The Unified Theory - Electricity, Magnetism, Gravity and Mechanics
Pretterebner Julius
1999-08-12
This article shows the relations between the electricity, magnetism, gravity and mechanics by presenting an existing hidden structure in the Maxwell equations. This hidden structure allows to discover the classical physic from a new point of view leading to the unified theory (UT).
and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Department of Geophysics, Colorado School
Kristofer Davis, M. Andy Kass, and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado
Jiajia Sun and Yaoguo Li, Center for Gravity, Electrical and Magnetic Studies, Colorado School of Mines
for Gravity, Electrical and Magnetic Studies, Colorado School of Mines SUMMARY Inversion based on L2 norm has
Youngjai Kiem; Dahl Park
1996-10-02
We find an analog of the electric-magnetic duality, which is a $Z_2$ transformation between magnetic and electric sectors of the static and rotationally symmetric solutions in a class of (2+1)-dimensional Einstein-Maxwell-Dilaton gravity theories. The theories in our consideration include, in particular, one parameter class of theories continuously connecting the Banados-Teitelboim-Zanelli (BTZ) gravity and the low energy string effective theory. When there is no $U(1)$ charge, we have $O(2)$ or $O(1,1)$ symmetry, depending on a parameter that specifies each theory. Via the $Z_2$ transformation, we obtain exact magnetically charged solutions from the known electrically charged solutions. We explain the relationship between the $Z_2$ transformation and $O(2,Z)$ symmetry, and comment on the $T$-duality of the string theory.
for Gravity, Electrical, and Magnetics, Colorado School of Mines, Golden, Colorado SUMMARY Recently3D joint inversion of gradient and total-field magnetic data Kristofer Davis and Yaoguo Li, Center and demonstrate it with a synthetic and field example. INTRODUCTION Airborne magnetic gradiometry data
, and wavelets Kristofer Davis and Yaoguo Li, Center for Gravity, Electrical, and Magnetics, Colorado SchoolEfficient 3D inversion of magnetic data via octree mesh discretization, space-filling curves
Holographic Aspects of Electric-Magnetic Dualities
Sebastian de Haro; Anastasios C. Petkou
2007-10-04
We review recent work on holographic aspects of electric-magnetic dualities in theories that involve conformally coupled scalars and abelian gauge fields in asymptotically AdS4 spaces. Such models are relevant for the holographic description of M-theory. We also briefly comment on some new results on the holographic properties of generalized electric-magnetic duality in gravity.
LABORATORY VI ELECTRICITY FROM MAGNETISM
Minnesota, University of
LABORATORY VI ELECTRICITY FROM MAGNETISM Lab VI - 1 In the previous problems you explored the magnetic field and its effect on moving charges. You also saw how electric currents could create magnetic can give rise to electric currents. This is the effect that allows the generation of electricity
Noise in the processing and application of magnetic gradients Leon Foks, Kristofer Davis SUMMARY The increased use of magnetic gradients brings about the need for reliable noise characterization to characterize noise in magnetic gradient data. We use an equivalent source technique and finite differ- ence
Application of magnetic amplitude inversion in exploration for natural gas in volcanics Yaoguo Li basins and have strong remanent magnetization. The appli- cation arises in exploration of natural gas identify the volcanic units at large depths. INTRODUCTION Exploration for natural gas hosted in volcanics
LABORATORY VI ELECTRICITY FROM MAGNETISM
Minnesota, University of
LABORATORY VI ELECTRICITY FROM MAGNETISM Lab VI - 1 In the previous problems you explored by electric currents. This lab will carry that investigation one step further, determining how changing magnetic fields can give rise to electric currents. This is the effect that allows the generation
Magnetic Fields Analogous to electric field, a magnet
Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University
Magnetic Fields Analogous to electric field, a magnet produces a magnetic field, B Set up a B field two ways: Moving electrically charged particles Current in a wire Intrinsic magnetic field Basic) Opposite magnetic poles attract like magnetic poles repel #12;Like the electric field lines
Geologic interpretation of gravity and magnetic data in the Salida...
Geologic interpretation of gravity and magnetic data in the Salida region, Colorado Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Geologic...
Anisotropy of magnetic emulsions induced by magnetic and electric fields
Yury I. Dikansky; Alexander N. Tyatyushkin; Arthur R. Zakinyan
2011-09-10
The anisotropy of magnetic emulsions induced by simultaneously acting electric and magnetic fields is theoretically and experimentally investigated. Due to the anisotropy, the electric conductivity and magnetic permeability of a magnetic emulsion are no longer scalar coefficients, but are tensors. The electric conductivity and magnetic permeability tensors of sufficiently diluted emulsions in sufficiently weak electric and magnetic fields are found as functions of the electric and magnetic intensity vectors. The theoretically predicted induced anisotropy was verified experimentally. The experimental data are analyzed and compared with theoretical predictions. The results of the analysis and comparison are discussed.
Electric Field Control of Ferromagnetism and Magnetic Devices Using Multiferroics
Heron, John Thomas
2013-01-01
connections between electricity and magnetism were revealedunderstand that both electricity and magnetism result from aconnections between electricity and magnetism, have largely
Electric-Magnetic Duality in Supergravity
Bernard de Wit
2001-06-11
I review electric-magnetic duality from the perspective of extended supergravity theories in four spacetime dimensions
Electric and Magnetic Walls on Dielectric Interfaces
Changbiao Wang
2010-07-20
Sufficient conditions of the existence of electric or magnetic walls on dielectric interfaces are given for a multizone uniform dielectric waveguiding system. If one of two adjacent dielectric zones supports a TEM field distribution while the other supports a TM (TE) field distribution, then the common dielectric interface behaves as an electric (magnetic) wall, that is, the electric (magnetic) field line is perpendicular to the interface while the magnetic (electric) field line is parallel to the interface.
When electric charge becomes also magnetic
Tiago C. Adorno; Dmitry M. Gitman; Anatoly E. Shabad
2015-07-08
In nonlinear electrodynamics, QED included, we find a static solution to the field equations with an electric charge as its source, which is comprised of homogeneous parallel magnetic and electric fields, and a radial spherically-nonsymmetric long-range magnetic field, whose magnetic charge is proportional to the electric charge and also depends on the homogeneous component of the solution.
ECE 390 Electric & Magnetic Fields Catalog Description: Static and quasi-static electric's and Laplace's equations. Boundary value problems, method of images · Steady electric currents, static magnetic, students will be able to... 1. Identify the characteristics of static electric and magnetic fields in free
Electric/magnetic field sensor
Schill, Jr., Robert A. (Henderson, NV); Popek, Marc [Las Vegas, NV
2009-01-27
A UNLV novel electric/magnetic dot sensor includes a loop of conductor having two ends to the loop, a first end and a second end; the first end of the conductor seamlessly secured to a first conductor within a first sheath; the second end of the conductor seamlessly secured to a second conductor within a second sheath; and the first sheath and the second sheath positioned adjacent each other. The UNLV novel sensor can be made by removing outer layers in a segment of coaxial cable, leaving a continuous link of essentially uncovered conductor between two coaxial cable legs.
Electric Dipole Moment of Magnetic Monopole
Makoto Kobayashi
2007-03-07
The electric dipole moment of magnetic monopoles with spin is studied in the N=2 supersymmetric gauge theory. The dipole moments of the electric charge distributions, as well as the dipole moments due to the magnetic currents, are calculated. The contribution of charge distribution of the fermion to the gyroelectric ratio is expressed by using zeta(3).
Center for Gravity, Electrical & Magnetic Studies
and accentuates mid-frequency signals and produces a data set with more resolving power than total-field data-field data acquired from aeromagnetic surveys as independent data sets for quantitative interpretation. These approaches treat the observed gradients as an additional and independent data set rather than just
Electrical properties of chain microstructure magnetic emulsions in magnetic field
Arthur Zakinyan; Yuri Dikansky; Marita Bedzhanyan
2014-02-05
The work deals with the experimental study of the emulsion whose dispersion medium is a magnetic fluid while the disperse phase is formed by a glycerin-water mixture. It is demonstrated that under effect of a magnetic field chain aggregates form from the disperse phase drops. Such emulsion microstructure change affects its macroscopic properties. The emulsion dielectric permeability and specific electrical conductivity have been measured. It is demonstrated that under the effect of relatively weak external magnetic fields (~ 1 kA/m) the emulsion electrical parameters may change several fold. The work theoretically analyzes the discovered regularities of the emulsion electrical properties.
Electric Magnetic Duality in String Theory
Ashoke Sen
1992-10-06
The electric-magnetic duality transformation in four dimensional heterotic string theory discussed by Shapere, Trivedi and Wilczek is shown to be an exact symmetry of the equations of motion of low energy effective field theory even after including the scalar and the vector fields, arising due to compactification, in the effective field theory. Using this duality transformation we construct rotating black hole solutions in the effective field theory carrying both, electric and magnetic charges. The spectrum of extremal magnetically charged black holes turns out to be similar to that of electrically charged elementary string excitations. We also discuss the possibility that the duality symmetry is an exact symmetry of the full string theory under which electrically charged elementary string excitations get exchanged with magnetically charged soliton like solutions. This proposal might be made concrete following the suggestion of Dabholkar et. al. that fundamental strings may be regarded as soliton like classical solutions in the effective field theory.
Electric-Magnetic Duality and WDVV Equations
B. de Wit; A. Marshakov
2001-06-11
We consider the associativity (or WDVV) equations in the form they appear in Seiberg-Witten theory and prove that they are covariant under generic electric-magnetic duality transformations. We discuss the consequences of this covariance from various perspectives.
Can (Electric-Magnetic) Duality Be Gauged?
Claudio Bunster; Marc Henneaux
2014-03-13
There exists a formulation of the Maxwell theory in terms of two vector potentials, one electric and one magnetic. The action is then manifestly invariant under electric-magnetic duality transformations, which are rotations in the two-dimensional internal space of the two potentials, and local. We ask the question: can duality be gauged? The only known and battled-tested method of accomplishing the gauging is the Noether procedure. In its decanted form, it amounts to turn on the coupling by deforming the abelian gauge group of the free theory, out of whose curvatures the action is built, into a non-abelian group which becomes the gauge group of the resulting theory. In this article, we show that the method cannot be successfully implemented for electric-magnetic duality. We thus conclude that, unless a radically new idea is introduced, electric-magnetic duality cannot be gauged. The implication of this result for supergravity is briefly discussed.
Chapter 8 Electric and Magnetic Fields
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
values, Chapter 8 Electric and Magnetic Fields I-5 Corridor Reinforcement Project Draft EIS 8-11 November 2012 Table 8-2 West Alternative and Options-Length-Weighted Average...
Electricity and Magnetism Review Notes by L. Qian1
Qian, Li
Electricity and Magnetism Review Notes by L. Qian1 Electric Magnetic) --------------------------------------------------- ------------------------------------------------- Electric Field: Magnetic Field: Symbol: E r Symbol: B r Unit: V/m = N/C Unit: T = Ns /(Cm) [T: Tesla] - Electric field due to a static charge q - Magnetic field due to a current element sdi r r r q E ^ 4 1 2 0 r
Electric-Magnetic Dualities in Gauge Theories
Ho, Jun-Kai
2015-01-01
Electric-magnetic dualities are equivalence between strong and weak coupling constants. A standard way is to exchange electric and magnetic fields in the abelian gauge theory. We use three ways to perform electric-magnetic dualities in the case of the non-commutative $U(1)$ gauge theory. The first way is to use covariant field strengths to be the electric and magnetic fields. We find an invariant form of the equation of motion after performing the electric-magnetic duality. The second way is to use the Seiberg-Witten map to rewrite the non-commutative $U(1)$ gauge theory in terms of abelian field strength. The third way is that we use the large Neveu Schwarz-Neveu Schwarz (NS-NS) background limit (non-commutativity parameter only has one degree of freedom) to consider the non-commutative $U(1)$ gauge theory or D3-brane. In this limit, we introduce or dualize a new one-form gauge potential to get a D3-brane in a large Ramond-Ramond (R-R) background via field redefinition. We also use perturbation to study equi...
Electric-Magnetic Dualities in Gauge Theories
Jun-Kai Ho; Chen-Te Ma
2015-07-28
Electric-magnetic dualities are equivalence between strong and weak coupling constants. A standard way is to exchange electric and magnetic fields in the abelian gauge theory. We use three ways to perform electric-magnetic dualities in the case of the non-commutative $U(1)$ gauge theory. The first way is to use covariant field strengths to be the electric and magnetic fields. We find an invariant form of the equation of motion after performing the electric-magnetic duality. The second way is to use the Seiberg-Witten map to rewrite the non-commutative $U(1)$ gauge theory in terms of abelian field strength. The third way is that we use the large Neveu Schwarz-Neveu Schwarz (NS-NS) background limit (non-commutativity parameter only has one degree of freedom) to consider the non-commutative $U(1)$ gauge theory or D3-brane. In this limit, we introduce or dualize a new one-form gauge potential to get a D3-brane in a large Ramond-Ramond (R-R) background via field redefinition. We also use perturbation to study equivalence between two D3-brane theories. Comparison on three methods in the non-commutative $U(1)$ gauge theory gives different physical implications. This comparison reflects differences between the non-abelian and non-commutative gauge theories in the electric-magnetic dualities. For a complete study, we also extend our studies to the simplest abelian and non-abelian $p$-form gauge theories, and a non-commutative theory with the non-abelian structure.
Magnetic Braiding and Parallel Electric Fields
A. L. Wilmot-Smith; G. Hornig; D. I. Pontin
2008-10-08
The braiding of the solar coronal magnetic field via photospheric motions - with subsequent relaxation and magnetic reconnection -- is one of the most widely debated ideas of solar physics. We readdress the theory in the light of developments in three-dimensional magnetic reconnection theory. It is known that the integrated parallel electric field along field lines is the key quantity determining the rate of reconnection, in contrast with the two-dimensional case where the electric field itself is the important quantity. We demonstrate that this difference becomes crucial for sufficiently complex magnetic field structures. A numerical method is used to relax a braided magnetic field to an ideal force-free equilibrium; that equilibrium is found to be smooth, with only large- scale current structures. However, the equilibrium is shown to have a highly filamentary integrated parallel current structure with extremely short length- scales. An analytical model is developed to show that, in a coronal situation, the length scales associated with the integrated parallel current structures will rapidly decrease with increasing complexity, or degree of braiding, of the magnetic field. Analysis shows the decrease in these length scales will, for any finite resistivity, eventually become inconsistent with the stability of a force- free field. Thus the inevitable consequence of the magnetic braiding process is shown to be a loss of equilibrium of the coronal field, probably via magnetic reconnection events.
Wikswo, John
Correlation and comparison of magnetic and electric detection of small intestinal electrical? Wikswo, Jr., and William 0. Richards. Correlation and comparison of magnetic and electric detection, the effects of an electrical insulator on the external electric and magnetic fields were studied in the rabbit
Electric-Magnetic Duality Invariant Lagrangians
Machiko Hatsuda; Kiyoshi Kamimura; Sayaka Sekiya
1999-08-24
We find general non-linear lagrangians of a U(1) field invariant under electric-magnetic duality. They are characterized by an arbitrary function and go to the Maxwell theory in the weak field limit. We give some explicit examples which are generalizations of the Born-Infeld theory.
Magnetic response enhancement via electrically induced magnetic moments
B. Jungnitsch; J. Evers
2008-04-22
The realization of negative refraction in atomic gases requires a strong magnetic response of the atoms. Current proposals for such systems achieve an enhancement of the magnetic response by a suitable laser field configuration, but still rely on high gas densities. Thus further progress is desirable, and this requires an understanding of the precise mechanism for the enhancement. Therefore, here we study the magnetic and electric response to a probe field interacting with three-level atoms in ladder configuration. In our first model, the three transitions are driven by a control field and the electric and magnetic component of the probe field, giving rise to a closed interaction loop. In a reference model, the coherent driving is replaced by an incoherent pump field. A time-dependent analysis of the closed-loop system enables us to identify the different contributions to the medium response. A comparison with the reference system then allows one to identify the physical mechanism that leads to the enhancement. It is found that the enhancement occurs at so-called multiphoton resonance by a scattering of the coupling field and the electric probe field mode into the magnetic probe field mode. Based on these results, conditions for the enhancement are discussed.
Electric-Magnetic Duality in Massless QED?
Chris Ford
2009-09-09
The possibility that QED and recently developed non-Hermitian, or magnetic, versions of QED are equivalent is considered. Under this duality the Hamiltonians and anomalous axial currents of the two theories are identified. A consequence of such a duality is that particles described by QED carry magnetic as well as electric charges. The proposal requires a vanishing zero bare fermion mass in both theories; Dirac mass terms are incompatible with the conservation of magnetic charge much as Majorana masses spoil the conservation of electric charge. The physical spectrum comprises photons and massless spin-1/2 particles carrying equal or opposite electric and magnetic charges. The four particle states described by the Dirac fermion correspond to the four possible charge assignments of elementary dyons. This scale invariant spectrum indicates that the quantum field theory is finite. The Johnson Baker Willey eigenvalue equation for the fine structure constant in finite spinor QED is interpreted as a Dirac-like charge quantisation condition for dyons.
SPECTRAL PROBLEMS FOR OPERATORS WITH CROSSED MAGNETIC AND ELECTRIC FIELDS
Petkov, Vesselin
SPECTRAL PROBLEMS FOR OPERATORS WITH CROSSED MAGNETIC AND ELECTRIC FIELDS MOUEZ DIMASSI Consider the two-dimensional Schr¨odinger operator with homogeneous magnetic and electric fields H = H and > 0 are proportional to the strength of the homogeneous magnetic and electric fields and V (x, y
2.6 ELECTRIC AND MAGNETIC FIELDS Introduction
California at Santa Cruz, University of
325 Â§2.6 ELECTRIC AND MAGNETIC FIELDS Introduction In electromagnetic theory the mks system MKS units Replacement symbol GAUSSIAN units E (Electric field) volt/m E statvolt/cm B (Magnetic field gauss-cm V (Electric potential) volt V statvolt (Dielectric constant) 4 Âµ (Magnetic permeability) 4Âµ c2
Full 180u Magnetization Reversal with Electric Fields
Chen, Long-Qing
Full 180u Magnetization Reversal with Electric Fields J. J. Wang1 *, J. M. Hu1,2 *, J. Ma1 , J. X reversal with an electric field rather than a current or magnetic field is a fundamental challenge morphological engineering approach to accomplishing full 1806 magnetization reversals with electric fields
Lorentz and "apparent" transformations of the electric and magnetic fields
Tomislav Ivezic
2006-07-21
It is recently discovered that the usual transformations of the three-dimensional (3D) vectors of the electric and magnetic fields differ from the Lorentz transformations (LT) (boosts) of the corresponding 4D quantities that represent the electric and magnetic fields. In this paper, using geometric algebra formalism, this fundamental difference is examined representing the electric and magnetic fields by bivectors.
ELECTRICALLY AND MAGNETICALLY CHARGED VORTICES IN THE CHERNSIMONSHIGGS THEORY
Spirn, Daniel
ELECTRICALLY AND MAGNETICALLY CHARGED VORTICES IN THE CHERNÂSIMONSÂHIGGS THEORY ROBIN MING CHEN explored the idea of Dirac and proposed the existence of both electrically and magnetically charged electric and magnetic charges of a dyon. In modern theoretical physics, dyons are consid- ered as excited
Magnetic and electric excitations in split ring resonators
Magnetic and electric excitations in split ring resonators Jiangfeng Zhou1,2,, Thomas Koschny1 studied the electric and magnetic resonances of U-shaped SRRs. We showed that higher order excitation modes exist in both of the electric and magnetic resonances. The nodes in the current distribution were
Magnetic flowmeter for electrically conductive liquid
Skladzien, Stanley B. (Elmhurst, IL); Raue, Donald J. (Naperville, IL)
1982-01-01
A magnetic flowmeter includes first and second tube sections each having ls of non-magnetic material. The first tube is suitably connected to a process for passing a flow of an electrically conductive fluid to be measured. The second tube is established as a reference containing a still medium and is maintained at the same temperature as the first tube. A rotatable magnet assembly is disposed between the two tubes with at least two magnets attached to radially extending arms from a central shaft. Each magnet includes an air gap suitably sized to pass astraddle the diameter along a portion of the length of each of the two tubes. The magnets are provided in matched pairs spaced 180.degree. apart such that signals will be simultaneously generated in signal leads attached to each of the two tubes. By comparing the signals from the two tubes and varying the rotating speed of the magnet assembly until the signals are equal, or attain a maximum, the flow velocity of the fluid within the first tube can be determined. Through temperature monitoring and appropriate heaters, the two tubes are maintained at the same temperature.
California at Berkeley, University of
Quantitative estimates of magnetic field reconnection properties from electric and magnetic field there are positive electric field components tangential to the magnetopause and a magnetic field component normal to it. Because these three components are the smallest of the six electric and magnetic fields
2.6 ELECTRIC AND MAGNETIC FIELDS Introduction
California at Santa Cruz, University of
325 Â§2.6 ELECTRIC AND MAGNETIC FIELDS Introduction In electromagnetic theory the mks system MKS units Replacement symbol GAUSSIAN units # E (Electric field) volt/m # E statvolt/cm # B (Magnetic Magnetic field) ampere/m c # H 4# oersted # J (Current density) ampere/m 2 # J statampere/cm 2 # A (Vector
Ceramic electrical insulation for electrical coils, transformers, and magnets
Rice, John A. (Longmont, CO); Hazelton, Craig S. (Lafayette, CO); Fabian, Paul E. (Broomfield, CO)
2002-01-01
A high temperature electrical insulation is described, which is suitable for electrical windings for any number of applications. The inventive insulation comprises a cured preceramic polymer resin, which is preferably a polysiloxane resin. A method for insulating electrical windings, which are intended for use in high temperature environments, such as superconductors and the like, advantageously comprises the steps of, first, applying a preceramic polymer layer to a conductor core, to function as an insulation layer, and second, curing the preceramic polymer layer. The conductor core preferably comprises a metallic wire, which may be wound into a coil. In the preferred method, the applying step comprises a step of wrapping the conductor core with a sleeve or tape of glass or ceramic fabric which has been impregnated by a preceramic polymer resin. The inventive insulation system allows conducting coils and magnets to be fabricated using existing processing equipment, and maximizes the mechanical and thermal performance at both elevated and cryogenic temperatures. It also permits co-processing of the wire and the insulation to increase production efficiencies and reduce overall costs, while still remarkably enhancing performance.
Electric Flux Tube in Magnetic Plasma
Jinfeng Liao; Edward Shuryak
2007-12-06
In this paper we study a methodical problem related to the magnetic scenario recently suggested and initiated by the authors \\cite{Liao_ES_mono} to understand the strongly coupled quark-gluon plasma (sQGP): the electric flux tube in monopole plasma. A macroscopic approach, interpolating between Bose condensed (dual superconductor) and classical gas medium is developed first. Then we work out a microscopic approach based on detailed quantum mechanical calculation of the monopole scattering on electric flux tube, evaluating induced currents for all partial waves. As expected, the flux tube looses its stability when particles can penetrate it: we make this condition precise by calculating the critical value for the product of the flux tube size times the particle momentum, above which the flux tube dissolves. Lattice static potentials indicate that flux tubes seem to dissolve at $T>T_{dissolution} \\approx 1.3 T_c$. Using our criterion one gets an estimate of the magnetic density $n\\approx 4.4 \\sim 6.6 fm^{-3}$ at this temperature.
Electric-magnetic duality implies (global) conformal invariance
Sung-Pil Moon; Sang-Jin Lee; Ji-Hye Lee; Jae-Hyuk Oh
2014-05-30
We have examined quantum theories of electric magnetic duality invariant vector fields enjoying classical conformal invariance in 4-dimensional flat spacetime. We extend Dirac's argument about "the conditions for a quantum field theory to be relativistic" to "those for a quantum theory to be conformal". We realize that electric magnetic duality invariant vector theories together with classical conformal invariance defined in 4-$d$ flat spacetime are still conformally invariant theories when they are quantized in a way that electric magnetic duality is manifest.
Calculation Method of Permanent Magnet Pickups for Electric Guitars
Paris-Sud XI, UniversitÃ© de
in the 1930s, when Rickenbacker fitted out a guitar with a magnet and coils, thus designing the first magnetic to look at the types of magnetic circuit for the guitar pickups. We consider in this paper the most usual1 Calculation Method of Permanent Magnet Pickups for Electric Guitars G. Lemarquand and V
Schroedinger operators with singularly scaled magnetic and electric potentials
Yuriy Golovaty
2013-09-02
The norm resolvent convergence of a family of one-dimensional Schroedinger operators with singular magnetic and electric potentials of small support is studied.
All-electrical manipulation of magnetization dynamics in a ferromagnet...
Office of Scientific and Technical Information (OSTI)
All-electrical manipulation of magnetization dynamics in a ferromagnet by antiferromagnets with anisotropic spin Hall effects Citation Details In-Document Search This content will...
Thermal to electricity conversion using thermal magnetic properties
West, Phillip B [Idaho Falls, ID; Svoboda, John [Idaho Falls, ID
2010-04-27
A system for the generation of Electricity from Thermal Energy using the thermal magnetic properties of a Ferromagnetic, Electrically Conductive Material (FECM) in one or more Magnetic Fields. A FECM is exposed to one or more Magnetic Fields. Thermal Energy is applied to a portion of the FECM heating the FECM above its Curie Point. The FECM, now partially paramagnetic, moves under the force of the one or more Magnetic Fields. The movement of the FECM induces an electrical current through the FECM, generating Electricity.
Scattering Polarization in the Presence of Magnetic and Electric Fields
Yee Yee Oo; M. Sampoorna; K. N. Nagendra; Sharath Ananthamurthy; G. Ramachandran
2007-02-12
The polarization of radiation by scattering on an atom embedded in combined external quadrupole electric and uniform magnetic fields is studied theoretically. Limiting cases of scattering under Zeeman effect and Hanle effect in weak magnetic fields are discussed. The theory is general enough to handle scattering in intermediate magnetic fields (Hanle-Zeeman effect) and for arbitrary orientation of magnetic field. The quadrupolar electric field produces asymmetric line shifts and causes interesting level-crossing phenomena either in the absence of an ambient magnetic field or in its presence. It is shown that the quadrupolar electric field produces an additional depolarization in the $Q/I$ profiles and rotation of the plane of polarization in the $U/I$ profile over and above that arising from magnetic field itself. This characteristic may have a diagnostic potential to detect steady state and time varying electric fields that surround radiating atoms in Solar atmospheric layers.
Neutron stars in a perturbative f(R) gravity model with strong magnetic fields
Cheoun, Myung-Ki; Deliduman, Cemsinan; Güngör, Can; Kele?, Vildan; Ryu, C.Y.; Kajino, Toshitaka; Mathews, Grant J. E-mail: cemsinan@msgsu.edu.tr E-mail: kelesvi@itu.edu.tr E-mail: kajino@nao.ac.jp
2013-10-01
In Kaluza-Klein electromagnetism it is natural to associate modified gravity with strong electromagnetic fields. Hence, in this paper we investigate the combined effects of a strong magnetic field and perturbative f(R) gravity on the structure of neutron stars. The effect of an interior strong magnetic field of about 10{sup 17?18} G on the equation of state is derived in the context of a quantum hadrodynamics (QHD) equation of state (EoS) including effects of the magnetic pressure and energy along with occupied Landau levels. Adopting a random orientation of interior field domains, we solve the modified spherically symmetric hydrostatic equilibrium equations derived for a gravity model with f(R) = R+?R{sup 2}. Effects of both the finite magnetic field and the modified gravity are detailed for various values of the magnetic field and the perturbation parameter ? along with a discussion of their physical implications. We show that there exists a parameter space of the modified gravity and the magnetic field strength, in which even a soft equation of state can accommodate a large ( > 2 M{sub s}un) maximum neutron star mass.
Fast chirality reversal of the magnetic vortex by electric current
Lim, W. L. Liu, R. H.; Urazhdin, S.; Tyliszczak, T.; Erokhin, S. G.; Berkov, D.
2014-12-01
The possibility of high-density information encoding in magnetic materials by topologically stable inhomogeneous magnetization configurations such as domain walls, skyrmions, and vortices has motivated intense research into mechanisms enabling their control and detection. While the uniform magnetization states can be efficiently controlled by electric current using magnetic multilayer structures, this approach has proven much more difficult to implement for inhomogeneous states. Here, we report direct observation of fast reversal of magnetic vortex by electric current in a simple planar structure based on a bilayer of spin Hall material Pt with a single microscopic ferromagnetic disk contacted by asymmetric electrodes. The reversal is enabled by a combination of the chiral Oersted field and spin current generated by the nonuniform current distribution in Pt. Our results provide a route for the efficient control of inhomogeneous magnetization configurations by electric current.
Remarks on magnetic and electric Aharonov-Bohm effects
Gregory Eskin
2011-09-17
We give a direct proof of the magnetic Aharonov-Bohm effects without using the scattering theory and the theory of inverse boundary value problems. This proof can serve as a framework for a physical experiment to confirm the magnetic AB effect. We prove also the electric AB effect and we suggest a physical experiment to demonstrate the electric AB effect. In addition, we consider a combined electric and magnetic AB effect and we propose a new inverse problem for the time-dependent Schr\\"odinger equations. Finally we study the gravitational AB effect.
Gauge theory of gravity: Electrically charged solutions within the metric--affine framework
Friedrich W. Hehl; José Socorro
1998-03-10
We find a class of electrically charged exact solutions for a toy model of metric-affine gravity. Their metric is of the Pleba\\'nski-Demia\\'nski type and their nonmetricity and torsion are represented by a triplet of covectors with dilation, shear, and spin charges.
Magnetic and Electric Dipole Constraints on Extra Dimensions and Magnetic Fluxes
Aaron J. Roy; Myron Bander
2008-05-10
The propagation of charged particles and gauge fields in a compact extra dimension contributes to $g-2$ of the charged particles. In addition, a magnetic flux threading this extra dimension generates an electric dipole moment for these particles. We present constraints on the compactification size and on the possible magnetic flux imposed by the comparison of data and theory of the magnetic moment of the muon and from limits on the electric dipole moments of the muon, neutron and electron.
Superconducting magnetic energy storage for asynchronous electrical systems
Boenig, H.J.
1984-05-16
It is an object of the present invention to provide superconducting magnetic energy storage for a plurality of asynchronous electrical systems. It is a further object of the present invention to provide load leveling and stability improvement in a plurality of independent ac systems using a single superconducting magnetic energy storage coil.
Yutaka Hosotani; Hiroki Emoto; Takahiro Kubota
2002-09-11
In the SU(2)_L x U(1)_Y standard electroweak theory coupled with the Einstein gravity, new topological configurations naturally emerge, if the spatial section of the universe is globally a three-sphere (S^3) with a small radius. The SU(2)_L gauge fields wrap the space nontrivially, producing homogeneous but anisotropic space. As the universe expands, large electric and magnetic fields are produced. The electromagnetic field configuration is characterized by the Hopf map.
Nature of Electric and Magnetic Fields; How the Fields Transform
Ivezic, Tomislav
2015-01-01
In this paper the proofs are given that the electric and magnetic fields are properly defined vectors on the four-dimensional (4D) spacetime (the 4-vectors in the usual notation) and not the usual 3D fields. Furthermore, the proofs are presented that under the mathematically correct Lorentz transformations (LT), e.g., the electric field vector transforms as any other vector transforms, i.e., again to the electric field vector; there is no mixing with the magnetic field vector B, as in the usual transformations (UT) of the 3D fields. The derivations of the UT from some well-known textbooks are discussed and objected.
Nature of Electric and Magnetic Fields; How the Fields Transform
Tomislav Ivezic
2015-08-10
In this paper the proofs are given that the electric and magnetic fields are properly defined vectors on the four-dimensional (4D) spacetime (the 4-vectors in the usual notation) and not the usual 3D fields. Furthermore, the proofs are presented that under the mathematically correct Lorentz transformations (LT), e.g., the electric field vector transforms as any other vector transforms, i.e., again to the electric field vector; there is no mixing with the magnetic field vector B, as in the usual transformations (UT) of the 3D fields. The derivations of the UT from some well-known textbooks are discussed and objected.
Electric and magnetic fields program overview
1995-09-01
DOE`s EMF Program is presented. The possibility of biological effects from electromagnetic fields created by electricity is examined. Current research at many National Laboratories is reviewed.
Electric-Magnetic Struggle in QGP, Deconfinement and Baryons
Edward Shuryak
2007-09-13
We argue that quite unusual properties of Quark-Gluon Plasma in the RHIC temperature domain $T=(1-2)T_c$ are consequences of the approximate equilibrium between electric and magnetic sectors reached above the deconfinement temperature. Already classical study of few body motion in a electric-magnetic plasma shows abnormally large scattering rate due to the so called ``magnetic bottle'' effect. Molecular dynamics simulation have found that equal mixture of electric and magnetic quasiparticles do produce plasmas of small viscosity and even smaller diffusion rate, comparable to what is needed to explain RHIC data and also to what follows from AdS/CFT. As a separate issue, we point out that right above $T_c$ there should be surviving s-wave baryons made of quarks ($N,\\Delta$), as well as adjoint objects, 3-gluon and 3-monopole chains (the latter being nothing else but ``calorons'' or finite-T instantons).
Saturated nucleate pool boiling of oxygen under magnetically-enhanced effective gravity
T. A. Corcovilos; M. E. Turk; D. M. Strayer; N. N. Asplund; N. -C. Yeh
2007-02-01
We investigate the effect of enhancing gravity on saturated nucleate pool boiling of oxygen for effective gravities of 1g, 6.0g, and 16g (g=9.8 m/s^2) at a saturation pressure of 760 torr and for heat fluxes of 10 ~ 3000 W/m^2. The effective gravity on the oxygen is increased by applying a magnetic body force generated by a superconducting solenoid. We measure the heater temperature (expressed as a reduced superheat) as a function of heat flux and fit this data to a piecewise power-law/linear boiling curve. At low heat flux (<400 W/m^2) the superheat is proportional to the cube root of the heat flux. At higher heat fluxes, the superheat is a linear function of the heat flux. To within statistical uncertainties, which are limited by variations among experimental runs, we find no variation of the boiling curve over our applied gravity range.
Gravity and magnetic anomalies and the deep structure of the Parnaiba cratonic basin, Brazil
Watts, A. B. "Tony"
Gravity and magnetic anomalies and the deep structure of the Parnaiba cratonic basin, Brazil A. B profile across the Parnaiba cratonic basin in NorthEast Brazil. The purpose of this project is to acquire margin of Parnaíba Basin, Brazil. Geophysics 64: 337-356. Ussami N, Cogo de Sa N, Molina EC. 1993
Orthopositronium: "On the possible relation of gravity to electricity"
B. A. Kotov; B. M. Levin; V. I. Sokolov
2006-04-24
The resolve of the 'orthopositronium-lifetime puzzle' needs study of the "isotope anomaly" in gaseous neon and also of the contribution ~ 0.002 of nonperturbative mode into orthopositronium annihilation. The Michigan results (2003) are considered as the first supervision of relation between gravitation and electricity. For the decision of alternative in interpretation of new and former results it is necessary to execute the program of additional measurements.
Dynamics of a dielectric droplet suspended in a magnetic fluid in electric and magnetic fields
Arthur Zakinyan; Elena Tkacheva; Yury Dikansky
2012-03-24
The behavior of a microdrop of dielectric liquid suspended in a magnetic fluid and exposed to the action of electric and magnetic fields is studied experimentally. With increasing electric field, the deformation of droplets into oblate ellipsoid, toroid and curved toroid was observed. At the further increase in the electric field, the bursting of droplets was also revealed. The electrorotation of deformed droplets was observed and investigated. The influence of an additional magnetic field on the droplet dynamics was studied. The main features of the droplet dynamics were interpreted and theoretically examined.
Strongly coupled plasma with electric and magnetic charges
Jinfeng Liao; Edward Shuryak
2006-12-12
A number of theoretical and lattice results lead us to believe that Quark-Gluon Plasma not too far from $T_c$ contains not only electrically charged quasiparticles -- quarks and gluons -- but magnetically charged ones -- monopoles and dyons -- as well. Although binary systems like charge-monopole and charge-dyon were considered in details before in both classical and quantum settings, it is the first study of coexisting electric and magnetic particles in many-body context. We perform Molecular Dynamics study of strongly coupled plasmas with $\\sim 1000$ particles and different fraction of magnetic charges. Correlation functions and Kubo formulae lead to such transport properties as diffusion constant, shear viscosity and electric conductivity: we compare the first two with empirical data from RHIC experiments as well as results from AdS/CFT correspondence. We also study a number of collective excitations in these systems.
Combined Electric and Magnetic Aharonov-Bohm Effects
Samuel Marcovitch; Yakir Aharonov; Tirza Kaufferr; Benni Reznik
2007-09-11
It is well-known that the electric and magnetic Aharonov-Bohm effects may be formally described on equal footing using the four-vector potential in a relativistic framework. We propose an illustrative manifestation of both effects in a single configuration, in which the specific path of the charged particle determines the weight of the electric and magnetic acquired relative phases. The phases can be distinctively obtained in the Coulomb gauge. The scheme manifests the pedagogical lesson that though each of the relative phases is gauge-dependent their sum is gauge-invariant.
New Electric Field in Asymmetric Magnetic Reconnection K. Malakit,1,2
New Electric Field in Asymmetric Magnetic Reconnection K. Malakit,1,2 M. A. Shay,2 P. A. Cassak,3-plane electric field in collisionless asymmetric magnetic reconnection. This electric field, dubbed the ``Larmor permits an electric field that breaks the frozen- in condition and allows magnetic field lines to change
Halgamuge, Malka N.
REVIEW Comparison Between Two Models for Interactions Between Electric and Magnetic Fields Lines; Interaction Models; Biological Effects Introduction Static magnetic and electric fields occur, and strong low-frequency electric or magnetic fields will induce electric currents in the body that lead
Motion of guiding center drift atoms in the electric and magnetic field of a Penning trap
California at San Diego, University of
Motion of guiding center drift atoms in the electric and magnetic field of a Penning trap S. G discusses the motion of the weakly bound atoms in the electric and magnetic field of the plasma and trap in the magnetic and electric field of the trap. Because the binding is so weak, even a modest electric field
On the Electrical and Magnetic Properties of some Indian Spices
Samson. K. Baby; T. E. Girish
2010-12-11
We have made experimental measurements of electrical conductivity, pH and relative magnetic susceptibility of the aqueous solutions of 24 indian spices. The measured values of electrical conductance of these spices are found to be linearly related to their ash content and bulk calorific values reported in literature. The physiological relevance of the pH and diamagnetic susceptibility of spices when consumed as food or medicine will be also discussed.
Electrical gating effects on the magnetic properties of (Ga,Mn)As diluted magnetic semiconductors
Owen, Man Hon Samuel
2010-11-16
. . . . . . . . . . . . . . . . . . . . . . . . . . 62 3.3.1 Cryogenic systems . . . . . . . . . . . . . . . . . . . . . . . . 62 IV 3.3.2 Electrical measurements . . . . . . . . . . . . . . . . . . . . . 63 Resistance vs. temperature . . . . . . . . . . . . . . . . . . . . 64 Magnetic field sweeps... reduces the tendency toward spin-glass freezing. In fact, for a Background 18 Figure 2.5: Magnetization M as a function of magnetic field H for Ga0.97Mn0.03As thin films, measured at 55 K by SQUID for sample No. 1 at the top panel and sample No. 2...
Alexander J. Silenko
2007-10-02
A buildup of the vertical polarization in the resonant electric dipole moment (EDM) experiment [Y. F. Orlov, W. M. Morse, and Y. K. Semertzidis, Phys. Rev. Lett. 96, 214802 (2006)] is affected by a horizontal electric field in the particle rest frame oscillating at a resonant frequency. This field is defined by the Lorentz transformation of an oscillating longitudinal electric field and a uniform vertical magnetic one. The effect of a longitudinal electric field is significant, while the contribution from a magnetic field caused by forced coherent longitudinal oscillations of particles is dominant. The effect of electric field on the spin dynamics was not taken into account in previous calculations. This effect is considerable and leads to decreasing the EDM effect for the deuteron and increasing it for the proton. The formula for resonance strengths in the EDM experiment has been derived. The spin dynamics has been calculated.
Electric-Magnetic Duality in QED Effective Action
W. S. Bae; Y. M. Cho; D. G. Pak
2000-11-22
Recently we have obtained a non-perturbative but convergent series expression of the one loop effective action of QED, and discussed the renormalization of the effective action. In this paper we establish the electric-magnetic duality in the quantum effective action.
