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1

Electric Dipole Moment of Magnetic Monopole

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).

Makoto Kobayashi

2007-03-07

2

Table of nuclear magnetic dipole and electric quadrupole moments

The table is a compilation of experimental measurements of static magnetic dipole and electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin, and parity are given, along with a brief indication of the method and any reference standard used in the particular

N. J. Stone

2005-01-01

3

Table of Nuclear Magnetic Dipole and Electric Quadrupole Moments

of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energyTable of Nuclear Magnetic Dipole and Electric Quadrupole Moments N.J.Stone, Oxford Physics, Clarendon Laboratory Parks Road, OXFORD OX1 3PU U.K. This Table is a compilation of experimental

4

Dark-matter electric and magnetic dipole moments

We consider the consequences of a neutral dark-matter particle with a nonzero electric and/or magnetic dipole moment. Theoretical constraints, as well as constraints from direct searches, precision tests of the standard-model, the cosmic microwave background and matter power spectra, and cosmic gamma rays, are included. We find that a relatively light particle with mass between an MeV and a few GeV and an electric or magnetic dipole as large as {approx}3x10{sup -16}e cm (roughly 1.6x10{sup -5}{mu}{sub B}) satisfies all experimental and observational bounds. Some of the remaining parameter space may be probed with forthcoming more sensitive direct searches and with the Gamma-Ray Large Area Space Telescope.

Sigurdson, Kris; Kurylov, Andriy; Kamionkowski, Marc [California Institute of Technology, Mail Code 130-33, Pasadena, California 91125 (United States); Doran, Michael; Caldwell, Robert R. [Department of Physics and Astronomy, Dartmouth College, 6127 Wilder Laboratory, Hanover, New Hampshire 03755 (United States)

2004-10-15

5

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{sub 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 {sup 129}Xe, {sup 171}Yb, {sup 199}Hg, {sup 211}Rn, and {sup 225}Ra have been calculated numerically. From the experimental limits on the atomic EDMs of {sup 129}Xe and {sup 199}Hg we have placed the following constraints on the nuclear EDMs, |d{sub N}({sup 129}Xe)|<1.1x10{sup -21}|e|cm and |d{sub N}({sup 199}Hg)|<2.8x10{sup -24}|e|cm.

Porsev, S. G. [School of Physics, University of New South Wales, Sydney NSW 2052 (Australia); Petersburg Nuclear Physics Institute, Gatchina, Leningrad district 188300 (Russian Federation); Ginges, J. S. M.; Flambaum, V. V. [School of Physics, University of New South Wales, Sydney NSW 2052 (Australia)

2011-04-15

6

Magnetic and Electric Dipole Constraints on Extra Dimensions and Magnetic Fluxes

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.

Aaron J. Roy; Myron Bander

2008-05-10

7

Fluorescence lifetime of magnetic and electric dipoles near a dielectric interface

The fluorescence lifetime of an excited molecule described as a classical oscillating dipole in front of a partially reflecting plane interface is studied theoretically, the lifetime being inversely proportional to the radiated power. A new relation between the powers radiated by magnetic and electric dipoles is derived. For the powers radiated by magnetic and electric dipoles lying on or very

W. Lukosz; R. E. Kunz

1977-01-01

8

Dynamically fluctuating electric dipole moments in fullerene-based magnets.

We report here the direct evidence of the existence of a permanent electric dipole moment in both crystal phases of a fullerene-based magnet--the ferromagnetic ?-phase and the antiferromagnetic ?'-phase of tetra-kis-(dimethylamino)-ethylene-C60 (TDAE-C60)--as determined by dielectric measurements. We propose that the permanent electric dipole originates from the pairing of a TDAE molecule with surrounding C60 molecules. The two polymorphs exhibit clear differences in their dielectric responses at room temperature and during the freezing process with dynamically fluctuating electric dipole moments, although no difference in their room-temperature structures has been previously observed. This result implies that two polymorphs have different local environment around the molecules. In particular, the ferromagnetism of the ?-phase is founded on the homogeneous molecule displacement and orientational ordering. The formation of the different phases with respect to the different rotational states in the Jahn-Teller distorted C60s is also discussed. PMID:25236361

Kambe, Takashi; Oshima, Kokichi

2014-01-01

9

Dynamically fluctuating electric dipole moments in fullerene-based magnets

We report here the direct evidence of the existence of a permanent electric dipole moment in both crystal phases of a fullerene-based magnetthe ferromagnetic ?-phase and the antiferromagnetic ??-phase of tetra-kis-(dimethylamino)-ethylene-C60 (TDAE-C60)as determined by dielectric measurements. We propose that the permanent electric dipole originates from the pairing of a TDAE molecule with surrounding C60 molecules. The two polymorphs exhibit clear differences in their dielectric responses at room temperature and during the freezing process with dynamically fluctuating electric dipole moments, although no difference in their room-temperature structures has been previously observed. This result implies that two polymorphs have different local environment around the molecules. In particular, the ferromagnetism of the ?-phase is founded on the homogeneous molecule displacement and orientational ordering. The formation of the different phases with respect to the different rotational states in the JahnTeller distorted C60s is also discussed. PMID:25236361

Kambe, Takashi; Oshima, Kokichi

2014-01-01

10

Table of nuclear magnetic dipole and electric quadrupole moments

The table is a compilation of experimental measurements of static magnetic dipole and electric quadrupole moments of ground states and excited states of atomic nuclei throughout the periodic table. To aid identification of the states, their excitation energy, half-life, spin, and parity are given, along with a brief indication of the method and any reference standard used in the particular measurement. The literature search covers the period to late 2004. Many of the entries prior to 1988 follow those in Raghavan [At. Data Nucl. Data Tables 42 (1989) 189].

Stone, N.J. [Oxford Physics, Clarendon Laboratory, Oxford OX1 3PU (United Kingdom)]. E-mail: n.stone1@physics.oxford.ac.uk

2005-05-01

11

Magnetic dipole and electric dipole resonances in TiO2 microspheres at terahertz frequencies

NASA Astrophysics Data System (ADS)

In a non-magnetic dielectric sphere of high-permittivity (? <20), effective magnetic response occurs as a result of the 1st Mie mode, known as the magnetic dipole resonance. This resonance produces a similar effect as split ring resonators, making it possible to use dielectric spheres as metamaterial components. In the terahertz (THz) part of the spectrum, where dielectrics with ? ~100 can be found, all-dielectric metamaterials can potentially reduce absorption and provide isotropic and polarization-independent properties. In this contribution, we discuss TiO2 micro-spheres, ~1/10 of the wavelength in diameter. Such spheres are expected to support the magnetic and electric dipole resonances. To detect these resonances in a single TiO2 microsphere we use THz near-field microscopy with the sub-wavelength size aperture probe. This method allows detection of Mie resonances in single sub-wavelength spheres. Fano-type line-shape is observed in the near-field amplitude and phase spectra. The narrow line-width of the magnetic resonance and the subwavelength size of the TiO2 microspheres make them excellent candidates for realizing low-loss THz metamaterials.

Mitrofanov, Oleg; Domenic, Filip; Kuel, Petr; Reno, John L.; Brener, Igal; Chung, U.-Chan; Elissalde, Cathy; Maglione, Mario; Mounaix, Patrick

2015-01-01

12

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...

Mansuripur, Masud

2015-01-01

13

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.

Alexander J. Silenko

2007-10-02

14

In this paper we describe a methodology for tailoring the design of metamaterial dielectric resonators, which represent a promising path toward low-loss metamaterials at optical frequencies. We first describe a procedure to decompose the far field scattered by subwavelength resonators in terms of multipolar field components, providing explicit expressions for the multipolar far fields. We apply this formulation to confirm that an isolated high-permittivity cube resonator possesses frequency separated electric and magnetic dipole resonances, as well as a magnetic quadrupole resonance in close proximity to the electric dipole resonance. We then introduce multiple dielectric gaps to the resonator geometry in a manner suggested by perturbation theory, and demonstrate the ability to overlap the electric and magnetic dipole resonances, thereby enabling directional scattering by satisfying the first Kerker condition. We further demonstrate the ability to push the quadrupole resonance away from the degenerate dipole ...

Campione, Salvatore; Warne, Larry K; Sinclair, Michael B

2014-01-01

15

It is shown that in the experiments for search of the EDM of an electron (atom, molecule) the T-odd magnetic moment induced by an electric field and the T-odd electric dipole moment induced by a magnetic field will be also measured. It is discussed how to distinguish these contributions.

Vladimir G. Baryshevsky

2003-11-04

16

Electric dipole moments, cluster metallicity, and the magnetism of rare earth clusters

NASA Astrophysics Data System (ADS)

One of the fundamental properties of bulk metals is the cancellation of electric fields. The free charges inside of a metal will move until they find an arrangement where the internal electric field is zero. This implies that the electric dipole moment of a metal particle should be exactly zero, because an electric dipole moment requires a net separation of charge and thus a nonzero internal electric field. This thesis is an experimental study to see if this property continues to hold for tiny subnanometer metal particles called clusters (2--200 atom, R < 1 nm). We have measured the electric dipole moments of metal clusters made from 15 pure elements using a molecular beam electric deflection technique. We find that the observed dipole moments vary a great deal across the periodic table. Alkali metals have zero dipole moments, while transition metals and lanthanides all have dipole moments which are highly size dependent. In most cases, the measured dipole moments are independent of temperature (T = 20--50 K), and when there is a strong temperature dependence this suggests that there is a new state of matter present. Our interpretation of these results are that those clusters which have a nonzero dipole moment are non-metallic, in the sense that their electrons must be localized and prevented from moving to screen the internal field associated with a permanent dipole moment. This interpretation gives insight to several related phenomena and applications. We briefly discuss an example cluster system RhN where the measured electric dipole moments appear to be correlated with a the N2O reactivity. Finally, we discuss a series of magnetic deflection experiments on lanthanide clusters (Pr, Ho, Tb, and Tm). The magnetic response of these clusters is very complex and highly sensitive to size and temperature. We find that PrN (which is non-magnetic in the bulk) becomes magnetic in clusters and Tm N clusters have magnetic moments lower than the atomic value as well as the bulk saturation value implying that the magnetic order in the cluster involves non-collinear or antiferromagnetic order. HoN and TbN show very similar size dependent trends suggesting that these clusters have similar structures.

Bowlan, John

17

On the radiation Q and the gain of crossed electric and magnetic dipole moments

Exact expressions for the radiation quality factor Q and the gain pattern function of the corresponding antenna are derived and their properties are analyzed for crossed electric and magnetic dipole moment configuration. Both omni-directional and directional antennas with linear, elliptical, or circular polarization can achieve the same minimum radiation Q. The maximum gain of the antenna ranges from 3\\/2 to

Do-Hoon Kwon

2005-01-01

18

The planar quantum dynamics of a neutral particle with a magnetic dipole moment in the presence of electric and magnetic fields is considered. The criteria to establish the planar dynamics reveal that the resulting nonrelativistic Hamiltonian has a simplified expression without making approximations, and some terms have crucial importance for system dynamics.

Edilberto O. Silva

2014-09-28

19

Resonant electric dipole-dipole interactions between cold Rydberg atoms in a magnetic field K electric dipole-dipole interactions between atoms in these two states were probed using the linewidth of the two-photon microwave transition 46d5/2 -47d5/2. The presence of a weak magnetic field 0.5 G reduced

Le Roy, Robert J.

20

NASA Astrophysics Data System (ADS)

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 𝜌𝜌free, electric current-density 𝑱𝑱free, polarization 𝑷𝑷, and magnetization 𝑴𝑴. 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 mediathe seat of the sources of the EM fieldthereby exerting force and torque on these media. In the Lorentz formulation of classical electrodynamics, the electric and magnetic fields, 𝑬𝑬 and 𝑩𝑩, exert forces and torques on electric charge and current distributions. An electric dipole is then modeled as a pair of electric charges on a stick (or spring), and a magnetic dipole is modeled as an Amperian current loop, so that the Lorentz force law can be applied to the corresponding (bound) charges and (bound) currents of these dipoles. In contrast, the Einstein-Laub formulation circumvents the need for specific models of the dipoles by simply providing a recipe for calculating the force- and torque-densities exerted by the 𝑬𝑬 and 𝑯𝑯 fields on charge, current, polarization and magnetization. The two formulations, while similar in many respects, have significant differences. For example, in the Lorentz approach, the Poynting vector is 𝑺𝑺𝐿𝐿 = 𝜇𝜇0 -1𝑬𝑬 × 𝑩𝑩, and the linear and angular momentum densities of the EM field are 𝓹𝓹𝐿𝐿 = 𝜀𝜀0𝑬𝑬 × 𝑩𝑩 and 𝓛𝓛𝐿𝐿 = 𝒓𝒓 × 𝓹𝓹𝐿𝐿, whereas in the Einstein-Laub formulation the corresponding entities are 𝑺𝑺𝐸𝐸𝐸𝐸= 𝑬𝑬 × 𝑯𝑯, 𝓹𝓹𝐸𝐸𝐸𝐸= 𝑬𝑬 × 𝑯𝑯?𝑐𝑐2, and 𝓛𝓛𝐸𝐸𝐸𝐸= 𝒓𝒓 × 𝓹𝓹𝐸𝐸𝐸𝐸. (Here 𝜇𝜇0 and 𝜀𝜀0 are the permeability and permittivity of free space, 𝑐𝑐 is the speed of light in vacuum, 𝑩𝑩 = 𝜇𝜇0𝑯𝑯 + 𝑴𝑴, and 𝒓𝒓 is the position vector.) Such differences can be reconciled by recognizing the need for the so-called hidden energy and hidden momentum associated with Amperian current loops of the Lorentz formalism. (Hidden entities of the sort do not arise in the Einstein-Laub treatment of magnetic dipoles.) Other differences arise from over-simplistic assumptions concerning the equivalence between free charges and currents on the one hand, and their bound counterparts on the other. A more nuanced treatment of EM force and torque densities exerted on polarization and magnetization in the Lorentz approach would help bridge the gap that superficially separates the two formulations. Atoms and molecules may collide with each other and, in general, material constituents can exchange energy, momentum, and angular momentum via direct mechanical interactions. In the case of continuous media, elastic and hydrodynamic stresses, phenomenological forces such as those rela

Mansuripur, Masud

2015-01-01

21

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.

K. Azizi

2009-02-16

22

Interaction between a stationary electric charge and a stationary magnetic dipole

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.

W. B. Bonnor

2002-03-13

23

NASA Technical Reports Server (NTRS)

The generation of ULF waves by ground-based magnetic and electric dipoles is studied with a simplified model consisting of three adjoining homogeneous regions representing the groud, the vacuum (free space) region, and the ionosphere. The system is assumed to be immersed in a homogeneous magnetic field with an arbitrary tilt angle. By the use of Fourier techniques and the method of stationary phase, analytic expressions are obtained for the field strength of the compressional Alfven waves in the ionosphere. Expressions are also obtained for the strength of the torsional Alfven wave in the ionosphere and the ULF magnetic field at ground level. Numerical results are obtained for the compressional Alfven-wave field strength in the ionosphere with a nonvertical geomagnetic field and for the ULF magnetic field at ground level for a vertical geomagnetic field.

Harker, K. J.

1975-01-01

24

Lepton electric and magnetic dipole moments induced by a vector unparticle

NASA Astrophysics Data System (ADS)

We calculate the magnetic dipole moment (MDM) and the electric dipole moment (EDM) of a lepton induced by a vector unparticle with both vector and axial-vector couplings to leptons. We consider the most general scenario in which the unparticle induces lepton flavor violation (LFV) and CP violation. Some specific scenarios are examined to obtain constraints on the LFV unparticle couplings from the current limits on the muon MDM and the decay ? ? 3?. While the experimental limit on the muon MDM favor the scenario in which there is dominance of the unparticle vector couplings over the axial-vector couplings, the experimental limit on the ? ? 3? decay strongly constraints the unparticle LFV couplings. We use these constraints to estimate the EDMs of the electron and the muon, which are negligible and far from the current experimental limits.

Moyotl, A.; Rosado, A.; Tavares-Velasco, G.

2012-08-01

25

Trapped and Bound Classical States of an Electric Dipole in Magnetic Field

In the present work, we study the classical behavior of an electric dipole in presence of an external uniform magnetic field. We derive equations and constants of motion from the Lagrangian formulation. We obtain an infinitely periodic effective potential that describes a rotational motion. The problem is not directly separable in relative and center of mass variables; even though, we are able to write the energy of the system as a function of an only term, the relative variable. We define another constant of motion, which couples the relative with the center of mass variables. We describe conditions for bound states of the dipole. In addition, we discuss the problem in the approximation of small oscillations. Finally, we explore the existence of a possible family of trapped states in a region of the space where there are no classical turning points.

Paulina I. Troncoso; Sergio Curilef

2006-07-06

26

Measurement of the anomalous magnetic and electric dipole moments of the tau lepton

We analyse e+e????? events using 100pb?1 of data collected by the L3 experiment during the 1991-1995 LEP runs at the Z pole. From the energy of the photons and their isolation from the tau decay products, we determine the anomalous magnetic and electric dipole moments of the tau to be, respectively:a?=0.004ħ0.027ħ0.023;d?=(0.0ħ1.5ħ1.3)×10?16e·cm.This is a direct measurement of these ? form factors

M. Acciarri; O. Adriani; M. Aguilar-Benitez; S P Ahlen; J. Alcaraz; G. Alemanni; James V Allaby; A. Aloisio; M. G. Alviggi; H. Anderhub; V. P. Andreev; T. Angelescu; F. Anselmo; A. Arefiev; T. Azemoon; P. Bagnaia; L. Baksay; R. C. Ball; S. Banerjee; K. Banicz; A. Barczyk; R. Barillère; L. Barone; P. Bartalini; A. Baschirotto; M. Basile; R. Battiston; A. Bay; F. Becattini; U. Becker; F. Behner; J. Berdugo; P. Berges; B. Bertucci; S. Bhattacharya; M. Biasini; A. Biland; G. M. Bilei; J. J. Blaising; S. C. Blyth; G. J. Bobbink; R. Bock; A. Böhm; L. Boldizsar; B. Borgia; D. Bourilkov; M. Bourquin; D. Boutigny; S. Braccini; J. G. Branson; V. Brigljevic; I. C. Brock; A. Buffini; J. D. Burger; W. J. Burger; X. D. Cai; M. Campanelli; G. Cara Romeo; A. M. Cartacci; J. Casaus; G. Castellini; F. Cavallari; N. Cavallo; C. Cecchi; M. Cerrada; F. Cesaroni; M. Chamizo; Y. H. Chang; U. K. Chaturvedi; S. V. Chekanov; M. Chemarin; A. Chen; G M Chen; H. F. Chen; H. S. Chen; M. Chen; G. Chiefari; C. Y. Chien; L. Cifarelli; F. Cindolo; C. Civinini; I. Clare; G. Coignet; A. P. Colijn; N. Colino; S. Costantini; F. Cotorobai; B. de la Cruz; A. Csilling; T. S. Dai; R. D'Alessandro; R. de Asmundis; A. Degré; K. Deiters; P. Denes; F. DeNotaristefani; M. Diemoz; D. van Dierendonck; F. Di Lodovico; C. Dionisi; M. Dittmar; A. Dominguez; M. T. Dova; E. Drago; D. Duchesneau; P. Duinker; I. Duran; S. Easo; H. El Mamouni; A. Engler; F. J. Eppling; F. C. Erné; J. P. Ernenwein; M A Falagán; R. Faccini; S. Falciano; A. Favara; J. Fay; O. Fedin; M. Felcini; T. Ferguson; F. Ferroni; H. Fesefeldt; E. Fiandrini; J. H. Field; F. Filthaut; P. H. Fisher; I. Fisk; G. Forconi; L. Fredj; K. Freudenreich; C. Furetta; Yu. Galaktionov; S. N. Ganguli; P. Garcia-Abia; M. Gataullin; S. S. Gau; S. Gentile; J. Gerald; N. Gheordanescu; S. Giagu; S. Goldfarb; J. Goldstein; Z. F. Gong; A. Gougas; G. Gratta; M. W. Gruenewald; R. van Gulik; V. K. Gupta; A. Gurtu; L. J. Gutay; D. Haas; B. Hartmann; A. Hasan; D. Hatzifotiadou; T. Hebbeker; A. Hervé; P. Hidas; J. Hirschfelder; W. C. van Hoek; H. Hofer; H. Hoorani; S. R. Hou; G. Hu; I. Iashvili; B. N. Jin; L. W. Jones; P. de Jong; I. Josa-Mutuberria; A. Kasser; R. A. Khan; D. Kamrad; J. S. Kapustinsky; Y. Karyotakis; M. Kaur; M. N. Kienzle-Focacci; D. Kim; J. K. Kim; S. C. Kim; W. W. Kinnison; A. Kirkby; D. Kirkby; J. Kirkby; D. Kiss; W. Kittel; A. Klimentov; A. Kopp; I. Korolko; V. Koutsenko; R. W. Kraemer; A. Kunin; P. Lacentre; P. Ladron de Guevara; G. Landi; C. Lapoint; K. Lassila-Perini; P. Laurikainen; A. Lavorato; M. Lebeau; A. Lebedev; P. Lebrun; P. Lecomte; P. Le Coultre; H. J. Lee; C. Leggett; J. M. Le Goff; R. Leiste; E. Leonardi; P. Levtchenko; C. Li; C. H. Lin; W. T. Lin; F. L. Linde; Z. A. Liu; W. Lohmann; E. Longo; W. Lu; Y. S. Lu; K. Lübelsmeyer; C. Luci; D. Luckey; L. Luminari; W. Lustermann; W. G. Ma; M. Maity; G. Majumder; L. Malgeri; A. Malinin; C. Maña; D. Mangeol; P. Marchesini; G. Marian; A. Marin; J. P. Martin; F. Marzano; G. G. G. Massaro; K. Mazumdar; S. Mele; L. Merola; M Von der Mey; W. J. Metzger; Y. Mi; D. Migani; A. Mihul; A. J. W. van Mil; H. Milcent; G. Mirabelli; J. Mnich; P. Molnar; B. Monteleoni; R. Moore; T. Moulik; R. Mount; F. Muheim; A. J. M. Muijs; S. Nahn; M. Napolitano; F. Nessi-Tedaldi; H. Newman; T. Niessen; A. Nippe; A. Nisati; H. Nowak; Y. D. Oh; G. Organtini; R. Ostonen; S. Palit; C. Palomares; D. Pandoulas; S. Paoletti; P. Paolucci; H. K. Park; I. H. Park; G. Pascale; G. Passaleva; S. Patricelli; T. Paul; M. Pauluzzi; C. Paus; F. Pauss; D. Peach; Y. J. Pei; S. Pensotti; D. Perret-Gallix; B. Petersen; S. Petrak; A. Pevsner; D. Piccolo; M. Pieri; P. A. Piroué; E. Pistolesi; V Pozhidaev; M. Pohl; V. Pojidaev; H. Postema; J. Pothier; N. Produit; D. Prokofiev; J. Quartieri; G. Rahal-Callot; N. Raja; P. G. Rancoita; M. Rattaggi; G. Raven; P. Razis; D. Ren; M. Rescigno; S. Reucroft; T. van Rhee; S. Riemann; K. Riles; O. Rind; A. Robohm; J. Rodin; B. P. Roe; L. Romero; S. Rosier-Lees; Ph. Rosselet; S. Roth; J. A. Rubio; D. Ruschmeier; H. Rykaczewski; J. Salicio; E. Sanchez; M E Sarakinos; G. Sauvage; C. Schäfer; V. Schegelsky; S. Schmidt-Kaerst; D. Schmitz; M. Schneegans; N. Scholz; H. Schopper; D. J. Schotanus; G. Schwering; C. Sciacca; D. Sciarrino; L. Servoli; S. Shevchenko; N. Shivarov; V. Shoutko; J. Shukla; E. Shumilov; A. Shvorob; T. Siedenburg; D. Son; V. Soulimov; B. Smith; P. Spillantini; M. Steuer; D. P. Stickland; H. Stone; B. Stoyanov; A. Straessner; K. Sudhakar; G. Sultanov; L. Z. Sun; G. F. Susinno; H. Suter; J. D. Swain; X. W. Tang; L. Tauscher; Samuel C. C. Ting; S. M. Ting; S. C. Tonwar; J. Tóth; C. Tully; K. L. Tung; Y. Uchida; J. Ulbricht; E. Valente; G. Vesztergombi; I. Vetlitsky; G. Viertel; M. Vivargent; S. Vlachos; H. Vogel; H. Vogel; I. Vorobiev; A. A. Vorobyov; M. Wadhwa; W. Wallraff; J. C. Wang; X. L. Wang

1998-01-01

27

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.

A. J. Silenko

2006-02-03

28

Magnetic and electric dipole moments of the H {sup 3}{Delta}{sub 1} state in ThO

The metastable H {sup 3}{Delta}{sub 1} state in the thorium monoxide (ThO) molecule is highly sensitive to the presence of a CP-violating permanent electric dipole moment of the electron (eEDM) [E. R. Meyer and J. L. Bohn, Phys. Rev. A 78, 010502 (2008)]. The magnetic dipole moment {mu}{sub H} and the molecule-fixed electric dipole moment D{sub H} of this state are measured in preparation for a search for the eEDM. The small magnetic moment {mu}{sub H}=8.5(5)x10{sup -3} {mu}{sub B} displays the predicted cancellation of spin and orbital contributions in a {sup 3}{Delta}{sub 1} paramagnetic molecular state, providing a significant advantage for the suppression of magnetic field noise and related systematic effects in the eEDM search. In addition, the induced electric dipole moment is shown to be fully saturated in very modest electric fields (<10 V/cm). This feature is favorable for the suppression of many other potential systematic errors in the ThO eEDM search experiment.

Vutha, A. C.; Kirilov, E.; DeMille, D. [Department of Physics, Yale University, New Haven, Connecticut 06520 (United States); Spaun, B.; Gurevich, Y. V.; Hutzler, N. R.; Doyle, J. M.; Gabrielse, G. [Department of Physics, Harvard University, Cambridge, Massachusetts 02138 (United States)

2011-09-15

29

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.

Afach, S; Ban, G; Bison, G; Bodek, K; Chowdhuri, Z; Daum, M; Fertl, M; Franke, B; Geltenbort, P; Green, K; van der Grinten, M G D; Grujic, Z; Harris, P G; Heil, W; Hélaine, V; Henneck, R; Horras, M; Iaydjiev, P; Ivanov, S N; Kasprzak, M; Kermaïdic, Y; Kirch, K; Knowles, P; Koch, H -C; Komposch, S; Kozela, A; Krempel, J; Lauss, B; Lefort, T; Lemière, Y; Mtchedlishvili, A; Naviliat-Cuncic, O; Pendlebury, J M; Piegsa, F M; Pignol, G; Prashant, P N; Quéméner, G; Rebreyend, D; Ries, D; Roccia, S; Schmidt-Wellenburg, P; Severijns, N; Weis, A; Wursten, E; Wyszynski, G; Zejma, J; Zenner, J; Zsigmond, G

2015-01-01

30

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.

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

2015-03-30

31

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.

B. Plaster

2013-09-22

32

Using the interaction $Q \\\\cdot Q ~+~ xV_{S.O.}$ where $V_{S.O.}$ is a two-body spin-orbit interaction, we study the effects of varying x on the static electric quadrupole and magnetic dipole moments of the $2^+_1$ and $2^+_2$ states of $^{10}Be$. This is done both in the valence space $s^4p^6$ and in a larger space in which 2 $\\\\hbar \\\\omega$ excitations are

S. Aroua; L. Zamick; M. S. Fayache

2000-01-01

33

The relaxation rates of the monopole, magnetic dipole, and electric quadrupole moments have been determined for the 3Âı{ital P} state of helium excited by electron impact, The data are determined from atomic lifetimes using linear and circular polarization analyzed radiation with the electron-photon delayed coincidence technique. This has permitted the direct observation of the time dependence of all the off-diagonal

J. F. Williams; A. G. Mikosza; J. B. Wang; A. B. Wedding

1992-01-01

34

The relaxation rates of the monopole, magnetic dipole, and electric quadrupole moments have been determined for the 31P state of helium excited by electron impact, The data are determined from atomic lifetimes using linear and circular polarization analyzed radiation with the electron-photon delayed coincidence technique. This has permitted the direct observation of the time dependence of all the off-diagonal elements

J. F. Williams; A. G. Mikosza; J. B. Wang; A. B. Wedding

1992-01-01

35

The possibility of nonnegligible W electric dipole (muW) and magnetic quadrupole ( Qtilde W) moments induced by the most general HWW vertex is examined via the effective Lagrangian technique. It is assumed that new heavy fermions induce an anomalous CP-odd component of the HWW vertex, which can be parametrized by an SUL(2)×UY(1)-invariant dimension-six operator. This anomalous contribution, when combined with

J. Montaño; F. Ramírez-Zavaleta; G. Tavares-Velasco; J. J. Toscano

2005-01-01

36

Lithium electric dipole polarizability

The electric dipole polarizability of the lithium atom in the ground state is calculated including relativistic and quantum electrodynamics corrections. The obtained result {alpha}{sub E}=164.0740(5) a.u. is in good agreement with the less accurate experimental value of 164.19(1.08) a.u. The small uncertainty of about 3 parts per 10{sup 6} comes from the approximate treatment of quantum electrodynamics corrections. Our theoretical result can be considered as a benchmark for more general atomic structure methods and may serve as a reference value for the relative measurement of polarizabilities of the other alkali-metal atoms.

Puchalski, M.; KePdziera, D.; Pachucki, K. [Faculty of Chemistry, Adam Mickiewicz University, Grunwaldzka 6, PL-60-780 Poznan (Poland); Faculty of Chemistry, Nicolaus Copernicus University, Gagarina 7, PL-87-100 Torun (Poland); Faculty of Physics, University of Warsaw, Hoza 69, PL-00-681 Warsaw (Poland)

2011-11-15

37

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.

S. J. Brodsky; S. Gardner; D. S. Hwang

2006-02-27

38

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

39

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.; /SLAC; Gardner, Susan; /Kentucky U.; Hwang, Dae Sung; /Sejong U.

2006-01-11

40

The Surrounding Field Compensation (SFC) system described in this work is installed around the four-layer Mu-metal magnetic shield of the neutron electric dipole moment spectrometer located at the Paul Scherrer Institute. The SFC system reduces the DC component of the external magnetic field by a factor of about 20. Within a control volume of approximately 2.5?m?×?2.5?m?×?3?m, disturbances of the magnetic field are attenuated by factors of 550 at a bandwidth from 10{sup ?3} Hz up to 0.5?Hz, which corresponds to integration times longer than several hundreds of seconds and represent the important timescale for the neutron electric dipole moment measurement. These shielding factors apply to random environmental noise from arbitrary sources. This is achieved via a proportional-integral feedback stabilization system that includes a regularized pseudoinverse matrix of proportionality factors which correlates magnetic field changes at all sensor positions to current changes in the SFC coils.

Afach, S.; Fertl, M.; Franke, B., E-mail: beatrice.franke@psi.ch, E-mail: bernhard.lauss@psi.ch; Kirch, K. [Paul Scherrer Institute, Villigen (Switzerland); Institute for Particle Physics, Eidgenössische Technische Hochschule, Zürich (Switzerland); Bison, G.; Burri, F.; Chowdhuri, Z.; Daum, M.; Henneck, R.; Lauss, B., E-mail: beatrice.franke@psi.ch, E-mail: bernhard.lauss@psi.ch; Meier, M.; Schmidt-Wellenburg, P.; Zsigmond, G. [Paul Scherrer Institute, Villigen (Switzerland); Bodek, K.; Zejma, J. [Jagellonian University, Cracow (Poland); Grujic, Z.; Kasprzak, M.; Weis, A. [University of Fribourg (Switzerland); Hélaine, V. [Laboratoire de Physique Corpusculaire, Caen (France); Paul Scherrer Institute, Villigen (Switzerland); Koch, H.-C. [Institut für Physik, Johannes-Gutenberg-Universität, Mainz (Germany); University of Fribourg (Switzerland); and others

2014-08-28

41

NASA Astrophysics Data System (ADS)

The Surrounding Field Compensation (SFC) system described in this work is installed around the four-layer Mu-metal magnetic shield of the neutron electric dipole moment spectrometer located at the Paul Scherrer Institute. The SFC system reduces the DC component of the external magnetic field by a factor of about 20. Within a control volume of approximately 2.5 m × 2.5 m × 3 m, disturbances of the magnetic field are attenuated by factors of 5-50 at a bandwidth from 10 - 3 Hz up to 0.5 Hz, which corresponds to integration times longer than several hundreds of seconds and represent the important timescale for the neutron electric dipole moment measurement. These shielding factors apply to random environmental noise from arbitrary sources. This is achieved via a proportional-integral feedback stabilization system that includes a regularized pseudoinverse matrix of proportionality factors which correlates magnetic field changes at all sensor positions to current changes in the SFC coils.

Afach, S.; Bison, G.; Bodek, K.; Burri, F.; Chowdhuri, Z.; Daum, M.; Fertl, M.; Franke, B.; Grujic, Z.; Hélaine, V.; Henneck, R.; Kasprzak, M.; Kirch, K.; Koch, H.-C.; Kozela, A.; Krempel, J.; Lauss, B.; Lefort, T.; Lemière, Y.; Meier, M.; Naviliat-Cuncic, O.; Piegsa, F. M.; Pignol, G.; Plonka-Spehr, C.; Prashanth, P. N.; Quéméner, G.; Rebreyend, D.; Roccia, S.; Schmidt-Wellenburg, P.; Schnabel, A.; Severijns, N.; Voigt, J.; Weis, A.; Wyszynski, G.; Zejma, J.; Zenner, J.; Zsigmond, G.

2014-08-01

42

CrRb: A molecule with large magnetic and electric dipole moments

We report calculations of Born-Oppenheimer potential energy curves of the chromium-rubidium heteronuclear molecule ({sup 52}Cr{sup 87}Rb), and the long-range dispersion coefficient for the interaction between ground state Cr and Rb atoms. Our calculated van der Waals coefficient (C{sub 6}=1770 a.u.) has an expected error of 3%. The ground state {sup 6{Sigma}+} molecule at its equilibrium separation has a permanent electric dipole moment of d{sub e}(R{sub e}=3.34Angstrom)=2.90 D. We investigate the hyperfine and dipolar collisions between trapped Cr and Rb atoms, finding elastic to inelastic cross section ratio of 10{sup 2}-10{sup 3}.

Pavlovic, Z. [ITAMP, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States); Department of Physics, University of Connecticut, Storrs, Connecticut 06269-3046 (United States); Sadeghpour, H. R. [ITAMP, Harvard-Smithsonian Center for Astrophysics, 60 Garden Street, Cambridge, Massachusetts 02138 (United States); Cote, R. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269-3046 (United States); Roos, B. O. [Department of Theoretical Chemistry, University of Lund, S-221 00 Lund (Sweden)

2010-05-15

43

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.

A. L. Barabanov; R. Golub; S. K. Lamoreaux

2005-12-20

44

NASA Technical Reports Server (NTRS)

With the use of a power integral formulation, a study is made of the vlf/elf radiation patterns of arbitrarily oriented electric and magnetic dipoles in a cold lossless multicomponent magnetoplasma. Expressions for the ray patterns are initially developed that apply for arbitrary values of driving frequency, static magnetic-field strength, plasma density, and composition. These expressions are subsequently specialized to vlf/elf radiation in a plasma modeled on the magnetosphere. A series of representative pattern plots are presented for frequencies between the proton and electron gyrofrequencies. These patterns illustrate the fact that focusing effects that arise from the geometrical properties of the refractive index surface tend to dominate the radiation distribution over the entire range from the electron gyrofrequency to 4.6 times the proton gyrofrequency. It is concluded that focusing effects should be of significant importance in the design of a vlf/elf satellite transmitting system in the magnetosphere.

Wang, T. N. C.; Bell, T. F.

1972-01-01

45

Electric Dipole Moments of Dyon and `Electron'

The electric and magnetic dipole moments of dyon fermions are calculated within N=2 supersymmetric Yang-Mills theory including the theta-term. It is found, in particular, that the gyroelectric ratio deviates from the canonical value of 2 for the monopole fermion (n_m=1,n_e=0) in the case theta\

Makoto Kobayashi; Taichiro Kugo; Tatsuya Tokunaga

2008-01-08

46

Time-resolved energy-momentum spectroscopy of electric and magnetic dipole transitions in Cr3+:MgO.

Due to the recent interest in magnetic light-matter interactions, the magnetic dipole (MD) transitions in lanthanide ions have been studied for potential applications in nano-optics. Similar to lanthanide ions, transition-metal ions also exhibit strong MD emission at room temperature, but their prominent MD zero-phonon lines are often accompanied by significant electric dipole (ED) sideband emission. Here, we extend energy-momentum spectroscopy to time-resolved measurements, and use this technique to quantify the ED and MD contributions to light emission from trivalent chromium doped magnesium oxide (Cr(3+):MgO). This allows us to differentiate the MD (2)E ? (4)A2 zero-phonon line from phonon-assisted (2)E ? (4)A2 and (4)T2 ? (4)A2 ED sidebands. We also demonstrate how the relative intensities of the sharp MD zero-phonon line and the broad ED sidebands can be used as a qualitative measure of the MD and ED local density of optical states. PMID:23879390

Karaveli, Sinan; Wang, Shutong; Xiao, Gang; Zia, Rashid

2013-08-27

47

Multiferroics, showing simultaneous ordering of electrical and magnetic degrees of freedom, are remarkable materials as seen from both the academic and technological points of view. A prominent mechanism of multiferroicity is the spin-driven ferroelectricity, often found in frustrated antiferromagnets with helical spin order. There, as for conventional ferroelectrics, the electrical dipoles arise from an off-centre displacement of ions. However, recently a different mechanism, namely purely electronic ferroelectricity, where charge order breaks inversion symmetry, has attracted considerable interest. Here we provide evidence for ferroelectricity, accompanied by antiferromagnetic spin order, in a two-dimensional organic charge-transfer salt, thus representing a new class of multiferroics. We propose a charge-order-driven mechanism leading to electronic ferroelectricity in this material. Quite unexpectedly for electronic ferroelectrics, dipolar and spin order arise nearly simultaneously. This can be ascribed to the loss of spin frustration induced by the ferroelectric ordering. Hence, here the spin order is driven by the ferroelectricity, in marked contrast to the spin-driven ferroelectricity in helical magnets. PMID:22886065

Lunkenheimer, Peter; Müller, Jens; Krohns, Stephan; Schrettle, Florian; Loidl, Alois; Hartmann, Benedikt; Rommel, Robert; de Souza, Mariano; Hotta, Chisa; Schlueter, John A; Lang, Michael

2012-09-01

48

Multiferroics, showing simultaneous ordering of electrical and magnetic degrees of freedom, are remarkable materials as seen from both the academic and technological points of view. A prominent mechanism of multiferroicity is the spin-driven ferroelectricity, often found in frustrated antiferromagnets with helical spin order. There, as for conventional ferroelectrics, the electrical dipoles arise from an off-centre displacement of ions. However, recently a different mechanism, namely purely electronic ferroelectricity, where charge order breaks inversion symmetry, has attracted considerable interest. Here we provide evidence for ferroelectricity, accompanied by antiferromagnetic spin order, in a two-dimensional organic charge-transfer salt, thus representing a new class of multiferroics. We propose a charge-order-driven mechanism leading to electronic ferroelectricity in this material. Quite unexpectedly for electronic ferroelectrics, dipolar and spin order arise nearly simultaneously. This can be ascribed to the loss of spin frustration induced by the ferroelectric ordering. Hence, here the spin order is driven by the ferroelectricity, in marked contrast to the spin-driven ferroelectricity in helical magnets.

