.

Aurand, John F. (Edgewood, NM)

1999-01-01T23:59:59.000Z

331

The momentum of an electromagnetic wave inside a dielectric  

SciTech Connect (OSTI)

The problem of assigning a momentum to an electromagnetic wave packet propagating inside an insulator has become known under the name of the AbrahamMinkowski 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 Snells law from the conservation of the Abraham momentum. We show how to deal with the electric field discontinuity at the dielectric boundary.

Testa, Massimo, E-mail: massimo.testa@roma1.infn.it

2013-09-15T23:59:59.000Z

332

A Continuous Field Theory of Matter and Electromagnetism  

E-Print Network [OSTI]

A continuous field theory of matter and electromagnetism is developed. The starting point of the theory is the classical Maxwell equations which are directly tied to the Riemann-Christoffel curvature tensor. This is done through the derivatives of the Maxwell tensor which are equated to a vector field contracted with the curvature tensor. The electromagnetic portion of the theory is shown to be equivalent to the classical Maxwell equations with the addition of a hidden variable. Because the proposed equations describing electromagnetism and matter differ from the classical Maxwell-Einstein equations, their ability to describe classical physics is shown for several situations by direct calculation. The inclusion of antimatter and the possibility of particle-like solutions exhibiting both quantized charge and mass are discussed.

Raymond J. Beach

2012-08-31T23:59:59.000Z

333

Method for imaging with low frequency electromagnetic fields  

DOE Patents [OSTI]

A method is described for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The travel times corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter [alpha] for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography. 13 figures.

Lee, K.H.; Xie, G.Q.

1994-12-13T23:59:59.000Z

334

Method for imaging with low frequency electromagnetic fields  

DOE Patents [OSTI]

A method for imaging with low frequency electromagnetic fields, and for interpreting the electromagnetic data using ray tomography, in order to determine the earth conductivity with high accuracy and resolution. The imaging method includes the steps of placing one or more transmitters, at various positions in a plurality of transmitter holes, and placing a plurality of receivers in a plurality of receiver holes. The transmitters generate electromagnetic signals which diffuse through a medium, such as earth, toward the receivers. The measured diffusion field data H is then transformed into wavefield data U. The traveltimes corresponding to the wavefield data U, are then obtained, by charting the wavefield data U, using a different regularization parameter .alpha. for each transform. The desired property of the medium, such as conductivity, is then derived from the velocity, which in turn is constructed from the wavefield data U using ray tomography.

Lee, Ki H. (Lafayette, CA); Xie, Gan Q. (Berkeley, CA)

1994-01-01T23:59:59.000Z

335

Graded pitch electromagnetic pump for thin strip metal casting systems  

DOE Patents [OSTI]

A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel. 4 figs.

Kuznetsov, S.B.

1986-04-01T23:59:59.000Z

336

Characteristics of electromagnetic interference generated during discharge of Mylar samples  

SciTech Connect (OSTI)

This paper discusses the measurements of the electromagnetic interference (EMI) generated during discharges of Mylar samples. The two components of EMI, the conducted emission and the radiated emission, are characterized by the replacement current and the radiated RF spectrum respectively. The measured radiated RF spectra reveal important information on the source of the electromagnetic radiation. The possible sources are the replacement current pulse and the discharged generated plasma. The scaling of the amplitudes of the EMI, as a function of the area of the test sample, is also discussed.

Leung, P.L.

1984-12-01T23:59:59.000Z

337

Graded pitch electromagnetic pump for thin strip metal casting systems  

DOE Patents [OSTI]

A metal strip casing system is provided with an electromagnetic pump which includes a pair of primary blocks having a graded pole pitch, polyphase ac winding and being arranged on opposite sides of a movable heat sink. A nozzle is provided for depositing liquid metal on the heat sink such that the resulting metal strip and heat sink combination is subjected to a longitudinal electromagnetic field which increases in wavelength in the direction of travel of the heat sink, thereby subjecting the metal and heat sink to a longitudinal force having a magnitude which increases in the direction of travel.

Kuznetsov, Stephen B. (Pittsburgh, PA)

1986-01-01T23:59:59.000Z

338

Giant Electromagnet Move at Brookhaven Lab, June 22, 2013  

SciTech Connect (OSTI)

On Saturday, June 22, 2013, a 50-foot-wide, circular electromagnet began its 3,200-mile land and sea voyage from Brookhaven National Laboratory in New York to a new home at Fermilab in Illinois. There, scientists will use it to study the properties of muons, subatomic particles that live only 2.2 millionths of a second, and the results could open the door to new realms of particle physics. In the first part of the move, Emmert International and a team of Fermilab and Brookhaven Lab scientists and engineers transported the electromagnet across the Brookhaven Lab site to a staging area by its main gate.

None

2013-06-22T23:59:59.000Z

339

Beam dynamics studies for transverse electromagnetic mode type rf deflectors  

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

We have performed three-dimensional simulations of beam dynamics for transverse electromagnetic mode (TEM) type rf deflectors: normal and superconducting. The compact size of these cavities as compared to the conventional TM110 type structures is more attractive particularly at low frequency. Highly concentrated electromagnetic fields between the parallel bars provide strong electrical stability to the beam for any mechanical disturbance. An array of six 2-cell normal conducting cavities or a single cell superconducting structure is enough to produce the required vertical displacement at the target point. Both the normal and superconducting structures show very small emittance dilution due to the vertical kick of the beam.

Ahmed, Shahid; Krafft, Geoffrey A.; Deitrick, Kirsten; De Silva, Subashini U.; Delayen, Jean R.; Spata, Mike; Tiefenback, Michael; Hofler, Alicia; Beard, Kevin

2012-02-01T23:59:59.000Z

340

Reverse Time Migration for Extended Obstacles: Electromagnetic Waves  

E-Print Network [OSTI]

We propose a new single frequency reverse time migration (RTM) algorithm for imaging extended targets using electromagnetic waves. The imaging functional is defined as the imaginary part of the cross-correlation of the Green function for Helmholtz equation and the back-propagated electromagnetic field. The resolution of our RTM method for both penetrable and non-penetrable extended targets is studied by virtue of Helmholtz-Kirchhoff identity for the time-harmonic Maxwell equation. The analysis implies that our imaging functional is always positive and thus may have better stability properties. Numerical examples are provided to demonstrate the powerful imaging quality and confirm our theoretical results.

Junqing Chen; Zhiming Chen; Guanghui Huang

2014-06-10T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Electromagnetic leptogenesis at the TeV scale  

E-Print Network [OSTI]

We construct an explicit model implementing electromagnetic leptogenesis. In a simple extension of the Standard Model, a discrete symmetry forbids the usual decays of the right-handed neutrinos, while allowing for an effective coupling between the left-handed and right-handed neutrinos through the electromagnetic dipole moment. This generates correct leptogenesis with resonant enhancement and also the required neutrino mass via a TeV scale seesaw mechanism. The model is consistent with low energy phenomenology and would have distinct signals in the next generation colliders, and, perhaps even the LHC.

Debajyoti Choudhury; Namit Mahajan; Sudhanwa Patra; Utpal Sarkar

2011-04-11T23:59:59.000Z

342

Electromagnetic nucleon form factors in instant and point form  

E-Print Network [OSTI]

We present a study of the electromagnetic structure of the nucleons with constituent quark models in the framework of relativistic quantum mechanics. In particular, we address the construction of spectator-model currents in the instant and point forms. Corresponding results for the elastic nucleon electromagnetic form factors as well as charge radii and magnetic moments are presented. We also compare results obtained by different realistic nucleon wave functions stemming from alternative constituent quark models. Finally, we discuss the theoretical uncertainties that reside in the construction of spectator-model transition operators.

T. Melde; K. Berger; L. Canton; W. Plessas; R. F. Wagenbrunn

2007-09-30T23:59:59.000Z

343

Electromagnetic Field Quantization in Time-Dependent Dielectric Media  

E-Print Network [OSTI]

We present a Gupta-Bleuler quantization scheme for the electromagnetic field in time-dependent dielectric media. Starting from the Maxwell equations, a generalization of the Lorentz gauge condition adapted to time varying dielectrics is derived. Using this gauge, a Gupta-Bleuler approach to quantize all polarizations of the radiation field and the corresponding constraint condition are introduced. This new approach is different from the quantized electromagnetic field in vacuum in the sense that here the contributions of unphysical photons cannot be thoroughly eliminated, which further lead to a surface charge density. Finally, a discussion of potential experimental tests and possible implication is also made.

Xiao-Min Bei; Zhong-Zhu Liu

2011-04-18T23:59:59.000Z

344

Electromagnetic field quantization in a linear dielectric medium  

E-Print Network [OSTI]

By modeling a dielectric medium with two independent reservoirs, i.e., electric and magnetic reservoirs, the electromagnetic field is quantized in a linear dielectric medium consistently. A Hamiltonian is proposed from which using the Heisenberg equations, not only the Maxwell equations but also the structural equations can be obtained. Using the Laplace transformation, the wave equation for the electromagnetic vector potential is solved in the case of a homogeneous dielectric medium. Some examples are considered showing the applicability of the model to both absorptive and nonabsorptive dielectrics.

F. Kheirandish; M. Amooshahi

2005-11-13T23:59:59.000Z

345

Electromagnetically Induced Transparency from a Single Atom in Free Space  

E-Print Network [OSTI]

We report an absorption spectroscopy experiment and the observation of electromagnetically induced transparency from a single trapped atom. We focus a weak and narrowband Gaussian light beam onto an optically cooled Barium ion using a high numerical aperture lens. Extinction of this beam is observed with measured values of up to 1.3 %. We demonstrate electromagnetically induced transparency of the ion by tuning a strong control beam over a two-photon resonance in a three-level lambda-type system. The probe beam extinction is inhibited by more than 75 % due to population trapping.

L. Slodicka; G. Hetet; S. Gerber; M. Hennrich; R. Blatt

2010-05-18T23:59:59.000Z

346

Analog Electromagnetism in a Symmetrized $^3$He-A  

E-Print Network [OSTI]

We derive a low temperature effective action for the order parameter in a symmetrized phase A of helium 3, where the Fermi velocity equals the transversal velocity of low energy fermionic quasiparticles. The effective action has a form of the electromagnetic action. This analog electromagnetism is a part of the program to derive analog gravity and the standard model as a low energy effective theory in a condensed matter system. For the analog gauge field to satisfy the Maxwell equations interactions in $^3$He require special tuning that leads to the symmetric case.

Jacek Dziarmaga

2001-12-18T23:59:59.000Z

347

Statistics of the electromagnetic response of a chaotic reverberation chamber  

E-Print Network [OSTI]

This article presents a study of the electromagnetic response of a chaotic reverberation chamber (RC) in the presence of losses. By means of simulations and of experiments, the fluctuations in the maxima of the field obtained in a conventional mode-stirred RC are compared with those in a chaotic RC in the neighborhood of the Lowest Useable Frequency (LUF). The present work illustrates that the universal spectral and spatial statistical properties of chaotic RCs allow to meet more adequately the criteria required by the Standard IEC 61000-4-21 to perform tests of electromagnetic compatibility.

J. -B. Gros; U. Kuhl; O. Legrand; F. Mortessagne; O. Picon; E. Richalot

2014-09-20T23:59:59.000Z

348

Spectrally isomorphic Dirac systems: graphene in electromagnetic field  

E-Print Network [OSTI]

We construct the new one-dimensional Dirac Hamiltonians that are spectrally isomorphic (not isospectral) with the known exactly solvable models. Explicit formulas for their spectra and eigenstates are provided. The operators are utilized for description of Dirac fermions in graphene in presence of an inhomogeneous electromagnetic field. We discuss explicit, physically relevant, examples of spectrally isomorphic systems with both non-periodic and periodic electromagnetic barriers. In the latter case, spectrally isomorphic two- and three-gap systems associated with the Ablowitz-Kaup-Newell-Segur hierarchy are considered.

Jakubsky, Vit

2014-01-01T23:59:59.000Z

349

Improved Magnetic Fusion Energy Economics via Massive Resistive Electromagnets  

SciTech Connect (OSTI)

Abandoning superconductors for magnetic fusion reactors and instead using resistive magnet designs based on cheap copper or aluminum conductor material operating at "room temperature" (300 K) can reduce the capital cost per unit fusion power and simplify plant operations. By increasing unit size well beyond that of present magnetic fusion energy conceptual designs using superconducting electromagnets, the recirculating power fraction needed to operate resistive electromagnets can be made as close to zero as needed for economy without requiring superconductors. Other advantages of larger fusion plant size, such as very long inductively driven pulses, may also help reduce the cost per unit fusion power.

Woolley, R.D.

1998-08-19T23:59:59.000Z

350

Electromagnetic Casimir densities for a wedge with a coaxial cylindrical shell  

E-Print Network [OSTI]

Vacuum expectation values of the field square and the energy-momentum tensor for the electromagnetic field are investigated for the geometry of a wedge with a coaxal cylindrical boundary. All boundaries are assumed to be perfectly conducting and both regions inside and outside the shell are considered. By using the generalized Abel-Plana formula, the vacuum expectation values are presented in the form of the sum of two terms. The first one corresponds to the geometry of the wedge without the cylindrical shell and the second term is induced by the presence of the shell. The vacuum energy density induced by the shell is negative for the interior region and is positive for the exterior region. The asymptotic behavior of the vacuum expectation values are investigated in various limiting cases. It is shown that the vacuum forces acting on the wedge sides due to the presence of the cylindrical boundary are always attractive.

A. A. Saharian

2007-04-15T23:59:59.000Z

351

Merging and splitting of clusters in the electromagnetic calorimeter of the KLOE detector  

E-Print Network [OSTI]

The work was carried out in the framework of the KLOE collaboration studying the decays of the phi meson produced in the DAFNE accelerator in the collisions of electron and positron. The main aim of this thesis was investigation of the influence of the merging and splitting of clusters in decays with the high multiplicity of gamma quanta, which are at most biased by these effects. For this aim we implemented the full geometry and realistic material composition of the barrel electromagnetic calorimeter in FLUKA package. The prepared Monte Carlo based simulation program permits to achieve a fast generation of the detector response separately for each interested reaction. The program was used to study the reconstruction efficiency with the KLOE clustering algorithm as a function of the photocathode quantum efficiency. It was also used to investigate merging and splitting probabilities as a function of the quantum efficiency. The conducted studies indicated that the increase of quantum efficiency does not improve...