Electric and magnetic response of hot QCD matter
T. Steinert; W. Cassing
2014-03-20
We study the electric conductivity as well as the magnetic response of hot QCD matter at various temperatures $T$ and chemical potentials $\\mu_q$ within the off-shell Parton-Hadron-String Dynamics (PHSD) transport approach for interacting partonic systems in a finite box with periodic boundary conditions. The response of the strongly-interacting system in equilibrium to an external electric field defines the electric conductivity $\\sigma_0$ whereas the response to a moderate external magnetic field defines the induced diamagnetic moment $\\mu_L$ ($T, \\mu_q$) as well as the spin susceptibility $\\chi_S(T, \\mu_q)$. We find a sizeable temperature dependence of the dimensionless ratio $\\sigma_0/T$ well in line with calculations in a relaxation time approach for $T_c \\! electric conductivity $\\sigma(\\Omega)$ shows a simple functional form well in line with results from the Dynamical QuasiParticle Model (DQPM). The spin susceptibility $\\chi_S(T,\\mu_q)$ is found to increase with temperature $T$ and to rise $\\sim \\mu_q ^2/T^2$, too. The actual values for the magnetic response of the QGP in the temperature range below 250 MeV show that the QGP should respond diamagnetically in actual ultra-relativistic heavy-ion collisions since the maximal magnetic fields created in these collisions are smaller than $B_c(T)$ which defines a boundary between diamagnetism and paramagnetism.
PHYSICS 333 Electricity and Magnetism I CLASS DETAILS
Cassak, Paul
in this course are germane to essentially every field in modern physics! · The topics to be covered areFall 2009 PHYSICS 333 Electricity and Magnetism I CLASS DETAILS: · Meeting Times: Tuesday + by appointment + whenever the door is open · Please come by for help with concepts, homework, or other advice
Electric-current Susceptibility and the Chiral Magnetic Effect
Kenji Fukushima; Dmitri E. Kharzeev; Harmen J. Warringa
2009-12-15
We compute the electric-current susceptibility \\chi of hot quark-gluon matter in an external magnetic field B. The difference between the susceptibilities measured in the directions parallel and perpendicular to the magnetic field is ultraviolet finite and given by \\chi^\\parallel-\\chi^\\perp = VTN_c\\sum_f q_f^2 |q_f B|/(2\\pi^2), where V denotes the volume, T the temperature, N_c the number of colors, and q_f the charge of a quark of flavor f. This non-zero susceptibility difference acts as a background to the Chiral Magnetic Effect, i.e. the generation of electric current along the direction of magnetic field in the presence of topological charge. We propose a description of the Chiral Magnetic Effect that takes into account the fluctuations of electric current quantified by the susceptibility. We find that our results are in agreement with recent lattice QCD calculations. Our approach can be used to model the azimuthal dependence of charge correlations observed in heavy ion collisions.
Comments on Critical Electric and Magnetic Fields from Holography
S. Bolognesi; F. Kiefer; E. Rabinovici
2013-01-29
We discuss some aspects of critical electric and magnetic fields in a field theory with holographic dual description. We extend the analysis of arxiv:1109.2920, which finds a critical electric field at which the Schwinger pair production barrier drops to zero, to the case of magnetic fields. We first find that, unlike ordinary weakly coupled theories, the magnetic field is not subject to any perturbative instability originating from the presence of a tachyonic ground state in the W-boson spectrum. This follows from the large value of the 't Hooft coupling \\lambda, which prevents the Zeeman interaction term to overcome the particle mass at high B. Consequently, we study the next possible B-field instability, i.e. monopole pair production, which is the S-dual version of the Schwinger effect. Also in this case a critical magnetic field is expected when the tunneling barrier drops to zero. These Schwinger-type criticalities are the holographic duals, in the bulk, to the fields E or B reaching the tension of F1 or D1 strings respectively. We then discuss how this effect is modified when electric and magnetic fields are present simultaneously and dyonic states in the spectrum can be pair produced by a generic E - B background. Finally, we analyze finite temperature effects on Schwinger criticalities, i.e. in the AdS-Schwarzshild black hole background.
Electric and magnetic field reduction by alternative transmission line options
Stewart, J.R. (Power Technologies, Inc., Schenectady, NY (United States)); Dale, S.J. (Oak Ridge National Lab., TN (United States)); Klein, K.W. (Energetics, Inc., Columbia, MD (United States))
1991-01-01
Ground level electric, and more recently magnetic, fields from overhead power transmission lines are increasingly important considerations in right of way specification, with states setting or planning to set edge of right of way limits. Research has been conducted in high phase order power transmission wherein six of twelve phases are used to transmit power in less physical space and with reduced electrical environmental effects than conventional designs. The first magnetic field testing, as reported in this paper, has verified predictive methods for determination of magnetic fields from high phase order lines. Based on these analytical methods, field profiles have been determined for lines of different phase order of comparable power capacity. Potential advantages of high phase order as a means of field mitigation are discussed. 10 refs., 12 figs., 3 tabs.
ATLAS magnet common cryogenic, vacuum, electrical and control systems
Miele, P; Delruelle, N; Geich-Gimbel, C; Haug, F; Olesen, G; Pengo, R; Sbrissa, E; Tyrvainen, H; ten Kate, H H J
2004-01-01
The superconducting Magnet System for the ATLAS detector at the LHC at CERN comprises a Barrel Toroid, two End Cap Toroids and a Central Solenoid with overall dimensions of 20 m diameter by 26 m length and a stored energy of 1.6 GJ. Common proximity cryogenic and electrical systems for the toroids are implemented. The Cryogenic System provides the cooling power for the 3 toroid magnets considered as a single cold mass (600 tons) and for the CS. The 21 kA toroid and the 8 kA solenoid electrical circuits comprise both a switch-mode power supply, two circuit breakers, water cooled bus bars, He cooled current leads and the diode resistor ramp-down unit. The Vacuum System consists of a group of primary rotary pumps and sets of high vacuum diffusion pumps connected to each individual cryostat. The Magnet Safety System guarantees the magnet protection and human safety through slow and fast dump treatment. The Magnet Control System ensures control, regulation and monitoring of the operation of the magnets. The update...
Chen, Long-Qing
Phase-field simulation of electric-field-induced in-plane magnetic domain switching in magnetic://jap.aip.org/about/rights_and_permissions #12;Phase-field simulation of electric-field-induced in-plane magnetic domain switching in magnetic; published online 22 June 2011) The electric-field-induced in-plane magnetic domain switching in magnetic
Electric-Magnetic Duality and the Heavy Quark Potential
M. Baker
1996-09-05
We use the assumption of electric-magnetic duality to express the heavy quark potential in QCD in terms of a Wilson Loop $W_{eff}(\\Gamma)$ determined by the dynamics of a dual theory which is weakly coupled at long distances. The classical approximation gives the leading contribution to $W_{eff}(\\Gamma)$ and yields a velocity dependent heavy quark potential which for large $R$ becomes linear in $R$, and which for small $R$ approaches lowest order perturbative QCD. The corresponding long distance interaction between color magnetic monopoles is governed by a Yukawa potential. As a consequence the magnetic interaction between the color magnetic moments of the quarks is exponentially damped. The semi-classical corrections to $W_{eff}(\\Gamma)$ due to fluctuations of the classical flux tube should lead to an effective string theory free from the conformal anomaly.
Polinski, J.; Chorowski, M.; Bogdan, P.; Strychalski, M.; Rijk, G. de
2014-01-27
Future accelerators will make extensive use of superconductors made of Nb{sub 3}Sn, which allows higher magnetic fields than NbTi. However, the wind-and-react technology of Nb{sub 3}Sn superconducting magnet production makes polyimide Kapton® non applicable for the coils' electrical insulation. A Nb{sub 3}Sn technology compatible insulation material should be characterized by high radiation resistivity, good thermal conductivity, and excellent mechanical properties. Candidate materials for the electrical insulation of future accelerator's magnet coils have to be radiation certified with respect to potential degradation of their electrical, thermal, and mechanical properties. This contribution presents procedures and results of tests of the electrical and mechanical properties of DGEBA epoxy + D400 hardener, which is one of the candidates for the electrical insulation of future magnets. Two test sample types have been used to determine the material degradation due to irradiation: a untreated one (unirradiated) and irradiated at 77 K with 11 kGy/min intense, 4MeV energy electrons beam to a total dose of 50 MGy.
Response of Holographic QCD to Electric and Magnetic Fields
Oren Bergman; Gilad Lifschytz; Matthew Lippert
2008-06-16
We study the response of the Sakai-Sugimoto holographic model of large N_c QCD at nonzero temperature to external electric and magnetic fields. In the electric case we find a first-order insulator-conductor transition in both the confining and deconfining phases of the model. In the deconfining phase the conductor is described by the parallel 8-brane-anti-8-brane embedding with a current of quarks and anti-quarks. We compute the conductivity and show that it agrees precisely with a computation using the Kubo formula. In the confining phase we propose a new kind of 8-brane embedding, corresponding to a baryonic conductor. In the magnetic field case we show that the critical temperature for chiral-symmetry restoration in the deconfined phase increases with the field and approaches a finite value in the limit of an infinite magnetic field. We also illustrate the nonlinear behavior of the electric and magnetic susceptibilities in the different phases.
Small animal electric and magnetic field exposure systems. Final report
Patterson, R.C.; Dietrich, F.M.
1993-10-01
Laboratory evaluation of electric and magnetic fields (EMF) and cancer in animals requires exposure of relatively large numbers of animals, usually rats or mice, to 60-Hz fields under very well controlled conditions for periods of up to two years. This report describes two exposure systems, the first of which is based on modifications of an existing electric field exposure system to include magnetic field exposure capability. In this system, each module houses 576--768 mice, which can be exposed to electric field levels of up to 100 kV/m and magnetic field levels of up to 10 Gauss. When a module was operated at 10 Gauss, measured levels of noise and vibration fell substantially below the detection threshold for humans. Moreover, temperature rise in the coils did not exceed 12{degrees}C at the 10 Gauss level. Specifications and test results for the second system, which provides magnetic field exposure capability only, are similar, except that each module houses 624--780 mice. After installation of the second system at the West Los Angeles Veterans Medical Center in Los Angeles, California, additional results were obtained. This report provides a complete description of the engineering design, specifications, and test results for the completed systems.
Black Holes in Models with Dilaton Field and Electric or Electric and Magnetic Charges
E. Kyriakopoulos
2006-11-10
Exact static spherically symmetric charged black holes in four dimensions are presented. One of them has only electric charge and another electric and magnetic charges. In these solutions the metric is asymptotically flat, has two horizons, irremovable singularity only at $r=0$, and the dilaton field is singular only at $r=0$. The solution with electric charge only is characterized by three free parameters, the ADM mass, the electric charge and an additional free parameter. It can be considered as a modification of the GHS-GM solution obtained by changing the coupling between dilaton and electromagnetic field. The general dyonic solution is again characterized by three free parameters, the ADM mass, the magnetic charge and an additional free parameter, which is not the electric charge. According to a definition of the no-hair conjecture the solutions are "hairy".A very interesting special case of the dyonic solution is characterized by three free parameters, the ADM mass and the electric and the magnetic charges. The solutions satisfy the dominant as well as the strong energy condition outside and on the external horizon.
Lightning-Driven Electric and Magnetic Fields Measured in the Stratosphere: Implications for Sprites
Thomas, Jeremy N.
Lightning-Driven Electric and Magnetic Fields Measured in the Stratosphere: Implications-Driven Electric and Magnetic Fields Measured in the Stratosphere: Implications for Sprites Jeremy Norman Thomas et al., 2004b], in which the lightning-driven electric and magnetic field changes were rare, while
Resonances Width in Crossed Electric and Magnetic Christian Ferrari a and Hynek Kova r k b
Resonances Width in Crossed Electric and Magnetic Fields Christian Ferrari a and Hynek Kova#20;r#19 con#12;ned to a two- dimensional plane and submitted to homogeneous magnetic and electric #12;elds dimensions in the presence of crossed magnetic and electric #12;elds and a potential type perturbation. We
Chen, Long-Qing
Electric-field-driven magnetization reversal in square-shaped nanomagnet-based multiferroic. Lett. 98, 222509 (2011); 10.1063/1.3597796 Electrically controlled magnetization switching://scitation.aip.org/termsconditions. Downloaded to IP: 128.118.37.128 On: Wed, 27 May 2015 18:58:21 #12;Electric-field-driven magnetization
Eyüboðlu, Murat
MAGNETIC RESONANCE ELECTRICAL IMPEDANCE TOMOGRAPHY (MR-EIT): A new technique for high resolution are measured by using conventional electrical impedance tomography techniques and high resolution magnetic and the point spread function is not space invariant. On the other hand, magnetic field and electrical current
On the computation of the eigenproblems of hydrogen and helium in strong magnetic and electric
On the computation of the eigenproblems of hydrogen and helium in strong magnetic and electric) and helium (two electron problem) in strong magnetic and electric fields. Key Words: Schr¨odinger equation these techniques can not longer be applied in cases where both, a magnetic and an electric field are present
On the computation of the eigenproblems of hydrogen and helium in strong magnetic and electric
On the computation of the eigenproblems of hydrogen and helium in strong magnetic and electric-dimensional Schr¨o- dinger equation for helium (two electron problem) in strong magnetic and electric fields. Key these techniques can no longer be applied in cases where both a magnetic and an electric field are present
Longitudinal study of student conceptual understanding in electricity and magnetism S. J. Pollock
Colorado at Boulder, University of
Longitudinal study of student conceptual understanding in electricity and magnetism S. J. Pollock at the freshman level on juniors' performance on a conceptual survey of Electricity and Magnetism E&M . We measured student performance on a research-based conceptual instrument--the Brief Electricity & Magnetism
But Does It Last? Sustaining a Research-Based Curriculum in Upper-Division Electricity & Magnetism
Colorado at Boulder, University of
But Does It Last? Sustaining a Research-Based Curriculum in Upper-Division Electricity & Magnetism course approach in junior-level electricity and magnetism (E&M). Almost all developed materials (i, electricity and magnetism, assessment PACS: 01.30.Ib, 01.40.Di, 01.40.Fk, 01.40.G-, 01.40.gb INTRODUCTION
EE 301 Electricity, Magnetism, and Fields Dr. David M. Klymyshyn, Ph.D., P.Eng.
Saskatchewan, University of
EE 301 Electricity, Magnetism, and Fields Dr. David M. Klymyshyn, Ph.D., P.Eng. Office: 3B06 966-5393 david.klymyshyn@usask.ca Calendar Description: Covers the fundamental laws governing electric and magnetic fields and some applications. Topics include static electric fields, Gauss's law, static magnetic
Learning physics in context: a study of student learning about electricity and magnetism
Colorado at Boulder, University of
Learning physics in context: a study of student learning about electricity and magnetism This paper a novel university class in electricity and magnetism are analyzed to demonstrate the central in electricity and magnetism. Many of these students, who had passed the introductory courses with high grades
Massive photons and Dirac monopoles: electric condensate and magnetic confinement
M. S. Guimaraes; R. Rougemont; C. Wotzasek; C. A. D. Zarro
2013-05-13
We use the generalized Julia-Toulouse approach (GJTA) for condensation of topological currents (charges or defects) to argue that massive photons can coexist consistently with Dirac monopoles. The Proca theory is obtained here via GJTA as a low energy effective theory describing an electric condensate and the mass of the vector boson is responsible for generating a Meissner effect which confines the magnetic defects in monopole-antimonopole pairs connected by physical open magnetic vortices described by Dirac brane invariants, instead of Dirac strings.
Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1
Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1 magnetism electrically. The gap opened by doped magnetic ions can lead to a short-range Bloembergen 2010; published 28 February 2011) We study theoretically the RKKY interaction between magnetic
The electric and magnetic form factors of the proton
A1 Collaboration; J. C. Bernauer; M. O. Distler; J. Friedrich; Th. Walcher; P. Achenbach C. Ayerbe Gayoso; R. Böhm; L. Debenjak; L. Doria; A. Esser; H. Fonvieille; M. Gómez Rodrígues de la Paz; J. M. Friedrich; M. Makek; H. Merkel; D. G. Middleton; U. Müller; L. Nungesser; J. Pochodzalla; M. Potokar; S. Sánchez Majos; B. S. Schlimme; S. Širca; M. Weinriefer
2014-07-29
The paper describes a precise measurement of electron scattering off the proton at momentum transfers of $0.003 \\lesssim Q^2 \\lesssim 1$\\ GeV$^2$. The average point-to-point error of the cross sections in this experiment is $\\sim$ 0.37%. These data are used for a coherent new analysis together with all world data of unpolarized and polarized electron scattering from the very smallest to the highest momentum transfers so far measured. The extracted electric and magnetic form factors provide new insight into their exact shape, deviating from the classical dipole form, and of structure on top of this gross shape. The data reaching very low $Q^2$ values are used for a new determination of the electric and magnetic radii. An empirical determination of the Two-Photon-Exchange (TPE) correction is presented. The implications of this correction on the radii and the question of a directly visible signal of the pion cloud are addressed.
Polarizable vacuum analysis of electric and magnetic fields
Xing-Hao Ye
2009-08-22
The electric and magnetic fields are investigated on the basis of quantum vacuum. The analysis of the electromagnetic energy and force indicates that an electric field is a polarized distribution of the vacuum virtual dipoles, and that a magnetic field in vacuum is a rearrangement of the vacuum polarization. It means that an electromagnetic wave is a successional changing of the vacuum polarization in space. Also, it is found that the average half length of the virtual dipoles around an elementary charge is a=2.8 *10^(-15)m. The result leads to the step distribution of the field energy around an electron, the relation between the fine structure constant and the vacuum polarization distribution, and an extremely high energy density of the electromagnetic field.
Magnetic and electric screening masses from Polyakov-loop correlations
Y. Maezawa; S. Aoki; S. Ejiri; T. Hatsuda; N. Ishii; K. Kanaya; N. Ukita; T. Umeda
2008-11-04
Screening properties of the quark gluon plasma are studied from Polyakov-loop correlation in lattice QCD simulations with two flavors of improved Wilson quarks at temperatures $T/\\Tpc \\simeq 1$--4 where $\\Tpc$ is the pseudocritical temperature. Using the Euclidean-time reflection symmetry and the charge conjugation symmetry, we introduce various types of Polyakov-loop correlation functions and extract screening masses in magnetic and electric sectors. We find that the temperature dependence of the screening masses are well described by the weak coupling expansion. We also find that a ratio of the screening masses in the electric sector to the magnetic sector shows qualitative agreement with a prediction from the dimensionally-reduced effective field theory and the N=4 supersymmetric Yang-Mills theory at $1.3 < T/\\Tpc < 3$.
Dymnikova, Irina
2015-01-01
In nonlinear electrodynamics coupled to gravity, regular spherically symmetric electrically charged solutions satisfy the weak energy condition and have obligatory de Sitter centre. By the G\\"urses-G\\"ursey algorithm they are transformed to spinning electrically charged solutions asymptotically Kerr-Newman for a distant observer. Rotation transforms de Sitter center into de Sitter vacuum surface which contains equatorial disk $r=0$ as a bridge. We present general analysis of the horizons, ergoregions and de Sitter surfaces, as well as the conditions of the existence of regular solutions to the field equations. We find asymptotic solutions and show that de Sitter vacuum surfaces have properties of a perfect conductor and ideal diamagnetic, violation of the weak energy condition is prevented by the basic requirement of electrodynamics of continued media, and the Kerr ring singularity is replaced with the superconducting current.
Spontaneous Symmetry Breaking in Presence of Electric and Magnetic Charges
Pushpa; P. S. Bisht; O. P. S. Negi
2010-11-17
Starting with the definition of quaternion gauge theory, we have undertaken the study of SU(2)_{e}\\times SU(2)_{m}\\times U(1)_{e}\\times U(1)_{m} in terms of the simultaneous existence of electric and magnetic charges along with their Yang - Mills counterparts. As such, we have developed the gauge theory in terms of four coupling constants associated with four - gauge symmetry SU(2)_{e}\\times SU(2)_{m}\\times U(1)_{e}\\times U(1)_{m}. Accordingly, we have made an attempt to obtain the abelian and non - Abelian gauge structures for the particles carrying simultaneously the electric and magnetic charges (namely dyons). Starting from the Lagrangian density of two SU(2)\\times U(1) gauge theories responsible for the existence of electric and magnetic charges, we have discussed the consistent theory of spontaneous symmetry breaking and Higgs mechanism in order to generate the masses. From the symmetry breaking, we have generated the two electromagnetic fields, the two massive vector W^{\\pm} and Z^{0} bosons fields and the Higgs scalar fields.
Electrically driven nuclear spin resonance in a single-molecule magnet
Vallette, Bruno
Electrically driven nuclear spin resonance in a single-molecule magnet Institut NÃ©el : Nanospin Institut NÃ©el, CNRS-UJF, Grenoble NanoSpin #12;Â· Molecular magnets are characterised by : a magnetic moment a strong uniaxial anisotropy Mn12 Molecular magnets Fe8 #12;Â· Molecular magnets are characterised
Valfells, Ágúst
Effects of an external magnetic field, and of oblique radio-frequency electric fields magnetic field, the rf magnetic field, and of an oblique rf electric field, on multipactor discharge that a magnetic field parallel to either the rf electric field or the dc electric field does not qualitatively
In-plane electric fields in magnetic islands during collisionless magnetic reconnection
Chen Lijen; Bhattacharjee, Amitava; Torbert, Roy B.; Bessho, Naoki; Daughton, William; Roytershteyn, Vadim
2012-11-15
Magnetic islands are a common feature in both the onset and nonlinear evolution of magnetic reconnection. In collisionless regimes, the onset typically occurs within ion-scale current layers leading to the formation of magnetic islands when multiple X lines are involved. The nonlinear evolution of reconnection often gives rise to extended electron current layers (ECL) which are also unstable to formation of magnetic islands. Here, we show that the excess negative charge and strong out-of-plane electron velocity in the ECL are passed on to the islands generated therein, and that the corresponding observable distinguishing the islands generated in the ECL is the strongly enhanced in-plane electric fields near the island core. The islands formed in ion-scale current layers do not have these properties of the ECL-generated islands. The above result provides a way to assess the occurrence and importance of extended ECLs that are unstable to island formation in space and laboratory plasmas.
ELECTRIC TURBULENCE IN A PLASMA SUBJECT TO A STRONG MAGNETIC FIELD
Vasseur, Alexis
ELECTRIC TURBULENCE IN A PLASMA SUBJECT TO A STRONG MAGNETIC FIELD G. Loeper12 A. Vasseur12 of a stochastic electric field on a plasma subject to a strong magnetic field. This is motivated by the study Abstract We consider in this paper a plasma subject to a strong deterministic magnetic field and we
EE 202.3 (3L-3P alt weeks) Electric and Magnetic Fields and Circuits
Saskatchewan, University of
for magnetic circuits, principles of linear motors and generators The course is about 1/3 fields and 2EE 202.3 (3L-3P alt weeks) Electric and Magnetic Fields and Circuits Department of Electrical and Computer Engineering Fall 2015 Description: Further develops the theory and analysis of electric
6/2015 E&M forces-1/8 ELECTRIC AND MAGNETIC FORCES
Gustafsson, Torgny
6/2015 E&M forces-1/8 ELECTRIC AND MAGNETIC FORCES PURPOSE: To study the deflection of a beam of electrons by electric and magnetic fields. APPARATUS: Electron beam tube, stand with coils, power supply the electrons strike a fluorescent screen. As the electrons move in the horizontal (x) direction, an electric
Cognitive Issues in Upper-Division Electricity & Magnetism Steven J. Pollock
Colorado at Boulder, University of
Cognitive Issues in Upper-Division Electricity & Magnetism Steven J. Pollock and Stephanie V Electricity & Magnetism I (Electro- and Magneto-Statics). As part of our efforts to systematically improve interventions at the upper division. Keywords: physics education research, course reform, electricity
Electron dynamics in parallel electric and magnetic fields
Christian Bracher; Tobias Kramer; John B. Delos
2005-10-13
We examine the spatial distribution of electrons generated by a fixed energy point source in uniform, parallel electric and magnetic fields. This problem is simple enough to permit analytic quantum and semiclassical solution, and it harbors a rich set of features which find their interpretation in the unusual and interesting properties of the classical motion of the electrons: For instance, the number of interfering trajectories can be adjusted in this system, and the turning surfaces of classical motion contain a complex array of singularities. We perform a comprehensive analysis of both the semiclassical approximation and the quantum solution, and we make predictions that should serve as a guide for future photodetachment experiments.
Paperno, Eugene
-noise flux-fluctuations to a magnetic entity similar to the dc current in the electric case. The present work that relates the time-derivative of the magnetic flux to the electric current. The magnetic noise measurements to a magnetic entity similar to the dc current in the electric case. The present work shows both theoretically
Full Action for an Electromagnetic Field with Electrical and Magnetic Charges
S. S. Serova; S. A. Serov
2010-09-25
The paper offers the full action for an electromagnetic field with electrical and magnetic charges; Feynman laws are formulated for the calculation of the interaction cross-sections for electrically and magnetically charged particles on the base of offered action within relativistic quantum field theory. Derived with formulated Feynman rules cross-section of the interaction between an elementary particle with magnetic charge and an elementary particle with electrical charge proves to be equal zero.
A model of the ULF magnetic and electric field generated from a dust devil
Cummer, Steven A.
A model of the ULF magnetic and electric field generated from a dust devil W. M. Farrell,1 J. R emit ULF magnetic radiation. On Mars, dust devils may also generate such magnetic emissions, which in the vortex wind fields accounts for the magnetic emission. To test this hypothesis in general
Blakely, Richard J.; Sherrod, Brian; Weaver, Craig; Wells, Ray E.; Rohay, Alan C.
2014-06-11
Magnetic and gravity data, collected in south-central Washington near the Yakima Fold and Thrust Belt (YFTB) are used to model upper crustal structure, the extent of the late Columbia River Basalt flow named the Ice Harbor member, the vertical conduits (dikes) that the Ice Harbor erupted from, and whether the dikes are offset or affected by faulting on the Wallula Fault zone.
Zakirjon Kanokov; Juern W. P. Schmelzer; Avazbek K. Nasirov
2009-04-07
An analysis of a variety of existing experimental data leads to the conclusion on the existence of a resonance mechanism allowing weak magnetic fields to affect biological processes. These fields may either be static magnetic fields comparable in magnitude with the magnetic field of the earth or weak ultra-low frequency time-dependent fields. So far, a generally accepted theoretical model allowing one to understand the effect of magnetic and electric fields on biological processes is not available. By this reason, it is not clear which characteristics of the fields, like magnetic and electric field strength, frequency of change of the field, shape of the electromagnetic wave, the duration of the magnetic or electric influence or some particular combination of them, are responsible for the biological effect. In the present analysis it is shown that external time-independent magnetic fields may cause a resonance amplification of ionic electric currents in biological tissues and, in particular, in the vasculature system due to a Brownian motion of charges. These resonance electric currents may cause necrotic changes in the tissues or blood circulation and in this way significantly affect the biological organism. The magnitude of the magnetic fields leading to resonance effects is estimated, it is shown that it depends significantly on the radius of the blood capillaries.
Dunin-Borkowski, Rafal E.
Electron Holography of Magnetic and Electric Fields in Nanostructured Materials Prepared for TEM local angle and spacing carry the desired information about magnetic and electric fields. Electron not be perturbed by stray (fringing) magnetic or electric fields. When examining magnetic nanostructures in cross
Electric and magnetic screenings of gluons in a model with dimension-2 gluon condensate
Fukun Xu; Mei Huang
2011-11-22
Electric and magnetic screenings of the thermal gluons are studied by using the background expansion method in a gluodynamic model with dimension-2 gluon condensate. At low temperature, the electric and magnetic gluons are degenerate. With the increasing of temperature, it is found that the electric and magnetic gluons start to split at certain temperature $T_0$. The electric screening mass changes rapidly with temperature when $T>T_0$, and the Polyakov loop expectation value rises sharply around $T_0$ from zero in the vacuum to a value around 0.8 at high temperature. This suggests that the color electric deconfinement phase transition is driven by electric gluons. It is also observed that the magnetic screening mass keeps almost the same as its vacuum value, which manifests that the magnetic gluons remains confined. Both the screening masses and the Polyakov loop results are qualitatively in agreement with the Lattice calculations.
Spin filtering in a ?-doped magnetic-electric-barrier nanostructure
Li, Shuai; Lu, Mao-Wang Jiang, Ya-Qing; Chen, Sai-Yan
2014-09-15
We report a theoretical study on spin-polarized transport in a ?-doped magnetic-electric-barrier nanostructure, which can be realized in experiments by depositing two ferromagnetic stripes on top and bottom of a semiconductor heterostructure under an applied voltage and by using atomic layer doping technique. The spin-polarized behavior of the electron in this device is found to be quite sensitive to the ?-doping. One can conveniently tune the degree of the electron spin polarization by adjusting the weight and/or position of the ?-doping. Thus, the involved nansosystem can be employed as a controllable spin filter, which may be helpful for exploiting new spin-polarized source for spintronics applications.
Quantization of Dyon Charge and Electric-Magnetic Duality in String Theory
Ashoke Sen
1992-09-05
We analyze the allowed spectrum of electric and magnetic charges carried by dyons in (toroidally compactified) heterotic string theory in four dimensions at arbitrary values of the string coupling constant and $\\theta$ angle. The spectrum is shown to be invariant under electric-magnetic duality transformation, thereby providing support to the conjecture that this is an exact symmetry in string theory.
The Theory of Electric and Magnetic Susceptibilities: Unfinished Second Edition TEXTUAL BACKGROUND
Saffman, Mark
1 The Theory of Electric and Magnetic Susceptibilities: Unfinished Second Edition TEXTUAL BACKGROUND John Van Vleck published his classic monograph "The Theory of Electric and Magnetic, "Susceptibilities in the Old Quantum Theory, Contrasted with the New" in the original edition was to have been
Far-field mapping of the longitudinal magnetic and electric optical fields C. Ecoffey, T. Grosjean
Boyer, Edmond
) become noticeable and light has to be seen as a 3D vectorial electromagnetic field. The enhancedFar-field mapping of the longitudinal magnetic and electric optical fields C. Ecoffey, T. Grosjean of the longitudinal magnetic and electric optical fields with a standard scanning microscope that involves a high
Irradiation requirements of Nb3Sn based SC magnets electrical insulation
McDonald, Kirk
Irradiation requirements of Nb3Sn based SC magnets electrical insulation developed within the Eu and Power Engineering #12;Outline · Motivation of launching EuCARD irradiation task · Nb3Sn SC magnet coils electrical insulation candidates · EuCARD insulators certification conditions · Post irradiation tests
Two-potential theory of electric and magnetic charges via duality transformation
Chandrasekhar Chatterjee; Indrajit Mitra; H. S. Sharatchandra
2012-03-06
Dirac, Schwinger and Zwanziger theories of electric and magnetic charges are obtained via duality transformation. Analogous construction for three Euclidean dimensions, with magnetic charges interacting with electric currents, is also done. The role of Dirac strings as dislocations in the configurations of gauge potential is emphasized.
Electric Charge in Interaction with Magnetically Charged Black Holes
J. H. Kim; Sei-Hoon Moon
2007-10-02
We examine the angular momentum of an electric charge e placed at rest outside a dilaton black hole with magnetic charge Q. The electromagnetic angular momentum which is stored in the electromagnetic field outside the black hole shows several common features regardless of the dilaton coupling strength, though the dilaton black holes are drastically different in their spacetime structure depending on it. First, the electromagnetic angular momentum depends on the separation distance between the two objects and changes monotonically from eQ to 0 as the charge goes down from infinity to the horizon, if rotational effects of the black hole are discarded. Next, as the black hole approaches extremality, however, the electromagnetic angular momentum tends to be independent of the distance between the two objects. It is then precisely $eQ$ as in the electric charge and monopole system in flat spacetime. We discuss why these effects are exhibited and argue that the above features are to hold in widely generic settings including black hole solutions in theories with more complicated field contents, by addressing the no hair theorem for black holes and the phenomenon of field expulsion exhibited by extremal black holes.
Mansuripur, Masud
2015-01-01
The classical theory of electrodynamics cannot explain the existence and structure of electric and magnetic dipoles, yet it incorporates such dipoles into its fundamental equations, simply by postulating their existence and properties, just as it postulates the existence and properties of electric charges and currents. Maxwell's macroscopic equations are mathematically exact and self-consistent differential equations that relate the electromagnetic (EM) field to its sources, namely, electric charge-density $\\rho_{free}$, electric current-density $J_{free}$, polarization P, and magnetization M. At the level of Maxwell's macroscopic equations, there is no need for models of electric and magnetic dipoles. For example, whether a magnetic dipole is an Amperian current-loop or a Gilbertian pair of north and south magnetic monopoles has no effect on the solution of Maxwell's equations. Electromagnetic fields carry energy as well as linear and angular momenta, which they can exchange with material media - the seat of...
Measurements of electric and magnetic fields in the Waianae, Hawaii area
Mantiply, E.D.
1992-07-01
During November 27--30, 1990, the US Environmental Protection Agency (EPA) conducted a measurement survey of electric and magnetic field levels along the southwest coast of Oahu, Hawaii. These measurements were requested by the State of Hawaii to determine the levels of radiofrequency (RF) electric and magnetic fields near Naval radio transmitters at Lualualei. The objective was to determine maximum fields in residential areas. This report documents the measurement results. Also, a few measurements were made of extremely-low-frequency (ELF) electric and magnetic fields at 60 hertz, the frequency used for electrical power.
Fast vacuum decay into particle pairs in strong electric and magnetic fields
Yoshimasa Hidaka; Takumi Iritani; Hideo Suganuma
2011-02-01
We discuss fermion pair productions in strong electric and magnetic fields. We point out that, in the case of massless fermions, the vacuum persistency probability per unit time and volume is zero in the strong electric and magnetic fields, while it is finite when the magnetic field is absent. The contribution from the lowest Landau level (LLL) dominates this phenomenon. We also discuss dynamics of the vacuum decay, using an effective theory of the LLL projection, taking into account the back reaction.
Halgamuge, Malka N.
of a static magnetic field is required, and biological effects can be expected for frequencies below a few for exposures to low-frequency magnetic fields in the mili-Tesla range. No resonance frequencies or amplitude Lines; Interaction Models; Biological Effects Introduction Static magnetic and electric fields occur
Magnetized Target Fusion: Input to the 35-yr Fusion Long-Range Electric Plan
Magnetized Target Fusion: Input to the 35-yr Fusion Long-Range Electric Plan G. A. Wurden Fusion to the 35-yr Fusion Long-Range Electric Plan Â· Imagine a fusion concept where: Â· The plasma beta ranges from to the 35-yr Fusion Long-Range Electric Plan Â· MTF offers a uniquely different pathway to achieving
Calculation of the Electric and Magnetic Root Mean Squared Radiuses of Proton Based on MIT Bag Model
Maryam Momeni Feili; Mahvash Zandi
2015-01-12
The electric and magnetic bag radiuses of the proton can be determined by MIT bag model based on electric and magnetic form factors of the proton. Also we determined electric and magnetic root mean squared radiuses of the proton, using of bag radius and compared with other results suggests a suitable compatibility.
Chen, Long-Qing
2011-01-01
PHYSICAL REVIEW B 83, 134408 (2011) Size-dependent electric voltage controlled magnetic anisotropy) We present a phenomenological scheme to study the size-dependent electric voltage-controlled magnetic between the magnetic and electric polarizations.13 Of particular interest in the multiferroic
Jones, Alan G.
J. Geomag. Geoelectr., 49, 767-789, 1997 Electric and Magnetic Field Galvanic Distortion importance for many of the BC87 sites. However, even a combined electric and magnetic field galvanic-inductive (usually called galvanic) distortion of the electric andjor magnetic fields. Relevant studies include
Proton radiography of dynamic electric and magnetic fields in laser-produced high-energy measurements of the electric E and magnetic B fields produced in laser-foil interactions and during, and dissipation of self-generated electric E and magnetic B fields by inter- actions of laser light with matter1
Chandrasekar, Rohith; Lagutchev, Alexei; Shalaev, Vladimir M; Ciraci, Cristian; Smith, David R; Kildishev, Alexander V
2015-01-01
Plasmonic resonances in metallic nanostructures have been shown to drastically enhance local electromagnetic fields, and thereby increase the efficiency of nonlinear optical phenomena, such as second harmonic generation (SHG). While it has been experimentally observed that enhanced fields can significantly boost SHG, to date it proved difficult to probe electrical and magnetic resonances in one and the same nanostructure. This however is necessary to directly compare relative contributions of electrical and magnetic components of SHG enhancement. In this paper we report an experimental study of a metasurface capable of providing electrical and magnetic resonant SHG enhancement for TM polarization. Our metasurface could be engineered such that the peak frequencies of electrical and magnetic resonances could be adjusted independently. We used this feature to distinguish their relative contributions. Experimentally it was observed that the magnetic resonance provides only 50% as much enhancement to SHG as compar...
Electric-Magnetic Duality and Effective Field Theories
Cesar Gomez; Rafael Hernandez
1995-10-05
Lectures given by C.G. in the Advanced School on Effective Theories (Almu\\~{n}ecar, Granada, 1995) on duality in N=2 supersymmetric Yang-Mills, and the coupling to gravity.
Porsev, S G; Flambaum, V V
2010-01-01
We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.
S. G. Porsev; J. S. M. Ginges; V. V. Flambaum
2011-03-02
We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.
Stoffel, J.B.; Pentecost, E.D.; Roman, R.D.; Traczyk, P.A.
1994-11-01
This report provides background information about (1) the electric and magnetic fields (EMFs) of high-voltage transmission lines at typical voltages and line configurations and (2) typical transmission line costs to assist on alternatives in environmental documents. EMF strengths at 0 {+-} 200 ft from centerline were calculated for ac overhead lines, and for 345 and 230-kV ac underground line and for a {+-}450-kV dc overhead line. Compacting and height sensitivity factors were computed for the variation in EMFs when line conductors are moved closer or raised. Estimated costs for the lines are presented and discussed so that the impact of using alternative strategies for reducing EMF strengths and the implications of implementing the strategies can be better appreciated.
Electrical conductivity of quark matter in magnetic field
B. Kerbikov; M. Andreichikov
2011-12-05
Fermion currents in dense quark matter embedded into magnetic field are under intense discussions motivated by Chiral Magnetic Effect. We argue that conductivity of quark matter may be independent of the magnetic field direction and not proportional to the magnetic field strength.
Eyüboðlu, Murat
- electrical impedance tomography, magnetic resonance imaging. I. INTRODUCTION Electrical impedance tomography conductivity images [11]. Both of these techniques can be named as magnetic resonance-electrical impedanceAbstract- A novel imaging method for electrical impedance tomography is implemented. In this method
Sotani, Hajime
2015-01-01
We systematically examine the properties of null geodesics around an electrically charged, asymptotically flat black hole in Eddington-inspired Born-Infeld gravity, varying the electric charge of black hole and the coupling constant in the theory. We find that the radius of the unstable circular orbit for massless particle decreases with the coupling constant, if the value of the electrical charge is fixed. Additionally, we consider the strong gravitational lensing around such a black hole. We show that the deflection angle, the position angle of the relativistic images, and the magnification due to the light bending in strong gravitational field are quite sensitive to the parameters determining the black hole solution. Thus, through the accurate observations associated with the strong gravitational lensing, it might be possible to reveal the gravitational theory in a strong field regime.
Holographic description of the Schwinger effect in electric and magnetic fields
Yoshiki Sato; Kentaroh Yoshida
2015-04-20
We consider a generalization of the holographic Schwinger effect proposed by Semenoff and Zarembo to the case with constant electric and magnetic fields. There are two ways to turn on magnetic fields, i) the probe D3-brane picture and ii) the string world-sheet picture. In the former picture, magnetic fields both perpendicular and parallel to the electric field are activated by a Lorentz transformation and a spatial rotation. In the latter one, the classical solutions of the string world-sheet corresponding to circular Wilson loops are generalized to contain two additional parameters encoding the presence of magnetic fields.
Bernhard Rothenstein; Stefan Popescu; George J. Spix
2006-01-05
We propose a simple relativistic derivation of the electric and the magnetic fields generated by an electric point charge moving with constant velocity. Our approach is based on the radar detection of the point space coordinates where the fields are measured. The same equations were previously derived in a relatively complicated way2 based exclusively on general electromagnetic field equations and without making use of retarded potentials or relativistic equations
Effective tight-binding model for MX2 under electric and magnetic fields
Kavungal Veedu, Shanavas [ORNL; Satpathy, S [University of Missouri, Columbia
2015-01-01
We present a systematic method for developing a five band Hamiltonian for the metal d orbitals that can be used to study the effect of electric and magnetic fields on multilayer MX2 (M=Mo,W and X=S,Se) systems. On a hexagonal lattice of d orbitals, the broken inversion symmetry of the monolayers is incorporated via fictitious s orbitals at the chalcogenide sites. A tight-binding Hamiltonian is constructed and then downfolded to get effective d orbital overlap parameters using quasidegenerate perturbation theory. The steps to incorporate the effects of multiple layers, external electric and magnetic fields are also detailed. We find that an electric field produces a linear-k Rashba splitting around the point, while a magnetic field removes the valley pseudospin degeneracy at the K points. Our model provides a simple tool to understand the recent experiments on electric and magnetic control of valley pseudospin in monolayer dichalcogendies.
Mamishev, Alexander V
1994-01-01
An accurate determination and characterization of electric and magnetic fields produced by power lines is a complex task. Different models must be used for far fields and for near fields. This study is centered on computation and measurement aspects...