Lunkenheimer, P.; Muller, J.; Krohns, S.; Schrettle, F.; Loidl, A.; Hartmann, B.; Rommel, R.; de Souza, M.; Hotta, C.; Schlueter, J. A.; Lang, M. (Materials Science Division); (Univ. Augsburg); (Goethe-Univ. Frankfurt); (Kyoto Sangyo Univ.)

2012-01-01

49

Electric dipole two equal magnitude,

Electric dipole two equal magnitude, opposite charged particles separated by distance d What) directions =-=-= 9090 sin dpEdWU Ep·-=-= cospEU #12;Exercise Rank a) magnitude of torque and b) U , greatest to least a) Magnitudes are same U greatest at =180 b) 1 & 3 tie, then 2 &4 sinpE=×= Ep cosp

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

50

Dipole relaxation in an electric field

NASA Astrophysics Data System (ADS)

From Boltzmann's equation, S=k ln?, an expression for the orientational entropy, S of a rigid rod (electric dipole) is derived. The free energy of the dipole in an electric field is then calculated as a function of both the dipole's average orientation and the field strength. Application of the equilibrium criterion to the free energy yields the field dependence of the entropy of the dipole. Irreversible thermodynamics is used to derive the general form of the equation of motion of the dipole's average orientation. Subsequent application of Newton's second law of motion produces Debye's classical expression for the relaxation of an electric dipole in a viscous medium.

Neumann, Richard M.

1980-07-01

51

Using the interaction $Q \\cdot Q ~+~ xV_{S.O.}$ where $V_{S.O.}$ is a two-body spin-orbit interaction, we study the effects of varying x on the static electric quadrupole and magnetic dipole moments of the $2^+_1$ and $2^+_2$ states of $^{10}Be$. This is done both in the valence space $s^4p^6$ and in a larger space in which 2 $\\hbar \\omega$ excitations are allowed. In the former case, for x=0, we have the Wigner Supermultiplet limit in which the $2^+_1$ and $2^+_2$ states are degenerate and correspond to K=0 and K=2 rotational states, with equal and opposite static quadrupole moments. Turning on the spin-orbit interaction with sufficient strength in the valence space gives an energy splitting to the two $2^+$ states in accord with experiment. When higher shell admixtures are allowed, we get quite a different behaviour as a function of x than in the valence space. Of particular interest is a value of x for which $Q(2^+_1)$ and $Q(2^+_2)$ both nearly vanish, and so does (somewhat coincidentally) $\\mu(2^+_1)$.

S. Aroua; L. Zamick; M. S. Fayache

2000-11-01

52

Magnetic-dipole photo-recombination in ultracold hydrogen plasma

NASA Astrophysics Data System (ADS)

The cross section for magnetic-dipole photodisintegration of the negative hydrogen ion has been calculated within the zero-range-potential approximation. The magnetic-dipole cross section for photodetachment within the very narrow range of energy near the process threshold is predicted to dominate over the electric-dipole one. It is shown that in ultracold hydrogen plasma at temperatures below T = 3.29 × 10-4 K the magnetic-dipole photo-recombination becomes an important mechanism of electron capture by hydrogen atoms.

Baltenkov, A. S.

2014-05-01

53

Measuring the Forces between Magnetic Dipoles

ERIC Educational Resources Information Center

We describe a simple undergraduate lab in which students determine how the force between two magnetic dipoles depends on their separation. We consider the case where both dipoles are permanent and the case where one of the dipoles is induced by the field of the other (permanent) dipole. Agreement with theoretically expected results is quite good.

Gayetsky, Lisa E.; Caylor, Craig L.

2007-01-01

54

Magnetic field modification of optical magnetic dipoles.

Acting on optical magnetic dipoles opens novel routes to govern light-matter interaction. We demonstrate magnetic field modification of the magnetic dipolar moment characteristic of resonant nanoholes in thin magnetoplasmonic films. This is experimentally shown through the demonstration of the magneto-optical analogue of Babinet's principle, where mirror imaged MO spectral dependencies are obtained for two complementary magnetoplasmonic systems: holes in a perforated metallic layer and a layer of disks on a substrate. PMID:25646869

Armelles, Gaspar; Caballero, Blanca; Cebollada, Alfonso; Garcia-Martin, Antonio; Meneses-Rodríguez, David

2015-03-11

55

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.

Authors A. L. Barabanov; R. Golub; S. K. Lamoreaux

2006-07-17

56

Electric dipoles on the Bloch sphere

NASA Astrophysics Data System (ADS)

The time evolution of a two-level quantum mechanical system can be geometrically described using the Bloch sphere. By mapping the Bloch sphere evolution onto the dynamics of oscillating electric dipoles, we provide a physically intuitive link between classical electromagnetism and the electric dipole transitions of atomic and molecular physics.

Vutha, Amar C.

2015-03-01

57

Magnetic Field of a Dipole and the Dipole-Dipole Interaction

ERIC Educational Resources Information Center

With a data-acquisition system and sensors commercially available, it is easy to determine magnetic fields produced by permanent magnets and to study the dipole-dipole interaction for different separations and angular positions of the magnets. For sufficiently large distances, the results confirm the 1/R[superscript 3] law for the magnetic field

Kraftmakher, Yaakov

2007-01-01

58

Magnetic dipole discharges. III. Instabilities

Instabilities in a cross-field discharge around a permanent magnet have been investigated. The permanent magnet serves as a cold cathode and the chamber wall as an anode. The magnet is biased strongly negative and emits secondary electrons due to impact of energetic ions. The electrons outside the sheath are confined by the strong dipolar magnetic field and by the ion-rich sheath surrounding the magnet. The electron energy peaks in the equatorial plane where most ionization occurs and the ions are trapped in a negative potential well. The discharge mechanism is the same as that of cylindrical and planar magnetrons, but here extended to a 3-D cathode geometry using a single dipole magnet. While the basic properties of the discharge are presented in a companion paper, the present focus is on various observed instabilities. The first is an ion sheath instability which oscillates the plasma potential outside the sheath below the ion plasma frequency. It arises in ion-rich sheaths with low electron supply, which is the case for low secondary emission yields. Sheath oscillations modulate the discharge current creating oscillating magnetic fields. The second instability is current-driven ion sound turbulence due to counter-streaming electrons and ions. The fluctuations have a broad spectrum and short correlation lengths in all directions. The third type of fluctuations is spiky potential and current oscillations in high density discharges. These appear to be due to unstable emission properties of the magnetron cathode.

Stenzel, R. L.; Urrutia, J. M. [Department of Physics and Astronomy, University of California Los Angeles, California 90095-1547 (United States)] [Department of Physics and Astronomy, University of California Los Angeles, California 90095-1547 (United States); Ionita, C.; Schrittwieser, R. [Institute for Ion Physics and Applied Physics, University of Innsbruck A-6020 Innsbruck (Austria)] [Institute for Ion Physics and Applied Physics, University of Innsbruck A-6020 Innsbruck (Austria)

2013-08-15

59

Magnetic dipole discharges. III. Instabilities

NASA Astrophysics Data System (ADS)

Instabilities in a cross-field discharge around a permanent magnet have been investigated. The permanent magnet serves as a cold cathode and the chamber wall as an anode. The magnet is biased strongly negative and emits secondary electrons due to impact of energetic ions. The electrons outside the sheath are confined by the strong dipolar magnetic field and by the ion-rich sheath surrounding the magnet. The electron energy peaks in the equatorial plane where most ionization occurs and the ions are trapped in a negative potential well. The discharge mechanism is the same as that of cylindrical and planar magnetrons, but here extended to a 3-D cathode geometry using a single dipole magnet. While the basic properties of the discharge are presented in a companion paper, the present focus is on various observed instabilities. The first is an ion sheath instability which oscillates the plasma potential outside the sheath below the ion plasma frequency. It arises in ion-rich sheaths with low electron supply, which is the case for low secondary emission yields. Sheath oscillations modulate the discharge current creating oscillating magnetic fields. The second instability is current-driven ion sound turbulence due to counter-streaming electrons and ions. The fluctuations have a broad spectrum and short correlation lengths in all directions. The third type of fluctuations is spiky potential and current oscillations in high density discharges. These appear to be due to unstable emission properties of the magnetron cathode.

Stenzel, R. L.; Urrutia, J. M.; Ionita, C.; Schrittwieser, R.

2013-08-01

60

Deriving the static interaction between electric dipoles via the quantum gauge transformation

Gauge transformation leaves the electric and the magnetic fields unchanged as long as the gauge function is treated classically. In this paper we consider the gauge transformation commonly used to obtain the electric dipole interaction Hamiltonian in a system of dipoles and the electromagnetic field (Goeppert-Mayer transformation) and treat the vector potential that appear in the gauge function as an operator. While it modifies the electric field, the static interaction between the dipoles is derived.

Makoto Morinaga

2013-02-14

61

Capacitive Stress Transducers in Model Dipole Magnets

Capacitive stress transducers are used to measure mechanical stresses in the windings of superconducting dipole magnets. These transducers consist of a bonded laminate composed of alternating foils of stainless steel and a high-strength polymer...

Benson, Christopher P.

2010-07-14

62

SSC collider dipole magnet end mechanical design

This paper describes the mechanical design of the ends of Superconducting Super Collider dipole magnets to be constructed and tested at Fermilab. Coil end clamps, end yoke configuration, and end plate design are discussed. Loading of the end plate by axial Lorentz forces is discussed. Relevant data from 40 mm and 50 mm aperture model dipole magnets built and tested at Fermilab are presented. In particular, the apparent influence of end clamp design on the quench behavior of model SSC dipoles is described. 8 refs., 3 figs.

Delchamps, S.W.; Bossert, R.C.; Carson, J.; Ewald, K.; Fulton, H.; Kerby, J.; Koska, W.; Strait, J.; Wake, S.M. (Fermi National Accelerator Lab., Batavia, IL (USA)); Leung, K.K. (Superconducting Super Collider Lab., Dallas, TX (USA))

1991-05-01

63

Neutron Electric Dipole Moment Matt Eichenfield

Neutron Electric Dipole Moment (NEDM) Matt Eichenfield 04/20/2007 #12;P and T Violations EDM to explain the Baryonic asymmetry of the universe #12;The Neutron's Constituents Three quarks Two down (q d neutron radius, the separation causing the SM NEDM

Golwala, Sunil

64

Specifically supersymmetric contribution to electric dipole moments

We discuss a source of CP violation which is specific to supersymmetric theories. CP violating phases appear in the mass matrix of the gauge and Higgs fermions. We estimate its effect on the electric dipole moment of the electron and the neutron. Their magnitude is found to be close to the experimental upper bounds.

F. del Águila; M. B. Gavela; J. A. Grifols; A. Méndez

1983-01-01

65

Calculations of atomic electric dipole moments

The ratio of the atomic electric dipole moment (EDM) to a possible electron EDM has been calculated for the ground states of Cs, Xe and Hg, including to all orders the diagrams that involve only single excitations, while neglecting correlation effects, which require the simultaneous excitation of two or more electrons. The alkali atoms are known to have large enhancement

Ann-Marie Mċrtensson-Pendrill; Per Öster

1987-01-01

66

Limit on the Electron Electric Dipole Moment in Gadolinium-Iron Garnet

A new method for the detection of the electron electric dipole moment (EDM) using a solid is described. The method involves the measurement of a voltage induced across the solid by the alignment of the sample's magnetic dipoles in an applied magnetic field, H. A first application of the method to GdIG has resulted in a limit on the electron

B. J. Heidenreich; O. T. Elliott; N. D. Charney; K. A. Virgien; A. W. Bridges; M. A. McKeon; S. K. Peck; D. Krause Jr.; J. E. Gordon; L. R. Hunter; S. K. Lamoreaux

2005-01-01

67

The electric dipole response of $^{76}$Se

The dipole response of $^{76}_{34}$Se in the energy range 4 to 9 MeV has been analyzed using a $(\\vec\\gamma,{\\gamma}')$ polarized photon scattering technique, performed at the High Intensity $\\gamma$-Ray Source facility, to complement previous work performed using unpolarized photons. The results of this work offer both an enhanced sensitivity scan of the dipole response and an unambiguous determination of the parities of the observed J=1 states. The dipole response is found to be dominated by $E1$ excitations, and can reasonably be attributed to a pygmy dipole resonance. Evidence is presented to suggest that a significant amount of directly unobserved excitation strength is present in the region, due to unobserved branching transitions in the decays of resonantly excited states. The dipole response of the region is severely underestimated when considering only ground state decay branches. We investigate the electric dipole response theoretically, performing calculations in a 3D cartesian-basis time-dependent...

Goddard, P M; Werner, V; Rusev, G; Stevenson, P D; Rios, A; Bernards, C; Chakraborty, A; Crider, B P; Kelley, J H; Kwan, E; Glorius, J; Peters, E E; Pietralla, N; Raut, R; Romig, C; Savran, D; Schnorrenberger, L; Smith, M K; Sonnabend, K; Tonchev, A P; Tornow, W; Yates, S W

2013-01-01

68

Permanent Electric Dipole Moment of Cerium Monoxide

NASA Astrophysics Data System (ADS)

Stark spectra of the [16.5]2-X12 and [16.5]2-X23 transitions of cerium monoxide (CeO) have been obtained at a resolution of 50 MHz. Analysis of the Stark spectra yielded permanent electric dipole moments, ?el, of 3.119(8), 3.115(7), and 2.119(8) D for the X12, X23, and [16.5]2 states, respectively. The ground X12 state dipole moment is shown to follow the trend shown by other lanthanide oxides. While most ab initio calculations tend to overestimate the ground state dipole moment, the value calculated by using pseudopotentials in which the 4f orbital participates in the chemical bonding (Dolg,M.; Stoll, H.; Preuss, H. THEOCHEM 1991, 231, 243] is in very good agreement with our experimental value.

Linton, Colan; Chen, Jinhai; Steimle, Timothy C.

2009-04-01

69

Order of Magnitude Smaller Limit on the Electric Dipole

potentially measurable electron electric dipole moment (EDM), de, in the range of 10-27 to 10-30 eÂ·cm. The EDM and molecules can be used to precisely probe for the electron electric dipole moment (EDM), de, via the energy#12;Order of Magnitude Smaller Limit on the Electric Dipole Moment of the Electron The ACME

Gabrielse, Gerald

70

Mathematical modelling of the implant-assisted magnetic drug targeting system of Avilés, Ebner and Ritter is performed. In order to model the agglomeration of particles known to occur in this system, the magnetic dipoledipole and hydrodynamic interactions are included. Such interactions were calculated previously by Mikkelsen et al. under low magnetic fields (~0.05T) in microfluidic systems. Here, a higher magnetic field

P. J. Cregg; Kieran Murphy; Adil Mardinoglu

2009-01-01

71

Electric Dipole Moments of Neutron-Odd Nuclei

The electric dipole moments (EDMs) of neutron-odd nuclei with even protons are systematically evaluated. We first derive the relation between the EDM and the magnetic moment operators by making use of the core polarization scheme. This relation enables us to calculate the EDM of neutron-odd nuclei without any free parameters. From this calculation, one may find the best atomic system suitable for future EDM experiments.

Takehisa Fujita; Sachiko Oshima

2011-02-15

72

New limit on the electron electric dipole moment

We present the result of our most recent search for T-violation in 205Tl, which is interpreted in terms of an electric dipole moment of the electron de. We find de = (6.9 plus/minus 7.4) times 10{sup -28} e cm. The present apparatus is a major upgrade of the atomic beam magnetic resonance device used to set the previous limit on de.

Regan, B.C.; Commins, Eugene D.; Schmidt, Christian J.; DeMille, David

2001-08-08

73

The Electric Dipole Moment of the Nucleons in Holographic QCD

We introduce the strong CP-violation in the framework of AdS/QCD model and calculate the electric dipole moments of nucleons as well as the CP-violating pion-nucleon coupling. Our holographic estimate of the electric dipole moments gives for the neutron d_n=1.08 X 10^{-16} theta (e cm), which is comparable with previous estimates. We also predict that the electric dipole moment of the proton should be precisely the minus of the neutron electric dipole moment, thus leading to a new sum rule on the electric dipole moments of baryons.

Deog Ki Hong; Hyun-Chul Kim; Sanjay Siwach; Ho-Ung Yee

2007-10-31

74

Dark forces and atomic electric dipole moments

Postulating the existence of a fnite-mass mediator of T,P-odd coupling between atomic electrons and nucleons we consider its effect on permanent electric dipole moment (EDM) of diamagnetic atoms. We present both numerical and analytical analysis for such mediator-induced EDMs and compare it with EDM results for the conventional contact interaction. Based on this analysis we derive limits on coupling strengths and carrier masses from experimental limits on EDM of 199Hg atom.

Heman Gharibnejad; Andrei Derevianko

2015-01-17

75

Search for the electron electric dipole moment

In most viable extensions to the Standard Model, the electron is predicted to have a time-reversal violating electric dipole moment (EDM) at, or within a few orders of magnitude of, the current experimental upper bound. Experimental searches for the electron EDM hence have the capability to probe CP-violation at TeV (and potentially much higher) energy scales. Our group is developing

David Demille; S. Bickman; Y. Jiang; V. Prasad; D. Kawall; R. Paolino

2008-01-01

76

The electric dipole moment of the electron

Recent experimental progress in the search for atomic electric dipole moments (EDMs) dA of cesium and thallium leads in particular to a substantially increased sensitivity to a possible electron EDM de compared with existing upper bounds. Further considerable improvement in the measurement of dTl is likely. After a brief synopsis of the theory of atomic EDMs, the authors discuss-in view

Werner Bernreuther; Mahiko Suzuki

1991-01-01

77

Dark forces and atomic electric dipole moments

NASA Astrophysics Data System (ADS)

Postulating the existence of a finite-mass mediator of T,P-odd coupling between atomic electrons and nucleons, we consider its effect on the permanent electric dipole moment (EDM) of diamagnetic atoms. We present both numerical and analytical analysis for such mediator-induced EDMs and compare it with EDM results for the conventional contact interaction. Based on this analysis, we derive limits on coupling strengths and carrier masses from experimental limits on EDM of the 199Hg atom.

Gharibnejad, Heman; Derevianko, Andrei

2015-02-01

78

General classical equation of spin motion is explicitly derived for a particle with magnetic and electric dipole moments in electromagnetic fields. Equation describing the spin motion relatively the momentum direction in storage rings is also obtained.

Takeshi Fukuyama; Alexander J. Silenko

2013-11-09

79

Incipient magnetic rotation? A magnetic dipole band in 104Cd

High spin states of the nucleus 104Cd have been studied using the Gammapshere array. The level scheme for 104Cd has been revised and evidence for a structure consisting of magnetic dipole transitions is presented. Shell model calculations, published previously, are invoked to support an interpretation of this structure as an incpient case of magnetic rotation where the transversal magnetic dipole moment is not strong enough to break the signature symmetry.

D. G. Jenkins; R. Wadsworth; J. A. Cameron; M. P. Carpenter; C. J. Chiara; R. M. Clark M. Devlin; P. Fallon; D. B. Fossan; I. M. Hibbert; R. V. F. Janssens; V. P. Janzen; R. Kruecken; D. R. LaFosse; G. J. Lane; T. Lauritsen; I. Y. Lee; A. O. Macchiavelli; C. M. Parry; D. G. Sarsantities; J. M. Sears; D. Seweryniak; J. F. Smith; K. Starosta; D. Ward; I. Wiedenhoever; A. N. Wilson; J. N. Wilson; S. Frauendorf

2000-07-05

80

Circular current loops, magnetic dipoles and spherical harmonic analysis.

Spherical harmonic analysis (SHA) is the most used method of describing the Earth's magnetic field, even though spherical harmonic coefficients (SHC) almost completely defy interpretation in terms of real sources. Some moderately successful efforts have been made to represent the field in terms of dipoles placed in the core in an effort to have the model come closer to representing real sources. Dipole sources are only a first approximation to the real sources which are thought to be a very complicated network of electrical currents in the core of the Earth. -Author

Alldredge, L.R.

1980-01-01

81

Searching for an accurate optical clock which can serve as a better time standard than the present-day atomic clock is highly demanding from several areas of science and technology. Several attempts have been made to build more accurate clocks with different ion species. In this paper, we discuss the electric quadrupole and hyperfine shifts in the 5d{sup 9}6s{sup 2} {sup 2}D{sub 5/2}(F=0,m{sub F}=0){r_reversible}5d{sup 10}6s {sup 2}S{sub 1/2}(F=2,m{sub F}=0) clock transition in {sup 199}Hg{sup +}, one of the most promising candidates for next-generation optical clocks. We have applied Fock-space unitary coupled-cluster theory to study the electric quadrupole moment of the 5d{sup 9}6s{sup 2} {sup 2}D{sub 5/2} state and magnetic dipole hyperfine constants of 5d{sup 9}6s{sup 2} {sup 2}D{sub 3/2,5/2} and 5d{sup 10}6s{sup 1} {sup 2}S{sub 1/2} states, respectively, of {sup 199}Hg{sup +}. We have also compared our results with available data. To the best of our knowledge, this is the first time a variant of coupled-cluster theories has been applied to study these kinds of properties of Hg{sup +} and is the most accurate estimate of these quantities to date.

Sur, Chiranjib; Chaudhuri, Rajat K. [Department of Astronomy, Ohio State University, Columbus, Ohio 43210 (United States); Indian Institute of Astrophysics, Koramangala, Block II, Bangalore 560 034 (India)

2007-09-15

82

Near-Field Magnetic Dipole Moment Analysis

NASA Technical Reports Server (NTRS)

This paper describes the data analysis technique used for magnetic testing at the NASA Goddard Space Flight Center (GSFC). Excellent results have been obtained using this technique to convert a spacecraft s measured magnetic field data into its respective magnetic dipole moment model. The model is most accurate with the earth s geomagnetic field cancelled in a spherical region bounded by the measurement magnetometers with a minimum radius large enough to enclose the magnetic source. Considerably enhanced spacecraft magnetic testing is offered by using this technique in conjunction with a computer-controlled magnetic field measurement system. Such a system, with real-time magnetic field display capabilities, has been incorporated into other existing magnetic measurement facilities and is also used at remote locations where transport to a magnetics test facility is impractical.

Harris, Patrick K.

2003-01-01

83

Magnetic dipole strength in 128Xe and 134Xe in the spin-flip resonance region

NASA Astrophysics Data System (ADS)

The magnetic dipole strength in the energy region of the spin-flip resonance is investigated in 128Xe and 134Xe using quasimonoenergetic and linearly polarized ? -ray beams at the High-Intensity ? -Ray Source facility in Durham, North Carolina, USA. Absorption cross sections were deduced for the magnetic and electric and dipole strength distributions separately for various intervals of excitation energy, including the strength of states in the unresolved quasicontinuum. The magnetic dipole strength distributions show structures resembling a resonance in the spin-flip region around an excitation energy of 8 MeV. The electric dipole strength distributions obtained from the present experiments are in agreement with the ones deduced from an earlier experiment using broad-band bremsstrahlung instead of a quasimonoenergetic beam. The experimental magnetic and electric dipole strength distributions are compared with phenomenological approximations and with predictions of a quasiparticle random phase approximation in a deformed basis.

Massarczyk, R.; Rusev, G.; Schwengner, R.; Dönau, F.; Bhatia, C.; Gooden, M. Â. E.; Kelley, J. Â. H.; Tonchev, A. Â. P.; Tornow, W.

2014-11-01

84

The Case of the Disappearing Magnetic Dipole

ERIC Educational Resources Information Center

The problem of an oscillating magnetic dipole at the centre of a lossless dielectric spherical shell is considered. For simplicity, the free-space wavelength is taken to be much greater than the shell radii, but the relative permittivity [epsilon][subscript r] of the shell is taken as much greater than unity, so the wavelength in the shell could

Gough, W.

2008-01-01

85

Microscopic magnetic dipole radiation in neutron stars

There is ${}^3P_2$ neutron superfluid region in NS (neutron star) interior. For a rotating NS, the ${}^3P_2$ superfluid region is like a system of rotating magnetic dipoles. It will give out electromagnetic radiation, which may provides a new heating mechanism of NSs. This heating mechanism plus some cooling agent may give sound explanation to NS glitches.

Hao Tong; Qiu-he Peng; Hua Bai

2008-01-03

86

We have shown that the study of dipole moments, both magnetic and electric, in storage rings offer unique opportunities in probing physics beyond the Standard Model (SM). Both methods use similar techniques (particle and spin precession in magnetic storage rings). We are currently investigating the systematic errors associated with the resonance electric dipole moment (EDM) method. So far it looks very promising.

SEMERTZIDIS, Y.K.

2005-05-23

87

Stability of superconducting ISABELLE dipole magnets

The concept of the minimum propagating zone (MPZ) is used to examine the causes of quenches in ISABELLE cosine theta superconducting dipole magnets. The size of disturbances large enough to exceed the MPZ and initiate quenches is estimated and compared with the size of disturbances which may be produced in the magnets. A suggestion for reducing the size of these disturbances through individual support of the coil block is outlined.

Wipf, S.L.

1981-04-01

88

Experimental search for the electron Electric Dipole Moment using solid state techniques

We report results of an experimental search for the permanent Electric Dipole Moment (EDM) of the electron using a solid state system. The experiment uses a paramagnetic insulator (gadolinium gallium garnet) with a large magnetic response at low temperatures. The presence of the electron EDM leads to a finite magnetization when the garnet sample is subjected to a strong electric

Y. J. Kim; C.-Y. Liu; S. K. Lamoreaux; G. Reddy

2011-01-01

89

NASA Astrophysics Data System (ADS)

A procedure for calculating electric dipole transition moments and permanent dipole moments from spin-orbit configuration interaction (SOCI) wave functions has been developed in the context of the COLUMBUS ab initio electronic structure programs. The SOCI procedure requires relativistic effective core potentials and their corresponding spin-orbit coupling operators to define the molecular Hamiltonian, electric dipole transition moment and permanent dipole moment matrices. The procedure can be used for any molecular system for which the COLUMBUS SOCI circuits are applicable. Example applications are reported for transition moments and dipole moments for a series of electronic states of LiBe and LiSr defined in diatomic relativistic ??-coupling.

Roostaei, B.; Ermler, W. C.

2012-03-01

90

Neutron Electric Dipole Moment at Fixed Topology

We describe the finite volume effects of CP-odd quantities, such as the neutron electric dipole moment and the anapole moment in the $\\theta$-vacuum, under different topological sectors. We evaluate the three-point Green's functions for the electromagnetic current in a fixed non-trivial topological sector in order to extract these CP-odd observables. We discuss the role of zero modes in the CP-odd Green's function and show that, in the quenched approximation, there is a power divergence in the quark mass for CP-odd quantities at finite volume.

Keh-Fei Liu

2009-07-03

91

Electric Dipole Moment Enhancement Factor of Thallium

NASA Astrophysics Data System (ADS)

The goal of this work is to resolve the present controversy in the value of the electric dipole moment (EDM) enhancement factor of Tl. We carry out several calculations by different high-precision methods, study previously omitted corrections, as well as test our methodology on other, parity conserving, quantities. We find the EDM enhancement factor of Tl to be equal to -573(20). This value is 20% larger than the recently published result of Nataraj et al. [Phys. Rev. Lett. 106, 200403 (2011)PRLTAO0031-900710.1103/PhysRevLett.106.200403], but agrees very well with several earlier results.

Porsev, S. G.; Safronova, M. S.; Kozlov, M. G.

2012-04-01

92

Electric dipole moments (EDM) of ionic atoms

Recent investigations show that the second-order perturbation calculations of electric dipole moments (EDM) from the finite nuclear size as well as the relativistic effects are all canceled out by the third-order perturbation effects and that this is due to electron screening. To derive the nucleon EDM from the nucleus, we propose to measure the EDM of an ionic system. In this case, it is shown that the nucleon EDM can survive by the reduction factor of 1/Z for the ionic system with one electron stripped off.

Oshima, Sachiko [Department of Physics, Faculty of Science and Technology, Nihon University, Tokyo (Japan)

2010-03-15

93

Electric Dipole Moments in Split Supersymmetry

We perform a quantitative study of the neutron and electron electric dipole moments (EDM) in Supersymmetry, in the limit of heavy scalars. The leading contributions arise at two loops. We give the complete analytic result, including a new contribution associated with Z-Higgs exchange, which plays an important and often leading role in the neutron EDM. The predictions for the EDM are typically within the sensitivities of the next generation experiments. We also analyse the correlation between the electron and neutron EDM, which provides a robust test of Split Supersymmetry.

G. F. Giudice; A. Romanino

2005-10-14

94

Electron electric-dipole-moment experiment using electric-field quantized slow cesium atoms

A proof-of-principle electron electric-dipole-moment (e-EDM) experiment using slow cesium atoms, nulled magnetic fields, and electric-field quantization has been performed. With the ambient magnetic fields seen by the atoms reduced to less than 200 pT, an electric field of 6 MV/m lifts the degeneracy between states of unequal |m{sub F}| and, along with the low ({approx_equal}3 m/s) velocity, suppresses the systematic effect from the motional magnetic field. The low velocity and small residual magnetic field have made it possible to induce transitions between states and to perform state preparation, analysis, and detection in regions free of applied static magnetic and electric fields. This experiment demonstrates techniques that may be used to improve the e-EDM limit by two orders of magnitude, but it is not in itself a sensitive e-EDM search, mostly due to limitations of the laser system.

Amini, Jason M.; Munger, Charles T. Jr.; Gould, Harvey [Mail Stop 71-259, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

2007-06-15

95

Development of a simulation for measuring neutron electric dipole moment

NASA Astrophysics Data System (ADS)

The neutron electric dipole moment (nEDM) is sensitive to new physics beyond the standard model and could prove to be a new source of CP violation. Several experiments are being planned worldwide for its high-precision measurement. The nEDM is measured as the ultracold neutron (UCN) spin precession in a storage bottle under homogeneous electric and magnetic fields. In nEDM measurement, the systematic uncertainties are due to the motion of the UCNs, the geometry of the measurement system, and inhomogeneous electric and magnetic fields. Therefore, it is essential to quantitatively understand these effects in order to reduce them. Geant4UCN is an ideal simulation framework because it can compute the UCN trajectory, evaluate the time evolution of the spin precession due to arbitrary electric and magnetic fields, and define the storage geometry flexibly. We checked how accurately Geant4UCN can calculate the spin precession. We found that because of rounding errors, it cannot simulate it accurately enough for nEDM experiments, assuming homogeneous electric and magnetic fields with strengths of 10 kV/cm and 1 ?T, respectively, and 100 s of storage. In this paper, we report on its discrepancies and describe a solution.

Katayama, Ryo; Mishima, Kenji; Yamashita, Satoru; Sakurai, Dai; Kitaguchi, Masaaki; Yoshioka, Tamaki; Seki, Yoshichika

2014-07-01

96

Instantaneous power radiated from magnetic dipole moments

NASA Astrophysics Data System (ADS)

We compute the power radiated per unit solid angle of a moving magnetic dipole moment, and its instantaneous radiated power, both non-relativistically and relativistically. This is then applied to various interesting situations: solar neutrons, electron synchrotrons and cosmological Dirac neutrinos. Concerning the latter, we show that hypothesized early-universe Big Bang conditions allow for neutrino radiation cooling and provide an energy loss-mechanism for subsequent neutrino condensation.

Morley, P. D.; Buettner, D. J.

2015-03-01

97

Instantaneous Power Radiated from Magnetic Dipole Moments

We compute the power radiated per unit solid angle of a moving magnetic dipole moment, and its instantaneous radiated power, both non-relativistically and relativistically. This is then applied to various interesting situations: solar neutrons, electron synchrotrons and cosmological Dirac neutrinos. Concerning the latter, we show that hypothesized early-universe Big Bang conditions allow for neutrino radiation cooling and provide an energy loss-mechanism for subsequent neutrino condensation.

Peter D. Morley; Douglas J. Buettner

2014-07-04

98

Generalized dyons and magnetic dipoles: The issue of angular momentum

NASA Astrophysics Data System (ADS)

It is known that a non-Abelian magnetic monopole cannot rotate globally (although it may possess a nonzero angular momentum density). At the same time, the total angular momentum of a magnetic dipole equals the electric charge. In this work we question the generality of these results by considering a number of generalizations of the Georgi-Glashow model. We study two different types of finite energy, regular configurations: solutions with net magnetic charge and monopole-antimonopole pairs with zero net magnetic charge. These configurations are endowed with an electric charge and carry also a nonvanishing angular momentum density. However, we argue that the qualitative results found in the Georgi-Glashow model are generic and thus a magnetic monopole cannot spin as long as the matter fields feature the usual "monopole" asymptotic behavior independently of the dynamics of the model. A study of the properties of the dyons and magnetic dipoles in some generalizations of the Georgi-Glashow model supplemented with higher order Skyrme-like terms in the gauge curvature and Higgs fields is given quantitatively.

Navarro-Lérida, Francisco; Radu, Eugen; Tchrakian, D. H.

2014-09-01

99

Electron electric dipole moment experiment using electric-fieldquantized slow cesium atoms

A proof-of-principle electron electric dipole moment (e-EDM)experiment using slow cesium atoms, nulled magnetic fields, and electricfield quantization has been performed. With the ambient magnetic fieldsseen by the atoms reduced to less than 200 pT, an electric field of 6MV/m lifts the degeneracy between states of unequal lbar mF rbar and,along with the low (approximately 3 m/s) velocity, suppresses thesystematic effect from the motional magnetic field. The low velocity andsmall residual magnetic field have made it possible to induce transitionsbetween states and to perform state preparation, analysis, and detectionin regions free of applied static magnetic and electric fields. Thisexperiment demonstrates techniques that may be used to improve the e-EDMlimit by two orders of magnitude, but it is not in itself a sensitivee-EDM search, mostly due to limitations of the laser system.

Amini, Jason M.; Munger Jr., Charles T.; Gould, Harvey.

2007-04-05

100

Dipole-sheet multipole magnets for accelerators

The dipole-sheet formalism can be used to describe both cylindrical current-sheet multipole magnets and cylindrical-bore magnets made up of permanent magnet blocks. For current sheets, the formalism provides a natural way of finding a finite set of turns that approximate a continuous distribution. The formalism is especially useful in accelerator applications where large-bore, short, high-field-quality magnets that are dominated by fringe fields are needed. A further advantage of the approach is that in system switch either open or cylindrically symmetric magnetic boundaries, analytical expressions for the three-dimensional fields that are suitable for rapid numerical evaluation can be derived. This development is described in some detail. Also, recent development in higher-order particle-beam optics codes based on the formalism are described briefly.

Walstrom, P.L. (Los Alamos National Lab., NM (United States). Grumman Space and Electronics Systems)

1994-07-01

101

A search for the electric dipole of the electron

We report a new upper limit on the electric dipole moment (EDM) of the electron of d{sub e} = 0.1 {plus minus} 3.2 {times} 10{sup {minus}26} e-cm. This precision is one hundred times better than any previously published limit and a factor of two better than that of unofficial reports. Recently there has been a great deal of theoretical interest in the possibility of a non-zero electron EDM. Models such as the left-right-symmetric Standard Model and an off-standard'' model with new heavy neutrinos are constrained by the new limit on d{sub e}. A non-zero electron EDM would violate the time reversal and parity space-time symmetries. T-violation was observed in neutral kaon decay and is still not fully explained by the Standard Model. Our experimental technique involves searching for an energy shift, linear in applied electric field, between the m{sub F} = 1 and m{sub F} = {minus}1 magnetic sublevels of the F=1 hyperfine level of the 6{sup 2}P{sub 1/2} ground state of atomic thallium. If the electron has a non-zero EDM, this thallium state will exhibit an atomic electric dipole moment that is roughly 600 times larger. The energy shift is detected with the technique of magnetic resonance spectroscopy, employing separated oscillating fields, applied to an atomic beam of thallium. In the approach, any relative phase-shift between the m{sub F} = {plus minus}1 components of the F=1 wavefunction acquired by the atom as it travels through an electric field is detected through interference with two separate oscillating magnetic fields located on either side of the electric field. The new level of precision is achieved through several improvements on previous experiments including employment of a vertical apparatus, two opposing atomic beams, and optical pumping for atomic state selection and analysis.

Abdullah, K.F.

1989-08-01

102

PULSAR PAIR CASCADES IN A DISTORTED MAGNETIC DIPOLE FIELD

We investigate the effect of a distorted neutron star dipole magnetic field on pulsar pair cascade multiplicity and pair death lines. Using a simple model for a distorted dipole field that produces an offset polar cap (PC), we derive the accelerating electric field above the PC in space-charge-limited flow. We find that even a modest azimuthally asymmetric distortion can significantly increase the accelerating electric field on one side of the PC and, combined with a smaller field line radius of curvature, leads to larger pair multiplicity. The death line for producing pairs by curvature radiation moves downward in the P- P-dot diagram, allowing high pair multiplicities in a larger percentage of the radio pulsar population. These results could have important implications for the radio pulsar population, high energy pulsed emission, and the pulsar contribution to cosmic ray positrons.

Harding, Alice K.; Muslimov, Alex G. [Astrophysics Science Division, NASA/Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2011-01-01

103

Pulsar Pair Cascades in a Distorted Magnetic Dipole Field

NASA Technical Reports Server (NTRS)

We investigate the effect of a distorted neutron star dipole magnetic field on pulsar pair cascade multiplicity and pair death lines. Using a simple model for a distorted dipole field that produces an offset polar cap (PC), we derive the accelerating electric field above the PC in space-charge-limited flow. We find that even a modest azimuthally asymmetric distortion can significantly increase the accelerating electric field on one side of the PC and, combined with a smaller field line radius of curvature, leads to larger pair multiplicity. The death line for producing pairs by curvature radiation moves downward in the P-P-dot diagram, allowing high pair multiplicities in a larger percentage of the radio pulsar population. These results could have important implications for the radio pulsar population, high energy pulsed emission, and the pulsar contribution to cosmic ray positrons.

Harding, Alice K.; Muslimov, Alex G.

2010-01-01

104

Electric dipole moments: A global analysis

NASA Astrophysics Data System (ADS)

We perform a global analysis of searches for the permanent electric dipole moments (EDMs) of the neutron, neutral atoms, and molecules in terms of six leptonic, semileptonic, and nonleptonic interactions involving photons, electrons, pions, and nucleons. By translating the results into fundamental charge-conjugation-parity symmetry (CP) violating effective interactions through dimension six involving standard model particles, we obtain rough lower bounds on the scale of beyond the standard model CP-violating interactions ranging from 1.5 TeV for the electron EDM to 1300 TeV for the nuclear spin-independent electron-quark interaction. We show that planned future measurements involving systems or combinations of systems with complementary sensitivities to the low-energy parameters may extend the mass reach by an order of magnitude or more.