Zdebik, Jaroslaw

2008-01-01T23:59:59.000Z

352

Early detection of critical material degradation by means of electromagnetic multi-parametric NDE  

SciTech Connect (OSTI)

With an increasing number of power plants operated in excess of their original design service life an early recognition of critical material degradation in components will gain importance. Many years of reactor safety research allowed for the identification and development of electromagnetic NDE methods which detect precursors of imminent damage with high sensitivity, at elevated temperatures and in a radiation environment. Regarding low-alloy heat-resistant steel grade WB 36 (1.6368, 15NiCuMoNb5), effects of thermal and thermo-mechanical aging on mechanical-technological properties and several micromagnetic parameters have been thoroughly studied. In particular knowledge regarding the process of copper precipitation and its acceleration under thermo-mechanical load has been enhanced. Whilst the Cu-rich WB 36 steel is an excellent model material to study and understand aging effects related to neutron radiation without the challenge of handling radioactive specimens in a hot cell, actually neutron-irradiated reactor pressure vessel materials were investigated as well. The neutron fluence experienced and the resulting shift of the ductile-brittle transition temperature were determined electromagnetically, and it was shown that weld and base material can be distinguished from the cladded side of the RPV wall. Low-cycle fatigue of the austenitic stainless steel AISI 347 (1.4550, X6CrNiNb18-10) has been characterized with electromagnetic acoustic transducers (EMATs) at temperatures of up to 300 C. Time-of-flight and amplitude of the transmitted ultrasound signal were evaluated against the number of load cycles applied and observed as an indication of the imminent material failure significantly earlier than monitoring stresses or strains.

Szielasko, Klaus; Tschuncky, Ralf; Rabung, Madalina; Altpeter, Iris; Dobmann, Gerd [Fraunhofer Institute for Nondestructive Testing (IZFP), Campus E3 1, 66123 Saarbrcken (Germany); Seiler, Georg; Herrmann, Hans-Georg; Boller, Christian [Fraunhofer Institute for Nondestructive Testing (IZFP), Campus E3 1, 66123 Saarbrcken, Germany and Saarland University, Chair of NDT and Quality Assurance, Campus E3 1, 66123 Saarbrcken (Germany)

2014-02-18T23:59:59.000Z

353

Laboratory Studies of the Short-term Responses of Freshwater Fish to Electromagnetic Fields  

SciTech Connect (OSTI)

Hydrokinetic energy technologies are being proposed as an environmentally preferred means of generating electricity from river and tidal currents. Among the potential issues that must be investigated in order to resolve environmental concerns are the effects on aquatic organisms of electromagnetic fields created by underwater generators and transmission cables. The behavioral responses of common freshwater fishes to static and variable electromagnetic fields (EMF) that may be emitted by hydrokinetic projects were evaluated in laboratory experiments. Various fish species were exposed to either static (DC) EMF fields created by a permanent bar magnet or variable (AC) EMF fields created by a switched electromagnet for 48 h, fish locations were recorded with a digital imaging system, and changes in activity level and distribution relative to the magnet position were quantified at 5-min intervals. Experiments with fathead minnows, redear sunfish, striped bass, lake sturgeon, and channel catfish produced mixed results. Except for fathead minnows there was no effect on activity level. Only redear sunfish and channel catfish exhibited a change in distribution relative to the position of the magnet with an apparent attraction to the EMF source. In separate experiments, rapid behavioral responses of paddlefish and lake sturgeon to onset of the AC field were recorded with high-speed video. Paddlefish did not react to a variable, 60-Hz magnetic field like that which would be emitted by an AC generator or cable, but lake sturgeon consistently responded to the variable, AC-generated magnetic field with a variety of altered swimming behaviors. These results will be useful for determining under what circumstances cables or generators need to be positioned to minimize interactions with sensitive species.

Bevelhimer, Mark S [ORNL; Cada, Glenn F [ORNL; Fortner, Allison M [ORNL; Schweizer, Peter E [ORNL; Riemer, Kristina P [ORNL

2013-01-01T23:59:59.000Z

354

Recoil polarization measurements of the proton electromagnetic form factor ratio to high momentum transfer  

E-Print Network [OSTI]

The electromagnetic form factors of the nucleon characterize the effect of its internal structure on its response to an electromagnetic probe as studied in elastic electronnucleon scattering. These form factors are functions ...

Puckett, Andrew James Ruehe

2010-01-01T23:59:59.000Z

355

Electromagnetic compatibility and electrical noise control for the DOE Hanford site  

SciTech Connect (OSTI)

This document was written by MDM Corp., Richland, WA to provide recommended electromagnetic interference and electromagnetic compatibility for double shell tank and waste feed delivery project requirements. Minimally acceptable requirements for facility design are suggested.

DEICHELBOHRER, P.

2003-02-26T23:59:59.000Z

356

Recording speech articulation in dialogue: Evaluating a synchronized double electromagnetic articulography setup  

E-Print Network [OSTI]

is the severity of electromagnetic interference between the two machines. Our results suggest that the synchronization method used yields an accuracy of approximately 1 ms. Electromagnetic interference was derived

Edinburgh, University of

357

Electromagnetic signatures of far-field gravitational radiation in the 1+3 approach  

E-Print Network [OSTI]

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.

Alvin J. K. Chua; Priscilla Caizares; Jonathan R. Gair

2014-12-06T23:59:59.000Z

358

Electromagnetic space-time crystals. III. Dispersion relations for partial solutions  

E-Print Network [OSTI]

Partial solutions of the Dirac equation describing an electron motion in electromagnetic crystals created by plane waves with linear and circular polarizations are treated. It is shown that the electromagnetic crystal formed by circularly polarized waves possesses the spin birefringence.

G. N. Borzdov

2014-10-21T23:59:59.000Z

359

Cryogenic heat pipe for cooling high temperature superconductors with application to Electromagnetic Formation Flight Satellites  

E-Print Network [OSTI]

An emerging method of propellant-less formation flight propulsion is the use of electromagnets coupled with reaction wheels. This technique is called Electromagnetic Formation Flight (EMFF). In order to create a large ...

Kwon, Daniel W., 1980-

2009-01-01T23:59:59.000Z

360

Rayleigh-Taylor-Induced electromagnetic fields in laser-produced plasmas  

E-Print Network [OSTI]

Spontaneous electromagnetic fields can be important to the dynamic evolution of a plasma by directing heat flow as well as providing additional pressures on the conducting fluids through the Lorentz force. Electromagnetic ...

Manuel, Mario John-Errol

2013-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD  

SciTech Connect (OSTI)

The ATLAS Electromagnetic (EM) calorimeter (EMCAL) Front End Board (FEB) will be located in custom-designed enclosures solidly connected to the feedtroughs. It is a complex mixed signal board which includes the preamplifier, shaper, switched capacitor array analog memory unit (SCA), analog to digital conversion, serialization of the data and related control logic. It will be described in detail elsewhere in these proceedings. The electromagnetic interference (either pick-up from the on board digital activity, from power supply ripple or from external sources) which affects coherently large groups of channels (coherent noise) is of particular concern in calorimetry and it has been studied in detail.

CHASE,B.CITTERIO,M.LANNI,F.MAKOWIECKI,D.RADEKA,S.RESCIA,S.TAKAI,H.ET AL.

1999-09-20T23:59:59.000Z

362

CHARACTERIZATION OF THE COHERENT NOISE, ELECTROMAGNETIC COMPATIBILITY AND ELECTROMAGNETIC INTERFERENCE OF THE ATLAS EM CALORIMETER FRONT END BOARD  

SciTech Connect (OSTI)

The ATLAS Electromagnetic (EM) calorimeter (EMCAL) Front End Board (FEB) will be located in custom-designed enclosures solidly connected to the feedtroughs. It is a complex mixed signal board which includes the preamplifier, shaper, switched capacitor array analog memory unit (SCA), analog to digital conversion, serialization of the data and related control logic. It will be described in detail elsewhere in these proceedings. The electromagnetic interference (either pick-up from the on board digital activity, from power supply ripple or from external sources) which affects coherently large groups of channels (coherent noise) is of particular concern in calorimetry and it has been studied in detail.

CHASE,R.L.; CITTERIO,M.; LANNI,F.; MAKOWIECKI,D.; RADEKA,V.; RESCIA,S.; TAKAI,H.; BAN,J.; PARSONS,J.; SIPPACH,W.

2000-09-20T23:59:59.000Z

363

Noise Reduction and Design Methodology in Mixed-Signal Systems with Alternating Impedance Electromagnetic Bandgap (AI-EBG)  

E-Print Network [OSTI]

integrity as well as electromagnetic interference (EMI). In this paper, excellent noise suppression with AI, electromagnetic interference. I. INTRODUCTION The integration of wireless technologies in handset and mobile

Swaminathan, Madhavan

364

Probabilistic methods applied to 2D electromagnetic numerical dosimetry  

E-Print Network [OSTI]

the number of realizations. When the modeling of the 3D interaction between the human body and a cellphoneProbabilistic methods applied to 2D electromagnetic numerical dosimetry D. Voyer F. Musy L. Nicolas dosimetry problems in order to take into account the variability of the input parameters. Methodology

Paris-Sud XI, Université de

365

Measurement of Electromagnetic Parameters and FDTD Modeling of Ferrite Cores  

E-Print Network [OSTI]

Measurement of Electromagnetic Parameters and FDTD Modeling of Ferrite Cores Jianfeng Xu #1 products based on magneto-dielectric (ferrite) materials with desirable frequency responses that satisfy simulation tool that could deal with frequency- dispersive materials. An example of a ferrite material

Koledintseva, Marina Y.

366

Understanding stable levitation of superconductors from intermediate electromagnetics  

E-Print Network [OSTI]

related to magnetic flux conservation and minimum energy losses. II. BASIC SUPERCONDUCTIVITY for electromagnetic energy related quantities. Comprehensible illustrations, based on the calculated lines of magnetic a superconductor (or viceversa) is related to flux expulsion. One may even use the standard image technique

Majós, Antonio Badía

367

Interactions of hadrons in the CALICE silicon tungsten electromagnetic calorimeter  

E-Print Network [OSTI]

The CALICE collaboration develops prototypes for highly granular calorimeters for detectors at a future linear electron positron collider. The highly granular electromagnetic calorimeter prototype was tested in particle beams. We present the study of the interactions of hadrons in this prototype.

Roman Pschl; for the CALICE Collaboration

2012-03-07T23:59:59.000Z

368

CONTROL ORIENTATED SYNTHESIS OF ELECTROMAGNETIC SHUNT IMPEDANCES FOR  

E-Print Network [OSTI]

a mass-spring-damper as a mechanical filter. Active isolation control systems typically include to the terminals of an electromagnetic coil, the rela- tive mechanical velocity between the coil and magnet can xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx mx dk y (a) (b) Fig. 2. Simple-mass-spring-damper isolation system: (a) unforced and (b) forced

Fleming, Andrew J.

369

Electromagnetic Generators for Portable Power Applications Matthew Kurt Senesky  

E-Print Network [OSTI]

or turbines paired with electrical generators. Producing such a system to run efficiently on the milli to power tools to electric vehicle drives to wind power generation -- that would benefit from highElectromagnetic Generators for Portable Power Applications by Matthew Kurt Senesky B.A. (Dartmouth

Sanders, Seth

370

Spacetime algebra as a powerful tool for electromagnetism  

E-Print Network [OSTI]

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.

Justin Dressel; Konstantin Y. Bliokh; Franco Nori

2014-12-03T23:59:59.000Z

371

Weak-electromagnetic interference in polarized eD scattering  

SciTech Connect (OSTI)

Observation of parity non-conservation in deep-inelastic scattering of polarized electrons from deuterium was reported in an experiment at SLAC in 1978. The events at SLAC and elsewhere leading to the successful search for parity non-conservation in the electromagnetic processes are described.

Prescott, C.Y.

1992-09-01T23:59:59.000Z

372

Electromagnetically and Thermally Driven Flow Phenomena in Electroslag Welding  

E-Print Network [OSTI]

) Electromagnetically and Thermally Driven Flow Phenomena in Electroslag Welding A. H. DILAWARI, J for the Electroslag Welding Process. In the formulation, allowance has been made {or both etee- tromagnetic and b in the use of electroslag welding (ESW), particularly for the construction of thick walled pressure vessels

Eagar, Thomas W.

373

Electromagnetic pump stator frame having power crossover struts  

DOE Patents [OSTI]

A stator frame for an electromagnetic pump includes a casing joined to a hub by a plurality of circumferentially spaced apart struts. At least one electrically insulated power crossover lead extends through the hub, through a crossover one of the struts, and through the casing for carrying electrical current therethrough.

Fanning, Alan W. (San Jose, CA); Olich, Eugene E. (Aptos, CA)

1995-01-01T23:59:59.000Z

374

1D subsurface electromagnetic fields excited by energized steel casing  

E-Print Network [OSTI]

1D subsurface electromagnetic fields excited by energized steel casing Wei Yang1 , Carlos Torres the possibility of enabling steel-cased wells as galvanic sources to detect and quantify spatial variations of electrical conductivity in the subsurface. The study assumes a vertical steel-cased well that penetrates

Torres-Verdín, Carlos

375

Practical Electromagnetic Template Attack on Pierre-Alain Fouque1  

E-Print Network [OSTI]

Practical Electromagnetic Template Attack on HMAC Pierre-Alain Fouque1 , Gaëtan Leurent1 , Denis efficient side channel attack against HMAC. Our attack assumes the presence of a side channel that reveals and can configure it, the attack recovers the secret key by monitoring a single execution of HMAC- SHA-1

Paris-Sud XI, Université de

376

ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD  

E-Print Network [OSTI]

ELECTROMAGNETIC RADIATION FROM A STRONG DC ELECTRIC FIELD Manuel Gudel 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

Guedel, Manuel

377

Behavior of Electric Current Subjected to ELF Electromagnetic Radiation  

E-Print Network [OSTI]

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.