A two-phase spherical electric machine for generating rotating uniform magnetic fields
Lawler, Clinton T. (Clinton Thomas)
2007-01-01
This thesis describes the design and construction of a novel two-phase spherical electric machine that generates rotating uniform magnetic fields, known as a fluxball machine. Alternative methods for producing uniform ...
New bounds on neutrino electric millicharge from GEMMA experiment on neutrino magnetic moment
Victor B. Brudanin; Dmitry V. Medvedev; Alexander S. Starostin; Alexander I. Studenikin
2014-11-09
Using the new limit on the neutrino anomalous magnetic moment recently obtained by GEMMA experiment we get an order-of-magnitude estimation for possible new direct upper bound on the neutrino electric millicharge $\\mid q_{\
Axion electrodynamics and dark matter fingerprints in the terrestrial magnetic and electric fields
A. B. Balakin; L. V. Grunskaya
2012-09-27
We consider mathematical aspects of the axion electrodynamics in application to the problem of evolution of geomagnetic and terrestrial electric fields, which are coupled by relic axions born in the early Universe and (hypothetically) forming now the cold dark matter. We find axionic analogs of the Debye potentials, well-known in the standard Faraday - Maxwell electrodynamics, and discuss exact solutions to the equations of the axion electrodynamics describing the state of axionically coupled electric and magnetic fields in a spherical resonator Earth-Ionosphere. We focus on the properties of the specific electric and magnetic oscillations, which appeared as a result of the axion-photon coupling in the dark matter environment. We indicate such electric and magnetic field configurations as longitudinal electro-magnetic clusters.
Anomalous delta-type electric and magnetic two-nucleon interactions
Nicolae Bogdan Mandache
2009-04-07
Anomalous delta-type interactions, of both electric and magnetic nature, are introduced between the overlapping peripheral structures of the nucleons, which may explain the spin-triplet deuteron state and the absence of other nucleon-nucleon bound states.
3.15 Electrical, Optical & Magnetic Materials and Devices, Fall 2003
Ross, Caroline A.
Explores the relationships which exist between the performance of electrical, optical, and magnetic devices and the microstructural characteristics of the materials from which they are constructed. Features a device-motivated ...
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
Nouri, N; Brown, M A; Carr, R; Filippone, B; Osthelder, C; Plaster, B; Slutsky, S; Swank, C
2015-01-01
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
N. Nouri; A. Biswas; M. A. Brown; R. Carr; B. Filippone; C. Osthelder; B. Plaster; S. Slutsky; C. Swank
2015-11-10
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
N. Nouri; A. Biswas; M. A. Brown; R. Carr; B. Filippone; C. Osthelder; B. Plaster; S. Slutsky; C. Swank
2015-08-17
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
Rouhani, S.Z.
1996-12-03
In most electrochemical batteries which generate electricity through the reaction of a battery electrode with an electrolyte solution, the chemical composition, and thus the weight and density, of the electrode changes as the battery discharges. The invention measures a parameter of the battery which changes as the weight of the electrode changes as the battery discharges and relates that parameter to the value of the parameter when the battery is fully charged and when the battery is functionally discharged to determine the state-of-charge of the battery at the time the parameter is measured. In one embodiment, the weight of a battery electrode or electrode unit is measured to determine the state-of-charge. In other embodiments, where a battery electrode is located away from the geometrical center of the battery, the position of the center of gravity of the battery or shift in the position of the center of gravity of the battery is measured (the position of the center of gravity changes with the change in weight of the electrode) and indicates the state-of-charge of the battery. 35 figs.
Rouhani, S. Zia (Idaho Falls, ID)
1996-01-01
In most electrochemical batteries which generate electricity through the reaction of a battery electrode with an electrolyte solution, the chemical composition, and thus the weight and density, of the electrode changes as the battery discharges. The invention measures a parameter of the battery which changes as the weight of the electrode changes as the battery discharges and relates that parameter to the value of the parameter when the battery is fully charged and when the battery is functionally discharged to determine the state-of-charge of the battery at the time the parameter is measured. In one embodiment, the weight of a battery electrode or electrode unit is measured to determine the state-of-charge. In other embodiments, where a battery electrode is located away from the geometrical center of the battery, the position of the center of gravity of the battery or shift in the position of the center of gravity of the battery is measured (the position of the center of gravity changes with the change in weight of the electrode) and indicates the state-of-charge of the battery.
Observations on student difficulties with mathematics in upper-division electricity and magnetism
Colorado at Boulder, University of
Observations on student difficulties with mathematics in upper-division electricity and magnetism Initiative and Department of Physics, University of Colorado, Boulder, Colorado 80309, USA (Received 28 July 2011; published 27 March 2012) We discuss common difficulties in upper-division electricity
Garmestani, Hamid
Enhancement of thermal and electrical properties of carbon nanotube polymer composites by magnetic and electrical properties of single wall carbon nanotube CNT -polymer composites are significantly enhanced. INTRODUCTION The addition of small quantities of carbon nanotubes CNTs to polymer composites is known to cause
M. M. Stetsko
2013-06-10
Thermal radiation of electrically charged fermions from rotating black hole with electric and magnetic charges in de Sitter space is considered. The tunnelling probabilities for outgoing and incoming particles are obtained and the Hawking temperature is calculated. The relation for the classical action for the particles in the black hole's background is also found.
Version 2.0 Finite nuclear mass corrections to electric and magnetic
Pachucki, Krzysztof
for the leading corrections to the relativistic contribution to energy, the transition electric dipole moment to rovibrational energies in diatomic molecules. 2 #12; Further examples are finite nuclear mass correctionsVersion 2.0 Finite nuclear mass corrections to electric and magnetic interactions in diatomic
Electric Field Control of Ferromagnetism and Magnetic Devices Using Multiferroics
Heron, John Thomas
2013-01-01
magnetoelectrics and spintronic devices. The two conceptsof a magnetization and spintronic devices. The field ofof multiferroics in spintronic devices has been either to
K. Azizi
2009-02-16
Due to the very short life time of the $\\Delta$ baryons, a direct measurement on the electromagnetic moments of these systems is almost impossible in the experiment and can only be done indirectly. Although only for the magnetic dipole moments of $\\Delta^{++}$ and $\\Delta^{+}$ systems there are some experimental data, the theoretical, phenomenological and lattice calculations could play crucial role. In present work, the magnetic dipole ($\\mu_{\\Delta}$) , electric quadrupole ($Q_{\\Delta}$) and magnetic octupole ($O_{\\Delta}$) moments of these baryons are computed within the light cone QCD sum rules. The results are compared with the predictions of the other phenomenological approaches, lattice QCD and existing experimental data.
Martin, D A
2015-01-01
We study evolution equations and stationary homogeneous solutions for electric and magnetic field amplitudes in a ring cavity with flat mirrors. The cavity is filled with a positive or negative refraction index material with third order Kerr-like electric nonlinearities and also magnetic nonlinearities, which can be relevant in metamaterials. We consider the degree of freedom of polarization in the incident beam. It is found that considering a magnetic nonlinearity increases the variety of possible qualitatively different solutions. A classification of solutions is proposed in terms of the number of bifurcations. The analysis can be useful for the implementation of optical switching or memory storage using ring cavities with non linear materials.
The United Theory of the Two Fields of the Electric and Magnetic Nature
Rasulkhozha S. Sharafiddinov
2010-12-07
Each of electrically charged particles testifies in favor of the existence of a kind of the magnetically charged monoparticle. As a consequence, only the corresponding mononeutrinos answer for quantization of the electric charges of all neutrinos. Therefore, to understand the nature of matter at the fundamental level, one must use the electromagnetic field as the field of the unified system of the photon and monophoton where the electric and magnetic forces of the nature are united. Some logical and laboratory confirmations of the availability of compound structure of gauge invariance have been listed which say also about the connection between the states of elementary particles and monoparticles.
Electric Field Control of Ferromagnetism and Magnetic Devices Using Multiferroics
Heron, John Thomas
2013-01-01
Agnes Barthelemy. Oxide spintronics. IEEE TRANSAC- TIONS ONM. Bibes, and A. Barthelemy. Spintronics with multiferroics.136] Evgeny Y. Tsymbal. Spintronics: Electric toggling of
Kanai, S.; Nakatani, Y.; Yamanouchi, M.; Ikeda, S.; Sato, H.; Matsukura, F.; Ohno, H.
2014-05-26
We propose and demonstrate a scheme for magnetization switching in magnetic tunnel junctions, in which two successive voltage pulses are applied to utilize both spin-transfer torque and electric field effect. Under this switching scheme, a CoFeB/MgO magnetic tunnel junction with perpendicular magnetic easy axis is shown to switch faster than by spin-transfer torque alone and more reliably than that by electric fields alone.
Tadesse, Tilaye; Alexei, Pevtsov A; Macneice, P; Gosain, S
2013-01-01
Solar eruptive phenomena, like flares and coronal mass ejections(CMEs) are governed by magnetic fields. To describe the structure of these phenomena one needs information on the magnetic flux density and the electric current density vector components in three dimensions throughout the atmosphere. However, current spectro-polarimetric measurements typically limit the determination of the vector magnetic field only to the photosphere. Therefore, there is considerable interest in accurate modeling of the solar coronal magnetic field using photospheric vector magnetograms as boundary data. In this work, we model the coronal magnetic field for global solar atmosphere using a nonlinear force-free field(NLFFF) extrapolation codes implemented to a synoptic maps of photospheric vector magnetic field synthesized from Vector Spectromagnetograph (VSM) on Synoptic Optical Long-term Investigations of the Sun (SOLIS) as boundary condition. Using the resulting three dimensional magnetic field, we calculate the three dimensio...
Method for providing slip energy control in permanent magnet electrical machines
Hsu, John S.
2006-11-14
An electric machine (40) has a stator (43), a permanent magnet rotor (38) with permanent magnets (39) and a magnetic coupling uncluttered rotor (46) for inducing a slip energy current in secondary coils (47). A dc flux can be produced in the uncluttered rotor when the secondary coils are fed with dc currents. The magnetic coupling uncluttered rotor (46) has magnetic brushes (A, B, C, D) which couple flux in through the rotor (46) to the secondary coils (47c, 47d) without inducing a current in the rotor (46) and without coupling a stator rotational energy component to the secondary coils (47c, 47d). The machine can be operated as a motor or a generator in multi-phase or single-phase embodiments and is applicable to the hybrid electric vehicle. A method of providing a slip energy controller is also disclosed.
Electric and magnetic response to the continuum for A=7 isobars in a dicluster model
A. Mason; R. Chatterjee; L. Fortunato; A. Vitturi
2008-11-11
Mirror isobars $^7$Li and $^7$Be are investigated in a dicluster model. The magnetic dipole moments and the magnetic dipole response to the continuum are calculated in this framework. The magnetic contribution is found to be small with respect to electric dipole and quadrupole excitations even at astrophysical energies, at a variance with the case of deuteron. Energy weighted molecular sum rules are evaluated and a formula for the molecular magnetic dipole sum rule is found which matches the numerical calculations. Cross-sections for photo-dissociation and radiative capture as well as the S-factor for reactions of astrophysical significance are calculated with good agreement with known experimental data.
Semiclassical Strings in Electric and Magnetic Fields Deformed $AdS_5 \\times S^5$ Spacetimes
Wung-Hong Huang
2006-01-06
We first apply the transformation of mixing azimuthal and internal coordinate or mixing time and internal coordinate to the 11D M-theory with a stack N M2-branes to find the spacetime of a stack of N D2-branes with magnetic or electric flux in 10 D IIA string theory, after the Kaluza-Klein reduction. We then perform the T duality to the spacetime to find the background of a stack of N D3-branes with magnetic or electric flux. In the near-horizon limit the background becomes the magnetic or electric field deformed $AdS_5 \\times S^5$. We adopt an ansatz to find the classical string solution which is rotating in the deformed $S^5$ with three angular momenta in the three rotation planes. The relations between the classical string energy and its angular momenta are found and results show that the external magnetic and electric fluxes will increase the string energy. Therefore, from the AdS/CFT point of view, the corrections of the anomalous dimensions of operators in the dual SYM theory will be positive. We also investigate the small fluctuations in these solutions and discuss the effects of magnetic and electric fields on the stability of these classical rotating string solutions. Finally, we find the possible solutions of string pulsating on the deformed spacetimes and show that the corrections to the anomalous dimensions of operators in the dual SYM theory are non-negative.
Biological Effects of Electrical and Magnetic Fields: Is It Real?
Durham, M. O.
1993-01-01
Spectrum, August 1990 [9] "EMF, The Debate on Health Effects", EPRI Journal, October/November 1987 [10] "Pursuing the Science of EMF" , EPRI Journal, January/February 1990 Ill]N. Wertheimer and E. Leeper, Electrical Wiring Configurations...
Particle acceleration by fluctuating electric fields at a magnetic field null point
P. Petkaki; A. L. MacKinnon
2007-07-09
Particle acceleration consequences from fluctuating electric fields superposed on an X-type magnetic field in collisionless solar plasma are studied. Such a system is chosen to mimic generic features of dynamic reconnection, or the reconnective dissipation of a linear disturbance. We explore numerically the consequences for charged particle distributions of fluctuating electric fields superposed on an X-type magnetic field. Particle distributions are obtained by numerically integrating individual charged particle orbits when a time varying electric field is superimposed on a static X-type neutral point. This configuration represents the effects of the passage of a generic MHD disturbance through such a system. Different frequencies of the electric field are used, representing different possible types of wave. The electric field reduces with increasing distance from the X-type neutral point as in linear dynamic magnetic reconnection. The resulting particle distributions have properties that depend on the amplitude and frequency of the electric field. In many cases a bimodal form is found. Depending on the timescale for variation of the electric field, electrons and ions may be accelerated to different degrees and often have energy distributions of different forms. Protons are accelerated to $\\gamma$-ray producing energies and electrons to and above hard X-ray producing energies in timescales of 1 second. The acceleration mechanism is possibly important for solar flares and solar noise storms but is also applicable to all collisionless plasmas.
Electric field-induced magnetic switching in Mn:ZnO film
Ren, S. X.; Sun, G. W.; Zhao, J.; Dong, J. Y.; Zhao, X.; Chen, W.; Wei, Y.; Ma, Z. C.
2014-06-09
A large magnetic modulation, accompanied by stable bipolar resistive switching (RS) behavior, was observed in a Mn:ZnO film by applying a reversible electric field. A significant enhancement of the ferromagnetism of the film, to about five times larger than that in the initial (as-grown) state (IS), was obtained by switching the film into the low resistance state. X-ray photoelectron spectroscopy demonstrated the existence of abundant oxygen vacancies in the IS of the film. We suggest that this electric field-induced magnetic switching effect originates with the migration and redistribution of oxygen vacancies during RS. Our work indicates that electric switching is an effective and simple method to increase the ferromagnetism of diluted magnetic oxide films. This provides a promising direction for research in spintronic devices.
Hyperfine structure of the hydroxyl free radical (OH) in electric and magnetic fields
Maeda, Kenji; Carr, Lincoln D
2014-01-01
We investigate single-particle energy spectra of the hydroxyl free radical (OH) in the lowest electronic and rovibrational level under combined static electric and magnetic fields, as an example of heteronuclear polar diatomic molecules. In addition to the fine-structure interactions, the hyperfine interactions and centrifugal distortion effects are taken into account to yield the zero-field spectrum of the lowest ${}^2\\Pi_{3/2}$ manifold to an accuracy of less than 2 kHz. We also examine level crossings and repulsions in the hyperfine structure induced by applied electric and magnetic fields. Compared to previous work, we found more than 10 percent reduction of the magnetic fields at level repulsions in the Zeeman spectrum subjected to a perpendicular electric field. It is important to take into account hyperfine structure when we investigate physics of OH molecules at micro-Kelvin temperatures and below.
Electric/magnetic duality for chiral gauge theories with anomaly cancellation
Jan De Rydt; Torsten T. Schmidt; Mario Trigiante; Antoine Van Proeyen; Marco Zagermann
2009-02-07
We show that 4D gauge theories with Green-Schwarz anomaly cancellation and possible generalized Chern-Simons terms admit a formulation that is manifestly covariant with respect to electric/magnetic duality transformations. This generalizes previous work on the symplectically covariant formulation of anomaly-free gauge theories as they typically occur in extended supergravity, and now also includes general theories with (pseudo-)anomalous gauge interactions as they may occur in global or local N=1 supersymmetry. This generalization is achieved by relaxing the linear constraint on the embedding tensor so as to allow for a symmetric 3-tensor related to electric and/or magnetic quantum anomalies in these theories. Apart from electric and magnetic gauge fields, the resulting Lagrangians also feature two-form fields and can accommodate various unusual duality frames as they often appear, e.g., in string compactifications with background fluxes.
Electrical detection of microwave assisted magnetization reversal by spin pumping
Rao, Siddharth; Subhra Mukherjee, Sankha; Elyasi, Mehrdad; Singh Bhatia, Charanjit; Yang, Hyunsoo, E-mail: eleyang@nus.edu.sg [Department of Electrical and Computer Engineering and NUSNNI, National University of Singapore, Singapore 117576 (Singapore)
2014-03-24
Microwave assisted magnetization reversal has been investigated in a bilayer system of Pt/ferromagnet by detecting a change in the polarity of the spin pumping signal. The reversal process is studied in two material systems, Pt/CoFeB and Pt/NiFe, for different aspect ratios. The onset of the switching behavior is indicated by a sharp transition in the spin pumping voltage. At a threshold value of the external field, the switching process changes from partial to full reversal with increasing microwave power. The proposed method provides a simple way to detect microwave assisted magnetization reversal.
The electric charge and magnetic moment of neutral fundamental particles
Kaushik Bhattacharya
2009-05-27
The article focuses on the issue of the two definitions of charge, mainly the gauge charge and the effective charge of fundamental particles. Most textbooks on classical electromagnetism and quantum field theory only works with the gauge charges while the concept of the induced charge remains unattended. In this article it has been shown that for intrinsically charged particles both of the charges remain the same but there can be situations where an electrically neutral particle picks up some electrical charge from its plasma surrounding. The physical origin and the scope of application of the induced charge concept has been briefly discussed in the article.
Limits on the thermoacoustic detectability of electric and magnetic charges
Akerlof, C.W.
1982-09-01
The energy loss is estimated for a slow magnetic monopole traveling through a conductor. The thermoacoustic signal derived from this process is compared to the acoustic phonon fluctuation pressure. The results show that single-monopole detectability is strongly limited by thermal noise. These calculations also imply severe limits for the detectability of charged-particle cascades.
Gravitational radiation, vorticity and the electric and magnetic part of Weyl tensor
L. Herrera; N. O. Santos; J. Carot
2006-05-15
The electric and the magnetic part of the Weyl tensor, as well as the invariants obtained from them, are calculated for the Bondi vacuum metric. One of the invariants vanishes identically and the other only exhibits contributions from terms of the Weyl tensor containing the static part of the field. It is shown that the necessary and sufficient condition for the spacetime to be purely electric is that such spacetime be static. It is also shown that the vanishing of the electric part implies Minkowski spacetime. Unlike the electric part, the magnetic part does not contain contributions from the static field. Finally a speculation about the link between the vorticity of world lines of observers at rest in a Bondi frame, and gravitational radiation, is presented.
Partitioning of electric and magnetic energy in SU(2) gauge theory
Clifford H. Taubes
2002-01-22
This article provides some estimates for the relative sizes of the electric and magnetic contributions to the energy functional for the minimum energy configuration of an SU(2) gauge field on R^3 in the presence of an source in a fixed ball. The surprising fact is that the contribution to both energies from the free field region increases at worst linearly with the coupling, rather than quadratically. Moreover, the external electric field is severly surpressed outside the source at large coupling while the magnetic field is concentrated in a shell surrounding the source suggesting a classical mechanism for the formation of the 'MIT bag'.
Lagrangians with electric and magnetic charges of N=2 supersymmetric gauge theories
Mathijs de Vroome; Bernard de Wit
2007-07-18
General Lagrangians are constructed for N=2 supersymmetric gauge theories in four space-time dimensions involving gauge groups with (non-abelian) electric and magnetic charges. The charges induce a scalar potential, which, when the charges are regarded as spurionic quantities, is invariant under electric/magnetic duality. The resulting theories are especially relevant for supergravity, but details of the extension to local supersymmetry will be discussed elsewhere. The results include the coupling to hypermultiplets. Without the latter, it is demonstrated how an off-shell representation can be constructed based on vector and tensor supermultiplets.
On the electric and magnetic properties of conductors
Arbab I. Arbab
2010-07-18
Application of the generalized continuity equation reveals that the drift current in conductors is equivalent to a negative diffusion current. A phenomenological model of conductivity is developed using the generalized continuity equations. Consequently, a limiting conductivity is obtained that amounts to $1.09\\times \\,10^9\\,\\Omega^{-1}m^{-1}$. A magnetomotive force (current) is hypothesized to exist, which is exhibited when a voltage changes with time. Magnetic charges and currents are found to be related to displacement current.
Detection of pico-Tesla magnetic fields using magneto-electric sensors at room temperature
Zhai Junyi; Xing Zengping; Dong Shuxiang; Li Jiefang; Viehland, D. [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)
2006-02-06
The measurement of low-frequency (10{sup -2}-10{sup 3} Hz) minute magnetic field variations (10{sup -12} Tesla) at room temperature in a passive mode of operation would be critically enabling for deployable neurological signal interfacing and magnetic anomaly detection applications. However, there is presently no magnetic field sensor capable of meeting all of these requirements. Here, we present new bimorph and push-pull magneto-electric laminate composites, which incorporate a charge compensation mechanism (or bridge) that dramatically enhances noise rejection, enabling achievement of such requirements.
Event-by-event fluctuations of magnetic and electric fields in heavy ion collisions
Adam Bzdak; Vladimir Skokov
2012-03-06
We show that fluctuating proton positions in the colliding nuclei generate, on the event-by-event basis, very strong magnetic and electric fields in the direction both parallel and perpendicular to the reaction plane. The magnitude of E and B fields in each event is of the order of m_pi^2 \\approx 10^18 Gauss. Implications on the observation of electric dipole in heavy ion collisions is discussed, and the possibility of measuring the electric conductivity of the hot medium is pointed out.
Electric field of a point-like charge in a strong magnetic field
A. E. Shabad; V. V. Usov
2006-07-22
We describe the potential produced by a point electric charge placed into a constant magnetic field, so strong that the electron Larmour length is much shorter than its Compton length. The standard Coulomb law is modified due to the vacuum polarization by the external magnetic field. Only mode-2 photons mediate the static interaction. The corresponding vacuum polarization component, taken in the one-loop approximation, grows linearly with the magnetic field. Thanks to this fact a scaling regime occurs in the limit of infinite magnetic field, where the potential is determined by a universal function, independent the magnetic field. The scaling regime implies a short-range character of interaction in the Larmour scale, expressed as a Yukawa law. On the contrary, the electromagnetic interaction regains its long-range character in a larger scale, characterized by the Compton length. In this scale the tail of the Yukawa potential follows an anisotropic Coulomb law: it decreases as the distance from the charge increases, slower along the magnetic field and faster across. The equipotential surface is an ellipsoid stretched along the magnetic field. As a whole, the modified Coulomb potential is a narrower-shaped function than the standard Coulomb function, the narrower the stronger the field. The singular behavior in the vicinity of the charge remains unsuppressed by the magnetic field. These results may be useful for studying atomic spectra in super- strong magnetic fields of several Schwinger's characteristic values.
Hydrogen atom in crossed electric and magnetic fields: Phase space topology and torus quantization for the periodic orbits in a strongly coupled multidimen- sional Hamiltonian system, namely the hydrogen atom.15.Gy, 05.45.-a, 45.20.Jj I. INTRODUCTION The hydrogen atom in crossed electric and magnetic fields
Lathrop, Daniel P.
FINAL Syllabus for Physics 260 - Fall 2014 General Physics: Vibrations, Waves, Heat, Electricity, and Magnetism Professor Daniel Lathrop - Sections 0101 through 0106 Official Course Description: General Physics), or PHYS272. Second semester of a three-semester calculus-based general physics course. Vibrations, waves
pressure changes with the mass density as roughly 4/3 , and the Joule heating rate goes as roughly for dynamical, secular, and pulsational stability, but the Joule heating rate directly affects the secularANALYTIC CRITERIA FOR THE MECHANICAL AND THERMAL STABILITY OF MAGNETIC STARS WITH FINITE ELECTRICAL
Electric-Magnetic duality and the "Loop Representation" in Abelian Gauge Theories
Lorenzo Leal
1996-03-01
Abelian Gauge Theories are quantized in a geometric representation that generalizes the Loop Representation and treates electric and magnetic operators on the same footing. The usual canonical algebra is turned into a topological algebra of non local operators that resembles the order-disorder dual algebra of 't Hooft. These dual operators provide a complete description of the physical phase space of the theories.
Impedance operator description of a meta--surface with electric and magnetic dipoles
Didier Felbacq
2015-07-28
A meta-surface made of a collection of nano-resonators characterized an electric dipole and a magnetic dipole was studied in the regime where the wavelength is large with respect to the size of the resonators. An effective description in terms of an impedance operator was derived.
Electric charge in the field of a magnetic event in three-dimensional spacetime
Claudio Bunster; Cristian Martinez
2012-02-09
We analyze the motion of an electric charge in the field of a magnetically charged event in three-dimensional spacetime. We start by exhibiting a first integral of the equations of motion in terms of the three conserved components of the spacetime angular momentum, and then proceed numerically. After crossing the light cone of the event, an electric charge initially at rest starts rotating and slowing down. There are two lengths appearing in the problem: (i) the characteristic length $\\frac{q g}{2 \\pi m}$, where $q$ and $m$ are the electric charge and mass of the particle, and $g$ is the magnetic charge of the event; and (ii) the spacetime impact parameter $r_0$. For $r_0 \\gg \\frac{q g}{2 \\pi m}$, after a time of order $r_0$, the particle makes sharply a quarter of a turn and comes to rest at the same spatial position at which the event happened in the past. This jump is the main signature of the presence of the magnetic event as felt by an electric charge. A derivation of the expression for the angular momentum that uses Noether's theorem in the magnetic representation is given in the Appendix.
Learning physics in context: a study of student learning about electricity and magnetism
Colorado at Boulder, University of
re-centres the discussion of student learning in physics to focus on context. In order to do soLearning physics in context: a study of student learning about electricity and magnetism This paper and inextricable role of context in student learning. This work sits within a broader effort to create and analyze
Chung, Deborah D.L.
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 electrical resistivity below 10 X cm, as provided by conductive fillers, which contribute to shielding
Cheng, Hongguang, E-mail: chenghg7932@gmail.com; Deng, Ning [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)] [Institute of Microelectronics, Tsinghua University, Beijing 100084 (China)
2013-12-15
We investigated the influence of thermal agitation on the electric field induced precessional magnetization switching probability with perpendicular easy axis by solving the Fokker-Planck equation numerically with finite difference method. The calculated results show that the thermal agitation during the reversal process crucially influences the switching probability. The switching probability can be achieved is only determined by the thermal stability factor ? of the free layer, it is independent on the device dimension, which is important for the high density device application. Ultra-low error rate down to the order of 10{sup ?9} can be achieved for the device of thermal stability factor ? of 40. Low damping factor ? material should be used for the free layer for high reliability device applications. These results exhibit potential of electric field induced precessional magnetization switching with perpendicular easy axis for ultra-low power, high speed and high density magnetic random access memory (MRAM) applications.
Enhanced magnetic and electrical properties in amorphous Ge:Mn thin films by non-magnetic codoping
Yin Wenjing; Kell, Copeland D.; Duska, Chris; Lu Jiwei; Floro, Jerrold A. [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); He Li; Hull, Robert [Department of Materials Science and Engineering, Rensselaer Polytechnic Institute, Troy, New York 12180 (United States); Dolph, Melissa C. [Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States); Wolf, Stuart A. [Department of Materials Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States); Department of Physics, University of Virginia, Charlottesville, Virginia 22904 (United States)
2012-02-01
Amorphous Ge{sub 1-x}Mn{sub x} thin films have been prepared by co-depositing Ge and Mn on SiO{sub 2}/Si using an ultrahigh vacuum molecular beam epitaxy system. Across a range of growth temperatures and Mn concentrations (2.8 at. %, 10.9 at. %, and 21.3 at. %), we achieved enhanced magnetic and electrical properties with non-magnetic codopants dispersed in the films. Self-assembled Mn-rich amorphous nanostructures were observed in the amorphous Ge matrix, either as isolated nanoclusters or as nanocolumns, depending on Mn concentration. The ferromagnetic saturation moments were found to increase with Mn concentration and reached a maximum of 0.7 {mu}{sub B}/Mn in the as-grown samples. Two magnetic transition temperatures around 15 K and 200 K were observed in these amorphous MBE-grown samples. Coercivity is considered within the context of local magnetic anisotropy. The anomalous Hall effect confirmed a strong correlation between the magnetization and transport properties, indicating that global ferromagnetic coupling was carrier-mediated rather than through direct exchange. In addition, negative magnetoresistance was detected from 5 K to room temperature.
Janiszewski, Stefan
2015-01-01
Detailed knowledge about equilibration processes is of interest for various fields of physics, including heavy ion collision experiments and quantum quenched condensed matter systems. We study the approach to equilibrium at late times within two types of strongly coupled thermal systems in 3+1 dimensions: systems in the presence of (i) a non-zero charge density, or (ii) a magnetic field at vanishing charge density. Utilizing the gauge/gravity correspondence, we map the aforementioned problem to the computation of quasinormal frequencies around two particular classes of black branes within the Einstein-Maxwell theory. We compute (i) the tensor quasinormal modes of Reissner-Nordstr\\"om black branes and (ii) the scalar, as well as tensor quasinormal modes of magnetic black branes. Some of these quasinormal modes correspond to the late-time relaxation of the above systems after starting with initial pressure anisotropy. We provide benchmarks which need to be matched at late times by all holographic thermalization...
Dynamic frequency tuning of electric and magnetic metamaterial response
O'Hara, John F; Averitt, Richard; Padilla, Willie; Chen, Hou-Tong
2014-09-16
A geometrically modifiable resonator is comprised of a resonator disposed on a substrate, and a means for geometrically modifying the resonator. The geometrically modifiable resonator can achieve active optical and/or electronic control of the frequency response in metamaterials and/or frequency selective surfaces, potentially with sub-picosecond response times. Additionally, the methods taught here can be applied to discrete geometrically modifiable circuit components such as inductors and capacitors. Principally, controlled conductivity regions, using either reversible photodoping or voltage induced depletion activation, are used to modify the geometries of circuit components, thus allowing frequency tuning of resonators without otherwise affecting the bulk substrate electrical properties. The concept is valid over any frequency range in which metamaterials are designed to operate.
Towards a non-abelian electric-magnetic symmetry: the skeleton group
L. Kampmeijer; F. A. Bais; B. J. Schroers; J. K. Slingerland
2010-07-02
We propose an electric-magnetic symmetry group in non-abelian gauge theory, which we call the skeleton group. We work in the context of non-abelian unbroken gauge symmetry, and provide evidence for our proposal by relating the representation theory of the skeleton group to the labelling and fusion rules of charge sectors. We show that the labels of electric, magnetic and dyonic sectors in non-abelian Yang-Mills theory can be interpreted in terms of irreducible representations of the skeleton group. Decomposing tensor products of these representations thus gives a set of fusion rules which contain information about the full fusion rules of these charge sectors. We demonstrate consistency of the skeleton's fusion rules with the known fusion rules of the purely electric and purely magnetic magnetic sectors, and extract new predictions for the fusion rules of dyonic sectors in particular cases. We also implement S-duality and show that the fusion rules obtained from the skeleton group commute with S-duality.
Study of the electric field formation in a multi-cusped magnetic field
Liu, Hui, E-mail: hlying@gmail.com; Yu, Daren, E-mail: yudaren@hit.edu.cn [Lab of Plasma Propulsion, Mail Box 458, Harbin Institute of Technology (HIT), Harbin 150001 (China); Wu, Huan; Zhao, Yinjian; Ma, Chengyu; Wang, Di; Wei, Haoyu [School of Energy Science and Engineering, Harbin Institute of Technology (HIT), Harbin 150001 (China)
2014-09-15
The multi-cusped field thruster is a kind of electric thruster adopting a cusped magnetic field to achieve a potentially longer lifetime. It is observed in some experiments that the main electric potential drop forms near the exhaust plane, but the formation mechanism of the electric field in this kind of thrusters is not fully clear yet. Based on the analysis of the electron movement, a 2D Particle-in-Cell plus Monte Carlo model is built to reveal the difference of the constraint to electrons between the central leak path and the lateral region of the thruster. Electron trajectories from cathode are analyzed furthermore. It is found that the central leak path inside the discharge channel may play a significant role in the formation of the main electric potential drop near the exhaust plane.
Chu, Shih-I
in crossed magnetic and electric fields Xiao-Min Tong and Shih-I Chu Department of Chemistry, University time-dependent study of three- dimensional Rydberg H atoms in crossed magnetic and electric fields magnetic and electric fields has attracted considerable attention in the last several years both
Electrical Core Transformer for Grid Improvement Incorporating Wire Magnetic Components
Harrie R. Buswell, PhD; Dennis Jacobs, PhD; Steve Meng
2012-03-26
The research reported herein adds to the understanding of oil-immersed distribution transformers by exploring and demonstrating potential improvements in efficiency and cost utilizing the unique Buswell approach wherein the unit is redesigned, replacing magnetic sheet with wire allowing for improvements in configuration and increased simplicity in the build process. Exploration of new designs is a critical component in our drive to assure reduction of energy waste, adequate delivery to the citizenry, and the robustness of U.S. manufacturing. By moving that conversation forward, this exploration adds greatly to our base of knowledge and clearly outlines an important avenue for further exploration. This final report shows several advantages of this new transformer type (outlined in a report signed by all of our collaborating partners and included in this document). Although materials development is required to achieve commercial potential, the clear benefits of the technology if that development were a given is established. Exploration of new transformer types and further work on the Buswell design approach is in the best interest of the public, industry, and the United States. Public benefits accrue from design alternatives that reduce the overall use of energy, but it must be acknowledged that new DOE energy efficiency standards have provided some assurance in that regard. Nonetheless the burden of achieving these new standards has been largely shifted to the manufacturers of oil-immersed distribution transformers with cost increasing up to 20% of some units versus 2006 when this investigation was started. Further, rising costs have forced the industry to look closely are far more expensive technologies which may threaten U.S. competitiveness in the distribution transformer market. This concern is coupled with the realization that many units in the nation's grid are beyond their optimal life which suggests that the nation may be headed for an infrastructure crisis that U.S. industry is ill prepared to handle which could further challenge U.S. competitiveness.
S. Afach; C. A. Baker; G. Ban; G. Bison; K. Bodek; Z. Chowdhuri; M. Daum; M. Fertl; B. Franke; P. Geltenbort; K. Green; M. G. D. van der Grinten; Z. Grujic; P. G. Harris; W. Heil; V. Hélaine; R. Henneck; M. Horras; P. Iaydjiev; S. N. Ivanov; M. Kasprzak; Y. Kermaïdic; K. Kirch; P. Knowles; H. -C. Koch; S. Komposch; A. Kozela; J. Krempel; B. Lauss; T. Lefort; Y. Lemière; A. Mtchedlishvili; O. Naviliat-Cuncic; J. M. Pendlebury; F. M. Piegsa; G. Pignol; P. N. Prashant; G. Quéméner; D. Rebreyend; D. Ries; S. Roccia; P. Schmidt-Wellenburg; N. Severijns; A. Weis; E. Wursten; G. Wyszynski; J. Zejma; J. Zenner; G. Zsigmond
2015-08-03
We report on the measurement of a Larmor frequency shift proportional to the electric-field strength for $^{199}{\\rm Hg}$ atoms contained in a volume permeated with aligned magnetic and electric fields. This shift arises from the interplay between the inevitable magnetic field gradients and the motional magnetic field. The proportionality to electric-field strength makes it apparently similar to an electric dipole moment (EDM) signal, although unlike an EDM this effect is P- and T-conserving. We have used a neutron magnetic resonance EDM spectrometer, featuring a mercury co-magnetometer and an array of external cesium magnetometers, to measure the shift as a function of the applied magnetic field gradient. Our results are in good agreement with theoretical expectations.
On The Interaction of Gravitational Waves with Magnetic and Electric Fields
C. Barrabes; P. A. Hogan
2010-03-02
The existence of large--scale magnetic fields in the universe has led to the observation that if gravitational waves propagating in a cosmological environment encounter even a small magnetic field then electromagnetic radiation is produced. To study this phenomenon in more detail we take it out of the cosmological context and at the same time simplify the gravitational radiation to impulsive waves. Specifically, to illustrate our findings, we describe the following three physical situations: (1) a cylindrical impulsive gravitational wave propagating into a universe with a magnetic field, (2) an axially symmetric impulsive gravitational wave propagating into a universe with an electric field and (3) a `spherical' impulsive gravitational wave propagating into a universe with a small magnetic field. In cases (1) and (3) electromagnetic radiation is produced behind the gravitational wave. In case (2) no electromagnetic radiation appears after the wave unless a current is established behind the wave breaking the Maxwell vacuum. In all three cases the presence of the magnetic or electric fields results in a modification of the amplitude of the incoming gravitational wave which is explicitly calculated using the Einstein--Maxwell vacuum field equations.
Interaction between a stationary electric charge and a stationary magnetic dipole
W. B. Bonnor
2002-03-13
Using Einstein-Maxwell theory I investigate the gravitational field generated by an electric charge and a magnetic dipole, both held in fixed positions, but spinning with prescribed angular momenta. There is a conical singularity between them representing a strut balancing the gravitational attraction of their masses. However, there is in general another singularity, which I call a torsion singularity. I interpret this as a couple needed to maintain the spins at their prescribed values. It vanishes when the parameters obey a certain formula. A conclusion of the work is that the charge and the magnet must spin relative to one another unless constrained by a couple.
Dynamical view of pair creation in uniform electric and magnetic fields
Naoto Tanji
2009-05-12
Pair creation in a uniform classical electromagnetic field (Schwinger mechanism) is studied focusing on the time evolution of the distribution of created particles. The time evolution of the distribution in time-dependent fields is also presented as well as effects of back reaction. Motivated by the Glasma flux tube, which may be formed at the initial stage of heavy-ion collisions, we investigate effects of a magnetic field parallel to an electric field, and find that the magnetic field makes the evolution of a fermion system faster.
El-Refaie, Ayman Mohamed Fawzi (Niskayuna, NY); Reddy, Patel Bhageerath (Madison, WI)
2012-07-17
An interior permanent magnet electric machine is disclosed. The interior permanent magnet electric machine comprises a rotor comprising a plurality of radially placed magnets each having a proximal end and a distal end, wherein each magnet comprises a plurality of magnetic segments and at least one magnetic segment towards the distal end comprises a high resistivity magnetic material.
Quantum decoherence of spin states in an electric-field controllable single molecular magnet
Xiang Hao; Chen Liu; Shiqun Zhu
2012-08-08
The time evolution of low energy spin states of a single molecular magnet in a local electric field is investigated. The decoherence of the driven single molecular magnet weakly coupled to a thermal bosonic environment is analyzed by the second-order time-convolutionless non-Markovian master equation. If the characteristic time of the system is much smaller than the correlation time of the environment, the analytical expression of the reduced density matrix of the system is obtained. The non-Markovian dynamics of the spin states at low temperatures is induced by the memory effects in the decay rates. The non-Markovian oscillation of the Bloch vector is presented. The quantum decoherence can be effectively restrained with the help of the reasonable manipulation of the environment spectral density function and local electric field. The influence of the dissipation on the pointer states are investigated by the von Neumann entropy. The pointer states can be selected by the environment.
Analytical modeling of a new disc permanent magnet linear synchronous machine for electric vehicles
Liu, C.T.; Chen, J.W.; Su, K.S.
1999-09-01
This paper develops an analytical approach based on a qd0 reference frame model to analyze dynamic and steady state characteristics of disc permanent magnet linear synchronous machines (DPMLSMs). The established compact mathematical model can be more easily employed to analyze the system behavior and to design the controller. Superiority in operational electromagnetic characteristics of the proposed DPMLSM for electric vehicle (EV) applications is verified by both numerical simulations and experimental investigations.