Chupp, Timothy; Ramsey-Musolf, Michael

2015-03-01

105

Electric Dipole Moments: A Global Analysis

We perform a global analysis of searches for the permanent electric dipole moments (EDMs) of the neutron, neutral atoms, and molecules in terms of six leptonic, semileptonic, and nonleptonic interactions involving photons, electrons, pions, and nucleons. Translating the results into fundamental CP-violating effective interactions through dimension six involving Standard Model particles, we obtain rough lower bounds on the scale of beyond the Standard Model CP-violating interactions ranging from 1.5 TeV for the electron EDM to 1300 TeV for the nuclear spin-independent electron-quark interaction. We show that future measurements involving systems or combinations of systems with complementary sensitivities to the low-energy parameters may extend the mass reach by an order of magnitude or more.

Timothy Chupp; Michael Ramsey-Musolf

2014-07-03

106

Electric Dipole Radiation from Spinning Dust Grains

We discuss the rotational excitation of small interstellar grains and the resulting electric dipole radiation from spinning dust. Attention is given to excitation and damping of rotation by: collisions with neutrals; collisions with ions; plasma drag; emission of infrared radiation; emission of microwave radiation; photoelectric emission; and formation of H_2 on the grain surface. We introduce dimensionless functions F and G which allow direct comparison of the contributions of different mechanisms to rotational drag and excitation. Emissivities are estimated for dust in different phases of the interstellar medium, including diffuse HI, warm HI, low-density photoionized gas, and cold molecular gas. Spinning dust grains can explain much, and perhaps all, of the 14-50 GHz background component recently observed in CBR studies. It should be possible to detect rotational emission from small grains by ground-based observations of molecular clouds.

B. T. Draine; A. Lazarian

1998-02-18

107

Electric Dipole Radiation from Spinning Dust Grains

We discuss the rotational excitation of small interstellar grains and the resulting electric dipole radiation from spinning dust. Attention is given to excitation and damping of rotation by: collisions with neutrals; collisions with ions; plasma drag; emission of infrared radiation; emission of microwave radiation; photoelectric emission; and formation of H_2 on the grain surface. We introduce dimensionless functions F and G which allow direct comparison of the contributions of different mechanisms to rotational drag and excitation. Emissivities are estimated for dust in different phases of the interstellar medium, including diffuse HI, warm HI, low-density photoionized gas, and cold molecular gas. Spinning dust grains can explain much, and perhaps all, of the 14-50 GHz background component recently observed in CBR studies. It should be possible to detect rotational emission from small grains by ground-based observations of molecular clouds.

Draine, B T

1998-01-01

108

Communication: Permanent dipoles contribute to electric polarization in chiral NMR spectra

Nuclear magnetic resonance spectroscopy is blind to chirality because the spectra of a molecule and its mirror image are identical unless the environment is chiral. However, precessing nuclear magnetic moments in chiral molecules in a strong magnetic field induce an electric polarization through the nuclear magnetic shielding polarizability. This effect is equal and opposite for a molecule and its mirror image but is small and has not yet been observed. It is shown that the permanent electric dipole moment of a chiral molecule is partially oriented through the antisymmetric part of the nuclear magnetic shielding tensor, causing the electric dipole to precess with the nuclear magnetic moment and producing a much larger temperature-dependent electric polarization with better prospects of detection.

Buckingham, A. David, E-mail: adb1000@cam.ac.uk [Department of Chemistry, Cambridge University, Cambridge CB2 1EW (United Kingdom)

2014-01-07

109

Electric dipole moment of the electron and of the neutron

NASA Technical Reports Server (NTRS)

It is shown that if Higgs-boson exchange mediates CP violation a significant electric dipole moment for the electron can result. Analogous effects can contribute to the neutron's electric dipole moment at a level competitive with Weinberg's three-gluon operator.

Barr, S. M.; Zee, A.

1990-01-01

110

Weak Magnetic Dipole Moments in the MSSM

We calculate the weak magnetic dipole moment of different fermions in the MSSM. In particular, we consider in detail the predictions for the WMDM of the tau lepton and bottom quark. We compare the purely SUSY contributions with two Higss doublet models and SM predictions. For the tau lepton, we show that chargino diagrams give the main SUSY contribution, which for tan beta=50 can be one order of magnitude bigger than the SM prediction. For the b quark, gluino diagrams provide the main SUSY contribution to its weak anomalous dipole moment, which is still dominated by gluon contributions. We also study how the universality assumption in the slepton sector induces correlations between the SUSY contributions to the tau WMDM and to (g-2) of the muon.

B. de Carlos; J. M. Moreno

1997-07-28

111

Prospects for 10T accelerator dipole magnets

A next-generation major accelerator will require the highest possible field to minimize the circumference; however, there have been no proven designs for suitable magnets with fields substantially higher than 5T. A number of successful 4 to 5T dipole magnets have been built in recent years; these have involved long and difficult development projects. The 3'' bore 4.25T magnets for the Doubler are being produced by the hundreds at Fermilab, and a number of prototypes of the 5.2'' bore 5T ISABELLE magnets have been built. Successful short, approx. 5T models have been made at SACLAY, KEK, and Serpukhov, and a number of model magnets with lower fields have been built at many laboratories. Field uniformity achieved in these magnets is about ..delta..B/B approx. = 10/sup -3/. 10T magnets with higher field uniformity will be a challenging development task. The general problems of high-field (10T) magnets are discussed in terms of superconductor performance and mechanical limitations.

Taylor, C.E.; Meuser, R.B.

1981-03-01

112

Neutron electric dipole moment on the lattice

We carry out a feasibility study toward a lattice QCD calculation of the neutron electric dipole moment (NEDM) in the presence of the $\\theta$ term using two different approaches. In the first method, we calculate the CP-odd electromagnetic form factor $F_3$, which becomes the NEDM in the zero momentum transfer limit. At the first order in $\\theta$, we derive a formula connecting the lattice three-point function to the CP-odd electromagnetic form factor. In the second method we directly extract the NEDM from the energy difference between spin-up and spin-down neutron states in the presence of a constant electric field, without expanding a small but non-zero $\\theta$. We test both approaches numerically, employing the domain-wall quark action with the RG improved gauge action in quenched QCD at $a^{-1}\\simeq 2$ GeV on a $16^3\\times 32\\times 16$ lattice, and further applying the second method to the clover quark action at a similar lattice spacing and nucleon mass. We obtain good signals from both approaches. In particular the second method works well with both fermion formulations.

Eigo Shintani; S. Aoki; N. Ishizuka; K. Kanaya; Y. Kikukawa; Y. Kuramashi; M. Okawa; A. Ukawa; T. Yoshié

2005-09-26

113

The ACME electron electric dipole moment search

NASA Astrophysics Data System (ADS)

Observation of a non-zero electric dipole moment (EDM) of the electron, de, within a few orders of magnitude of the current limit |de| < 1.05 x10-27 e.cm would be an indication of CP violation in physics beyond the Standard Model. Numerous extensions to the Standard Model predict a value of de in this range. The ACME Collaboration is searching for an electron EDM, by performing a precision measurement of spin precession signals from electrons in thorium monoxide (ThO) molecules. In this molecule, the EDM experiences a large electric field ( 00 GV/cm) that amplifies the spin precession. In addition, several properties of the molecular state make it possible to suppress many anticipated sources of systematic error. Our experiment uses a slow, cryogenic molecular beam to achieve unprecedented statistical accuracy. We now routinely take data with a 1? statistical uncertainty of ?de 1.0-1.5 x10-28/?T e.cm, where T is the running time in days. We will present the current status of the experiment.

Demille, David

2013-04-01

114

Electric dipole moment enhancement factor of thallium

NASA Astrophysics Data System (ADS)

A number of extensions of the standard model of particle physics predict electric dipole moments (EDM) of particles that may be observable with the present state-of-the art experiments. The EDMs arise from the violations of both parity and time-reversal invariance. The electron EDM is enhanced in certain atomic and molecular systems. One of the most stringent limits on the electron EDM de was obtained from the experiments with ^205Tl: de<1.6 10-27e cm [Regan et al., PRL 88, 071805 (2002)]. This result crucially depend on the calculated value of the effective electric field on the valence electron. In the case of Tl this effective field is proportional to the applied field E0, Eeff= K,0. The goal of this work is to resolve the present controversy in the value of the EDM enhancement factor K in Tl. We have carried out several calculations by different high-precision methods, studied previously omitted corrections, as well as tested our methodology on other parity conserving quantities. We find the EDM enhancement factor of Tl to be equal to -573(20). This value is 20% larger than the recently published result of Nataraj et al. [PRL 106, 200403 (2011)] but agrees very well with several earlier results.

Porsev, Sergey; Safronova, Marianna; Kozlov, Mikhail

2012-06-01

115

NSDL National Science Digital Library

In this two-part activity, students learn about electromagnetism by constructing electromagnets and observing their behavior. They will discover that there is a close relationship between electricity and magnetism in that moving magnets can induce electric currents and that electric currents can cause magnetism. They also learn that electric current flowing in a wire creates a magnetic field around it.

116

Space propulsion by fusion in a magnetic dipole

The unique advantages of fusion rocket propulsion systems for distant missions are explored using the magnetic dipole configurations as an example. The dipole is found to have features well suited to space applications. Parameters are presented for a system producing a specific power of kW/kg, capable of interplanetary flights to Mars in 90 days and to Jupiter in a year, and of extra-solar-system flights to 1000 astronomical units (the Tau mission) in 20 years. This is about 10 times better specific power performance than nuclear electric fission systems. Possibilities to further increase the specific power toward 10 kW/kg are discussed, as is an approach to implementing the concept through proof-testing on the moon. 20 refs., 14 figs., 2 tabs.

Teller, E.; Glass, A.J.; Fowler, T.K. (Lawrence Livermore National Lab., CA (United States)); Hasegawa, A. (AT and T Bell Labs., Murray Hill, NJ (United States)); Santarius, J.F. (Wisconsin Univ., Madison, WI (United States). Fusion Technology Inst.)

1991-07-15

117

The electric dipole moment of cobalt monoxide, CoO

A number of low-rotational lines of the E{sup 4}?{sub 7/2}???X{sup 4}?{sub 7/2} (1,0) band system of cobalt monoxide, CoO, were recorded field free and in the presence of a static electric field. The magnetic hyperfine parameter, h{sub 7/2}, and the electron quadrupole parameter, eQq{sub 0}, for the E{sup 4}?{sub 7/2}(? = 1) state were optimized from the analysis of the field-free spectrum. The permanent electric dipole moment, ?{sup -vector}{sub el}, for the X{sup 4}?{sub 7/2} (? = 0) and E{sup 4}?{sub 7/2} (? = 1) states were determined to be 4.18 ħ 0.05 D and 3.28 ħ 0.05 D, respectively, from the analysis of the observed Stark spectra of F? = 7???F? = 6 branch feature in the Q(7/2) line and the F? = 8???F? = 7 branch feature in the R(7/2) line. The measured dipole moments of CoO are compared to those from theoretical predictions and the trend across the 3d-metal monoxide series discussed.

Zhuang, Xiujuan, E-mail: zhuangxj@hnu.edu.cn [College of Physics and Microelectronics Science, Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China)] [College of Physics and Microelectronics Science, Key Laboratory for Micro-Nano Physics and Technology of Hunan Province, Hunan University, Changsha 410082 (China); Steimle, Timothy C. [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States)] [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States)

2014-03-28

118

Electric dipole polarizability and the neutron skin

NASA Astrophysics Data System (ADS)

The recent high-resolution measurement of the electric dipole (E1) polarizability ?D in 208Pb [A. Tamii , Phys. Rev. Lett.PRLTAO0031-900710.1103/PhysRevLett.107.062502 107, 062502 (2011)] provides a unique constraint on the neutron-skin thickness of this nucleus. The neutron-skin thickness rskin of 208Pb is a quantity of critical importance for our understanding of a variety of nuclear and astrophysical phenomena. To assess the model dependence of the correlation between ?D and rskin, we carry out systematic calculations for 208Pb, 132Sn, and 48Ca based on the nuclear density functional theory using both nonrelativistic and relativistic energy density functionals. Our analysis indicates that whereas individual models exhibit a linear dependence between ?D and rskin, this correlation is not universal when one combines predictions from a host of different models. By averaging over these model predictions, we provide estimates with associated systematic errors for rskin and ?D for the nuclei under consideration. We conclude that precise measurements of rskin in both 48Ca and 208Pbcombined with the recent measurement of ?Dshould significantly constrain the isovector sector of the nuclear energy density functional.

Piekarewicz, J.; Agrawal, B. K.; Colò, G.; Nazarewicz, W.; Paar, N.; Reinhard, P.-G.; Roca-Maza, X.; Vretenar, D.

2012-04-01

119

Electric dipole polarizability and the neutron skin

The recent high-resolution measurement of the electric dipole (E1) polarizability (alphad) in 208Pb [Phys. Rev. Lett. 107, 062502 (2011)] provides a unique constraint on the neutron-skin thickness of this nucleus. The neutron-skin thickness (rskin) of 208Pb is a quantity of critical importance for our understanding of a variety of nuclear and astrophysical phenomena. To assess the model dependence of the correlation between alphad and rskin, we carry out systematic calculations for 208Pb, 132Sn, and 48Ca based on the nuclear density functional theory (DFT) using both non-relativistic and relativistic energy density functionals (EDFs). Our analysis indicates that whereas individual models exhibit a linear dependence between alphad and rskin, this correlation is not universal when one combines predictions from a host of different models. By averaging over these model predictions, we provide estimates with associated systematic errors for rskin and alphad for the nuclei under consideration. We conclude that precise measurements of rskin in both 48Ca and 208Pb---combined with the recent measurement of alphad---should significantly constrain the isovector sector of the nuclear energy density functional.

J. Piekarewicz; B. K. Agrawal; G. Colo; W. Nazarewicz; N. Paar; P. -G. Reinhard; X. Roca-Maza; D. Vretenar

2012-01-18

120

Electric dipole polarizability and the neutral skin

The recent high-resolution measurement of the electric dipole (E1) polarizability {alpha}{sub D} in {sup 208}Pb [A. Tamii et al. Phys. Rev. Lett. 107 062502 (2011)] provides a unique constraint on the neutron-skin thickness of this nucleus. The neutron-skin thickness r{sub skin} of {sup 208}Pb is a quantity of critical importance for our understanding of a variety of nuclear and astrophysical phenomena. To assess the model dependence of the correlation between {alpha}{sub D} and r{sub skin}, we carry out systematic calculations for {sup 208}Pb, {sup 132}Sn, and {sup 48}Ca based on the nuclear density functional theory using both nonrelativistic and relativistic energy density functionals. Our analysis indicates that whereas individual models exhibit a linear dependence between {alpha}{sub D} and r{sub skin}, this correlation is not universal when one combines predictions from a host of different models. By averaging over these model predictions, we provide estimates with associated systematic errors for r{sub skin} and {alpha}{sub D} for the nuclei under consideration. We conclude that precise measurements of r{sub skin} in both {sup 48}Ca and {sup 208}Pb - combined with the recent measurement of {alpha}{sub D} - should significantly constrain the isovector sector of the nuclear energy density functional.

Piechaczek, A. [Louisiana State University; Nazarewicz, Witold [ORNL; Reinhard, P.-G. [Universitat Erlangen, Germany; Agrawal, Bijay K [ORNL; Colo, Gianluca [ORNL; Paar, Nils [ORNL; Roca-Maza, X [IFGA, University of Milan and INFN, Milano, Italy; Vretenar, Dario [ORNL

2012-01-01

121

Nuclear Electric Dipole Moment of 3He

A permanent electric dipole moment (EDM) of a physical system would require time-reversal (T) violation, which is equivalent to charge-conjugation-parity (CP) violation by CPT invariance. Experimental programs are currently pushing the limits on EDMs in atoms, nuclei, and the neutron to regimes of fundamental theoretical interest. Nuclear EDMs can be studied at ion storage rings with sensitivities that may be competitive with atomic and neutron measurements. Here we calculate the magnitude of the CP-violating EDM of {sup 3}He and the expected sensitivity of such a measurement to the underlying CP-violating interactions. Assuming that the coupling constants are of comparable magnitude for {pi}-, {rho}-, and {omega}-exchanges, we find that the pion-exchange contribution dominates. Finally, our results suggest that a measurement of the {sup 3}He EDM is complementary to the planned neutron and deuteron experiments, and could provide a powerful constraint for the theoretical models of the pion-nucleon P,T-violating interaction.

Stetcu, I; P.Liu, C; Friar, J L; Hayes, A C; Navratil, P

2008-04-08

122

The search for permanent electric dipole moments

Permanent electric dipole moments (EDMs) of fundamental systems with spin - particles, nuclei, atoms or molecules violate parity and time reversal invariance. Invoking the CPT theorem, time reversal violation implies CP violation. Although CP-violation is implemented in the standard electro-weak theory, EDM generated this way remain undetectably small. However, this CP-violation also appears to fail explaining the observed baryon asymmetry of our universe. Extensions of the standard theory usually include new sources of CP violation and often predict sizeable EDMs. EDM searches in different systems are complementary and various efforts worldwide are underway and no finite value has been established yet. The prototype of an EDM search is the pursuit of the EDM of the neutron. It has the longest history and at the same time is at the forefront of present research. The talk aims at giving an overview of the field with emphasis on our efforts within an international collaboration at PSI, nedm.web.psi.ch.

Kirch, Klaus [PSI-Villigen - ETH Zürich

2013-02-13

123

Confronting Higgcision with Electric Dipole Moments

Current data on the signal strengths and angular spectrum of the 125.5 GeV Higgs boson still allow a CP-mixed state, namely, the pseudoscalar coupling to the top quark can be as sizable as the scalar coupling: $C_u^S \\approx C_u^P =1/2$. CP violation can then arise and manifest in sizable electric dipole moments (EDMs). In the framework of two-Higgs-doublet models, we not only update the Higgs precision (Higgcision) study on the couplings with the most updated Higgs signal strength data, but also compute all the Higgs-mediated contributions from the 125.5 GeV Higgs boson to the EDMs, and confront the allowed parameter space against the existing constraints from the EDM measurements of Thallium, neutron, Mercury, and Thorium monoxide. We found that the combined EDM constraints restrict the pseudoscalar coupling to be less than about $10^{-2}$, unless there are contributions from other Higgs bosons, supersymmetric particles, or other exotic particles that delicately cancel the current Higgs-mediated contributions.

Kingman Cheung; Jae Sik Lee; Eibun Senaha; Po-Yan Tseng

2014-06-24

124

Magnetostatic potential theory and the lunar magnetic dipole field

NASA Technical Reports Server (NTRS)

The lunar magnetic dipole moment is discussed. It is proposed that if a primordial core magnetic field existed, it would give rise to a present day nonzero external dipole magnetic field. This conclusion is based on the assumption that the lunar mantle is at least slightly ferromagnetic, and thus would maintain a permanent magnetization after the disappearance of the core magnetic field. Using a simple mathematical model of the moon, calculations are performed which support this hypothesis.

Goldstein, M. L.

1975-01-01

125

Possible Constraints on Neutron Electric Dipole Moment from Pulsar Radiation

Even if only a small fraction of neutron dipole moments are aligned in a neutron star, observed pulsar radiation loses provide a stringent limit on the neutron electric dipole moment of <10-29 ecm, more stringent than best current experimental limits.

C. Sivaram

2010-02-12

126

Electric dipole moments of Escherichia coli HB 101

The theoretical and experimental studies of the particles' electric dipole moments in the microscopic and submicroscopic size range show that in the case of polar and conductive media the interfacial components of the dipole moments are of greatest importance. While in the range of manometer's sizes there seems to be no important problems in the identification and in the estimation

Stoyl P. Stoylov; Anna Y. Gyurova; Viktor Bunin; Alexander Angersbach; Ralitsa N. Georgieva; Svetla T. Danova

2009-01-01

127

EDM@SNS collaboration The discovery of a neutron EDM (Electric Dipole Moment) above the Standard Model background, which in the atom it can be used as a sensitive magnetic field monitor. High densities of trapped ultra

128

Limit on the Electron Electric Dipole Moment in Gadolinium-Iron Garnet

A new method for the detection of the electron electric dipole moment (EDM) using a solid is described. The method involves the measurement of a voltage induced across the solid by the alignment of the sample's magnetic dipoles in an applied magnetic field, H. A first application of the method to GdIG has resulted in a limit on the electron EDM of 5x10{sup -24}e cm, which is a factor of 40 below the limit obtained from the only previous solid-state EDM experiment. The result is limited by the imperfect discrimination of an unexpectedly large voltage that is even upon the reversal of the sample magnetization.

Heidenreich, B.J.; Elliott, O.T.; Charney, N.D.; Virgien, K.A.; Bridges, A.W.; McKeon, M.A.; Peck, S.K.; Krause, D. Jr.; Gordon, J.E.; Hunter, L.R.; Lamoreaux, S.K. [Physics Department, Amherst College, Amherst, Massachusetts 01002 (United States); Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States)

2005-12-16

129

Switchable magnetic dipole induced guided vortex motion N. Verellen,1

Switchable magnetic dipole induced guided vortex motion N. Verellen,1 A. V. Silhanek,1,a W 2008; published online 16 July 2008 We present evidence of magnetically controlled vortex motion axes of the square lattice of dipoles. This guided vortex motion can be rerouted by 90° simply changing

Moshchalkov, Victor V.

130

Measurement of AC loss and magnetic field during ramps in the LHC model dipoles

We describe the systems for AC loss and magnetic field measurements developed for the LHC superconducting magnets. AC loss measurements are performed using an electric method, while field measurements are performed using either fixed pick-ups or rotating coils. We present results obtained on 1-m long model dipoles, and compare the results of the different methods in terms of average interstrand

Z. Ang; I. Bejar; L. Bottura; D. Richter; M. Sheahan; L. Walckiers; R. Wolf

1999-01-01

131

Magnetic and electric coupling effects of dielectric metamaterial

NASA Astrophysics Data System (ADS)

The coupling effects of subwavelength high-permittivity (?r > 100) arrayed ceramics which exhibit magnetic and electric Mie resonances are investigated by electromagnetic full-wave analysis. Special attention was paid to the symmetry properties of both magnetic- and electric-induced dipoles by varying independently the array periodicity. In agreement with the interactions between electric and magnetic dipoles, it is shown that resonance frequency shifts toward lower (higher) frequencies can be obtained, which depends on the longitudinal (transverse) dipole coupling strengths. Moreover, the emergence of quasi-bound states between tightly coupled basic cells is pointed out for the electric Mie resonances, which shows an unexpected frequency shift with a reverse variation.

Zhang, Fuli; Kang, Lei; Zhao, Qian; Zhou, Ji; Lippens, Didier

2012-03-01

132

Electric dipole sheets in BaTiO3/BaZrO3 superlattices

NASA Astrophysics Data System (ADS)

We investigate two-dimensional electric dipole sheets in the superlattice made of BaTiO3 and BaZrO3 using first-principles-based Monte Carlo simulations and density functional calculations. Electric dipole domains and complex patterns are observed and complex dipole structures with various symmetries (e.g., P m a 2 ,C m c m , and P m c 21 ) are further confirmed by density functional calculations, which are found to be almost degenerate in energy with the ferroelectric ground state of the A m m 2 symmetry, therefore strongly resembling magnetic sheets. More complex dipole patterns, including vortices and antivortices, are also observed, which may constitute the intermediate states that overcome the high-energy barrier of different polarization orientations previously predicted by A. I. Lebedev [Phys. Solid State 55, 1198 (2013), 10.1134/S1063783413060218]. We also show that such system possesses large electrostrictive effects that may be technologically important.

Jiang, Zhijun; Xu, Bin; Li, Fei; Wang, Dawei; Jia, C.-L.

2015-01-01

133

Analysis and design of short, iron-free dipole magnets

Iron-free, dipole magnets are used extensively as steering magnets to correct for the bending, induced by extraneous magnetic fields, of particle beams that are being transported in vacuum. Generally, the dipoles are long enough that the space occupied by the end conductors is small compared to the overall magnet length. In a recent application, however, this criteria did not apply. This has motivated a reanalysis of the characteristics of a system of small aspect ratio (length/diameter) dipoles that are spaced at relatively large axial distances.

Harvey, A.R.

1981-10-21

134

Magnetic field homogeneity perturbations in finite Halbach dipole magnets.

Halbach hollow cylinder dipole magnets of a low or relatively low aspect ratio attract considerable attention due to their applications, among others, in compact NMR and MRI systems for investigating small objects. However, a complete mathematical framework for the analysis of magnetic fields in these magnets has been developed only for their infinitely long precursors. In such a case the analysis is reduced to two-dimensions (2D). The paper details the analysis of the 3D magnetic field in the Halbach dipole cylinders of a finite length. The analysis is based on three equations in which the components of the magnetic flux density Bx, By and Bz are expanded to infinite power series of the radial coordinate r. The zeroth term in the series corresponds to a homogeneous magnetic field Bc, which is perturbed by the higher order terms due to a finite magnet length. This set of equations is supplemented with an equation for the field profile B(z) along the magnet axis, presented for the first time. It is demonstrated that the geometrical factors in the coefficients of particular powers of r, defined by intricate integrals are the coefficients of the Taylor expansion of the homogeneity profile (B(z)-Bc)/Bc. As a consequence, the components of B can be easily calculated with an arbitrary accuracy. In order to describe perturbations of the field due to segmentation, two additional equations are borrowed from the 2D theory. It is shown that the 2D approach to the perturbations generated by the segmentation can be applied to the 3D Halbach structures unless r is not too close to the inner radius of the cylinder ri. The mathematical framework presented in the paper was verified with great precision by computations of B by a highly accurate integration of the magnetostatic Coulomb law and utilized to analyze the inhomogeneity of the magnetic field in the magnet with the accuracy better than 1 ppm. PMID:24316186

Turek, Krzysztof; Liszkowski, Piotr

2014-01-01

135

NASA Astrophysics Data System (ADS)

Electric quadrupole interactions at 181Ta impurity in the intermetallic compound Zr2Ni7 have been studied by perturbed angular correlation technique. It has been found that there are two electric field gradients (EFG) at the 181Ta site due to two different crystalline configurations in Zr2Ni7, while contradictory results were reported from previous investigations. The values of EFG at room temperature have been found to be Vzz=7.9×1017 V/cm2 and 7.1×1017 V/cm2 corresponding to present experimental values of quadrupole frequencies and asymmetry parameters for the two sites: ?Q1=70.7(1) Mrad/s, ?=0.28(1), ?=0.8(2)% (site fraction 84%) and ?Q2=63(1) Mrad/s, ?=0.35(5), ??0 (site fraction 9%). Electric field gradients and asymmetry parameters have been computed from the complementary first-principles density functional theory (DFT) to compare with present experimental results. Our calculated values of EFG are found to be in close agreement with the experimental results. No magnetic interactions in Zr2Ni7 have been observed at 298 and 77 K which implies that there is no ferromagnetic ordering in this material down to 77 K. This observation is corroborated by theoretical calculations, wherein no magnetic moment or hyperfine field is found at any atomic site.

Dey, C. C.; Srivastava, S. K.

2013-10-01

136

Lunar magnetic field - Permanent and induced dipole moments

NASA Technical Reports Server (NTRS)

Apollo 15 subsatellite magnetic field observations have been used to measure both the permanent and the induced lunar dipole moments. Although only an upper limit of 1.3 x 10 to the 18th gauss-cubic centimeters has been determined for the permanent dipole moment in the orbital plane, there is a significant induced dipole moment which opposes the applied field, indicating the existence of a weak lunar ionosphere.

Russell, C. T.; Coleman, P. J., Jr.; Schubert, G.

1974-01-01

137

Electric dipole moment searches: reexamination of frequency shifts for particles in traps

In experiments searching for a nonzero electric dipole moment of trapped particles, frequency shifts correlated with an applied electric field can be interpreted as a false signal. One such effect, referred to as the geometric phase effect, is known to occur in a magnetic field that is nonperfectly homogeneous. The increase in sensitivity of experiments demands improved theoretical description of this effect. In the case of fast particles, like atoms at room temperature and low pressure, the validity of established theories was limited to a cylindrical confinement cell in a uniform gradient with cylindrical symmetry. We develop a more general theory valid for an arbitrary shape of the magnetic field as well as for arbitrary geometry of the confinement cell. Our improved theory is especially relevant for experiments measuring the neutron electric dipole moment with an atomic comagnetometer. In this context, we have reproduced and extended earlier numerical studies of the geometric phase effect induced by localized magnetic impurities.

Guillaume Pignol; Stephanie Roccia

2012-05-02

138

Magnets and Electricity - Creating Magnetism with Electricity

NSDL National Science Digital Library

This cooperative classroom activity will allow students to apply their knowledge of magnetism and electricity. The students will create a circuit that lights a flashlight bulb and simultaneously practice the skills of prediction, observation, inferrence, recording, investigation and communication.

139

The Proton Electric Pygmy Dipole Resonance

The evolution of the low-lying E1 strength in proton-rich nuclei is analyzed in the framework of the self-consistent relativistic Hartree-Bogoliubov (RHB) model and the relativistic quasiparticle random-phase approximation (RQRPA). Model calculations are performed for a series of N=20 isotones and Z=18 isotopes. For nuclei close to the proton drip-line, the occurrence of pronounced dipole peaks is predicted in the low-energy region below 10 MeV excitation energy. From the analysis of the proton and neutron transition densities and the structure of the RQRPA amplitudes, it is shown that these states correspond to the proton pygmy dipole resonance.

N. Paar; D. Vretenar; P. Ring

2005-05-06

140

Measurement of the Electron Electric Dipole Moment using GdIG

Recently, there has been renewed interest in the possibility of using a solid-state system to measure the electron electric dipole moment (edm) [1]. A new measurement of the electron edm using gadolinium iron garnet (GdIG) is now underway and will be discussed. GdIG is a soft magnetic dielectric with a strong temperature-dependent contribution to its magnetization from paramagnetic gadolinium ions.

Larry Hunter

2004-01-01

141

Demonstration of a Cold Atom Fountain Electron Electric Dipole Moment Experiment

A Cs fountain electron electric dipole moment (EDM) experiment using electric-field quantization is demonstrated. With magnetic fields reduced to 200 pT or less, the electric field lifts the degeneracy between hyperfine levels of different|mF| and, along with the slow beam and fountain geometry, suppresses systematics from motional magnetic fields. Transitions are induced and the atoms polarized and analyzed in field-free regions. The feasibility of reaching a sensitivity to an electron EDM of 2 x 10 exp(-50) C-m [1.3 x 10 exp(-29) e-cm] in a cesium fountain experiment is discussed.

Jason M. Amini; Charles T. Munger Jr.; Harvey Gould

2006-03-14

142

The Levitated Dipole Experiment (LDX) is the first experiment of its kind to use a levitated current ring to confine a plasma in a dipole magnetic field. Unlike most other confinement devices, plasma compressibility ...

Karim, Ishtak

2007-01-01

143

NEUTRON ELECTRIC-DIPOLE MOMENT, ULTRACOLD NEUTRONS

operations on the Pauli 4.4. Effect of an x-component of the static matrices 57 magnetic field 30 Appendix B of the effects of the dc magnetic experiment 51 field by means of"critical dressing" 24 7.1. Overview EDM 25 7.3. Magnetic-field homogeneity requirements 53 4. Quantum analysis of the dressed spin system

144

Dual aperture dipole magnet with second harmonic component

An improved dual aperture dipole electromagnet includes a second-harmonic frequency magnetic guide field winding which surrounds first harmonic frequency magnetic guide field windings associated with each aperture. The second harmonic winding and the first harmonic windings cooperate to produce resultant magnetic waveforms in the apertures which have extended acceleration and shortened reset portions of electromagnet operation.

Praeg, Walter F. (Palos Park, IL)

1985-01-01

145

Observation of Centrifugally Driven Interchange Instabilities in a Laboratory Magnetic Dipole

Centrifugally-driven interchange instabilities are observed in a laboratory plasma confined by a dipole magnetic field. The instabilities are excited when an equatorial mesh is biased to drive a radial current through a plasma created by electron cyclotron resonance heating. The bias produces an axisymmetric radial electric field and azimuthal plasma rotation that can reach sonic speeds. The measured floating potential

Benjamin Levitt

2004-01-01

146

Complete electric dipole response and the neutron skin in 208Pb

A benchmark experiment on 208Pb shows that polarized proton inelastic scattering at very forward angles including 0{\\deg} is a powerful tool for high-resolution studies of electric dipole (E1) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up-to-date nuclear models. The extracted E1 polarizability leads to a neutron skin thickness r_skin = 0.156+0.025-0.021 fm in 208Pb derived within a mean-field model [Phys. Rev. C 81, 051303 (2010)], thereby constraining the symmetry energy and its density dependence, relevant to the description of neutron stars.

A. Tamii; I. Poltoratska; P. von Neumann-Cosel; Y. Fujita; T. Adachi; C. A. Bertulani; J. Carter; M. Dozono; H. Fujita; K. Fujita; K. Hatanaka; A. M. Heilmann; D. Ishikawa; M. Itoh; H. J. Ong; T. Kawabata; Y. Kalmykov; E. Litvinova; H. Matsubara; K. Nakanishi; R. Neveling; H. Okamura; B. Özel-Tashenov; V. Yu. Ponomarev; A. Richter; B. Rubio; H. Sakaguchi; Y. Sakemi; Y. Sasamoto; Y. Shimbara; Y. Shimizu; F. D. Smit; T. Suzuki; Y. Tameshige; J. Wambach; R. Yamada; M. Yosoi; J. Zenihiro

2011-05-30

147

Baryogenesis, electric dipole moments and dark matter in the MSSM

We study the implications for electroweak baryogenesis (EWB) within the minimal supersymmetric Standard Model (MSSM) of present and future searches for the permanent electric dipole moment (EDM) of the electron, for neutralino dark matter, and for supersymmetric particles at high energy colliders. We show that there exist regions of the MSSM parameter space that are consistent with both present two-loop

Vincenzo Cirigliano; Stefano Profumo; Michael J. Ramsey-Musolf

2006-01-01

148

Neutron Electric Dipole Moment from Beyond the Standard Model

We discuss the phenomenology of neutron Electric Dipole Moment from the Standard Model and beyond, and identify the matrix elements most necessary to connect the current and forthcoming experiments with phenomenology. We then describe lattice techniques for calculating these matrix elements

Tanmoy Bhattacharya; Vincenzo Cirigliano; Rajan Gupta

2012-12-20

149

Electric dipole moment cancellations in D-brane models.

We analyze the possibility of simultaneous electron, neutron, and mercury electric dipole moment (EDM) cancellations in the mSUGRA and D-brane models. We find that the mercury EDM constraint practically rules out the cancellation scenario in D-brane models, whereas in the context of mSUGRA it is still allowed with some fine tuning. PMID:11415377

Abel, S; Khalil, S; Lebedev, O

2001-06-25

150

Enhancement of the electron electric dipole moment in gadolinium garnets

Effects caused by the electron electric dipole moment (EDM) in gadolinium garnets are considered. Experimental studies of these effects could improve the current upper limit on the electron EDM by several orders of magnitude. We suggest a consistent theoretical model and perform calculations of observable effects in gadolinium gallium garnet and gadolinium iron garnet. Our calculation accounts for both direct

T. N. Mukhamedjanov; V. A. Dzuba; O. P. Sushkov

2003-01-01

151

a Search for the Electric Dipole Moment of the Electron

We report a new upper limit on the electric dipole moment (EDM) of the electron of d_{ rm e} = 0.1 +\\/- 3.2 times 10^{ -26} e-cm. This precision is one hundred times better than any previously published limit and a factor of two better than that of unofficial reports. Recently there has been a great deal of theoretical interest

Kamal Fuad Abdullah

1989-01-01

152

Reappraisal of the Electric Dipole Moment Enhancement Factor for Thallium

The electric dipole moment (EDM) enhancement factor of atomic Tl is of considerable interest as it has been used in determining the most accurate limit on the electron EDM to date. However, its value varies from -179 to -1041 in different approximations. In view of the large uncertainties associated with many of these calculations, we perform an accurate calculation employing

H. S. Nataraj; B. K. Sahoo; B. P. Das; D. Mukherjee

2011-01-01

153

Enhancement of the electron electric dipole moment in gadolinium garnets

Effects caused by the electron electric dipole moment (EDM) in gadolinium garnets are considered. Experimental studies of these effects could improve the current upper limit on the electron EDM by several orders of magnitude. We suggest a consistent theoretical model and perform calculations of observable effects in gadolinium gallium garnet and gadolinium iron garnet. Our calculation accounts for both direct and exchange diagrams.

Mukhamedjanov, T.N.; Dzuba, V.A.; Sushkov, O.P. [School of Physics, University of New South Wales, Sydney 2052 (Australia)

2003-10-01

154

Enhancement of the electron electric dipole moment in gadolinium garnets

Effects caused by the electron electric dipole moment (EDM) in gadolinium garnets are considered. Experimental studies of these effects could improve current upper limit on the electron EDM by several orders of magnitude. We suggest a consistent theoretical model and perform calculations of observable effects in gadolinium gallium garnet and gadolinium iron garnet. Our calculation accounts for both direct and exchange diagrams.

T. N. Mukhamedjanov; V. A. Dzuba; O. P. Sushkov

2003-01-10

155

NASA Astrophysics Data System (ADS)

Long range dipole-dipole interactions in the thermal fluctuations of the magnetization of an assembly of single-domain ferromagnetic particles are considered, ignoring orientational correlations between the particles, so that the evolution of the magnetization orientations may be described by a nonlinear Fokker-Planck equation (FPE) reducing to the usual linear one in the limit of infinite dilution [W. F. Brown Jr., Phys. Rev. 130, 1677 (1963)]. The thermally activated relaxation time scale of the assembly is estimated, leading to a simple and transparent modification of the axially symmetric asymptotes for the superparamagnetic relaxation time.

Déjardin, Pierre-Michel

2011-12-01

156

SEARCH FOR AN ELECTRIC DIPOLE MOMENT OF THE ELECTRON

Experimental upper limits on the size of an EDM for several elementary ; particles have been found. A summary of these limits is tabulated. Garwin and ; Lederman have suggested that the method used in searchrng for the muon EDM could ; be extcnded to higher accuracy for the electron. The anomalous magnetic dipole ; moment experiment of Schupp et

D. F. Nelson; A. A. Schupp; R. W. Pidd; H. R. Crane

1959-01-01

157

Properties of the superconductor in accelerator dipole magnets

NASA Astrophysics Data System (ADS)

Several aspects of the application of superconductors to high field dipole magnets for particle accelerators are discussed. The attention is focused on the 10 tesla (1 m model) magnet that is envisaged for the future Large Hadron Collider (LHC) accelerator. The basic motivation behind the study is the intention of employing superconductors to their utmost performance. An overview of practical supercomputers, their applications and their impact on high field dipole magnets used for particle accelerators, is presented. The LHC reference design for the dipole magnets is outlined. Several models were used to study the influence of a number of factors in the shape and in particular, the deviation from the shape that is due to the flux flow state. For the investigated extrinsic and intrinsic factors, a classification can be made with respect to the effect on the shape of the characteristic of a multifilamentary wire. The optimization of the coil structure for high field dipole magnets, with respect to the field quality is described. An analytical model for solid and hollow filaments, to calculate the effect of filament magnetization in the quality of the dipole field, is presented.