Fran De Aquino

2002-10-05T23:59:59.000Z

378

Soft Tempest: Hidden Data Transmission Using Electromagnetic Emanations  

E-Print Network [OSTI]

- ernment programme aimed at attacking the problem, the electromagnetic broad- cast of data has been to join the European Economic Community, and the Prime Minister was worried that French president De Gaulle would block Britain's entry. He therefore asked the intelligence community to determine the French

Kuhn, Markus

379

Construction, assembly and tests of the ATLAS electromagnetic barrel calorimeter  

E-Print Network [OSTI]

The construction and assembly of the two half barrels of the ATLAS central electromagnetic calorimeter and their insertion into the barrel cryostat are described. The results of the qualification tests of the calorimeter before installation in the LHC ATLAS pit are given.

Aubert, B; Colas, Jacques; Delebecque, P; Di Ciaccio, L; El-Kacimi, M; Ghez, P; Girard, C; Gouanre, M; Goujdami, D; Jrmie, A; Jzquel, S; Lafaye, R; Massol, N; Perrodo, P; Przysiezniak, H; Sauvage, G; Thion, J; Wingerter-Seez, I; Zitoun, R; Zolnierowski, Y; Alforque, R; Chen, H; Farrell, J; Gordon, H; Grandinetti, R; Hackenburg, R W; Hoffmann, A; Kierstead, J A; Khler, J; Lanni, F; Lissauer, D; Ma, H; Makowiecki, D S; Mller, T; Norton, S; Radeka, V; Rahm, David Charles; Rehak, M; Rajagopalan, S; Rescia, S; Sexton, K; Sondericker, J; Stumer, I; Takai, H; Belymam, A; Benchekroun, D; Driouichi, C; Hoummada, A; Hakimi, M; Knee, Michael; Stroynowski, R; Wakeland, B; Datskov, V I; Drobin, V; Aleksa, Martin; Bremer, J; Carli, T; Chalifour, M; Chevalley, J L; Djama, F; Ema, L; Fabre, C; Fassnacht, P; Gianotti, F; Gonidec, A; Hansen, J B; Hervs, L; Hott, T; Lacaste, C; Marin, C P; Pailler, P; Pleskatch, A; Sauvagey, D; Vandoni, Giovanna; Vuillemin, V; Wilkens, H; Albrand, S; Belhorma, B; Collot, J; de Saintignon, P; Dzahini, D; Ferrari, A; Fulachier, J; Gallin-Martel, M L; Hostachy, J Y; Laborie, G; Ledroit-Guillon, F; Martin, P; Muraz, J F; Ohlsson-Malek, F; Saboumazrag, S; Viret, S; Othegraven, R; Zeitnitz, C; Banfi, D; Carminati, L; Cavalli, D; Citterio, M; Costa, G; Delmastro, M; Fanti, M; Mandelli, L; Mazzanti, M; Tartarelli, F; Aug, E; Baffioni, S; Bonis, J; Bonivento, W; Bourdarios, C; de La Taille, C; Fayard, L; Fournier, D; Guilhem, G; Imbert, P; Iconomidou-Fayard, L; Le Meur, G; Mencik, M; Noppe, J M; Parrour, G; Puzo, P; Rousseau, D; Schaffer, A C; Seguin-Moreau, N; Serin, L; Unal, G; Veillet, J J; Wicek, F; Zerwas, D; Astesan, F; Bertoli, W; Canton, B; Fleuret, F; Imbault, D; Lacour, D; Laforge, B; Schwemling, P; Abouelouafa, M; Ben-Mansour, A; Cherkaoui, R; El-Mouahhidi, Y; Ghazlane, H; Idrissi, A; Bazizi, K; England, D; Glebov, V; Haelen, T; Lobkowicz, F; Slattery, P F; Belorgey, J; Besson, N; Boonekamp, M; Durand, D; Ernwein, J; Mansouli, B; Molinie, F; Meyer, J P; Perrin, P; Schwindling, J; Taguet, J P; Zaccone, Henri; Lund-Jensen, B; Rydstrm, S; Tayalati, Y; Botchev, B; Finocchiaro, G; Hoffman, J; McCarthy, R L; Rijssenbeek, M; Steffens, J; Zdrazil, M; Braun, H M

2006-01-01T23:59:59.000Z

380

"Light" or the Electromagnetic spectrum www.nasa.gov  

E-Print Network [OSTI]

(absorbed then emitted light) · About the solar atmosphere · About comet tails · About our galaxy · About#12;"Light" or the Electromagnetic spectrum www.nasa.gov #12;Diffraction and Light · When passed through a prism or grating, light is separated into its component wavelengths · This looks like a rainbow

Mojzsis, Stephen J.

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Electromagnetic soliton-particle with spin and magnetic moment  

E-Print Network [OSTI]

Electromagnetic soliton-particle with both quasi-static and quick-oscillating wave parts is considered. Its mass, spin, charge, and magnetic moment appear naturally when the interaction with distant solitons is considered. The substantiation of Dirac equation for the wave part of the interacting soliton-particle is given.

Alexander A. Chernitskii

2012-12-17T23:59:59.000Z

382

Electromagnetic fields and transport coefficients in a hot pion gas  

E-Print Network [OSTI]

We present recent results on finite temperature electromagnetic form factors and the electrical conductivity in a pion gas. The standard Chiral Perturbation Theory power counting needs to be modified for transport coefficients. We pay special attention to unitarity and to possible applications for dilepton and photon production.

A. Gomez Nicola; D. Fernandez-Fraile

2006-08-24T23:59:59.000Z

383

Electromagnetic source localization with finite set of frequency measurements  

E-Print Network [OSTI]

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.

Abdul Wahab; Amer Rasheed; Rab Nawaz; Saman Anjum

2014-09-16T23:59:59.000Z

384

Propagation Analysis of Electromagnetic Waves: Application to Auroral Kilometric Radiation  

E-Print Network [OSTI]

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

Santolik, Ondrej

385

Electromagnetic Waves Propagation in 3D Plasma Configurations  

E-Print Network [OSTI]

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

386

Optical geometry analysis of the electromagnetic self-force  

E-Print Network [OSTI]

We present an analysis of the behaviour of the electromagnetic self-force for charged particles in a conformally static spacetime, interpreting the results with the help of optical geometry. Some conditions for the vanishing of the local terms in the self-force are derived and discussed.

Sebastiano Sonego; Marek A. Abramowicz

2006-02-17T23:59:59.000Z

387

Electromagnetic power loss in open coaxial diodes and the Langmuir-Blodgett law  

SciTech Connect (OSTI)

The space charge limited current in coaxial diodes with electromagnetic power loss is studied. The Langmuir-Blodgett law is expressed in terms of the electromagnetic power loss and the applied voltage. Particle-in-cell simulations of photodiode-like situations and high power diodes confirm the relation between the applied voltage, diode voltage, and electromagnetic power loss.

Kumar, Raghwendra; Biswas, Debabrata [Theoretical Physics Division, Bhabha Atomic Research Centre, Mumbai 400 085 (India)

2010-10-15T23:59:59.000Z

388

Combined Use of Magnetic and Electrically Conductive Fillers in a Polymer Matrix for Electromagnetic Interference Shielding  

E-Print Network [OSTI]

for Electromagnetic Interference Shielding JUNHUA WU1,2 and D.D.L. CHUNG1,3 1.--Composite Materials Research for electromagnetic interference shielding than the use of a highly magnetic filler alone or the use of a highly, magnetic, electrical resistivity, nickel, mumetal, graphite INTRODUCTION Electromagnetic interference (EMI

Chung, Deborah D.L.

389

Electromagnetic interference shielding reaching 70 dB in steel fiber cement  

E-Print Network [OSTI]

Electromagnetic interference shielding reaching 70 dB in steel fiber cement Sihai Wen, D.D.L. Chung; Silica fume; Shielding 1. Introduction Electromagnetic interference (EMI) shielding [1­4] is in critical, NY 14260-4400, USA Received 9 January 2002; accepted 14 August 2003 Abstract An electromagnetic

Chung, Deborah D.L.

390

The influence of single-walled carbon nanotube structure on the electromagnetic interference shielding  

E-Print Network [OSTI]

The influence of single-walled carbon nanotube structure on the electromagnetic interference.01­15%) have been evaluated for electromagnetic interference (EMI) shielding effectiveness (SE) in the X and aerospace sectors with uses such as electrostatic dissipation, electromagnetic interference (EMI) shielding

Gao, Hongjun

391

A Zero-Sum Electromagnetic Evader-Interrogator Differential Game with Uncertainty  

E-Print Network [OSTI]

A Zero-Sum Electromagnetic Evader-Interrogator Differential Game with Uncertainty H.T. Banks-8212 In Memoriam of Prof. L. D. Berkovitz February 21, 2011 Abstract We consider dynamic electromagnetic evasion23, 49N70, 49N90, 65M32, 68T37, 60J70. Key Words: Electromagnetic evasion-pursuit, uncertainty

392

Electromagnetic Interrogation and the Doppler Shift Using the Method of Mappings  

E-Print Network [OSTI]

Electromagnetic Interrogation and the Doppler Shift Using the Method of Mappings H.T. Banks, Shuhua University Raleigh, NC 27695-8212 December 11, 2009 Abstract We consider the electromagnetic detection of a Doppler shift for an electromagnetic wave reflecting from a moving interface. This entails solving Maxwell

393

Introduction Framework Multiscale Expansion Axisymmetric Problems FEM Simulations Postprocessing A Transmission Problem in Electromagnetism with a  

E-Print Network [OSTI]

A Transmission Problem in Electromagnetism with a Singular Interface GABRIEL CALOZ 2 MONIQUE DAUGE 2 ERWAN FAOU 2´eron A Transmission Problem in Electromagnetism with a Singular Interface 1 / 33 inria-00528523,version1-22Oct2010 of electromagnetic fields with depth inside the conductor. The Skin Depth : () = 2/µ0 V. P´eron A Transmission

Paris-Sud XI, Université de

394

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFLE, VICTOR PERON, AND CLAIR POIGNARD  

E-Print Network [OSTI]

THIN LAYER MODELS FOR ELECTROMAGNETISM MARC DURUFL´E, VICTOR P´ERON, AND CLAIR POIGNARD ABSTRACT of electromagnetic waves in domains with thin layer. These models appear as first order approximations of the electromagnetic field. They are obtained thanks to a multiscale expansion of the exact solution with respect

Paris-Sud XI, Université de

395

DERIVATION OF PARTICLE, STRING AND MEMBRANE MOTIONS FROM THE BORN-INFELD ELECTROMAGNETISM  

E-Print Network [OSTI]

DERIVATION OF PARTICLE, STRING AND MEMBRANE MOTIONS FROM THE BORN-INFELD ELECTROMAGNETISM YANN a rigorous asymptotic analysis of the Born-Infeld nonlinear electromagnetic theory. We first add to the Born introduced in [1] as a nonlinear correc- tion to the standard linear Maxwell equations for electromagnetism

Brenier, Yann

396

ON MIMO CHANNEL CAPACITY, SPATIAL SAMPLING AND THE LAWS OF ELECTROMAGNETISM  

E-Print Network [OSTI]

ON MIMO CHANNEL CAPACITY, SPATIAL SAMPLING AND THE LAWS OF ELECTROMAGNETISM Sergey Loyka School by the laws of electromagnetism on achievable MIMO channel capacity in its general form. Our approach is a two expansion of a generic electromagnetic wave combined with Nyquist sampling theorem in the spatial domain, we

Loyka, Sergey

397

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani  

E-Print Network [OSTI]

Electromagnetic Shunt Damping S. Behrens A. J. Fleming S. O. Reza Moheimani School of Electricalqhzfdvwoh1hgx1dx Abstract A method for electromagnetic shunt damping (EMSD) will be presented in this paper. A passive control strategy is validated through experi- mentation on a simple electromagnetic mass

Fleming, Andrew J.

398

ORIGINAL PAPER A new discrete electromagnetism-based meta-heuristic  

E-Print Network [OSTI]

ORIGINAL PAPER A new discrete electromagnetism-based meta-heuristic for solving Electromagnetism-like Mechanism (SEM) is one of the swarm-based optimization methods which is examined Electromagnetism-like Mechanism is proposed which utilizes Genetic Algorithm (GA) operators to work in discrete

Li, Xiaodong

399

Electromagnetically induced torque on a large ring in the microwave range  

E-Print Network [OSTI]

Electromagnetically induced torque on a large ring in the microwave range Olivier EMILE1) Abstract We report on the exchange of Orbital Angular Momentum between an electromagnetic wave and a 30 cm in the detection of angular momentum in electromagnetics, in acoustics and also in the magnetization

Boyer, Edmond

400

ElEctromagnEtic analysis and testing Flap, inside Front cover  

E-Print Network [OSTI]

#12;ElEctromagnEtic analysis and testing Flap, inside Front cover Sandia National Laboratories, homeland security, nonproliferation, and industrial competitiveness. ElEctromagnEtic analysis and testing #12;ElEctromagnEtic analysis and testingElEctromagnEtic analysis and testing Technology that harnesses

Fuerschbach, Phillip

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Particle dynamics and deviation effects in the field of a strong electromagnetic wave  

E-Print Network [OSTI]

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.

Donato Bini; Andrea Geralico; Maria Haney; Antonello Ortolan

2014-08-23T23:59:59.000Z

402

Slanted Annular Aperture Arrays as enhanced-transmission metamaterials: excitation of the plasmonic transverse electromagnetic guided mode  

E-Print Network [OSTI]

transverse electromagnetic guided mode Abdoulaye Ndao1, Abderrahmane Belkhir2, Roland Salut1 and Fadi I

Boyer, Edmond

403

Photoelectron emission from LiF surfaces by ultrashort electromagnetic pulses  

SciTech Connect (OSTI)

Energy- and angle-resolved electron emission spectra produced by incidence of ultrashort electromagnetic pulses on a LiF(001) surface are studied by employing a distorted-wave method named the crystal surface-Volkov (CSV) approximation. The theory makes use of the Volkov phase to describe the action of the external electric field on the emitted electron, while the electron-surface interaction is represented within the tight-binding model. The CSV approach is applied to investigate the effects introduced by the crystal lattice when the electric field is oriented parallel to the surface plane. These effects are essentially governed by the vector potential of the external field, while the influence of the crystal orientation was found to be negligible.