CHARLES M. WEBER
2008-06-24
As an outgrowth of the Technology Reinvestment Program of the 1990’s, an Agreement was formed between BWXT and the DOE to promote the commercialization of Superconducting Magnetic Energy Storage (SMES) technology. Business and marketing studies showed that the performance of electric transmission lines could be improved with this SMES technology by stabilizing the line thereby allowing the reserved stability margin to be used. One main benefit sought was to double the capacity and the amount of energy flow on an existing transmission line by enabling the use of the reserved stability margin, thereby doubling revenue. Also, electrical disturbances, power swings, oscillations, cascading disturbances and brown/black-outs could be mitigated and rendered innocuous; thereby improving power quality and reliability. Additionally, construction of new transmission lines needed for increased capacity could be delayed or perhaps avoided (with significant savings) by enabling the use of the reserved stability margin of the existing lines. Two crucial technical aspects were required; first, a large, powerful, dynamic, economic and reliable superconducting magnet, capable of oscillating power flow was needed; and second, an electrical power interface and control to a transmission line for testing, demonstrating and verifying the benefits and features of the SMES system was needed. A project was formed with the goals of commercializing the technology by demonstrating SMES technology for utility applications and to establish a domestic capability for manufacturing large superconducting magnets for both commercial and defense applications. The magnet had very low AC losses to support the dynamic and oscillating nature of the stabilizing power flow. Moreover, to economically interface to the transmission line, the magnet had the largest operating voltage ever made. The manufacturing of that design was achieved by establishing a factory with newly designed and acquired equipment, tooling, methods and skilled personnel. The final magnet system measured 14 feet in diameter, 10 feet in height, and weighed about 35 tons. The superconducting magnet and design technology was successfully implemented and demonstrated. The project was not successfully concluded however; as the critical planned final demonstration was not achieved. The utilities could not understand or clarify their future business needs and the regulatory requirements, because of the deregulation policies and practices of the country. Much uncertainty existed which prevented utilities from defining business plans, including asset allocation and cost recovery. Despite the technical successes and achievements, the commercial development could not be implemented and achieved. Thus, the demonstration of this enhancement to the utility’s transmission system and to the reliability of the nation’s electrical grid was not achieved. The factory was ultimately discontinued and the technology, equipment and product were placed in storage.
Anan, T.; Ichimoto, K.; Casini, R. E-mail: ichimoto@kwasan.kyoto-u.ac.jp
2014-05-10
Magnetic fields govern the plasma dynamics in the outer layers of the solar atmosphere, and electric fields acting on neutral atoms that move across the magnetic field enable us to study the dynamical coupling between neutrals and ions in the plasma. In order to measure the magnetic and electric fields of chromospheric jets, the full Stokes spectra of the Paschen series of neutral hydrogen in a surge and in some active region jets that took place at the solar limb were observed on 2012 May 5, using the spectropolarimeter of the Domeless Solar Telescope at Hida observatory, Japan. First, we inverted the Stokes spectra taking into account only the effect of magnetic fields on the energy structure and polarization of the hydrogen levels. Having found no definitive evidence of the effects of electric fields in the observed Stokes profiles, we then estimated an upper bound for these fields by calculating the polarization degree under the magnetic field configuration derived in the first step, with the additional presence of a perpendicular (Lorentz type) electric field of varying strength. The inferred direction of the magnetic field on the plane of the sky approximately aligns to the active region jets and the surge, with magnetic field strengths in the range 10 G < B < 640 G for the surge. Using magnetic field strengths of 70, 200, and 600 G, we obtained upper limits for possible electric fields of 0.04, 0.3, and 0.8 V cm{sup –1}, respectively. This upper bound is conservative, since in our modeling we neglected the possible contribution of collisional depolarization. Because the velocity of neutral atoms of hydrogen moving across the magnetic field derived from these upper limits of the Lorentz electric field is far below the bulk velocity of the plasma perpendicular to the magnetic field as measured by the Doppler shift, we conclude that the neutral atoms must be highly frozen to the magnetic field in the surge.
Photon Self-Energy and Electric Susceptibility in a Magnetized Three-flavor Color Superconductor
Bo Feng; Efrain J. Ferrer; Vivian de la Incera
2012-03-07
We study the photon self-energy for the in-medium photon in a three-flavor color superconductor in the presence of a magnetic field. At strong magnetic field, the quark dynamics becomes $(1+1)$-dimensional and the self-energy tensor only has longitudinal components. In this approximation there is no Debye or Meissner screenings at zero temperature, but the electric susceptibility is nonzero and highly anisotropic. In the direction transverse to the applied field, the electric susceptibility is the same as in vacuum, while in the longitudinal direction it depends on the magnitude of the magnetic field. Such a behavior is a realization in cold-dense QCD of the magnetoelectric effect, which was first discovered in condensed matter physics. The magnetic permeability remains equal to that in vacuum for both transverse and longitudinal components. We discuss the importance of the Pauli-Villars regularization to get meaningful physical results in the infrared limit of the polarization operator. We also find the covariant form of the polarization operator in the reduced (1+1)-D space of the lowest Landau level and proves its transversality.
Jeong, J. H.; Endoh, T.; Kim, Y.; Kim, W. K.; Park, S. O.
2014-05-07
To identify the degradation mechanism in magnetic tunnel junctions (MTJs) using hydrogen, the properties of the MTJs were measured by applying an additional hydrogen etch process and a hydrogen plasma process to the patterned MTJs. In these studies, an additional 50?s hydrogen etch process caused the magnetoresistance (MR) to decrease from 103% to 14.7% and the resistance (R) to increase from 6.5?k? to 39?k?. Moreover, an additional 500?s hydrogen plasma process decreased the MR from 103% to 74% and increased R from 6.5?k? to 13.9?k?. These results show that MTJs can be damaged by the hydrogen plasma process as well as by the hydrogen etch process, as the atomic bonds in MgO may break and react with the exposed hydrogen gas. Compounds such as MgO hydrate very easily. We also calculated the damaged layer width (DLW) of the patterned MTJs after the hydrogen etching and plasma processes, to evaluate the downscaling limitations of spin-transfer-torque magnetic random-access memory (STT-MRAM) devices. With these calculations, the maximum DLWs at each side of the MTJ, generated by the etching and plasma processes, were 23.8?nm and 12.8?nm, respectively. This result validates that the hydrogen-based MTJ patterning processes cannot be used exclusively in STT-MRAMs beyond 20?nm.
Y. Maezawa; S. Aoki; S. Ejiri; T. Hatsuda; N. Ishii; K. Kanaya; N. Ukita; T. Umeda
2010-05-11
Screenings of the quark-gluon plasma in electric and magnetic sectors are studied on the basis of generalized Polyakov-line correlation functions in lattice QCD simulations with two flavors of improved Wilson quarks. Using the Euclidean-time reflection ($\\R$) and the charge conjugation ($\\Ca$), electric and magnetic screening masses are extracted in a gauge invariant manner. Long distance behavior of the standard Polyakov-line correlation in the quark-gluon plasma is found to be dictated by the magnetic screening. Also, ratio of the two screening masses agrees with that obtained from the dimensionally-reduced effective field theory and the ${\\cal N}=4$ supersymmetric Yang-Mills theory.
Spectrum of Magnetic Dissipation and Horizontal Electric Currents in the Solar Photosphere
Valentyna Abramenko
2008-06-09
A proxy for horizontal electric currents in the solar photosphere was suggested. For a set of evolving active regions (ARs) observed with {\\it Solar and Heliospheric Observatory (SOHO)} Michelson Doppler Imager (MDI) in the high resolution mode, the dissipation spectrum, $k^2E(k)$, and the spatial structure of dissipation, i.e., the Stokes dissipation function $\\epsilon(x,y)$, were calculated from the observed $B_z$ component of the magnetic field. These functions allowed us to calculate (a part of) the horizontal electric current density in the photosphere. It was shown that as an active region emerges, large-scale horizontal electric currents are gradually generated and determine a bulk of dissipation. When an active region decays, the large-scale horizontal currents decay faster than the small-scale ones. The density of horizontal currents in active regions is in the range of $ \\sim (0.008 - 0.028)$ A/m$^2$, that is compatible with the density of vertical currents in active regions. We suggest two possible mechanisms for generation of such horizontal currents in the photosphere. One of them is the drift motions of charged particles in the medium of varying plasma pressure gradient in a horizontal plane at the periphery of a sunspot. Such a drift can produce quasi-circular closed horizontal currents around sunspots. Another possibility could be an existence of horizontal axial current inside a highly twisted horizontal magnetic structure laying in the photosphere along the magnetic neutral line. The horizontal currents may contribute significantly to the dynamics of the photosphere/corona coupling, as well as the estimation of non-potentiality of ARs.
Berry Phase for Systems with Angular Momenta in Electric and Magnetic Fields
K. J. B. Ghosh; D. De Munshi; B. Dutta-Roy
2011-04-28
The Berry phase for a variety of systems comprising of two angular momenta is discussed. These include the electron and proton in the ground state of the hydrogen atom (taking into account the hyperfine interaction), the positronium atom, the spin and orbital angular momenta of a single electron, muon capture by the deuteron in an external magnetic field, etc. Though the time scales involved, the underlying intrinsic Hamiltonians are quite different, as also the possible experimental probes, the geometric nature of the results for the Berry phase due to a time varying externally imposed magnetic field is found to be quite robust. Some indications are also put forward as to the possible interesting studies with time varying electric fields. The objective of this work is an attempt to broaden the scope of such studies in both the experimental and theoretical directions.
Entanglement of magnetic impurities through electron scattering in an electric field
Oscar Lazo-Arjona; Guillermo Cordourier-Maruri; Romeo de Coss
2015-07-11
We show that the entanglement between two distant magnetic impurities, generated via electron scattering, can be easily modulated by controlling the magnitude of an applied external electric field. We assume that the two magnetic impurities are fixed and located on an one-dimensional quantum wire. A ballistic electron moving through the wire is scattered off by both impurities, so the electron spin can be seen as a mediator between the spins of the impurities. Heisenberg operators are used to describe the interactions between electron and impurities spins. We use a wave guide formalism to model the ballistic electron wave-function. Entanglement control is shown to be possible for three different protocols of entanglement detection. The effect of detection protocols on the entanglement extraction is discussed.
High-precision determination of the electric and magnetic form factors of the proton
J. C. Bernauer; P. Achenbach; C. Ayerbe Gayoso; R. Böhm; D. Bosnar; L. Debenjak; M. O. Distler; L. Doria; A. Esser; H. Fonvieille; J. M. Friedrich; J. Friedrich; M. Gómez Rodríguez de la Paz; M. Makek; H. Merkel; D. G. Middleton; U. Müller; L. Nungesser; J. Pochodzalla; M. Potokar; S. Sánchez Majos; B. S. Schlimme; S. Širca; Th. Walcher; M. Weinriefer
2010-12-13
New precise results of a measurement of the elastic electron-proton scattering cross section performed at the Mainz Microtron MAMI are presented. About 1400 cross sections were measured with negative four-momentum transfers squared up to Q^2=1 (GeV/c)^2 with statistical errors below 0.2%. The electric and magnetic form factors of the proton were extracted by fits of a large variety of form factor models directly to the cross sections. The form factors show some features at the scale of the pion cloud. The charge and magnetic radii are determined to be r_E=0.879(5)(stat.)(4)(syst.)(2)(model)(4)(group) fm and r_M=0.777(13)(stat.)(9)(syst.)(5)(model)(2)(group) fm.
Magnetic and electric contributions to the energy loss in a dynamical QCD medium
Magdalena Djordjevic
2011-05-21
The computation of radiative energy loss in a finite size QCD medium with dynamical constituents is a key ingredient for obtaining reliable predictions for jet quenching in ultra-relativistic heavy ion collisions. It was previously shown that energy loss in dynamical QCD medium is significantly higher compared to static QCD medium. To understand this difference, we here analyze magnetic and electric contributions to energy loss in dynamical QCD medium. We find that the significantly higher energy loss in the dynamical case is entirely due to appearance of magnetic contribution in the dynamical medium. While for asymptotically high energies, the energy loss in static and dynamical medium approach the same value, we find that the physical origin of the energy loss in these two cases is different.
Electric and magnetic fields research and public information dissemination program. Progress report
NONE
1995-12-01
The Electric and Magnetic Fields (EMF) Research and Public Information Dissemination (RAPID) Program was authorized by the Energy Policy Act of 1992 (enacted October 24, 1992) to determine whether or not exposure to EMF produced by the generation, transmission, and use of electric energy affects human health. Two Federal agencies, the Department of Energy (DOE) and the National Institute of Environmental Health Sciences (NIEHS), have primary responsibility for the program, but other Federal agencies are key participants as well. This program requires that Federal appropriations be matched by contributions from non-Federal sources. The authorized level of funding for the program was $65 million over a 5-year period (fiscal years 1993-1997 inclusive). For EMF RAPID to be a fully funded program, $32.5 million over 5 years will have to be appropriated by Congress and matched by non-Federal contributions.
Goyal, Amit (Knoxville, TN), Kang; Sukill (Knoxville, TN)
2012-02-21
Novel articles and methods to fabricate same with self-assembled nanodots and/or nanorods of a single or multicomponent material within another single or multicomponent material for use in electrical, electronic, magnetic, electromagnetic and electrooptical devices is disclosed. Self-assembled nanodots and/or nanorods are ordered arrays wherein ordering occurs due to strain minimization during growth of the materials. A simple method to accomplish this when depositing in-situ films is also disclosed. Device applications of resulting materials are in areas of superconductivity, photovoltaics, ferroelectrics, magnetoresistance, high density storage, solid state lighting, non-volatile memory, photoluminescence, thermoelectrics and in quantum dot lasers.
A. Rossani; A. M. Scarfone
2009-03-05
The linear Boltzmann equation for elastic and/or inelastic scattering is applied to derive the distribution function of a spatially homogeneous system of charged particles spreading in a host medium of two-level atoms and subjected to external electric and/or magnetic fields. We construct a Fokker-Planck approximation to the kinetic equations and derive the most general class of distributions for the given problem by discussing in detail some physically meaningful cases. The equivalence with the transport theory of electrons in a phonon background is also discussed.
Electric-Magnetic Duality in IIB Matrix Model with D-brane
Hiroyuki Takata
2000-08-02
We consider electric-magnetic duality(S-duality) in IIB matrix model with a D3-brane background. We propose the duality transformation by considering that of noncommutative Yang-Mills theory(NCYM) in four dimension. NCYM derived from the matrix model has a Yang-Mills coupling related to the noncommutativity of the spacetime. We argue that open strings bits as bi-local fields on the spacetime are decoupled from the bulk in NCOS decoupling limits as it is in string theory approach. We also discuss how our four dimensional spacetime relates to higher, by applying the decoupling and the commutative limits of the backgrounds of the matrix model.
Propagator of a Charged Particle with a Spin in Uniform Magnetic and Perpendicular Electric Fields
Ricardo Cordero-Soto; Raquel M. Lopez; Erwin Suazo; Sergei K. Suslov
2008-02-05
We construct an explicit solution of the Cauchy initial value problem for the time-dependent Schroedinger equation for a charged particle with a spin moving in a uniform magnetic field and a perpendicular electric field varying with time. The corresponding Green function (propagator) is given in terms of elementary functions and certain integrals of the fields with a characteristic function, which should be found as an analytic or numerical solution of the equation of motion for the classical oscillator with a time-dependent frequency. We discuss a particular solution of a related nonlinear Schroedinger equation and some special and limiting cases are outlined.
Semi-soft Nematic Elastomers and Nematics in Crossed Electric and Magnetic Fields
Fangfu Ye; Ranjan Mukhopadhyay; Olaf Stenull; T. C. Lubensky
2007-05-11
Nematic elastomers with a locked-in anisotropy direction exhibit semi-soft elastic response characterized by a plateau in the stress-strain curve in which stress does not change with strain. We calculate the global phase diagram for a minimal model, which is equivalent to one describing a nematic in crossed electric and magnetic fields, and show that semi-soft behavior is associated with a broken symmetry biaxial phase and that it persists well into the supercritical regime. We also consider generalizations beyond the minimal model and find similar results.
Modeling electron transport in the presence of electric and magnetic fields.
Fan, Wesley C.; Drumm, Clifton Russell; Pautz, Shawn D.; Turner, C. David
2013-09-01
This report describes the theoretical background on modeling electron transport in the presence of electric and magnetic fields by incorporating the effects of the Lorentz force on electron motion into the Boltzmann transport equation. Electromagnetic fields alter the electron energy and trajectory continuously, and these effects can be characterized mathematically by differential operators in terms of electron energy and direction. Numerical solution techniques, based on the discrete-ordinates and finite-element methods, are developed and implemented in an existing radiation transport code, SCEPTRE.
Masashi Kuniyasu
2015-01-27
New solutions are derived in the $2+1$ gravity which is coupled to $|{\\cal F}|^k$ type non-linear electric field in Maxwell Power theory with dilaton field. We obtain consistent solutions in general $k$ case. We also investigate the behavior of the metric function with the space-time singularity. Then, we found some black hole solutions when the space-time has a singular point at $r=0$. Addition, we derive the Brown-York mass when the space-time represents black hole.
Anderson, L.E.
1994-03-01
There is now convincing evidence from a large number of laboratories, that exposure to extremely low frequency (ELF) magnetic and electric fields produces biological responses in animals. Many of the observed effects appear to be directly or indirectly associated with the neural or neuroendocrine systems. Such effects include increased neuronal excitability, chemical and hormonal changes in the nervous system, altered behavioral responses, some of which are related to sensing the presence of the field, and changes in endogenous biological rhythms. Additional indices of general physiological status appear relatively unaffected by exposure, although effects have occasionally been described in bone growth and fracture repair, reproduction and development, and immune system function. A major current emphasis in laboratory research is to determine whether or not the reported epidemiological studies that suggest an association between EMF exposure and risk of cancer are supported in studies using animal models. Three major challenges exist for ongoing research: (1) knowledge about the mechanisms underlying observed bioeffects is incomplete, (2) researchers do not as yet understand what physical aspects of exposure produce biological responses, and (3) health consequences resulting from ELF exposure are unknown. Although no animal studies clearly demonstrate deleterious effects of ELF fields, several are suggestive of potential health impacts. From the perspective of laboratory animal studies, this paper will discuss biological responses to ELF magnetic and/or electric field exposures.
Frischauf, Norbert [QASAR Technologie(s) GmbH, Johann Gottekgasse 39, A-1230, Vienna (Austria); Hettmer, Manfred; Grassauer, Andreas; Bartusch, Tobias [QASAR Technologie(s) GmbH, Johann Gottekgasse 39, A-1230, Vienna (Austria); Koudelka, Otto [Institute of Communication Networks and Satellite Communication, Graz University of Technology, Inffeldgasse 12/I, A-8010 Graz (Austria)
2006-07-01
More than 60 years after the later Nobel laureate Hannes Alfven had published a letter stating that oscillating magnetic fields can accelerate ionised matter via magneto-hydrodynamic interactions in a wave like fashion, the technical implementation of Alfven waves for propulsive purposes has been proposed, patented and examined for the first time by a group of inventors. The name of the concept, utilising Alfven waves to accelerate ionised matter for propulsive purposes, is MOA - Magnetic field Oscillating Amplified thruster. Alfven waves are generated by making use of two coils, one being permanently powered and serving also as magnetic nozzle, the other one being switched on and off in a cyclic way, deforming the field lines of the overall system. It is this deformation that generates Alfven waves, which are in the next step used to transport and compress the propulsive medium, in theory leading to a propulsion system with a much higher performance than any other electric propulsion system. Based on computer simulations, which were conducted to get a first estimate on the performance of the system, MOA is a highly flexible propulsion system, whose performance parameters might easily be adapted, by changing the mass flow and/or the power level. As such the system is capable to deliver a maximum specific impulse of 13116 s (12.87 mN) at a power level of 11.16 kW, using Xe as propellant, but can also be attuned to provide a thrust of 236.5 mN (2411 s) at 6.15 kW of power. While space propulsion is expected to be the prime application for MOA and is supported by numerous applications such as Solar and/or Nuclear Electric Propulsion or even as an 'afterburner system' for Nuclear Thermal Propulsion, other terrestrial applications can be thought of as well, making the system highly suited for a common space-terrestrial application research and utilisation strategy. (authors)
Interaction of biological systems with static and ELF electric and magnetic fields
Anderson, L.E.; Kelman, B.J.; Weigel, R.J. (eds.)
1987-01-01
Although background levels of atmospheric electric and geomagnetic field levels are extremely low, over the past several decades, human beings and other life forms on this planet have been subjected to a dramatically changing electromagnetic milieu. An exponential increase in exposure to electromagnetic fields has occurred, largely because of such technological advances as the growth of electrical power generation and transmission systems, the increased use of wireless communications, and the use of radar. In addition, electromagnetic field generating devices have proliferated in industrial plants, office buildings, homes, public transportation systems, and elsewhere. Although significant increases have occurred in electromagnetic field strenghths spanning all frequency ranges, this symposium addresses only the impact of these fields at static and extremely low frequencies (ELF), primarily 50 and 60 Hz. This volume contains the proceedings of the symposium entitled /open quotes/Interaction of biological systems with static and ELF electric and magnetic fields/close quotes/. The purpose of the symposium was to provide a forum for discussions of all aspects of research on the interaction of static and ELF electromagnetic fields with biological systems. These systems include simple biophysical models, cell and organ preparations, whole animals, and man. Dosimetry, exposure system design, and artifacts in ELF bioeffects research were also addressed, along with current investigations that examine fundamental mechanisms of interactions between the fields and biological processes. Papers are indexed separately.
Bibby, H.M. ); Dawson, G.B.; Rayner, H.H.; Bennie, S.L.; Bromley, C.J. )
1992-04-01
This paper reports that electrical and magnetic data are used in an investigation of a 450 km{sup 2} region in order to delineate the Rotorua City Geothermal system and determine its relationship with other geothermal systems in the region. Three distinct regions of low ({lt}30 Omega m) apparent resistivity are delineated. The southern of these outlines the Rotorua City Geothermal System which has an area of about 18 km{sup 2}, with the northern third covered by Lake Rotorua. The boundary of the system is characterized by a rapid lateral change in apparent resistivity which can be modeled as a single, near vertical zone in which the distance between hot and cold water is very narrow. Magnetic properties also change in the vicinity of the discontinuity in some areas, consistent with hydrothermal alteration having destroyed the magnetite in the rocks of the geothermal system. Hot water is believed to be rising, driven by buoyancy forces across the whole of the low resistivity region. There is some indication, particularly in the south, that the boundary between hot and cold fluids dips away from the field. A second low resistivity zone (the East Lake Rotorua anomaly) with an area of about 8 km{sup 2}, is believed to outline a second independent geothermal system, with surface manifestations on Mokoia Island, and on the eastern shore of the lake. High heat flow in lake bottom sediments, and a reduction in magnetic signature over this region supports this conclusion. A third resistivity low under the west of Lake Rotorua has no associated thermal features and is believed to be a fossil hydrothermal system. There is no apparent relationship between the location of the geothermal systems and the Rotorua caldera. The aeromagnetic measurements have delineated several highly magnetic bodies which cannot be linked with surface geology. These are believed to be caused by buried rhyolite dome complexes at shallow depth.
Vector Magnetic Fields and Electric Currents from the Imaging Vector Magnetograph
Jing Li; A. A. van Ballegooijen; Don Mickey
2008-11-01
First, we describe a general procedure to produce high quality vector magnetograms using the Imaging Vector Magnetograph (IVM) at Mees Solar Observatory. At the spatial resolution 2"x2", the Stokes Q,U,V uncertainty reaches 0.001-0.0005 in time-averaged data over 1-hour in the quiet Sun. When vector magnetic fields are inferred from the time-averaged Stokes spectral images of FeI 6302.5A, the resulting uncertainties are on the order of 10 G for the longitudinal fields, 40 G for the transverse field strength and 9 degree for the magnetic azimuth. The magnetic field inversion used in this work is the "Triplet" code, which was developed and implemented in the IVM software package by the late Barry J. LaBonte. The inversion code is described in detail in the Appendix. Second, we solve for the absolute value of the vertical electric current density, |Jz|, accounting for the above IVM problems, for two different active regions. One is a single sunspot region (NOAA 10001 observed on 20 June 2002) while the other is a more complex, quadrupolar region (NOAA10030 observed on 15 July 2002). We use a calculation that does not require disambiguation of 180 degree in the transverse field directions. The |Jz| uncertainty is on the order of 7.0 mA m^-2. The vertical current density increases with increasing vertical magnetic field. The rate of increase is about 1 -2 times as large in the quadrupolar NOAA 10030 region as in the simple NOAA 10001, and it is more spatially variable over NOAA 10030 than over NOAA 10001.
Measurement of the proton electric to magnetic form factor ratio from \\vec ^1H(\\vec e, e'p)
C. B. Crawford; A. Sindile; T. Akdogan; R. Alarcon; W. Bertozzi; E. Booth; T. Botto; J. Calarco; B. Clasie; A. DeGrush; T. W. Donnelly; K. Dow; D. Dutta; M. Farkhondeh; R. Fatemi; O. Filoti; W. Franklin; H. Gao; E. Geis; S. Gilad; W. Haeberli; D. Hasell; W. Hersman; M. Holtrop; P. Karpius; M. Kohl; H. Kolster; T. Lee; A. Maschinot; J. Matthews; K. McIlhany; N. Meitanis; R. G. Milner; J. Rapaport; R. P. Redwine; J. Seely; A. Shinozaki; S. Sirca; E. Six; T. Smith; B. Tonguc; C. Tschalaer; E. Tsentalovich; W. Turchinetz; J. F. J. van den Brand; J. van der Laan; F. Wang; T. Wise; Y. Xiao; W. Xu; C. Zhang; Z. Zhou; V. Ziskin; T. Zwart
2006-09-07
We report the first precision measurement of the proton electric to magnetic form factor ratio from spin-dependent elastic scattering of longitudinally polarized electrons from a polarized hydrogen internal gas target. The measurement was performed at the MIT-Bates South Hall Ring over a range of four-momentum transfer squared $Q^2$ from 0.15 to 0.65 (GeV/c)$^2$. Significantly improved results on the proton electric and magnetic form factors are obtained in combination with previous cross-section data on elastic electron-proton scattering in the same $Q^2$ region.
B. Plaster
2013-09-22
We propose a new concept for determining the interior magnetic field vector components in neutron electric dipole moment experiments. If a closed three-dimensional boundary surface surrounding the fiducial volume of an experiment can be defined such that its interior encloses no currents or sources of magnetization, each of the interior vector field components and the magnetic scalar potential will satisfy a Laplace equation. Therefore, if either the vector field components or the normal derivative of the scalar potential can be measured on the surface of this boundary, thus defining a Dirichlet or Neumann boundary-value problem, respectively, the interior vector field components or the scalar potential (and, thus, the field components via the gradient of the potential) can be uniquely determined via solution of the Laplace equation. We discuss the applicability of this technique to the determination of the interior magnetic field components during the operating phase of neutron electric dipole moment experiments when it is not, in general, feasible to perform direct in situ measurements of the interior field components. We also study the specifications that a vector field probe must satisfy in order to determine the interior vector field components to a certain precision. The technique we propose here may also be applicable to experiments requiring monitoring of the vector magnetic field components within some closed boundary surface, such as searches for neutron-antineutron oscillations along a flight path or measurements in storage rings of the muon anomalous magnetic moment $g-2$ and the proton electric dipole moment.
V. G. Baryshevsky
2005-10-12
In the present paper influence of tensor electric and magnetic polarizabilities on spin evolution in the resonance deuteron EDM experiment is considered in details. It is shown that besides EDM the electric and magnetic polarizabilities also contribute to the vertical spin component P_3. Moreover, the electric polarizability contributes to the P_3 component even when the deuteron EDM is supposed to be zero and thereby the electric polarizability can imitate the EDM contribution. It is shown that unlike the vertical component of the spin P_3 the component P_{33} of polarization tensor does not contain contribution from the electric polarizability, whereas contribution from the magnetic polarizability reveals only when the deuteron EDM differs from zero. Moreover, it is also shown that when the angle $\\vartheta$ between the spin direction and the vertical axis meets the condition $\\sin \\vartheta=\\sqrt{{2/3}}$ ($\\cos \\vartheta=\\sqrt{{1/3}}$), the initial value of $P_{33}$ appears $P_{33}(0)=0$. As a result, EDM contribution to the measured signal linearly growth in time starting from zero that is important for measurements. Therefore, measurement of the P_{33} component of deuteron tensor polarization seems to be of particular interest, especially because the nonzero component P_{33} appearance on its own indicates the EDM presence (in contrast to the P_3 component, which appearance can be aroused by the tensor electric polarizability, rather than EDM).
8.02 Electricity and Magnetism: TEAL:Studio Physics Project, Fall 2002
Belcher, John W.
Introduction to electromagnetism and electrostatics: electric charge, Coulomb's law, electric structure of matter; conductors and dielectrics. Concepts of electrostatic field and potential, electrostatic energy. Electric ...
Marin, S
2015-01-01
The stereochemical properties of the ultracold ground state OH molecule in the presence of electric and magnetic fields are currently of considerable interest. For example, relevant quantities such as molecular alignment and orientation, calculated numerically by using large basis sets, have lately appeared in the literature. In this work, based on our recent exact solution to an effective eight-dimensional matrix Hamiltonian for the molecular ground state, we present analytic expressions for the stereochemical properties of OH. Our results require the solution of algebraic equations only, agree well with the aforementioned fully numerical calculations, provide compact expressions for simple field geometries, allow ready access to relatively unexplored parameter space, and yield straightforwardly higher moments of the molecular axis distribution.
Metodiev, E M; Fandaros, M; Haciomeroglu, S; Huang, D; Huang, K L; Patil, A; Prodromou, R; Semertzidis, O A; Sharma, D; Stamatakis, A N; Orlov, Y F; Semertzidis, Y K
2015-01-01
A set of analytical benchmarks for tracking programs are required for precision storage ring experiments. To determine the accuracy of precision tracking programs in electric and magnetic rings, a variety of analytical estimates of particle and spin dynamics in the rings are developed and compared to the numerical results of tracking simulations. Initial discrepancies in the comparisons indicated the need for improvement of several of the analytical estimates. As an example, we find that the fourth order Runge-Kutta/Predictor-Corrector method was accurate but slow, and that it passed all the benchmarks it was tested against, often to the sub-part per billion level. Thus high precision analytical estimates and tracking programs based on fourth order Runge-Kutta/Predictor-Corrector integration can be used to benchmark faster tracking programs for accuracy.
Analytical Benchmarks for Precision Particle Tracking in Electric and Magnetic Rings
E. M. Metodiev; I. M. D'Silva; M. Fandaros; M. Gaisser; S. Haciomeroglu; D. Huang; K. L. Huang; A. Patil; R. Prodromou; O. A. Semertzidis; D. Sharma; A. N. Stamatakis; Y. F. Orlov; Y. K. Semertzidis
2015-05-17
A set of analytical benchmarks for tracking programs is required for precision storage ring experiments. To determine the accuracy of precision tracking programs in electric and magnetic rings, a variety of analytical estimates of particle and spin dynamics in the rings were developed and compared to the numerical results of tracking simulations. Initial discrepancies in the comparisons indicated the need for improvement of several of the analytical estimates. As an example, we found that the fourth-order Runge-Kutta/Predictor-Corrector method was slow but accurate, and that it passed all the benchmarks it was tested against, often to the sub-part per billion level. Thus, high precision analytical estimates and tracking programs based on fourth-order Runge-Kutta/Predictor-Corrector integration can be used to benchmark faster tracking programs for accuracy.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jain, Aditya; Moitra, Parikshit; Koschny, Thomas; Valentine, Jason; Soukoulis, Costas M.
2015-07-14
Artificially created surfaces or metasurfaces, composed of appropriately shaped subwavelength structures, namely, meta-atoms, control light at subwavelength scales. Historically, metasurfaces have used radiating metallic resonators as subwavelength inclusions. However, while resonant optical metasurfaces made from metal have been sufficiently subwavelength in the propagation direction, they are too lossy for many applications. Metasurfaces made out of radiating dielectric resonators have been proposed to solve the loss problem, but are marginally subwavelength at optical frequencies. We designed subwavelength resonators made out of nonradiating dielectrics. The resonators are decorated with appropriately placed scatterers, resulting in a meta-atom with an engineered electromagnetic response. Amore »metasurface that yields an electric response is fabricated, experimentally characterized, and a method to obtain a magnetic response at optical frequencies is theoretically demonstrated. This design methodology paves the way for metasurfaces that are simultaneously subwavelength and low loss.« less
Lasche, George P. (Arlington, VA)
1988-01-01
A high-power-density laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems.
Lasche, G.P.
1983-09-29
The invention is a laser or particle-beam-driven fusion reactor system which takes maximum advantage of both the very short pulsed nature of the energy release of inertial confinement fusion (ICF) and the very small volumes within which the thermonuclear burn takes place. The pulsed nature of ICF permits dynamic direct energy conversion schemes such as magnetohydrodynamic (MHD) generation and magnetic flux compression; the small volumes permit very compact blanket geometries. By fully exploiting these characteristics of ICF, it is possible to design a fusion reactor with exceptionally high power density, high net electric efficiency, and low neutron-induced radioactivity. The invention includes a compact blanket design and method and apparatus for obtaining energy utilizing the compact blanket.
Lasche, G.P.
1987-02-20
A high-power-density-laser or charged-particle-beam fusion reactor system maximizes the directed kinetic energy imparted to a large mass of liquid lithium by a centrally located fusion target. A fusion target is embedded in a large mass of lithium, of sufficient radius to act as a tritium breeding blanket, and provided with ports for the access of beam energy to implode the target. The directed kinetic energy is converted directly to electricity with high efficiency by work done against a pulsed magnetic field applied exterior to the lithium. Because the system maximizes the blanket thickness per unit volume of lithium, neutron-induced radioactivities in the reaction chamber wall are several orders of magnitude less than is typical of other fusion reactor systems. 25 figs.
Biological interactions of extremely-low-frequency electric and magnetic fields
Tenforde, T.S.
1990-03-01
A description is given of the fundamental physical properties of extremely-low frequency (ELF) electromagnetic fields, and the mechanisms through which these fields interact with the human body at a macroscopic level. the mechanisms through which ELF electric and magnetic fields induce currents in humans and other living objects are described. Evidence is presented that cell membranes play an important role in transducing ELF signals. Both experimental evidence and theoretical models are described that relate pericellular currents and electrochemical events at the outer membrane surface to transmembrane signaling pathways and cytoplasmic responses. Biological responses to ELF fields at the tissue, cellular and molecular levels are summarized, including new evidence that ELF field exposure produces alterations in messenger RNA synthesis, gene expression and the cytoplasmic concentrations of specific proteins. 50 refs., 9 figs., 2 tabs.
Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor
Scott, T.C.
1990-07-17
Methods and systems are disclosed for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a packing'' are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets. 2 figs.
Electric field-driven, magnetically-stabilized ferro-emulsion phase contactor
Scott, Timothy C. (Knoxville, TN)
1990-01-01
Methods and systems for interfacial surface area contact between a dispersed phase liquid and a continuous phase liquid in counter-current flow for purposes such as solvent extraction. Initial droplets of a dispersed phase liquid material containing ferromagnetic particles functioning as a "packing" are introduced to a counter-current flow of the continuous phase. A high intensity pulsed electric field is applied so as to shatter the initial droplets into a ferromagnetic emulsion comprising many smaller daughter droplets having a greater combined total surface area than that of the initial droplets in contact with the continuous phase material. A magnetic field is applied to control the position of the ferromagnetic emulsion for enhanced coalescence of the daughter droplets into larger reformed droplets.
Thin film deposition by electric and magnetic crossed-field diode sputtering
Welch, Kimo M. (Mountain View, CA)
1980-01-01
Applying a thin film coating to the surface of a workpiece, in particular, applying a coating of titanium nitride to a klystron window by means of a crossed-field diode sputtering array. The array is comprised of a cohesive group of numerous small hollow electrically conducting cylinders and is mounted so that the open ends of the cylinders on one side of the group are adjacent a titanium cathode plate. The workpiece is mounted so as to face the open ends of the other side of the group. A magnetic field is applied to the array so as to be coaxial with the cylinders and a potential is applied across the cylinders and the cathode plate, the cylinders as an anode being positive with respect to the cathode plate. The cylinders, the cathode plate and the workpiece are situated in an atmosphere of nitrogen which becomes ionized such as by field emission because of the electric field between the cylinders and cathode plate, thereby establishing an anode-cathode discharge that results in sputtering of the titanium plate. The sputtered titanium coats the workpiece and chemically combines with the nitrogen to form a titanium nitride coating on the workpiece. Gas pressure, gas mixtures, cathode material composition, voltages applied to the cathode and anode, the magnetic field, cathode, anode and workpiece spacing, and the aspect ratio (ratio of length to inner diameter) of the anode cylinders, all may be controlled to provide consistent optimum thin film coatings of various compositions and thicknesses. Another facet of the disclosure is the coating of microwave components per se with titanium nitride to reduce multipactoring under operating conditions of the components.
Komorowski, P A
2000-01-01
The localization of possible electrical faults in superconducting accelerator magnets may, in most cases, be a complex, expensive and time-consuming process. In particular, inter-turn short circuits and failures of the ground insulation are well detectable when the magnet is collared, but often disappear after disassembly for repair due to the release of the pre-stress in the coils. The fault localization method presented in this paper is based on the measurement and analysis of the magnetic field generated inside the magnet aperture by a high voltage pulse. The presence of the fault modifies the distribution of the current in the coils and produces a distortion of the magnetic field. The described method aims at locating both the longitudinal and azimuthal position of the fault-affected area. The test method, the transient case FEM models and the implemented experimental set-up are presented and discussed for the LHC dipole models.
Generalized Uhlenbeck-Goudsmit hypothesis 'Magnetic' S^{a} and 'Electric' Z^{a} Spins
Tomislav Ivezic
2010-03-23
In this paper, the connection between the dipole moment tensor D^{ab} and the spin four-tensor S^{ab} is formulated in the form of the generalized Uhlenbeck-Goudsmit hypothesis, D^{ab}=g_{S}S^{ab}. It is also found that the spin four-tensor S^{ab} can be decomposed into two 4-vectors, the usual `space-space' intrinsic angular momentum S^{a}, which will be called `magnetic' spin (mspin), and a new one, the `time-space' intrinsic angular momentum Z^{a}, which will be called `electric' spin (espin). Both spins are equally good physical quantities. Taking into account the generalized Uhlenbeck-Goudsmit hypothesis, the decomposition of S^{ab} and the decomposition of D^{ab} into the dipole moments m^{a} and d^{a}, we find that an electric dipole moment (EDM) of a fundamental particle, as a four-dimensional (4D) geometric quantity, is determined by Z^{a} and not, as generally accepted, by the spin $\\mathbf{S}$ as a 3-vector. Also it is shown that neither the T inversion nor the P inversion are good symmetries in the 4D spacetime. In this geometric approach, only the world parity W, Wx^{a}=-x^{a}, is well defined in the 4D spacetime. Some consequences for elementary particle theories and experiments that search for EDM are briefly discussed.
Electrically detected magnetic resonance modeling and fitting: An equivalent circuit approach
Leite, D. M. G.; Batagin-Neto, A.; Nunes-Neto, O.; Gómez, J. A.; Graeff, C. F. O.
2014-01-21
The physics of electrically detected magnetic resonance (EDMR) quadrature spectra is investigated. An equivalent circuit model is proposed in order to retrieve crucial information in a variety of different situations. This model allows the discrimination and determination of spectroscopic parameters associated to distinct resonant spin lines responsible for the total signal. The model considers not just the electrical response of the sample but also features of the measuring circuit and their influence on the resulting spectral lines. As a consequence, from our model, it is possible to separate different regimes, which depend basically on the modulation frequency and the RC constant of the circuit. In what is called the high frequency regime, it is shown that the sign of the signal can be determined. Recent EDMR spectra from Alq{sub 3} based organic light emitting diodes, as well as from a-Si:H reported in the literature, were successfully fitted by the model. Accurate values of g-factor and linewidth of the resonant lines were obtained.
Pressure-dependent magnetism and electrical resistivity of UFe/sub 4/P/sub 12/
Guertin, R.P.; Rossel, C.; Torikachvili, M.S.; McElfresh, M.W.; Maple, M.B.; Bloom, S.H.; Yao, Y.S.; Kuric, M.V.; Meisner, G.P.
1987-12-01
UFe/sub 4/P/sub 12/ is the first reported uranium-based ferromagnetic semiconductor. The Curie temperature T/sub C/ is 3.15 K, and the spontaneous magnetic moment sigma/sub 0/ which at T = 1.14 K was found to be approx. =1.0 ..mu../sub B//(U atom), is associated entirely with the uranium ions. The electrical resistivity rho(T) increases by nearly 7 orders of magnitude as temperature is decreased from room temperature to 4.2 K. The behavior of the ferromagnetic and electrical properties of UFe/sub 4/P/sub 12/ in hydrostatic pressures up to 16 kbar is reported. Quasihydrostatic-pressure effects on rho(T) to 100 kbar are also reported. Although T/sub C/ increases sharply with increasing pressure at the rate dT/sub C//dP = 0.26 K/kbar (in contrast to similar data on the isomorphic ferromagnet NdFe/sub 4/P/sub 12/, where dT/sub C//dP = 0.03 K/kbar), sigma/sub 0/ decreases, (1/sigma/sub 0/)(dsigma/sub 0//dp) = -0.007 kbar/sup -1/. Hydrostatic and quasihydrostatic pressure have little effect on rho(T).