Teravest, Derk

158

NASA Astrophysics Data System (ADS)

We propose a simple experiment to estimate the magnetic dipole moment of a neodymium disc magnet. The experiment employs a precision digital balance and a 1?m ruler to measure the force between two magnets. The magnetic dipole moment is determined from the slope of the magnetic force as a function of the inverse fourth power of the distance. The presented activity can be performed by teachers and students at college or university level to enhance their knowledge of the physics of magnetism.

Amrani, D.

2015-03-01

159

Resolving Spin-Orbit- and Hyperfine-Mediated Electric Dipole Spin Resonance in a Quantum Dot

NASA Astrophysics Data System (ADS)

We investigate the electric manipulation of a single-electron spin in a single gate-defined quantum dot. We observe that so-far neglected differences between the hyperfine- and spin-orbit-mediated electric dipole spin resonance conditions have important consequences at high magnetic fields. In experiments using adiabatic rapid passage to invert the electron spin, we observe an unusually wide and asymmetric response as a function of the magnetic field. Simulations support the interpretation of the line shape in terms of four different resonance conditions. These findings may lead to isotope-selective control of dynamic nuclear polarization in quantum dots.

Shafiei, M.; Nowack, K. C.; Reichl, C.; Wegscheider, W.; Vandersypen, L. M. K.

2013-03-01

160

Electricity and Magnetic Fields

NSDL National Science Digital Library

The grand challenge for this legacy cycle unit is for students to design a way to help a recycler separate aluminum from steel scrap metal. In previous lessons, they have looked at how magnetism might be utilized. In this lesson, students think about how they might use magnets and how they might confront the problem of turning the magnetic field off. Through the accompanying activity students explore the nature of an electrically induced magnetic field and its applicability to the needed magnet.

VU Bioengineering RET Program,

161

The magnetic dipole interaction in Einstein-Maxwell theory

I derive an exact, static, axially symmetric solution of the Einstein-Maxwell equations representing two massless magnetic dipoles, and compare it with the corresponding solution of Einstein's equations for two massless spinning particles (see gr-qc/0201094). I then obtain an exact stationary solution of the Einstein-Maxwell equations representing two massless spinning magnets in balance. The conclusion is that the spin-spin force is analogous to the force between two magnetic dipoles, but of opposite sign, and that the latter agrees with the classical value in the first approximation.

W. B. Bonnor

2002-03-13

162

Invisible nanowires with interferencing electric and toroidal dipoles

By studying the scattering of normally incident planewaves by a single nanowire, we reveal the indispensable role of toroidal multipole excitation in multipole expansions of radiating sources. It is found that for both p-polarized and s-polarized incident waves, toroidal dipoles can be effectively excited within homogenous dielectric nanowires in the optical spectrum regime. We further demonstrate that the plasmonic core-shell nanowires can be rendered invisible through destructive interference of the electric and toroidal dipoles, which may inspire many nanowire based light-matter interaction studies, and incubate biological and medical applications that require non-invasive detections and measurements.

Liu, Wei; Lei, Bing; Hu, Haojun; Miroshnichenko, Andrey E

2015-01-01

163

Nuclear electric dipole moments for the lowest 1/2+ states in Xe and Ba isotopes

NASA Astrophysics Data System (ADS)

The electric dipole moments for the lowest 1/2+ states of Xe and Ba isotopes are calculated in terms of the nuclear shell model, which includes two-body nucleon interactions violating parity and time-reversal invariance. Using the wave functions thus obtained, the nuclear electric dipole moments arising from the intrinsic nucleon electric dipole moments and also from asymmetric charge distribution are calculated. The upper limits for the nuclear electric dipole moments of Xe and Ba isotopes are estimated.

Yoshinaga, N.; Higashiyama, K.; Arai, R.; Teruya, E.

2014-04-01

164

Do bacteria have an electric permanent dipole moment?

In the scientific literature in the last 40 years, some data for the permanent dipole moment and the electric polarizability of Escherichia coli can be found [S.P. Stoylov, Colloid Electro-Optics - Theory, Techniques and Application, Academic Press, London, 1991]. In this paper the data based mainly on electro-optic investigation is considered as much as some dipolophoretic (most often called dielectrophoretic) studies. Serious grounds are found to doubt the conclusions made for the electric dipole moments of bacteria by one of the authors of this paper (SPS) and by some other researchers. This concerns both the permanent dipole moment and the electric charge dependent polarizabilities of E. coli. Here, along with the discussion of the old experimental data, new experimental data are shown for a strain of E. coli HB101. The conclusions from the analysis of the old and the new experimental data is that they do not provide correct evidence for the presence of a permanent dipole moment. It seems that all statements for the existence of electric permanent dipole moment in bacteria [S.P. Stoylov, Colloid Electro-Optics - Theory, Techniques and Application, Academic Press, London, 1991; S.P. Stoylov, S. Sokerov, I. Petkanchin, N. Ibroshev, Dokl. AN URSS 180 (1968) 1165; N.A. Tolstoy, A.A. Spartakov, A.A. Trusov, S.A. Schelkunova, Biofizika 11 (1966) 453; V. Morris, B. Jennings, J. Chem. Soc. Faraday Trans. II 71 (1975) 1948; V. Morris, B. Jennings, J. Colloid Interface Sci. 55 (1978) 313; S.P. Stoylov, V.N. Shilov, S.S. Dukhin, S. Sokerov, I. Petkanchin, in: S.S. Dukhin (Ed.), Electro-optics of Colloids, Naukova Dumka, Kiev, 1977 (in Russian).] based on electro-optic studies are result of incorrect interpretation. Therefore, they should be further ignored. PMID:18378431

Stoylov, S P; Gyurova, A; Georgieva, R; Danova, S

2008-07-15

165

New Experiment to Measure the Electron Electric Dipole Moment

NASA Technical Reports Server (NTRS)

An electron can possess an electric dipole moment (edm) only if time reversal symmetry (T) is violated. No edm of any particle has yet been discovered. CP-violation, equivalent to T-violation by the CPT theorem, does occur in Kaon decays and can be accounted for by the standard model. However, this mechanism leads to an electron edm d(sub e) of the order of 10(exp -38) e cm, whereas the current experimental bound on d(sub e) is about 10(exp -27) e cm. However, well-motivated extensions of the standard model such as supersymmetric theories do predict that de could be as large as the current bound. In addition, CP violation in the early universe is required to explain the preponderance of matter over anti-matter, but the exact mechanism of this CP violation is unclear. For these reasons, we are undertaking a new experimental program to determine de to an improved accuracy of 10(exp -29) e cm. Our experiment will use laser-cooled, trapped Cesium atoms to measure the atomic edm d(sub Cs) that occurs if d(sub e) is not zero. In order to do this, we will measure the energy splitting between the atoms spin states in parallel electric and magnetic fields. The signature of an edm would be a linear dependence of the splitting on the electric field E due to the interaction - d(sub Cs) dot E. Our measurement will be much more sensitive than previous measurements because atoms can be stored in the trap for tens of seconds, allowing for much narrower Zeeman resonance linewidths. Also, our method eliminates the most important systematic errors, proportional to atomic velocity, which have limited previous experiments. In this presentation, we will describe the design of our new apparatus, which is presently under construction. An important feature of our experimental apparatus is that magnetic field noise will be suppressed to a very low value of the order of 1 fT/(Hz)1/2. This requires careful attention to the Johnson noise currents in the chamber, which have not been important in previous experiments. In addition we will present estimates of the limits of the various errors that we expect for our experiment.

Kittle, Melanie

2003-01-01

166

Enhancement of the Electric Dipole Moment of the Electron in PbO M. G. Kozlov*

]. That started a long search for the electric dipole moment (EDM) of the electron de in atomic experiments [2Enhancement of the Electric Dipole Moment of the Electron in PbO M. G. Kozlov* Petersburg Nuclear to measure the electric dipole moment of the electron de. We discuss a semiempirical model for this state

Kozlov, Mikhail G

167

Limit on the electron electric dipole moment in gadolinium-iron garnet.

A new method for the detection of the electron electric dipole moment (EDM) using a solid is described. The method involves the measurement of a voltage induced across the solid by the alignment of the sample's magnetic dipoles in an applied magnetic field, H. A first application of the method to GdIG has resulted in a limit on the electron EDM of 5 x 10(-24)e cm, which is a factor of 40 below the limit obtained from the only previous solid-state EDM experiment. The result is limited by the imperfect discrimination of an unexpectedly large voltage that is even upon the reversal of the sample magnetization. PMID:16384457

Heidenreich, B J; Elliott, O T; Charney, N D; Virgien, K A; Bridges, A W; McKeon, M A; Peck, S K; Krause, D; Gordon, J E; Hunter, L R; Lamoreaux, S K

2005-12-16

168

CP violation Beyond the MSSM: Baryogenesis and Electric Dipole Moments

We study electroweak baryogenesis and electric dipole moments in the presence of the two leading-order, non-renormalizable operators in the Higgs sector of the MSSM. Significant qualitative and quantitative differences from MSSM baryogenesis arise due to the presence of new CP-violating phases and to the relaxation of constraints on the supersymmetric spectrum (in particular, both stops can be light). We find: (1) spontaneous baryogenesis, driven by a change in the phase of the Higgs vevs across the bubble wall, becomes possible; (2) the top and stop CP-violating sources can become effective; (3) baryogenesis is viable in larger parts of parameter space, alleviating the well-known fine-tuning associated with MSSM baryogenesis. Nevertheless, electric dipole moments should be measured if experimental sensitivities are improved by about one order of magnitude.

Kfir Blum; Cedric Delaunay; Marta Losada; Yosef Nir; Sean Tulin

2010-03-11

169

Higgs-Higgsino-gaugino induced two loop electric dipole moments

We compute the complete set of Higgs-mediated chargino-neutralino two-loop contributions to the electric dipole moments of the electron and neutron in the minimal supersymmetric standard model (MSSM). We study the dependence of these contributions on the parameters that govern CP-violation in the MSSM gauge-gaugino-Higgs-Higgsino sector. We find that contributions mediated by the exchange of WH{sup {+-}} and ZA{sup 0} pairs, where H{sup {+-}} and A{sup 0} are the charged and CP-odd Higgs scalars, respectively, are comparable to or dominate over those mediated by the exchange of neutral gauge bosons and CP-even Higgs scalars. We also emphasize that the result of this complete set of diagrams is essential for the full quantitative study of a number of phenomenological issues, such as electric dipole moment searches and their implications for electroweak baryogenesis.

Li Yingchuan [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Profumo, Stefano [Department of Physics and Santa Cruz Institute for Particle Physics, University of California, 1156 High Street, Santa Cruz, California 95064 (United States); Ramsey-Musolf, Michael [Department of Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States); Kellogg Radiation Laboratory, California Institute of Technology, Pasadena, California 91125 (United States)

2008-10-01

170

Enhancement of the electron electric dipole moment in gadolinium 3+

There have been recent suggestions for searching for the electron electric dipole moment, using solid state experiments with compounds containing Gd 3+ ions. These experiments could improve the sensitivity compared to present atomic and molecular experiments by several orders of magnitude. The analysis of the problem requires a calculation of the enhancement coefficient K for the electron electric dipole moment in the Gd 3+ ion. In this work we perform this calculation. The result is K = -4.9 +- 1.6. Limitations of the accuracy of the calculation are mainly due to the lack of data on Gd 3+ excitation spectra. We formulate which quantities have to be measured and/or calculated to improve the accuracy.

S. Y. Buhmann; V. A. Dzuba; O. P. Sushkov

2002-04-25

171

This paper presents preliminary results of magnetic field measurements made on a series of 50 mm aperture 15 m long SSC collider dipole magnets designed and manufactured at Fermi National Accelerator Laboratory (Fermilab) for use in the Superconducting Super Collider Laboratory (SSCL) Accelerator System String Test. The magnets were assembled by Fermilab and General Dynamics personnel, and were tested at the Magnet Test Facility (MTF) at Fermilab. Measurements of the dipole field angle, dipole field strength, and field shape parameters at various stages in magnet construction and testing are described.

Delchamps, S.; Bleadon, M.; Bossert, R.; Carson, J.; Gourlay, S.; Hanft, R.; Koska, W.; Kuchnir, M.; Lamm, M.; Mazur, P.; Mokhtarani, A.; Orris, D.; Strait, J.; Wake, M. (Fermi National Accelerator Lab., Batavia, IL (United States)); Devred, A.; DiMarco, J.; Kuzminski, J.; Ogitsu, T.; Puglisi, M.; Tompkins, J.; Yu, Y.; Zhao, Y.; Zheng, H. (Superconducting Super Collider Lab., Dallas, TX (United States))

1992-04-01

172

A cosmological lower bound on the neutron electric dipole moment

We argue that in a wide class of grand unified theories diagrams similar to those generating baryon number in the early universe also contribute to renormalization of the CP-violating theta parameter of QCD and hence to the neutron electric dipole moment dn. We then use the apparent baryon-to-photon ratio (nB\\/ngamma) >~ 1.3 × 10-10 to deduce an order-of-magnitude lower bound

John Ellis; Mary K. Gaillard; D. V. Nanopoulos; Serge Rudaz

1981-01-01

173

Electric Dipole Moment in the Split Supersymmetry Models

We study an important contribution to the electric dipole moment (EDM) of the electron (or quarks) at the two-loop level due to the $W$-EDM in the recently proposed scenario of split supersymmetry. This contribution is independent of the Higgs mass, and it can enhance the previous estimation of the electron (neutron) EDM by $20-50%$ ($40-90%$). Our formula is new in its analytical form.

Darwin Chang; We-Fu Chang; Wai-Yee Keung

2005-04-12

174

Intrinsic Electric Dipole Moments of Paramagnetic Atoms: Rubidium and Cesium

The electric dipole moment (EDM) of paramagnetic atoms is sensitive to the intrinsic EDM contribution from that of its constituent electrons and a scalar-pseudoscalar (S-PS) electron-nucleus interaction. The electron EDM and the S-PS contributions to the EDMs of these atoms scale as ≈Z3. Thus, the heavy paramagnetic atoms will exhibit large EDM enhancement factors. However, the sizes of the couplings

H. S. Nataraj; B. K. Sahoo; B. P. Das; D. Mukherjee

2008-01-01

175

Electric dipole moments in the MSSM at large tan ?

Within the minimal supersymmetric standard model (MSSM), the large tan? regime can lead to important modifications in the pattern of CP-violating sources contributing to low energy electric dipole moments (EDMs). In particular, four-fermion CP-violating interactions induced by Higgs exchange should be accounted for alongside the constituent EDMs of quarks and electrons. To this end, we present a comprehensive analysis of

Durmus Demir; Oleg Lebedev; Keith A. Olive; Maxim Pospelov; Adam Ritz

2004-01-01

176

Electric dipole moment in the split supersymmetry models

We study an important contribution to the electric dipole moment (EDM) of the electron (or quarks) at the two-loop level due to the W-EDM in the recently proposed scenario of split supersymmetry. This contribution is independent of the Higgs mass, and it can enhance the previous estimation of the electron (neutron) EDM by 20-50% (40-90%). Our formula is new in its analytical form.

Chang, Darwin; Chang, W.-F.; Keung, W.-Y. [Physics Department, National TsingHua University, Hsinchu 300, Taiwan (China); Institute of Physics, Academia Sinica, Taipei 115, Taiwan (China); Physics Department, University of Illinois, Chicago, Illinois 60607-7059 (United States)

2005-04-01

177

A search for the electric dipole of the electron

A new upper limit is reported on the electric dipole moment (EDM) of the electron of d(sub e) = 0.1 (plus minus) 3.2 x 10(exp -26) e\\/cm. This precision is one hundred times better than any previously published limit and a factor of two better than that of unofficial reports. Recently there has been a great deal of theoretical interest

Kamal Fuad Abdullah

1989-01-01

178

Electric dipole polarizabilities of hydrogen and helium isotopes

The electric dipole polarizabilities of H3, He3, and He4 are calculated directly using the Schrödinger equation with the latest generation of two- and three-nucleon interactions. These polarizabilities are necessary to obtain accurate nuclear-polarization corrections for transitions involving S waves in one- and two-electron atoms. Our results are compared to previous results, and it is shown that direct calculations of the

I. Stetcu; S. Quaglioni; J. L. Friar; A. C. Hayes; Petr Navrátil

2009-01-01

179

Electric Dipole Moments of Rare-Gas Diatomic Molecules

Electric dipole moment and interatomic potential functions are computed for the diatomic systems HeNe, HeAr, and NeAr, in the molecular Hartree-Fock approximation. Since this approximation does not include a description of dispersion forces, the potential curves are purely repulsive. The potential and moment functions can all be fitted closely by simple exponential functions over the range of internuclear distances considered,

R. L. Matcha; R. K. Nesbet

1967-01-01

180

Plasma stability in a dipole magnetic field

The MHD and kinetic stability of an axially symmetric plasma, confined by a poloidal magnetic field with closed lines, is considered. In such a system the stabilizing effects of plasma compression and magnetic field ...

Simakov, Andrei N., 1974-

2001-01-01

181

Reexamination of The Standard Model Nucleon Electric Dipole Moment

The Cabibbo-Kobayashi-Maskawa matrix in the Standard Model is currently the only experimentally-confirmed source of CP-violation. The intrinsic electric dipole moment of the nucleon induced by this CP-phase via hadronic loop and pole diagrams has been studied more than two decades ago, but the existing calculation is subject to various theoretical issues such as the breakdown of chiral power counting and uncertainties in the determination of low energy constants. We carry out an up-to-date re-analysis on both one-loop and pole diagram contributions to the nucleon electric dipole moment based on Heavy Baryon Chiral Perturbation Theory in a way that preserves power counting, and redo the determination of the low energy constants following the results of more recent articles. Combined with an estimation of higher-order contributions, we expect the long-distance contribution to the Standard Model nucleon electric dipole moment to be approximately $(1\\times10^{-32}-6\\times10^{-32})e\\,\\mathrm{cm}$.

Chien-Yeah Seng

2015-02-06

182

Canted-spin-caused electric dipoles: A local symmetry theory

NASA Astrophysics Data System (ADS)

A pair of magnetic atoms with canted spins Sa,Sb can give rise to an electric dipole moment P. Several forms for the behavior of such a moment have appeared in the theoretical literature, some of which have been invoked to explain experimental results found in various multiferroic materials. The forms that require canting of the spins are P1?R×(Sa×Sb),P2?Sa×Sb, and P3?SaR·Sa-SbR·Sb, where R is the relative position of the atoms and Sa,Sb are unit vectors. To unify and generalize these various forms, we consider P as the most general quadratic function of the spin components that vanishes whenever Sa and Sb are collinear, i.e., we consider the most general expressions that require spin canting. The study reveals new forms. We generalize to the vector P, Moriyas symmetry considerations regarding the (scalar) Dzyaloshinskii-Moriya energy D·Sa×Sb (which led to restrictions on D). This provides a rigorous symmetry argument that shows that P1 is allowed no matter how high the symmetry of the atoms plus environment, and gives restrictions for all other contributions. The analysis leads to the suggestion of terms omitted in the existing microscopic models, suggests a new mechanism behind the ferroelectricity found in the proper screw structure of CuXO2, X=Fe,Cr, and predicts an unusual antiferroelectric ordering in the antiferromagnetically and ferroelectrically ordered phase of RbFe(MoO4)2.

Kaplan, T. A.; Mahanti, S. D.

2011-05-01

183

Self-generated magnetic dipoles in weakly magnetized beam-plasma system

NASA Astrophysics Data System (ADS)

A self-generation mechanism of magnetic dipoles and the anomalous energy dissipation of fast electrons in a magnetized beam-plasma system are presented. Based on two-dimensional particle-in-cell simulations, it is found that the magnetic dipoles are self-organized and play important roles in the beam electron energy dissipation. These dipoles drift slowly in the direction of the return flow with a quasisteady velocity, which depends upon the magnetic amplitude of the dipole and the imposed external magnetic field. This dipole formation provides a mechanism for the anomalous energy dissipation of a relativistic electron beam, which would play an important role in collisionless shock and ion shock acceleration.

Jia, Qing; Mima, Kunioki; Cai, Hong-bo; Taguchi, Toshihiro; Nagatomo, Hideo; He, X. T.

2015-02-01

184

Probing electric and magnetic vacuum fluctuations with quantum dots

The electromagnetic-vacuum-field fluctuations are intimately linked to the process of spontaneous emission of light. Atomic emitters cannot probe electric- and magnetic-field fluctuations simultaneously because electric and magnetic transitions correspond to different selection rules. In this paper we show that semiconductor quantum dots are fundamentally different and are capable of mediating electric-dipole, magnetic-dipole, and electric-quadrupole transitions on a single electronic resonance. As a consequence, quantum dots can probe electric and magnetic fields simultaneously and can thus be applied for sensing the electromagnetic environment of complex photonic nanostructures. Our study opens the prospect of interfacing quantum dots with optical metamaterials for tailoring the electric and magnetic light-matter interaction at the single-emitter level.

Petru Tighineanu; Mads Lykke Andersen; Anders Sĝndberg Sĝrensen; Sĝren Stobbe; Peter Lodahl

2014-04-04

185

Probing Electric and Magnetic Vacuum Fluctuations with Quantum Dots

NASA Astrophysics Data System (ADS)

The electromagnetic-vacuum-field fluctuations are intimately linked to the process of spontaneous emission of light. Atomic emitters cannot probe electric- and magnetic-field fluctuations simultaneously because electric and magnetic transitions correspond to different selection rules. In this Letter we show that semiconductor quantum dots are fundamentally different and are capable of mediating electric-dipole, magnetic-dipole, and electric-quadrupole transitions on a single electronic resonance. As a consequence, quantum dots can probe electric and magnetic fields simultaneously and can thus be applied for sensing the electromagnetic environment of complex photonic nanostructures. Our study opens the prospect of interfacing quantum dots with optical metamaterials for tailoring the electric and magnetic light-matter interaction at the single-emitter level.

Tighineanu, P.; Andersen, M. L.; Sĝrensen, A. S.; Stobbe, S.; Lodahl, P.

2014-07-01

186

Electric dipole moments of nanosolvated acid molecules in water clusters.

The electric dipole moments of (H2O)nDCl (n=3-9) clusters have been measured by the beam-deflection method. Reflecting the (dynamical) charge distribution within the system, the dipole moment contributes information about the microscopic structure of nanoscale solvation. The addition of a DCl molecule to a water cluster results in a strongly enhanced susceptibility. There is evidence for a noticeable rise in the dipole moment occurring at n?5-6. This size is consistent with predictions for the onset of ionic dissociation. Additionally, a molecular-dynamics model suggests that even with a nominally bound impurity an enhanced dipole moment can arise due to the thermal and zero-point motion of the proton and the water molecules. The experimental measurements and the calculations draw attention to the importance of fluctuations in defining the polarity of water-based nanoclusters and generally to the essential role played by motional effects in determining the response of fluxional nanoscale systems under realistic conditions. PMID:25679889

Guggemos, Nicholas; Slaví?ek, Petr; Kresin, Vitaly V

2015-01-30

187

Electric Dipole Moments of Nanosolvated Acid Molecules in Water Clusters

NASA Astrophysics Data System (ADS)

The electric dipole moments of (H2O)nDCl (n =3 - 9 ) clusters have been measured by the beam-deflection method. Reflecting the (dynamical) charge distribution within the system, the dipole moment contributes information about the microscopic structure of nanoscale solvation. The addition of a DCl molecule to a water cluster results in a strongly enhanced susceptibility. There is evidence for a noticeable rise in the dipole moment occurring at n ?5 - 6 . This size is consistent with predictions for the onset of ionic dissociation. Additionally, a molecular-dynamics model suggests that even with a nominally bound impurity an enhanced dipole moment can arise due to the thermal and zero-point motion of the proton and the water molecules. The experimental measurements and the calculations draw attention to the importance of fluctuations in defining the polarity of water-based nanoclusters and generally to the essential role played by motional effects in determining the response of fluxional nanoscale systems under realistic conditions.

Guggemos, Nicholas; Slaví?ek, Petr; Kresin, Vitaly V.

2015-01-01

188

Electric dipole moments of nanosolvated acid molecules in water clusters

The electric dipole moments of $(H_{2}O)_{n}DCl$ ($n=3-9$) clusters have been measured by the beam deflection method. Reflecting the (dynamical) charge distribution within the system, the dipole moment contributes information about the microscopic structure of nanoscale solvation. The addition of a DCl molecule to a water cluster results in a strongly enhanced susceptibility. There is evidence for a noticeable rise in the dipole moment occurring at $n\\approx5-6$. This size is consistent with predictions for the onset of ionic dissociation. Additionally, a molecular dynamics model suggests that even with a nominally bound impurity an enhanced dipole moment can arise due to the thermal and zero point motion of the proton and the water molecules. The experimental measurements and the calculations draw attention to the importance of fluctuations in defining the polarity of water-based nanoclusters, and generally to the essential role played by motional effects in determining the response of fluxional nanoscale sy...

Guggemos, Nicholas; Kresin, Vitaly V

2015-01-01

189

Transmission of electric dipole radiation through an interface

NASA Astrophysics Data System (ADS)

We consider the transmission of electric dipole radiation through an interface between two dielectrics, for the case of a vertical dipole. Energy flows along the field lines of the Poynting vector, and in the optical near field these field lines are curves (as opposed to optical rays). When the radiation passes through the interface into a thicker medium, the field lines bend to the normal (as rays do), but the transmission angle is not related to the angle of incidence. The redirection of the radiation at the interface is determined by the angle dependence of the transmission coefficient. This near-field redistribution is responsible for the far-field angular power pattern. When the transmission medium is thinner than the embedding medium of the dipole, some energy flows back and forth through the interface in an oscillating fashion. In each area where field lines dip below the interface, an optical vortex appears just above the interface. The centers of these vortices are concentric singular circles around the dipole axis.

Arnoldus, Henk F.; Berg, Matthew J.; Li, Xin

2014-02-01

190

Pressure profiles of plasmas confined in the field of a magnetic dipole

Equilibrium pressure profiles of plasmas confined in the field of a dipole magnet are reconstructed using magnetic and x-ray measurements on the levitated dipole experiment (LDX). LDX operates in two distinct modes: with ...

Davis, Matthew S

191

SUPERCONDUCTING DIPOLE MAGNETS FOR THE LHC INSERTION REGIONS

Dipole bending magnets are required to change the horizontal separation of the two beams in the LHC. In Intersection Regions (IR) 1, 2, 5, and 8, the beams are brought into collision for the experiments located there. In IR4, the separation of the beams is increased to accommodate the machine's particle acceleration hardware. As part of the US contribution to

E. WILLEN; M. ANERELLA; J. COZZOLINO; G. GANETIS; A. GHOSH; R. GUPTA; M. HARRISON; A. JAIN; A. MARONE; J. MURATORE; S. PLATE; J. SCHMALZLE; P. WANDERER; K. C. WU

2000-01-01

192

Considerations on the LHCb dipole magnet polarity reversal

The reversal of the LHCb dipole magnet polarity is discussed in light of experience with detection asymmetries in the data collected during 2011 and 2012. The roughly biweekly frequency of polarity changes is considered to be necessary in order to control the detection asymmetries at the 10$^3$ level as needed for many important studies of $CP$ -violation.

Vesterinen, M

2014-01-01

193

The permanent and induced magnetic dipole moment of the moon

NASA Technical Reports Server (NTRS)

Magnetic field observations with the Apollo 15 subsatellite have been used to deduce the components of both the permanent and induced lunar dipole moments in the orbital plane. The present permanent lunar magnetic dipole moment in the orbital plane is less than 1.3 times ten to the eighteenth power gauss-cu cm. Any uniformly magnetized near surface layer is therefore constrained to have a thickness-magnetization product less than 2.5 emu-cm per g. The induced moment opposes the external field, implying the existence of a substantial lunar ionosphere with a permeability between 0.63 and 0.85. Combining this with recent measures of the ratio of the relative field strength at the ALSEP and Explorer 35 magnetometers indicates that the global lunar permeability relative to the plasma in the geomagnetic tail lobes is between 1.008 and 1.03.

Russell, C. T.; Coleman, P. J., Jr.; Lichtenstein, B. R.; Schubert, G.

1974-01-01

194

Local spin torque induced by electron electric dipole moment in the Ybf molecule

NASA Astrophysics Data System (ADS)

In this study, we show the modification of the equation of motion of the electronic spin, which is derived by the quantum electron spin vorticity principle, by the effect of the electron electric dipole moment (EDM). To investigate the new contribution to spin torque by EDM, using first principle calculations, we visualize distributions of the local spin angular momentum density and local spin torque density of the YbF molecule on which the static electric field and magnetic field are applied at t = 0.

Fukuda, Masahiro; Senami, Masato; Ogiso, Yoji; Tachibana, Akitomo

2014-10-01

195

Local spin torque induced by electron electric dipole moment in the YbF molecule

In this study, we show the modification of the equation of motion of the electronic spin, which is derived by the quantum electron spin vorticity principle, by the effect of the electron electric dipole moment (EDM). To investigate the new contribution to spin torque by EDM, using first principle calculations, we visualize distributions of the local spin angular momentum density and local spin torque density of the YbF molecule on which the static electric field and magnetic field are applied at t = 0.

Fukuda, Masahiro; Senami, Masato; Ogiso, Yoji; Tachibana, Akitomo [Department of Micro Engineering, Kyoto University, Kyoto 615-8540 (Japan)

2014-10-06

196

Study By Spin Tracking of A Storage Ring For Deuteron Electric Dipole Moment

Spin tracking of polarized deuterons for a proposed experiment to measure a possible Electric Dipole Moment (EDM) of the deuteron was done by using the codes UAL and SPINK. In the experiment the direction of spin polarization will be frozen using crossed electric and magnetic fields. Systematics, in particular the effects of non-linearities of the lattice on a beam with finite emittance and energy spread, have been extensively simulated and the effect of sextuple corrections to increase the spin coherence time has been studied.

Lin, F.; Malitsky, N. D.; Luccio, A. U.; Morse, W. M.; Semertzidis, Y. K. [Brookhaven National Laboratory, Upton, NY (United States); Onderwater, C. J. G. [University of Groningen, NL-9747AA Groningen (Netherlands); Orlov, Y. F. [Cornell University, Ithaca, NY (United States)

2009-08-04

197

A new experimental limit on the electric dipole moment of the electron

We describe a search for the electric dipole moment d{sub e} of the electron, carried out with {sup 205}Tl atoms in the ground state. The experiment makes use of the separated-oscillating-field magnetic-resonance method, laser state selection, fluorescence detection, and two counter-propagating atomic beams. Very careful attention is paid to systematic effects. The result for the atomic electric dipole moment is d{sub a} = (1.6 {plus minus} 5.0) {times} 10{sup {minus}24} e cm. If we assume the theoretical ratio d{sub a}/d{sub e} = {minus}600, this yields d{sub e} = ({minus}2.7 {plus minus} 8.3) {times} 10{sup {minus}27} e cm. 17 refs., 7 figs., 1 tab.

Carlberg, C.; Gould, H. (Lawrence Berkeley Lab., CA (USA)); Abdullah, K.; Commins, E.D.; Ross, S.B. (Lawrence Berkeley Lab., CA (USA) California Univ., Berkeley, CA (USA). Dept. of Physics)

1990-12-01

198

Four-layer, two-inch bore, superconducting dipole magnet

Superconductors provide the accelerator designer with a unique opportunity to construct machines that can achieve high particle energies and yet have low operating costs. This paper describes the design, fabrication and testing of a 4 layer, 50 mm bore superconducting dipole magnet, D-9A. The magnet reached short sample, 5.8 T at 4.4 K and 8.0 T and 1.8 K, with little training, and exhibited low losses and low ramp rate sensitivity.

Hassenzahl, W.V.; Peters, C.; Gilbert, W.; Taylor, C.; Meuser, R.

1982-11-01

199

Constraining the neutrino magnetic dipole moment from white dwarf pulsations

NASA Astrophysics Data System (ADS)

Pulsating white dwarf stars can be used as astrophysical laboratories to constrain the properties of weakly interacting particles. Comparing the cooling rates of these stars with the expected values from theoretical models allows us to search for additional sources of cooling due to the emission of axions, neutralinos, or neutrinos with magnetic dipole moment. In this work, we derive an upper bound to the neutrino magnetic dipole moment (??) using an estimate of the rate of period change of the pulsating DB white dwarf star PG 1351+489. We employ state-of-the-art evolutionary and pulsational codes which allow us to perform a detailed asteroseismological period fit based on fully DB white dwarf evolutionary sequences. Plasmon neutrino emission is the dominant cooling mechanism for this class of hot pulsating white dwarfs, and so it is the main contributor to the rate of change of period with time (Pi dot) for the DBV class. Thus, the inclusion of an anomalous neutrino emission through a non-vanishing magnetic dipole moment in these sequences notably influences the evolutionary timescales, and also the expected pulsational properties of the DBV stars. By comparing the theoretical Pi dot value with the rate of change of period with time of PG 1351+489, we assess the possible existence of additional cooling by neutrinos with magnetic dipole moment. Our models suggest the existence of some additional cooling in this pulsating DB white dwarf, consistent with a non-zero magnetic dipole moment with an upper limit of ?? lesssim 10-11 ?B. This bound is somewhat less restrictive than, but still compatible with, other limits inferred from the white dwarf luminosity function or from the color-magnitude diagram of the Globular cluster M5. Further improvements of the measurement of the rate of period change of the dominant pulsation mode of PG 1351+489 will be necessary to confirm our bound.

Córsico, A. H.; Althaus, L. G.; Miller Bertolami, M. M.; Kepler, S. O.; García-Berro, E.

2014-08-01

200

Isospin properties of electric dipole excitations in 48Ca

NASA Astrophysics Data System (ADS)

Two different experimental approaches were combined to study the electric dipole strength in the doubly-magic nucleus 48Ca below the neutron threshold. Real-photon scattering experiments using bremsstrahlung up to 9.9 MeV and nearly mono-energetic linearly polarized photons with energies between 6.6 and 9.51 MeV provided strength distribution and parities, and an (?,???) experiment at E?=136 MeV gave cross sections for an isoscalar probe. The unexpected difference observed in the dipole response is compared to calculations using the first-order random-phase approximation and points to an energy-dependent isospin character. A strong isoscalar state at 7.6 MeV was identified for the first time supporting a recent theoretical prediction.

Derya, V.; Savran, D.; Endres, J.; Harakeh, M. N.; Hergert, H.; Kelley, J. H.; Papakonstantinou, P.; Pietralla, N.; Ponomarev, V. Yu.; Roth, R.; Rusev, G.; Tonchev, A. P.; Tornow, W.; Wörtche, H. J.; Zilges, A.

2014-03-01

201

Top quark electric and chromo electric dipole moments in the general two Higgs Doublet model

We study the electric and chromo electric dipole moment of top quark in the general two Higgs Doublet model (model III). We analyse the dependency of this quantity to the new phases coming from the complex Yukawa couplings and masses of charged and neutral Higgs bosons. We observe that the electric and chromo elecric dipole moments of top quark are at the order of 10^{-21} e cm and 10^{-20} g_s cm, which are extremely large values compared to ones calculated in the SM and also two Higgs Doublet model with real Yukawa couplings.

E. O. Iltan

2002-02-11

202

Capacitive Stress Gauges in Model Dipole Magnets

Capacitive transducers are used to measure mechanical stress in the windings of superconducting magnets. The transducer consists of a bonded laminate of alternating thin foils of stainless steel and high-strength polymer (polyimide). The thin...

Ragland, R. Blake

2009-06-09

203

Heavy polar molecules can be used to measure the electric dipole moment of the electron, which is a sensitive probe of physics beyond the Standard Model. The value is determined by measuring the precession of the molecule's spin in a plane perpendicular to an applied electric field. The longer this precession evolves coherently, the higher the precision of the measurement.

M. R. Tarbutt; J. J. Hudson; B. E. Sauer; E. A. Hinds

2009-01-01

204

New Experimental Limit on the Electric Dipole Moment of the Electron in a Paramagnetic Insulator

We report results of an experimental search for the intrinsic Electric Dipole Moment (EDM) of the electron using a solid-state technique. The experiment employs a paramagnetic, insulating gadolinium gallium garnet (GGG) that has a large magnetic response at low temperatures. The presence of the eEDM would lead to a small but non-zero magnetization as the GGG sample is subject to a strong electric field. We search for the resulting Stark-induced magnetization with a sensitive magnetometer. Recent progress on the suppression of several sources of background allows the experiment to run free of spurious signals at the level of the statistical uncertainties. We report our first limit on the eEDM of $(-5.57 \\pm 7.98 \\pm 0.12)\\times10^{-25}$e$\\cdot$cm with 5 days of data averaging.

Y. J. Kim; C. -Y. Liu; S. K. Lamoreaux; G. Visser; B. Kunkler; A. V. Matlashov; B. Kunkler

2011-04-22

205

Experimental search for the electron Electric Dipole Moment using solid state techniques

NASA Astrophysics Data System (ADS)

We report results of an experimental search for the permanent Electric Dipole Moment (EDM) of the electron using a solid state system. The experiment uses a paramagnetic insulator (gadolinium gallium garnet) with a large magnetic response at low temperatures. The presence of the electron EDM leads to a finite magnetization when the garnet sample is subjected to a strong electric field. The resulting magnetization can be measured using a superconducting quantum interference device (SQUID) as a magnetometer. With considerable efforts made towards controlling various sources of systematic effects, the experiment is currently free of spurious signals larger than the SQUID noise. We report the value of electron EDM of (-5.57 ħ 7.98 ħ 0.12) × 10-25e-cm with 120 hours of data.

Kim, Y. J.; Liu, C.-Y.; Lamoreaux, S. K.; Reddy, G.

2011-09-01

206

Candidate molecular ions for an electron electric dipole moment experiment

This paper is a theoretical work in support of a newly proposed experiment [R. Stutz and E. Cornell, Bull. Am. Soc. Phys. 89, 76 (2004)] that promises greater sensitivity to measurements of the electron's electric dipole moment (EDM) based on the trapping of molecular ions. Such an experiment requires the choice of a suitable molecule that is both experimentally feasible and possesses an expectation of a reasonable EDM signal. We find that the molecular ions PtH{sup +} and HfH{sup +} are both suitable candidates in their low-lying {sup 3}{delta} states. In particular, we anticipate that the effective electric fields generated inside these molecules are approximately 73 and -17 GV/cm, respectively. As a byproduct of this discussion, we also explain how to make estimates of the size of the effective electric field acting in a molecule, using commercially available nonrelativistic molecular structure software.