Acuna, M. A. [Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad de Buenos Aires, Buenos Aires (Argentina); Gravielle, M. S. [Instituto de Astronomia y Fisica del Espacio, Consejo Nacional de Investigaciones Cientificas y Tecnicas, Universidad de Buenos Aires, Buenos Aires (Argentina); Departamento de Fisica, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires (Argentina)

2011-03-15T23:59:59.000Z

404

Coherent interaction of a monochromatic gravitational wave with both elastic bodies and electromagnetic circuits  

E-Print Network [OSTI]

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.

Enrico Montanari; Pierluigi Fortini

1998-08-26T23:59:59.000Z

405

On the Casimir energy of the electromagnetic field in the dispersive and absorptive medium  

E-Print Network [OSTI]

The microscopic theory of the Casimir effect in the dielectric is studied in the framework when absorption is realized via a reservoir modeled by a set of oscillators with continuously distributed frquencies with the aim to see if the effects depend on the form of interaction with the reservoir. A simple case of the one-dimensional dielectric between two metallic plates is considered. Two possible models are investigated, the direct interaction of the electromagnetic field with the reservoir and indirect interaction via an intermediate oscillator imitating the atom. It is found that with the same dielectric constant the Casimir effect is different in these two cases, which implies that in the second model it cannot be entirely expressed via the dielectric constant as in the well-known Lifshitz formula.

M. A. Braun

2014-02-16T23:59:59.000Z

406

Nonlinear interaction of intense electromagnetic waves with a magnetoactive electron-positron-ion plasma  

SciTech Connect (OSTI)

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.

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

407

Electromagnetic two-dimensional analysis of trapped-ion eigenmodes  

SciTech Connect (OSTI)

A two-dimensional electromagnetic analysis of the trapped-ion instability for the tokamak case with ..beta.. not equal to 0 has been made, based on previous work in the electrostatic limit. The quasineutrality condition and the component of Ampere's law along the equilibrium magnetic field are solved for the perturbed electrostatic potential and the component of the perturbed vector potential along the equilibrium magnetic field. The general integro-differential equations are converted into a matrix eigenvalue-eigenfunction problem by expanding in cubic B-spline finite elements in the minor radius and in Fourier harmonics in the poloidal angle. A model MHD equilibrium with circular, concentric magnetic surfaces and large aspect ratio is used which is consistent with our assemption that B << 1. The effect on the trapped-ion mode of including these electromagnetic extensions to the calculation is considered, and the temperature (and ..beta..) scaling of the mode frequency is shown and discussed.

Kim, D.; Rewoldt, G.

1984-11-01T23:59:59.000Z

408

Laser photon merging in an electromagnetic field inhomogeneity  

E-Print Network [OSTI]

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.

Holger Gies; Felix Karbstein; Rashid Shaisultanov

2014-08-13T23:59:59.000Z

409

Electromagnetic solitary pulses in a magnetized electron-positron plasma  

SciTech Connect (OSTI)

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.

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

410

Energy harvesting devices for harvesting energy from terahertz electromagnetic radiation  

DOE Patents [OSTI]

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.

Novack, Steven D.; Kotter, Dale K.; Pinhero, Patrick J.

2012-10-09T23:59:59.000Z

411

A new electromagnetic code for ICRF antenna in EAST  

E-Print Network [OSTI]

The demand for an effective tool to help in the design of ion cyclotron radio frequency (ICRF) antenna system for fusion experiment has driven the development of predictive codes. A new electromagnetic code based on the method of moments (MOM) is described in the paper. The code computes the electromagnetic field by the solution of the electric field integral equation. The structure of ICRF antennas are discretized with triangular mesh. By using the new code, the scattering parameter and the surface current are given and compared with the result by commercial code CST. Moreover, the power spectra are studied with different toroidal phases for heating and current drive. Good agreement of simulation results between the new code and CST are obtained. The code has been validated against CST for EAST ICRF antenna.

Yang, Hua; Dong, Sa; Zhang, Xin-Jun; Zhao, Yan-Ping; Shang, Lei

2015-01-01T23:59:59.000Z

412

Structures, systems and methods for harvesting energy from electromagnetic radiation  

DOE Patents [OSTI]

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.

Novack, Steven D. (Idaho Falls, ID); Kotter, Dale K. (Shelley, ID); Pinhero, Patrick J. (Columbia, MO)

2011-12-06T23:59:59.000Z

413

Electromagnetic and nuclear radiation detector using micromechanical sensors  

DOE Patents [OSTI]

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.

Thundat, Thomas G. (Knoxville, TN); Warmack, Robert J. (Knoxville, TN); Wachter, Eric A. (Oak Ridge, TN)

2000-01-01T23:59:59.000Z

414

Nuclear electromagnetic charge and current operators in Chiral EFT  

SciTech Connect (OSTI)

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.

Girlanda, Luca [Universit 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

415

Gradient instabilities of electromagnetic waves in Hall thruster plasma  

SciTech Connect (OSTI)

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.

Tomilin, Dmitry [Department of Electrophysics, Keldysh Research Centre, Moscow 125438 (Russian Federation)

2013-04-15T23:59:59.000Z

416

Low-frequency electromagnetic field in a Wigner crystal  

SciTech Connect (OSTI)

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.

Stupka, Anton [Oles Honchar Dnipropetrovs'k National University, Gagarin Ave., 72, 49010 Dnipropetrovs'k (Ukraine)

2013-03-15T23:59:59.000Z

417

Technical Design Report for PANDA Electromagnetic Calorimeter (EMC)  

E-Print Network [OSTI]

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.

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

418

Conservation of the spin and orbital angular momenta in electromagnetism  

E-Print Network [OSTI]

We review and re-examine the description and separation of the spin and orbital angular momenta (AM) of an electromagnetic field in free space. While the spin and orbital AM of light are not separately-meaningful physical quantities in orthodox quantum mechanics or classical field theory, these quantities are routinely measured and used for applications in optics. A meaningful quantum description of the spin and orbital AM of light was recently provided by several authors, which describes separately conserved and measurable integral values of these quantities. However, the electromagnetic field theory still lacks corresponding locally-conserved spin and orbital AM currents. In this paper, we construct these missing spin and orbital AM densities and fluxes that satisfy the proper continuity equations. We show that these are physically measurable and conserved quantities. These are, however, not Lorentz-covariant, so only make sense in the single laboratory reference frame of the measurement probe. The fluxes we derive improve the canonical (non-conserved) spin and orbital AM fluxes, and include a `spin-orbit' term that describes the spin-orbit interaction effects observed in nonparaxial optical fields. We also consider both standard and dual-symmetric versions of the electromagnetic field theory. Applying the general theory to nonparaxial optical vortex beams validates our results and allows us to discriminate between earlier approaches to the problem. Our treatment yields the complete and consistent description of the spin and orbital AM of free Maxwell fields in both quantum-mechanical and field-theory approaches.

Konstantin Y. Bliokh; Justin Dressel; Franco Nori

2014-08-03T23:59:59.000Z

419

Detecting excess ionizing radiation by electromagnetic breakdown of air  

SciTech Connect (OSTI)

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.

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

420

Spontaneous emission of a two-level static atom coupling with the electromagnetic vacuum fluctuations outside a high-dimensional Einstein Gauss-Bonnet black hole  

E-Print Network [OSTI]

In present paper, by using the generalized DDC formalism, we investigate the spontaneous excitation of an static atom interacting with electromagnetic vacuum fluctuations outside a EGB black hole in $d$-dimensions. We find that spontaneous excitation does not occur in Boulware vacuum. The Gauss-Bonnet term has no effect on the stability of the atom. Finally, we discuss the contribution of the coupling constant and dimensional factor to the results in three different kinds of spacetime.

Ming Zhang; Zhan-Ying Yang; Rui-Hong Yue

2014-07-04T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

TESTING GROUND BASED GEOPHYSICAL TECHNIQUES TO REFINE ELECTROMAGNETIC SURVEYS NORTH OF THE 300 AREA HANFORD WASHINGTON  

SciTech Connect (OSTI)

Airborne electromagnetic (AEM) surveys were flown during fiscal year (FY) 2008 within the 600 Area in an attempt to characterize the underlying subsurface and to aid in the closure and remediation design study goals for the 200-PO-1 Groundwater Operable Unit (OU). The rationale for using the AEM surveys was that airborne surveys can cover large areas rapidly at relatively low costs with minimal cultural impact, and observed geo-electrical anomalies could be correlated with important subsurface geologic and hydrogeologic features. Initial interpretation of the AEM surveys indicated a tenuous correlation with the underlying geology, from which several anomalous zones likely associated with channels/erosional features incised into the Ringold units were identified near the River Corridor. Preliminary modeling resulted in a slightly improved correlation but revealed that more information was required to constrain the modeling (SGW-39674, Airborne Electromagnetic Survey Report, 200-PO-1 Groundwater Operable Unit, 600 Area, Hanford Site). Both time-and frequency domain AEM surveys were collected with the densest coverage occurring adjacent to the Columbia River Corridor. Time domain surveys targeted deeper subsurface features (e.g., top-of-basalt) and were acquired using the HeliGEOTEM{reg_sign} system along north-south flight lines with a nominal 400 m (1,312 ft) spacing. The frequency domain RESOLVE system acquired electromagnetic (EM) data along tighter spaced (100 m [328 ft] and 200 m [656 ft]) north-south profiles in the eastern fifth of the 200-PO-1 Groundwater OU (immediately adjacent to the River Corridor). The overall goal of this study is to provide further quantification of the AEM survey results, using ground based geophysical methods, and to link results to the underlying geology and/or hydrogeology. Specific goals of this project are as follows: (1) Test ground based geophysical techniques for the efficacy in delineating underlying geology; (2) Use ground measurements to refine interpretations of AEM data; and (3) Improve the calibration and correlation of AEM information. The potential benefits of this project are as follows: (1) Develop a tool to map subsurface units at the Hanford Site in a rapid and cost effective manner; (2) Map groundwater pathways within the River Corridor; and (3) Aid development of the conceptual site model. If anomalies observed in the AEM data can be correlated with subsurface geology, then the rapid scanning and non-intrusive capabilities provided by the airborne surveys can be used at the Hanford Site to screen for areas that warrant further investigation.

PETERSEN SW

2010-12-02T23:59:59.000Z

422

Pion light-front wave function, parton distribution and the electromagnetic form factor  

E-Print Network [OSTI]

We derive a light-front wave function of the pion, which reproduces its valence parton distribution and a electromagnetic form factor consistent with data.

Thomas Gutsche; Valery E. Lyubovitskij; Ivan Schmidt; Alfredo Vega

2014-10-23T23:59:59.000Z

423

E-Print Network 3.0 - ambient electromagnetic fields Sample Search...  

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

Analysis Techniques Summary: & Technology Introduction Products fail electromagnetic interference (EMI) tests. This can be a disappointing... , and antenna. No single method...

424

Full-wave algorithms for model order reduction and electromagnet analysis of impedance and scattering  

E-Print Network [OSTI]

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 ...

Klemas, Thomas J. (Thomas Jonas)

2005-01-01T23:59:59.000Z

425

Electromagnetic Structure Functions of Nucleons in the Region of Very Small X  

E-Print Network [OSTI]

A two component model describing the electromagnetic nucleon structure functions in the low-x region, based on generalized vector dominance and color dipole approaches is briefly described.

E. V. Bugaev; B. V. Mangazeev

2011-02-12T23:59:59.000Z

426

E-Print Network 3.0 - accelerating electromagnetic magic Sample...  

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

accelerating electromagnetic magic Page: << < 1 2 3 4 5 > >> 1 Very High Energy Gamma Ray Observations with the MAGIC Summary: Very High Energy Gamma Ray Observations with the...

427

Surfatron acceleration of protons by an electromagnetic wave at the heliosphere periphery  

SciTech Connect (OSTI)

The trapping and subsequent efficient surfatron acceleration of weakly relativistic protons by an electromagnetic wave propagating across an external magnetic field in plasma at the heliosphere periphery is considered. The problem is reduced to analysis of a second-order time-dependent nonlinear equation for the wave phase on the particle trajectory. The conditions of proton trapping by the wave, the dynamics of the components of the particle momentum and velocity, the structure of the phase plane, the particle trajectories, and the dependence of the acceleration rate on initial parameters of the problem are analyzed. The asymptotic behavior of the characteristics of accelerated particles for the heliosphere parameters is investigated. The optimum conditions for surfatron acceleration of protons by an electromagnetic wave are discussed. It is demonstrated that the experimentally observed deviation of the spectra of cosmic-ray protons from standard power-law dependences can be caused by the surfatron mechanism. It is shown that protons with initial energies of several GeV can be additionally accelerated in the heliosphere (the region located between the shock front of the solar wind and the heliopause at distances of about 100 astronomical units (a.u.) from the Sun) up to energies on the order of several thousands of GeV. In order to explain the proton spectra in the energy range of ?20500 GeV, a two-component phenomenological model is proposed. The first component corresponds to the constant (in this energy range) galactic contribution, while the second (variable) component corresponds to the heliospheric contribution, which appears due to the additional acceleration of soft cosmic-ray protons at the heliosphere periphery. Variations in the proton spectra measured on different time scales between 1992 and 2008 in the energy range from several tens to several hundred GeV, as well as the dependence of these spectra on the heliospheric weather, can be explained by surfatron acceleration of protons in the heliosphere.