S. J. van Enk
2013-03-25
The concept of electric and magnetic field lines is intrinsically non-relativistic. Nonetheless, for certain types of fields satisfying certain geometric properties, field lines can be defined covariantly. More precisely, two Lorentz-invariant 2D surfaces in spacetime can be defined such that magnetic and electric field lines are determined, for any observer, by the intersection of those surfaces with spacelike hyperplanes. An instance of this type of field is constituted by the so-called Hopf-Ranada solutions of the source-free Maxwell equations, which have been studied because of their interesting topological properties, namely, linkage of their field lines. In order to describe both geometric and topological properties in a succinct manner, we employ the tools of Geometric Algebra (aka Clifford Algebra) and use the Clebsch representation for the vector potential as well as the Euler representation for both magnetic and electric fields. This description is easily made covariant, thus allowing us to define electric and magnetic field lines covariantly in a compact geometric language. The definitions of field lines can be phrased in terms of 2D surfaces in space. We display those surfaces in different reference frames, showing how those surfaces change under Lorentz transformations while keeping their topological properties. As a byproduct we also obtain relations between optical helicity, optical chirality and generalizations thereof, and their conservation laws.
A. J. Silenko
2006-02-03
The Hamiltonian of relativistic particles with electric and magnetic dipole moments that interact with an electromagnetic field is determined in the Foldy-Wouthuysen representation. Transition to the semiclassical approximation is carried out. The quantum-mechanical and semiclassical equations of spin motion are derived.
Not Available
1990-05-01
This report is a collection of papers documenting presentations made at the VIII ASA (American Statistical Association) Conference on Radiation and Health entitled Health Effects of Electric and Magnetic Fields: Statistical Support for Research Strategies. Individual papers are abstracted and indexed for the database.
Papitashvili, V.O. [Institute of Terrestrial Magnetism, Moscow (Russian Federation)]|[Univ. of Michigan, Ann Arbor, MI (United States); Belov, B.A.; Faermark, D.S.; Feldstein, Ya.I.; Golyshev, S.A.; Gromova, L.I.; Levitin, A.E. [Institute of Terrestrial Magnetism, Moscow (Russian Federation)
1994-07-01
Electric potential patterns have been obtained from the IZMIRAN electrodynamic model (IZMEM) for the northern and southern polar regions during summer, winter, and equinox. The model is derived from a large quantity of high-latitude ground-based geomagnetic data (above {+-} 57{degrees} corrected geomagnetic latitude) at all magnetic local time hours. A linear regression analysis technique has been used to obtain the quantitative response of each magnetic observatory to changes of interplanetary magnetic field (IMF) components. Since no ionospheric conductivity model exists specifically for the southern polar region, the statistical model of Wallis and Budzinski has been applied in both hemispheres. A cross-polar `background` potential of {approximately} 35 kV, derived by Reiff et al., is used to calibrate IZMEM`s potential patterns. The model`s response to changes in the IMF B{sub y} and B{sub z} components are analyzed to obtain a set of {open_quotes}elementary{close_quotes} convection patterns in both polar regions for each season of the year. Asymmetry in the potential pattern geometry in both hemispheres can be attributed either to the influence of the {open_quotes}northern{close_quotes} ionospheric conductivity model which was applied to the southern polar region, or to some natural phenomena. Average values of the modeled potential drop caused by each nanotesla of the IMF are the following: {approximately} 14 kV for southward B{sub z}; {approximately} {minus}4 kV for northward B{sub z}; and {approximately} {+-} 4.5 kV for B{sub y} components. The latter is not applicable to the {open_quotes}dawn-dusk{close_quotes} potential drop; it may be applied across the cusp region only. It is concluded that IZMEM provides realistic convection patterns parameterized by the IMF component directions and magnitudes and may be used to provide routine estimates of convection patterns and electric potentials if IMF data are available. 43 refs., 7 figs., 1 tab.
M. A. Pooley; A. J. Bennett; R. M. Stevenson; A. J. Shields; I. Farrer; D. A. Ritchie
2015-07-28
The neutral biexciton cascade of single quantum dots is a promising source of entangled photon pairs. The character of the entangled state is determined by the energy difference between the excitonic eigenstates known as fine-structure splitting (FSS). Here we reduce the magnitude of the FSS by simultaneously using two independent tuning mechanisms: in-plane magnetic field and vertical electric field. We observe that there exists a minimum possible FSS in each quantum dot which is independent of these tuning mechanisms. However, with simultaneous application of electric and magnetic fields, we show the FSS can be reduced to its minimum value as the energy of emission is tuned over several meV with a 5-T magnet.
T. M. Aliev; K. Azizi; M. Savci
2009-10-11
The electric quadrupole and magnetic octupole moments of the light decuplet baryons are calculated in the framework of the light cone QCD sum rules. The obtained non-vanishing values for the electric quadrupole and magnetic octupole moments of these baryons show nonspherical charge distribution. The sign of electric quadrupole moment is positive for $\\Omega^-$, $\\Xi^{*-}$, $\\Sigma^{*-}$ and negative for $\\Sigma^{*+}$, which correspond to the prolate and oblate charge distributions, respectively. A comparison of the obtained results with the predictions of non-covariant quark model which shows a good consistency between two approaches is also presented. Comparison of the obtained results on the multipole moments of the decuplet baryons containing strange quark with those of $\\Delta$ baryons shows a large SU(3) flavor symmetry breaking.
Otaduy, P.J.; Hsu, J.S.; Adams, D.J.
2007-11-30
This report describes research performed on the viability of changing the effectively active number of turns in the stator windings of an internal permanent magnet (IPM) electric motor to strengthen or weaken the magnetic fields in order to optimize the motor's performance at specific operating speeds and loads. Analytical and simulation studies have been complemented with research on switching mechanisms to accomplish the task. The simulation studies conducted examine the power and energy demands on a vehicle following a series of standard driving cycles and the impact on the efficiency and battery size of an electrically propelled vehicle when it uses an IPM motor with turn-switching capabilities. Both full driving cycle electric propulsion and propulsion limited starting from zero to a set speed have been investigated.
Kim, C.H.
1987-04-01
This report compares two physics designs of the low energy end of an induction linac-ICF driver: one using electric quadrupole focusing of many parallel beams followed by transverse combining; the other using magnetic quadrupole focusing of fewer beams without beam combining. Because of larger head-to-tail velocity spread and a consequent rapid current amplification in a magnetic focusing channel, the overall accelerator size of the design using magnetic focusing is comparable to that using electric focusing.
Electrical Performance of a String of Magnets Representing a Half-cell of the LHC Machine
Rodriguez-Mateos, F.
2011-01-01
at Magnet Technology (MT-14), Tampere, Finland, June 11-16,at Magnet Technology (MT-14), Tampere, Finland, June 11- 16,
L. Neslusan
2010-12-28
Considering two static, electrically charged, elementary particles, we demonstrate a possible way of proving that all known fundamental forces in the nature are the manifestations of the single, unique interaction. We re-define the gauging of integration constants in the Schwarzschild solution of Einstein field equations. We consider the potential energy in this context regardless it is gravitational or electric potential energy. With the newly gauged constants, we sketch how the unique interaction can be described with the help of an appropriate solution of the well-known Maxwell equations. According the solution, there are two zones, in the system of two oppositely charged particles, where the force is oscillating. The first particle can be in a stable, constant distance from the second particle, between the neighbouring regions of repulsion and attraction. In an outer oscillation zone, the corresponding energy levels in the proton-electron systems are identical (on the level of accuracy of values calculated by the Dirac's equations) to some experimentally determined levels in the hydrogen atom. For each system of two particles, there is also the zone with the macroscopic, i.e. monotonous behavior of the force. As well, the solution can be used to demonstrate that the net force between two assemblies consisting each (or at least one) of the same numbers of both positively and negatively charged particles is never zero. A secondary electric force, having the same orientation as the primary electric force between the oppositely charged particles, is always present. It can be identified to the gravity. Finally, the solution of the Maxwell equations can be used to calculate the inertia force of a particle. The consistent formulas for both acting and inertia forces enable to construct the dimensionless (without gravitational constant, permitivity of vacuum, etc.) equation of motion.
GAS COOLED ELECTRICAL LEADS FOR USE ON FORCED COOLED SUPERCONDUCTING MAGNETS
Smits, R.G.
2010-01-01
11-14, 1981 GAS COOLED ELECTRICAL LEADS FOR USE ON FORCEDim mumii P mm GAS COOLED ELECTRICAL LEADS FOR USE ON FORCEDD. Henning, "Cryogenic Electrical Leads," Proceedings of the
Coïsson, R
2015-01-01
The interaction between point charge and magnetic dipole is usually considered only for the case of a rigid ferromagnetic dipole (constant-current): here the analysis of force, momentum and energy (including the energy provided by the internal current generator) is generalised to any magnetic dipole behaviour: rigid, paramagnetic, diamagnetic or superconducting (perfectly diamagnetic).
General Electric-Magnetic decomposition of fields, positivity and Rainich-like conditions
Jose M M Senovilla
2000-10-29
We show how to generalize the classical electric-magnetic decomposition of the Maxwell or the Weyl tensors to arbitrary fields described by tensors of any rank in general $n$-dimensional spacetimes of Lorentzian signature. The properties and applications of this decomposition are reviewed. In particular, the definition of tensors quadratic in the original fields and with important positivity properties is given. These tensors are usually called "super-energy" (s-e) tensors, they include the traditional energy-momentum, Bel and Bel-Robinson tensors, and satisfy the so-called Dominant Property, which is a straightforward generalization of the classical dominant energy condition satisfied by well-behaved energy-momentum tensors. We prove that, in fact, any tensor satisfying the dominant property can be decomposed as a finite sum of the s-e tensors. Some remarks about the conservation laws derivable from s-e tensors, with some explicit examples, are presented. Finally, we will show how our results can be used to provide adequate generalizations of the Rainich conditions in general dimension and for any physical field.
Lorentz Transformations of the Electric and Magnetic Fields According to Minkowski
Tomislav Ivezic
2010-03-06
The usual transformations (UT) of the 3-vectors E and B that are found by Lorentz, Poincar\\'{e} and independently by Einstein in 1905. are generally considered to be the Lorentz transformations (LT) of E and B. According to the UT E in one frame is 'seen' as E' and B' in a relatively moving frame. In Minkowski's last paper, in 1908. in section 11.6, he defined the vectors (with four components) of the electric $\\Phi $ and magnetic $\\Psi $ fields and discovered that, e.g., $\\Phi $ correctly transforms by the LT again to $\\Phi ^{\\prime}$. His correct LT are reinvented in, e.g., [11] ([11] Ivezi\\'{c} T 2005 Found. Phys. Lett. 18 301). In this paper we show the essential similarity and some differences between Minkowski's relations in section 11.6 and the results obtained in [11]. The low-velocity limit of the UT and the LT is briefly examined. A short discussion of the comparison with the Trouton-Noble experiment is presented.
NONE
1997-06-01
The Electric and Magnetic Fields (EMF) Research and Public Information Dissemination (RAPID) Program was authorized by the Energy Policy Act of 1992 as a near-term effort to expand and accelerate the research needed to address the EMF issue. As required by this legislation, the EMF Interagency Committee, the National EMF Advisory Committee (NEMFAC), and the National Academy of Sciences (NAS) are providing valued input and advice for the direction of this program. With this input and advice, the Department of Energy (DOE) and the National Institute of Environmental Health Sciences (NIEHS) have developed and are implementing five-year program plans. Multi-year health effects research projects and related EMF measurement and exposure assessment projects are underway using funds appropriated in fiscal years 1994, 1995, and 1996 together with voluntary non-Federal contributions. The results of these research projects, along with the results of other EMF research, will be used as input to the hazard evaluation effort, which is the focus of the EMF RAPID Program. A coordinated interagency program is underway to communicate needed information on the EMF issue in a clear manner to the public and other decision makers.
Saskia Grunau; Valeria Kagramanova
2010-11-24
We present the full set of analytical solutions of the geodesic equations of charged test particles in the Reissner-Nordstr\\"om space-time in terms of the Weierstra{\\ss} $\\wp$, $\\sigma$ and $\\zeta$ elliptic functions. Based on the study of the polynomials in the $\\vartheta$ and $r$ equations we characterize the motion of test particles and discuss their properties. The motion of charged test particles in the Reissner-Nordstr\\"om space-time is compared with the motion of neutral test particles in the field of a gravitomagnetic monopole. Electrically or magnetically charged particles in the Reissner-Nordstr\\"om space-time with magnetic or electric charges, respectively, move on cones similar to neutral test particles in the Taub-NUT space-times.
Stephan Gekle; Jörg Main; Thomas Bartsch; T. Uzer
2006-10-02
A hierarchical ordering is demonstrated for the periodic orbits in a strongly coupled multidimensional Hamiltonian system, namely the hydrogen atom in crossed electric and magnetic fields. It mirrors the hierarchy of broken resonant tori and thereby allows one to characterize the periodic orbits by a set of winding numbers. With this knowledge, we construct the action variables as functions of the frequency ratios and carry out a semiclassical torus quantization. The semiclassical energy levels thus obtained agree well with exact quantum calculations.
Structural, magnetic and electrical properties of the hexagonal ferrites MFeO{sub 3} (M=Y, Yb, In)
Downie, Lewis J.; Goff, Richard J.; Kockelmann, Winfried; Forder, Sue D.; Parker, Julia E.; Morrison, Finlay D.; Lightfoot, Philip
2012-06-15
The hexagonal ferrites MFeO{sub 3} (M=Y, Yb, In) have been studied using a combination of neutron and X-ray powder diffraction, magnetic susceptibility, dielectric measurements and {sup 57}Fe Moessbauer spectroscopy. This study confirms the previously reported crystal structure of InFeO{sub 3} (YAlO{sub 3} structure type, space group P6{sub 3}/mmc), but YFeO{sub 3} and YbFeO{sub 3} both show a lowering of symmetry to at most P6{sub 3}cm (ferrielectric YMnO{sub 3} structure type). However, Moessbauer spectroscopy shows at least two distinct Fe sites for both YFeO{sub 3} and YbFeO{sub 3} and we suggest that the best model to rationalise this involves phase separation into more than one similar hexagonal YMnO{sub 3}-like phase. Rietveld analysis of the neutron diffraction data was carried out using two hexagonal phases as a simplest case scenario. In both YFeO{sub 3} and YbFeO{sub 3}, distinct dielectric anomalies are observed near 130 K and 150 K, respectively. These are tentatively correlated with weak anomalies in magnetic susceptibility and lattice parameters, for YFeO{sub 3} and YbFeO{sub 3}, respectively, which may suggest a weak magnetoelectric effect. Comparison of neutron and X-ray powder diffraction shows evidence of long-range magnetic order in both YFeO{sub 3} and YbFeO{sub 3} at low temperatures. Due to poor sample crystallinity, the compositional and structural effects underlying the phase separation and possible magnetoelectric phenomena cannot be ascertained. - Graphical abstract: Hexagonal MFeO{sub 3} (M=Y, Yb) exhibit phase separation into two YMnO{sub 3}-like phases. Variable temperature crystallographic, electrical and magnetic studies suggest weak correlations between electrical and magnetic responses and long-range magnetic order at low temperature. Highlights: Black-Right-Pointing-Pointer Multi-technique study of multiferroic hexagonal MFeO{sub 3}. Black-Right-Pointing-Pointer Phase separation into two similar hexagonal phases. Black-Right-Pointing-Pointer Weak coupling of electrical and magnetic responses. Black-Right-Pointing-Pointer Long-range magnetic order at low T.
Muon anomalous magnetic moment in a $SU(4) \\otimes U(1)_N$ model without exotic electric charges
D. Cogollo
2014-11-11
We study an electroweak gauge extension of the standard model, so called 3-4-1 model, which does not contain exotic electric charges and it is anomaly free. We discuss phenomenological constraints of the model and compute all the corrections to the muon magnetic moment. Mainly, we discuss different mass regimes and their impact on this correction, deriving for the first time direct limits on the masses of the neutral fermions and charged vector bosons. Interestingly, the model could address the reported muon anomalous magnetic moment excess, however it would demands a rather low scale of symmetry breaking, far below the current electroweak constraints on the model. Thus, if this excess is confirmed in the foreseeable future by the g-2 experiment at FERMILAB, this 3-4-1 model can be decisively ruled out since the model cannot reproduce a sizeable and positive contribution to the muon anomalous magnetic moment consistent with current electroweak limits.
Chen Lijen; Lefebvre, Bertrand; Torbert, Roy B.; Daughton, William S.
2011-01-15
Based on two-dimensional fully kinetic simulations that resolve the electron diffusion layer in undriven collisionless magnetic reconnection with zero guide field, this paper reports the existence and evolution of an inversion layer of bipolar electric fields, its corresponding phase-space structure (an electron-hole layer), and the implication to collisionless dissipation. The inversion electric field layer is embedded in the layer of bipolar Hall electric field and extends throughout the entire length of the electron diffusion layer. The electron phase-space hole structure spontaneously arises during the explosive growth phase when there exist significant inflows into the reconnection layer, and electrons perform meandering orbits across the layer while being cyclotron-turned toward the outflow directions. The cyclotron turning of meandering electrons by the magnetic field normal to the reconnection layer is shown to be a primary factor limiting the current density in the region where the reconnection electric field is balanced by the gradient (along the current sheet normal) of the off-diagonal electron pressure-tensor.
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you nay give us will be greatly uppreckted. VPry truly your23, 9. IX. Sin0j3, Mtinager lclectronics and Nuclear Physics Dept. omh , WESTINGHOUSE-THE NAT KING IN ELECTRICITY...
Entanglement Entropy of Magnetic Electron Stars
Tameem Albash; Clifford V. Johnson; Scott MacDonald
2015-04-08
We study the behavior of the entanglement entropy in $(2+1)$--dimensional strongly coupled theories via the AdS/CFT correspondence. We consider theories at a finite charge density with a magnetic field, with their holographic dual being Einstein-Maxwell-Dilaton theory in four dimensional anti--de Sitter gravity. Restricting to black hole and electron star solutions at zero temperature in the presence of a background magnetic field, we compute their holographic entanglement entropy using the Ryu-Takayanagi prescription for both strip and disk geometries. In the case of the electric or magnetic zero temperature black holes, we are able to confirm that the entanglement entropy is invariant under electric-magnetic duality. In the case of the electron star with a finite magnetic field, for the strip geometry, we find a discontinuity in the first derivative of the entanglement entropy as the strip width is increased.
Brodsky, Stanley J.; /SLAC; Gardner, Susan; /Kentucky U.; Hwang, Dae Sung; /Sejong U.
2006-01-11
We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n} {approx} -{kappa}{sup p}.
Brodsky, Stanley J. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States); Gardner, Susan [Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055 (United States); Hwang, Dae Sung [Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of)
2006-02-01
We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n}{approx}-{kappa}{sup p}.
S. J. Brodsky; S. Gardner; D. S. Hwang
2006-02-27
We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, kappa^n ~ - kappa^p.
Self-propulsion of a spherical electric or magnetic microbot in a polar viscous fluid
Felderhof, B U
2014-01-01
The self-propulsion of a sphere immersed in a polar liquid or ferrofluid is studied on the basis of ferrohydrodynamics. In the electrical case an oscillating charge density located inside the sphere generates an electrical field which polarizes the fluid. The lag of polarization with respect to the electrical field due to relaxation generates a time-independent electrical torque density acting on the fluid causing it to move. The resulting propulsion velocity of the sphere is calculated in perturbation theory to second order in powers of the charge density.
Yannis Burnier; Dmitri E. Kharzeev; Jinfeng Liao; Ho-Ung Yee
2011-03-07
Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon plasma in the presence of external magnetic field that stems from the interplay of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by the waves of the electric and chiral charge densities coupled by the axial anomaly. We consider CMW at finite baryon density and find that it induces the electric quadrupole moment of the quark-gluon plasma produced in heavy ion collisions: the "poles" of the produced fireball (pointing outside of the reaction plane) acquire additional positive electric charge, and the "equator" acquires additional negative charge. We point out that this electric quadrupole deformation lifts the degeneracy between the elliptic flows of positive and negative pions leading to $v_2(\\pi^+) < v_2(\\pi^-)$, and estimate the magnitude of the effect.
Kajimura, Y. [Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Japan Science and Technology Agency (JST), CREST 4-1-8 Hon-chou, Kawaguchi, Saitama 332-0012 (Japan); Matsuda, N.; Hayashida, K.; Maeno, A.; Nakashima, H. [Department of Advanced Energy Engineering Science, Interdisciplinary Graduate school of Engineering Sciences, Kyushu University, Kasugakouen 6-1, Kasuga, Fukuoka 816-580 (Japan)
2008-12-31
Numerical simulations of plasma behavior in a magnetic nozzle of a Laser-Plasma Driven Nuclear Electric Propulsion System are conducted. The propellant is heated and accelerated by the laser and expanded isotropically. The magnetic nozzle is a combination of solenoidal coils and used to collimate and guide the plasma to produce thrust. Simulation calculations by a three-dimensional hybrid code are conducted to examine the plasma behaviors in the nozzle and to estimate the thrust efficiency. We also estimate a fraction ({alpha}) of plasma particles leaking in the forward (spacecraft) direction. By a combination of a few coils, we could decrease {alpha} value without degrading the thrust efficiency. Finally, the shaped propellant is proposed to increase the thrust efficiency.
Aldegunde, J; Zuchowski, Piotr S \\; Hutson, Jeremy M
2008-01-01
We investigate the energy levels of heteronuclear alkali metal dimers in levels correlating with the lowest rotational level of the ground electronic state, which are important in efforts to produce ground-state ultracold molecules. We use density-functional theory to calculate nuclear quadrupole and magnetic coupling constants for RbK and RbCs and explore the hyperfine structure in the presence of electric and magnetic fields. For nonrotating states, the zero-field splittings are dominated by the electron-mediated part of the nuclear spin-spin coupling. They are a few kHz for RbK isotopologs and a few tens of kHz for RbCs isotopologs.
Charge state control in single InAs/GaAs quantum dots by external electric and magnetic fields
Tang, Jing; Cao, Shuo; Gao, Yunan; Sun, Yue; Jin, Kuijuan; Xu, Xiulai; Geng, Weidong; Williams, David A.
2014-07-28
We report a photoluminescence (PL) spectroscopy study of charge state control in single self-assembled InAs/GaAs quantum dots by applying electric and/or magnetic fields at 4.2?K. Neutral and charged exciton complexes were observed under applied bias voltages from ?0.5?V to 0.5?V by controlling the carrier tunneling. The highly negatively charged exciton emission becomes stronger with increasing pumping power, arising from the fact that electrons have a smaller effective mass than holes and are more easily captured by the quantum dots. The integrated PL intensity of negatively charged excitons is affected significantly by a magnetic field applied along the sample growth axis. This observation is explained by a reduction in the electron drift velocity caused by an applied magnetic field, which increases the probability of non-resonantly excited electrons being trapped by localized potentials at the wetting layer interface, and results in fewer electrons distributed in the quantum dots. The hole drift velocity is also affected by the magnetic field, but it is much weaker.
P. G. Harris; J. M. Pendlebury; N. E. Devenish
2013-06-05
Trapped ultracold neutrons (UCN) have for many years been the mainstay of experiments to search for the electric dipole moment (EDM) of the neutron, a critical parameter in constraining scenarios of new physics beyond the Standard Model. Because their energies are so low, UCN preferentially populate the lower region of their physical enclosure, and do not sample uniformly the ambient magnetic field throughout the storage volume. This leads to a substantial increase in the rate of depolarization, as well as to shifts in the measured frequency of the stored neutrons. Consequences for EDM measurements are discussed.
Massive gravity from bimetric gravity
Baccetti, Valentina; Visser, Matt
2012-01-01
We discuss the subtle relationship between so-called massive gravity (that is, gravity incorporating a non-zero graviton mass) and bimetric gravity, focussing particularly on the manner in which massive gravity may be viewed as a suitable limit of bimetric gravity. The limiting procedure is more delicate than currently appreciated, and in particular, in a cosmological context can lead to an interesting interplay between the "background" and "foreground" metrics. The fact that in bimetric theories one always has two sets of metric equations of motion, one for each metric, continues to have an effect even in the massive gravity limit. Thus, solutions of bimetric gravity in the limit of vanishing kinetic term are also solutions of massive gravity, but the contrary statement is not necessarily true.
Liouville gravity from Einstein gravity
D. Grumiller; R. Jackiw
2007-12-28
We show that Liouville gravity arises as the limit of pure Einstein gravity in 2+epsilon dimensions as epsilon goes to zero, provided Newton's constant scales with epsilon. Our procedure - spherical reduction, dualization, limit, dualizing back - passes several consistency tests: geometric properties, interactions with matter and the Bekenstein-Hawking entropy are as expected from Einstein gravity.
Magnetic and Electric Fields around the Black Hole in Cyg X-1
Yu. N. Gnedin; N. V. Borisov; T. M. Natsvlishvili; M. Yu. Piotrovich; N. A. Silant'ev
2003-04-09
Analysis of polarimetric observations of X-ray binary Cyg X-1/HDE 226868 including the data obtained by BTA-6m allows to estimate the magnetic field magnitude near the inner radius of the accretion disk. The magnetic field magnitude occurred to be $\\sim 10^{8}$ G. For power law of radial dependence of magnetic field into an accretion disk we estimates the value of an index of power law. For the Cyg X-1/HDE 226868 system the value of this index appears non less then two. If one accepts as a characteristic scale of a magnetic field generation region the dyadosphere radius, one can estimate the charge magnitude of a black hole. For Cyg X-1 this magnitude appears to be $\\sim 0.01M\\sqrt{G}$, where M is a black hole mass.
Bracken, T.D.; Rankin, R.F.; Wiley, J.A.
1999-05-01
The purpose of this project was to develop a conceptual model for estimating magnetic field (EMF) personal exposure (PE) of individuals or groups and construct a working model using existing data.
Authors A. L. Barabanov; R. Golub; S. K. Lamoreaux
2006-07-17
The search for particle electric dipole moments (edm) represents a most promising way to search for physics beyond the standard model. A number of groups are planning a new generation of experiments using stored gases of various kinds. In order to achieve the target sensitivities it will be necessary to deal with the systematic error resulting from the interaction of the well-known $\\overrightarrow{v}\\times \\overrightarrow{E}$ field with magnetic field gradients (often referred to as the geometric phase effect (Commins, ED; Am. J. Phys. \\QTR{bf}{59}, 1077 (1991), Pendlebury, JM \\QTR{em}{et al;} Phys. Rev. \\QTR{bf}{A70}, 032102 (2004)). This interaction produces a frequency shift linear in the electric field, mimicking an edm. In this work we introduce an analytic form for the velocity auto-correlation function which determines the velocity-position correlation function which in turn determines the behavior of the frequency shift (Lamoreaux, SK and Golub, R; Phys. Rev \\QTR{bf}{A71}, 032104 (2005)) and show how it depends on the operating conditions of the experiment. We also discuss some additional issues.
A. L. Barabanov; R. Golub; S. K. Lamoreaux
2005-12-20
The search for particle electric dipole moments represents a most promising way to search for physics beyond the standard model. A number of groups are planning a new generation of experiments using stored gases of various kinds. In order to achieve the target sensitivities it will be necessary to deal with the systematic error resulting from the interaction of the well-known E x v field with magnetic field gradients (often referred to as the geometric phase effect [9,10]). This interaction produces a frequency shift linear in the electric field, mimicking an edm. In this work we introduce an analytic model for the correlation function which determines the behavior of the frequency shift [11], and show in detail how it depends on the operating conditions of the experiment. We also propose a method to directly measure ths correlation function under the exact conditions of a given experiment.
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AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefield Municipal Gas &SCE-SessionsSouth DakotaRobbins and Myers CoMadison -T: Designation ofSEPE.ELECTRIC
Yu, Zejun; Li, Faxin; Pei, Yongmao, E-mail: peiym@pku.edu.cn, E-mail: fangdn@pku.edu.cn; Fang, Daining, E-mail: peiym@pku.edu.cn, E-mail: fangdn@pku.edu.cn [State Key Laboratory for Turbulence and Complex Systems, College of Engineering, Peking University, Beijing 100871 (China); Mao, Weiguo [Faculty of Materials and Optoelectronics Physics, Xiangtan University, Hunan 411105 (China); Feng, Xue [Department of Engineering Mechanics, Tsinghua University, Beijing 100084 (China)
2014-06-15
For the first time a novel multi-field bulge-test instrument which enables measurements of the biaxial mechanical properties and electro-magnetic-mechanical coupling effect of free-standing films in external magnetic/electric fields was proposed. The oil pressure was designed with two ranges, 0–1 MPa for elastic small deformation and 0–7 MPa for plastic/damage large deformation. A magnetic field that was horizontal and uniform in the film plane was supplied by a hollow cylindrical magnet. The magnitude could be changed from 0 to 10?000 Oe by adjusting the position of the testing film. Meanwhile, an electric field applied on the film was provided by a voltage source (Maximum voltage: 1000 V; Maximum current: 1 A). Various signals related to deformation, mechanical loading, magnetic field, and electric field could be measured simultaneously without mutual interference, which was confirmed by the coincidence of the measured P-H curves for titanium (Ti)/nickel (Ni) specimens with/without external fields. A hardening phenomenon under magnetic/electric fields was observed for Ni and lead zirconate titanate specimens. The multi-field bulge-test instrument will provide a powerful research tool to study the deformation mechanism of functional films and flexible electronics in the coupling field.
Richard W. Haymaker; Takayuki Matsuki
2003-10-07
Through the use of a lattice U(1) Ward-Takahashi identity, one can find a precise definition of flux and electric four-current that does not rely on the continuum limit. The magnetic four-current defined for example by the DeGrand-Toussaint construction introduces order a^2 errors in the field distributions. We advocate using a single definition of flux in order to be consistent with both the electric and magnetic Maxwell's equations at any lattice spacing. In a U(1) theory the monopoles are slightly smeared by this choice, i.e. are no longer associated with a single lattice cube. In Abelian projected SU(2) the consistent definition suggests further modifications. For simulations in the scaling window, we do not foresee large changes in the standard analysis of the dual Abrikosov vortex in the maximal Abelian gauge because the order a^2 corrections have small fluctuations and tend to cancel out. However in other gauges, the consequences of our definitions could lead to large effects which may help in understanding the choice of gauge. We also examine the effect of truncating all monopoles except for the dominant cluster on the profile of the dual Abrikosov vortex.
Eom, Chang Beom
Electric modulation of magnetization at the BaTiO3/La0.67Sr0.33MnO3 interfaces H. Lu, T. A. George. Phys. 113, 043914 (2013) Electrical control of magnetic reversal processes in magnetostrictive://apl.aip.org/about/rights_and_permissions #12;Electric modulation of magnetization at the BaTiO3/La0.67Sr0.33MnO3 interfaces H. Lu,1 T. A
Electric and geometric controlling of the magnetic coupling in Kane-Mele nanoribbons
Bao, Weicheng; Zou, Liang-Jian; Lin, H.-Q.
2015-05-07
In this paper, we show that indirect spin interaction J between two magnetic impurities located on honeycomb Kane-Mele zigzag/armchair ribbons (KMZR/KMAR) is easily controlled by staggered potential and geometry. We demonstrate that J in periodic-boundary KMZR reaches maximum at the edges, and oscillates between antiferromagnetic and ferromagnetic couplings when tuning the sublattice staggered potential ?. The odd-even length effect of J in KMZR and the width dependence of J in KMAR are also presented. These results clearly demonstrate the unique role of topological edge states and finite-size effect in magnetic coupling of quantum spin Hall (QSH) ribbons, and the controllability of the edge magnetism, hence favoring the fabrication of the spintronic devices in two-dimensional buckled honeycomb materials, e.g., silicene and germanene.
Electric and magnetic behaviors observed in NiO-based thin films under light-irradiation
Luo, Yi-Dong; Song, Kenan; Shun, Li; Gao, Junqi; Xu, Ben, E-mail: xuben@mail.tsinghua.edu.cn, E-mail: linyh@mail.tsinghua.edu.cn; Lin, Yuan-Hua, E-mail: xuben@mail.tsinghua.edu.cn, E-mail: linyh@mail.tsinghua.edu.cn; Nan, Ce-Wen; Liu, Wei [State Key Laboratory of New Ceramics and Fine Processing, School of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China)
2014-09-07
We report the room-temperature ferromagnetic properties that can be tuned by light irradiation in the Li and Mn co-doped NiO films (LMNO) grown by the spinning coating. The optical tunable magnetic behavior is enhanced by the increase of the Li doping concentration. First-principle calculations reveal that the Li doping plays key roles in the optical tuned magnetic behavior, which brings a 3d-like impurity state to enhance a significant hybridization between the Mn{sup 3+} 3d state and the impurity band, thus strengthening the ferromagnetic coupling effects. Additionally, it can tune the band gap of the LMNO films and produce more holes under the light irradiation, enhancing the optical tuned magnetic behavior.
Brodsky, S J; Hwang, D S
2006-01-01
We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo ...
Electric-field-induced strain effects on the magnetization of a Pr0.67Sr0.33MnO3 film
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhang, B.; Sun, C. -J.; Lu, W.; Venkatesan, T.; Han, M. -G.; Zhu, Y.; Chen, J.; Chow, G. M.
2015-05-26
The electric-field control of magnetic properties of Pr0.67Sr0.33MnO3 (PSMO) film on piezoelectric Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMNT) substrate was investigated. The piezoelectric response of the PMNT substrate to the electric field produced strain that was coupled to the PSMO film. The in-plane compressive (tensile) strain increased (decreased) the magnetization. The change of magnetic moment was associated with the Mn ions. First principle simulations showed that the strain-induced electronic redistribution of the two eg orbitals (3dz2 and 3dx2-y2) of Mn ions was responsible for the change of magnetic moment. This work demonstrates that the magnetoelectric effect in manganite/piezoelectric hetero-structures originates from the change inmore »eg orbital occupancy of Mn ions induced by strain rather than the interfacial effect.« less
2012-01-01
REACT Project: The University of Alabama is developing new iron- and manganese-based composite materials for use in the electric motors of EVs and renewable power generators that will demonstrate magnetic properties superior to today’s best rare-earth-based magnets. Rare earths are difficult and expensive to refine. EVs and renewable power generators typically use rare earths to make their electric motors smaller and more powerful. The University of Alabama has the potential to improve upon the performance of current state-of-the-art rare-earth-based magnets using low-cost and more abundant materials such as manganese and iron. The ultimate goal of this project is to demonstrate improved performance in a full-size prototype magnet at reduced cost.
Superconductive Magnetic Energy Storage (SMES) System Studies for Electrical Utility at Wisconsin
Boom, R. W.; Eyssa, Y. M.; Abdelsalem, M. K.; Huang, X.
1988-01-01
.ooldown, warmllp lind dally magnetic load cycllng. TROUGH PLANK ~ Scm 00 CONDUCTOR 0 1 ~\\I'I IBj ~ 'INSULATOR I I",.--------e2cm . fig. S. Cros~ section view of non-rippled SM~S. Trough and plank are diacontinuous. PLANK GAP TROUGH GAP / ,/ -11-' 10...
Comment on "High-Precision Determination of the Electric and Magnetic Form Factors of the Proton"
J. Arrington
2011-08-15
In a recent Letter, Bernauer, et al. present fits to the proton electromagnetic form factors, GEp(Q^2) and GMp(Q^2), along with extracted proton charge and magnetization radii based on large set of new, high statistical precision (<0.2%) cross section measurements. The Coulomb corrections they apply differ dramatically from more modern and complete calculations, implying significant error in their final results.
Tomislav Ivezi?
2008-09-30
The usual transformations of the three-dimensional (3D) fields E and B that are found in [1] ([1] A. Einstein, Ann. Physik \\17, 891 (1905)) are always considered to be the relativistically correct Lorentz transformations (LT) of E and B. However, as proved in, e.g., [2] ([2] T. Ivezi\\'c, Found. Phys. Lett. 18, 301 (2005)), these transformations drastically differ from the LT of the relativistically correct 4D electric and magnetic fields. In this paper a simple proof of that difference will be presented and the consequences for EDM experiments and for some quantum phase shifts experiments are briefly examined. In all such experiments the usual 3D quantities, e.g., E, B, ... are measured and their relativistically incorrect transformations are used, but not the relativistically correct 4D geometric quantities, e.g., E^a, B^a, ... and their LT.
K. Bakke; H. Belich
2015-07-14
We investigate the arising of an analogue of the Landau quantization from a background of the violation of the Lorentz symmetry established by a time-like 4-vector and a field configuration of crossed electric and magnetic field. We also analyse the effects on this Landau-type system subject to a hard-wall confining potential by showing a particular case where a discrete spectrum of energy can be obtained. Further, we analyse the effects of a linear confining potential on the Landau-type system. We show that a quantum effect characterized by the dependence of the cyclotron frequency on the quantum numbers of the system can arise in this analogue of the Landau system. As an example, we calculate the cyclotron frequency associated with ground state of the system.
Electric magnetic duality of the confining flux tube in Abelian-projected gluodynamics
Yoshiaki Koma
2002-12-30
The structure of the Abelian-projected (AP) flux tube in SU(2) gauge theory in the maximally Abelian gauge is studied by applying the Hodge decomposition to the Abelian Wilson loop. It is shown that the profile of the AP flux tube has the same structure as the classical flux tube solution in the dual Abelian Higgs model, which is composed of a Coulombic and a solenoidal electric field linked by monopole supercurrent.
Ground Gravity Survey At San Francisco Volcanic Field Area (Warpinski...
geologically mapped the target area, obtained rock samples for age dating and mineral chemistry, performed gravity and magnetic surveys, and integrated these results to identify...
Wysin, Gary
Physics II Exam 2 - Chs. 18A,19,20 - Electric Current, Magnetic Field Feb. 23, 2009 Name Rec. Instr-hours, the quantity 850 amp-hours must be a. power. b. energy. c. current. d. charge. b) (4) Give 850 amp-hours in SI
Einstein Gravity from Conformal Gravity
Juan Maldacena
2011-06-09
We show that that four dimensional conformal gravity plus a simple Neumann boundary condition can be used to get the semiclassical (or tree level) wavefunction of the universe of four dimensional asymptotically de-Sitter or Euclidean anti-de Sitter spacetimes. This simple Neumann boundary condition selects the Einstein solution out of the more numerous solutions of conformal gravity. It thus removes the ghosts of conformal gravity from this computation. In the case of a five dimensional pure gravity theory with a positive cosmological constant we show that the late time superhorizon tree level probability measure, $|\\Psi [ g ]|^2$, for its four dimensional spatial slices is given by the action of Euclidean four dimensional conformal gravity.
Lasche, G.P.
1988-04-05
A method for recovering energy in an inertial confinement fusion reactor having a reactor chamber and a sphere forming means positioned above an opening in the reactor chamber is described, comprising: embedding a fusion target fuel capsule having a predetermined yield in the center of a hollow solid lithium tube and subsequently embedding the hollow solid lithium tube in a liquid lithium medium; using the sphere forming means for forming the liquid lithium into a spherical shaped liquid lithium mass having a diameter smaller than the length of the hollow solid lithium tube with the hollow solid lithium tube being positioned along a diameter of the spherical shaped mass, providing the spherical shaped liquid lithium mass with the fusion fuel target capsule and hollow solid lithium tube therein as a freestanding liquid lithium shaped spherical shaped mass without any external means for maintaining the spherical shape by dropping the liquid lithium spherical shaped mass from the sphere forming means into the reactor chamber; producing a magnetic field in the reactor chamber; imploding the target capsule in the reactor chamber to produce fusion energy; absorbing fusion energy in the liquid lithium spherical shaped mass to convert substantially all the fusion energy to shock induced kinetic energy of the liquid lithium spherical shaped mass which expands the liquid lithium spherical shaped mass; and compressing the magnetic field by expansion of the liquid lithium spherical shaped mass and recovering useful energy.
Basu, Debjyoti; Pal, Rabindranath [Saha Institute of Nuclear Physics, 1/AF-Bidhannagar, Kolkata 700064 (India); Ghosh, Joydeep; Chattopadhyay, Prabal K. [Institute for Plasma Research, Bhat, Gandhinagar 382428 (India)
2012-07-15
Improvement of plasma confinement is achieved in normal q{sub a} discharges of SINP-tokamak by introducing a biased electrode inside the last closed flux surface. All the important features of high confinement mode are observed biasing the electrode negatively with respect to the vacuum vessel. Arrays of electric and magnetic probes introduced in the edge plasma region reveal suppression of electric and magnetic fluctuations over distinct frequency ranges as well as modification of the toroidal current profile due to biasing. Further analysis identifies the electrostatic fluctuations to be due to drift mode and the magnetic fluctuations may be of slow compressional Alfven waves. Both get suppressed due to current profile modification during biasing, hence leading to the improvement of plasma confinement.