Meyer, Edmund R.; Bohn, John L.; Deskevich, Michael P. [Department of Physics, JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309-0440 (United States); Department of Chemistry and Biochemistry, JILA, National Institute of Standards and Technology and University of Colorado, Boulder, Colorado 80309-0440 (United States)

2006-06-15

207

Coil end design for the SSC collider dipole magnet

This paper describes the design of the coil end for the 50mm aperture SSC collider dipole magnets built at Fermilab. The cable paths are determined from both magnetic and mechanical considerations. The end spacers are designed using the developable surface, grouped end approach, which allows the analysis of strain energy within the conductor groups. Techniques for strain energy minimization are presented and the behavior of individual conductors within a group is analyzed. The relationship between optimization of magnetic and mechanical variables is discussed. Requirements of manufacturing and inspection of coil end parts are outlined. 7 refs.

Brandt, J.; Bartlett, N.; Bossert, R.; Carson, J.; Konc, J.; Lee, G. (Fermi National Accelerator Lab., Batavia, IL (United States)); Cook, J. (Argonne National Lab., IL (United States)); Caspi, S. (Lawrence Berkeley Lab., CA (United States)); Gordon, M.; Nobrega, F. (Superconducting Super Collider Lab., Dallas, TX (United States))

1991-07-01

208

Magnetic dipole moment determination by near-field analysis

NASA Technical Reports Server (NTRS)

A method for determining the magnetic moment of a spacecraft from magnetic field data taken in a limited region of space close to the spacecraft. The spacecraft's magnetic field equations are derived from first principles. With measurements of this field restricted to certain points in space, the near-field equations for the spacecraft are derived. These equations are solved for the dipole moment by a least squares procedure. A method by which one can estimate the magnitude of the error in the calculations is also presented. This technique was thoroughly tested on a computer. The test program is described and evaluated, and partial results are presented.

Eichhorn, W. L.

1972-01-01

209

Shell Model Estimate of Nuclear Electric Dipole Moments

NASA Astrophysics Data System (ADS)

Nuclear electric dipole moments (EDMs) and Schiff moments for the lowest 1/2^+ states around the mass 130 are calculated in terms of the nuclear shell model. We estimate the upper limits of the nuclear EDMs, which may be directly measured through ionic atoms. The nuclear EDM of each nucleus is slightly quenched from its single-particle estimate due to many-body effects. We also estimate the upper limit for the EDM of neutral ^{129}Xe atom using the Schiff moment.

Yoshinaga, N.; Higashiyama, K.; Arai, R.

2010-12-01

210

T violation in radiative $\\beta$ decay and electric dipole moments

In radiative $\\beta$ decay, $T$ violation can be studied through a spin-independent $T$-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of $T$-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the $T$-odd BSM physics in radiative $\\beta$ decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent $T$-odd correlation in radiative $\\beta$ decay.

Dekens, W G

2015-01-01

211

Parity-violating electric-dipole transitions in helium

NASA Technical Reports Server (NTRS)

The paper examines parity-violating electric-dipole transitions in He in order to gain insight into the reliability of approximate calculations which are carried out for transitions in many-electron atoms. The contributions of the nearest-lying states are computed with a variety of wave functions, including very simple product wave functions, Hartree-Fock functions and Hylleraas-type wave functions with up to 84 parameters. It is found that values of the matrix elements of the parity-violating interaction can differ considerably from the values obtained from the good wave functions, even when these simple wave functions give accurate values for the matrix elements in question

Hiller, J.; Sucher, J.; Bhatia, A. K.; Feinberg, G.

1980-01-01

212

Reappraisal of the Electric Dipole Moment Enhancement Factor for Thallium

NASA Astrophysics Data System (ADS)

The electric dipole moment (EDM) enhancement factor of atomic Tl is of considerable interest as it has been used in determining the most accurate limit on the electron EDM to date. However, its value varies from -179 to -1041 in different approximations. In view of the large uncertainties associated with many of these calculations, we perform an accurate calculation employing the relativistic coupled-cluster theory and obtain -466, which in combination with the most accurate measurement of Tl EDM [Phys. Rev. Lett. 88, 071805 (2002)PRLTAO0031-900710.1103/PhysRevLett.88.071805] yields a new limit for the electron EDM: |de|<2.0×10-27ecm.

Nataraj, H. S.; Sahoo, B. K.; Das, B. P.; Mukherjee, D.

2011-05-01

213

Reappraisal of the electric dipole moment enhancement factor for thallium.

The electric dipole moment (EDM) enhancement factor of atomic Tl is of considerable interest as it has been used in determining the most accurate limit on the electron EDM to date. However, its value varies from -179 to -1041 in different approximations. In view of the large uncertainties associated with many of these calculations, we perform an accurate calculation employing the relativistic coupled-cluster theory and obtain -466, which in combination with the most accurate measurement of Tl EDM [Phys. Rev. Lett. 88, 071805 (2002)] yields a new limit for the electron EDM: |d(e)| < 2.0 × 10?²?e cm. PMID:21668210

Nataraj, H S; Sahoo, B K; Das, B P; Mukherjee, D

2011-05-20

214

Parity Violation and Electric Dipole Moments in Atoms and Molecules

NASA Astrophysics Data System (ADS)

We review the current status of the study of parity and time invariance violation in atoms, nuclei and molecules. We focus on parity nonconservation (PNC) in cesium (CS) and three of the most promising areas of research: (i) PNC in a chain of isotopes, (ii) search for nuclear anapole moments, and (iii) search for permanent electric dipole moments (EDMs) of atoms and molecules, which in turn are caused by either an electron EDM or nuclear T, P-odd moments such as a nuclear EDM or nuclear Schiff moment.

Dzuba, V. A.; Flambaum, V. V.

2012-11-01

215

Intrinsic Electric Dipole Moments of Paramagnetic Atoms: Rubidium and Cesium

The electric dipole moment (EDM) of paramagnetic atoms is sensitive to the\\u000aintrinsic EDM contribution from that of its constituent electrons and a\\u000ascalar--pseudo-scalar (S-PS) electron-nucleus interactions. The electron EDM\\u000aand the S-PS EDM contribution to atomic EDM scales as Z^3. Thus, the heavy\\u000aparamagnetic atomic systems will exhibit large enhancement factors. However,\\u000athe nature of the coupling is so

H. S. Nataraj; B. K. Sahoo; B. P. Das; D. Mukherjee

2008-01-01

216

Reappraisal of the Electric Dipole Moment Enhancement Factor for Thallium

The electric dipole moment (EDM) enhancement factor of atomic Tl is of considerable interest as it has been used in determining the most accurate limit on the electron EDM to date. However, its value varies from -179 to -1041 in different approximations. In view of the large uncertainties associated with many of these calculations, we perform an accurate calculation employing the relativistic coupled-cluster theory and obtain -466, which in combination with the most accurate measurement of Tl EDM [Phys. Rev. Lett. 88, 071805 (2002)] yields a new limit for the electron EDM: |d{sub e}|<2.0x10{sup -27}e cm.

Nataraj, H. S. [Cyclotron and Radioisotope Center, Tohoku University, Sendai 9808578 (Japan); Sahoo, B. K. [Theoretical Physics Division, Physical Research Laboratory, Ahmedabad 380009 (India); Das, B. P. [Theoretical Astrophysics Group, Indian Institute of Astrophysics, Bangalore 560034 (India); Mukherjee, D. [Indian Association for the Cultivation of Sciences, Kolkata 700032 (India)

2011-05-20

217

The permanent electric dipole moment of chromium monoxide

NASA Technical Reports Server (NTRS)

The permanent electric dipole moments for the X 5Pi and B 5pi states of gas-phase CrO have been experimentally determined using the sub-Doppler optical technique of intermodulated fluorescence spectroscopy in conjunction with the Stark effect. The measured values are 3.88 + or - 0.13 and 4.1 + or - 1.8 D for the X and B states, respectively. The theoretical values determined for the X state using multireference CI iterative-natural-orbital and finite-field calculations are in excellent agreement with the experimental value.

Steimle, Timothy C.; Nachman, David F.; Shirley, Jeffrey E.; Bauschlicher, Charles W.; Langhoff, Stephen R.

1989-01-01

218

Measurement of the neutron electric dipole moment by crystal diffraction

An experiment using a prototype setup to search for the neutron electric dipole moment by measuring spin-rotation in a non-centrosymmetric crystal (quartz) was carried out to investigate statistical sensitivity and systematic effects of the method. It has been demonstrated that the concept of the method works. The preliminary result of the experiment is $d_{\\rm n}=(2.5\\pm 6.5)\\cdot 10^{-24}$ e$\\cdot $cm. The experiment showed that an accuracy of $\\sim 2.5\\cdot 10^{-26}$ e$\\cdot $cm can be obtained in 100 days data taking, using available quartz crystals and neutron beams.

V. V. Fedorov; M. Jentschel; I. A. Kuznetsov; E. G. Lapin; E. Lelievre-Berna; V. Nesvizhevsky; A. Petoukhov; S. Yu. Semenikhin; T. Soldner; F. Tasset; V. V. Voronin; Yu. P. Braginetz

2009-07-09

219

T violation in radiative $?$ decay and electric dipole moments

In radiative $\\beta$ decay, $T$ violation can be studied through a spin-independent $T$-odd correlation. We consider contributions to this correlation by beyond the standard model (BSM) sources of $T$-violation, arising above the electroweak scale. At the same time such sources, parametrized by dimension-6 operators, can induce electric dipole moments (EDMs). As a consequence, the manifestations of the $T$-odd BSM physics in radiative $\\beta$ decay and EDMs are not independent. Here we exploit this connection to show that current EDM bounds already strongly constrain the spin-independent $T$-odd correlation in radiative $\\beta$ decay.

W. G. Dekens; K. K. Vos

2015-02-16

220

Restrictions on the neutrino magnetic dipole moment

We examine mechanisms for producing neutrino magnetic moments from a wide class of particle theories which are extensions of the standard model. We show that it is difficult to naturally obtain a moment greater than ~ 10-2 electron Bohr magnetons. Thus models of phenomena requiring moments of order ~ 10-10 magnetons, such as those proposed as a resolution to the

M. J. Duncan; J. A. Grifols; A. Mendez; S. Uma Sankar

1987-01-01

221

Demonstration Cold Atom Fountain Electron Electric Dipole Moment (EDM) Experiment

A demonstration cold-atom-fountain electron EDM experiment has been operated at LBNL. The apparatus is free of static magnetic fields (B < 1 nT) which reduces sensitivity to motional magnetic field effects. Electric-field quantization, state preparation and detection in field-free regions, fractional-cycle pulses, active motional magnetic field nulling, multiple-quantum transitions, and web based, unattended operation of the experiment will be discussed.

Harvey Gould; Jason M. Amini; Charles T. Munger

2006-01-01

222

LABORATORY VI ELECTRICITY FROM MAGNETISM

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

Minnesota, University of

223

NASA Astrophysics Data System (ADS)

In quantum information processing, one of the most useful interactions between qubits is the Ising type interaction. We propose a scheme to implement the exact Ising interaction through magnetic dipoledipole interaction. Although magnetic dipolar interaction is Heisenberg type in general, this interaction can bring about the exact mathematical form of the Ising interaction if qubit levels are chosen among the highest magnetic quantum number states. Real physical systems to which our scheme can be applied include rotational states of molecules, hyperfine states of atoms, or electronic states of nitrogen-vacancy centers in diamond. We analyze the feasibility of our scheme for these systems. For example, when the hyperfine levels of rubidium 87 atoms are chosen as qubits and the distance of the two atoms is 0.1 micrometer, the controlled-Z gate time will be 8.5 ms. We suggest diverse search and study to achieve optimal implementation of this scheme.

Yun, Sang Jae; Kim, Jaewan; Nam, Chang Hee

2015-04-01

224

Performance of dipole magnets in helium II

Data from tests in He II of four 1-meter-long magnets are presented. The maximum quench current is increased up to 30 percent, compared with tests in He I. Data from calorimetric measurements of heat generated during cyclic operation are presented. Quenches were induced by heaters placed near the conductor, and the energy required to induce quenches in He II and in He I are compared.

Althaus, R.; Caspi, S.; Gilbert, W.S.; Hassenzahl, W.; Meuser, R.; Rechen, J.; Taylor, C.; Warren, R.

1981-03-01

225

A superconducting dipole magnet for laser spectroscopy

. . . . . . . . . C. Estimated Heat Input by Conduction. . . . . . D. Summary of Estimated Heat Input. . . . . . . . . . V PERFORMANCE OF THE CRYOSTAT. . . . . . . . ? A, Cryogen Consumption During Cooling. . . . . . . . . B. Cryogen Consumption During Operation..., the magnet is located off-center on the bottom arc of the cylinder, remaining submerged in coolant for as long as possible. This orientation pmvides structural stability, but puts the bore tube only two inches from the base of the vessel. A cryogenic...

Wagenhauser, Kenneth Edward

1990-01-01

226

Electricity and Magnetism (1135-1225 Monday, Wednesday, Rutherford 115)

, basic notions, Guass's law, electric fields and potentials, work and energy, image methods, dipolesElectricity and Magnetism PHYS-242: (1135-1225 Monday, Wednesday, Rutherford 115) Course site: http: lovejoy@physics.mcgill.ca Teaching assistants: Sebastien Prince, email, room !! Benoit, Lefebvre, email

Lovejoy, Shaun

227

Optical extinction enhancement at infrared range in a single graphene sheet by patterning split ring resonators (SRRs) is studied. It is found that electric dipole mode is stronger in enhancing infrared extinction compared with magnetic mode and higher order modes. We suggest to improve infrared extinction of the SRR graphene sheet by increasing the graphene area ratio to the unit cell, and with the increase of the graphene area ratio radiation ability of the electric dipole mode and dissipation of graphene will competing for a maximum infrared absorption of about 50%. The findings on enhancing infrared extinction of graphene sheet by harvesting the electric dipole mode may have potential applications in terahertz and infrared detection and modulation for graphene photonics and optoelectronics.

Fan, Yuancheng; Zhang, Zhengren; Li, Hongqiang

2013-01-01

228

NASA Astrophysics Data System (ADS)

The multiconfiguration Dirac-Hartree-Fock method is employed to calculate atomic electric dipole moments in the ground states of Ra225, Hg199, and Yb171. For the calculations of the matrix elements we extend the relativistic atomic structure package grasp2k. The extension includes programs to evaluate matrix elements of PT-odd electron-nucleus tensor-pseudotensor and pseudoscalar-scalar interactions, the atomic electric dipole operator, the nuclear Schiff moment, and the interaction of the electron electric dipole moment with nuclear magnetic moments. The interelectronic interactions are accounted for through valence and core-valence electron correlation effects. The electron shell relaxation is included with separately optimized wave functions of opposite parities.

RadiĊĞtÄ--, Laima; Gaigalas, Gediminas; Jönsson, Per; Biero?, Jacek

2014-07-01

229

The multiconfiguration Dirac-Hartree-Fock (MCDHF) method has been employed to calculate atomic electric dipole moments (EDM) of 225^Ra, 199^Hg, and 171^Yb. For the calculations of the matrix elements we extended the relativistic atomic structure package GRASP2K. The extension includes programs to evaluate matrix elements of (P, T)-odd e-N tensor-pseudotensor and pseudoscalar-scalar interactions, the atomic electric dipole interaction, the nuclear Schiff moment, and the interaction of the electron electric dipole moment with nuclear magnetic moments. The interelectronic interactions were accounted for through valence and core-valence electron correlation effects. The electron shell relaxation was included with separately optimised wave functions of opposite parities.

Laima Radziute; Gediminas Gaigalas; Per Jonsson; Jacek Biero

2013-12-23

230

The multiconfiguration Dirac-Hartree-Fock (MCDHF) method has been employed to calculate atomic electric dipole moments (EDM) of 225^Ra, 199^Hg, and 171^Yb. For the calculations of the matrix elements we extended the relativistic atomic structure package GRASP2K. The extension includes programs to evaluate matrix elements of (P, T)-odd e-N tensor-pseudotensor and pseudoscalar-scalar interactions, the atomic electric dipole interaction, the nuclear Schiff moment, and the interaction of the electron electric dipole moment with nuclear magnetic moments. The interelectronic interactions were accounted for through valence and core-valence electron correlation effects. The electron shell relaxation was included with separately optimised wave functions of opposite parities.

Radziute, Laima; Jonsson, Per; Biero, Jacek

2013-01-01

231

Measuring molecular electric dipoles using trapped atomic ions and ultrafast laser pulses

We study a hybrid quantum system composed of an ion and an electric dipole. We show how a trapped ion can be used to measure the small electric field generated by a classical dipole. We discuss the application of this scheme to measure the electric dipole moment of cold polar molecules, whose internal state can be controlled with ultrafast laser pulses, by trapping them in the vicinity of a trapped ion.

Jordi Mur-Petit; Juan José García-Ripoll

2015-01-12

232

Measuring molecular electric dipoles using trapped atomic ions and ultrafast laser pulses

NASA Astrophysics Data System (ADS)

We study a hybrid quantum system composed of an ion and an electric dipole. We show how a trapped ion can be used to measure the small electric field generated by a classical dipole. We discuss the application of this scheme to measure the electric dipole moment of cold polar molecules, whose internal state can be controlled with ultrafast laser pulses, by trapping them in the vicinity of a trapped ion.

Mur-Petit, Jordi; García-Ripoll, Juan José

2015-01-01

233

Model of Dipole Field Variations in the LEP Bending Magnets

The determination of the Z mass at LEP requires a knowledge of the relative beam energy in the order of 10 ppm, therefore it is essential to understand the dipole field variations to the same level of accuracy. In LEP the bending magnet field shows a relative increase of the order of 100 ppm over 10 hours, which was found to be caused by leakage currents from railways flowing along the vacuum cham ber and temperature variations. A LEP dipole test bench was set up for systematic investigations. Field variations were monitored with NMR probes while the cooling water temperature of both coil and vacuum chamber was kept under control. The results lead to a parametrisation of the magnetic field variation as a function of the vacuum chamber current and temperature.

Bravin, Enrico; Drees, A; Mugnai, G

1998-01-01

234

Dipole corrector magnets for the LBNE beam line

The conceptual design of a new dipole corrector magnet has been thoroughly studied. The planned Long-Baseline Neutrino Experiment (LBNE) beam line will require correctors capable of greater range and linearity than existing correctors, so a new design is proposed based on the horizontal trim dipole correctors built for the Main Injector synchrotron at Fermilab. The gap, pole shape, length, and number of conductor turns remain the same. To allow operation over a wider range of excitations without overheating, the conductor size is increased, and to maintain better linearity, the back leg thickness is increased. The magnetic simulation was done using ANSYS to optimize the shape and the size of the yoke. The thermal performance was also modeled and analyzed.

Yu, M.; Velev, G.; Harding, D.; /Fermilab

2011-03-01

235

Visualizing Special Relativity: The Field of An Electric Dipole Moving at Relativistic Speed

ERIC Educational Resources Information Center

The electromagnetic field is determined for a time-varying electric dipole moving with a constant velocity that is parallel to its moment. Graphics are used to visualize this field in the rest frame of the dipole and in the laboratory frame when the dipole is moving at relativistic speed. Various phenomena from special relativity are clearly

Smith, Glenn S.

2011-01-01

236

Electric dipole polarizabilities of hydrogen and helium isotopes

The electric dipole polarizabilities of {sup 3}H, {sup 3}He, and {sup 4}He are calculated directly using the Schroedinger equation with the latest generation of two- and three-nucleon interactions. These quantities are necessary in order to obtain accurate nuclear-polarization corrections for transitions involving S-waves in one-and two-electron atoms. Our results are compared to previous results, and it is shown that direct calculations of the electric polarizability of {sup 4}He using modern nuclear potentials are smaller than published values calculated using experimental photoabsorption data. The status of this topic is assessed in the context of precise measurements of transitions in one- and two-electron atoms.

Stetcu, I [Los Alamos National Laboratory; Friar, J [Los Alamos National Laboratory; Hayes, A C [Los Alamos National Laboratory; Quaglioni, S [LLNL

2009-01-01

237

Electric Dipole Polarizabilities of Hydrogen and Helium Isotopes

The electric dipole polarizabilities of $^3$H, $^3$He, and $^4$He are calculated directly using the Schr\\"odinger equation with the latest generation of two- and three-nucleon interactions. These polarizabilities are necessary in order to obtain accurate nuclear-polarization corrections for transitions involving S-waves in one- and two-electron atoms. Our results are compared to previous results, and it is shown that direct calculations of the electric polarizability of $^4$He using modern nuclear potentials are smaller than published values calculated using experimental photoabsorption data. The status of this topic is assessed in the context of precise measurements of transitions in one- and two-electron atoms.

I. Stetcu; S. Quaglioni; J. L. Friar; A. C. Hayes; P. Navrátil

2009-04-23

238

NASA Astrophysics Data System (ADS)

Magnetic nanoparticles (MNPs) are used as therapeutic and diagnostic tools, such as for treating hyperthermia and in magnetic particle imaging, respectively. Magnetic relaxation is one of the heating mechanisms of MNPs. Brownian and Néel relaxation times are calculated conventional theories; however, the influence of dipole-dipole interactions has not been considered in conventional models. In this study, water-dispersed MNPs of different concentrations and MNPs fixed with an epoxy bond were prepared. dc and ac hysteresis loops for each sample were measured. With respect to both dc and ac hysteresis loops, magnetization decreased with the increase in MNP concentration because of inhibition of magnetic moment rotation due to dipole-dipole interactions. Moreover, intrinsic loss power (ILP) was estimated from the areas of the ac hysteresis loops. The dependence of ILP on the frequency of the magnetic field was evaluated for each MNP concentration. The peak frequency of ILP increased with the decrease in MNP concentration. These peaks were due to Brownian relaxation, as they were not seen with the fixed sample. This indicates that the Brownian relaxation time became shorter with lower MNP concentration, because the weaker dipole-dipole interactions with lower concentrations suggested that the magnetic moments could rotate more freely.

Ota, Satoshi; Yamada, Tsutomu; Takemura, Yasushi

2015-05-01

239

Strong dependence of ultracold chemical rates on electric dipole moments

We use the quantum threshold laws combined with a classical capture model to provide an analytical estimate of the chemical quenching cross sections and rate coefficients of two colliding particles at ultralow temperatures. We apply this quantum threshold model (QT model) to indistinguishable fermionic polar molecules in an electric field. At ultracold temperatures and in weak electric fields, the cross sections and rate coefficients depend only weakly on the electric dipole moment d induced by the electric field. In stronger electric fields, the quenching processes scale as d{sup 4(L+(1/2))} where L>0 is the orbital angular-momentum quantum number between the two colliding particles. For p-wave collisions (L=1) of indistinguishable fermionic polar molecules at ultracold temperatures, the quenching rate thus scales as d{sup 6}. We also apply this model to pure two-dimensional collisions and find that chemical rates vanish as d{sup -4} for ultracold indistinguishable fermions. This model provides a quick and intuitive way to estimate chemical rate coefficients of reactions occuring with high probability.

Quemener, Goulven; Bohn, John L. [JILA, University of Colorado, Boulder, Colorado 80309-0440 (United States)

2010-02-15

240

General magnetic transition dipole moments for electron paramagnetic resonance.

We present general expressions for the magnetic transition rates in electron paramagnetic resonance (EPR) experiments of anisotropic spin systems in the solid state. The expressions apply to general spin centers and arbitrary excitation geometry (Voigt, Faraday, and intermediate). They work for linear and circular polarized as well as unpolarized excitation, and for crystals and powders. The expressions are based on the concept of the (complex) magnetic transition dipole moment vector. Using the new theory, we determine the parities of ground and excited spin states of high-spin (S=5/2) Fe(III) in hemin from the polarization dependence of experimental EPR line intensities. PMID:25615456

Nehrkorn, Joscha; Schnegg, Alexander; Holldack, Karsten; Stoll, Stefan

2015-01-01

241

Electric and magnetic response to the continuum for A=7 isobars in a dicluster model

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.

A. Mason; R. Chatterjee; L. Fortunato; A. Vitturi

2008-11-11

242

Thermal equilibrium of non-neutral plasma in dipole magnetic field

In a homogeneous magnetic field, a non-neutral plasma creates a "thermal equilibrium" on a rigidly rotating frame; canceling the self electric field by the Lorentz-transformed electric filed, the Boltzmann distribution yields a homogeneous density profile inside the confinement region. Here, we extend the notion of thermal equilibrium to a dipole magnetic field. The scale hierarchy of adiabatic invariants, i.e., the magnetic moment $\\mu$, the action $J_\\parallel$ of bounce motion, and the action $\\psi$ of the toroidal rotation, guides us to elucidate how the plasma relaxes the free energy. The distribution function with no $\\psi$ dependence is shown to be the "thermal equilibrium", which turns out to be a rigidly rotating clump of particles (just same as in a homogeneous magnetic field), while the density is no longer homogeneous in a dipole magnetic field. This theoretical model explains the experimental observation [Z. Yoshida \\textit{et al.}, Phys. Rev. Lett. \\textbf{104} (2010), 235004], and will be usefu...

Sato, Naoki; Yoshida, Zensho

2015-01-01

243

Magnetic dipole moment of the $?(1232)$ in chiral perturbation theory

The magnetic dipole moment of the $\\Delta (1232)$ is calculated in the framework of manifestly Lorentz-invariant baryon chiral perturbation theory in combination with the extended on-mass-shell renormalization scheme. As in the case of the nucleon, at leading order both isoscalar and isovector anomalous magnetic moments are given in terms of two low-energy constants. In contrast to the nucleon case, at next-to-leading order the isoscalar anomalous magnetic moment receives a (real) loop contribution. Moreover, due to the unstable nature of the $\\Delta (1232)$, at next-to-leading order the isovector anomalous magnetic moment not only receives a real but also an imaginary loop contribution.

C. Hacker; N. Wies; J. Gegelia; S. Scherer

2006-03-31

244

Proposal for a sensitive search for electric dipole moment of electron with matrix-isolated radicals

We propose using matrix-isolated paramagnetic diatomic molecules to search for the electric dipole moment of electron (eEDM). As was suggested by Shapiro in 1968, the eEDM leads to a magnetization of a sample in the external electric field. In a typical condensed matter experiment, the effective field on the unpaired electron is of the same order of magnitude as the laboratory field, typically about $10^{5}$V/cm. We exploit the fact that the effective electric field inside heavy polar molecules is in the order of $10^{10}$V/cm. This leads to a huge enhancement of the Shapiro effect. Statistical sensitivity of the proposed experiment may allow one to improve the current limit on eEDM by three orders of magnitude in few hours accumulation time.

M. G. Kozlov; Andrei Derevianko

2006-07-31

245

Hadronic electric dipole moments in R-parity violating supersymmetry

We calculate the electric dipole moments (EDM) of the neutral {sup 199}Hg atom, neutron and deuteron within a generic R-parity violating SUSY model (Re{sub p} SUSY) on the basis of a one-pion-exchange model with CP-odd pion-nucleon interactions. We consider two types of the Re{sub p} SUSY contributions to the above hadronic EDMs: via the quark chromoelectric dipole moments (CEDM) and CP-violating 4-quark interactions. We demonstrate that the former contributes to all the three studied EDMs while the latter appears only in the nuclear EDMs via the CP-odd nuclear forces. We find that the Re{sub p} SUSY induced 4-quark interactions arise at tree level through the sneutrino exchange and involve only s and b quarks. Therefore, their effect in hadronic EDMs is determined by the strange and bottom-quark sea of the nucleon. From the null experimental results on the hadronic EDMs we derive the limits on the imaginary parts of certain products Im({lambda}{sup '}{lambda}{sup '}*) of the trilinear Re{sub p}-couplings and show that the currently best limits come from the {sup 199}Hg EDM experiments. We demonstrate that some of these limits are better than those existing in the literature. We argue that future storage ring experiments on the deuteron EDM are able to improve these limits by several orders of magnitude.

Faessler, Amand; Gutsche, Thomas; Lyubovitskij, Valery E. [Institut fuer Theoretische Physik, Universitaet Tuebingen, Auf der Morgenstelle 14, D-72076 Tuebingen (Germany); Kovalenko, Sergey [Departamento de Fisica, Universidad Tecnica Federico Santa Maria, Casilla 110-V, Valparaiso (Chile)

2006-06-01

246

Laser trapping of radium for an electric dipole moment measurement

NASA Astrophysics Data System (ADS)

The best limits on time-reversal violation in the nuclear sector are currently set through electric dipole moment (EDM) searches on the neutron and Hg-199. Recent theoretical calculations predict that atomic EDM measurements of certain octupole-deformed nuclei, e.g., in the radium isotopic chain, are two to three orders of magnitude more sensitive to the underlying time-reversal violation than the one in Hg-199. Ra-225, with nuclear spin 1/2 and a radioactive half-life of 15 days, is a particularly attractive candidate for a tabletop EDM measurement based on a laser-cooling and trapping approach. Towards this end, we have successfully cooled and trapped atoms of Ra-225 and Ra-226 in a magneto-optical trap -- a first for this rare element -- and have identified black-body radiation as a beneficial source of optical repumping. We will present our laser cooling scheme and ongoing measurements of atomic level energies, lifetimes, isotope shifts and hyperfine structure in radium and discuss our progress towards an EDM measurement of Ra-225 based on an optical dipole trap. This work is supported by DOE, Office of Nuclear Physics, under contract No. DE-AC02-06CH11357.

Mueller, P.; Sulai, I. A.; Trimble, W.; Ahmad, I.; Bailey, K.; Bishof, M.; Greene, J. P.; Guest, J. R.; Holt, R. J.; Lu, Z.-T.; O'Connor, T. P.; Gould, H. A.

2008-05-01

247

Heavy polar molecules can be used to measure the electric dipole moment of\\u000athe electron, which is a sensitive probe of physics beyond the Standard Model.\\u000aThe value is determined by measuring the precession of the molecule's spin in a\\u000aplane perpendicular to an applied electric field. The longer this precession\\u000aevolves coherently, the higher the precision of the measurement.

M. R. Tarbutt; J. J. Hudson; B. E. Sauer; E. A. Hinds

2009-01-01

248

Space propulsion by fusion in a magnetic dipole

A conceptual design is discussed for a fusion rocket propulsion system based on the magnetic dipole configuration. The dipole is found to have features well suited to space applications. Example parameters are presented for a system producing a specific power of 1 kW/kg, capable of interplanetary flights to Mars in 90 days and to Jupiter in a year, and of extra-solar-system flights to 1000 astronomical units (the Tau mission) in 20 years. This is about 10 times better specific power toward 10 kW/kg are discussed, as in an approach to implementing the concept through proof-testing on the moon. 21 refs., 14 figs., 2 tabs.

Teller, E.; Glass, A.J.; Fowler, T.K. (Lawrence Livermore National Lab., CA (USA)); Hasegawa, A. (AT and T Bell Labs., Murray Hill, NJ (USA)); Santarius, J.F. (Wisconsin Univ., Madison, WI (USA). Fusion Technology Inst.)

1991-04-12

249

Electric dipole moment constraints on minimal electroweak baryogenesis

We study the simplest generic extension of the standard model which allows for conventional electroweak baryogenesis, through the addition of dimension-six operators in the Higgs sector. At least one such operator is required to be CP-odd, and we study the constraints on such a minimal setup, and related scenarios with minimal flavor violation, from the null results of searches for electric dipole moments (EDMs), utilizing the full set of two-loop contributions to the EDMs. The results indicate that the current bounds are stringent, particularly that of the recently updated neutron EDM, but fall short of ruling out these scenarios. The next generation of EDM experiments should be sufficiently sensitive to provide a conclusive test.

Huber, Stephan J. [Theoretical Division, Department of Physics, CERN, Geneva 23, CH-1211 (Switzerland); Pospelov, Maxim [Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 (Canada); Ritz, Adam [Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 5C2 (Canada)

2007-02-01

250

Electric-dipole sum rule in nuclear matter

NASA Astrophysics Data System (ADS)

The enhancement factor K in the electric-dipole sum rule for some realistic models of symmetrical nuclear matter is calculated using variational theory. The nuclear-matter wave function used contains central, spin, isospin, tensor and spin-orbit pair correlations. The non-central correlations, particularly the tensor one, give the major contribution to K. At experimental equilibrium density K. turns out to be ? 1.8, of which 65% comes from OPEP and 30% from the short-range part of the interaction. The two-pion-exchange three-nucleon interaction contributes ? 0.2% and is cancelled, to a large extent, by the contribution due to the intermediate-range two-body potential. The relationship of the summed oscillator strength with the effective mass is also discussed.

Fabrocini, A.; Fantoni, S.

1985-03-01

251

Low-energy electric dipole response in 120Sn

The electric dipole strength in 120Sn has been extracted from proton inelastic scattering experiments at E_p = 295 MeV and at forward angles including 0 degree. Below neutron threshoild it differs from the results of a 120Sn(gamma,gamma') experiment and peaks at an excitation energy of 8.3 MeV. The total strength corresponds to 2.3(2)% of the energy-weighted sum rule and is more than three times larger than what is observed with the (gamma,gamma') reaction. This implies a strong fragmentation of the E1 strength and/or small ground state branching ratios of the excited 1- states.

A. M. Krumbholz; P. von Neumann-Cosel; T. Hashimoto; A. Tamii; T. Adachi; C. A. Bertulani; H. Fujita; Y. Fujita; E. Ganioglu; K. Hatanaka; C. Iwamoto; T. Kawabata; N. T. Khai; A. Krugmann; D. Martin; H. Matsubara; R. Neveling; H. Okamura; H. J. Ong; I. Poltoratska; V. Yu. Ponomarev; A. Richter; H. Sakaguchi; Y. Shimbara; Y. Shimizu; J. Simonis; F. D. Smit; G. Susoy; J. H. Thies; T. Suzuki; M. Yosoi; J. Zenihiro

2015-03-04

252

Low-energy electric dipole response in 120Sn

Electric dipole strength in 120Sn below the neutron threshold has been extracted from proton inelastic scattering experiments at E_p = 295 MeV and at forward angles including 0 degree. The strength distribution is very different from the results of a 120Sn(gamma,gamma') experiment and peaks at an excitation energy of 8.3 MeV. The total strength corresponds to 2.3(2)% of the energy-weighted sum rule and is more than three times larger than what is observed with the (gamma,gamma') reaction. This implies a strong fragmentation of the E1 strength and/or small ground state branching ratios of the excited 1- states.

Krumbholz, A M; Hashimoto, T; Tamii, A; Adachi, T; Bertulani, C A; Fujita, H; Fujita, Y; Ganioglu, E; Hatanaka, K; Iwamoto, C; Kawabata, T; Khai, N T; Krugmann, A; Martin, D; Matsubara, H; Neveling, R; Okamura, H; Ong, H J; Poltoratska, I; Ponomarev, V Yu; Richter, A; Sakaguchi, H; Shimbara, Y; Shimizu, Y; Simonis, J; Smit, F D; Susoy, G; Thies, J H; Suzuki, T; Yosoi, M; Zenihiro, J

2015-01-01

253

Thermal annealing-induced electric dipole relaxation in natural alexandrite

NASA Astrophysics Data System (ADS)

Electrical properties of natural alexandrite (BeAl2O4:Cr3+) are investigated by the thermally stimulated depolarization current (TSDC) technique. Samples are submitted to consecutive annealing processes and TSDC is carried out after each annealing, yielding bands with different parameters. These bands are fitted by a continuous distribution of relaxation parameters: activation energy and pre-exponential factor of the Arrhenius equation. It has been observed that annealing influences the dipole relaxation behavior, since it promotes a modification of Fe3+ and Cr3+ impurity distributions on sites of distinct symmetry: Al1 and Al2. In order to have a reference for comparison, TSDC is also carried out on a synthetic alexandrite sample, where the only impurity present is Cr3+ ion.

Scalvi, Rosa M. Fernandes; Li, Maximo Siu; Scalvi, Luis V. A.

2005-02-01

254

CKM benchmarks for electron electric dipole moment experiments

NASA Astrophysics Data System (ADS)

All current experiments searching for an electron electric dipole moment (EDM) de are performed with atoms and diatomic molecules. Motivated by significant recent progress in searches for an EDM-type signal in diatomic molecules with an uncompensated electron spin, we provide an estimate for the expected signal in the Standard Model due to the Cabibbo-Kobayashi-Maskawa (CKM) phase. We find that the main contribution originates from the effective electron-nucleon operator eŻi?5eNŻN, induced by a combination of weak and electromagnetic interactions at O(GF2?2), and not by the CKM-induced electron EDM itself. When the resulting atomic P ,T-odd mixing is interpreted as an equivalent electron EDM, this estimate leads to the benchmark deequiv(CKM)10-38 ecm.

Pospelov, Maxim; Ritz, Adam

2014-03-01

255

CP violation in beta decay and electric dipole moments

NASA Astrophysics Data System (ADS)

The T-odd correlation coefficient D in nuclear ? decay probes CP violation in many theories beyond the standard model. We provide an analysis for how large D can be in light of constraints from electric dipole moment (EDM) searches. We argue that the neutron EDM dn currently provides the strongest constraint on D, which is 10-103 times stronger than current direct limits on D (depending on the model). In particular, contributions to D in leptoquark models (previously regarded as EDM safe) are more constrained than previously thought. Bounds on D can be weakened only by fine-tuned cancellations or if theoretical uncertainties are larger than estimated in dn. We also study implications for D from mercury and deuteron EDMs.

Ng, John; Tulin, Sean

2012-02-01

256

Electroweak baryogenesis, electric dipole moments, and Higgs diphoton decays

NASA Astrophysics Data System (ADS)

We study the viability of electroweak baryogenesis in a two Higgs doublet model scenario augmented by vector-like, electroweakly interacting fermions. Considering a limited, but illustrative region of the model parameter space, we obtain the observed cosmic baryon asymmetry while satisfying present constraints from the non-observation of the permanent electric dipole moment (EDM) of the electron and the combined ATLAS and CMS result for the Higgs boson diphoton decay rate. The observation of a non-zero electron EDM in a next generation experiment and/or the observation of an excess (over the Standard Model) of Higgs to diphoton events with the 14 TeV LHC run or a future e + e - collider would be consistent with generation of the observed baryon asymmetry in this scenario.

Chao, Wei; Ramsey-Musolf, Michael J.

2014-10-01

257

Intrinsic electric dipole moments of paramagnetic atoms: rubidium and cesium.