Loznikov, V. M., E-mail: loznikov@yandex.ru; Erokhin, N. S.; Zolnikova, N. N.; Mikhailovskaya, L. A. [Russian Academy of Sciences, Space Research Institute (Russian Federation)] [Russian Academy of Sciences, Space Research Institute (Russian Federation)

2013-10-15T23:59:59.000Z

428

Electromagnetic power of merging and collapsing compact objects  

E-Print Network [OSTI]

[Abridged] Electromagnetic emission can be produced as a precursor to the merger, as a prompt emission during the collapse of a NS and at the spin-down stage of the resulting BH. We demonstrate that the time evolution of the axisymmetric force-free magnetic fields can be expressed in terms of the hyperbolic Grad-Shafranov equation. We find exact non-linear time-dependent split-monopole structure of magnetosphere driven by spinning and collapsing NS in Schwarzschild geometry. Based on this solution, we argue that the collapse of a NS into the BH happens smoothly, without natural formation of current sheets or other dissipative structures on the open field lines and, thus, does not allow the magnetic field to become disconnected from the star and escape to infinity. Thus, as long as an isolated Kerr BH can produce plasma and currents, it does not lose its open magnetic field lines, its magnetospheric structure evolved towards a split monopole and the BH spins down electromagnetically. The "no hair theorem", which assumes that the outside medium is a vacuum, is not applicable in this case: highly conducting plasma introduces a topological constraint forbidding the disconnection of the magnetic field lines from the BH. Eventually, a single random large scale spontaneous reconnection event will lead to magnetic field release, shutting down the electromagnetic BH engine forever. We also discuss the nature of short Gamma Ray Bursts and suggest that the similarity of the early afterglows properties of long and short GRBs can be related to the fact that in both cases a spinning BH can retains magnetic field for sufficiently long time to extract a large fraction of its rotation energy and produce high energy emission via the internal dissipation in the wind.

Maxim Lyutikov

2011-04-06T23:59:59.000Z

429

Spectrum of the volume integral operator of electromagnetic scattering  

E-Print Network [OSTI]

Spectrum of the volume integral operator of the three-dimensional electromagnetic scattering is analyzed. The operator has both continuous essential spectrum, which dominates at lower frequencies, and discrete eigenvalues, which spread out at higher ones. The explicit expression of the operator's symbol provides exact outline of the essential spectrum for any inhomogeneous anisotropic scatterer with Holder continuous constitutive parameters. Geometrical bounds on the location of discrete eigenvalues are derived for various physical scenarios. Numerical experiments demonstrate good agreement between the predicted spectrum of the operator and the eigenvalues of its discretized version.

Neil V. Budko; Alexander B. Samokhin

2005-05-04T23:59:59.000Z

430

Pion electromagnetic form factor in the Covariant Spectator Theory  

SciTech Connect (OSTI)

The pion electromagnetic form factor at spacelike momentum transfer is calculated in relativistic impulse approximation using the Covariant Spectator Theory. The same dressed quark mass function and the equation for the pion bound-state vertex function as discussed in the companion paper are used for the calculation, together with a dressed quark current that satisfies the Ward-Takahashi identity. The results obtained for the pion form factor are in agreement with experimental data, they exhibit the typical monopole behavior at high momentum transfer and they satisfy some remarkable scaling relations.

Biernat, Elmar P. [CFTP, Institute Superior Tecnico, Lisboa (Portugal); Gross, Franz L. [JLAB, Newport News, VA (United States); Pena, Teresa [CFTP, Institute Superior Tecnico, Lisboa (Portugal); Stadler, Alfred [University of Evora, Lisboa (Portugal)

2014-01-01T23:59:59.000Z

431

Magnetically coupled electromagnetically induced transparency analogy of dielectric metamaterial  

SciTech Connect (OSTI)

In this manuscript, we experimentally demonstrate magnetically coupled electromagnetically induced transparency (EIT) analogy effect inside dielectric metamaterial. In contrast to previous studies employed different metallic topological microstructures to introduce dissipation loss change, barium strontium titanate, and calcium titanate (CaTiO{sub 3}) are chosen as the bright and dark EIT resonators, respectively, due to their different intrinsic dielectric loss. Under incident magnetic field excitation, dielectric metamaterial exhibits an EIT-type transparency window around 8.9?GHz, which is accompanied by abrupt change of transmission phase. Numerical calculations show good agreement with experiment spectra and reveal remarkably increased group index, indicating potential application in slow light.

Zhang, Fuli, E-mail: fuli.zhang@nwpu.edu.cn; He, Xuan [Key Laboratory of Space Applied Physics and Chemistry, Ministry of Education and Department of Applied Physics, School of Science, Northwestern Polytechnical University, Xi'an 710072 (China); Zhao, Qian [State Key Laboratory of Tribology, Department of Mechanical Engineering, Tsinghua University, Beijing 100084 (China); Lan, Chuwen; Zhou, Ji [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Zhang, Weihong, E-mail: zhangwh@nwpu.edu.cn; Qiu, Kepeng [School of Mechanical Engineering, P.O. Box 552, Northwestern Polytechnical University, Xi'an 710072 (China)

2014-03-31T23:59:59.000Z

432

Spectroscopy of strontium Rydberg states using electromagnetically induced transparency  

E-Print Network [OSTI]

We report on the all-optical detection of Rydberg states in a effusive atomic beam of strontium atoms using electromagnetically induced transparency (EIT). Using narrow-linewidth CW lasers we obtain an EIT linewidth of 5 MHz. To illustrate the high spectroscopic resolution offered by this method, we have measured isotope shifts of the 5s18d ^1D_2 and 5s19s ^1S_0 Rydberg states. This technique could be applied to high-resolution, non-destructive measurements of ultra-cold Rydberg gases and plasmas.

S. Mauger; J. Millen; M. P. A. Jones

2007-10-05T23:59:59.000Z

433

Dr. S. Cruz-Pol, INEL 4151-Electromagnetics I  

E-Print Network [OSTI]

! dt d NVemf -= -= sL dSB t dlE Electromagnetics was born! ? This is the principle of motors = magnetic field density, [Teslas] mH mF HB ED o o /104 36 10 /1085.8 7 9 12 - - - ?= =?= = = µ µ #12;Dr://micro.magnet.fsu.edu/electromag/java/generator/dc.html BlIF BuQF ?= ?= Encarta® Who was NikolaTesla? ?Find out what inventions he made ?His relation

Cruz-Pol, Sandra L.

434

Electromagnetically induced transparency in mechanical effects of light  

SciTech Connect (OSTI)

We consider the dynamical behavior of a nanomechanical mirror in a high-quality cavity under the action of a coupling laser and a probe laser. We demonstrate the existence of the analog of electromagnetically induced transparency (EIT) in the output field at the probe frequency. Our calculations show explicitly the origin of EIT-like dips as well as the characteristic changes in dispersion from anomalous to normal in the range where EIT dips occur. Remarkably the pump-probe response for the optomechanical system shares all the features of the {Lambda} system as discovered by Harris and collaborators.

Agarwal, G. S.; Huang, Sumei [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2010-04-15T23:59:59.000Z

435

Electromagnetically induced transparency with quantized fields in optocavity mechanics  

SciTech Connect (OSTI)

We report electromagnetically induced transparency (EIT) using quantized fields in optomechanical systems. The weak probe field is a narrowband squeezed field. We present a homodyne detection of EIT in the output quantum field. We find that the EIT dip exists even though the photon number in the squeezed vacuum is at the single-photon level. The EIT with quantized fields can be seen even at temperatures on the order of 100 mK, thus paving the way for using optomechanical systems as memory elements.

Huang Sumei; Agarwal, G. S. [Department of Physics, Oklahoma State University, Stillwater, Oklahoma 74078 (United States)

2011-04-15T23:59:59.000Z

436

Modified definition of group velocity and electromagnetic energy conservation equation  

E-Print Network [OSTI]

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.

Changbiao Wang

2015-01-19T23:59:59.000Z

437

Electromagnetic gearing applications in hybrid-electric vehicles  

E-Print Network [OSTI]

switched reluctance electromagnetic gear in mode 2b. . . . . 67 3. 12 Mode 2c. m, = 0, m, & 0, T, & 0. 68 LIST OF FIGURES (Continued) Figure Page 3. 13 Mode 2d. ca, = 0, c0, & 0, T, & 0. 69 3. 14 a). Phase A-A' is permanently energized. Rotor poles 1...-up of the transmotor hybrid. 127 5. 10 Engine runs at no load and the transmotor is de-energized. . . . 128 5. 11 Forward motion of the transmotor hybrid. 129 5. 12 Forward braking of the vehicle. 133 5. 13 Reverse direction motion of the vehicle. 135 5. 14...

Sodhi, Sameer

1994-01-01T23:59:59.000Z

438

Charge quantisation without magnetic monopoles: a topological approach to electromagnetism  

E-Print Network [OSTI]

The present work provides a theoretical explanation for the quantisation of electric charges, an open problem since Millikan's oil drop experiment in 1909. This explanation is based solely on Maxwell's theory, it recasts Electromagnetic theory under the language of complex line bundles; therefore, neither magnetic monopoles nor quantum mechanics are invoked. Essentially, the existence of magnetic monopoles was the only theoretical explanation for charge quantisation (e.g. Dirac's monopole), and there is no experimental data supporting their existence ---on the contrary, they have nerver been observed.

Romero Solha

2014-06-24T23:59:59.000Z

439

Nucleon Electromagnetic Form Factors: Free Space and Medium Modifications  

SciTech Connect (OSTI)

We review recent developments in the study of electromagnetic form factors of the nucleon, both in free space and in the nuclear medium. For the free nucleon case, we discuss the ratio of electric to magnetic proton form factors, and the influence of two-photon exchange on the form factor extraction. For the bound nucleon, we examine the implications of the small but non-zero modification of proton form factors in the nuclear medium suggested by recent data on polarized proton knockout reactions off He-4, and discuss constraints which it could place on models of the nuclear EMC effect.

Wally Melnitchouk

2003-10-01T23:59:59.000Z

440

Electromagnetic scattering from grassland Part II: Measurement and modeling results  

E-Print Network [OSTI]

-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(M68SM74F80)receivedthe B.S.degreeinphysicsfromtheAmericanUniversity of Beirut, Lebanon, in 1964, and the M.S.E.E. and Ph.D.degreesinelectricalengineeringfromtheUni- versity...

Stiles, James Marion; Ulaby, F. T.; Sarabandi, K.

2000-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Nucleon electromagnetic form factors from twisted mass lattice QCD  

E-Print Network [OSTI]

Results on the electromagnetic form factors of the nucleon using twisted mass fermion configurations are presented. These include a gauge field ensemble simulated with two degenerate light quarks yielding a pion mass of around 130 MeV, as well as two ensembles that include strange and charm quarks in the sea yielding pion masses of 210 MeV and 373 MeV. Details of the methods used and systematic errors are discussed, such as noise reduction techniques and the effect of excited states contamination.

Abdou Abdel-Rehim; Constantia Alexandrou; Martha Constantinou; Kyriakos Hadjiyiannakou; Karl Jansen; Giannis Koutsou

2015-01-07T23:59:59.000Z

442

Nucleon electromagnetic form factors from twisted mass lattice QCD  

E-Print Network [OSTI]

Results on the electromagnetic form factors of the nucleon using twisted mass fermion configurations are presented. These include a gauge field ensemble simulated with two degenerate light quarks yielding a pion mass of around 130 MeV, as well as two ensembles that include strange and charm quarks in the sea yielding pion masses of 210 MeV and 373 MeV. Details of the methods used and systematic errors are discussed, such as noise reduction techniques and the effect of excited states contamination.

Abdel-Rehim, Abdou; Constantinou, Martha; Hadjiyiannakou, Kyriakos; Jansen, Karl; Koutsou, Giannis

2015-01-01T23:59:59.000Z

443

Evaluation of electromagnetic stimulation of Texas heavy oil reservoirs  

E-Print Network [OSTI]

- Iil Z LLI ) I- O LI III ) D- Z 00 + 0 CI z 0 I- U CI 0 K 0. CI D VERTICAL HEAT LOSS tt44 OVERBURDEN FLUID FLOW CONVECTION CONDUCTION P= Pe T=Te VERTICAL HEAT LOSS ~ ELECTROMAGNETIC WAVE Fig. 2 ? Schematic View of EMH Process 12... The ProPerties that affected the heated oil production rate the most were initial oil viscosity, formation ~ility, drainage radius, p~e drop, and ~ture. The heated oil prcduction rate estimation equation was applied to 80 Texas heavy oil ~irs to de...

Doublet, Louis Edward

1988-01-01T23:59:59.000Z

444

Image Appraisal for 2D and 3D Electromagnetic Inversion  

SciTech Connect (OSTI)

Linearized methods are presented for appraising image resolution and parameter accuracy in images generated with two and three dimensional non-linear electromagnetic inversion schemes. When direct matrix inversion is employed, the model resolution and posterior model covariance matrices can be directly calculated. A method to examine how the horizontal and vertical resolution varies spatially within the electromagnetic property image is developed by examining the columns of the model resolution matrix. Plotting the square root of the diagonal of the model covariance matrix yields an estimate of how errors in the inversion process such as data noise and incorrect a priori assumptions about the imaged model map into parameter error. This type of image is shown to be useful in analyzing spatial variations in the image sensitivity to the data. A method is analyzed for statistically estimating the model covariance matrix when the conjugate gradient method is employed rather than a direct inversion technique (for example in 3D inversion). A method for calculating individual columns of the model resolution matrix using the conjugate gradient method is also developed. Examples of the image analysis techniques are provided on 2D and 3D synthetic cross well EM data sets, as well as a field data set collected at the Lost Hills Oil Field in Central California.

Alumbaugh, D.L.; Newman, G.A.

1999-01-28T23:59:59.000Z

445

Testing Loop Quantum Gravity and Electromagnetic Dark Energy in Superconductors  

E-Print Network [OSTI]

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.