Unification of Gravity and Electromagnetism I: Mach's Principle and Cosmology
Partha Ghose
2015-02-12
The phenomenological consequences of unification of Einstein gravity and electromagnetism in an early phase of a Machian universe with a very small and uniform electrical charge density $\\rho_q$ are explored. A form of the Strong Equivalence Principle for unified electrogravity is first formulated, and it immediately leads to (i) the empirical Schuster-Blackett law relating the magnetic moments and angular momenta of neutral astronomical bodies, (ii) an analogous relation between the linear acceleration of neutral massive bodies and associated electric fields, (iii) gravitational lensing in excess of Einstein gravity, and, with the additional assumption of scaling, to (iv) the Wesson relation between the angular momentum and the square of the mass of astronomical bodies. Incorporation of Sciama's version of Mach's principle leads to a new post-Newtonian dynamics (in the weak field limit of gravity alone without electromagnetism) that predicts flat rotation curves of galaxies without the need of dark matter haloes. Finally, it is shown that the unified theory with a broken symmetry predicts a flat expanding universe with a cosmological term intimately related to electrogravity unification, and can explain WMAP data with a single free parameter. WMAP data require $\\rho_q =6.1\\times 10^{-43}$ C/cc which is too small to be detected at
Kushwaha, Varun Sharma, Himanshu Dixit, Dinesh Tomy, C. V.; Tulapurkar, Ashwin
2014-04-24
We have studied the effects of Co and Fe doping on the magnetic and electrical properties of half-Heusler compound NiMnSb. The alloys were prepared by arc-melting method in the presence of Argon gas. The powder X-ray diffraction of the each alloy was performed in air at room temperature. The magnetic and electrical properties were performed in the temperature range 2–400 K and in magnetic field up to 1 T.
Lujan, Richard E. (Santa Fe, NM)
2001-01-01
A mechanical gravity brake that prevents hoisted loads within a shaft from free-falling when a loss of hoisting force occurs. A loss of hoist lifting force may occur in a number of situations, for example if a hoist cable were to break, the brakes were to fail on a winch, or the hoist mechanism itself were to fail. Under normal hoisting conditions, the gravity brake of the invention is subject to an upward lifting force from the hoist and a downward pulling force from a suspended load. If the lifting force should suddenly cease, the loss of differential forces on the gravity brake in free-fall is translated to extend a set of brakes against the walls of the shaft to stop the free fall descent of the gravity brake and attached load.
Electric field induced spin and valley polarization within a magnetically confined silicene channel
Liu, Yiman; Zhou, Xiaoying; Zhou, Ma; Zhou, Guanghui; Long, Meng-Qiu
2014-12-28
We study the electronic structure and transport properties of Dirac electrons along a channel created by an exchange field through the proximity of ferromagnets on a silicene sheet. The multiple total internal reflection induces localized states in the channel, which behaves like an electron waveguide. An effect of spin- and valley-filtering originating from the coupling between valley and spin degrees is predicted for such a structure. Interestingly, this feature can be tuned significantly by locally applying electric and exchange fields simultaneously. The parameter condition for observing fully spin- and valley-polarized current is obtained. These findings may be observable in todays' experimental technique and useful for spintronic and valleytronic applications based on silicene.
Test particle motion in modified gravity theories
Mahmood Roshan
2013-02-05
We derive the equations of motion of an electrically neutral test particle for modified gravity theories in which the covariant divergence of the ordinary matter energy-momentum tensor dose not vanish (i.e. $\
Transition between vortex rings and MAP solutions for electrically charged magnetic solutions
Wong, Khai-Ming; Soltanian, Amin; Teh, Rosy
2014-03-05
We consider the bifurcation and transition of axially symmetric monopole-antimonopole pair (MAP) and vortex ring solutions in the presence of electric charge for the SU(2) Yang-Mills-Higgs field theory. Here we investigate the properties of MAP/vortex ring solutions with n = 3,? = 0.65, for different Higgs field strength ?. For ? < 4.93, there is only one fundamental branch of vortex ring solution, but at the critical value of ?{sub b} = 4.93, branching happens and 2 sets of new solutions appeared. The new branch with less energy is a full MAP solution while the branch with higher energy contains MAP at the beginning and separation between poles of MAP on the z-axis reduces gradually and at another critical value of ?{sub t} = 14.852, they merge together at z = 0. Beyond this point the solutions change to the vortex ring solutions and a transitions between MAP and vortex ring solutions happens at this branch.
Vladimir G. Baryshevsky; Alexander J. Silenko
2010-11-10
Measurement of the tensor electric and magnetic polarizabilities of the deuteron is of great interest, especially in connection with the possibilities of COSY and GSI. These polarizabilities can be measured in storage rings by the frozen spin method providing a disappearance of g-2 precession. This method will be used in the planned deuteron electric-dipole-moment experiment in storage rings. The tensor electric polarizability of the deuteron significantly influences the buildup of the vertical polarization in the above experiment. The spin interactions depending on the electric dipole moment, the tensor electric polarizability, and main systematical errors caused by field misalignments have very different symmetries. For the considered experimental conditions, the sensitivity to the deuteron EDM of $1\\times10^{-29} e\\cdot$cm corresponds to measuring the both of tensor polarizabilities with an accuracy of $\\delta\\alpha_T\\approx\\delta\\beta_T\\approx5\\times10^{-42}$ cm$^3$. This conservative estimate can be improved by excluding the systematical error caused by the field instability which is negligible for the measurement of the tensor polarizabilities. To find the tensor magnetic polarizability, the horizontal components of the polarization vector should be measured.
Hegerfeldt, G.C.; Henneberg, R. (Institut fuer Theoretische Physik, University of Goettingen, D-37073 Goettingen (Germany))
1994-05-01
The statistical analysis of energy levels, a powerful tool in the study of quantum systems, is applicable to discrete spectra. Here we propose an approach to carry level statistics over to continuous energy spectra, paradoxical as this may sound at first. The approach proceeds in three steps, first a discretization of the spectrum by cutoffs, then a statistical analysis of the resulting discrete spectra, and finally a determination of the limit distributions as the cutoffs are removed. In this way the notions of Wigner and Poisson distributions for nearest-neighbor spacing (NNS), usually associated with quantum chaos and regularity, can be carried over to systems with a purely continuous energy spectrum. The approach is demonstrated for the hydrogen atom in perpendicular electric and magnetic fields. This system has a purely continuous energy spectrum from [minus][infinity] to [infinity]. Depending on the field parameters, we find for the NNS a Poisson or a Wigner distribution, or a transitional behavior. We also outline how to determine physically relevant resonances in our approach by a stabilization method.
Co', G; Anguiano, M; Bernard, R N; Lallena, A M
2015-01-01
We present a model which describes the properties of odd-even nuclei with one nucleon more, or less, with respect to the magic number. In addition to the effects related to the unpaired nucleon, we consider those produced by the excitation of the closed shell core. By using a single particle basis generated with Hartree-Fock calculations, we describe the polarization of the doubly magic-core with Random Phase Approximation collective wave functions. In every step of the calculation, and for all the nuclei considered, we use the same finite-range nucleon-nucleon interaction. We apply our model to the evaluation of electric quadrupole and magnetic dipole moments of odd-even nuclei around oxygen, calcium, zirconium, tin and lead isotopes. Our Random Phase Approximation description of the polarization of the core improves the agreement with experimental data with respect to the predictions of the independent particle model. We compare our results with those obtained in first-order perturbation theory, with those ...
G. Co'; V. De Donno; M. Anguiano; R. N. Bernard; A. M. Lallena
2015-09-08
We present a model which describes the properties of odd-even nuclei with one nucleon more, or less, with respect to the magic number. In addition to the effects related to the unpaired nucleon, we consider those produced by the excitation of the closed shell core. By using a single particle basis generated with Hartree-Fock calculations, we describe the polarization of the doubly magic-core with Random Phase Approximation collective wave functions. In every step of the calculation, and for all the nuclei considered, we use the same finite-range nucleon-nucleon interaction. We apply our model to the evaluation of electric quadrupole and magnetic dipole moments of odd-even nuclei around oxygen, calcium, zirconium, tin and lead isotopes. Our Random Phase Approximation description of the polarization of the core improves the agreement with experimental data with respect to the predictions of the independent particle model. We compare our results with those obtained in first-order perturbation theory, with those produced by Hartree-Fock-Bogolioubov calculations and with those generated within the Landau-Migdal theory of finite Fermi systems. The results of our universal, self-consistent, and parameter free approach have the same quality of those obtained with phenomenological approaches where the various terms of the nucleon-nucleon interaction are adapted to reproduce some specific experimental data. A critical discussion on the validity of the model is presented.
Vijayan, Lakshmi [St. Aloysius College, Edathua, Alappuzha (District), Kerala 689573 (India); Cheruku, Rajesh [Department of Physics, School of Physical, Chemical and Applied Sciences, Pondicherry University, R.V. Nagar, Kalapet, Pondicherry 605 014 (India); Govindaraj, G., E-mail: ggraj_7@yahoo.com [Department of Physics, School of Physical, Chemical and Applied Sciences, Pondicherry University, R.V. Nagar, Kalapet, Pondicherry 605 014 (India)
2014-02-01
Highlights: • Solution combustion technique and preparation of nanocrystalline olivine materials. • Olivine type LiNiPO{sub 4} based nanocrystalline materials and characterization. • AC electrical studies on olivine type LiNi{sub 1?x}M{sub x}PO{sub 4}(M = Cu{sup 2+}/Mg{sup 2+})based materials. • Enhancement of ionic conductivity in the nanocrystalline phase of LiNiPO{sub 4} material. - Abstract: Citric acid assisted solution combustion technique is explored for synthesis of supervalent Cu{sup 2+}/Mg{sup 2+} ion doped LiNiPO{sub 4} system. XRD, FT-IR and microscopy studies confirmed the formation of a well crystallized material at low concentration of dopants. Ionic conductivity increases for lower concentrations of dopants due to the increased channel size for Li{sup +} diffusion. Owing to inherent anti-site defects, ionic conductivity decreases with increase of dopant concentration. Magnetic studies are explored for confirmation of antiferromagnetic nature of ions. Wagner polarization method is used to elucidate the negligible contribution of electrons to total conductivity.
Woolley, Robert D. (Belle Mead, NJ)
1999-01-01
A method for integrating liquid metal magnetohydrodynamic power generation with fusion blanket technology to produce electrical power from a thermonuclear fusion reactor located within a confining magnetic field and within a toroidal structure. A hot liquid metal flows from a liquid metal blanket region into a pump duct of an electromagnetic pump which moves the liquid metal to a mixer where a gas of predetermined pressure is mixed with the pressurized liquid metal to form a Froth mixture. Electrical power is generated by flowing the Froth mixture between electrodes in a generator duct. When the Froth mixture exits the generator the gas is separated from the liquid metal and both are recycled.
Gravity Data for west-central Colorado
Zehner, Richard
2012-04-06
Modeled Bouger Gravity data was extracted from the Pan American Center for Earth and Environmental Studies Gravity Database of the U.S. at http://irpsrvgis08.utep.edu/viewers/Flex/GravityMagnetic/GravityMagnetic_CyberShare/ on 2/29/2012. The downloaded text file was opened in an Excel spreadsheet. This spreadsheet data was then converted into an ESRI point shapefile in UTM Zone 13 NAD27 projection, showing location and gravity (in milligals). This data was then converted to grid and then contoured using ESRI Spatial Analyst. This dataset contains the original spreadsheet data, a point shapefile showing gravity station locations and Bouger gravity, and a line shapefile showing 1 milligal contours. Projection: UTM Zone 13 NAD27 Gravity Contour Shapefile Extent: West -108.366690 East -105.478730 North 40.932318 South 36.961606 Gravity Point Shapefile Extent: West -108.366692 East -105.478847 North 40.932361 South 36.961606 Data from From University of Texas: Pan American Center for Earth and Environmental Studies
Egedal, Jan; Le, Ari; Borg, Anette L
2015-01-01
Using a kinetic simulation of magnetic reconnection it was recently shown that magnetic-field-aligned electric fields (E||) can be present over large spatial scales in reconnection exhausts. The largest values of E|| are observed within double layers. The existence of double layers in the Earth's magnetosphere is well documented. In our simulation their formation is triggered by large parallel streaming of electrons into the reconnection region. These parallel electron fluxes are required for maintaining quasi-neutrality of the reconnection region and increase with decreasing values of the normalized electron pressure upstream of the reconnection region. A threshold normalized pressure is derived for strong double layers to develop. We also document how the electron confinement, provided in part by the structure in E||, allows sustained energization by perpendicular electric fields. The energization is a consequence of the confined electrons' chaotic orbital motion that includes drifts aligned with the reconn...
Claus W. Turtur
2007-11-23
As generally known, the speed of propagation of light in solid state bodies can be different from the speed of light in vacuum. That the mere presence of electric or magnetic fields in the vacuum can suffice to influence the speed of light, is a hypothesis under discussion, which is based on considerations of Quantumelectrodynamics. For a verification of this hypothesis, an interference-experiment might be performed, of which the planning is given in this article.
Baghdadi, M.; Ruiz, H. S.; Fagnard, J. F.; Zhang, M.; Wang, W.; Coombs, T. A.
2014-11-24
to a nitrogen reservoir. Having several materials with different expansion rates, we employed finite element analysis to be confident that the experimental rig can be safely used at low temperature, 77 K. In all the experiments, the wider surface... path for magnetic flux and, subsequently, shield against static or slowly varying magnetic fields. It should be noted that µ-metal is saturated at low magnetic field, therefore, using several layers is advised; each layer shields a fraction of magnetic...
Is nonrelativistic gravity possible?
Kocharyan, A. A.
2009-07-15
We study nonrelativistic gravity using the Hamiltonian formalism. For the dynamics of general relativity (relativistic gravity) the formalism is well known and called the Arnowitt-Deser-Misner (ADM) formalism. We show that if the lapse function is constrained correctly, then nonrelativistic gravity is described by a consistent Hamiltonian system. Surprisingly, nonrelativistic gravity can have solutions identical to relativistic gravity ones. In particular, (anti-)de Sitter black holes of Einstein gravity and IR limit of Horava gravity are locally identical.
Tomislav Ivezic
2012-11-02
In the first part of this paper we review the fundamental difference between the usual transformations of the three-dimensional (3D) vectors of the electric field $\\mathbf{E}$, the magnetic field $\\mathbf{B}$, the polarization $\\mathbf{P}$, the magnetization $\\mathbf{M}$ and the Lorentz transformations of the 4D geometric quantities, vectors E, B, P, M, with many additional explanations and several new results. In the second part, we have discussed the existence of the electric field vector E outside a stationary superconducting wire with a steady current and also different experiments for the detection of such electric fields. Furthermore, a fundamental prediction of the existence of the external electric field vector E from a stationary permanent magnet is considered. These electric fields are used for the resolution of the "charge-magnet paradox" with 4D geometric quantities for a qualitative explanation of the Aharonov-Bohm effect in terms of fields and not, as usual, in terms of the vector potential and for a qualitative explanation that the particle interference is not a test of a Lorentz-violating model of electrodynamics according to which a magnetic solenoid generates not only a static magnetic field but also a static electric field.
B. L. Hu
1999-02-22
We give a summary of the status of current research in stochastic semiclassical gravity and suggest directions for further investigations. This theory generalizes the semiclassical Einstein equation to an Einstein-Langevin equation with a stochastic source term arising from the fluctuations of the energy-momentum tensor of quantum fields. We mention recent efforts in applying this theory to the study of black hole fluctuations and backreaction problems, linear response of hot flat space, and structure formation in inflationary cosmology. To explore the physical meaning and implications of this stochastic regime in relation to both classical and quantum gravity, we find it useful to take the view that semiclassical gravity is mesoscopic physics and that general relativity is the hydrodynamic limit of certain spacetime quantum substructures. Three basic issues - stochasticity, collectivity, correlations- and three processes - dissipation, fluctuations, decoherence- underscore the transformation from quantum micro structure and interaction to the emergence of classical macro structure and dynamics. We discuss ways to probe into the high energy activity from below and make two suggestions: via effective field theory and the correlation hierarchy. We discuss how stochastic behavior at low energy in an effective theory and how correlation noise associated with coarse-grained higher correlation functions in an interacting quantum field could carry nontrivial information about the high energy sector. Finally we describe processes deemed important at the Planck scale, including tunneling and pair creation, wave scattering in random geometry, growth of fluctuations and forms, Planck scale resonance states, and spacetime foams.
O. V. Veko; K. V. Kazmerchuk; E. M. Ovsiyuk; V. V. Kisel; V. M. Red'kov
2014-11-07
Relativistic theory of the Cox's scalar not point-like particle with intrinsic structure is developed on the background of arbitrary curved space-time. It is shown that in the most general form, the extended Proca-like tensor first order system of equations contains non minimal interaction terms through electromagnetic tensor F_{\\alpha \\beta} and Ricci tensor R_{\\alpha \\beta}. In relativistic Cox's theory, the limiting procedure to non-relativistic approximation is performed in a special class of curved space-time models. This theory is specified in simple geometrical backgrounds: Euclid's, Lobachevsky's, and Rie\\-mann's. Wave equation for the Cox's particle is solved exactly in presence of external uniform magnetic and electric fields in the case of Minkowski space. Non-trivial additional structure of the particle modifies the frequency of a quantum oscillator arising effectively in presence if external magnetic field. Extension of these problems to the case of the hyperbolic Lobachevsky space is examined. In presence of the magnetic field, the quantum problem in radial variable has been solved exactly; the quantum motion in z-direction is described by 1-dimensional Schr\\"{o}dinger-like equation in an effective potential which turns out to be too difficult for analytical treatment. In the presence of electric field, the situation is similar. The same analysis has been performed for spherical Riemann space model.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Ni, Yan; Zhang, Zhen; Nlebedim, Cajetan I.; Jiles, David C.
2015-03-20
Multiferroic materials exhibit magnetoelectric (ME) coupling and promise new device applications including magnetic sensors, generators, and filters. An effective method for developing ME materials with enhanced ME effect is achieved by the coupling through the interfacial strain between piezoelectric and magnetostrictive materials. In this study, the electrical and magnetic properties of Ga doped magnetoelectric CoGaxFe2–xO4/BaTiO3 composite are studied systematically. It is found that Ga doping improves the sensitivity of magnetoelastic response and stabilizes the magnetic phase of the composites. More importantly, Ga doping reduces the electrical conductivity of composite, as well as the dielectric loss. An enhancement of the electrostrainmore »with doping Ga is also observed. Quantitative estimation indicates that magnetoelectric coupling is enhanced for Ga-doped CoGaxFe2–xO4/BaTiO3 composites. As a result, the present work is beneficial to the practical application of composite CoFe2O4/BaTiO3-based multiferroic materials.« less
Y. V. Stadnik; V. V. Flambaum
2015-02-24
We show that the interaction of an axion field, or in general a pseudoscalar field, with the axial-vector current generated by an electron through a derivative-type coupling can give rise to a time-dependent mixing of opposite-parity states in atomic and molecular systems. Likewise, the analogous interaction of an axion field with the axial-vector current generated by a nucleon can give rise to time-dependent mixing of opposite-parity states in nuclear systems. This mixing can induce oscillating electric dipole moments, oscillating parity non-conservation effects and oscillating anapole moments in such systems. By adjusting the energy separation between the opposite-parity states of interest to match the axion mass energy, axion-induced experimental observables can be enhanced by many orders of magnitude. Oscillating atomic electric dipole moments can also be generated by axions through hadronic mechanisms, namely the P,T-violating nucleon-nucleon interaction and through the axion-induced electric dipole moments of valence nucleons, which comprise the nuclei. The axion field is modified by the Earth's gravitational field. The interaction of the spin of either an electron or nucleon with this modified axion field leads to axion-induced observable effects. These effects, which are of the form $\\mathbf{g} \\cdot \\mathbf{\\sigma}$, differ from the axion-wind effect, which has the form $\\mathbf{p}_{\\textrm{a}} \\cdot \\mathbf{\\sigma}$.
Hanson, Andrew J.
2011-01-01
more restrictive context of Einstein's theory of gravity.6782 TORSION AND QUANTUM GRAVITY Andrevr J, Him son Lawrencetorsion in conventional gravity cou~d in fact be dynamicaL A
Hang, Alice Thanh
2009-01-01
The front speed of intrusive gravity currents. J. FluidP.F. Linden. Intrusive gravity currents. J. Fluid Mechanics,of mesoscale variability of gravity waves. Part II: Frontal,
. Terbium Double-Decker 1 S3. Nuclear Spin Read-Out 2 S4. Quantum Tunnelling of Magnetization 3 S5. Quantum magnetic field sweeps in three dimensions at field sweep rates up to 0.2 T/s. S2. TERBIUM DOUBLE-DECKER We
Judkins, R.R.; Burchell, T.D.
1999-07-20
A method for separating gases or other fluids involves placing a magnetic field on a monolithic carbon fiber composite sorption material to more preferentially attract certain gases or other fluids to the sorption material to which a magnetic field is applied. This technique may be combined with the known pressure swing adsorption'' technique utilizing the same sorption material. 1 fig.
Aad, Georges; ATLAS Collaboration; Abdallah, Jalal; Abdinov, Ovsat; Aben, Rosemarie; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Affolder, Tony; Agatonovic-Jovin, Tatjana; Agricola, Johannes; Aguilar-Saavedra, Juan Antonio; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Alkire, Steven Patrick; Allbrooke, Benedict; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; ?lvarez Piqueras, Damián; Alviggi, Mariagrazia; Amadio, Brian Thomas; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anders, John Kenneth; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, Bradley; Ayoub, Mohamad Kassem; Azuelos, Georges; Baak, Max; Baas, Alessandra; Baca, Matthew John; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Baldin, Evgenii; Balek, Petr; Balestri, Thomas; Balli, Fabrice; Balunas, William Keaton; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Bansil, Hardeep Singh; Barak, Liron; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Basalaev, Artem; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Bauce, Matteo; Bauer, Florian; Bawa, Harinder Singh; Beacham, James Baker; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Kathrin; Becker, Maurice; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Janna Katharina; Belanger-Champagne, Camille; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bender, Michael; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Beresford, Lydia; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Beringer, Jürg; Bernard, Clare; Bernard, Nathan Rogers; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertsche, Carolyn; Bertsche, David; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia Bylund, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bevan, Adrian John; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Biedermann, Dustin; Bieniek, Stephen Paul; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina
2015-01-01
A search for highly ionizing particles produced in proton-proton collisions at 8 TeV center-of-mass energy is performed by the ATLAS collaboration at the CERN Large Hadron Collider. The dataset used corresponds to an integrated luminosity of 7.0 fb$^{-1}$. A customized trigger significantly increases the sensitivity, permitting a search for such particles with charges and energies beyond what was previously accessible. No event is found in the signal region, leading to production cross-section upper limits in the mass range 200--2500 GeV for magnetic monopoles with magnetic charge in the range $0.5g_{D}electric charge in the range $10<|z|<60$. Model-dependent limits are presented in given pair-production scenarios, and model-independent limits are presented in fiducial regions of particle energy and pseudorapidity.
ATLAS Collaboration
2015-09-27
A search for highly ionizing particles produced in proton-proton collisions at 8 TeV center-of-mass energy is performed by the ATLAS collaboration at the CERN Large Hadron Collider. The dataset used corresponds to an integrated luminosity of 7.0 fb$^{-1}$. A customized trigger significantly increases the sensitivity, permitting a search for such particles with charges and energies beyond what was previously accessible. No event is found in the signal region, leading to production cross-section upper limits in the mass range 200-2500 GeV for magnetic monopoles with magnetic charge in the range $0.5g_{D}electric charge in the range $10<|z|<60$. Model-dependent limits are presented in given pair-production scenarios, and model-independent limits are presented in fiducial regions of particle energy and pseudorapidity.
Yang, X. Y.; Chen, Y. H.; Lin, C.; Wang, X. G.; Xiao, C. J., E-mail: cjxiao@pku.edu.cn [State Key Labaratory of Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Wang, L. [Institute of Physics, Chinese Academy of Sciences, P.O. Box 603, Beijing 100190 (China); Xu, M. [Center for Fusion Science of Southwestern Institute of Physics, P.O. Box 432, Chengdu 610041 (China)
2014-11-15
Both the poloidal magnetic field (B{sub p}) and radial electric field (E{sub r}) are significant in magnetic confinement devices. In this paper, a new method was proposed to diagnose both B{sub p} and E{sub r} at the same time, which was named Laser-accelerated Ion-beam Trace Probe (LITP). This method based on the laser-accelerated ion beam, which has three properties: large energy spread, short pulse lengths, and multiple charge states. LITP can provide the 1D profiles, or 2D images of both B{sub p} and E{sub r}. In this paper, we present the basic principle and some preliminary theoretical results.
Lensless Imaging of Magnetic Nanostructures
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying...
Correa, J. D.; Mora-Ramos, M. E.; Duque, C. A.
2014-06-07
We report a study on the optical absorption coefficient associated to hydrogenic impurity interstate transitions in zinc-blende GaN quantum wires of cylindrical shape taking into account the effects of externally applied static electric and magnetic fields. The electron states emerge within the effective mass approximation, via the exact diagonalization of the donor-impurity Hamiltonian with parabolic confinement and external field effects. The nonlinear optical absorption is calculated using a recently derived expression for the dielectric susceptibility, obtained via a nonperturbative solution of the density-matrix Bloch equation. Our results show that this treatment eliminates not only the intensity-dependent bleaching effect but also the change in sign of the nonlinear contribution due to the combined effect of asymmetric impurity location and the applied electric field.
Sub-Kelvin magnetic and electrical measurements in a diamond anvil cell with in-situ tunability
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Palmer, Alexander; Silevitch, Daniel; Feng, Yejun; Wang, Yishu; Jaramillo, R.; Banerjee, Arnab; Ren, Yang; Rosenbaum, Thomas F.
2015-09-04
We discuss techniques for performing continuous measurements across a wide range of pressure-field-temperature phase space, combining the milli-Kelvin temperatures of a helium dilution refrigerator with that of the giga-Pascal pressures of a diamond anvil cell and the Tesla magnetic fields of a superconducting magnet. With a view towards minimizing remnant magnetic fields and background magnetic susceptibility, we then characterize high-strength superalloy materials for the pressure cell assembly, which allows high fidelity measurements of low-field phenomena such as superconductivity below 100 mK at pressures above 10 GPa. In situ tunability and measurement of the pressure permit experiments over a wide rangemore »of pressure, while at the same time making possible precise steps across abrupt phase transitions such as that from insulator to metal.« less
S. K. Lamoreaux; R. Golub
2005-01-25
The search for particle electric dipole moments (edm) is one of the best places to look for physics beyond the standard model because the size of time reversal violation predicted by the standard model is incompatible with present ideas concerning the creation of the Baryon-Antibaryon asymmetry. As the sensitivity of these edm searches increases more subtle systematic effects become important. We develop a general analytical approach to describe a systematic effect recently observed in an electric dipole moment experiment using stored particles \\cite{JMP}. Our approach is based on the relationship between the systematic frequency shift and the velocity autocorrelation function of the resonating particles. Our results, when applied to well-known limiting forms of the correlation function, are in good agreement with both the limiting cases studied in recent work that employed a numerical/heuristic analysis. Our general approach explains some of the surprising results observed in that work and displays the rich behavior of the shift for intermediate frequencies, which has not been previously studied.
S. B. Chernyshuk; O. M. Tovkach; B. I. Lev
2011-09-14
The Green function method developed in Ref.[S. B. Chernyshuk and B. I. Lev, Phys. Rev. E \\textbf{81}, 041707 (2010)] is used to describe elastic interactions between axially symmetric colloidal particles in the nematic cell in the presence of the external electric or magnetic field. General formulas for dipole-dipole, dipole-quadrupole and quadrupole-quadrupole interactions in the homeotropic and planar nematic cells with parallel and perpendicular field orientations are obtained. A set of new results has been predicted: 1) \\textit{Deconfinement effect} for dipole particles in the homeotropic nematic cell with negative dielectric anisotropy $\\Delta\\epsilonelectric field, when electric field is approaching it's Frederiks threshold value $E\\Rightarrow E_{c}$. This means cancellation of the confinement effect found in Ref. [M.Vilfan et al. Phys.Rev.Lett. {\\bf 101}, 237801, (2008)] for dipole particles near the Frederiks transition while it remains for quadrupole particles. 2) New effect of \\textit{attraction and stabilization} of the particles along the electric field parallel to the cell planes in the homeotropic nematic cell with $\\Delta\\epsilon<0$ . The minimun distance between two particles depends on the strength of the field and can be ordinary for . 3) Attraction and repulsion zones for all elastic interactions are changed dramatically under the action of the external field.
V. G. Baryshevsky; A. A. Gurinovich
2005-06-14
In the present paper the equations for the spin evolution of a particle in a storage ring are analyzed considering contributions from the tensor electric and magnetic polarizabilities of the particle. Study of spin rotation and birefringence effect for a particle in a high energy storage ring provides for measurement as the real part of the coherent elastic zero-angle scattering amplitude as well as tensor electric and magnetic polarizabilities. We proposed the method for measurement the real part of the elastic coherent zero-angle scattering amplitude of particles and nuclei in a storage ring by the paramagnetic resonance in the periodical in time nuclear pseudoelectric and pseudomagnetic fields.
Quasi-magnetism of sterile dark matter with photonic portal
Wojciech Krolikowski
2008-05-06
We develop farther a simple model of cold dark matter consisting of sterile spin-1/2 fermions (sterinos), whose mass is generated by a nonzero vacuum expectation value of a field of sterile scalars (sterons). In this model, the sterile world of sterinos and sterons is conjectured to communicate with the familiar Standard Model world not only through gravity, but also through a photonic portal provided by a very weak effective interaction of the electromagnetic field with sterino and steron fields. Then, an extra, finite renormalization leading from the primary bare electric charge to a new bare electric charge appears spontaneously. Due to the photonic portal, the cold dark matter consisting of sterinos displays a phenomenon of quasi-magnetism, what means that it can interact effectively with cosmic (and laboratory) magnetic fields.
Hu, Ting; Dong, Jinming; Zhou, Jian; Kawazoe, Yoshiyuki
2014-08-14
The electronic and magnetic properties of armchair edge MoS{sub 2} nanoribbons (MoS{sub 2}-ANRs) underboth the external strain and transverse electric field (E{sub t}) have been systematically investigated by using the first-principles calculations. It is found that: (1) If no electric field is applied, an interesting structural phase transition would appear under a large tensile strain, leading to a new phase MoS{sub 2}-A'NR, and inducing a big jump peak of the band gap in the transition region. But, the band gap response to compressive strains is much different from that to tensile strain, showing no the structural phase transition. (2) Under the small tensile strains (<10%), the combined E{sub t} and tensile strain give rise to a positive superposition (resonant) effect on the band gap reduction at low E{sub t} (<3?V/nm), and oppositely a negative superposition (antiresonant) one at high E{sub t} (>4?V/nm). On the other hand, the external compressive strains have always presented the resonant effect on the band gap reduction, induced by the electric field. (3) After the structural phase transition, an external large tensile strain could greatly reduce the critical field E{sub tc} causing the band gap closure, and make the system become a ferromagnetic (FM) metal at a relative low E{sub t} (e.g., <4?V/nm), which is very helpful for its promising applications in nano-mechanical spintronics devices. (4) At high E{sub t} (>10?V/nm), the magnetic moments of both the MoS{sub 2}-ANR and MoS{sub 2}-A'NR in their FM states could be enhanced greatly by a tensile strain. Our numerical results of effectively tuning physical properties of MoS{sub 2}-ANRs by combined external strain and electric field may open their new potential applications in nanoelectronics and spintronics.
Chiral Gravity, Log Gravity and Extremal CFT
Alexander Maloney; Wei Song; Andrew Strominger
2009-03-26
We show that the linearization of all exact solutions of classical chiral gravity around the AdS3 vacuum have positive energy. Non-chiral and negative-energy solutions of the linearized equations are infrared divergent at second order, and so are removed from the spectrum. In other words, chirality is confined and the equations of motion have linearization instabilities. We prove that the only stationary, axially symmetric solutions of chiral gravity are BTZ black holes, which have positive energy. It is further shown that classical log gravity-- the theory with logarithmically relaxed boundary conditions --has finite asymptotic symmetry generators but is not chiral and hence may be dual at the quantum level to a logarithmic CFT. Moreover we show that log gravity contains chiral gravity within it as a decoupled charge superselection sector. We normally evaluate the Euclidean sum over geometries of chiral gravity and show that it gives precisely the holomorphic extremal CFT partition function. The modular invariance and integrality of the expansion coefficients of this partition function are consistent with the existence of an exact quantum theory of chiral gravity. We argue that the problem of quantizing chiral gravity is the holographic dual of the problem of constructing an extremal CFT, while quantizing log gravity is dual to the problem of constructing a logarithmic extremal CFT.
Foster, Jr., John S. (Pleasanton, CA); Wilson, James R. (Livermore, CA); McDonald, Jr., Charles A. (Danville, CA)
1983-01-01
1. In an electrical energy generator, the combination comprising a first elongated annular electrical current conductor having at least one bare surface extending longitudinally and facing radially inwards therein, a second elongated annular electrical current conductor disposed coaxially within said first conductor and having an outer bare surface area extending longitudinally and facing said bare surface of said first conductor, the contiguous coaxial areas of said first and second conductors defining an inductive element, means for applying an electrical current to at least one of said conductors for generating a magnetic field encompassing said inductive element, and explosive charge means disposed concentrically with respect to said conductors including at least the area of said inductive element, said explosive charge means including means disposed to initiate an explosive wave front in said explosive advancing longitudinally along said inductive element, said wave front being effective to progressively deform at least one of said conductors to bring said bare surfaces thereof into electrically conductive contact to progressively reduce the inductance of the inductive element defined by said conductors and transferring explosive energy to said magnetic field effective to generate an electrical potential between undeformed portions of said conductors ahead of said explosive wave front.
Using Electricity",,,"Electricity Consumption",,,"Electricity...
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. Total Electricity Consumption and Expenditures, 2003" ,"All Buildings* Using Electricity",,,"Electricity Consumption",,,"Electricity Expenditures" ,"Number of Buildings...
van Beek, Martijn; Dudarev, A
During the slow dump (discharge) of the Barrel Toroidal (superconducting) magnet of the ATLAS detector, the control system gave an alarm that the differences between the voltages over the conductors were too high. The alarm was not due to any danger, because of some sort of phenomenon observed in the first few seconds after start of the discharge. A possible explanation of the differences of the coil voltages is that the changing current through the conductors may cause induced currents in the coil casing around. The goal was to make a simulation of the electrical behaviour of the magnet system during a slow dump. In this way, an explanation can be found for the start phenomenon of the slow dump of the Barrel Toroid. Some extra analyses on the measurements were performed to describe the energy dissipation during a fast dump. This is done by calculating the resistance of the coils during the dump. With the maximum resistance, the maximum temperature can be estimated, which says something about the enthalpy of ...
Towards noncommutative gravity
D. V. Vassilevich
2009-02-17
In this short article accessible for non-experts I discuss possible ways of constructing a non-commutative gravity paying special attention to possibilities of realizing the full diffeomorphism symmetry and to relations with 2D gravities.
Ilyasov, V. V. E-mail: chuongnguyen11@gmail.com; Meshi, B. C.; Nguyen, V. C. E-mail: chuongnguyen11@gmail.com; Ershov, I. V.; Nguyen, D. C.
2014-07-07
The paper presents the results of ab initio study of the opportunities for tuning the band structure, magnetic and transport properties of zigzag graphene nanoribbon (8-ZGNR) on hexagonal boron nitride (h-BN(0001)) semiconductor heterostructure by transverse electric field (E{sub ext}). This study was performed within the framework of the density functional theory (DFT) using Grimme's (DFT-D2) scheme. We established the critical values of E{sub ext} for the 8-ZGNR/h-BN(0001) heterostructure, thereby providing for semiconductor-halfmetal transition in one of electron spin configurations. This study also showed that the degeneration in energy of the localized edge states is removed when E{sub ext} is applied. In ZGNR/h-BN (0001) heterostructure, value of the splitting energy was higher than one in ZGNRs without substrate. We determined the effect of low E{sub ext} applied to the 8-ZGNR/h-BN (0001) semiconductor heterostructure on the preserved local magnetic moment (LMM) (0.3?{sub B}) of edge carbon atoms. The transport properties of the 8-ZGNR/h-BN(0001) semiconductor heterostructure can be controlled using E{sub ext}. In particular, at a critical value of the positive potential, the electron mobility can increase to 7× 10{sup 5} cm{sup 2}/V?s or remain at zero in the spin-up and spin-down electron subsystems, respectively. We established that magnetic moments (MMs), band gaps, and carrier mobility can be altered using E{sub ext}. These abilities enable the use of 8-ZGNR/h-BN(0001) semiconductor heterostructure in spintronics.
Rong-Jia Yang
2014-09-11
If we assume that the source of thermodynamic system, $\\rho$ and $p$, are also the source of gravity, thermal quantities, such as entropy, temperature, and chemical potential, can induce effects of gravity, or gravity can induce thermal effects. We find only for systems with constant temperature and zero chemical potential, gravity can be seen as an entropic force. The case for Newtonian approximation is discussed.
Karim Noui
2010-03-31
We tackle the question of motion in Quantum Gravity: what does motion mean at the Planck scale? Although we are still far from a complete answer we consider here a toy model in which the problem can be formulated and resolved precisely. The setting of the toy model is three dimensional Euclidean gravity. Before studying the model in detail, we argue that Loop Quantum Gravity may provide a very useful approach when discussing the question of motion in Quantum Gravity.
Terrestrial Gravity Fluctuations
Jan Harms
2015-07-21
The article reviews the current state of the field, and also presents new analyses especially with respect to the impact of seismic scattering on gravity perturbations, active gravity noise cancellation, and time-domain models of gravity perturbations from atmospheric and seismic point sources. Our understanding of terrestrial gravity fluctuations will have great impact on the future development of GW detectors and high-precision gravimetry in general, and many open questions need to be answered still as emphasized in this article.
Stephen Hawking Quantum Gravity
Visser, Matt
Stephen Hawking and Quantum Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 4 Nov 2000 #12; Stephen Hawking and Quantum Gravity Abstract: Through research, Stephen Hawking has captured a place in the popular imagina- tion. Quantum gravity in its various
Quantum Physics Einstein's Gravity
Visser, Matt
Quantum Physics confronts Einstein's Gravity Matt Visser Physics Department Washington University Saint Louis USA Science Saturdays 13 October 2001 #12; Quantum Physics confronts Einstein's Gravity and with Einstein's theory of gravity (the general relativity) is still the single biggest theoretical problem
Li, Hao-Ze; Liu, Hai-Tao Liu, Zhen-Yu Lu, Hui-Hu; Song, Hong-Yu; Wang, Guo-Dong
2014-02-15
An Fe-6.5 wt.% Si-0.3 wt.% Al as-cast sheet was produced by twin-roll strip casting process, then treated with hot rolling, warm rolling and annealing. A detailed study of the microstructure and texture evolution at different processing stages was carried out by optical microscopy, X-ray diffraction and electron backscattered diffraction analysis. The initial as-cast strip showed strong columnar grains and pronounced < 001 >//ND texture. The hot rolled and warm rolled sheets were characterized by large amounts of shear bands distributed through the thickness together with strong < 110 >//RD texture and weak < 111 >//ND texture. After annealing, detrimental < 111 >//ND texture almost disappeared while beneficial (001)<210 >, (001)<010 >, (115)<5 ? 10 1 > and (410) < 001 > recrystallization textures were formed, thus the magnetic induction of the annealed sheet was significantly improved. The recrystallization texture in the present study could be explained by preferred nucleation and grain growth mechanism. - Highlights: • A high silicon as-cast strip with columnar structure was produced. • A thin warm rolled sheet without large edge cracks was obtained. • Microstructure and texture evolution at each stage were investigated. • Beneficial (001)<210 >, (001)<010 >, (410)<001 > recrystallization textures were formed. • The magnetic induction of annealed sheet was significantly improved.
Zhang, Yue Wang, Zhiguang; Wang, Yaojin; Luo, Chengtao; Li, Jiefang; Viehland, Dwight
2014-02-28
Magnetostrictive Fe-Ga thin layers were deposited on ?110?-oriented Pb(Mg{sub 1/3}Nb{sub 2/3})-30%PbTiO{sub 3} (PMN-30%PT) substrates by pulsed laser deposition. The as-prepared heterostructures showed columnar arrays aligned in the out-of-plane direction. Transmission electron microscopy revealed nanocrystalline regions within the columnar arrays of the Fe-Ga film. The heterostructure exhibited a strong converse magnetoelectric coupling effect of up to 4.55?×?10{sup ?7} s m{sup ?1}, as well as an electric field tunability of the in-plane magnetic anisotropy. Furthermore, the remanent magnetization states of the Fe-Ga films can be reversibly and irreversibly changed by external electric fields, suggesting a promising and robust application in magnetic random access memories and spintronics.
Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...
Office of Scientific and Technical Information (OSTI)
Warburton, E. K. PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...
Magnetic Pair Spectrometer Studies of Electromagnetic Transitions...
Office of Scientific and Technical Information (OSTI)
English Subject: PHYSICS; BRANCHING RATIO; CARBON 13; CARBON 14; DECAY; DEUTERON BEAMS; ELECTRIC CHARGES; ENERGY; ENERGY LEVELS; ERRORS; LIFETIME; MAGNETIC FIELDS; MAGNETIC...