The electric dipole moment (EDM) of paramagnetic atoms is sensitive to the intrinsic EDM contribution from that of its constituent electrons and a scalar-pseudoscalar (S-PS) electron-nucleus interaction. The electron EDM and the S-PS contributions to the EDMs of these atoms scale as approximately Z;{3}. Thus, the heavy paramagnetic atoms will exhibit large EDM enhancement factors. However, the sizes of the couplings are so small that they are of interest of high precision atomic experiments. In this work we have computed the EDM enhancement factors of the ground states of Rb and Cs due to both the electron EDM and the S-PS EDM using the relativistic coupled-cluster theory. The importance of determining precise ab initio enhancement factors and experimental results of atomic EDMs in deducing a reliable limit on the electron EDM is emphasized. PMID:18764250

Nataraj, H S; Sahoo, B K; Das, B P; Mukherjee, D

2008-07-18

258

Intrinsic Electric Dipole Moments of Paramagnetic Atoms: Rubidium and Cesium

The electric dipole moment (EDM) of paramagnetic atoms is sensitive to the intrinsic EDM contribution from that of its constituent electrons and a scalar--pseudo-scalar (S-PS) electron-nucleus interactions. The electron EDM and the S-PS EDM contribution to atomic EDM scales as Z^3. Thus, the heavy paramagnetic atomic systems will exhibit large enhancement factors. However, the nature of the coupling is so small that it becomes an interest of high precision atomic experiments. In this work, we have computed the EDM enhancement factors of the ground states of Rb and Cs due to both the electron EDM and the S-PS EDM using the relativistic coupled-cluster (RCC) theory. The importance of obtaining the precise enhancement factors and the experimental results in deducing a reliable limit on the electron EDM is emphasized.

H. S. Nataraj; B. K. Sahoo; B. P. Das; D. Mukherjee

2008-04-07

259

Electroweak Baryogenesis, Electric Dipole Moments, and Higgs Diphoton Decays

We study the viability of electroweak baryogenesis in a two Higgs doublet model scenario augmented by vector-like, electroweakly interacting fermions. Considering a limited, but illustrative region of the model parameter space, we obtain the observed cosmic baryon asymmetry while satisfying present constraints from the non-observation of the permanent electric dipole moment (EDM) of the electron and the combined ATLAS and CMS result for the Higgs boson diphoton decay rate. The observation of a non-zero electron EDM in a next generation experiment and/or the observation of an excess (over the Standard Model) of Higgs to diphoton events with the 14 TeV LHC run or a future $e^+e^-$ collider would be consistent with generation of the observed baryon asymmetry in this scenario.

Wei Chao; Michael J. Ramsey-Musolf

2014-06-02

260

Nuclear Electric Dipole Moments in Chiral Effective Field Theory

We provide the first consistent and complete calculation of the electric dipole moments of the deuteron, helion, and triton in the framework of chiral effective field theory. The CP-conserving and CP-violating interactions are treated on equal footing and we consider CP-violating one-, two-, and three-nucleon operators up to next-to-leading-order in the chiral power counting. In particular, we calculate for the first time EDM contributions induced by the CP-violating three-pion operator. We find that effects of CP-violating nucleon-nucleon contact interactions are larger than those found in previous studies based on phenomenological models for the CP-conserving nucleon-nucleon interactions. Our results are model-independent and can be used to test various scenarios of CP violation. As examples, we study the implications of our results on the QCD $\\theta$-term and the minimal left-right symmetric model.

J. Bsaisou; J. de Vries; C. Hanhart; S. Liebig; Ulf-G. Meißner; D. Minossi; A. Nogga; A. Wirzba

2014-11-21

261

MCDHF calculations of the electric dipole moment of radium induced by the nuclear Schiff moment

MCDHF calculations of the electric dipole moment of radium induced by the nuclear Schiff moment the electric dipole moment of the 7s6d 3 D2 state of radium induced by the nuclear Schiff moment. The results investigated in laser traps for their prospectives to perform EDM experi- ments. Presently, radium appears

Paris-Sud XI, Universitİ de

262

Fabrication and test results of a high field, Nb3Sn superconducting racetrack dipole magnet

The LBNL Superconducting Magnet Program is extending accelerator magnet technology to the highest possible fields. A 1 meter long, racetrack dipole magnet, utilizing state-of-the-art Nb3Sn superconductor, has been built and tested. A record dipole filed of 14.7 Tesla has been achieved. Relevant features of the final assembly and test results are discussed

R. Benjegerdes; P. Bish; D. Byford; S. Caspi; D. R. Dietderich; S. A. Gourlay; R. Hafalia; R. Hannaford; H. Higley; A. Jackson; A. Lietzke; N. Liggins; A. D. McInturff; J. O'Neill; E. Palmerston; G. Sabbi; R. M. Scanlan; J. Swanson

2001-01-01

263

Fabrication and test results of a high field, Nb3Sn superconducting racetrack dipole magnet

The LBNL Superconducting Magnet Program is extending accelerator magnet technology to the highest possible fields. A 1 meter long, racetrack dipole magnet, utilizing state-of-the-art Nb{sub 3}Sn superconductor, has been built and tested. A record dipole filed of 14.7 Tesla has been achieved. Relevant features of the final assembly and tested results are discussed.

Benjegerdes, R.; Bish, P.; Byford, D.; Caspi, S.; Dietderich, D.R.; Gourlay, S.A.; Hafalia, R.; Hannaford, R.; Higley, H.; Jackson, A.; Lietzke, A.; Liggins, N.; McInturff, A.D.; O'Neill, J.; Palmerston, E.; Sabbi, G.; Scanlan, R.M.; Swanson, J.

2001-06-15

264

Communication: Theoretical study of ThO for the electron electric dipole moment search

An experiment to search for the electron electric dipole moment (eEDM) on the metastable H{sup 3}?{sub 1} state of ThO molecule was proposed and now prepared by the ACME Collaboration [ http://www.electronedm.org ]. To interpret the experiment in terms of eEDM and dimensionless constant k{sub T,} {sub P} characterizing the strength of the T,P-odd pseudoscalarscalar electronnucleus neutral current interaction, an accurate theoretical study of an effective electric field on electron, E{sub eff}, and a parameter of the T,P-odd pseudoscalarscalar interaction, W{sub T,} {sub P}, in ThO is required. We report our results for E{sub eff} (84 GV/cm) and W{sub T,} {sub P} (116 kHz) together with the hyperfine structure constant, molecule frame dipole moment, and H{sup 3}?{sub 1} ? X{sup 1}?{sup +} transition energy, which can serve as a measure of reliability of the obtained E{sub eff} and W{sub T,} {sub P} values. Besides, our results include a parity assignment and evaluation of the electric-field dependence for the magnetic g factors in the ?-doublets of H{sup 3}?{sub 1}.

Skripnikov, L. V., E-mail: leonidos239@gmail.com; Petrov, A. N.; Titov, A. V. [Federal State Budgetary Institute Petersburg Nuclear Physics Institute, Gatchina, Leningrad district 188300 (Russian Federation) [Federal State Budgetary Institute Petersburg Nuclear Physics Institute, Gatchina, Leningrad district 188300 (Russian Federation); Department of Physics, Saint Petersburg State University, Saint Petersburg, Petrodvoretz 198904 (Russian Federation)

2013-12-14

265

Magnetic dipole transitions in 4d{sup N} configurations of tungsten ions

Magnetic dipole transitions between the levels of ground 4d{sup N} configurations of tungsten ions were analyzed by employing a large basis of interacting configurations. Previously introduced configuration interaction strength between two configurations was used to determine the configurations with the largest contribution to wave functions of atomic states for the considered configurations. Collisional-radiative modeling was performed for the levels of the ground configuration coupled through electric dipole transitions with 4p{sup 5}4d{sup N+1} and 4d{sup N-1}4f configurations. New identification of some lines observed in the electron-beam ion trap plasma was proposed based on calculations in which wavelength convergence was reached.

Jonauskas, V.; Kisielius, R.; Kyniene, A.; Kucas, S.; Norrington, P. H. [Institute of Theoretical Physics and Astronomy, Vilnius University, A. Gostauto 12, LT-01108 Vilnius (Lithuania); Department of Applied Mathematics and Theoretical Physics, Queen's University of Belfast, Belfast BT7 1NN, Northern Ireland, United Kingdon (United Kingdom)

2010-01-15

266

LABORATORY VI ELECTRICITY FROM MAGNETISM

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

Minnesota, University of

267

First experimental evidence of a giant permanent electric-dipole moment in cellulose nanocrystals

NASA Astrophysics Data System (ADS)

The existence of a permanent electric dipole in cellulose nanocrystals (CNCs) has been evidenced by designed rectangular reversing pulse experiments. Transient electric birefringence (TEB) was used to measure the orientation under electric fields of CNCs dispersed in an apolar solvent (toluene) at low volume fraction. We probed the static and the dynamic orientational behaviour of CNCs in order to evaluate both the permanent and induced electric-dipole contributions to the orientational order parameter S2. We demonstrated the presence of a permanent dipole \\mu_p of about 4400+/-400 Debye along the CNCs long axis. The existence of this permanent dipole can stem from the parallel arrangement of cellulose chains in a non-centrosymmetric crystallographic lattice within each CNC together with the dipole moment borne by each glucosyl monomer.

Frka-Petesic, Bruno; Jean, Bruno; Heux, Laurent

2014-07-01

268

NASA Technical Reports Server (NTRS)

A number of energy momentum anomalies are described that result from the use of Abraham-Lorentz electromagnetic theory. These anomalies have in common the motion of charged bodies or current carrying conductors relative to the observer. The anomalies can be avoided by using the nonflow approach, based on internal energy of the electromagnetic field. The anomalies can also be avoided by using the flow approach, if all contributions to flow work are included. The general objective of this research is a fundamental physical understanding of electric and magnetic fields which, in turn, might promote the development of new concepts in electric space propulsion. The approach taken is to investigate quantum representations of these fields.

Kaufman, H. R.; Robinson, R. S.; Etters, R. D.

1982-01-01

269

NASA Astrophysics Data System (ADS)

When calculating the interaction between electric field-induced dipoles, the dipole moments are often taken to be equal to their polarizability multiplied by the external electric field. However, this approach is not exact, since it does not take into account the fact that particles with a dipole moment affect the local electric field experienced by other particles. In this work, we employ the Coupled Dipole Method to calculate the electric-field-induced dipole pair interaction self-consistently: that is, we take into account many-body effects on the individual induced dipole moments. We calculate interactions of particles with nonvanishing dimensions by splitting them up into self-consistently inducible "chunks" of polarizable matter. For point dipoles, spheres, cubes, rods, and dumbbells, we discuss the differences and commonalities between our self-consistent approach and the aforementioned approach of pre-assigning dipole moments to either the point dipoles or, in the case of spatially extended particles, to the chunks making up the particle.

Kwaadgras, Bas W.; van Roij, René; Dijkstra, Marjolein

2014-04-01

270

We propose to use ferroelectric (Eu,Ba)TiO{sub 3} ceramics just above their magnetic ordering temperature for a sensitive electron electric-dipole-moment search. We have synthesized a number of such ceramics with various europium concentrations and measured their properties relevant for such a search: permeability, magnetization noise, and ferroelectric hysteresis loops. We also identify and estimate the likely systematics: the magnetoelectric effect, hysteresis-loop heating, and ferroelectric relaxation currents. Our measurements and estimates indicate that a search for the electron electric dipole moment with Eu{sub 0.5}Ba{sub 0.5}TiO{sub 3} could lead to an order of magnitude improvement on the current best limit, if the systematic effects can be controlled.

Sushkov, A. O.; Eckel, S.; Lamoreaux, S. K. [Yale University, Department of Physics, P. O. Box 208120, New Haven, Connecticut 06520-8120 (United States)

2010-02-15

271

EPICS Slow Controls System in the Search for a Neutron Electric Dipole Moment

NASA Astrophysics Data System (ADS)

The measurement of a nonzero electric dipole moment (EDM) of the neutron would significantly impact our understanding of the nature of the electro-weak and strong interactions. The goal of the current experiment is to improve the measurement sensitivity of the EDM by two orders of magnitude. The experiment is based on the magnetic-resonance technique of rotating a magnetic dipole moment in a magnetic field. The measurement of the neutron EDM comes from a measurement of the difference in the precession frequencies of neutrons when a strong electric field parallel to the magnetic field is reversed. This construction project is divided into a number of subsystems, five of which require automated control. The Experimental Physics and Industrial Control System (EPICS) is a slow-controls data acquisition (DAQ) system and is the system of choice for this experiment. It was selected for both its ease of use and ability to act as a total control system for large systems. As part of the initial research and development for the EDM project, we are setting up a prototype system that will eventually be copied and sent to the subsystem managers. This prototype consists of a VME crate housing a single board computer and DAQ modules. EPICS, running on a PC with CentOS Linux-x86, interfaces with the VME single board computer and provides a graphical user interface for the control system. The details on building this prototype DAQ system will be presented. Supported in part by the U.S. DoE.

Taylor, Courtney

2006-10-01

272

Nonadiabatic behavior of the magnetic moment of a charged particle in a dipole magnetic field

NASA Technical Reports Server (NTRS)

This paper investigates the dynamic behavior of the magnetic moment of a particle confined in a magnetic dipole field in the presence of a low-frequency electrostatic wave. It is shown that there exist two kinds of resonances (the bounce-E x B drift resonance and the wave-drift resonance) by which the adiabaticity of the magnetic moment is broken. The unstable conditions obtained by theoretical considerations showed good agreement with the numerical results.

Murakami, Sadayoshi; Sato, Tetsuya; Hasegawa, Akira

1990-01-01

273

Coil end design for the LHC dipole magnet

This paper describes the design of the coil ends for the Large Hadron Collider dipole magnets of the CERN European Laboratory for Particle Physics in Switzerland. This alternative to existing European designs was provided by Fermi National Accelerator Laboratory by agreement between CERN and the United States. The superconducting cable paths are determined from both magnetic and mechanical considerations. The coil end parts used to shape and constrain the conductors in the coil ends are designed using the developable surface, grouped end approach. This method allows the analysis of strain energy within the conductor groups, and the optimization of mechanical factors during the design. Design intent and implementation are discussed. Inner and outer coil design challenges and end analysis are detailed.

Brandt, J.S.

1996-05-21

274

NASA Astrophysics Data System (ADS)

To study the influence of coated-conductor magnetization on the field quality of accelerator magnets, we made a small dipole magnet consisting of four racetrack coils wound with GdBCO coated conductors and measured its magnetic field in liquid nitrogen by using rotating pick-up coils. We focused on the dipole and sextupole components (coefficients) of the magnetic field, which vary with time owing to the decay of the magnetization of the coated conductors. About 50 min (3055 s) after the current was ramped up to 50 A, the dipole coefficient normalized by the design value of the dipole component, i.e., the value calculated with the designed coil shape and the uniform current distribution in the coated conductors, increased by 7.4 × 10?4, and the sextupole coefficient normalized by the design value of the dipole component increased by 1.8 × 10?4. The magnitudes of the dipole and sextupole components depended on the excitation history of the magnet. Electromagnetic field analyses were carried out to calculate the current distributions in coated conductors, considering their superconducting properties; the dipole and sextupole coefficients were then determined from the calculated current distributions. Although the analyses were based on the two-dimensional approximation of the cross-section of the magnet, the temporal behaviours as well as the hysteretic characteristics of the calculated dipole and sextupole coefficients agree qualitatively with those of the dipole and sextupole coefficients measured in the magnet.

Amemiya, Naoyuki; Otake, Hiroaki; Sano, Takuya; Nakamura, Taketsune; Ogitsu, Toru; Koyanagi, Kei; Kurusu, Tsutomu

2015-03-01

275

The electric and weak electric dipole form factors for heavy fermions are calculated in the context of the most general two-Higgs-doublet model (2HDM). We find that the large top mass can produce a significant enhancement of the electric dipole form factor in the case of the b and c quarks. This effect can be used to distinguish between different 2HDM scenarios.

Daniel Gomez-Dumm; G. A. Gonzalez-Sprinberg

1999-05-03

276

An experimental search for the electron Electric Dipole Moment in Gadolinium Gallium Garnet

NASA Astrophysics Data System (ADS)

A discovery of a permanent electric dipole moment of the electron (eEDM) would provide crucial information about the nature of T-violation and imply new sources of CP-violation beyond the Standard Model. While the leading experimental technique used to measure EDM is based on the nuclear magnetic resonance, we are pursuing research that would improve the present experimental limit of the eEDM using a new technique in solid-state systems at low temperatures. The experiment uses a paramagnetic insulator Gadolinium Gallium Garnet with a large magnetic response. The presence of the eEDM leads to a finite magnetization when the garnet sample is subjected to a strong electric field. The resulting magnetization can be measured using the Superconducting Quantum Interference Device (SQUID) as a sensitive magnetometer. In this talk, we will discuss the progress to control the systematic effects and improve the sensitivity. The major efforts include the design and implementation of a 24-bit data acquisition system with ultra-low level of channel crosstalk, and the control of the high voltage drift from the supply. With these considerable progresses, we report our first background-free experimental limit of the eEDM on the order of 10-24 e.cm .

Kim, Young Jin; Liu, Chen-Yu

2011-04-01

277

Stable orbital motion of magnetic dipole in the field of permanent magnets

NASA Astrophysics Data System (ADS)

In this paper we aim to give a constructive proof of the existence of stable orbital motions of the bodies in the systems which interact only via magnetic forces. To demonstrate this, we give an example of a magnetic system for which we analytically prove G?-stability. We study the dynamics of a small magnetic body, a magnetic dipole, that performs the quasi-orbital motion in the field of two fixed magnetic poles of opposite signs placed at the systems axis. We use the generalized energy-momentum method to find the conditions of stability of relative equilibria. We also give the realizable physical parameters of the system.

Zub, Stanislav S.

2014-05-01

278

Model Dependence of the 2H Electric Dipole Moment

Background: Direct measurement of the electric dipole moment (EDM) of the neutron lies in the future; measurement of a nuclear EDM may well come first. The deuteron is one nucleus for which exact model calculations are feasible. Purpose: We explore the model dependence of deuteron EDM calculations. Methods: Using a separable potential formulation of the Hamiltonian, we examine the sensitivity of the deuteron EDM to variation in the nucleon-nucleon interaction. We write the EDM as the sum of two terms, the first depending on the target wave function with plane-wave intermediate states, and the second depending on intermediate multiple scattering in the 3P1 channel, the latter being sensitive to the off-shell behavior of the 3P1 amplitude. Results: We compare the full calculation with the plane-wave approximation result, examine the tensor force contribution to the model results, and explore the effect of short range repulsion found in realistic, contemporary potential models of the deuteron. Conclusions: Because one-pion exchange dominates the EDM calculation, separable potential model calculations will provide an adequate description of the 2H EDM until such time as a better than 10% measurement is obtained.

Iraj R. Afnan; Benjamin F. Gibson

2010-11-22

279

CP-odd Phase Correlations and Electric Dipole Moments

We revisit the constraints imposed by electric dipole moments (EDMs) of nucleons and heavy atoms on new CP-violating sources within supersymmetric theories. We point out that certain two-loop renormalization group corrections induce significant mixing between the basis-invariant CP-odd phases. In the framework of the constrained minimal supersymmetric standard model (CMSSM), the CP-odd invariant related to the soft trilinear A-phase at the GUT scale, theta_A, induces non-trivial and distinct CP-odd phases for the three gaugino masses at the weak scale. The latter give one-loop contributions to EDMs enhanced by tan beta, and can provide the dominant contribution to the electron EDM induced by theta_A. We perform a detailed analysis of the EDM constraints within the CMSSM, exhibiting the reach, in terms of sparticle spectra, which may be obtained assuming generic phases, as well as the limits on the CP-odd phases for some specific parameter points where detailed phenomenological studies are available. We also illustrate how this reach will expand with results from the next generation of experiments which are currently in development.

Keith A. Olive; Maxim Pospelov; Adam Ritz; Yudi Santoso

2005-09-16

280

Generalized Wannier functions: A comparison of molecular electric dipole polarizabilities

NASA Astrophysics Data System (ADS)

Localized Wannier functions provide an efficient and intuitive means by which to compute dielectric properties from first principles. They are most commonly constructed in a post-processing step, following total-energy minimization. Nonorthogonal generalized Wannier functions (NGWFs) [Skylaris , Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.66.035119 66, 035119 (2002); Skylaris , J. Chem. Phys.JCPSA60021-960610.1063/1.1839852 122, 084119 (2005)] may also be optimized in situ, in the process of solving for the ground-state density. We explore the relationship between NGWFs and orthonormal, maximally localized Wannier functions (MLWFs) [Marzari and Vanderbilt, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.56.12847 56, 12847 (1997); Souza, Marzari, and Vanderbilt, Phys. Rev. BPRBMDO1098-012110.1103/PhysRevB.65.035109 65, 035109 (2001)], demonstrating that NGWFs may be used to compute electric dipole polarizabilities efficiently, with no necessity for post-processing optimization, and with an accuracy comparable to MLWFs.

O'Regan, David D.; Payne, Mike C.; Mostofi, Arash A.

2012-05-01

281

Search for the Electric Dipole Moment of RADIUM-225

NASA Astrophysics Data System (ADS)

The nuclear Schiff moment and its resulting atomic electric dipole moment (EDM) are signatures of time-reversal and parity violation. They represent an important window onto physics beyond the Standard Model. We are developing a next generation experiment to search for the Schiff moment and EDM of 225Ra (t1/2 = 15 d) based on laser-cooled and -trapped radium atoms. Due to octupole deformation of the nucleus, 225Ra is predicted to be 2-3 orders of magnitude more sensitive to T-violating interactions than 199Hg (stable), which currently sets the most stringent limits in the nuclear sector. At present, 225Ra samples at the level of a few mCi (~ 1014 atoms) are available from the decay of the long-lived 229Th in stock. A future ISOL facility driven by a high-intensity accelerator could deliver 4-5 orders of magnitude more 225Ra. It holds the potential to further improve the EDM search sensitivity.

Holt, Roy J.; Lu, Zheng-Tian; Mueller, Peter

2010-06-01

282

CP-odd phase correlations and electric dipole moments

We revisit the constraints imposed by electric dipole moments (EDMs) of nucleons and heavy atoms on new CP-violating sources within supersymmetric theories. We point out that certain two-loop renormalization group corrections induce significant mixing between the basis-invariant CP-odd phases. In the framework of the constrained minimal supersymmetric standard model, the CP-odd invariant related to the soft trilinear A-phase at the grand unified theory (GUT) scale, {theta}{sub A}, induces nontrivial and distinct CP-odd phases for the three gaugino masses at the weak scale. The latter give one-loop contributions to EDMs enhanced by tan{beta}, and can provide the dominant contribution to the electron EDM induced by {theta}{sub A}. We perform a detailed analysis of the EDM constraints within the constrained minimal supersymmetric standard model, exhibiting the reach, in terms of sparticle spectra, which may be obtained assuming generic phases, as well as the limits on the CP-odd phases for some specific parameter points where detailed phenomenological studies are available. We also illustrate how this reach will expand with results from the next generation of experiments which are currently in development.

Olive, Keith A. [W.I. Fine Theoretical Physics Institute, School of Physics and Astronomy, University of Minnesota, Minneapolis, Minnesota 55455 (United States); Pospelov, Maxim [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 (Canada); Department of Physics and Astronomy, University of Victoria, Victoria, BC, V8P 1A1 (Canada); Ritz, Adam [Theoretical Division, Department of Physics, CERN, Geneva 23, CH-1211 (Switzerland); Santoso, Yudi [Department of Physics, University of Guelph, Guelph, Ontario N1G 2W1 (Canada); Perimeter Institute for Theoretical Physics, Waterloo, Ontario N2J 2W9 (Canada)

2005-10-01

283

Limits on CP nonconserving interactions from electric dipole moments

I discuss bounds on CP-nonconserving (CPNC) and parity-nonconserving (PNC) hadronic interactions that result from measurements of atomic electric dipole moments. In most models of hadronic CPNC, the nuclear edm arises primarily from the polarization of the ground state by the CPNC PNC NN interaction, rather than from the edms of valence nucleons. When the atom is placed in an external field, the nucleus is fully shielded apart from nuclear finite size effects and relativistic corrections arising from hyperfine interactions, so that careful atomic calculations must be performed to deduce the residual sensitivity to the nuclear edm. I describe these shielding effects qualitatively, and present results from more detailed calculations. Atomic limits, when translated into effective bounds on the neutron edm, have now reached sensitivities that are comparable to direct neutron edm limits. I also discuss limits that can be extracted on CPNC parity-conserving (PC) hadronic interactions. Such interactions can generate atomic edms when combined with weak radiative corrections.

Haxton, W.C.

1994-09-01

284

Bs Mixing and Electric Dipole Moments in MFV

We analyze the general structure of four-fermion operators capable of introducing CP-violation preferentially in Bs mixing within the framework of Minimal Flavor Violation. The effect requires a minimum of O(Yu^4 Yd^4) Yukawa insertions, and at this order we find a total of six operators with different Lorentz, color, and flavor contractions that lead to enhanced Bs mixing. We then estimate the impact of these operators and of their close relatives on the possible sizes of electric dipole moments (EDMs) of neutrons and heavy atoms. We identify two broad classes of such operators: those that give EDMs in the limit of vanishing CKM angles, and those that require quark mixing for the existence of non-zero EDMs. The natural value for EDMs from the operators in the first category is up to an order of magnitude above the experimental upper bounds, while the second group predicts EDMs well below the current sensitivity level. Finally, we discuss plausible UV-completions for each type of operator.

Brian Batell; Maxim Pospelov

2010-07-23

285

Search For A Permanent Electric Dipole Moment Using Atomic Indium

We propose indium (In) as a possible candidate for observing the permanent electric dipole moment (EDM) arising from the violations of parity (P) and time-reversal (T) symmetries. This atom has been laser cooled and therefore the measurement of its EDM has the potential of improving on the current best EDM limit for a paramagnetic atom which comes from thallium. We report the results of our calculations of the EDM enhancement factor due to the electron EDM and the ratio of the atomic EDM to the electron-nucleus scalar-pseudoscalar (S-PS) interaction coupling constant in In in the framework of the relativistic coupled cluster theory. It might be possible to get new limits for the electron EDM and the S-PS CP violating coupling constant by combining the results of our calculations with the measured value of the EDM of In when it is available. These limits could have important implications for the standard model (SM) of particle physics.

Sahoo, B K; Das, B P; 10.1103/PhysRevA.84.030502

2011-01-01

286

Model dependence of the H2 electric dipole moment

NASA Astrophysics Data System (ADS)

Background: Direct measurement of the electric dipole moment (EDM) of the neutron is in the future; measurement of a nuclear EDM may well come first. The deuteron is one nucleus for which exact model calculations are feasible. Purpose: We explore the model dependence of deuteron EDM calculations. Methods: Using a separable potential formulation of the Hamiltonian, we examine the sensitivity of the deuteron EDM to variation in the nucleon-nucleon interaction. We write the EDM as the sum of two terms, the first depending on the target wave function with plane-wave intermediate states, and the second depending on intermediate multiple scattering in the 3P1 channel, the latter being sensitive to the off-shell behavior of the 3P1 amplitude. Results: We compare the full calculation with the plane-wave approximation result, examine the tensor force contribution to the model results, and explore the effect of short-range repulsion found in realistic, contemporary potential models of the deuteron. Conclusions: Because one-pion exchange dominates the EDM calculation, separable potential model calculations will provide an adequate description of the H2 EDM until such time as a measurement better than 10% is obtained.

Afnan, I. R.; Gibson, B. F.

2010-12-01

287

Magnetic Design and Code Benchmarking of the SMC (Short Model Coil) Dipole Magnet

The Short Model Coil (SMC) working group was set in February 2007 to complement the Next European Dipole (NED) program, in order to develop a short-scale model of a Nb3Sn dipole magnet. In 2009, the EuCARD/HFM (High Field Magnets) program took over these programs. The SMC group comprises four laboratories: CERN/TE-MSC group (CH), CEA/IRFU (FR), RAL (UK) and LBNL (US). The SMC magnet is designed to reach a peak field of about 13 Tesla (T) on conductor, using a 2500 A/mm2 Powder-In-Tube (PIT) strand. The aim of this magnet device is to study the degradation of the magnetic properties of the Nb3Sn cable, by applying different levels of pre-stress. To fully satisfy this purpose, a versatile and easy-to-assemble structure has been realized. The design of the SMC magnet has been developed from an existing dipole magnet, the SD01, designed, built and tested at LBNL with support from CEA. The goal of the magnetic design presented in this paper is to match the high field region with the high stress region, located alo...

Manil, P; Rochford, J; Fessia, P; Canfer, S; Baynham, E; Nunio, F; de Rijk, G; Védrine, P

2010-01-01

288

Muon anomalous magnetic dipole moment in supersymmetric theories

We study the muon anomalous magnetic dipole moment in supersymmetric theories. The impact of the recent Brookhaven E821 experimental measurement on both model-independent and model-dependent supersymmetric parameter spaces is discussed in detail. We find that values of tan\\beta as low as 3 can be obtained while remaining within the E821 one-sigma bound. This requires a light smuon; however, we show that, somewhat surprisingly, no model-independent bound can be placed on the mass of the lightest chargino for any tan\\beta greater than or equal to 3. We also show that the maximum contributions to the anomalous magnetic moment are insensitive to CP-violating phases. We provide analyses of the supersymmetric contribution to the muon anomalous magnetic moment in dilaton-dominated supergravity models and gauge-mediated supersymmetry-breaking models. Finally, we discuss how other phenomena, such as $B(b\\to s\\gamma)$, relic abundance of the lightest superpartner, and the Higgs mass may be correlated with the anomalous magnetic moment, but do not significantly impact the viability of a supersymmetric explanation, or the mass limits obtainable on smuons and charginos.

Stephen P. Martin; James D. Wells

2001-03-06

289

Observation of Centrifugally Driven Interchange Instabilities in a Plasma Confined by a Magnetic) Centrifugally driven interchange instabilities are observed in a laboratory plasma confined by a dipole magnetic electrostatic dipole vortex [3] that transports mass, energy, and charge [4]. The centrifugally driven

Mauel, Michael E.

290

Center for Gravity, Electrical & Magnetic Studies

Center for Gravity, Electrical & Magnetic Studies Colorado School of Mines CGEMGravity&Magnetics for the sponsors of the Gravity & Magnetics Research Consortium İ Gravity and Magnetics Research Consortium, 2009

291

After the review board for LHC series magnet measurements, the reviewers strongly recommended the installation of two current taps in the pre-series and series dipole magnets. The function of the two additional current taps will be to allow the measurement of the magnetic alignment of the dipole magnets. This note contains the laboratory tests results and a recommendation for the type of wire that shall be used.

Bozzini, D

2000-01-01

292

Micromagnetic Analysis of Effective Magnetic Dipole Position in Magnetic Force Microscope Tip

An accurate micromagnetic model of the magnetic force microscope (MFM) tip has been developed to calculate the effective dipole and its position in a simple point probe model, which are important in the quantitative explanation of MFM images. The pyramid-shaped MFM tips are considered in this paper; so cuboid cells in the body, as well as triangular prism and quadrangle

Hongjia Li; Yi Wang; Sumei Wang; Hai Zhong; Dan Wei

2010-01-01

293

Frequency generation by a magnetic vortex-antivortex dipole in spin-polarized current

A vortex-antivortex (VA) dipole may be generated due to a spin-polarized current flowing through a nano-aperture in a magnetic element. We study the vortex dipole dynamics using the Landau-Lifshitz equation in the presence of an in-plane applied magnetic field and a Slonczewski spin-torque term with in-plane polarization. We establish that the vortex dipole is set in steady state rotational motion. The frequency of rotation is due to two independent forces: the interaction between the two vortices and the external magnetic field. The nonzero skyrmion number of the dipole is responsible for both forces giving rise to rotational dynamics. The spin-torque acts to stabilize the vortex dipole motion at a definite vortex-antivortex separation distance. We give analytical and numerical results for the angular frequency of rotation and VA dipole features as functions of the parameters.

Komineas, Stavros

2012-01-01

294

Frequency generation by a magnetic vortex-antivortex dipole in spin-polarized current

A vortex-antivortex (VA) dipole may be generated due to a spin-polarized current flowing through a nano-aperture in a magnetic element. We study the vortex dipole dynamics using the Landau-Lifshitz equation in the presence of an in-plane applied magnetic field and a Slonczewski spin-torque term with in-plane polarization. We establish that the vortex dipole is set in steady state rotational motion. The frequency of rotation is due to two independent forces: the interaction between the two vortices and the external magnetic field. The nonzero skyrmion number of the dipole is responsible for both forces giving rise to rotational dynamics. The spin-torque acts to stabilize the vortex dipole motion at a definite vortex-antivortex separation distance. We give analytical and numerical results for the angular frequency of rotation and VA dipole features as functions of the parameters.

Stavros Komineas

2012-03-05

295

NASA Astrophysics Data System (ADS)

Magnetic susceptibility measurements were carried out for magnetite-based fluids over a wide temperature range. The fluids were stabilized with commonly used surfactants (fatty acids) and new surfactants (polypropylene glycol and tallow acids). The coefficients of temperature dependence of the particle magnetic moments were determined by fitting of the measured and calculated values of magnetic susceptibility. The influence of the inter-particle dipole-dipole interaction on the susceptibility was taken into account in the framework of A.O. Ivanov's model. The corrections for thermal expansion were determined by density measurements of the carrier fluid. The obtained values of temperature coefficients correlate to the solidification temperature of the fluid samples. For fluids with a low solidification temperature the value of the temperature coefficient of particle magnetization coincides with its value for bulk magnetite.

Lebedev, A. V.

2015-01-01

296

Confinement of electron plasma by levitating dipole magnet

A recent experiment on the Ring Trap 1 device has demonstrated long-term (exceeding 300 s) confinement of non-neutral (pure electron) plasma in a dipole magnetic field; particles diffuse inward, steepening the density gradient and self-organizing into a stable vortex structure [Z. Yoshida et al., Phys. Rev. Lett. 104, 235004 (2010)]. In this study, the internal structures of the plasma are experimentally investigated, and it is shown that the observations are consistent with rigidly rotating charged particle clump. The radial profiles of electrostatic potential and electron density consistently show that the drift velocity has homogeneous angular frequency in the confinement region. The electrostatic fluctuations also rotate rigidly with a phase velocity that agrees with the drift velocity. The magnetospheric system should have a wide application in confining single-species and even multiple-species charged particles.

Saitoh, H.; Yoshida, Z.; Morikawa, J.; Yano, Y.; Hayashi, H.; Mizushima, T.; Kawai, Y.; Kobayashi, M.; Mikami, H. [Department of Advanced Energy, Graduate School of Frontier Sciences, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)

2010-11-15

297

CryoEDM: A cryogenic experiment to measure the neutron electric dipole moment

NASA Astrophysics Data System (ADS)

CryoEDM is an experiment that aims to measure the electric dipole moment (EDM) of the neutron to a precision of 10 -28 e cm. A description of CryoEDM, the apparatus, technologies and commissioning is presented.

van der Grinten, M. G. D.; CryoEDM Collaboration; Balashov, S. N.; Francis, V.; Green, K.; Iaydjiev, P. S.; Ivanov, S. N.; Khazov, A.; Tucker, M. A. H.; Wark, D. L.; Davidson, A.; Hardiman, M.; Harris, P. G.; Katsika, K.; Pendlebury, J. M.; Peeters, S. J. M.; Shiers, D. B.; Smith, P.; Townsley, C.; Wardell, I.; Clarke, C.; Henry, S.; Kraus, H.; McCann, M.; Geltenbort, P.; Yoshiki, Y.

2009-12-01

298

ANALYTICAL CALCULATION OF STOKES PROFILES OF ROTATING STELLAR MAGNETIC DIPOLE

The observation of the polarization emerging from a rotating star at different phases opens up the possibility to map the magnetic field in the stellar surface thanks to the well-known Zeeman-Doppler imaging. When the magnetic field is sufficiently weak, the circular and linear polarization profiles locally in each point of the star are proportional to the first and second derivatives of the unperturbed intensity profile, respectively. We show that the weak-field approximation (for weak lines in the case of linear polarization) can be generalized to the case of a rotating star including the Doppler effect and taking into account the integration on the stellar surface. The Stokes profiles are written as a linear combination of wavelength-dependent terms expressed as series expansions in terms of Hermite polynomials. These terms contain the surface-integrated magnetic field and velocity components. The direct numerical evaluation of these quantities is limited to rotation velocities not larger than eight times the Doppler width of the local absorption profiles. Additionally, we demonstrate that in a rotating star, the circular polarization flux depends on the derivative of the intensity flux with respect to the wavelength and also on the profile itself. Likewise, the linear polarization depends on the profile and on its first and second derivatives with respect to the wavelength. We particularize the general expressions to a rotating dipole.

Martinez Gonzalez, M. J. [Instituto de Astrofisica de Canarias, Via Lactea s/n, 38200 La Laguna, Tenerife (Spain); Asensio Ramos, A. [Departamento de Astrofisica, Universidad de La Laguna, E-38205 La Laguna, Tenerife (Spain)

2012-08-20

299

Trapped ion emulation of electric dipole moment of neutral relativistic particles

The electric dipole moments of various neutral elementary particles, such as neutron, neutrinos, certain hypothetical dark matter particles and others, are predicted to exist by the standard model of high energy physics and various extensions of it. However, the predicted values are beyond the present experimental capabilities. We propose to simulate and emulate the electric dipole moment of neutral relativistic particles and the ensuing effects in the presence of electrostatic field by emulation of an extended Dirac equation in ion traps.

Tihomir G. Tenev; Peter A. Ivanov; Nikolay V. Vitanov

2012-09-06

300

Purcell factor of Mie resonators featuring electric and magnetic modes

We present a modal approach to compute the Purcell factor in Mie resonators exhibiting both electric and magnetic resonances. The analytic expressions of the normal modes are used to calculate the effective volumes. We show that important features of the effective volume can be predicted thanks to the translation-addition coefficients of a displaced dipole. Using our formalism, it is easy to see that, in general, the Purcell factor of Mie resonators is not dominated by a single mode, but rather by a large superposition. Finally we consider a silicon resonator homogeneously doped with electric dipolar emitters, and we show that the average electric Purcell factor dominates over the magnetic one.

Zambrana-Puyalto, Xavier

2015-01-01

301

Theoretical Prediction and Impact of Fundamental Electric Dipole Moments

The predicted Standard Model (SM) electric dipole moments (EDMs) of electrons and quarks are tiny, providing an important window to observe new physics. Theories beyond the SM typically allow relatively large EDMs. The EDMs depend on the relative phases of terms in the effective Lagrangian of the extended theory, which are generally unknown. Underlying theories, such as string/M-theories compactified to four dimensions, could predict the phases and thus EDMs in the resulting supersymmetric (SUSY) theory. Earlier one of us, with collaborators, made such a prediction and found, unexpectedly, that the phases were predicted to be zero at tree level in the theory at the unification or string scale $\\sim\\mathcal{O}(10^{16}$ GeV). Electroweak (EW) scale EDMs still arise via running from the high scale, and depend only on the SM Yukawa couplings that also give the CKM phase. Here we extend the earlier work by studying the dependence of the low scale EDMs on the constrained but not fully known fundamental Yukawa couplings. The dominant contribution is from two loop diagrams and is not sensitive to the choice of Yukawa texture. The electron EDM should not be found to be larger than about $ 5\\times 10^{-30} e$ cm, and the neutron EDM should not be larger than about $5\\times 10^{-29}e$ cm. These values are quite a bit smaller than the reported predictions from Split SUSY and typical effective theories, but much larger than the Standard Model prediction. Also, since models with random phases typically give much larger EDMs, it is a significant testable prediction of compactified M-theory that the EDMs should not be above these upper limits. The actual EDMs can be below the limits, so once they are measured they could provide new insight into the fundamental Yukawa couplings of leptons and quarks. We comment also on the role of strong CP violation. EDMs probe fundamental physics near the Planck scale.