Clovis Jacinto de Matos

2009-08-06T23:59:59.000Z

446

Addressing the susceptibility of digital systems to electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant`s electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V&V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance criteria to ensure that the circuit or system under test meets the recommended guidelines. V&V should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. [Oak Ridge National Lab., TN (US); Antonescu, C. [Nuclear Regulatory Commission, Rockville, MD (US). Office of Nuclear Regulatory Research

1993-06-01T23:59:59.000Z

447

Addressing the susceptibility of digital systems to electromagnetic interference  

SciTech Connect (OSTI)

This paper discusses the development of the technical basis for acceptance criteria applicable to the immunization of digital systems against electromagnetic interference (EMI). The work is sponsored by the US Nuclear Regulatory Commission and stems from the safety-related issues that need to be addressed as a result of the application of digital instrumentation and control systems in nuclear power plants. Designers of digital circuits are incorporating increasingly higher clock frequencies and lower logic level voltages, thereby leading to potentially greater susceptibility of spurious interference being misinterpreted as legitimate logic. Development of the technical basis for acceptance criteria to apply to these digital systems centers around establishing good engineering practices to ensure that sufficient levels of electromagnetic compatibility (EMC) are maintained between the nuclear power plant's electronic and electromechanical systems. First, good EMC design and installation practices are needed to control the emissions from interference sources and thereby their impact on other nearby circuits and systems. Second, a verification and validation (V V) program is needed to outline the EMI tests to be performed, the associated test methods to be followed, and adequate acceptance criteria to ensure that the circuit or system under test meets the recommended guidelines. V V should be followed by periodic maintenance to assess whether the recommended EMI control practices continue to be adhered to as part of the routine operation of the nuclear power plant. By following these steps, the probability of encountering safety-related instrumentation susceptibility attributable to EMI will be greatly reduced.

Ewing, P.D.; Korsah, K. (Oak Ridge National Lab., TN (United States)); Antonescu, C. (Nuclear Regulatory Commission, Rockville, MD (United States). Office of Nuclear Regulatory Research)

1993-01-01T23:59:59.000Z

448

Three-Dimensional Electromagnetic High Frequency Axisymmetric Cavity Scars.  

SciTech Connect (OSTI)

This report examines the localization of high frequency electromagnetic fi elds in three-dimensional axisymmetric cavities along periodic paths between opposing sides of the cavity. The cases where these orbits lead to unstable localized modes are known as scars. This report treats both the case where the opposing sides, or mirrors, are convex, where there are no interior foci, and the case where they are concave, leading to interior foci. The scalar problem is treated fi rst but the approximations required to treat the vector fi eld components are also examined. Particular att ention is focused on the normalization through the electromagnetic energy theorem. Both projections of the fi eld along the scarred orbit as well as point statistics are examined. Statistical comparisons are m ade with a numerical calculation of the scars run with an axisymmetric simulation. This axisymmetric cas eformstheoppositeextreme(wherethetwomirror radii at each end of the ray orbit are equal) from the two -dimensional solution examined previously (where one mirror radius is vastly di ff erent from the other). The enhancement of the fi eldontheorbitaxiscanbe larger here than in the two-dimensional case. Intentionally Left Blank

Warne, Larry K.; Jorgenson, Roy E.

2014-10-01T23:59:59.000Z

449

Infrared nullification of the effective electromagnetic field at finite temperature  

E-Print Network [OSTI]

The problem of infrared divergence of the effective electromagnetic field at finite temperature (T) is revisited. A model of single spatially localized electron interacting with thermal photons is considered in the limit T to 0 using two different regularization schemes. The first is based on the shift i 0 to i varepsilon of the electron propagator pole in the complex energy plane, and is used to explicitly calculate the effective field in the one-loop approximation. We show that the matrix-valued imaginary part of the electron self-energy can be consistently related to the pole shift, and that the presence of the heat bath leads to appearance of an effective varepsilon sim T, thus providing a natural infrared regulator of the theory. We find that the one-loop effective Coulomb field calculated using this varepsilon vanishes. The other scheme combines an infrared momentum cutoff with smearing of the delta-functions in the interaction vertices. We prove that this regularization admits factorization of the infrared contributions in multi-loop diagrams, and sum the corresponding infinite series. The effective electromagnetic field is found to vanish in this case too. An essentially perturbative nature of this result is emphasized and discussed in connection with the long-range expansion of the effective field.

Kirill A. Kazakov; Vladimir V. Nikitin

2009-10-30T23:59:59.000Z

450

Electromagnetic confinement for vertical casting or containing molten metal  

DOE Patents [OSTI]

An apparatus and method adapted to confine a molten metal to a region by means of an alternating electromagnetic field. As adapted for use in the present invention, the alternating electromagnetic field given by B.sub.y =(2.mu..sub.o .rho.gy).sup.1/2 (where B.sub.y is the vertical component of the magnetic field generated by the magnet at the boundary of the region; y is the distance measured downward form the top of the region, .rho. is the metal density, g is the acceleration of gravity and .mu..sub.o is the permeability of free space) induces eddy currents in the molten metal which interact with the magnetic field to retain the molten metal with a vertical boudnary. As applied to an apparatus for the continuous casting of metal sheets or rods, metal in liquid form can be continuously introduced into the region defined by the magnetic field, solidified and conveyed away from the magnetic field in solid form in a continuous process.

Lari, Robert J. (Aurora, IL); Praeg, Walter F. (Palos Park, IL); Turner, Larry R. (Naperville, IL)

1991-01-01T23:59:59.000Z

451

A conceptual design for the STAR endcap electromagnetic calorimeter  

SciTech Connect (OSTI)

In order to make measurements of the gluon spin or helicity distribution in the proton or the gluon spin average distribution in nuclei, both a barrel and an endcap electromagnetic calorimeter must be added to the STAR baseline detector. Information on the gluon will be obtained in inclusive direct-{gamma} + jet and jet + jet production. In order to be sensitive to the proper gluon kinematic regions, either the direct-{gamma} or the jet must be in the endcap electromagnetic calorimeter (EMC). However, the endcap EMC is not large enough to completely contain the jets, so that the barrel EMC is also needed. This note describes a conceptual design for the STAR endcap EMC. Constraints are imposed by the space available between the end of the time projection chamber (TPC) and the inside of the magnet pole tip iron. Severe constraints also occur near {vert_bar}{eta}{vert_bar} = 1, where the barrel and endcap EMC`s meet. Cables from detectors inside the EMC, including those from the TPC, will exit from STAR near {vert_bar}{eta}{vert_bar} = 1. The constraints in this region have not yet been seriously studied since no decision on the detailed routing of these cables was available at the time this work was being done. This report includes details of the conceptual design, analytical and finite element calculations of stresses in various structural members for the endcap EMC, and a preliminary cost estimate.

Bielick, E.; Fornek, T.; Spinka, H.; Underwood, D.G.

1993-08-09T23:59:59.000Z

452

High frequency electromagnetic burn monitoring for underground coal gasification  

SciTech Connect (OSTI)

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.

Deadrick, F.J.; Hill, R.W.; Laine, E.F.

1981-06-17T23:59:59.000Z

453

Project title: Principal Investigator(s)  

E-Print Network [OSTI]

No. 0123 Project title: Principal Investigator(s): Funding Agency: Submission deadline: Instruments, redeployment costs) OBS engineering and technical support cost: (on shore and at sea) Shipping: Travel and technical support for OBS operations at sea. The cost of providing this support (e.g., instrument charges

Menke, William

454

WSEAS TRANS. ON INFORMATION SCIENCE & APPLICATIONS Issue 5, Volume 2, May 2005 ISSN: 1790-0832 587 Optimization Algorithms Inspired by Electromagnetism and Stigmergy  

E-Print Network [OSTI]

Optimization Algorithms Inspired by Electromagnetism and Stigmergy in Electro-technical Engineering PETER presents a comparative study of two stochastic optimization methods: the electromagnetism-like algorithm with the EMA. Key-Words: - electromagnetism, multilevel, stigmergy, optimization, design 1 Introduction

Silc, Jurij

455

Electromagnetic properties of NiZn ferrite nanoparticles and their polymer composites  

SciTech Connect (OSTI)

The magnetic properties of polycrystalline NiZn ferrite nanoparticles synthesized using a polyol-reduction and coprecipitation reaction methods have been investigated. The effects on magnetization of synthesis approach, chemical composition, processing conditions, and on the size of nanoparticles on magnetization have been investigated. The measured room-temperature magnetization for the as-prepared magnetic nanoparticles (MNP) synthesized via polyol-reduction and coprecipitation is 69?Am{sup 2}?kg{sup ?1} and 14?Am{sup 2}?kg{sup ?1}, respectively. X-ray diffraction measurements confirm spinel structure of the particles with an estimated grain size of ?80?nm obtained from the polyol-reduction and 28?nm obtained from these coprecipitation techniques. Upon calcination under atmospheric conditions at different temperatures between 800?C and 1000?C, the magnetization, M, of the coprecipitated MNP increases to 76?Am{sup 2}?kg{sup ?1} with an estimated grain size of 90?nm. The MNP-polymer nanocomposites made from the synthesized MNP in various loading fraction and high density polyethylene exhibit interesting electromagnetic properties. The measured permeability and permittivity of the magnetic nanoparticle-polymer nanocomposites increases with the loading fractions of the magnetic nanoparticles, suggesting control for impedance matching for antenna applications.

Parsons, P. [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving Ground, Maryland 21005 (United States); Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Duncan, K. [U.S. Army, Communications-Electronics Research, Development and Engineering Center, Space and Terrestrial Communications Directorate, Aberdeen Proving Ground, Maryland 21005 (United States); Giri, A. K. [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving Ground, Maryland 21005 (United States); Bowhead Science and Technology, LLC, Belcamp, Maryland 21017 (United States); Xiao, J. Q. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Karna, S. P., E-mail: shashi.p.karna.civ@mail.mil [U.S. Army Research Laboratory, Weapons and Materials Research Directorate, Aberdeen Proving Ground, Maryland 21005 (United States)

2014-05-07T23:59:59.000Z

456

Standing electromagnetic solitons in hot ultra-relativistic electron-positron plasmas  

SciTech Connect (OSTI)

Using a one-dimensional self-consistent fluid model, we investigate standing relativistic bright solitons in hot electron-positron plasmas. The positron dynamics is taken into account. A set of nonlinear coupled differential equations describing the evolution of electromagnetic waves in fully relativistic two-fluid plasma is derived analytically and solved numerically. As a necessary condition for the existence of standing solitons the system should be relativistic. For the case of ultra-relativistic plasma, we investigate non-drifting bright solitary waves. Detailed discussions of the acceptable solutions are presented. New single hump non-trivial symmetric solutions for the scalar potential were found, and single and multi-nodal symmetric and anti-symmetric solutions for the vector potential are presented. It is shown that for a fixed value of the fluid velocity excited modes with more zeros in the profile of the vector potential show a higher magnitude for the scalar potential. An increase in the plasma fluid velocity also increases the magnitude of the scalar potential. Furthermore, the Hamiltonian and the first integral of the system are given.

Heidari, E., E-mail: ehphys75@iaubushehr.ac.ir [Department of Sciences, Bushehr Branch, Islamic Azad University, Bushehr (Iran, Islamic Republic of); Aslaninejad, M. [Plasma Physics Research Centre, Science and Research Branch, Islamic Azad University, P.O. Box 14665-678, Tehran (Iran, Islamic Republic of)] [Plasma Physics Research Centre, Science and Research Branch, Islamic Azad University, P.O. Box 14665-678, Tehran (Iran, Islamic Republic of); Eshraghi, H. [Physics Department, Iran University of Science and Technology (IUST), P.O. Box 1684613114, Tehran (Iran, Islamic Republic of)] [Physics Department, Iran University of Science and Technology (IUST), P.O. Box 1684613114, Tehran (Iran, Islamic Republic of); Rajaee, L. [Department of Physics, Faculty of Science, University of Qom, Qom (Iran, Islamic Republic of)] [Department of Physics, Faculty of Science, University of Qom, Qom (Iran, Islamic Republic of)

2014-03-15T23:59:59.000Z

457

Merging and splitting of clusters in the electromagnetic calorimeter of the KLOE detector  

E-Print Network [OSTI]

The work was carried out in the framework of the KLOE collaboration studying the decays of the phi meson produced in the DAFNE accelerator in the collisions of electron and positron. The main aim of this thesis was investigation of the influence of the merging and splitting of clusters in decays with the high multiplicity of gamma quanta, which are at most biased by these effects. For this aim we implemented the full geometry and realistic material composition of the barrel electromagnetic calorimeter in FLUKA package. The prepared Monte Carlo based simulation program permits to achieve a fast generation of the detector response separately for each interested reaction. The program was used to study the reconstruction efficiency with the KLOE clustering algorithm as a function of the photocathode quantum efficiency. It was also used to investigate merging and splitting probabilities as a function of the quantum efficiency. The conducted studies indicated that the increase of quantum efficiency does not improve significantly the identification of clusters. The influence of these effects was estimated for eta meson decays into 3 neutral pions and K_short meson into 2 neutral pions.

Jaroslaw Zdebik

2008-11-09T23:59:59.000Z

458

Investigating Iron Ions | EMSL  

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

Investigating Iron Ions Investigating Iron Ions Computer code provides detailed predictions of highly charged ions in water Using resources at EMSL, scientists obtained...

459

THE BIANCHI IDENTITIES, ELECTROMAGNETIC WAVES, AND CHARGE CONSERVATION IN THE P(4) THEORY OF  

E-Print Network [OSTI]

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

Norris, Larry K.

460

A method for calculating wide band electromagnetic interference from power line corona  

SciTech Connect (OSTI)

An algorithm for calculating electromagnetic interference from power line corona for a range of frequencies from 100 kHz to 30 MHz is demonstrated. It can be used for calculations at any distance or direction from the line. The algorithm incorporates an existing generation function which has been optimized by comparison to long term electromagnetic interference measurements.