Quantization of Emergent Gravity
Hyun Seok Yang
2014-12-24
Emergent gravity is based on a novel form of the equivalence principle known as the Darboux theorem or the Moser lemma in symplectic geometry stating that the electromagnetic force can always be eliminated by a local coordinate transformation as far as spacetime admits a symplectic structure, in other words, a microscopic spacetime becomes noncommutative (NC). If gravity emerges from U(1) gauge theory on NC spacetime, this picture of emergent gravity suggests a completely new quantization scheme where quantum gravity is defined by quantizing spacetime itself, leading to a dynamical NC spacetime. Therefore the quantization of emergent gravity is radically different from the conventional approach trying to quantize a phase space of metric fields. This approach for quantum gravity allows a background independent formulation where spacetime as well as matter fields is equally emergent from a universal vacuum of quantum gravity.
Ground Magnetics At San Francisco Volcanic Field Area (Warpinski...
geologically mapped the target area, obtained rock samples for age dating and mineral chemistry, performed gravity and magnetic surveys, and integrated these results to identify...
Solid Holography and Massive Gravity
Alberte, Lasma; Khmelnitsky, Andrei; Pujolas, Oriol
2015-01-01
Momentum dissipation is an important ingredient in condensed matter physics that requires a translation breaking sector. In the bottom-up gauge/gravity duality, this implies that the gravity dual is massive. We start here a systematic analysis of holographic massive gravity (HMG) theories, which admit field theory dual interpretations and which, therefore, might store interesting condensed matter applications. We show that there are many phases of HMG that are fully consistent effective field theories and which have been left overlooked in the literature. The most important distinction between the different HMG phases is that they can be clearly separated into solids and fluids. This can be done both at the level of the unbroken spacetime symmetries as well as concerning the elastic properties of the dual materials. We extract the modulus of rigidity of the solid HMG black brane solutions and show how it relates to the graviton mass term. We also consider the implications of the different HMGs on the electric...
Advanced Integrated Electric Traction System
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Integrated Electric Traction System Greg S. Smith Email: gregory.3.smith@gm.com Phone: (310) 257-3812 Organization: General Motors Team members: Ames Laboratory Arnold Magnetics...
Liu, Y.; Bose, S. K.; Kudrnovský, J.
2013-12-07
This work presents results for the electronic structure, magnetic properties, and electrical resistivity of the semiconductor SnTe doped with 3d transition metals V and Cr. From the standpoint of potential application in spintronics, we look for half-metallic states and analyze their properties in both rock salt and zinc blende structures using ab initio electronic structure methods. In both cases, it is the Sn-sublattice that is doped with the transition metals, as has been the case with experiments performed so far. We find four half-metallic compounds at their optimized cell volumes. Results of exchange interactions and the Curie temperature are presented and analyzed for all the relevant cases. Resistivity calculation based on Kubo-Greenwood formalism shows that the resistivities of these alloys due to transition metal doping of the Sn-sublattice may vary, in most cases, from typical liquid metal or metallic glass value to 2–3 times higher. 25% V-doping of the Sn-sublattice in the rock salt structure gives a very high resistivity, which can be traced to high values of the lattice parameter resulting in drastically reduced hopping or diffusivity of the states at the Fermi level.
F. Henry-Couannier; A. Tilquin; C. Tao; A. Ealet
2007-10-24
The previous version of this article was a first attempt to confront the Dark Gravity theory to cosmological data. However, more recent developments lead to the conclusion that the cosmological principle is probably not valid in Dark Gravity so that this kind of analysis is at best very premature. A more recent and living review of the Dark Gravity theory can be found in gr-qc/0610079
Thermoacoustic magnetohydrodynamic electrical generator
Wheatley, J.C.; Swift, G.W.; Migliori, A.
1986-07-08
A thermoacoustic magnetohydrodynamic electrical generator is described comprising a magnet having a magnetic field, an elongate hollow housing containing an electrically conductive liquid and a thermoacoustic structure positioned in the liquid, heat exchange means thermally connected to the thermoacoustic structure for inducing the liquid to oscillate at an acoustic resonant frequency within the housing. The housing is positioned in the magnetic field and oriented such that the direction of the magnetic field and the direction of oscillatory motion of the liquid are substantially orthogonal to one another, first and second electrical conductor means connected to the liquid on opposite sides of the housing along an axis which is substantially orthogonal to both the direction of the magnetic field and the direction of oscillatory motion of the liquid, an alternating current output signal is generated in the conductor means at a frequency corresponding to the frequency of the oscillatory motion of the liquid.
Felix M. Lev
2010-05-16
We consider a possibility that gravity is not an interaction but a manifestation of a symmetry based on a Galois field.
Using Electricity",,,"Electricity Consumption",,,"Electricity...
U.S. Energy Information Administration (EIA) Indexed Site
A. Total Electricity Consumption and Expenditures for All Buildings, 2003" ,"All Buildings Using Electricity",,,"Electricity Consumption",,,"Electricity Expenditures" ,"Number of...
Electricity",,,"Electricity Consumption",,,"Electricity Expenditures...
U.S. Energy Information Administration (EIA) Indexed Site
C9. Total Electricity Consumption and Expenditures, 1999" ,"All Buildings Using Electricity",,,"Electricity Consumption",,,"Electricity Expenditures" ,"Number of Buildings...
Electricity",,,"Electricity Consumption",,,"Electricity Expenditures...
U.S. Energy Information Administration (EIA) Indexed Site
DIV. Total Electricity Consumption and Expenditures by Census Division, 1999" ,"All Buildings Using Electricity",,,"Electricity Consumption",,,"Electricity Expenditures" ,"Number...
Emergent gravity requires kinematic nonlocality
Marolf, D
2015-01-01
Saueressig, Quantum Einstein Gravity, New J.Phys. 14 (2012)T. Matsuki, and H. Terazawa, Gravity and Electromagnetism asat a lattice formulation of gravity, . http://cds.cern.ch/
Quantum gravity on the lattice
Hamber, Herbert W.
2009-01-01
the Conference Quantum Gravity: Challenges and Perspectives.divergences in quantum gravity. In: Hawking, S.W. , Israel,f ) V n?1 ( f ) = Quantum gravity on the lattice Similarly,
Thermoelectric Conductivities at Finite Magnetic Field and the Nernst Effect
Keun-Young Kim; Kyung Kiu Kim; Yunseok Seo; Sang-Jin Sin
2015-08-24
We study the thermoelectric conductivities of a strongly correlated system in the presence of a magnetic field by the gauge/gravity duality. We consider a class of Einstein-Maxwell-Dilaton theories with axion fields imposing momentum relaxation. General analytic formulas for the direct current(DC) conductivities and the Nernst signal are derived in terms of the black hole horizon data. For an explicit model study, we analyse in detail the dyonic black hole modified by momentum relaxation. In this model, for small momentum relaxation, the Nernst signal shows a bell-shaped dependence on the magnetic field, which is a feature of the normal phase of cuprates. We compute all alternating current(AC) electric, thermoelectric, and thermal conductivities by numerical analysis and confirm that their zero frequency limits precisely reproduce our analytic DC formulas, which is a non-trivial consistency check of our methods. We discuss the momentum relaxation effects on the conductivities including cyclotron resonance poles.
Thermoacoustic magnetohydrodynamic electrical generator
Wheatley, J.C.; Swift, G.W.; Migliori, A.
1984-11-16
A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.
Thermoacoustic magnetohydrodynamic electrical generator
Wheatley, John C. (Los Alamos, NM); Swift, Gregory W. (Los Alamos, NM); Migliori, Albert (Santa Fe, NM)
1986-01-01
A thermoacoustic magnetohydrodynamic electrical generator includes an intrinsically irreversible thermoacoustic heat engine coupled to a magnetohydrodynamic electrical generator. The heat engine includes an electrically conductive liquid metal as the working fluid and includes two heat exchange and thermoacoustic structure assemblies which drive the liquid in a push-pull arrangement to cause the liquid metal to oscillate at a resonant acoustic frequency on the order of 1,000 Hz. The engine is positioned in the field of a magnet and is oriented such that the liquid metal oscillates in a direction orthogonal to the field of the magnet, whereby an alternating electrical potential is generated in the liquid metal. Low-loss, low-inductance electrical conductors electrically connected to opposite sides of the liquid metal conduct an output signal to a transformer adapted to convert the low-voltage, high-current output signal to a more usable higher voltage, lower current signal.
Lensless Imaging of Magnetic Nanostructures
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
28 March 2012 00:00 Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying...
Thermoelectric Conductivities at Finite Magnetic Field and the Nernst Effect
Kim, Keun-Young; Seo, Yunseok; Sin, Sang-Jin
2015-01-01
We study electric, thermoelectric, and thermal conductivities of a strongly correlated system in the presence of magnetic field by gauge/gravity duality. We consider a general class of Einstein-Maxwell-Dilaton theory with axion fields imposing momentum relaxation. Analytic general formulas for DC conductivities and the Nernst signal are derived in terms of the black hole horizon data. For an explicit model study we analyse in detail the Dyonic black hole modified by momentum relaxation effect. In this model, the Nernst signal shows a typical vortex-liquid effect when momentum relaxation effect is comparable to chemical potential. We compute all AC electric, thermal, and thermal conductivities by numerical analysis and confirms that their zero frequency limits precisely reproduce our analytic formulas, which is a non-trivial consistency check of our methods. We discuss the momentum relaxation effect on conductivities including cyclotron frequencies.
Topics in Nonsupersymmetric Scattering Amplitudes in Gauge and Gravity Theories
Nohle, Joshua David
2015-01-01
Gravity . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .Ultraviolet Properties of Gravity . . . . . . .Kinematics Duality and Gravity as a Double Copy of Yang-
Probability around the Quantum Gravity. Part 1: Planar Pure Gravity
Probability around the Quantum Gravity. Part 1: Planar Pure Gravity V.A.Malyshev \\Lambda September 17, 1998 Abstract In this paper we study stochastic dynamics which leaves quantum gravity equilibrium science and biology. At the same time the paper can serve an intro duction to quantum gravity
Mi, Chunting "Chris"
for predicting iron losses and improving energy efficiency in electrical machines and transformers. Prediction of Electrical Machines and Transformers Operated by Pulsewidth-Modulated Inverters Ruifang Liu1;2, Chris) inverters are used more and more to operate electrical machines and to interface renewable energy systems
Zygmunt Lalak; Stefan Pokorski; Krzysztof Turzynski
2008-08-18
We investigate O'Raifeartaigh-type models for F-term supersymmetry breaking in gauge mediation scenarios in the presence of gravity. It is pointed out that the vacuum structure of those models is such that in metastable vacua gravity mediation contribution to scalar masses is always suppressed to the level below 1 percent, almost sufficient for avoiding FCNC problem. Close to that limit, gravitino mass can be in the range 10-100 GeV, opening several interesting possibilities for gauge mediation models, including Giudice-Masiero mechanism for mu and Bmu generation. Gravity sector can include stabilized moduli.
Electric and Magnetic Fields Facts
2006-08-01
This discussion outlines the EMF issue, summarizes the research conducted to date, and describes what Western Area Power Administration is doing to address concerns about EMF.
Hong, Yang-Ki; Haskew, Timothy; Myryasov, Oleg; Jin, Sungho; Berkowitz, Ami
2014-06-05
The research we conducted focuses on the rare-earth (RE)-free permanent magnet by modeling, simulating, and synthesizing exchange coupled two-phase (hard/soft) RE-free core-shell nano-structured magnet. The RE-free magnets are made of magnetically hard core materials (high anisotropy materials including Mn-Bi-X and M-type hexaferrite) coated by soft shell materials (high magnetization materials including Fe-Co or Co). Therefore, our research helps understand the exchange coupling conditions of the core/shell magnets, interface exchange behavior between core and shell materials, formation mechanism of core/shell structures, stability conditions of core and shell materials, etc.
Shan Gao
2011-07-16
It is argued that the existence of a minimum size of spacetime may imply the fundamental existence of gravity as a geometric property of spacetime described by general relativity.
Francis J. M. Farley
2015-08-14
In the muon storage rings the muons are subject to a very large radial acceleration. The equivalence principle implies a large gravity force. It has no effect on the muon lifetime.
Exercise in artificial gravity
Edmonds, Jessica Leigh
2005-01-01
Artificial gravity provided by short radius centrifugation is considered a promising countermeasure to the deleterious physiological effects of microgravity during long-duration space flight. We investigated the feasibility ...
Commonwealth Associates, Inc.; IIT Research Institute
1997-08-01
This draft report consists of two volumes. Volume 1, the main body, contains an introducto~ sectionj an overview of magnetic fields sectio~ and field reduction technology evaluation section. Magnetic field reduction methods are evalpated for transmission lines, distribution Iines,sulxtations, building wiring applkmd machinery, and transportation systems. The evaluation considers effectiveness, co% and other ftiors. Volume 2 contains five appendices, Append~ A presents magnetic field shielding information. Appendices B and C present design assumptions and magnetic field plots for transmission and distribution lines, respectively. Appendices D and E present cost estimate details for transmission and distribution limes, respectively.
Bertotti-Robinson type solutions to Dilaton-Axion Gravity
Gerard Clement; Dmitri Gal'tsov
2001-02-06
We present a new solution to dilaton-axion gravity which looks like a rotating Bertotti-Robinson (BR) Universe. It is supported by an homogeneous Maxwell field and a linear axion and can be obtained as a near-horizon limit of extremal rotating dilaton-axion black holes. It has the isometry $SL(2,R)\\times U(1)$ where U(1) is the remnant of the SO(3) symmetry of BR broken by rotation, while $SL(2,R)$ corresponds to the $AdS_2$ sector which no longer factors out of the full spacetime. Alternatively our solution can be obtained from the D=5 vacuum counterpart to the dyonic BR with equal electric and magnetic field strengths. The derivation amounts to smearing it in D=6 and then reducing to D=4 with dualization of one Kaluza-Klein two-form in D=5 to produce an axion. Using a similar dualization procedure, the rotating BR solution is uplifted to D=11 supergravity. We show that it breaks all supersymmetries of N=4 supergravity in D=4, and that its higher dimensional embeddings are not supersymmetric either. But, hopefully it may provide a new arena for corformal mechanics and holography. Applying a complex coordinate transformation we also derive a BR solution endowed with a NUT parameter.
Bertotti-Robinson type solutions to Dilaton-Axion Gravity
Clément, G; Clement, Gerard; Gal'tsov, Dmitri
2001-01-01
We present a new solution to dilaton-axion gravity which looks like a rotating Bertotti-Robinson (BR) Universe. It is supported by an homogeneous Maxwell field and a linear axion and can be obtained as a near-horizon limit of extremal rotating dilaton-axion black holes. It has the isometry $SL(2,R)\\times U(1)$ where U(1) is the remnant of the SO(3) symmetry of BR broken by rotation, while $SL(2,R)$ corresponds to the $AdS_2$ sector which no longer factors out of the full spacetime. Alternatively our solution can be obtained from the D=5 vacuum counterpart to the dyonic BR with equal electric and magnetic field strengths. The derivation amounts to smearing it in D=6 and then reducing to D=4 with dualization of one Kaluza-Klein two-form in D=5 to produce an axion. Using a similar dualization procedure, the rotating BR solution is uplifted to D=11 supergravity. We show that it breaks all supersymmetries of N=4 supergravity in D=4, and that its higher dimensional embeddings are not supersymmetric either. But, hop...
Gravity-driven intrusions in stratified fluids
Maurer, Benjamin Dudley
2011-01-01
5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6partial- depth intrusive gravity currents,” Atmosphere -
Magnetic switch coupling to synchronize magnetic modulators
Reed, Kim W. (Albuquerque, NM); Kiekel, Paul (Albuquerque, NM)
1999-01-01
Apparatus for synchronizing the output pulses from a pair of magnetic switches. An electrically conductive loop is provided between the pair of switches with the loop having windlings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself.
Magnetic switch coupling to synchronize magnetic modulators
Reed, K.W.; Kiekel, P.
1999-04-27
Apparatus for synchronizing the output pulses from a pair of magnetic switches is disclosed. An electrically conductive loop is provided between the pair of switches with the loop having windings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself. 13 figs.
Ground Magnetics At Neal Hot Springs Geothermal Area (U.S. Geothermal...
Date 2007 - 2007 Usefulness not indicated DOE-funding Unknown Exploration Basis Gravity and Magnetic surveys were done as part of U.S. Geothermal's geophysical program for...
B. S. Schlimme; P. Achenbach; C. A. Ayerbe Gayoso; J. C. Bernauer; R. Böhm; D. Bosnar; Th. Challand; M. O. Distler; L. Doria; F. Fellenberger; H. Fonvieille; M. Gómez Rodríguez; P. Grabmayr; T. Hehl; W. Heil; D. Kiselev; J. Krimmer; M. Makek; H. Merkel; D. G. Middleton; U. Müller; L. Nungesser; B. A. Ott; J. Pochodzalla; M. Potokar; S. Sánchez Majos; M. M. Sargsian; I. Sick; S. Širca; M. Weinriefer; M. Wendel; C. J. Yoon
2013-08-29
A measurement of beam helicity asymmetries in the reaction 3He(e,e'n)pp has been performed at the Mainz Microtron in quasielastic kinematics in order to determine the electric to magnetic form factor ratio of the neutron, GEn/GMn, at a four momentum transfer Q2 = 1.58 GeV2. Longitudinally polarized electrons were scattered on a highly polarized 3He gas target. The scattered electrons were detected with a high-resolution magnetic spectrometer, and the ejected neutrons with a dedicated neutron detector composed of scintillator bars. To reduce systematic errors data were taken for four different target polarization orientations allowing the determination of GEn/GMn from a double ratio. We find mu_n GEn/GMn = 0.250 +/- 0.058(stat.) +/- 0.017 (sys.).
Magnetic polarizability of the nucleon
Ragusa, S.
1996-01-01
We derive an expression for the magnetic polarizability of the nucleon, as related to sums of products of its electromagnetic transition moments involving the electric and magnetic dipoles and mean-square radii, as well as the electric quadrupole moment. Two sum rules emerge from the calculation. {copyright} {ital 1995 The American Physical Society.}
Extreme neutron stars from Extended Theories of Gravity
Astashenok, Artyom V.; Capozziello, Salvatore; Odintsov, Sergei D. E-mail: capozziello@na.infn.it
2015-01-01
We discuss neutron stars with strong magnetic mean fields in the framework of Extended Theories of Gravity. In particular, we take into account models derived from f(R) and f(G) extensions of General Relativity where functions of the Ricci curvature invariant R and the Gauss-Bonnet invariant G are respectively considered. Dense matter in magnetic mean field, generated by magnetic properties of particles, is described by assuming a model with three meson fields and baryons octet. As result, the considerable increasing of maximal mass of neutron stars can be achieved by cubic corrections in f(R) gravity. In principle, massive stars with M > 4M{sub ?} can be obtained. On the other hand, stable stars with high strangeness fraction (with central densities ?{sub c} ? 1.5–2.0 GeV/fm{sup 3}) are possible considering quadratic corrections of f(G) gravity. The magnetic field strength in the star center is of order 6–8 × 10{sup 18} G. In general, we can say that other branches of massive neutron stars are possible considering the extra pressure contributions coming from gravity extensions. Such a feature can constitute both a probe for alternative theories and a way out to address anomalous self-gravitating compact systems.
Potential Energy and the Body Electric
Helmreich, Stefan
Physics tells us that potential energy is the capacity to do work that a body possesses as a result of its position in electric, magnetic, or gravitational fields. Thinking of “potentiality” in an electric idiom and with ...
On the no-gravity limit of gravity
J. Kowalski-Glikman; M. Szczachor
2012-12-21
We argue that Relative Locality may arise in the no gravity $G\\rightarrow0$ limit of gravity. In this limit gravity becomes a topological field theory of the BF type that, after coupling to particles, may effectively deform its dynamics. We briefly discuss another no gravity limit with a self dual ground state as well as the topological ultra strong $G\\rightarrow\\infty$ one.
Post-Newtonian, Quasi-Circular Binary Inspirals in Quadratic Modified Gravity
Kent Yagi; Leo C. Stein; Nicolas Yunes; Takahiro Tanaka
2012-04-16
We consider a general class of quantum gravity-inspired, modified gravity theories, where the Einstein-Hilbert action is extended through the addition of all terms quadratic in the curvature tensor coupled to scalar fields with standard kinetic energy. This class of theories includes Einstein-Dilaton-Gauss-Bonnet and Chern-Simons modified gravity as special cases. We analytically derive and solve the coupled field equations in the post-Newtonian approximation, assuming a comparable-mass, spinning black hole binary source in a quasi-circular, weak-field/slow-motion orbit. We find that a naive subtraction of divergent piece associated with the point-particle approximation is ill-suited to represent compact objects in these theories. Instead, we model them by appropriate effective sources built so that known strong-field solutions are reproduced in the far-field limit. In doing so, we prove that black holes in Einstein-Dilaton-Gauss-Bonnet and Chern-Simons theory can have hair, while neutron stars have no scalar monopole charge, in diametrical opposition to results in scalar-tensor theories. We then employ techniques similar to the direct integration of the relaxed Einstein equations to obtain analytic expressions for the scalar field, metric perturbation, and the associated gravitational wave luminosity measured at infinity. We find that scalar field emission mainly dominates the energy flux budget, sourcing electric-type (even-parity) dipole scalar radiation and magnetic-type (odd-parity) quadrupole scalar radiation, correcting the General Relativistic prediction at relative -1PN and 2PN orders. Such modifications lead to corrections in the emitted gravitational waves that can be mapped to the parameterized post-Einsteinian framework. Such modifications could be strongly constrained with gravitational wave observations.
Polchinski, Joseph [Kavli Institute for Theoretical Physics
2010-09-01
Gauge theories, which describe the particle interactions, are well understood, while quantum gravity leads to many puzzles. Remarkably, in recent years we have learned that these are actually dual, the same system written in different variables. On the one hand, this provides our most precise description of quantum gravity, resolves some long-standing paradoxes, and points to new principles. On the other, it gives a new perspective on strong interactions, with surprising connections to other areas of physics. I describe these ideas, and discuss current and future directions.
B. V. Vasiliev
2010-09-05
It is shown that the gravity-induced electric polarization of intrastellar plasma must be taken into consideration at formulation of a star theory, as plasma in the stars is electrically polarized.
Light, Max E; Colestock, Patrick L
2014-01-28
An electron cyclotron resonance (ECR) thruster is disclosed having a plasma chamber which is electrically biased with a positive voltage. The chamber bias serves to efficiently accelerate and expel the positive ions from the chamber. Electrons follow the exiting ions, serving to provide an electrically neutral exhaust plume. In a further embodiment, a downstream shaping magnetic field serves to further accelerate and/or shape the exhaust plume.
Goodman, Ronald K. (Livermore, CA); Hunt, Angus L. (Alamo, CA)
1984-01-01
Electrically chargeable laser targets and method for forming such charged targets in order to improve their guidance along a predetermined desired trajectory. This is accomplished by the incorporation of a small amount of an additive to the target material which will increase the electrical conductivity thereof, and thereby enhance the charge placed upon the target material for guidance thereof by electrostatic or magnetic steering mechanisms, without adversely affecting the target when illuminated by laser energy.
Introduction Basics of gravity theory
Visser, Matt
Introduction Basics of gravity theory Actions and Field Equations Phenomenology Discussion;Introduction Basics of gravity theory Actions and Field Equations Phenomenology Discussion and Conclusions Victoria U of Wellington - Feb 2nd 2009 #12;Introduction Basics of gravity theory Actions and Field
Loop quantum gravity and observations
A. Barrau; J. Grain
2015-10-28
Quantum gravity has long been thought to be completely decoupled from experiments or observations. Although it is true that smoking guns are still missing, there are now serious hopes that quantum gravity phenomena might be tested. We review here some possible ways to observe loop quantum gravity effects either in the framework of cosmology or in astroparticle physics.
Even-dimensional topological gravity from Chern-Simons gravity
Nelson Merino; Alfredo Perez; Patricio Salgado
2009-10-08
It is shown that the topological action for gravity in 2n-dimensions can be obtained from the 2n+1-dimensional Chern-Simons gravity genuinely invariant under the Poincare group. The 2n-dimensional topological gravity is described by the dynamics of the boundary of a 2n+1-dimensional Chern-Simons gravity theory with suitable boundary conditions. The field $\\phi^{a}$, which is necessary to construct this type of topological gravity in even dimensions, is identified with the coset field associated with the non-linear realizations of the Poincare group ISO(d-1,1).
From Classical To Quantum Gravity: Introduction to Loop Quantum Gravity
Kristina Giesel; Hanno Sahlmann
2013-01-02
We present an introduction to the canonical quantization of gravity performed in loop quantum gravity, based on lectures held at the 3rd quantum geometry and quantum gravity school in Zakopane in 2011. A special feature of this introduction is the inclusion of new proposals for coupling matter to gravity that can be used to deparametrize the theory, thus making its dynamics more tractable. The classical and quantum aspects of these new proposals are explained alongside the standard quantization of vacuum general relativity in loop quantum gravity.
Massive gravity as a limit of bimetric gravity
Martin-Moruno, Prado; Visser, Matt
2013-01-01
Massive gravity may be viewed as a suitable limit of bimetric gravity. The limiting procedure can lead to an interesting interplay between the "background" and "foreground" metrics in a cosmological context. The fact that in bimetric theories one always has two sets of metric equations of motion continues to have an effect even in the massive gravity limit. Thus, solutions of bimetric gravity in the limit of vanishing kinetic term are also solutions of massive gravity, but the contrary statement is not necessarily true.
Quantum Gravity and Turbulence
Vishnu Jejjala; Djordje Minic; Y. Jack Ng; Chia-Hsiung Tze
2010-05-18
We apply recent advances in quantum gravity to the problem of turbulence. Adopting the AdS/CFT approach we propose a string theory of turbulence that explains the Kolmogorov scaling in 3+1 dimensions and the Kraichnan and Kolmogorov scalings in 2+1 dimensions. In the gravitational context, turbulence is intimately related to the properties of spacetime, or quantum, foam.
Christian Wiesendanger
2009-07-25
Isometrodynamics (ID), the gauge theory of the group of volume-preserving diffeomorphisms of an "inner" D-dimensional flat space, is tentatively interpreted as a fundamental theory of gravity. Dimensional analysis shows that the Planck length l_P - and through it \\hbar and \\Gamma - enters the gauge field action linking ID and gravity in a natural way. Noting that the ID gauge field couples solely through derivatives acting on "inner" space variables all ID fields are Taylor-expanded in "inner" space. Integrating out the "inner" space variables yields an effective field theory for the coefficient fields with l_P^2 emerging as the expansion parameter. For \\hbar goint to zero only the leading order field does not vanish. This classical field couples to the matter Noether currents and charges related to the translation invariance in "inner" space. A model coupling this leading order field to a matter point source is established and solved. Interpreting the matter Noether charge in terms of gravitational mass Newton's inverse square law is finally derived for a static gauge field source and a slowly moving test particle. Gravity emerges as potentially related to field variations over "inner" space and might microscopically be described by the ID gauge field or equivalently by an infinite string of coefficient fields only the leading term of which is related to the macroscopical effects of gravity.
Plated lamination structures for integrated magnetic devices
Webb, Bucknell C.
2014-06-17
Semiconductor integrated magnetic devices such as inductors, transformers, etc., having laminated magnetic-insulator stack structures are provided, wherein the laminated magnetic-insulator stack structures are formed using electroplating techniques. For example, an integrated laminated magnetic device includes a multilayer stack structure having alternating magnetic and insulating layers formed on a substrate, wherein each magnetic layer in the multilayer stack structure is separated from another magnetic layer in the multilayer stack structure by an insulating layer, and a local shorting structure to electrically connect each magnetic layer in the multilayer stack structure to an underlying magnetic layer in the multilayer stack structure to facilitate electroplating of the magnetic layers using an underlying conductive layer (magnetic or seed layer) in the stack as an electrical cathode/anode for each electroplated magnetic layer in the stack structure.
Irrotational-fluid cosmologies in fourth-order gravity
Amare Abebe; Maye Elmardi
2015-04-25
In this paper, we explore classes of irrotational-fluid cosmological models in the context of f(R)-gravity in an attempt to put some theoretical and mathematical restrictions on the form of the f(R) gravitational Lagrangian. In particular, we investigate the consistency of linearised dust models for shear-free cases as well as in the limiting cases when either the gravito-magnetic or gravito-elecric components of the Weyl tensor vanish. We also discuss the existence and consistency of classes of non-expanding irrotational spacetimes in f(R)-gravity.
Radiations from Oscillating Axionic Boson Stars in an External Magnetic Field
Aiichi Iwazaki
1998-04-23
We solve numerically a field equation of axions coupled with gravity and show solutions representing oscillating axionic boson stars with small mass $\\sim 10^{-12}M_{\\odot}$ and large radius $\\sim 10^{8}$ cm. We present explicitly a relation between the mass and the radius of the boson stars with such a small mass. These axionic boson stars are shown to possess oscillating electric currents in an external magnetic field and to radiate electromagnetic fields with a frequency given by mass of the axions. We estimate the luminosity of the radiation in a strong magnetic field $10^{12}$G of neutron stars, typically $\\sim 10^{24}$ erg/s with the axion mass being $10^{-5}$eV.
Mi, Chunting "Chris"
IEEE TRANSACTIONS ON MAGNETICS, VOL. 44, NO. 8, AUGUST 2008 2021 Modeling of Eddy-Current Loss and transformers operated by PWM inverters. These losses are primarily attributed to eddy-current loss caused the effects of different parameters of PWM switching on the eddy-current loss. We compare the iron losses
California at Berkeley, University of
OBSERVATIONS OF THE STRUCTURE OF STANDING WAVES IN THE MAGNETOSPHERE L. J. Cahill, Jr., 1N. G. Lin,1, 2 M. J 1 spacecraft provided observations of toroidal standing wave oscilla- tions of magnetic shells the standing wave periods calculated were reasonably close to, but somewhat less than, the observed periods
Generic magnetic fusion reactor cost assessment
Sheffield, J.
1984-01-01
A generic D-T burning magnetic fusion reactor model shows that within the constraints set by generic limitations it is possible for magnetic fusion to be a competitive source of electricity in the 21st century.
Prigozhin, Leonid
London, London SW7 2AZ, UK 2 Department of Solar Energy and Environmental Physics, Blaustein Institutes all variables of interest, including the electric field, for any value of the power in the power law currentvoltage relation characterizing the superconducting material. For high power values we obtain
R. Bluhm
2013-07-22
Gravitational theories with Lorentz violation must account for a number of possible features in order to be consistent theoretically and phenomenologically. A brief summary of these features is given here. They include evasion of a no-go theorem, connections between spontaneous Lorentz breaking and diffeomorphism breaking, the appearance of massless Nambu-Goldstone modes and massive Higgs modes, and the possibility of a Higgs mechanism in gravity.
Gravity, Dimension, Equilibrium, & Thermodynamics
Jerome Perez
2006-03-30
Is it actually possible to interpret gravitation as space's property in a pure classical way. Then, we note that extended self-gravitating system equilibrium depends directly on the number of dimension of the space in which it evolves. Given those precisions, we review the principal thermodynamical knowledge in the context of classical gravity with arbitrary dimension of space. Stability analyses for bounded 3D systems, namely the Antonov instability paradigm, are then rapproched to some amazing properties of globular clusters and galaxies.
Massive Gravity from Higher Derivative Gravity with Boundary Conditions
Minjoon Park; Lorenzo Sorbo
2012-10-29
With an appropriate choice of parameters, a higher derivative theory of gravity can describe a normal massive sector and a ghost massless sector. We show that, when defined on an asymptotically de Sitter spacetime with Dirichlet boundary conditions, such a higher derivative gravity can provide a framework for a unitary theory of massive gravity in four spacetime dimensions. The resulting theory is free not only of higher derivative ghosts but also of the Boulware-Deser mode.
Marcus S. Cohen
2002-08-02
Quantum gravity has been so elusive because we have tried to approach it by two paths which can never meet: quantum mechanics and general relativity. These contradict each other not only in superdense regimes, but also in the vacuum. We explore a straight road to quantum gravity here--the one mandated by Clifford-algebra covariance. This bridges the gap from microscales--where the massive Dirac propagator is a sum over null zig-zags--to macroscales--where we see the energy-momentum current, *T and the resulting Einstein curvature, *G. For massive particles, *T flows in the "cosmic time" direction, y^0--centrifugally in an expanding universe. Neighboring centrifugal currents of *T present opposite spacetime vorticities *G to the boundaries of each others' worldtubes, so they advect--i.e. attract, as we show here by integrating a Spin^c-4 Lagrangian by parts in the spinfluid regime. This boundary integral not only explains why stress-energy *T is the source for gravitational curvature *G, but also gives a value for the gravitational constant, kappa(x^0) that depends on the current scale factor of our expanding Friedmann 3-brane. On the microscopic scale, quantum gravity appears naturally as the statistical mechanics of null zig-zags of massive particles in "imaginary time," y^0.
Jefferson Laboratory E93-038 Collaboration; :; B. Plaster; A. Yu. Semenov
2005-11-13
We report values for the neutron electric to magnetic form factor ratio, GEn/GMn, deduced from measurements of the neutron's recoil polarization in the quasielastic 2H(\\vec{e},e'\\vec{n})1H reaction, at three Q^2 values of 0.45, 1.13, and 1.45 (GeV/c)^2. The data at Q^2 = 1.13 and 1.45 (GeV/c)^2 are the first direct experimental measurements of GEn employing polarization degrees of freedom in the Q^2 > 1 (GeV/c)^2 region and stand as the most precise determinations of GEn for all values of Q^2.
Geometric scalar theory of gravity
Novello, M.; Bittencourt, E.; Goulart, E.; Salim, J.M.; Toniato, J.D.; Moschella, U. E-mail: eduhsb@cbpf.br E-mail: egoulart@cbpf.br E-mail: toniato@cbpf.br
2013-06-01
We present a geometric scalar theory of gravity. Our proposal will be described using the ''background field method'' introduced by Gupta, Feynman, Deser and others as a field theory formulation of general relativity. We analyze previous criticisms against scalar gravity and show how the present proposal avoids these difficulties. This concerns not only the theoretical complaints but also those related to observations. In particular, we show that the widespread belief of the conjecture that the source of scalar gravity must be the trace of the energy-momentum tensor — which is one of the main difficulties to couple gravity with electromagnetic phenomenon in previous models — does not apply to our geometric scalar theory. From the very beginning this is not a special relativistic scalar gravity. The adjective ''geometric'' pinpoints its similarity with general relativity: this is a metric theory of gravity. Some consequences of this new scalar theory are explored.
Abdelsamie, Maher A A; Mustafa, Shuhaimi; Hashim, Dzulkifly
2014-01-01
In this study, two software packages using different numerical techniques FEKO 6.3 with Finite-Element Method (FEM) and XFDTD 7 with Finite Difference Time Domain Method (FDTD) were used to assess exposure of 3D models of square, rectangular, and pyramidal shaped water containers to electromagnetic waves at 300, 900, and 2400 MHz frequencies. Using the FEM simulation technique, the peak electric field of 25, 4.5, and 2 V/m at 300 MHz and 15.75, 1.5, and 1.75 V/m at 900 MHz were observed in pyramidal, rectangular, and square shaped 3D container models, respectively. The FDTD simulation method confirmed a peak electric field of 12.782, 10.907, and 10.625 V/m at 2400 MHz in the pyramidal, square, and rectangular shaped 3D models, respectively. The study demonstrated an exceptionally high level of electric field in the water in the two identical pyramid shaped 3D models analyzed using the two different simulation techniques. Both FEM and FDTD simulation techniques indicated variations in the distribution of elect...
Entropic Gravity in Rindler Space
Edi Halyo
2011-04-13
We show that Rindler horizons are entropic screens and gravity is an entropic force in Rindler space by deriving the Verlinde entropy formula from the focusing of light due to a mass close to the horizon. Consequently, gravity is also entropic in the near horizon regions of Schwarzschild and de Sitter space-times. In different limits, the entropic nature of gravity in Rindler space leads to the Bekenstein entropy bound and the uncertainty principle.
Dynamic control of spin states in interacting magnetic elements
Jain, Shikha; Novosad, Valentyn
2014-10-07
A method for the control of the magnetic states of interacting magnetic elements comprising providing a magnetic structure with a plurality of interacting magnetic elements. The magnetic structure comprises a plurality of magnetic states based on the state of each interacting magnetic element. The desired magnetic state of the magnetic structure is determined. The active resonance frequency and amplitude curve of the desired magnetic state is determined. Each magnetic element of the magnetic structure is then subjected to an alternating magnetic field or electrical current having a frequency and amplitude below the active resonance frequency and amplitude curve of said desired magnetic state and above the active resonance frequency and amplitude curve of the current state of the magnetic structure until the magnetic state of the magnetic structure is at the desired magnetic state.
Shan Gao
2011-07-16
The remarkable connections between gravity and thermodynamics seem to imply that gravity is not fundamental but emergent, and in particular, as Verlinde suggested, gravity is probably an entropic force. In this paper, we will argue that the idea of gravity as an entropic force is debatable. It is shown that there is no convincing analogy between gravity and entropic force in Verlinde's example. Neither holographic screen nor test particle satisfies all requirements for the existence of entropic force in a thermodynamics system. Furthermore, we show that the entropy increase of the screen is not caused by its statistical tendency to increase entropy as required by the existence of entropic force, but in fact caused by gravity. Therefore, Verlinde's argument for the entropic origin of gravity is problematic. In addition, we argue that the existence of a minimum size of spacetime, together with the Heisenberg uncertainty principle in quantum theory, may imply the fundamental existence of gravity as a geometric property of spacetime. This may provide a further support for the conclusion that gravity is not an entropic force.
Peter West
2014-11-04
We consider the equation of motion in the gravity sector that arises from the non-linear realisation of the semi-direct product of E11 and its first fundamental representation, denoted by l1, in four dimensions. This equation is first order in derivatives and at low levels relates the usual field of gravity to a dual gravity field. When the generalised space-time is restricted to be the usual four dimensional space-time we show that this equation does correctly describe Einstein's theory at the linearised level. We also comment on previous discussions of dual gravity.
An Underlying Theory for Gravity
Yuan K. Ha
2012-08-14
A new direction to understand gravity has recently been explored by considering classical gravity to be a derived interaction from an underlying theory. This underlying theory would involve new degrees of freedom at a deeper level and it would be structurally different from classical gravitation. It may conceivably be a quantum theory or a non-quantum theory. The relation between this underlying theory and Einstein's gravity is similar to the connection between statistical mechanics and thermodynamics. We discuss the apparent lack of evidence of any quantum nature of gravity in this context.
Lifshitz Gravity for Lifshitz Holography
Tom Griffin; Petr Horava; Charles M. Melby-Thompson
2012-11-20
We argue that Horava-Lifshitz (HL) gravity provides the minimal holographic dual for Lifshitz-type field theories with anisotropic scaling and dynamical exponent z. First we show that Lifshitz spacetimes are vacuum solutions of HL gravity, without need for additional matter. Then we perform holographic renormalization of HL gravity, and show how it reproduces the full structure of the z=2 anisotropic Weyl anomaly in dual field theories in 2+1 dimensions, while its minimal relativistic gravity counterpart yields only one of two independent central charges in the anomaly.
Post, Wilfred M.
Electricity Delivery and Energy Reliability High Temperature Superconductivity (HTS) Visualization in the future because they have virtually no resistance to electric current, offering the possibility of new electric power equipment with more energy efficiency and higher capacity than today's systems
The role of information in gravity
M. Spaans
2009-07-24
It is argued that particle-specific information on energy-momentum adjusts the strength of gravity. This form of gravity has no free parameters, preserves Einstein gravity locally and predicts 6 times stronger accelerations on galaxy scales.
Gravity-Driven Intrusions in Stratified Fluids
Maurer, Benjamin D.
2011-01-01
5.5.1 Five interleaving interfacial gravity currents 5.5.2Ten interleaving interfacial gravity currents . 5.6in Iceland showing multiple gravity-driven intrusions c ´
Angular momentum transport via internal gravity waves in evolving stars
Fuller, Jim; Lecoanet, Daniel; Cantiello, Matteo; Brown, Ben
2014-11-20
Recent asteroseismic advances have allowed for direct measurements of the internal rotation rates of many subgiant and red giant stars. Unlike the nearly rigidly rotating Sun, these evolved stars contain radiative cores that spin faster than their overlying convective envelopes, but slower than they would in the absence of internal angular momentum transport. We investigate the role of internal gravity waves in angular momentum transport in evolving low-mass stars. In agreement with previous results, we find that convectively excited gravity waves can prevent the development of strong differential rotation in the radiative cores of Sun-like stars. As stars evolve into subgiants, however, low-frequency gravity waves become strongly attenuated and cannot propagate below the hydrogen-burning shell, allowing the spin of the core to decouple from the convective envelope. This decoupling occurs at the base of the subgiant branch when stars have surface temperatures of T ? 5500 K. However, gravity waves can still spin down the upper radiative region, implying that the observed differential rotation is likely confined to the deep core near the hydrogen-burning shell. The torque on the upper radiative region may also prevent the core from accreting high angular momentum material and slow the rate of core spin-up. The observed spin-down of cores on the red giant branch cannot be totally attributed to gravity waves, but the waves may enhance shear within the radiative region and thus increase the efficacy of viscous/magnetic torques.