Sebastian A. R. Ellis; Gordon L. Kane

2014-05-29

302

Dynamical interaction effects on an electric dipole moving parallel to a flat solid surface

NASA Astrophysics Data System (ADS)

The interaction experienced by a fast electric dipole moving parallel and close to a flat solid surface is studied using the dielectric formalism. Analytical expressions for the force acting on the dipole, for random and for particular orientations, are obtained. Several features related to the dynamical effects on the induced forces are discussed, and numerical values are obtained for the different cases. The calculated energy loss of the electric dipole provides useful estimations which could be of interest for small-angle scattering experiments using polar molecules.

Villó-Pérez, Isidro; Abril, Isabel; Garcia-Molina, Rafael; Arista, Néstor R.

2005-05-01

303

NASA Astrophysics Data System (ADS)

Resonant energy transfers, the non-radiative redistribution of an electronic excitation between two particles coupled by the dipole-dipole interaction, lie at the heart of a variety of phenomena, notably photosynthesis. In 1948, Förster established the theory of fluorescence resonant energy transfer (FRET) between broadband, nearly-resonant donors and acceptors. The 1/R6 scaling of the energy transfer rate, where R is the distance between particles, enabled widespread use of FRET as a `spectroscopic ruler for determining nanometric distances in biomolecules. The underlying mechanism is a coherent dipolar coupling between particles, as recognized in the early days of quantum mechanics, but this coherence has not been directly observed so far. Here we study, spectroscopically and in the time domain, the coherent, dipolar-induced exchange of excitations between two Rydberg atoms separated by up to 15 ?m, and brought into resonance by applying an electric field. Coherent oscillation of the system between two degenerate pair states then occurs at a frequency scaling as 1/R3, the hallmark of resonant dipole-dipole interactions. Our results not only demonstrate, at the fundamental level of two atoms, the basic mechanism underlying FRET, but also open exciting prospects for active tuning of strong, coherent interactions in quantum many-body systems.

Ravets, Sylvain; Labuhn, Henning; Barredo, Daniel; Béguin, Lucas; Lahaye, Thierry; Browaeys, Antoine

2014-12-01

304

Permanent dipole magnets for the 8 GeV transfer line at FNAL

The transfer line that will serve to transport 8 GeV protons from the Booster to the new Fermilab Main Injector has been built using permanent magnets. A total of 46 horizontal bend dipoles and 5 vertical bend dipoles were built for this beamline; 67 gradient magnets were also built. The magnets were built using magnetized strontium ferrite bricks. Thermal compensation of these bricks was effected by use of a nickel-iron alloy. The dipole magnets were built with a mean integrated strength of 0.56954 T-m, and an rms spread of 0.06%. The magnets were thermally cycled from 20{degrees}C to 0{degrees}C to condition the ferrite against irreversible thermal losses, and the compensation was measured with a flipcoil. The magnet strength was adjusted by varying the number of bricks installed at the magnet ends. Details of the assembly process and a summary of magnetic measurements are presented here.

Glass, H.D.; Brown, B.C.; Foster, G.W.; Fowler, W.B.; Haggard, J.E. [and others

1997-06-01

305

AC magnetic measurements of the ALS Booster Dipole Engineering Model Magnet

10 Hz sine wave and 2 Hz sawtooth AC magnetic measurements of he curved ALS Booster Dipole Engineering Model Magnet have been accomplished. Long curved coils were utilized to measure the integral transfer function and uniformity. Point coils and a Hall Probe were used to measure magnetic induction and its uniformity. The data were logged and processed by a Tektronix 11401 digital oscilloscope. The dependence of the effective length on the field was determined from the ratio of the integral coil signals to the point coil signals. Quadrupole and sextupole harmonics were derived from the point and integral uniformity measurements. 5 refs., 4 figs., 2 tabs.

Green, M.I.; Keller, R.; Nelson, D.H.; Hoyer, E.

1989-03-01

306

Solar rotating magnetic dipole?. [around axis perpendicular to rotation axis of the sun

NASA Technical Reports Server (NTRS)

A magnetic dipole rotating around an axis perpendicular to the rotation axis of the sun can account for the characteristics of the surface large-scale solar magnetic fields through the solar cycle. The polarity patterns of the interplanetary magnetic field, predictable from this model, agree with the observed interplanetary magnetic sector structure.

Antonucci, E.

1974-01-01

307

Gravity-induced electric polarization of matter and planetary magnetic fields

We propose a new mechanism of planetary magnetic field generation based on gravity influence on atomic nuclei of matter inside a planet. This results in displacement of nuclei depthward the centre of a planet, i.e. in polarization of electrically neutral matter and induction of radially directed electric dipoles. Diurnal axial rotation of a planet causes the dipoles to originate circular electric currents producing magnetic field. Calculated magnetic moments of terrestrial and outer planets and some of satellites are compared with their observed values.

Zon, Boris A

2007-01-01

308

Electric and Magnetic Forces: Electric Charges

NSDL National Science Digital Library

Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach.This Science Object is the first of three Science Objects in the Electric and Magnetic Forces SciPack.

National Science Teachers Association (NSTA)

2008-10-30

309

Electric dipole formation at high-k dielectric/SiO2 interface

NASA Astrophysics Data System (ADS)

The formation of an electric dipole at the high-k/SiO2 interface is quantitatively analyzed. The band lineups and physical origin of dipole formation at the high-k/SiO2 interface are explained by the dielectric contact induced gap states (DCIGS). The charge neutrality level (CNL) of the DCIGS, which represents a distribution of high-k and SiO2 contact induced gap states, is utilized to study the dipole moment. The charge transfer due to different CNLs of high-k and SiO2 is considered as the dominant origin of dipole formation. The theoretically calculated dipole strengths of high-k/SiO2 systems based on this model are in good agreement with the experimental data. Project supported by the National Natural Science Foundation of China (No. 61404093), and the Doctoral Scientific Research Foundation of Weifang University (No. 2014BS02).

Kai, Han; Xiaolei, Wang; Hong, Yang; Wenwu, Wang

2015-03-01

310

Search for electric dipole moments of light ions in storage rings

NASA Astrophysics Data System (ADS)

The Standard Model (SM) of Particle Physics is not capable to account for the apparent matterantimatter asymmetry of our Universe. Physics beyond the SM is required and is searched for by (i) employing highest energies (e.g., at LHC), and (ii) striving for ultimate precision and sensitivity (e.g., in the search for electric dipole moments (EDMs)). Permanent EDMs of particles violate both time reversal ( T) and parity ( P) invariance, and are via the CPT-theorem also CP-violating. Finding an EDM would be a strong indication for physics beyond the SM, and pushing upper limits further provides crucial tests for any corresponding theoretical model, e.g., SUSY. Direct searches of proton and deuteron EDMs bear the potential to reach sensitivities beyond 10-29 e cm. For an all-electric proton storage ring, this goal is pursued by the US-based srEDM collaboration [2], while the newly found Julich-based JEDI collaboration [1] is pursuing an approach using a combined electric-magnetic lattice which shall provide access to the EDMs of protons, deuterons, and 3He ions in the same machine. In addition, JEDI has recently proposed to perform a direct measurement of the proton and/or deuteron EDM at COSY using resonant techniques involving Wien filters.

Rathmann, F.; Saleev, A.; Nikolaev, N. N.

2014-01-01

311

Self-force on an electric dipole in the spacetime of a cosmic string

We calculate the electrostatic self-force on an electric dipole in the spacetime generated by a static, thin, infinite and straight cosmic string. The electric dipole is held fixed in different configurations, namely, parallel, perpendicular to the cosmic string and oriented along the azimuthal direction around this topological defect, which is stretched along the z axis. We show that the self-force is equivalent to an interaction of the electric dipole with an effective dipole moment which depends on the linear mass density of the cosmic string and on the configuration. The plots of the self-forces as functions of the parameter which determines the angular deficit of the cosmic string are shown for those different configurations. -- Highlights: Review of regularized Greens function applied to the problem. Self-force on an electric dipole in the string spacetime for some orientations. Representation via graphs of the self-forces versus angular parameter of the cosmic string. Self-force induced by the string seen as an interaction between two dipoles. Discussion about the superposition principle in this non-trivial background.

Muniz, C.R., E-mail: celiomuniz@yahoo.com [Grupo de Física Teórica (GFT), Universidade Estadual do Ceará, UECE-FECLI, Iguatu, Ceará (Brazil); Bezerra, V.B., E-mail: valdir@ufpb.br [Departamento de Física, Universidade Federal da Paraíba, Caixa Postal 5008, CEP 58051-970, Joo Pessoa, PB (Brazil)

2014-01-15

312

Magnetic Fields Analogous to electric field, a magnet

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

Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

313

AC magnetic measurements of the ALS Booster Synchrotron Dipole Magnet engineering model

We made a minimal set of AC magnetic measurements of the engineering model of the ALS Booster Dipole Magnet as part of the process of qualifying its design for production. Magnetic induction integrals over paths approximating electron-beam trajectories were measured with long curved coils connected to an electronic integrator. Magnetic induction was measured with point coils and an integrator and independently with a Hall-effect Gaussmeter. These quantities, and magnet current, were displayed on a commercial digital storage oscilloscope as parametric functions of time. The displayed waveforms were stored, processed and redisplayed as representations of selected magnet parameters. A waveform representing the magnet's effective-length was created by dividing the integral waveform by the magnetic induction waveform. Waveforms of the transfer functions were produced by dividing both the integral waveform and the magnetic induction waveform by the current waveform. Pairs of matched coils, connected in series opposition, provided differential measurements of field uniformity. Quadrupole and sextupole coefficients were derived from the uniformity data. These magnet parameters were measured at 2 and 10 Hz frequencies. Together with measurements of the magnetic field at selected dc levels, the ac measurements demonstrated that the magnet design met specifications and qualified it for production. 7 refs., 7 figs., 3 tabs.

Green, M.I.; Hoyer, E.; Keller, R.; Nelson, D.H.

1988-09-01

314

Energy loss of an electric dipole in a free-electron gas

NASA Astrophysics Data System (ADS)

The energy loss and self-energy of electric dipoles in a free-electron gas are studied using the dielectric function formalism. Analytical expressions for low and high velocities and for different orientations of the dipole axis are obtained and compared with full numerical integrations using Lindhard's dielectric function. The contributions from plasmon and individual excitations are calculated separately. Similar calculations were performed for diclusters or ``extended dipoles'' and for individual protons, and the results are compared. Several features arising from short-range dipolelike interactions are analyzed. Numerical estimations indicate the possibility of carrying out energy loss measurements on the interaction of polar molecules with solids.

Arista, Néstor R.

2002-02-01

315

Neutron and electron electric dipole moment in N=1 supergravity unification

An analysis of the neutron EDM and of the electron EDM in minimal N=1 supergravity unification with two CP-violating phases is given. For the neutron the analysis includes the complete one loop gluino, chargino, and neutralino exchange diagrams for the electric dipole and the chromoelectric dipole operators, and also the contribution of the purely gluonic dimension-six operator. It is shown

Tarek Ibrahim; Pran Nath

1998-01-01

316

Equilibrium state of planar arrays of magnetic dipoles in the presence of exchange interaction

NASA Astrophysics Data System (ADS)

This article investigates the equilibrium states of square-planar arrays of magnetic dipoles. It has been demonstrated that in the presence of an exchange interaction the main equilibrium states are the configurations of dipoles oriented along the system diagonal, along its side, as well as configurations with vortex structures, which may differ by location of the vortex center and, respectively, by magnitude and direction of the magnetic moment of the system. Also the conditions for transitions in the equilibrium configurations, when influenced by a plane field affecting the whole array, or by a normal local field affecting a part of the system dipoles, were considered. The possibility to control magnetic moment of the dipoles system through transitions between different vortex configurations, including a configuration with zero total magnetic moment, has been shown.

Shutyi, Anatolij M.; Eliseeva, Svetlana V.; Sementsov, Dmitrij I.

2015-01-01

317

Cryogenic Design for the Neutron Electric Dipole Moment Experiment

NASA Astrophysics Data System (ADS)

The search for a non-zero neutron electric dipole moment (nEDM) proposed for the Spallation Neutron Source (SNS) is a precision test of time reversal symmetry. Lowering the upper limit on the nEDM, currently 10-26 e·cm, by a factor of 100 will test the validity of extensions to the Standard Model. Measuring a non-zero nEDM would provide a new source of violation of the combined symmetries of charge conjugation and parity that could help explain the matter-antimatter imbalance in the universe. The experiment utilizes ultracold neutrons and polarized 3He atoms in a bath of super fluid 4He at 0.45 K. Cold neutrons from the SNS are slowed and trapped in two 3.1 liter cells by collisions with the 4He. A large dilution refrigerator (DR) cools the cells and a surrounding 1000 liter volume of liquid helium (LHe). In order to ensure that the DR will have adequate cooling power to maintain the bath at 0.45 K we have examined two of the anticipated heat loads. The first heat load comes from transporting polarized 3He throughout the system. Polarized 3He is added to the measurement cells to act as an analyzer of the neutron precession frequency and as a comagnetometer. In the apparatus, an atomic beam of polarized 3He will be injected into a free surface of LHe and then transported to the target cells via heat flush. The 3He atoms depolarize through interactions with the target cell walls and must be removed and replenished prior to each measurement. Activating heaters to sweep the 3He into and out of the target causes a significant heat load on the DR mixing chamber. We have developed a complete thermal model to estimate this heat load and inform the design of the DR heat exchangers. The second heat load arises from the 0.5 inch and larger diameter tubes that connect volumes of super fluid liquid helium under vapor pressure at T ? 0:5 K to volumes at temperatures above the super fluid transition temperature. There are large heat flows due to the creep of super fluid film up the tube and the reflux of warm gas caused by the evaporation of the film at higher temperatures. This effect has been modeled in the literature and previously measured T ? 0.9 K. We have measured this effect in a closed thermal column, cooled to 0.3 K by a dilution refrigerator. Our results test the reflux model at nEDM operating temperature and will guide the design of heat sinks in the nEDM apparatus.

Kendellen, David Patrick

318

A magnetic-dipole vortex is generated in the behind of an ultraintense and ultrashort laser pulse in a near critical density plasma. The vortex is self-sustained by its magnetic field pressure which expels background electrons, and resulting sheath field accelerates electrons to drive high amplitude electric current inside the vortex. The electron energy spectra shows nonthermal distribution with relatively high energy. The vortex is stable for a long period since it is in the electromagnetic equilibrium, whose structure and characteristics are explained by a simple analytical model. PMID:18518547

Nakamura, Tatsufumi; Mima, Kunioki

2008-05-23

319

Heavy polar molecules can be used to measure the electric dipole moment of the electron, which is a sensitive probe of physics beyond the Standard Model. The value is determined by measuring the precession of the molecule's spin in a plane perpendicular to an applied electric field. The longer this precession evolves coherently, the higher the precision of the measurement. For molecules in a trap, this coherence time could be very long indeed. We evaluate the sensitivity of an experiment where neutral molecules are trapped electrically, and compare this to an equivalent measurement in a molecular beam. We consider the use of a Stark decelerator to load the trap from a supersonic source, and calculate the deceleration efficiency for YbF molecules in both strong-field seeking and weak-field seeking states. With a 1 s holding time in the trap, the statistical sensitivity could be ten times higher than it is in the beam experiment, and this could improve by a further factor of five if the trap can be loaded from a source of larger emittance. We study some effects due to field inhomogeneity in the trap and find that rotation of the electric field direction, leading to an inhomogeneous geometric phase shift, is the primary obstacle to a sensitive trap-based measurement. PMID:20151537

Tarbutt, M R; Hudson, J J; Sauer, B E; Hinds, E A

2009-01-01

320

Dynamics of a vortex dipole across a magnetic phase boundary in a spinor Bose-Einstein condensate

NASA Astrophysics Data System (ADS)

The dynamics of a vortex dipole in a spin-1 Bose-Einstein condensate in which magnetic phases are spatially distributed is investigated. When a vortex dipole travels from the ferromagnetic phase to the polar phase, or vice versa, it penetrates the phase boundary and transforms into one of the various spin vortex dipoles, such as a leapfrogging ferromagnetic-core vortex dipole and a half-quantum vortex dipole. Topological connections of spin wave functions across the phase boundary are discussed.

Kaneda, Tomoya; Saito, Hiroki

2014-11-01

321

Ejection of magnetic-field-sensitive atoms from an optical dipole trap

Rubidium atoms prepared by evaporative cooling in an optical dipole trap are used in Stern-Gerlach type experiments. The analysis of the magnetic state distribution in the trap and during free fall demonstrates the possibility of ejecting all atoms with mF!=0 from the optical dipole trap. This is achieved by applying an appropriately located inhomogeneous magnetic field. We investigate the dynamics

C. Käfer; R. Bourouis; J. Eurisch; A. Tripathi; H. Helm

2009-01-01

322

Polarizable vacuum analysis of electric and magnetic fields

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.

Xing-Hao Ye

2009-08-22

323

Structural performance of the first SSC (Superconducting Super Collider) Design B dipole magnet

The first Design B Superconducting Super Collider (SSC) dipole magnet has been successfully tested. This magnet was heavily instrumented with temperature and strain gage sensors in order to evaluate its adherence to design constraints and design calculations. The instrumentation and associated data acquisition system allowed monitoring of the magnet during cooldown, warmup, and quench testing. This paper will focus on

1989-01-01

324

NASA Astrophysics Data System (ADS)

We describe a method for measuring magnetic dipole-dipole interactions, and hence distances, between pairs of like nuclear spins in a many-spin system under magic-angle spinning (MAS). This method employs a homonuclear dipolar recoupling sequence that creates an average dipole-dipole coupling Hamiltonian under MAS with full zero-quantum symmetry, including both secular and flip-flop terms. Flip-flop terms are then attenuated by inserting rotor-synchronized periods of chemical shift evolution between recoupling blocks, leaving an effective Hamiltonian that contains only secular terms to a good approximation. Couplings between specific pairs of nuclear spins can then be selected with frequency-selective ? pulses. We demonstrate this technique, which we call zero-quantum shift evolution assisted homonuclear recoupling, in a series of one-dimensional and two-dimensional C13 NMR experiments at 17.6 T and 40.00 kHz MAS frequency on uniformly C13-labeled L-threonine powder and on the helix-forming peptide MB(i+4)EK, synthesized with a pair of uniformly C13-labeled L-alanine residues. Experimental demonstrations include measurements of distances between C13 sites that are separated by three bonds, placing quantitative constraints on both sidechain and backbone torsion angles in polypeptides.

Hu, Kan-Nian; Tycko, Robert

2009-07-01

325

The three isostructural magnetic oxides MAs2O6 (M = Mn, Co, Ni) containing high-spin M(2+) ions undergo a long-range antiferromagnetic ordering below 30 K, but their ordered magnetic structures are not identical. While CoAs2O6 and NiAs2O6 adopt the commensurate superstructure of q1 = (0, 0, 1/2), MnAs2O6 has the incommensurate superstructure of q2 = (0.055, 0.389, 0.136). The cause for this difference was examined by calculating their spin exchange and magnetic dipole-dipole interaction energies. In CoAs2O6 and NiAs2O6, the strongest M-O···O-M spin exchange, J1, dominates over other exchanges, hence leading to the q1 superstructure. For MnAs2O6, the spin exchanges are not a deciding factor leading to its magnetic superstructure, being all weak and comparable in strengths, but the magnetic dipole-dipole interactions are. PMID:24601528

Koo, Hyun-Joo; Whangbo, Myung-Hwan

2014-04-01

326

Numerical simulations of magnetohydrodynamic (MHD) hypersonic flow over a cylinder are presented for axial- and transverse-oriented dipoles with different strengths. ANSYS CFX is used to carry out calculations for steady, laminar flows at a Mach number of 6.1, with a model for electrical conductivity as a function of temperature and pressure. The low magnetic Reynolds number (?1) calculated based on the velocity and length scales in this problem justifies the quasistatic approximation, which assumes negligible effect of velocity on magnetic fields. Therefore, the governing equations employed in the simulations are the compressible Navier-Stokes and the energy equations with MHD-related source terms such as Lorentz force and Joule dissipation. The results demonstrate the ability of the magnetic field to affect the flowfield around the cylinder, which results in an increase in shock stand-off distance and reduction in overall temperature. Also, it is observed that there is a noticeable decrease in drag with the addition of the magnetic field. PMID:24307870

Guarendi, Andrew N.; Chandy, Abhilash J.

2013-01-01

327

Permanent electric dipole moments are important for understanding symmetry breaking in molecular physics, control of chemical reactions, and realization of strongly correlated many-body quantum systems. However, large molecular permanent electric dipole moments are challenging to realize experimentally. We report the observation of ultralong-range Rydberg molecules with bond lengths of ~100 nanometers and kilo-Debye permanent electric dipole moments that form when an ultracold ground-state cesium (Cs) atom becomes bound within the electronic cloud of an extended Cs electronic orbit. The electronic character of this hybrid class of "trilobite" molecules is dominated by degenerate Rydberg manifolds, making them difficult to produce by conventional photoassociation. We used detailed coupled-channel calculations to reproduce their properties quantitatively. Our findings may lead to progress in ultracold chemistry and strongly correlated many-body physics. PMID:25838380

Booth, D; Rittenhouse, S T; Yang, J; Sadeghpour, H R; Shaffer, J P

2015-04-01

328

Unraveling models of CP violation through electric dipole moments of light nuclei

We show that the proposed measurements of the electric dipole moments of light nuclei in storage rings would put strong constraints on models of flavor-diagonal CP violation. Our analysis is exemplified by a comparison of the Standard Model including the QCD theta term, the minimal left-right symmetric model, a specific version of the so-called aligned two-Higgs doublet model, and briefly the minimal supersymmetric extension of the Standard Model. By using effective field theory techniques we demonstrate to what extend measurements of the electric dipole moments of the nucleons, the deuteron, and helion could discriminate between these scenarios. We discuss how measurements of electric dipole moments of other systems relate to the light-nuclear measurements.

W. Dekens; J. de Vries; J. Bsaisou; W. Bernreuther; C. Hanhart; Ulf-G. Meißner; A. Nogga; A. Wirzba

2014-07-21

329

Electric Transition Dipole Moment in pre-Born-Oppenheimer Molecular Structure Theory

This paper presents the calculation of the electric transition dipole moment in a pre-Born-Oppenheimer framework. Electrons and nuclei are treated equally in terms of the parametrization of the non-relativistic total wave function, which is written as a linear combination of basis functions constructed with explicitly correlated Gaussian functions and the global vector representation. The integrals of the electric transition dipole moment are derived corresponding to these basis functions in both the length and the velocity representation. The complete derivation and the calculations are performed in laboratory-fixed Cartesian coordinates without relying on coordinates which separate the center of mass from the translationally invariant degrees of freedom. The effect of the overall motion is eliminated via translationally invariant integral expressions. As a numerical example the electric transition dipole moment is calculated between two rovibronic levels of the H2 molecule assignable to the lowest rovibrati...

Simmen, Benjamin; Reiher, Markus

2014-01-01

330

Self-energy anomaly of an electric pointlike dipole in three-dimensional static spacetimes

We calculate the self-energy anomaly of a pointlike electric dipole located in a static $(2+1)$-dimensional curved spacetime. The energy functional for this problem is invariant under an infinite-dimensional (gauge) group of transformations parameterized by one scalar function of two variables. We demonstrate that the problem of the calculation of the self-energy anomaly for a pointlike dipole can be reduced to the calculation of quantum fluctuations of an effective two-dimensional Euclidean quantum field theory. We reduced the problem in question to the calculation of the conformal anomaly of an effective scalar field in two dimensions and obtained an explicit expression for the self-energy anomaly of an electric dipole in an asymptotically flat, regular $(2+1)$-dimensional spacetime which may have electrically neutral black-hole-like metrics with regular Killing horizon.

Valeri P. Frolov; Andrey A. Shoom; Andrei Zelnikov

2013-03-07

331

Fabrication and test results of a Nb3Sn superconducting racetrack dipole magnet

A proof-of-principle Nb3Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets

K. Chow; D. R. Dietderich; S. A. Gourlay; R. Gupta; W. Harnden; A. F. Lietzke; A. D. McInturff; G. A. Millos; L. Morrison; R. M. Scanlan

1999-01-01

332

NSDL National Science Digital Library

SciGuides are a collection of thematically aligned lesson plans, simulations, and web-based resources for teachers to use with their students centered on standards-aligned science concepts. People have known about and experienced electricity an

2010-02-10

333

... conventional power sources, such as power lines, electrical substations, or home appliances. While some of these studies ... about EMFs emitted by a power line or substation in your area, you can contact your local ...

334

A Ten-Fold Improvement to the Limit of the Electron Electric Dipole Moment

NASA Astrophysics Data System (ADS)

The Standard Model of particle physics is wonderfully successful in its predictions but known to be incomplete. It fails to explain the existence of dark matter, and the fact that a universe made of matter survived annihilation with antimatter following the big bang. Extensions to the Standard Model, such as weak-scale Supersymmetry, provide explanations for some of these phenomena by asserting the existence of new particles and new interactions that break symmetry under time-reversal. These theories predict a small, yet potentially measurable electron electric dipole moment (EDM), de, that also violates time-reversal symmetry. Here, we report a new measurement of the electron EDM in the polar molecule thorium monoxide (ThO): de = -2.1 pm 3.7stat pm 2.5syst x 10-29 e cm, which corresponds to an upper limit of de| < 8.7 x 10 -29 e cm with 90 % confidence. This is more than an order of magnitude improvement in sensitivity compared to the previous limit. This result sets strong constraints on new physics at an energy scale (TeV) at least as high as that directly probed by the Large Hadron Collider. The unprecedented precision of this EDM measurement was achieved by using the high effective electric field within ThO to greatly magnify the EDM signal. Valence electrons travel relativistically near the heavy thorium nucleus and experience an effective electric field of about 100 GV/cm, millions of times larger than any static laboratory field. The reported measurement is a combination of millions of separate EDM measurements performed with billions of ThO molecules in a cold, slow buffer gas beam. Other features of ThO, such as a near-zero magnetic moment and high electric polarizability, allow potential systematic errors to be drastically suppressed and ensure the accuracy of our measurement.

Spaun, Benjamin Norman

335

Meson exchange current effects on magnetic dipole moments of p -shell nuclei

It is shown that addition of a two-body magnetic dipole operator arising from the exchange of the isovector pion and rho meson to the well-known one-body operator can give important corrections to the magnetic dipole moments of the {ital A}=4--16 nuclei. We performed shell-model calculations in complete 0{h bar}{omega} and (0+2){h bar}{omega} model spaces, thus investigating simultaneously the effects of extension of the model space and meson exchange currents on the magnetic moments. In the enlarged model space a significant improvement on the description of the magnetic moments is obtained by including exchange currents.

Booten, J.G.L.; van Hees, A.G.M.; Glaudemans, P.W.M. (Department of Physics and Astronomy, University of Utrecht, P.O. Box 80.000, 3508TA Utrecht, (Netherlands)); Wervelman, R. (Fundamenteel Onderzoek der Materie/Energieonderzoek Centrum Nederland Nuclear Structure Group, Netherlands Energy Research Foundation, P.O. Box 1, 1755 ZG Petten (Netherlands))

1991-01-01

336

Measurements of passive correction of magnetization higher multipoles in one meter long dipoles

The use of passive superconductor to correct the magnetization sextupole and decapole in SSC dipoles appears to be promising. This paper presents the results of a series of experiments of passive superconductor correctors in one meter long dipole magnets. Reduction of the magnetization sextupole by a factor of five to ten has been achieved using the passive superconductor correctors. The magnetization decapole was also reduced. The passive superconductor correctors reduced the sextupole temperature sensitivity by an order of magnitude. Flux creep decay was partially compensated for by the correctors. 13 refs., 7 figs.

Green, M.A.; Althaus, R.F.; Barale, P.J.; Benjegerdes, R.W.; Gilbert, W.S.; Green, M.I.; Scanlan, R.M.; Taylor, C.E.

1990-09-01

337

A robust limit for the electric dipole moment of the electron

Electric dipole moments constitute a competitive method to search for new physics, being particularly sensitive to new CP-violating phases. Given the experimental and theoretical progress in this field and more generally in particle physics, the necessity for more reliable bounds than the ones usually employed emerges. We therefore propose an improved extraction of the electric dipole moment of the electron and the relevant coefficient of the electron-nucleon coupling, taking into account theoretical uncertainties and possible cancellations, to be used in model-dependent analyses. Specifically, we obtain at 95% C.L. |d_e|Francium.

Martin Jung

2013-01-22

338

A robust limit for the electric dipole moment of the electron

Electric dipole moments constitute a competitive method to search for new physics, being particularly sensitive to new CP-violating phases. Given the experimental and theoretical progress in this field and more generally in particle physics, the necessity for more reliable bounds than the ones usually employed emerges. We therefore propose an improved extraction of the electric dipole moment of the electron and the relevant coefficient of the electron-nucleon coupling, taking into account theoretical uncertainties and possible cancellations, to be used in model-dependent analyses. Specifically, we obtain at 95% C.L. |d_e|Francium.

Jung, Martin

2013-01-01

339

b quark Electric Dipole moment in the general two Higgs Doublet and three Higgs Doublet models

We study the Electric Dipole moment of b quark in the general two Higgs Doublet model (model III) and three Higgs Doublet model with O(2) symmetry in the Higgs sector. We analyse the dependency of this quantity to the new phase coming from the complex Yukawa couplings and masses of charged and neutral Higgs bosons. We see that the Electric Dipole moment of b quark is at the order of 10^{-20} e cm, which is an extremely large value compared to one calculated in the SM and also two Higgs Doublet model (model II) with real Yukawa couplings.

E. O. Iltan

2001-05-17

340

P- and T-Violating Lagrangians in Chiral Effective Field Theory and Nuclear Electric Dipole Moments

A scheme to derive hadronic interactions induced by effective multi-quark terms is presented within the framework of chiral effective field theory. It is employed to work out the list of parity- and time-reversal-symmetry-violating hadronic interactions that are relevant for the computation of nuclear contributions to the electric dipole moments of the hydrogen-2, helium-3 and hydrogen-3 nuclei. We also derive the scattering and Faddeev equations required to compute electromagnetic form factors in general and electric dipole moments in particular.

J. Bsaisou; Ulf-G. Meißner; A. Nogga; A. Wirzba

2014-12-17

341

Polarity reversals and tilt of the Earth's magnetic dipole

NASA Technical Reports Server (NTRS)

There is evidence that the terrestrial magnetic field is connected with the Earth's mantle: (1) there are magnetic anomalies that do not take part in the westward drift of the main field, but are fixed with respect to the mantle; (2) the geomagnetic pole position flips in a particular way by preferred meridional paths during a reversal; and (3) magnetic polarity reversals are correlated with the activations of geological processes. These facts may be explained if we take into account that a significant horizontal temperature gradient can exist in the top levels of the liquid core because of the different thermoconductivity of the different areas of the core-mantle boundary. These temperature inhomogeneities can penetrate the core because fluxes along the core boundary (the thermal wind) can be strongly suppressed by a small redistribution of the chemical composition in the top of the core. The nonparallel gradients of the temperature, density, and composition on the top of the core create a curled electric field that produces a current and a magnetic field. This seed-field can be amplified by motions in the core. The resulting field does not forget the seed-field distribution and in this way the field on the Earth surface (that can be created only in regions with high conductivity, i.e. in the core) is connected with the core-mantle boundary. Contrary to the usual approach to the dynamo problem, we will take into account that the seed field of thermoelectric origin is acting not only at some initial moment of time but permanently.

Dolginov, A. Z.

1993-01-01

342

A robust limit for the electric dipole moment of the electron

NASA Astrophysics Data System (ADS)

Electric dipole moments constitute a competitive method to search for new physics, being particularly sensitive to new CP -violating phases. Given the experimental and theoretical progress in this field and more generally in particle physics, the necessity for more reliable bounds than the ones usually employed emerges. We therefore propose an improved extraction of the electric dipole moment of the electron and the relevant coefficient of the electron-nucleon coupling, taking into account theoretical uncertainties and possible cancellations, to be used in model-dependent analyses. Specifically, we obtain at 95% C.L. | d e | ? 0.14 × 10-26 e cm with present data, which is very similar to the bound typically quoted from the YbF molecule, but obtained in a more conservative manner. We examine furthermore in detail the prospects for improvements and derive upper limits for the dipole moments of several paramagnetic systems presently under investigation, i.e. cesium, rubidium and francium.

Jung, Martin

2013-05-01

343

Proposal for a cryogenic magnetic field measurement system for SSC dipole magnets

This proposal describes the research and development required, and the subsequent fabrication of, a system capable of making integrated magnetic multipole measurements of cryogenic 40-mm-bore SSC dipole magnets utilizing a cryogenic probe. Our experience and some preliminary studies indicate that it is highly unlikely that a 16-meter-long probe can be fabricated that will have a twist below several milliradians at cryogenic temperatures. We would anticipate a twist of several milliradians just as a result of cooldown stresses. Consequently, this proposal describes a segmented 16-meter-long probe, for which we intend to calibrate the phase of each segment to within 0.1 milliradians. The data for all segments will be acquired simultaneously, and integrated data will be generated from the vector sums of the individual segments. The calibration techniques and instrumentation required to implement this system will be described. The duration of an integral measurement at one current is expected to be under 10 seconds. The system is based on an extrapolation of the techniques used at LBL to measure cryogenic 1-meter models of SSC magnets with a cryogenic probe. It should be noted that the expansion of the dipole bore from 40 to 50 mm may make a warm-finger device practical at a cost of approximately one quarter of the cryogenic probe. A warm quadrupole measurement system can be based upon the same principles. 5 refs., 9 figs., 1 tab.

Green, M.I.; Hansen, L.

1991-03-01

344

Neutron electric dipole moment with external electric field method in lattice QCD

We discuss a possibility that the Neutron Electric Dipole Moment (NEDM) can be calculated in lattice QCD simulations in the presence of the CP violating $\\theta$ term. In this paper we measure the energy difference between spin-up and spin-down states of the neutron in the presence of an uniform and static external electric field. We first test this method in quenched QCD with the RG improved gauge action on a $16^3\\times 32$ lattice at $a^{-1}\\simeq$ 2 GeV, employing two different lattice fermion formulations, the domain-wall fermion and the clover fermion for quarks, at relatively heavy quark mass $(m_{PS}/m_V \\simeq 0.85)$. We obtain non-zero values of NEDM from calculations with both fermion formulations. We next consider some systematic uncertainties of our method for NEDM, using $24^3\\times 32$ lattice at the same lattice spacing only with the clover fermion. We finally investigate the quark mass dependence of NEDM and observe a non-vanishing behavior of NEDM toward the chiral limit. We interpret this behavior as a manifestation of the pathology in the quenched approximation.

E. Shintani; S. Aoki; N. Ishizuka; K. Kanaya; Y. Kikukawa; Y. Kuramashi; M. Okawa; A. Ukawa; T. Yoshié

2007-02-24

345

Reversals of the solar magnetic dipole in the light of observational data and simple dynamo models

NASA Astrophysics Data System (ADS)

Context. Observations show that the photospheric solar magnetic dipole usually does not vanish during the reversal of the solar magnetic field, which occurs in each solar cycle. In contrast, mean-field solar dynamo models predict that the dipole field does become zero. In a recent paper it was suggested that this contradiction could be explained as a large-scale manifestation of small-scale magnetic fluctuations of the surface poloidal field. Aims: Our aim is to confront this interpretation with the available observational data. Methods: Here we compare this interpretation with Wilcox Solar Observatory (WSO) photospheric magnetic field data in order to determine the amplitude of magnetic fluctuations required to explain the phenomenon and to compare the results with predictions from a simple dynamo model which takes these fluctuations into account. Results: We demonstrate that the WSO data concerning the magnetic dipole reversals are very similar to the predictions from our very simple solar dynamo model, which includes both mean magnetic field and fluctuations. The ratio between the rms value of the magnetic fluctuations and the mean field is estimated to be about 2, in reasonable agreement with estimates from sunspot data. The reversal epoch, during which the fluctuating contribution to the dipole is larger than that from the mean field, is about 4 months. The memory time of the fluctuations is about 2 months. Observations demonstrate that the rms of the magnetic fluctuations is strongly modulated by the phase of the solar cycle. This gives additional support to the concept that the solar magnetic field is generated by a single dynamo mechanism rather than also by independent small-scale dynamo action. A suggestion of a weak nonaxisymmetric magnetic field of a fluctuating nature arises from the analysis, with a lifetime of about 1 year. Conclusions: The behaviour of the magnetic dipole during the reversal epoch gives valuable information about details of solar dynamo action.

Pipin, V. V.; Moss, D.; Sokoloff, D.; Hoeksema, J. T.

2014-07-01

346

Schiff Theorem and the Electric Dipole Moments of Hydrogen-Like Atoms

The Schiff theorem is revisited in this work and the residual $P$- and $T$-odd electron--nucleus interaction, after the shielding takes effect, is completely specified. An application is made to the electric dipole moments of hydrogen-like atoms, whose qualitative features and systematics have important implication for realistic paramagnetic atoms.

C. -P. Liu; W. C. Haxton; M. J. Ramsey-Musolf; R. G. E. Timmermans; A. E. L. Dieperink

2006-01-09

347

Search for a permanent electric-dipole moment using atomic indium

We propose indium (In) as a possible candidate for observing the permanent electric dipole moment (EDM) arising from violations of parity (P) and time-reversal (T) symmetries. This atom has been laser cooled and therefore the measurement of its EDM has the potential of improving on the current best EDM limit for a paramagnetic atom, which comes from thallium. We report

B. K. Sahoo; R. Pandey; B. P. Das

2011-01-01

348

Energies, transition rates, and electron electric dipole moment (EDM) enhancement factors are calculated for low-lying states of Ce IV and Pr V using relativistic many-body perturbation theory. This study is related to recent investigations of the more complicated Gd IV ion, which is promising for electron EDM experiments. The ions Ce IV and Pr V both have a single valence

I. M. Savukov; W. R. Johnson; U. I. Safronova; M. S. Safronova

2003-01-01

349

The electron electric dipole moment enhancement factors of Rubidium and Caesium atoms

The enhancement factors of the electric dipole moment (EDM) of the ground states of two paramagnetic atoms; rubidium (Rb) and caesium (Cs) which are sensitive to the electron EDM are computed using the relativistic coupled-cluster theory and our results are compared with the available calculations and measurements. The possibility of improving the limit for the electron EDM using the results

H. S. Nataraj; B. K. Sahoo; B. P. Das; R. K. Chaudhuri; D. Mukherjee

2007-01-01

350

Enhancement factor for the electron electric dipole moment in francium and gold atoms

If electrons had an electric dipole moment (EDM) they would induce EDM's of atoms. The ratio of the atomic EDM to the electron EDM for a particular atom is called the enhancement factor R. We calculate the enhancement factor for the francium and gold atoms, with the results 910+\\/-~5% for Fr and 260+\\/-~15% for Au. The large values of these

T. M. R. Byrnes; V. A. Dzuba; V. V. Flambaum; D. W. Murray

1999-01-01

351

Electric Dipole Moment Enhancement Factor of Thallium S. G. Porsev,1,2

electron EDM, de electron EDM is enhanced in certain atomic and molecular systems, and two of the most stringent limits on the electron EDM of the electric dipole moment (EDM) enhancement factor of Tl. We carry out several calculations by different high

Safronova, Marianna

352

MCDHF calculations of the electric dipole moment of radium induced by the nuclear Schiff moment

The multiconfiguration Dirac-Hartree-Fock theory (MCDHF) has been employed to calculate the electric dipole moment of the 7s6d 3D2 state of radium induced by the nuclear Schiff moment. The results are dominated by valence and core-valence electron correlation effects. We show that the correlation effects can be evaluated in a converged series of multiconfiguration expansions.