Olsen, R.G. [Washington State Univ., Pullman, WA (United States). School of Electrical Engineering and Computer Science] [Washington State Univ., Pullman, WA (United States). School of Electrical Engineering and Computer Science; Schennum, S.D. [Gonzaga Univ., Spokane, WA (United States)] [Gonzaga Univ., Spokane, WA (United States)

1995-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "vlf electromagnetic investigations" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


461

Finding Source of Electromagnetic Interference (EMI) to GPS Using a Network Sensors  

E-Print Network [OSTI]

Finding Source of Electromagnetic Interference (EMI) to GPS Using a Network Sensors Shau-Shiun Jan, Per Enge Department of Aeronautics and Astronautics Stanford University ABSTRACT Any electromagnetic interference (EMI) to GPS must invoke a fast location and removal response, because of the high military

Stanford University

462

Experimental and numerical evaluation of electromagnetic acoustic transducer performance on steel materials  

E-Print Network [OSTI]

Experimental and numerical evaluation of electromagnetic acoustic transducer performance on steel 2011 Keywords: Electromagnetic Acoustic Transducers Magnetostriction Lorentz force Steel a b s t r a c of the test object. A wide variety of steel materials is employed in many industrial applications, so

Nagy, Peter B.

463

The electromagnetic fields and the radiation of a spatio-temporally varying electric current loop  

E-Print Network [OSTI]

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.

Markus Lazar

2013-04-12T23:59:59.000Z

464

High order asymptotics for the electromagnetic scattering from thin periodic layers : the 3D  

E-Print Network [OSTI]

High order asymptotics for the electromagnetic scattering from thin periodic layers : the 3D of electromagnetic waves by a thin periodic layer made of an array of regularly-spaced obstacles. The size, they satisfy electrostatic problems posed in an infinite 3D strip that require a careful analysis. Error

Boyer, Edmond

465

Twisted electromagnetic beams Swedish Institute of Space Physics and Uppsala University  

E-Print Network [OSTI]

Twisted electromagnetic beams Swedish Institute of Space Physics and Uppsala University of freedom for the radiation. Electromagnetic beams that carry OAM appear twisted. The twist can be used more information than with regular beams. Even single photons can carry a twist, in addition

466

Progress In Electromagnetics Research, PIER 74, 119, 2007 ANALYSIS OF INTERACTION BETWEEN A  

E-Print Network [OSTI]

partially re-radiates, and partially dissipates within the FR body, eventually producing heat. Both re-radiated energy and heat loss in the FR depend on coupling between the FR and the electromagnetic field picks out energy from electromagnetic field at the ferromagnetic resonance. Thus the typical linewidth

Koledintseva, Marina Y.

467

Electromagnetic modeling of the energy distribution of a metallic cylindrical parabolic reflector covered with a magnetized plasma layer  

SciTech Connect (OSTI)

The energy distribution along the focal axis of a long metallic cylindrical parabolic reflector with a plasma layer on its surface in the presence of an external magnetic field is investigated. The effects of some physical parameters, such as the plasma frequency, the wave frequency and the thickness of plasma layer on the energy distribution and the reflected and transmitted electromagnetic fields, are simulated. These investigations for both S- and P-polarizations have been done separately. It is found that the maximum value of the reflected intensity increases by increasing the incident wave frequency and by decreasing the plasma layer thickness and the plasma frequency for both polarizations. Furthermore, the results show that the increase of the magnetic field strength can cause an increase in the reflected intensity for S-polarization and a slight decrease for P-polarization.

Niknam, A. R., E-mail: a-niknam@sbu.ac.ir; Khajehmirzaei, M. R. [Laser and Plasma Research Institute, Shahid Beheshti University, GC, Tehran (Iran, Islamic Republic of); Davoudi-Rahaghi, B.; Rahmani, Z.; Jazi, B.; Abdoli-Arani, A. [Department of Laser and Photonics, Faculty of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

2014-07-15T23:59:59.000Z

468

Low-frequency absorption cross section of the electromagnetic waves for the extreme Reissner-Nordstrom black holes in higher dimensions  

E-Print Network [OSTI]

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.

Luis C. B. Crispino; Atsushi Higuchi; George E. A. Matsas

2010-12-16T23:59:59.000Z

469

Feasibility and electromagnetic compatibility study of the ClearPEM front-end electronics for simultaneous PET-MR imaging  

E-Print Network [OSTI]

electromagnetic interference (EMI) effects between both systems were evaluated on a 7 T magnet by characterizing. Materials and methods The mutual electromagnetic interference tests between Clear- PEM front-end electronics

Dalang, Robert C.

470

Breathers in Josephson junction ladders: Resonances and electromagnetic wave spectroscopy A. E. Miroshnichenko, S. Flach, and M. V. Fistul  

E-Print Network [OSTI]

Breathers in Josephson junction ladders: Resonances and electromagnetic wave spectroscopy A. E localized states discrete breathers and linear electromagnetic excitations EE's in Josephson junction lattices 6 , and localized resistive states in Josephson junction arrays 7­10 . The latter systems

Flach, Sergej

471

arXiv:nucl-ex/0002003v225Feb2000 Phenomenology of the deuteron electromagnetic form factors  

E-Print Network [OSTI]

arXiv:nucl-ex/0002003v225Feb2000 Phenomenology of the deuteron electromagnetic form factors D. The parameterizations allow a phenomenological characterization of the deuteron electromagnetic struc- ture. They can

Thomas Jefferson National Accelerator Facility

472

Geophysical investigation of the ``Thimble,`` 100-H Area  

SciTech Connect (OSTI)

This report summarizes the results of the geophysical investigations conducted as part of the characterization of the buried ``Thimble`` site. The site is located just south of the 116-H-2 Crib and is in the 100-HR-2 Operable Unit. Available documentation has it located between, and at the convergence of, two railroad spurs that run north-south. A concrete monument is believed to mark the site. The burial ground is suspected of containing a vertical safety rod thimble that is reportedly 40 ft long. Ground-penetrating radar (GPR) and electromagnetic induction (EMI) were the two techniques used in the investigation. The methods were selected because they are non-intrusive, relatively fast, economical, and have been used successfully in other similar investigations on the Hanford Site. The objective of the investigation was to locate the buried thimble.

Bergstrom, K.A.

1994-07-08T23:59:59.000Z

473

3-D Finite Element Electromagnetic and Stress Analyses of the JET LB-SRP Divertor Element (Tungsten Lamella Design)  

E-Print Network [OSTI]

3-D Finite Element Electromagnetic and Stress Analyses of the JET LB-SRP Divertor Element (Tungsten Lamella Design)

474

Use of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung*  

E-Print Network [OSTI]

Use of fly ash as an admixture for electromagnetic interference shielding Jingyao Cao, D.D.L. Chung The use of fly ash as an admixture results in enhancement of the electromagnetic interference (EMI of fly ash as an admixture for enhancing the electromagnetic interference (EMI) shielding. EMI shielding

Chung, Deborah D.L.

475

Progress In Electromagnetics Research, Vol. 140, 297311, 2013 SIMPLE, TAYLOR-BASED WORST-CASE MODEL FOR  

E-Print Network [OSTI]

) is resolving unwanted electromagnetic interactions between electronic systems. The number of possibleProgress In Electromagnetics Research, Vol. 140, 297­311, 2013 SIMPLE, TAYLOR-BASED WORST Rennes Cedex 7, France Abstract--To obtain Electromagnetic Compatibility (EMC), we would like to study

Boyer, Edmond

476

ccsd-00013234,version1-5Nov2005 On the physical meaning of the gauge conditions of Classical Electromagnetism  

E-Print Network [OSTI]

Electromagnetism : the hydrodynamics analogue viewpoint Germain Rousseaux Physique et M´ecanique des Milieux H novembre 2005) Based on an analogy between Fluid Mechanics and Electromagnetism, we claim that the gauge conditions of Classical Electromagnetism are not equivalent contrary to the common belief. These "gauges

Paris-Sud XI, Université de

477

Electromagnetic radiation in a time-varying background medium  

E-Print Network [OSTI]

Analytical solutions are presented for the electromagnetic radiation by an arbitrary pulsed source into a homogeneous time-varying background medium. In the constant-impedance case an explicit radiation formula is obtained for the synchronous permittivity and permeability described by any positive function of time. As might be expected, such a medium introduces significant spectral shifts and spatio-temporal modulation, which are analized here for the linear and exponential time-variations of the medium parameters. In the varying-impedance case the solution is obtained for the fourth-order polynomial time-dependence of the permittivity. In addition to the spectral shifts and modulation this spatially homogeneous medium scatters the field introducing causal echoes at the receiver location.

Budko, Neil V

2009-01-01T23:59:59.000Z

478

Chaotic Emission from Electromagnetic Systems Considering Self-Interaction  

E-Print Network [OSTI]

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.

Fernando Kokubun; Vilson T. Zanchin

2006-05-02T23:59:59.000Z

479

Flavor decomposition of the elastic nucleon electromagnetic form factors  

SciTech Connect (OSTI)

The u- and d-quark contributions to the elastic nucleon electromagnetic form factors have been determined using experimental data on GEn , GMn , GpE , and GpM . Such a flavor separation of the form factors became possible up to 3.4 GeV2 with recent data on GEn from Hall A at JLab. At a negative four-momentum transfer squared Q2 above 1 GeV2, for both the u- and d-quark components, the ratio of the Pauli form factor to the Dirac form factor, F2/F1, was found to be almost constant, and for each of F2 and F1 individually, the d-quark component drops continuously with increasing Q2.

C.D. Cates, C.W. Jager, S. Riordan, B. Wojtsekhowski

2011-06-01T23:59:59.000Z

480

A current driven electromagnetic mode in sheared and toroidal configurations  

E-Print Network [OSTI]

The induced electric field in a tokamak drives a parallel electron current flow. In an inhomogeneous, finite beta plasma, when this electron flow is comparable to the ion thermal speed, the Alfven mode wave solutions of the electromagnetic gyrokinetic equation can become nearly purely growing kink modes. Using the new "low-flow" version of the gyrokinetic code GS2 developed for momentum transport studies [Barnes et al 2013 Phys. Rev. Lett. 111, 055005], we are able to model the effect of the induced parallel electric field on the electron distribution to study the destabilizing influence of current on stability. We identify high mode number kink modes in GS2 simulations and make comparisons to analytical theory in sheared magnetic geometry. We demonstrate reassuring agreement with analytical results both in terms of parametric dependences of mode frequencies and growth rates, and regarding the radial mode structure.

Pusztai, Istvn; Parra, Felix I; Barnes, Michael

2013-01-01T23:59:59.000Z

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481

The Future of Hard and Electromagnetic Probes at RHIC  

E-Print Network [OSTI]

Potential near- and long-term physics opportunities with jets, heavy flavors and electromagnetic probes at the Relativistic Heavy Ion Collider (RHIC) are presented. Much new physics remains to be unveiled using these probes, due to their sensitivity to the initial high density stage of RHIC collisions, when quark-gluon plasma (QGP) formation is expected. Additional physics will include addressing deconfinement, chiral symmetry restoration, properties of the strongly-coupled QGP and a possible weakly-interacting QGP, color glass condensate in the initial state, and hadronization. To fully realize the physics prospects of the RHIC energy regime, new detector components must be added to existing experiments, the RHIC machine luminosity upgraded, and a possible new detector with significantly extended coverage and capabilities added.

John W. Harris

2005-03-18T23:59:59.000Z

482

Electromagnetic Isolation Solutions in Low Temperature Cofired Ceramic (LTCC)  

SciTech Connect (OSTI)

Low Temperature Cofired Ceramic (LTCC) is a commercial ceramic-glass multilayer technology with compelling advantages for microelectronics, microsystems and sensors. High frequency applications require good electrical properties such as low dielectric loss and newer applications require extreme isolation from electromagnetic interference (EMI) that is even difficult to measure (-150db). Approaches to providing this isolation, once provided by via fences, have included sidewall coating and full tape thickness features (FTTF) that have been introduced by the filling of slots with via-fill compositions. Several techniques for creating these structures have been modeled for stress and temperature effects in the face of other necessary attachments, such as metallic seal frames. The relative effects of attachment media, FTTF geometry, and alternative measures will be reported. Approaches for thick film and thin film implementations are described.

Krueger, Daniel; Peterson, Ken; Euler, Laurie

2011-10-09T23:59:59.000Z

483

From Photons to Atoms - The Electromagnetic Nature of Matter  

E-Print Network [OSTI]

Motivated by a revision of the classical equations of electromagnetism that allow for the inclusion of solitary waves in the solution space, the material collected in these notes examine the consequences of adopting the modified model in the description of atomic structures. The possibility of handling "photons" in a deterministic way opens indeed a chance for reviewing the foundations of quantum physics. Atoms and molecules are described as aggregations of nuclei and electrons joined through organized photon layers resonating at various frequencies, explaining how matter can absorb or emit light quanta. Some established viewpoints are subverted, offering an alternative scenario. The analysis seeks to provide an answer to many technical problems in physical chemistry and, at the same time, to raise epistemological questions.

Daniele Funaro

2012-05-07T23:59:59.000Z

484

Electromagnetic valve for controlling the flow of molten, magnetic material  

DOE Patents [OSTI]

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

Richter, T.

1998-06-16T23:59:59.000Z

485

Measurement of Dicke Narrowing in Electromagnetically Induced Transparency  

E-Print Network [OSTI]

Dicke narrowing is a phenomena that dramatically reduces the Doppler width of spectral lines, due to frequent velocity-changing collisions. A similar phenomena occurs for electromagnetically induced transparency (EIT) resonances, and facilitates ultra-narrow spectral features in room-temperature vapor. We directly measure the Dicke-like narrowing by studying EIT line-shapes as a function of the angle between the pump and the probe beams. The measurements are in good agreement with an analytic theory with no fit parameters. The results show that Dicke narrowing can increase substantially the tolerance of hot-vapor EIT to angular deviations. We demonstrate the importance of this effect for applications such as imaging and spatial solitons using a single-shot imaging experiment, and discuss the implications on the feasibility of storing images in atomic vapor.

M. Shuker; O. Firstenberg; R. Pugatch; A. Ben-Kish; A. Ron; N. Davidson

2007-03-13T23:59:59.000Z

486

Angular dependence of Dicke-narrowed electromagnetically induced transparency resonances  

SciTech Connect (OSTI)

Dicke narrowing is a phenomenon that dramatically reduces the Doppler width of spectral lines, due to frequent velocity-changing collisions. A similar phenomenon occurs for electromagnetically induced transparency (EIT) resonances, and facilitates ultranarrow spectral features in room-temperature vapor. We directly measure the Dicke-like narrowing by studying EIT line shapes as a function of the angle between the pump and probe beams. The measurements are in good agreement with an analytic theory with no fit parameters. The results show that Dicke narrowing can increase substantially the tolerance of hot-vapor EIT to angular deviations. We demonstrate the importance of this effect for applications such as imaging and spatial solitons using a single-shot imaging experiment, and discuss the implications for the feasibility of storing images in atomic vapor.