K. H. Mariwalla
2002-05-28
Basis and limitations of singularity theorems for Gravity are examined. As singularity is a critical situation in course of time, study of time paths, in full generality of Equivalence principle, provides two mechanisms to prevent singularity. Resolution of singular Time translation generators into space of its orbits, and essential higher dimensions for Relativistic particle interactions has facets to resolve any real singularity problem. Conceptually, these varied viewpoints have a common denominator: arbitrariness in the definition of `energy' intrinsic to the space of operation in each case, so as to render absence of singularity a tautology for self-consistency of the systems.
Durmus A. Demir
2011-12-11
It is shown that, under a conformal transformation with reference to the Higgs field, the Higgs boson can be completely decoupled from electroweak interactions with no apparent change in known properties of leptons, quarks and vector bosons. Higgs boson becomes part of a scalar-tensor gravity which can be relevant for Dark Energy. It interacts with matter sector via higher-dimensional terms (e.g. neutrino Majorana mass), and via the fields (of new physics) whose masses are not generated by the Higgs mechanism. Dark Matter and two-Higgs-doublet model are the simplest examples.
Lubricated viscous gravity currents
Kowal, Katarzyna N.; Worster, M. Grae
2015-02-10
) at their base. The presence of subglacial meltwater can be attributed to geothermal heating, frictional heating from glacier sliding, and ice melting under pressure from the weight of the ice † Email address for correspondence: K.Kowal@damtp.cam.ac.uk 2 K. N... -fed and a constant head was maintained in the reservoir. To minimize the amount Lubricated viscous gravity currents 15 mirror syringe pump reservoir glass sheet perspex sheet screen Golden Syrup Salt Solution 1 m Figure 6: Schematic of our experimental...
King, Paul E. (Corvallis, OR); Woodside, Charles Rigel (Corvallis, OR)
2012-02-07
The disclosure herein provides an apparatus for location of a quantity of current vectors in an electrical device, where the current vector has a known direction and a known relative magnitude to an input current supplied to the electrical device. Mathematical constants used in Biot-Savart superposition equations are determined for the electrical device, the orientation of the apparatus, and relative magnitude of the current vector and the input current, and the apparatus utilizes magnetic field sensors oriented to a sensing plane to provide current vector location based on the solution of the Biot-Savart superposition equations. Description of required orientations between the apparatus and the electrical device are disclosed and various methods of determining the mathematical constants are presented.
Richmond Electric Vehicle Initiative Electric Vehicle Readiness...
Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site
Richmond Electric Vehicle Initiative Electric Vehicle Readiness Plan Richmond Electric Vehicle Initiative Electric Vehicle Readiness Plan The REVi plan addresses the electric...
Compact magnetic energy storage module
Prueitt, M.L.
1994-12-20
A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module. 4 figures.
Compact magnetic energy storage module
Prueitt, Melvin L. (Los Alamos, NM)
1994-01-01
A superconducting compact magnetic energy storage module in which a plurality of superconducting toroids, each having a toroidally wound superconducting winding inside a poloidally wound superconducting winding, are stacked so that the flow of electricity in each toroidally wound superconducting winding is in a direction opposite from the direction of electrical flow in other contiguous superconducting toroids. This allows for minimal magnetic pollution outside of the module.
Reduced models for quantum gravity
T. Thiemann
1999-10-04
The preceding talks given at this conference have dealt mainly with general ideas for, main problems of and techniques for the task of quantizing gravity canonically. Since one of the major motivations to arrange for this meeting was that it should serve as a beginner's introduction to canonical quantum gravity, we regard it as important to demonstrate the usefulness of the formalism by means of applying it to simplified models of quantum gravity, here formulated in terms of Ashtekar's new variables. From the various, completely solvable, models that have been discussed in the literature we choose those that we consider as most suitable for our pedagogical reasons, namely 2+1 gravity and the spherically symmetric model. The former model arises from a dimensional, the latter from a Killing reduction of full 3+1 gravity. While 2+1 gravity is usually treated in terms of closed topologies without boundary of the initial data hypersurface, the toplogy for the spherically symmetric system is chosen to be asymptotically flat. Finally, 2+1 gravity is more suitably quantized using the loop representation while spherically symmetric gravity is easier to quantize via the self-dual representation. Accordingly, both types of reductions, both types of topologies and both types of representations that are mainly employed in the literature in the context of the new variables come into practice. What makes the discussion especially clear is the fact that for both models the reduced phase space turns out to be finitely dimensional.
to directly detect hydrogen in liquids. In near surface applications wire loops may be deployed on the surface be monitored inductively on the earth's surface using wire loops that measure the changing emf due
A SUPERCONDUCTING MAGNET SYSTEM FOR THE SPIRIT COSMIC RAY SPACE TELESCOPE
Green, M.A.
2010-01-01
secondary circuit*® NbVSh superconducting coils ElectricalAugust 21-24, 1979 A SUPERCONDUCTING MAGNET SYSTEM FOR THETELESCOPE MASTER A SUPERCONDUCTING MAGNET SYSTEM FOR THE
Cafarella, Michael J.
Electrical + Computer Engineering Electrical + Computer Engineering 2013 PROFILE PEOPLE Faculty Students Electrical Engineering - 330 Computer Engineering - 224 Graduate Students EE and EE:Systems MSE - 301 EE and EE:Systems PhD - 296 Degrees Awarded Electrical Engineering BSE - 123 Computer Engineering
Nanolithographically defined magnetic structures and quantum magnetic disk (invited)
- creasing demands for magnetic storage devices with higher density, faster speed, lower power consumption, smaller size, and lower weight than the current state-of-the-art devices. Presently, most magnetic storage. Chou, Peter R. Krauss, and Linshu Kong NanoStructure Laboratory, Department of Electrical Engineering
Multi-winding homopolar electric machine
Van Neste, Charles W
2012-10-16
A multi-winding homopolar electric machine and method for converting between mechanical energy and electrical energy. The electric machine includes a shaft defining an axis of rotation, first and second magnets, a shielding portion, and a conductor. First and second magnets are coaxial with the shaft and include a charged pole surface and an oppositely charged pole surface, the charged pole surfaces facing one another to form a repulsive field therebetween. The shield portion extends between the magnets to confine at least a portion of the repulsive field to between the first and second magnets. The conductor extends between first and second end contacts and is toroidally coiled about the first and second magnets and the shield portion to develop a voltage across the first and second end contacts in response to rotation of the electric machine about the axis of rotation.
Abbin, J.P.; Andraka, C.E.; Lukens, L.L.; Moreno, J.B.
1992-01-14
An electrical pump for pumping liquid metals to high pressures in high temperature environments without the use of magnets or moving mechanical parts. The pump employs a non-porous solid electrolyte membrane, typically ceramic, specific to the liquid metal to be pumped. A DC voltage is applied across the thickness of the membrane causing ions to form and enter the membrane on the electrically positive surface, with the ions being neutralized on the opposite surface. This action provides pumping of the liquid metal from one side of the non-porous solid electrolyte membrane to the other. 3 figs.
Magnetic hydrogel with high coercivity
Sözeri, H.; Alvero?lu, E.; Kurtan, U.; ?enel, M.; Baykal, A.
2013-08-01
Highlights: • Polyacrylamide (PAAm) hydrogels containing magnetic BaFe{sub 12}O{sub 19} nanoparticles have been prepared. • Magnetization measurements reveal that hydrogels have hard magnetic properties with high coercivity. • Magnetic nanoparticles makes the gel more homogeneous and do not diffuse out of the gel during water intake. • These gels are useful in applications as wastewater treatment once gels are magnetized before its usage. - Abstract: This study investigates the synthesis and characterization of polyacrylamide (PAAm) hydrogels containing magnetic BaFe{sub 12}O{sub 19} nanoparticles. Structural, electrical, and magnetic characterization of the gels have been performed with X-ray powder diffractometry, scanning electron microscopy, DC conductivity, magnetization and fluorescence spectroscopy techniques. The preparation and characterization of polyacrylamide (PAAm) hydrogels that contain 5 and 10 mg BaFe{sub 12}O{sub 19} (16 and 21 nm diameter) nanoparticles are described herein. It is seen from the fluorescence spectra that, nanoparticles surrounded to pyranine molecules so that some of pyranine molecules could not bound to the polymer strands. Electrical measurements show that presence of nanoparticles make the gel more homogeneous. Magnetization measurements reveal that hydrogels have hard magnetic properties with quite high coercivity of 4.2 kOe, which does not change with swelling. This feature makes these gels useful in applications as wastewater treatment if they are magnetized before use.
Revealing Cosmic Magnetism with Radio Polarimetry
Bryan M. Gaensler
2007-12-18
While gravitation sustains the on-going evolution of the cosmos, it is magnetism that breaks gravity's symmetry and that provides the pathway to the non-thermal Universe. By enabling processes such as anisotropic pressure support, particle acceleration, and jet collimation, magnetism has for billions of years regulated the feedback vital for returning matter to the interstellar and intergalactic medium. After reviewing recent results that demonstrate the unique view of magnetic fields provided by radio astronomy, I explain how the Square Kilometre Array will provide data that will reveal what cosmic magnets look like, how they formed, and what role they have played in the evolving Universe.
Spin-gravity coupling and gravity-induced quantum phases
Giorgio Papini
2007-09-06
External gravitational fields induce phase factors in the wave functions of particles. The phases are exact to first order in the background gravitational field, are manifestly covariant and gauge invariant and provide a useful tool for the study of spin-gravity coupling and of the optics of particles in gravitational or inertial fields. We discuss the role that spin-gravity coupling plays in particular problems.
Gravity's Rainbow: a bridge towards Horava-Lifshitz gravity
Remo Garattini; Emmanuel N. Saridakis
2014-11-25
We investigate the connection between Gravity's Rainbow and Horava-Lifshitz gravity, since both theories incorporate a modification in the UltraViolet regime which improves their quantum behavior at the cost of the Lorentz invariance loss. In particular, extracting the Wheeler-De Witt equations of the two theories in the case of Friedmann-Lemaitre-Robertson-Walker and spherically symmetric geometries, we establish a correspondence that bridges them.
Seymour, P.
1986-01-01
This book deals with the cosmic magnetism in a non-mathematical way. It uses Faraday's very powerful and highly pictorial concept of lines of magnetic force and their associated physical properties to explain the structure and behavior of magnetic fields in extraterrestrial objects. Contents include: forces of nature; magnetic field of earth; solar and interplanetary magnetic fields; magnetic fields in the solar system; stars and pulsars; and magnetic fields of the milky way and other galaxies.
Electrical Spin Injection and Detection in Ge Nanowires and Topological Insulators
Tang, Jianshi
2014-01-01
L. -J. Chen, K. L. Wang, “Electrical Spin Injection andJ. Chen, K. L. Wang, “Electrical Probing of Magnetic PhaseM.P. & Jansen, R. Electrical Creation of Spin Polarization
Magnetic reconnection launcher
Cowan, M.
1987-04-06
An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in the launcher with the passage of a projectiles. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S. A gap portion of the projectile may be made from aluminum and is propelled by the reconnection of magnetic flux stored in the coils which causes accelerating forces to act upon the projectile and at the horizontal surfaces of the projectile near its rear. The gap portion of the projectile may be flat, rectangular and longer than the length of the opposing coils. The gap portion of the projectile permits substantially unrestricted distribution of the induced currents so that current densities are only high where the useful magnetic force is high. This allows designs which permit ohmic oblation from the rear surfaces of the gap portion of the projectile allowing much high velocities to be achieved. An electric power apparatus controls the electric power supplied to the opposing coils until the gap portion of the projectile substantially occupies the gap between the coils, at which time the coils are supplied with peak current quickly. 8 figs.
Deligöz, H.; Baykal, A.; Toprak, M.S.; Yildirim Beyazit University, Dept of Materials Science and Engineering, Ulus, Ankara ; Tanr?verdi, E.E.; Durmus, Z.; Sözeri, H.
2013-02-15
Graphical abstract: The variations of imaginary part of dielectric permittivity (??) of TEG@Co{sub 1?x}Zn{sub x}Fe{sub 2}O{sub 4} nanocomposite as a function of temperature and frequency for (A) x = 0.0 and (B) x = 0.2. Display Omitted Highlights: ? Nearly monodisperse Zn{sub x}Co{sub 1?x}Fe{sub 2}O{sub 4} nanocomposite were prepared via hydrothermal method. ? The ac conductivity showed a temperature dependent behavior at low frequencies. ? dc conductivity of Co{sub 0.8}Zn{sub 0.2}Fe{sub 2}O{sub 4} nanoparticle are found to obey the Arrhenius plot. ? Also these materials may be used in electronic devices and microwave devices. -- Abstract: Co{sub 1?x}Zn{sub x}Fe{sub 2}O{sub 4} spinel nanoparticles with Zn concentrations of x = 0.0, 0.2 were prepared by a hydrothermal route in the presence of triethylene glycol (TEG). The structural, magnetic, electrical and dielectric properties of the prepared nanoparticles were studied. The XRD results confirmed the formation of single spinel ferrite structure with crystallite size 9 and 10 nm for x = 0.0 and 0.2 compositions respectively. The lattice parameter (a) increased with increasing Zn concentration. Temperature and frequency dependent electrical and dielectric properties of the prepared ferrites have also been investigated. Our findings show that overall conductivity of Co{sub 0.8}Zn{sub 0.2}Fe{sub 2}O{sub 4} nanoparticle is lower than that of CoFe{sub 2}O{sub 4} and roughly in the range of 10{sup ?11}–10{sup ?7} S cm{sup ?1} depending strongly temperature and frequency owing to the formation of stable electric bonds between the Zn{sup 2+} and Fe{sup 2+} ions, which localizes Fe{sup 2+} charge carriers. The ac conductivity showed a temperature dependent behavior at low frequencies and temperature independent behavior at high frequencies, which is an indication of ionic conductivity. dc conductivity of Co{sub 0.8}Zn{sub 0.2}Fe{sub 2}O{sub 4} nanoparticle are found to obey the Arrhenius plot and can be classified into two regions over with activation energy of 0.113 and 0.163 eV in the ranges of 20–40 °C and 70–120 °C, respectively when CoFe{sub 2}O{sub 4} has an activation energy of 0.245 eV.
Cosmological perturbations in unimodular gravity
Gao, Caixia; Brandenberger, Robert H.; Cai, Yifu; Chen, Pisin E-mail: rhb@hep.physics.mcgill.ca E-mail: chen@slac.stanford.edu
2014-09-01
We study cosmological perturbation theory within the framework of unimodular gravity. We show that the Lagrangian constraint on the determinant of the metric required by unimodular gravity leads to an extra constraint on the gauge freedom of the metric perturbations. Although the main equation of motion for the gravitational potential remains the same, the shift variable, which is gauge artifact in General Relativity, cannot be set to zero in unimodular gravity. This non-vanishing shift variable affects the propagation of photons throughout the cosmological evolution and therefore modifies the Sachs-Wolfe relation between the relativistic gravitational potential and the microwave temperature anisotropies. However, for adiabatic fluctuations the difference between the result in General Relativity and unimodular gravity is suppressed on large angular scales. Thus, no strong constraints on the theory can be derived.
Gravity Currents in Aquatic Canopies
Tanino, Yukie
A lock exchange experiment is used to investigate the propagation of gravity currents through a random array of rigid, emergent cylinders which represents a canopy of aquatic plants. As canopy drag increases, the propagating ...
Gravity as an Entropic Phenomenon
Abhiram Chivukula
2010-11-19
The unification of gravity with the three other forces has been an important goal of physics for some time now, because a quantum theory of gravity is necessary to explain the universe at its earliest moments. Its pursuit has largely assumed gravity's independent existence, but E. Verlinde proposed that gravity is not a fundamental force but a macroscopic phenomenon that emerges as a result of thermodynamic principles applied to the information of mass distributions. Under this framework we consider the roles played by quantum microstates, entanglement, information theory, the AdS/CFT Correspondence, and String Theory in general. We also ask whether Verlinde's proposal suggests that action principles should be thermodynamic in nature.
Gravity as an Entropic Phenomenon
Chivukula, Abhiram
2010-01-01
The unification of gravity with the three other forces has been an important goal of physics for some time now, because a quantum theory of gravity is necessary to explain the universe at its earliest moments. Its pursuit has largely assumed gravity's independent existence, but E. Verlinde proposed that gravity is not a fundamental force but a macroscopic phenomenon that emerges as a result of thermodynamic principles applied to the information of mass distributions. Under this framework we consider the roles played by quantum microstates, entanglement, information theory, the AdS/CFT Correspondence, and String Theory in general. We also ask whether Verlinde's proposal suggests that action principles should be thermodynamic in nature.
Testing Gravity Theories Using Stars
Jeremy Sakstein; Bhuvnesh Jain; Vinu Vikram
2014-09-12
Modified theories of gravity have received a renewed interest due to their ability to account for the cosmic acceleration. In order to satisfy the solar system tests of gravity, these theories need to include a screening mechanism that hides the modifications on small scales. One popular and well-studied theory is chameleon gravity. Our own galaxy is necessarily screened, but less dense dwarf galaxies may be unscreened and their constituent stars can exhibit novel features. In particular, unscreened stars are brighter, hotter and more ephemeral than screened stars in our own galaxy. They also pulsate with a shorter period. In this essay, we exploit these new features to constrain chameleon gravity to levels three orders of magnitude lower the previous measurements. These constraints are currently the strongest in the literature.
Spin-stabilized magnetic levitation without vertical axis of rotation
Romero, Louis (Albuquerque, NM); Christenson, Todd (Albuquerque, NM); Aaronson, Gene (Albuquerque, NM)
2009-06-09
The symmetry properties of a magnetic levitation arrangement are exploited to produce spin-stabilized magnetic levitation without aligning the rotational axis of the rotor with the direction of the force of gravity. The rotation of the rotor stabilizes perturbations directed parallel to the rotational axis.
Electric fields and quantum wormholes
Dalit Engelhardt; Ben Freivogel; Nabil Iqbal
2015-05-24
Electric fields can thread a classical Einstein-Rosen bridge. Maldacena and Susskind have recently suggested that in a theory of dynamical gravity the entanglement of ordinary perturbative quanta should be viewed as creating a quantum version of an Einstein-Rosen bridge between the particles, or a "quantum wormhole". We demonstrate within low-energy effective field theory that there is a precise sense in which electric fields can also thread such quantum wormholes. We define a non-perturbative "wormhole susceptibility" that measures the ease of passing an electric field through any sort of wormhole. The susceptibility of a quantum wormhole is suppressed by powers of the U(1) gauge coupling relative to that for a classical wormhole but can be made numerically equal with a sufficiently large amount of entangled matter.
Dualities and Emergent Gravity: Gauge/Gravity Duality
Sebastian de Haro
2015-09-09
In this paper I develop a framework for relating dualities and emergence: two notions that are close to each other but also exclude one another. I adopt the conception of duality as 'isomorphism', cashing it out in terms of three conditions. These three conditions prompt two conceptually different ways in which a duality can be modified to make room for emergence; and I argue that this exhausts the possibilities for combining dualities and emergence (via coarse-graining). I apply this framework to gauge/gravity dualities, considering in detail three examples: AdS/CFT, Verlinde's scheme, and black holes. My main point about gauge/gravity dualities is that the theories involved, qua theories of gravity, must be background-independent. I distinguish two senses of background-independence: (i) minimalistic and (ii) extended. The former is sufficiently strong to allow for a consistent theory of quantum gravity; and AdS/CFT is background-independent on this account; while Verlinde's scheme best fits the extended sense. I argue that this extended sense should be applied with some caution: on pain of throwing the baby (general relativity) out with the bath-water (extended background-independence). Nevertheless, it is an interesting and potentially fruitful heuristic principle for quantum gravity theory construction. The interpretation of dualities is articulated in terms of: (i) epistemic and metaphysical commitments; (ii) parts vs. wholes. I then analyse the emergence of gravity in gauge/gravity dualities in terms of the two available conceptualisations of emergence; and I show how emergence in AdS/CFT and in Verlinde's scenario differ from each other. Finally, I give a novel derivation of the Bekenstein-Hawking black hole entropy formula based on Verlinde's scheme; the derivation sheds light on several aspects of Verlinde's scheme and how it compares to Bekenstein's original calculation.
E. Gaztanaga; R. Juszkiewicz
2001-08-21
We present a new constraint on the biased galaxy formation picture. Gravitational instability theory predicts that the two-point mass density correlation function, \\xi(r), has an inflection point at the separation r=r_0, corresponding to the boundary between the linear and nonlinear regime of clustering, \\xi = 1. We show how this feature can be used to constrain the square of the biasing parameter, b^2 = \\xi_g / \\xi on scales r = r_0, where \\xi_g is the galaxy-galaxy correlation function, allowed to differ from \\xi. We apply our method to real data: the \\xi_g(r), estimated from the APM galaxy survey. Our results suggest that the APM galaxies trace the mass at separations r > 5 Mpc/h, where h is the Hubble constant in units of 100 km/s Mpc. The present results agree with earlier studies, based on comparing higher order correlations in the APM with weakly non-linear perturbation theory. Both approaches constrain the "b" factor to be within 20% of unity. If the existence of the feature we identified in the APM \\xi_g(r) -- the inflection point near \\xi_g = 1 -- is confirmed by more accurate surveys, we may have discovered gravity's smoking gun: the long awaited ``shoulder'' in \\xi, predicted by Gott and Rees 25 years ago.
D. Fargion
2005-11-23
The present gravitational wave detectors are reaching lowest metric deviation fields able to detect galactic and extra-galactic gravitational waves, related to Supernova explosions up to Virgo cluster. The same gravitational wave detector are nevertheless almost able to reveal, in principle, near field Newtonian gravitational perturbations due to fast huge mass displacements as the ones occurring during largest Earth-Quake or Tsunami as the last on 26nd December 2004 in Asiatic area. Virgo and Ligo detector are unfortunately recording on high frequencies (above tens Hz) while the signal of the Tsunami lay at much lower range (below 0.1 Hz). Nevertheless prompt gravitational near field deformation by the Tsunami might reach the future LISA threshold sensitivity and frequency windows if such an array is located nearby (3000-10000) km distances. Unfortunately the present LISA system should be located at Lagrange point too far (1.5 million km. far away). We note however that the later continental mass rearrangement and their gravitational field assessment on Earth must induce, for Richter Magnitude 9-like Tsunami, a different terrestrial inertia momentum and a different principal rotation axis. In conclusion we remind that gravitational geodetic deviation on new precise satellites (GOCE 2006), assisted by GPS network, might nevertheless reach in the near future the needed threshold and accuracy to reveal Tsunami by their prompt tidal gravity field deviations . An array of such geoid detector maybe correlated with LISA-like satellite on Earth orbits may offer the fastest alarm system.
Dust gravitational drift wave in complex plasma under gravity
Salahshoor, M. Niknam, A. R.
2014-12-15
The dispersion relation of electrostatic waves in a complex plasma under gravity is presented. It is assumed that the waves propagate parallel to the external fields. The effects of weak electric field, neutral drag force, and ion drag force are also taken into account. The dispersion relation is numerically examined in an appropriate parameter space in which the gravity plays the dominant role in the dynamics of microparticles. The numerical results show that, in the low pressure complex plasma under gravity, a low frequency drift wave can be developed in the long wavelength limit. The stability state of this wave is switched at a certain critical wavenumber in such a way that the damped mode is transformed into a growing one. Furthermore, the influence of the external fields on the dispersion properties is analyzed. It is shown that the wave instability is essentially due to the electrostatic streaming of plasma particles. It is also found that by increasing the electric field strength, the stability switching occurs at smaller wavenumbers.
Magnetic-cusp, cathodic-arc source
Falabella, Steven (Livermore, CA)
1995-01-01
A magnetic-cusp for a cathodic-arc source wherein the arc is confined to the desired cathode surface, provides a current path for electrons from the cathode to the anode, and utilizes electric and magnetic fields to guide ions from the cathode to a point of use, such as substrates to be coated. The magnetic-cusp insures arc stability by an easy magnetic path from anode to cathode, while the straight-through arrangement leads to high ion transmission.
Liu, Jia; Bai, Wei E-mail: xdtang@sist.ecnu.edu.cn; Yang, Jing; Xu, Wenfei; Zhang, Yuanyuan; Tang, Xiaodong E-mail: xdtang@sist.ecnu.edu.cn; Lin, Tie; Meng, Xiangjian; Duan, Chun-Gang; Chu, Junhao
2013-12-21
Aurivillius Bi{sub 5}Ti{sub 3}FeO{sub 15} (BTFO) multiferroic ceramics with different Cr-doped concentrations have been synthesized by the conventional solid state reaction method. The influences of Cr-doping concentrations on the structural, magnetic, dielectric, and ferroelectric properties of BTFO ceramics are investigated in detail. All these sintered Cr-substituted BTFO ceramics are determined to be layered perovskite Aurivillius structure by X-ray diffraction, as well as the lattice parameters a, b, and c are in good accordance with Vegard's law along with the Cr-doping concentration. The lattice distortion a/b for Aurivillius family decreases with increasing Cr-doping concentration. Moreover, Cr-doping can promote greatly the grain growth of BTFO samples confirmed from field emission scanning electron microscopy characterization. However, no obvious signs of the improvement in ferroelectric properties are found in Cr-doped BTFO ceramics, and abnormal ferroelectric polarization versus electric field (P-E) loops are observed as Cr-doping content is beyond 0.1. Similar ? (tan?) versus frequency plots to those of the BTFO sample are exhibited when Cr-doping concentration is less than 0.1. Nevertheless, obvious dielectric dispersion phenomena are shown as the Cr-doping concentration is beyond 0.1, and this dispersion behavior becomes strong with further increasing Cr-doping concentration, which are clearly indicated by the appearance of dielectric loss relaxation peaks in the measurement frequency from 10{sup 2} Hz to 10{sup 6} Hz. In addition, the corresponding frequency to relaxation peak shifts towards high frequencies with the Cr-doping concentration. Finally, the same magnetic orderings for all these Cr-doped BTFO ceramics as those of the BTFO one, i.e., superparamagnetic state dominated with antiferromagnetic interaction, are unambiguously found, signifying that the predicted Fe{sup 3+}-O-Cr{sup 3+} 180° ferromagnetic superexchange interaction based on the Goodenough-Kanamori (G-K) rule might not be achieved in BTFO ceramics through Cr substitution by the conventional solid state reaction.
Conformal Lifshitz Gravity from Holography
Tom Griffin; Petr Horava; Charles M. Melby-Thompson
2012-04-03
We show that holographic renormalization of relativistic gravity in asymptotically Lifshitz spacetimes naturally reproduces the structure of gravity with anisotropic scaling: The holographic counterterms induced near anisotropic infinity take the form of the action for gravity at a Lifshitz point, with the appropriate value of the dynamical critical exponent $z$. In the particular case of 3+1 bulk dimensions and $z=2$ asymptotic scaling near infinity, we find a logarithmic counterterm, related to anisotropic Weyl anomaly of the dual CFT, and show that this counterterm reproduces precisely the action of conformal gravity at a $z=2$ Lifshitz point in 2+1 dimensions, which enjoys anisotropic local Weyl invariance and satisfies the detailed balance condition. We explain how the detailed balance is a consequence of relations among holographic counterterms, and point out that a similar relation holds in the relativistic case of holography in $AdS_5$. Upon analytic continuation, analogous to the relativistic case studied recently by Maldacena, the action of conformal gravity at the $z=2$ Lifshitz point features in the ground-state wavefunction of a gravitational system with an interesting type of spatial anisotropy.
Mechanical vibration to electrical energy converter
Kellogg, Rick Allen (Tijeras, NM); Brotz, Jay Kristoffer (Albuquerque, NM)
2009-03-03
Electromechanical devices that generate an electrical signal in response to an external source of mechanical vibrations can operate as a sensor of vibrations and as an energy harvester for converting mechanical vibration to electrical energy. The devices incorporate a magnet that is movable through a gap in a ferromagnetic circuit, wherein a coil is wound around a portion of the ferromagnetic circuit. A flexible coupling is used to attach the magnet to a frame for providing alignment of the magnet as it moves or oscillates through the gap in the ferromagnetic circuit. The motion of the magnet can be constrained to occur within a substantially linear range of magnetostatic force that develops due to the motion of the magnet. The devices can have ferromagnetic circuits with multiple arms, an array of magnets having alternating polarity and, encompass micro-electromechanical (MEM) devices.
Argonne National Laboratory Partners with Advanced Magnet Lab...
Broader source: Energy.gov (indexed) [DOE]
next generation wind turbines and accelerate the deployment of advanced turbines for offshore wind energy in the United States. ANL will work with Magnet Lab, Emerson Electric...
Turbulence may be key to "fast magnetic reconnection" mystery
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
magnetic reconnection" mystery The new research could lead to better understanding of solar flares and ejections of material from the Sun's corona. July 11, 2013 Electric...
Pereira, Antonio Do Nascimento
2013-04-05
FAULT MAPPING USING THE MAGNETIC METHOD AT HICKORY SANDSTONE AQUIFER, LLANO UPLIFT, TEXAS A Thesis by ANT ONIO DO NASCIMENTO PEREIRA Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements... Magnetic eld or, Magnetic induction or, Magnetic eld density or, Magnetic ux density E Electric eld intensity H Magnetic eld intensity J Magnetizing eld, 0 Permeability of free space M Magnetic moment U Scalar potential v TABLE OF CONTENTS...
Cannan, Chad; Bartel, Lewis; Palisch, Terrence; Aldridge, David
2015-01-13
Electrically conductive proppants and methods for detecting, locating, and characterizing same are provided. The electrically conductive proppant can include a substantially uniform coating of an electrically conductive material having a thickness of at least 500 nm. The method can include injecting a hydraulic fluid into a wellbore extending into a subterranean formation at a rate and pressure sufficient to open a fracture therein, injecting into the fracture a fluid containing the electrically conductive proppant, electrically energizing the earth at or near the fracture, and measuring three dimensional (x, y, and z) components of electric and magnetic field responses at a surface of the earth or in an adjacent wellbore.
Ozpineci, Burak
2014-07-23
Burak Ozpineci sees a future where electric vehicles charge while we drive them down the road, thanks in part to research under way at ORNL.
Ozpineci, Burak
2014-05-02
Burak Ozpineci sees a future where electric vehicles charge while we drive them down the road, thanks in part to research under way at ORNL.
Thermodynamic properties of a magnetically modulated graphene
SK Firoz Islam; Naveen K. Singh; Tarun Kanti Ghosh
2011-09-12
The effect of magnetic modulation on thermodynamic properties of a graphene monolayer in presence of a constant perpendicular magnetic field is reported here. One-dimensional spatial electric or magnetic modulation lifts the degeneracy of the Landau levels and converts into bands and their band width oscillates with magnetic field leading to Weiss-type oscillation in the thermodynamic properties. The effect of magnetic modulation on thermodynamic properties of a graphene sheet is studied and then compared with electrically modulated graphene and magnetically modulated conventional two-dimensional electron gas (2DEG). We observe Weiss-type and de Haas-van Alphen (dHvA) oscillations at low and high magnetic field, respectively. There is a definite phase difference in Weiss-type oscillations in thermodynamic quantities of magnetically modulated graphene in compare to electrically modulated graphene. On the other hand, the phase remains same and amplitude of the oscillation is large when compared with the magnetically modulated 2DEG. Explicit asymptotic expressions of density of states and the Helmholtz free energy are provided to understand the phase and amplitude of the Weiss-type oscillations qualitatively. We also study thermodynamic properties when both electric and magnetic modulations are present. The Weiss-type oscillations still exist when the modulations are out-of-phase.
International Electric Propulsion Conference IEPC-2007-153
King, Lyon B.
30th International Electric Propulsion Conference IEPC-2007-153 1 Confinement time in an electron and magnetic fields of a Hall-effect thruster with the goal of understanding the mechanism(s) responsible for anomalous cross-field mobility. A low-density electron plasma is confined using vacuum electric and magnetic
Foundations of Electrical Engineering Civil & Environmental Engineers
Oughstun, Kurt
of Electricity & Magnetism (1/131/15) Gauss' laws Faraday's law: electric potential, Kirchhoff's voltage law (KVL) Amp`ere's law: conservation of charge, Kirchhoff's current law (KCL) Ohm's law: resistance for circuit elements impedance & admittance series & parallel combinations of circuit elements voltage
New Models of f(R) Theories of Gravity
J. Kluson
2009-11-04
We introduce new models of f(R) theories of gravity that are generalization of Horava-Lifshitz gravity.
The Gravity Field of the Earth and Coriolis Effects.... The gravity field
Riser, Stephen C.
The Gravity Field of the Earth and Coriolis Effects.... The gravity field Stationary particles #12;Gravity.... Newton's Universal Law of Gravitation: The force between any two particles having.673 ×10-11 newton-meter2/kilogram2) #12;Gravity.... In vector form, or, 21 è force on 2 due to 1 12 è
Modified Entropic Gravity and Cosmology
Miguel Zumalacarregui
2012-02-06
It has been recently proposed that gravity might be an entropic force. Although a well defined fundamental description for such a mechanism is still lacking, it is still possible to address the viability of phenomenological models of entropic-inspired modified gravities. I will summarize some recent work directed to using cosmology as a tool to constraint scenarios in which the modifications are aimed to explain the physics behind dark energy and inflation. A phenomenological modification is able to explain cosmic acceleration at the background level and fit observations, but simple inflation models with higher curvature corrections are in conflict with late time matter domination.
Starobinsky Model in Rainbow Gravity
Chatrabhuti, Auttakit; Channuie, Phongpichit
2015-01-01
In this work, we study Starobinsky model of inflation in the context of gravity's rainbow theory. We propose that gravity rainbow functions can be written in the power-law form of the Hubble parameter. We present a detailed derivation of the spectral index of curvature perturbation and the tensor-to-scalar ratio and compare the predictions of our models with Planck 2015 data. We discover, by taking $N_{k}=70$ e-folds and requiring our predictions to agree with the Planck data at the one sigma confidence level, the rainbow parameter would satisfy $\\lambda\\lesssim 1.0$.
de Sitter gravity/Euclidean conformal gravity correspondence
Chatterjee, Atreya
2015-01-01
The holographic dual of a gravitational theory around the de Sitter background is argued to be a Euclidean conformal gravity theory in one fewer dimensions. The measure for the holographic theory naturally includes a sum over topologies as well as conformal structures.
Enhancement of artificial magnetism via resonant bianisotropy
Markovich, Dmitry; Shalin, Alexander; Samusev, Anton; Krasnok, Alexander; Belov, Pavel; Ginzburg, Pavel
2015-01-01
All-dielectric "magnetic light" nanophotonics based on high refractive index nanoparticles allows controlling magnetic component of light at nanoscale without having high dissipative losses. The artificial magnetic optical response of such nanoparticles originates from circular displacement currents excited inside those structures and strongly depends on geometry and dispersion of optical materials. Here a new approach for increasing magnetic response via resonant bianisotropy effect is proposed and analyzed. The key mechanism of enhancement is based on electric-magnetic interaction between two electrically and magnetically resonant nanoparticles of all-dielectric dimer nanoantenna. It was shown that proper geometrical arrangement of the dimer in respect to the incident illumination direction allows flexible control over all vectorial components of magnetic polarizability, tailoring the later in the dynamical range of 100 % and enhancement up to 36 % relative to performances of standalone spherical particles....
ELECTRICAL ENGINEERING Page 1 of 7 Pre-and/or Co-Requisites
ELECTRICAL ENGINEERING Page 1 of 7 1st Year Pre- and/or Co-Requisites FALL 1 AMAT 217 Calculus 259 Electricity and Magnetism AMAT 217; MATH 211 2nd Year Electrical Engineering: Regular Program Pre #12;ELECTRICAL ENGINEERING Page 2 of 7 2nd Year (continued) Electrical Engineering: Energy
Gravity Transform for Input Conditioning in
Paiva, António R. C.
Gravity Transform for Input Conditioning in Brain Machine Interfaces António R. C. Paiva, José C. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data Analysis #12;3 Outline 1. Motivation 2. Methods i. Gravity Transform ii. Modeling and output sensitivity analysis 3. Data
Emergent 4D Gravity from Matrix Models
Harold Steinacker
2007-12-19
Recent progress in the understanding of gravity on noncommutative spaces is discussed. A gravity theory naturally emerges from matrix models of noncommutative gauge theory. The effective metric depends on the dynamical Poisson structure, absorbing the degrees of freedom of the would-be U(1) gauge field. The gravity action is induced upon quantization.
Magnets & Magnet Condensed Matter Science
McQuade, D. Tyler
Sights from around the Magnet Lab in 2010. On the cover MAGNETS & MAGNET MATERIALS Engineering materials in Mesoporous Silica SBA-15 31 YBCO Pancake Wound Test Coil for 32-T Magnet Development 32 Strong Vortex Pinning from Marine Cyanobacteria 37 Heavy Petroleum Composition 2. Progression of the Boduszynski Model
Electron electric dipole moment experiment using electric-field quantized slow cesium atoms
Amini, Jason M.; Munger Jr., Charles T.; Gould, Harvey
2007-01-01
electric-?eld quantized slow cesium atoms Jason M. Amini, ?e-EDM) experiment using slow cesium atoms, nulled magnetic ?enhancement factor R for the cesium ground state is 114 ±
Electric machine for hybrid motor vehicle
Hsu, John Sheungchun (Oak Ridge, TN)
2007-09-18
A power system for a motor vehicle having an internal combustion engine and an electric machine is disclosed. The electric machine has a stator, a permanent magnet rotor, an uncluttered rotor spaced from the permanent magnet rotor, and at least one secondary core assembly. The power system also has a gearing arrangement for coupling the internal combustion engine to wheels on the vehicle thereby providing a means for the electric machine to both power assist and brake in relation to the output of the internal combustion engine.
Exchange-Spring Magnets: Nanocomposite Exchange-Spring Magnets for Motor and Generator Applications
2012-01-01
REACT Project: ANL will develop a cost-effective exchange-spring magnet to use in the electric motors of wind generators and EVs that uses no rare earth materials. This ANL exchange-spring magnet combines a hard magnetic outer shell with a soft magnetic inner core—coupling these together increases the performance (energy density and operating temperature). The hard and soft magnet composite particles would be created at the molecular level, followed by consolidation in a magnetic field. This process allows the particles to be oriented to maximize the magnetic properties of low-cost and abundant metals, eliminating the need for expensive imported rare earths. The ultimate goal of this project is to demonstrate this new type of magnet in a prototype electric motor.
The electrically charged universe
Michael Düren
2012-01-31
The paper discusses the possibility of a universe that is not electrically neutral but has a net positive charge. It is claimed that such a universe contains a homogeneous distribution of protons that are not bound to galaxies and fill up the intergalactic space. This proton `gas' charges macroscopic objects like stars and planets, but it does not generate electrostatic or magnetic fields that affect the motion of these bodies significantly. However, the proton gas may contribute significantly to the total dark matter of the universe and its electrostatic potential may contribute to the dark energy and to the expansion of the universe.
Electrically tunable transverse magnetic focusing in graphene
Taychatanapat, Thiti
Electrons in a periodic lattice can propagate without scattering for macroscopic distances despite the presence of the non-uniform Coulomb potential due to the nuclei. Such ballistic motion of electrons allows the use of ...
Global Electrical Conductivity Magnetic Satellite Induction Studies
Constable, Steve
CHAMPMeeting, September2003 c S.Constable SCRIPPSINST ITUTION OF OCE ANOGRAPHY UCSD #12;Contents: · Background: Earth conductivity · Background: EM induction · Some satellite results 2ndCHAMPMeeting, September2003 c SCHAMPMeeting, September2003 c S.Constable SCRIPPSINST ITUTION OF OCE ANOGRAPHY UCSD #12;Conductivity of Earth materials
Advanced Electric Traction System Technology Development
Anderson, Iver
2011-01-14
As a subcontractor to General Motors (GM), Ames Laboratory provided the technical expertise and supplied experimental materials needed to assess the technology of high energy bonded permanent magnets that are injection or compression molded for use in the Advanced Electric Traction System motor. This support was a sustained (Phase 1: 6/07 to 3/08) engineering effort that builds on the research achievements of the primary FreedomCAR project at Ames Laboratory on development of high temperature magnet alloy particulate in both flake and spherical powder forms. Ames Lab also provide guidance and direction in selection of magnet materials and supported the fabrication of experimental magnet materials for development of injection molding and magnetization processes by Arnold Magnetics, another project partner. The work with Arnold Magnetics involved a close collaboration on particulate material design and processing to achieve enhanced particulate properties and magnetic performance in the resulting bonded magnets. The overall project direction was provided by GM Program Management and two design reviews were held at GM-ATC in Torrance, CA. Ames Lab utilized current expertise in magnet powder alloy design and processing, along with on-going research advances being achieved under the existing FreedomCAR Program project to help guide and direct work during Phase 1 for the Advanced Electric Traction System Technology Development Program. The technical tasks included review of previous GM and Arnold Magnets work and identification of improvements to the benchmark magnet material, Magnequench MQP-14-12. Other benchmark characteristics of the desired magnet material include 64% volumetric loading with PPS polymer and a recommended maximum use temperature of 200C. A collaborative relationship was maintained with Arnold Magnets on the specification and processing of the bonded magnet material required by GM-ATC.