Shuker, M.; Firstenberg, O.; Ben-Kish, A.; Ron, A. [Department of Physics, Technion-Israel Institute of Technology, Haifa 32000 (Israel); Pugatch, R.; Davidson, N. [Department of Physics of Complex Systems, Weizmann Institute of Science, Rehovot 76100 (Israel)

2007-08-15T23:59:59.000Z

487

Branching Ratio of the Electromagnetic Decay of the ?+(1385)  

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

The CLAS detector was used to obtain the first ever measurement of the electromagnetic decay of the ?*+(1385) from the reaction ?p ? K0 ?*+(1385). A real photon beam with a maximum energy of 3.8 GeV was incident on a liquid-hydrogen target, resulting in the photoproduction of the kaon and ?* hyperon. Kinematic fitting was used to separate the reaction channel from the background processes. The fitting algorithm exploited a new method to kinematically fit neutrons in the CLAS detector, leading to the partial width measurement of 250.0 56.9(stat)-41.2+34.3(sys) keV. A U-spin symmetry test using the SU(3) flavor-multiplet representation yields predictions for the ?*+(1385) ? ?+? and ?*0(1385) ? ?? partial widths that agree with the experimental measurements.

Keller, D; Adhikari, K P; Adikaram, D; Amaryan, M J; Anghinolfi, M; Baghdasaryan, H; Ball, J; Battaglieri, M; Bedlinskiy, I; Biselli, A S; Bookwalter, C; Boiarinov, S; Branford, D; Briscoe, W J; Brooks, W K; Burkert, V D; Carman, D S; Celentano, A; Chandavar, S; Cole, P L; Contalbrigo, M; Crede, V; D' Angelo, A; Daniel, A; Dashyan, N; De Vita, R; De Sanctis, E; Djalali, C; Doughty, D; Dupre, R; El Alaoui, A; El Fassi, L; Elouadrhiri, L; Eugenio, P; Fedotov, G; Gabrielyan, M Y; Gevorgyan, N; Gilfoyle, G P; Giovanetti, K L; Gohn, W; Golovatch, E; Gothe, R W; Graham, L; Griffioen, K A; Guidal, M; Guler, N; Guo, L; Hafidi, K; Hakobyan, H; Holtrop, M; Ilieva, Y; Ireland, D G; Ishkhanov, B S; Isupov, E L; Jo, H S; Joo, K; Khandaker, M; Khertarpal, P; Kim, A; Kim, W; Klein, F J; Kubarovsky, A; Kubarovsky, V; Kuleshov, S V; Lu, H Y; MacGregor, I.J. D; Mao, Y; Markov, N; Mayer, M; McKinnon, B; Meyer, C A; Mirazita, M; Mokeev, V; Moutarde, H; Munevar, E; Nadel-Turonski, P; Nasseripour, R; Niccolai, S; Niculescu, G; Niculescu, I; Osipenko, M; Ostrovidov, A I; Paolone, M; Pappalardo, L; Paremuzyan, R; Anefalos Pereira, S; Pisano, S; Pogorelko, O; Pozdniakov, S; Procureur, S; Prok, Y; Protopopescu, D; Raue, B A; Ricco, G; Rimal, D; Ripani, M; Ritchie, B G; Rosner, G; Rossi, P; Sabatie, F; Saini, M S; Salgado, C; Schott, D; Schumacher, R A; Seraydaryan, H; Sharabian, Y G; Smith, E S; Smith, G D; Sober, D I; Sokhan, D; Stepanyan, S S; Stepanyan, S; Stoler, P; Strauch, S; Taiuti, M; Tang, W; Taylor, C E; Tkachenko, S; Vernarsky, B; Vineyard, M F; Vlassov, A V; Voskanyan, H; Voutier, E; Wood, M H; Zachariou, N; Zana, L; Zhao, B

2012-03-23T23:59:59.000Z

488

Characterization of microstructure with low frequency electromagnetic techniques  

SciTech Connect (OSTI)

A new computational method for characterizing the relationship between surface crystallography and electrical conductivity in anisotropic materials with low frequency electromagnetic techniques is presented. The method is discussed from the standpoint of characterizing the orientation of a single grain, as well as characterizing statistical information about grain ensembles in the microstructure. Large-area electron backscatter diffraction (EBSD) data was obtained and used in conjunction with a synthetic aperture approach to simulate the eddy current response of beta annealed Ti-6Al-4V. Experimental eddy current results are compared to the computed eddy current approximations based on electron backscatter diffraction (EBSD) data, demonstrating good agreement. The detectability of notches in the presence of noise from microstructure is analyzed with the described simulation method and advantages and limitations of this method are discussed relative to other NDE techniques for such analysis.

Cherry, Matthew R.; Sathish, Shamachary [University of Dayton Research Institute, Structural Integrity Division, 300 College Park, Dayton, OH 45469-0020 (United States); Pilchak, Adam L.; Blodgett, Mark P. [Air Force Research Laboratory, Materials and Manufacturing Directorate (AFRL/RXCM), 2230 10th St., WPAFB, OH 45433 (United States); Cherry, Aaron J. [Southwest Ohio Council for Higher Education, 3155 Research Blvd., Suite 204, Dayton, OH 45420-4015 (United States)

2014-02-18T23:59:59.000Z

489

Electromagnetic Contribution to the Proton-Neutron Mass Splitting  

E-Print Network [OSTI]

We study the electromagnetic contribution to the proton-neutron mass splitting by combining lattice simulations and the modified Cottingham sum rule of Walker-Loud, Carlson and Miller. This analysis yields an estimate of the isovector nucleon magnetic polarizability as a function of pion mass. The physical value, obtained by chiral extrapolation to the physical pion mass, is $\\beta_{p-n}=(-1.12 \\pm 0.40)\\times 10^{-4}\\ \\mathrm{fm}^3$, which is in agreement with the empirical result, albeit with a somewhat smaller error. As a result, we find $\\delta M^{\\gamma}_{p-n}=1.04 \\pm 0.11\\ \\mathrm{MeV}$, which represents a significant improvement in precision.

A. W. Thomas; X. G. Wang; R. D. Young

2014-06-18T23:59:59.000Z

490

A graphical electromagnetic simulation laboratory for power systems engineering programs  

SciTech Connect (OSTI)

The recent availability of Electromagnetic Transient Programs with graphical front ends now makes it possible to put together models for circuits and systems in a manner similar to the connection of components in a laboratory. In the past, the non-graphical EMT Programs required considerable expertise in their use and thus distracted the students into the details or simulation. The introduction of a graphical simulation based laboratory into Undergraduate and Graduate Engineering Programs is presented, based on the PSCAD/EMTDC program. The philosophy behind the design of suitable example cases is presented within the framework of an Undergraduate Power Electronics Course, an HVdc Transmission Course and a course on Power System Protection.

Gole, A.M. [Univ. of Manitoba, Winnipeg, Manitoba (Canada)] [Univ. of Manitoba, Winnipeg, Manitoba (Canada); Nayak, O.B. [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada)] [Manitoba HVDC Research Centre, Winnipeg, Manitoba (Canada); Sidhu, T.S.; Sachdev, M.S. [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada)] [Univ. of Saskatchewan, Saskatoon, Saskatchewan (Canada)

1996-05-01T23:59:59.000Z

491

Enhanced ULF electromagnetic activity detected by DEMETER above seismogenic regions  

E-Print Network [OSTI]

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...

Athanasiou, M; David, C; Anagnostopoulos, G

2013-01-01T23:59:59.000Z

492

Modulational instability of electromagnetic waves in a collisional quantum magnetoplasma  

SciTech Connect (OSTI)

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 Schrdinger 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.

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

493

Variational Principles for Constrained Electromagnetic Field and Papapetrou Equation  

E-Print Network [OSTI]

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.

A. T. Muminov

2007-06-28T23:59:59.000Z

494

Relativistic electromagnetic flat top solitons and their stability  

SciTech Connect (OSTI)

The inclusion of ion response in the study of relativistically intense electromagnetic laser pulse propagation in plasma yields certain distinct varieties of single peak solitonic structures. A flat top slow moving structure (for which the various fields have a flat profile over a wide spatial range) is one such solution. A detailed characterization of these solutions along with the eigen spectrum of their formation in the parameter space has been presented. The evolution of this particular solution is studied in detail with the help of a coupled fluid Maxwell set of equations. The study shows that the flat top solution is unstable. The instability is characterized as the backward Brillouin instability for which the electron quiver velocity plays the role of the effective temperature.

Sundar, Sita; Das, Amita; Saxena, Vikrant; Kaw, Predhiman; Sen, Abhijit [Institute for Plasma Research, Bhat, Gandhinagar-382428 (India)

2011-11-15T23:59:59.000Z

495

Electromagnetic waves and electron anisotropies downstream of supercritical interplanetary shocks  

E-Print Network [OSTI]

We present waveform observations of electromagnetic lower hybrid and whistler waves with f_ci 1.01. Thus, the whistler mode waves appear to be driven by a heat flux instability and cause perpendicular heating of the halo electrons. The lower hybrid waves show a much weaker correlation between \\partialB and normalized heat flux magnitude and are often observed near magnetic field gradients. A third type of event shows fluctuations consistent with a mixture of both lower hybrid and whistler mode waves. These results suggest that whistler waves may indeed be regulating the electron heat flux and the halo temperature anisotropy, which is important for theories and simulations of electron distribution evolution from the sun to the earth.

Wilson, L B; Szabo, A; Breneman, A; Cattell, C A; Goetz, K; Kellogg, P J; Kersten, K; Kasper, J C; Maruca, B A; Pulupa, M

2012-01-01T23:59:59.000Z

496

Electromagnetic Signature Technique as a Promising Tool to Verify Nuclear Weapons Storage and Dismantlement under a Nuclear Arms Control Regime  

SciTech Connect (OSTI)

The 2010 ratification of the New START Treaty has been widely regarded as a noteworthy national security achievement for both the Obama administration and the Medvedev-Putin regime, but deeper cuts are envisioned under future arms control regimes. Future verification needs will include monitoring the storage of warhead components and fissile materials and verifying dismantlement of warheads, pits, secondaries, and other materials. From both the diplomatic and technical perspectives, verification under future arms control regimes will pose new challenges. Since acceptable verification technology must protect sensitive design information and attributes, non-nuclear non-sensitive signatures may provide a significant verification tool without the use of additional information barriers. The use of electromagnetic signatures to monitor nuclear material storage containers is a promising technology with the potential to fulfill these challenging requirements. Research performed at Pacific Northwest National Laboratory (PNNL) has demonstrated that low frequency electromagnetic signatures of sealed metallic containers can be used to confirm the presence of specific components on a yes/no basis without revealing classified information. Arms control inspectors might use this technique to verify the presence or absence of monitored items, including both nuclear and non-nuclear materials. Although additional research is needed to study signature aspects such as uniqueness and investigate container-specific scenarios, the technique potentially offers a rapid and cost-effective tool to verify reduction and dismantlement of U.S. and Russian nuclear weapons.

Bunch, Kyle J.; Williams, Laura S.; Jones, Anthony M.; Ramuhalli, Pradeep

2012-08-01T23:59:59.000Z

497

Semiclassical Estimates of Electromagnetic Casimir Self-Energies of Spherical and Cylindrical Metallic Shells  

E-Print Network [OSTI]

The leading semiclassical estimates of the electromagnetic Casimir stresses on a spherical and a cylindrical metallic shell are within 1% of the field theoretical values. The electromagnetic Casimir energy for both geometries is given by two decoupled massless scalars that satisfy conformally covariant boundary conditions. Surface contributions vanish for smooth metallic boundaries and the finite electromagnetic Casimir energy in leading semiclassical approximation is due to quadratic fluctuations about periodic rays in the interior of the cavity only. Semiclassically the non-vanishing Casimir energy of a metallic cylindrical shell is almost entirely due to Fresnel diffraction.

Martin Schaden

2010-06-16T23:59:59.000Z

498

Electromagnetic Analysis For The Design Of ITER Diagnostic Port Plugs During Plasma Disruptions  

SciTech Connect (OSTI)

ITER diagnostic port plugs perform many functions including structural support of diagnostic systems under high electromagnetic loads while allowing for diagnostic access to plasma. The design of diagnotic equatorial port plugs (EPP) are largely driven by electromagnetic loads and associate response of EPP structure during plasma disruptions and VDEs. This paper summarizes results of transient electromagnetic analysis using Opera 3d in support of the design activities for ITER diagnostic EPP. A complete distribution of disruption loads on the Diagnostic First Walls (DFWs). Diagnostic Shield Modules (DSMs) and the EPP structure, as well as impact on the system design integration due to electrical contact among various EPP structural components are discussed.

Zhai, Y

2014-03-03T23:59:59.000Z

499

On the electromagnetic constitutive laws that are equivalent to spacetime metrics  

E-Print Network [OSTI]

The raising of both indices in the components of the Minkowski electromagnetic field strength 2-form to give the components of the electromagnetic excitation bivector field can be regarded as being equivalent to an electromagnetic constitutive law, as well as being defined by the components of the spacetime metric. This notion is clarified, and the nature of the equivalent dielectric tensors and magnetic permeability tensors that are defined by some common spacetime metrics is discussed. The relationship of the basic construction to effective metrics is discussed, and, in particular, the fact that this effective metric is more general than the Gordon metric.

D. H. Delphenich

2014-09-17T23:59:59.000Z

500

Electromagnetic Radiation in Hot QCD Matter: Rates, Electric Conductivity, Flavor Susceptibility and Diffusion  

E-Print Network [OSTI]

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.

Chang-Hwan Lee; Ismail Zahed

2014-03-07T23:59:59.000Z