Bieron, Jacek; Gaidamauskas, Erikas; Fritzsche, Sephan; Indelicato, Paul; Jönsson, Per

2009-01-01

353

The neutron Electric Dipole Moment experiment at the Paul Scherrer Institute

NASA Astrophysics Data System (ADS)

The neutron Electric Dipole Moment (nEDM) is a probe for physics beyond the Standard Model. A report on the nEDM measurement performed at the Paul Scherrer Institute (Switzerland) is given. A neutron spin analyzer designed to simultaneously detect both neutron spin states is presented.

Hélaine, V.

2014-06-01

354

Bipolar and unipolar tests of 1. 5m model SSC collider dipole magnets at Fermilab

Tests have been performed at Fermilab on 1.5 m magnetic length model SSC collider dipoles using both bipolar and unipolar ramp cycles. Hysteresis energy loss due to superconductor and iron magnetization and eddy currents is measured and compared as a function of various ramp parameters. Additionally, magnetic field measurements have been performed for both unipolar and bipolar ramp cycles. Measurements such as these will be used to estimate the heat load during collider injection for the SSC High Energy Booster dipoles. 9 refs., 4 figs.

Lamm, M.J.; Ozelis, J.P.; Coulter, K.J.; Delchamps, S.; Jaffery, T.S.; Kinney, W.; Koska, W.; Strait, J.; Wake, M. (Fermi National Accelerator Lab., Batavia, IL (USA)); Fortunato, D.; Johnson, D.E. (Superconducting Super Collider Lab., Dallas, TX (USA))

1991-05-01

355

Electric and Magnetic Forces: Electromagnetism

NSDL National Science Digital Library

Science Objects are two hour on-line interactive inquiry-based content modules that help teachers better understand the science content they teach.This Science Object is the last of three Science Objects in the Electric and Magnetic Forces SciPack.

National Science Teachers Association (NSTA)

2008-10-30

356

Ground State and Collective Modes of Magnetic Dipoles Fixed on Two-Dimensional Lattice Sites

NASA Astrophysics Data System (ADS)

In complex (dusty) plasmas the grains may be endowed with intrinsic dipole moments. We present here our results of theoretical calculations accompanied by and Molecular Dynamics simulation findings on the ground state configuration and on the collective modes mode spectrum of a system of magnetic dipoles, interacting via the magnetic dipole pair-dipole potential, fixed on two-dimensional (2D) lattice sites. In particular, we We study a family of lattices that can be characterized by two parameters: (parallelogram)---the aspect ratio, c/a, and the rhombic angle, phi. The The new collective modes of in the system associated with the dipole-dipole interaction are the angular oscillations (or wobbling) of the direction of the dipoles about their equilibrium configurations. We identify in-plane and out-of-plane modes and display their dispersions. Orders of magnitudes of the parameters of the system relevant to possible future experiments will be discussed. JD Feldmann, G J Kalman and M Rosenberg, J. Phys. A: Math. Gen. 39 (2006) 4549-4553

Feldmann, John; Kalman, Gabor; Hartmann, Peter; Rosenberg, Marlene

2006-10-01

357

Design and Test of a Nb3Sn Subscale Dipole Magnet for Training Studies

As part of a collaboration between CEA/Saclay and the Superconducting Magnet Group at LBNL, a subscale dipole structure has been developed to study training in Nb3Sn coils under variable pre-stress conditions. This design is derived from the LBNL Subscale Magnet and relies on the use of identical Nb{sub 3}Sn racetrack coils. Whereas the original LBNL subscale magnet was in a dual bore 'common-coil' configuration, the new subscale dipole magnet (SD) is assembled as a single bore dipole made of two superposed racetrack coils. The dipole is supported by a new mechanical structure developed to withstand the horizontal and axial Lorentz forces and capable of applying variable vertical, horizontal and axial preload. The magnet was tested at LBNL as part of a series of training studies aiming at understanding of the relation between pre-stress and magnet performance. Particular attention is given to the coil ends where the magnetic field peaks and stress conditions are the least understood. After a description of SD design, assembly, cool-down and tests results are reported and compared with the computations of the OPERA3D and ANSYS magnetic and mechanical models.

Felice, Helene; Caspi, Shlomo; Dietderich, Daniel R.; Felice, Helene; Ferracin, Paolo; Gourlay, Steve A.; Hafalia, Aurelo R.; Lietzke, Alan F.; Mailfert, Alain; Sabbi, GainLuca; Vedrine, Pierre

2007-06-01

358

Quench performance of 50-mm aperture, 15-m-long SSC dipole magnets built at Fermilab

The quench performance, ramp rate dependence, and mechanical behavior of ten full-length, 50-mm-aperture, SSC dipole magnets built at Fermilab are discussed. Cold testing of these magnets shows that the quench plateau established at 4.35 K exceeds the design value by more than 10%, virtually without training.

Kuzminski, J.; Bush, T.; Coombes, R. [and others

1992-07-01

359

The superconducting dipole prototype magnet of the collector ring for the Facility for Antiproton and Ion Research (FAIR) is an international cooperation project. The collaborative simulation and testing of the developed prototype magnet is presented in this paper. To evaluate the mechanical strength of the coil case during quench, a 3-dimensional (3D) electromagnetic (EM) model was developed based on the

Zhu Yinfeng; Zhu Zhe; Xu Houchang; Wu Weiyue

2012-01-01

360

Hysteresis of sextupole and ac loss in Energy Doubler dipole magnets

A simple model gave utilized for calculation of magnetization effects on ac loss and sextupole for Energy Doubler dipole magnets. The calculation in the simple model gave an underestimation of ac loss by about 30%. Results of computation on ac harmonics were also described.

Ishibashi, K.

1982-06-18

361

Lifetime of an emitting dipole near various types of interfaces including magnetic and negative known case of metallic reflectors, but also to magnetic reflectors and to negative refractive index.1063/1.1812742 I. INTRODUCTION The modification of molecular fluorescence near a metal surface has been the subject

Floreano, Dario

362

Anisotropy of magnetic emulsions induced by magnetic and electric fields

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.

Yury I. Dikansky; Alexander N. Tyatyushkin; Arthur R. Zakinyan

2011-09-10

363

A Storage Ring Experiment to Detect a Proton Electric Dipole Moment

A new experiment is described to detect a permanent electric dipole moment of the proton with a sensitivity of $10^{-29}e\\cdot$cm by using polarized "magic" momentum $0.7$~GeV/c protons in an all-electric storage ring. Systematic errors relevant to the experiment are discussed and techniques to address them are presented. The measurement is sensitive to new physics beyond the Standard Model at the scale of 3000~TeV.

V. Anastassopoulos; S. Andrianov; R. Baartman; M. Bai; S. Baessler; J. Benante; M. Berz; M. Blaskiewicz; T. Bowcock; K. Brown; B. Casey; M. Conte; J. Crnkovic; G. Fanourakis; A. Fedotov; P. Fierlinger; W. Fischer; M. O. Gaisser; Y. Giomataris; M. Grosse-Perdekamp; G. Guidoboni; S. Haciomeroglu; G. Hoffstaetter; H. Huang; M. Incagli; A. Ivanov; D. Kawall; B. Khazin; Y. I. Kim; B. King; I. A. Koop; R. Larsen; D. M. Lazarus; V. Lebedev; M. J. Lee; S. Lee; Y. H. Lee; A. Lehrach; P. Lenisa; P. Levi Sandri; A. U. Luccio; A. Lyapin; W. MacKay; R. Maier; K. Makino; N. Malitsky; W. J. Marciano; W. Meng; F. Meot; E. M. Metodiev; L. Miceli; D. Moricciani; W. M. Morse; S. Nagaitsev; S. K. Nayak; Y. F. Orlov; C. S. Ozben; S. T. Park; A. Pesce; P. Pile; V. Polychronakos; B. Podobedov; J. Pretz; V. Ptitsyn; E. Ramberg; D. Raparia; F. Rathmann; S. Rescia; T. Roser; H. Kamal Sayed; Y. K. Semertzidis; Y. Senichev; A. Sidorin; A. Silenko; N. Simos; A. Stahl; E. J. Stephenson; H. Stroeher; M. J. Syphers; J. Talman; R. M. Talman; V. Tishchenko; C. Touramanis; N. Tsoupas; G. Venanzoni; K. Vetter; S. Vlassis; E. Won; G. Zavattini; A. Zelenski; K. Zioutas

2015-02-15

364

Measurement of the electron electric dipole moment using GdIG

A new method for the detection of the electron edm using a solid is\\u000adescribed. The method involves the measurement of a voltage induced across the\\u000asolid by the alignment of the samples magnetic dipoles in an applied magnetic\\u000afield, H. A first application of the method to GdIG has resulted in a limit on\\u000athe electron edm of 5E-24

B. J. Heidenreich; O. T. Elliott; N. D. Charney; K. A. Virgien; A. W. Bridges; S. K. Lamoreaux; S. K. Peck; D. Krause; J. E. Gordon; L. R. Hunter

2005-01-01

365

NASA Technical Reports Server (NTRS)

The acquisition of thermoremanent magnetization (TRM) by a cooling spherical shell is studied for internal magnetizing dipole fields, using Runcorn's (1975) theorems on magnetostatics. If the shell cools progressively inward, inner regions acquire TRM in a net field composed of the dipole source term plus a uniform field due to the outer magnetized layers. In this case, the global dipole moment and external remanent field are nonzero when the whole shell has cooled below the Curie point and the source dipole has disappeared. The remanent field outside the shell is found to depend on the thickness, radii, and cooling rate of the shell, as well as the coefficient of TRM and the intensity of the magnetizing field. Some implications for the moon's remanent dipole moment are discussed.

Srnka, L. J.

1976-01-01

366

Electric Dipole Moments Do Not Require the CP-violating Phases of Supersymmetry To Be Small

We report the first fully general numerical calculation of the neutron and electron dipole moments, including the seven significant phases. We find that there are major regions in the parameter space where none of the phases are required to be small, contrary to the conventional wisdom. The electric dipole moments (EDM's) do provide useful constraints, allowing other regions of parameter space to be carved away. We keep all superpartner masses light so agreement with experimental limits arises purely from interesting relations among soft breaking parameters.

Michal Brhlik; Gerald J. Good; G. L. Kane

1998-11-02

367

Theoretical study of the electric dipole moment function of the ClO molecule

NASA Technical Reports Server (NTRS)

The potential energy function and electric dipole moment function (EDMF) are computed for ClO X 2Pi using several different techniques to include electron correlation. The EDMF is used to compute Einstein coefficients, vibrational lifetimes, and dipole moments in higher vibrational levels. The band strength of the 1-0 fundamental transition is computed to be 12 + or - 2 per sq cm atm determined from infrared heterodyne spectroscopy. The theoretical methods used include SCF, CASSCF, multireference singles plus doubles configuration interaction (MRCI) and contracted CI, coupled pair functional (CPF), and a modified version of the CPF method. The results obtained using the different methods are critically compared.

Pettersson, L. G. M.; Langhoff, S. R.; Chong, D. P.

1986-01-01

368

Electric and Magnetic Walls on Dielectric Interfaces

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.

Changbiao Wang

2010-07-20

369

The relativistic coupled-cluster method is applied to calculate the magnetic dipole hyperfine constant 'A' of the 6s{sub 1/2}, 6p{sub 1/2}, 6p{sub 3/2}, and 5d{sub 3/2} states of singly ionized barium. After the inclusion of two-body correlation effects into the computation of the hyperfine matrix elements, the accuracy of the obtained values was significantly increased compared to earlier computations. Based on these numbers and earlier calculations of the electric dipole transitions and excitation energies, an estimate for the accuracy of the vertical bar [5p{sup 6}]6s{sub 1/2}>{yields} vertical bar [5p{sup 6}]5d{sub 3/2}> parity-nonconserving electric dipole transition amplitude is carried out. The results suggest that for the first time, to our knowledge, a precision of better than 1% is feasible for this transition amplitude.

Sahoo, Bijaya K.; Gopakumar, Geetha; Chaudhuri, Rajat K.; Das, B.P.; Merlitz, Holger; Mahapatra, Uttam Sinha; Mukherjee, Debashis [Non-Accelerator Particle Physics Group, Indian Institute of Astrophysics, Bangalore 560034 (India); Forschungszentrum Karlsruhe GmbH, Institut fuer Nanotechnologie, Postfach 3640, D-76021 Karlsruhe (Germany); Department of Physical Chemistry, Indian Association for Cultivation of Science, Calcutta 700 032 (India)

2003-10-01

370

Comparison between active and passive shielding magnets for a large acceptance superconducting dipole magnet has been carried out. The two magnet designs have been studied to answer to the new requirements of Nuclear Physics experiments in order to get a momentum resolution of up to 10-3 with 1 GeV\\/nucleon heavy-ion beams: A field integral of about 5Tmiddotm

Bernard Gastineau; Chhon Pes; Jean-Eric Ducret

2006-01-01

371

Electric dipole response of $^6$He: Halo-neutron and core excitations

Electric dipole ($E1$) response of $^{6}$He is studied with a fully microscopic six-body calculation. The wave functions for the ground and excited states are expressed as a superposition of explicitly correlated Gaussians (CG). Final state interactions of three-body decay channels are explicitly taken into account. The ground state properties and the low-energy $E1$ strength are obtained consistently with observations. Two main peaks as well as several small peaks are found in the $E1$ strength function. The peak at the high-energy region indicates a typical macroscopic picture of the giant dipole resonance, the out-of-phase proton-neutron motion. The transition densities of the lower-lying peaks exhibit in-phase proton-neutron motion in the internal region, out-of-phase motion near the surface region, and spatially extended neutron oscillation, indicating a soft-dipole mode (SDM) and its vibrationally excited mode.

D. Mikami; W. Horiuchi; Y. Suzuki

2014-05-24

372

Measurement of net electric charge and dipole moment of dust aggregates in a complex plasma.

Understanding the agglomeration of dust particles in complex plasmas requires knowledge of basic properties such as the net electrostatic charge and dipole moment of the dust. In this study, dust aggregates are formed from gold-coated mono-disperse spherical melamine-formaldehyde monomers in a radiofrequency (rf) argon discharge plasma. The behavior of observed dust aggregates is analyzed both by studying the particle trajectories and by employing computer models examining three-dimensional structures of aggregates and their interactions and rotations as induced by torques arising from their dipole moments. These allow the basic characteristics of the dust aggregates, such as the electrostatic charge and dipole moment, as well as the external electric field, to be determined. It is shown that the experimental results support the predicted values from computer models for aggregates in these environments. PMID:25314541

Yousefi, Razieh; Davis, Allen B; Carmona-Reyes, Jorge; Matthews, Lorin S; Hyde, Truell W

2014-09-01

373

Measurement of net electric charge and dipole moment of dust aggregates in a complex plasma

NASA Astrophysics Data System (ADS)

Understanding the agglomeration of dust particles in complex plasmas requires knowledge of basic properties such as the net electrostatic charge and dipole moment of the dust. In this study, dust aggregates are formed from gold-coated mono-disperse spherical melamine-formaldehyde monomers in a radiofrequency (rf) argon discharge plasma. The behavior of observed dust aggregates is analyzed both by studying the particle trajectories and by employing computer models examining three-dimensional structures of aggregates and their interactions and rotations as induced by torques arising from their dipole moments. These allow the basic characteristics of the dust aggregates, such as the electrostatic charge and dipole moment, as well as the external electric field, to be determined. It is shown that the experimental results support the predicted values from computer models for aggregates in these environments.

Yousefi, Razieh; Davis, Allen B.; Carmona-Reyes, Jorge; Matthews, Lorin S.; Hyde, Truell W.

2014-09-01

374

Theoretical Study of the Electric Dipole Moment Function of the CIO Molecule

NASA Technical Reports Server (NTRS)

The potential energy function and electric dipole moment function (EDMF) are computed for CIO Chi(sup 2)Pi using several different techniques to include electron correlation. The EDMF is used to compute Einstein coefficients, vibrational lifetimes, and dipole moments in higher vibrational levels. Remaining questions concerning the position of the maximum of the EDMF may be resolved through experimental measurement of dipole moments of higher vibrational levels. The band strength of the 1-0 fundamental transition is computed to be 12 +/- 2 /sq cm atm in good agreement with three experimental values, but larger than a recent value of 5 /sq cm atm determined from infrared heterodyne spectroscopy. The theoretical methods used include SCF, CASSCF, multireference singles plus doubles configuration interaction (MRCI) and contracted CI, coupled pair functional (CPF), and a modified version of the CPF method. The results obtained using the different methods are critically compared.

Pettersson, Lars G. M.; Langhoff, Stephen R.; Chong, Delano P.

1986-01-01

375

Radiation effects in a muon collider ring and dipole magnet protection

The requirements and operating conditions for a Muon Collider Storage Ring (MCSR) pose significant challenges to superconducting magnets. The dipole magnets should provide a high magnetic field to reduce the ring circumference and thus maximize the number of muon collisions during their lifetime. One third of the beam energy is continuously deposited along the lattice by the decay electrons at the rate of 0.5 kW/m for a 1.5-TeV c.o.m. and a luminosity of 10{sup 34} cm{sup -2}s{sup -1}. Unlike dipoles in proton machines, the MCSR dipoles should allow this dynamic heat load to escape the magnet helium volume in the horizontal plane, predominantly towards the ring center. This paper presents the analysis and comparison of radiation effects in MCSR based on two dipole magnets designs. Tungsten masks in the interconnect regions are used in both cases to mitigate the unprecedented dynamic heat deposition and radiation in the magnet coils.

Mokhov, N.V.; Kashikhin, V.V.; Novitski, I.; Zlobin, A.V.; /Fermilab

2011-03-01

376

Improvements in the Berkeley electron electric dipole moment experiment

Changes will be made in the Berkeley electron EDM experiment, resulting in major reductions of noise and elimination of the most important systematic effects, and leading to a precision of better than 10âğÂ²â¸ e-cm In the determination of the electron EDM d{sub e}. We now use atomic beams of thallium in the 6Pââ, F=1 state in a uniform magnetic field

D. Demille; E. D. Cummins

1993-01-01

377

On Measuring the Electron Electric Dipole Moment in Trapped Molecular Ions

Trapped diatomic molecular ions could prove to be a sensitive probe for a permanent electron electric dipole moment (eEDM). We propose to use a ground or metastable $^3\\Delta_1$ level, due to its high polarizability and large EDM enhancement factor. Ions allow for simple trapping and long interrogation times, but require a time-varying electric bias field in order to probe the eEDM. We discuss experimental design as well as challenges in performing a precision spectroscopic measurement in rapidly time-varying electric fields.

Leanhardt, Aaron E; Loh, Huanqian; Maletinsky, Patrick; Meyer, Edmund R; Sinclair, Laura C; Stutz, Russell P; Cornell, Eric A

2010-01-01

378

Molecular Expressions: Electricity & Magnetism: Resistance

NSDL National Science Digital Library

Comprehensive tutorial on resistance, accompanied by three interactive simulations. One allows the user to glimpse resistance at a molecular level; the second explores Ohm's Law; and the third introduces the use of color coding in composition resistors. The author uses diagrams to illustrate arrangements of resistors in series and parallel circuits, with explanations of how to calculate equivalent resistances. This item is part of a larger collection on Electricity and Magnetism sponsored by Florida State University..

Michael Davidson

379

A discovery of a permanent electric dipole moment (EDM) of the neutron would provide one of the most important low energy tests of the discrete symmetries beyond the Standard Model of particle physics. A new search of neutron EDM, to be conducted at the spallation neutron source (SNS) at ORNL, is designed to improve the present experimental limit of ~10^-26 e-cm by two orders of magnitude. The experiment is based on the magnetic-resonance technique in which polarized neutrons precess at the Larmor frequency when placed in a static magnetic field; a non-zero EDM would be evident as a difference in precession frequency when a strong external electric field is applied parallel vs. anti-parallel to the magnetic field. In addition to its role as neutron spin-analyzer via the spin-dependent n+3He nuclear capture reaction, polarized helium-3 (which has negligible EDM) will serve as co-magnetometer to correct for drifts in the magnetic field. In one of the two methods that will be built into the apparatus, the helium-3 precession signal is read out by SQUID-based gradiometers. We present a design study of a SQUID system suitable for the neutron EDM apparatus, and discuss using very long leads between the pickup loop and the SQUID.

Young Jin Kim; Steven M. Clayton

2012-10-17

380

A discovery of a permanent electric dipole moment (EDM) of the neutron would provide one of the most important low energy tests of the discrete symmetries beyond the Standard Model of particle physics. A new search of neutron EDM, to be conducted at the spallation neutron source (SNS) at ORNL, is designed to improve the present experimental limit of ~10^-26 e-cm by two orders of magnitude. The experiment is based on the magnetic-resonance technique in which polarized neutrons precess at the Larmor frequency when placed in a static magnetic field; a non-zero EDM would be evident as a difference in precession frequency when a strong external electric field is applied parallel vs. anti-parallel to the magnetic field. In addition to its role as neutron spin-analyzer via the spin-dependent n+3He nuclear capture reaction, polarized helium-3 (which has negligible EDM) will serve as co-magnetometer to correct for drifts in the magnetic field. In one of the two methods that will be built into the apparatus, the helium...

Kim, Young Jin

2012-01-01

381

We address a number of issues regarding solid state electron electric dipole moment (EDM) experiments, focusing on gadolinium iron garnet (abbreviated GdIG, chemical formula Gd$_3$Fe$_5$O$_{12}$) as a possible sample material. GdIG maintains its high magnetic susceptibility down to 4.2 K, which enhances the EDM-induced magnetization of a sample placed in an electric field. We estimate that lattice polarizability gives rise to an EDM enhancement factor of approximately 20. We also calculate the effect of the demagnetizing field for various sample geometries and permeabilities. Measurements of intrinsic GdIG magnetization noise are presented, and the fluctuation-dissipation theorem is used to compare our data with the measurements of the imaginary part of GdIG permeability at 4.2 K, showing good agreement above frequencies of a few hertz. We also observe how the demagnetizing field suppresses the noise-induced magnetic flux, confirming our calculations. The statistical sensitivity of an EDM search based on a so...

Sushkov, A O; Lamoreaux, S K

2008-01-01

382

Polarity Reversal Time of the Magnetic Dipole Component of the Sun in Solar Cycle 24

NASA Astrophysics Data System (ADS)

The Sun's general magnetic field has shown polarity reversal three times during the last three solar cycles. We attempt to estimate the upcoming polarity reversal time of the solar magnetic dipole by using the coronal field model and synoptic data of the photospheric magnetic field. The scalar magnetic potential of the coronal magnetic field is expanded into a spherical harmonic series. The long-term variations of the dipole component (g01) calculated from the data of National Solar Observatory/Kitt Peak and Wilcox Solar Observatory are compared with each other. It is found that the two g01 values show a similar tendency and an approximately linear increase between the Carrington rotation periods CR 2070 and CR 2118. The next polarity reversal is estimated by linear extrapolation to be between CR 2132.2 (December 2012) and CR2134.8 (March 2013).

Hakamada, Kazuyuki

2013-04-01

383

Tests of a 3 meter curved superconducting beam transport dipole magnet

Initial tests of one of the curved 3 m long superconducting dipole magnets intended to generate 6.0 T and produce a 20.4/sup 0/ bend in the primary proton beam to a new D-target station at the Brookhaven National Laboratory AGS have been completed. Although this magnet, whose window frame design generally follows that of the successful 8/sup 0/ and Model T superconducting dipoles, demonstrates many of the desirable characteristics of these earlier magnets such as excellent quench propagation and good ramping properties, it has only reached a disappointingly low magnetic field of 3.5 to 4.0 T. Because of the great interest in superconducting magnet technology, this report will describe the diagnostic tests performed and plans for future modifications.

Allinger, J E; Carroll, A S; Danby, G T; DeVito, B; Jackson, J W; Leonhardt, W J; Prodell, A G; Weisenbloom, J

1981-01-01

384

Motivated by arguments of the nuclear core-layer model formulated in [S.I. Bastrukov, J.A. Maruhn, Z.Phys. A 335 (1990) 139], the macroscopic excitation mechanism of electric pygmy dipole resonance (PDR) is considered as owing its origin to perturbation-induced effective decomposition of nucleus into two spherical domains - undisturbed inner region treated as static core and dynamical layer undergoing elastic shear vibrations. The focus is placed on the imprinted in the core-layer model mechanism of emergence of the low-energy dipole electric resonant excitation as Goldstone soft mode of translation layer-against-core oscillations. To accentuate this attitude we regain the obtained in the above paper spectral equation for the frequency of spheroidal elastic vibrations trapped in the finite-depth layer, but by working from canonical equation of elastic dynamics of continuous medium. The obtained analytic equations for the frequency of dipole vibrational state in question and its excitation strength exhibit fundamental character of this soft dipole mode of nuclear resonant response.

S. I. Bastrukov; I. V. Molodtsova; S. Misicu; H-K. Chang; D. V. Podgainy

2008-05-10

385

Observation of electric-dipole-forbidden infrared transitions in cold molecular ions

NASA Astrophysics Data System (ADS)

Spectroscopic transitions in atoms and molecules that are not allowed within the electric-dipole approximation, but occur because of higher-order terms in the interaction between matter and radiation, are termed dipole-forbidden. These transitions are extremely weak and therefore exhibit very small natural linewidths. Dipole-forbidden optical transitions in atoms form the basis of next-generation atomic clocks and of high-fidelity qubits used in quantum information processors and quantum simulators. In molecules, however, such transitions are much less characterized, reflecting the considerable challenges to address them. Here, we report direct observation of dipole-forbidden, electric-quadrupole-allowed infrared (IR) transitions in a molecular ion. Their detection was enabled by the very long interrogation times of several minutes afforded by the sympathetic cooling of individual quantum-state-selected molecular ions into the nearly perturbation-free environment of a Coulomb crystal. The present work paves the way for new mid-IR frequency standards and precision spectroscopic measurements on single molecules in the IR domain.

Germann, Matthias; Tong, Xin; Willitsch, Stefan

2014-11-01

386

Electric dipole (hyper)polarizabilities of spatially confined LiH molecule

NASA Astrophysics Data System (ADS)

In this study we report on the electronic contributions to the linear and nonlinear static electronic electric dipole properties, namely the dipole moment (?), the polarizability (?), and the first-hyperpolarizability (?), of spatially confined LiH molecule in its ground X 1?+ state. The finite-field technique is applied to estimate the corresponding energy and dipole moment derivatives with respect to external electric field. Various forms of confining potential, of either spherical or cylindrical symmetry, are included in the Hamiltonian in the form of one-electron operator. The computations are performed at several levels of approximation including the coupled-cluster methods as well as multi-configurational (full configuration interaction) and explicitly correlated Gaussian wavefunctions. The performance of Kohn-Sham density functional theory for the selected exchange-correlation functionals is also discussed. In general, the orbital compression effects lead to a substantial reduction in all the studied properties regardless of the symmetry of confining potential, however, the rate of this reduction varies depending on the type of applied potential. Only in the case of dipole moment under a cylindrical confinement a gradual increase of its magnitude is observed.

Góra, Robert W.; Zale?ny, Robert; Koz?owska, Justyna; Naci??ek, Paulina; Roztoczy?ska, Agnieszka; Strasburger, Krzysztof; Bartkowiak, Wojciech

2012-09-01

387

Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

A 'proof-of-principle' Nb{sub 3}Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets are expected to approach 15 Tesla with substantially improved conductor.

Chow, K.; Dietderich, D.R.; Gourlay, S.A.; Gupta, R.; Harnden, W.; Lietzke, A. F.; McInturff, A.D.; Millos, G.A.; Morrison, L.; Morrison, M.; Scanlan, R.M.

2000-02-06

388

Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

A 'proof-of-principle' Nb{sub 3}Sn superconducting dual-bore dipole magnet was built from racetrack coils, as a first step in a program to develop an economical, 15 Tesla, accelerator-quality magnet. The mechanical design and magnet fabrication procedures are discussed. No training was required to achieve temperature-dependent plateau currents, despite several thermal cycles that involved partial magnet disassembly and substantial pre-load variations. Subsequent magnets are expected to approach 15 Tesla with substantially improved conductor.

Chow, K.; Dietderich, D.R.; Gourlay, S.A.; Gupta, R.; Harnden, W.; Lietzke, A.F.; McInturff, A.D.; Millos, G.A.; Morrison, L.; Morrison, M.; Scanlan, R.M.

1999-03-22

389

We calculate the electric dipole moment of electron using the experimental result of muon electric dipole moment and upper limit of the BR(\\mu --> e\\gamma) in the framework of the general two Higgs doublet model. Our prediction is 10^{-32} e-cm, which lies in the experimental current limits. Further, we obtain constraints for the Yukawa couplings \\bar{\\xi}^{D}_{N,\\tau e} and \\bar{\\xi}^{D}_{N,\\tau\\mu}. Finally we present an expression which connects the BR(\\tau\\to \\mu\\gamma) and the electric dipole moment of \\tau-lepton and study the relation between these physical quantities.

E. O. Iltan

2001-05-17

390

Large tau and tau neutrino electric dipole moments in models with vectorlike multiplets

It is shown that the electric dipole moment of the {tau} lepton several orders of magnitude larger than predicted by the standard model can be generated from mixings in models with vectorlike mutiplets. The electric dipole moment (EDM) of the {tau} lepton arises from loops involving the exchange of the W, the charginos, the neutralinos, the sleptons, the mirror leptons, and the mirror sleptons. The EDM of the Dirac {tau} neutrino is also computed from loops involving the exchange of the W, the charginos, the mirror leptons, and the mirror sleptons. A numerical analysis is presented, and it is shown that the EDMs of the {tau} lepton and the {tau} neutrino which lie just a couple of orders of magnitude below the sensitivity of the current experiment can be achieved. Thus the predictions of the model are testable in an improved experiment on the EDM of the {tau} and the {tau} neutrino.

Ibrahim, Tarek [Department of Physics, Faculty of Science, University of Alexandria, Alexandria (Egypt); Department of Physics, Northeastern University, Boston, Massachusetts 02115-5000 (United States); Nath, Pran [Department of Physics, Northeastern University, Boston, Massachusetts 02115-5000 (United States)

2010-02-01

391

Probing CP violation with the electric dipole moment of atomic mercury

The electric dipole moment of atomic $^{199}$Hg induced by the nuclear Schiff moment and tensor-pseudotensor electron-nucleus interactions has been calculated. For this, we have developed and employed a novel method based on the relativistic coupled-cluster theory. The results of our theoretical calculations combined with the latest experimental result of $^{199}$Hg electric dipole moment, provide new bounds on the T reversal or CP violation parameters $\\theta_{\\rm QCD}$, the tensor-pseudotensor coupling constant $C_T$ and $(\\widetilde{d}_u - \\widetilde{d}_d)$. This is the most accurate calculation of these parameters to date. We highlight the the crucial role of electron correlation effects in their interplay with the P,T violating interactions. Our results demonstrate substantial changes in the results of earlier calculations of these parameters which can be attributed to the more accurate inclusion of important correlation effects in the present work.

K. V. P. Latha; D. Angom; B. P. Das; D. Mukherjee

2009-02-27

392

Operator evolution for ab initio electric dipole transitions of 4He

A goal of nuclear theory is to make quantitative predictions of low-energy nuclear observables starting from accurate microscopic internucleon forces. A major element of such an effort is applying unitary transformations to soften the nuclear Hamiltonian and hence accelerate the convergence of ab initio calculations as a function of the model space size. The consistent simultaneous transformation of external operators, however, has been overlooked in applications of the theory, particularly for nonscalar transitions. We study the evolution of the electric dipole operator in the framework of the similarity renormalization group method and apply the renormalized matrix elements to the calculation of the 4He total photoabsorption cross section and electric dipole polarizability. All observables are calculated within the ab initio no-core shell model. We find that, although seemingly small, the effects of evolved operators on the photoabsorption cross section are comparable in magnitude to the correction produced by including the chiral three-nucleon force and cannot be neglected.

Micah D. Schuster; Sofia Quaglioni; Calvin W. Johnson; Eric D. Jurgenson; Petr Navratil

2015-04-02

393

Torque for electron spin induced by electron permanent electric dipole moment

The spin torque of the electron is studied in relation to the electric dipole moment (EDM) of the electron. The spin dynamics is known to be given by the spin torque and the zeta force in quantum field theory. The effect of the EDM on the torque of the spin brings a new term in the equation of motion of the spin. We study this effect for a solution of the Dirac equation with electromagnetic field.

Senami, Masato, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Fukuda, Masahiro, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Ogiso, Yoji, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp; Tachibana, Akitomo, E-mail: senami@me.kyoto-u.ac.jp, E-mail: akitomo@scl.kyoto-u.ac.jp [Department of Micro Engineering, Kyoto University, Kyoto 615-8540 (Japan)

2014-10-06

394

We perform a comprehensive study of the dominant two- and higher-loop contributions to the 205Tl, neutron and muon electric dipole moments induced by Higgs bosons, third-generation quarks and squarks, charginos and gluinos in the Minimal Supersymmetric Standard Model (MSSM). We find that strong correlations exist among the contributing CP-violating operators, for large stop, gluino and chargino phases, and for a wide

Apostolos Pilaftsis

2002-01-01

395

Larger Higgs-boson-exchange terms in the neutron electric dipole moment

The neutron electric dipole moment (dn) due to Higgs-boson exchange is reconsidered, now without assuming that Higgs-boson exchange is solely responsible for K0L-->2pi. The dominant contribution to dn arises from a three-gluon operator, produced in integrating out top quarks and neutral Higgs bosons. The estimated results together with current experimental bounds on dn show, even for the largest plausible Higgs-boson

Steven Weinberg

1989-01-01

396

RESONANCE METHOD OF ELECTRIC-DIPOLE-MOMENT MEASUREMENTS IN STORAGE RINGS.

A ''resonance method'' of measuring the electric dipole moment (EDM) of nuclei in storage rings is described, based on two new ideas: (1) Oscillating particles velocities in resonance with spin precession, and (2) alternately producing two sub-beams with different betatron tunes--one sub-beam to amplify and thus make it easier to correct ring imperfections that produce false signals imitating EDM signals, and the other to make the EDM measurement.

ORLOV, Y.F.; MORSE, W.M.; SEMERTZIDIS, Y.K.

2006-05-10

397

Resonance Method of Electric-Dipole-Moment Measurements in Storage Rings

A 'resonance method' of measuring the electric dipole moment (EDM) of nuclei in storage rings is described, based on two new ideas: (1) Oscillating particles' velocities in resonance with spin precession, and (2) alternately producing two sub-beams with different betatron tunes--one sub-beam to amplify and thus make it easier to correct ring imperfections that produce false signals imitating EDM signals, and the other to make the EDM measurement.

Orlov, Yuri F. [Brookhaven National Laboratory, Upton, New York 11973 (United States); Laboratory for Elementary-Particle Physics, Cornell University, Ithaca New York 14853 (United States); Morse, William M.; Semertzidis, Yannis K. [Brookhaven National Laboratory, Upton, New York 11973 (United States)

2006-06-02

398

Neutron electric dipole moment and flavor changing interactions in supersymmetric theories

Supersymmetric contributions to the neutron electric dipole moment (EDM) are studied taking account of the flavor changing interactions. We found that the gluino contribution is sensitive to the flavor changing interaction. Enhancement of neutron EDM via flavor mixing effects is possible when the squark mass difference between the different generations is sizable. As an example, the results of the SUSY SU(5) GUT with right-handed neutrinos are briefly discussed.

Gi-Chol Cho; Naoyuki Haba; Minako Honda

2005-10-04

399

Motivated by arguments of the nuclear core-layer model formulated in [S.I. Bastrukov, J.A. Maruhn, Z. Phys. A 335 (1990) 139], the macroscopic excitation mechanism of the electric pygmy dipole resonance (PDR) is considered as owing its origin to perturbation-induced effective decomposition of a nucleus into two spherical domainsundisturbed inner region treated as a static core and dynamical layer undergoing elastic

S. I. Bastrukov; I. V. Molodtsova; D. V. Podgainy; ?. Mi?icu; H.-K. Chang

2008-01-01

400

Development of francium atomic beam for the search of the electron electric dipole moment

NASA Astrophysics Data System (ADS)

For the measurement of the electron electric dipole moment using Fr atoms, a Fr ion-atom conversion is one of the most critical process. An ion-atom converter based on the "orthotropic" type of Fr source has been developed. This converter is able to convert a few keV Fr ion beam to a thermal atomic beam using a cycle of the surface ionization and neutralization. In this article, the development of the converter is reported.

Sato, Tomoya; Ando, S.; Aoki, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Inoue, T.; Ishikawa, T.; Itoh, M.; Kato, K.; Kato, T.; Kawamura, H.; Nataraj, H. S.; Uchiyama, A.; Aoki, T.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Sakemi, Y.

2014-03-01

401

Low lying electric dipole excitations in nuclei of the rare earth region

From many experiments with low energy photon scattering on deformed rare earth nuclei we have obtained detailed information about the distribution of electric dipole strength below 4 MeV. Apart from some weaker transitions between 2 and 4 MeV we observed one, and sometimes two, very strong El-groundstate transitions around 1.5 MeV in all examined nuclei. They arise from the de-excitation

P. von Brentano; A. Zilges; R. D. Herzberg; N. V. Zamfir; U. Kneissl; R. D. Heil; H. H. Pitz; C. Wesselborg

1992-01-01

402

The Schroedinger equation with noncentral electric dipole ring-shaped potential is investigated by working in a complete square integrable basis that supports an infinite tridiagonal matrix representation of the wave operator. The three-term recursion relations for the expansion coefficients of both the angular and radial wavefunctions are presented. The discrete spectrum for the bound states is obtained by the diagonalization of the radial recursion relation. Some potential applications of this system in different fields are discussed.

Huangfu Guoqing [Department of Physics and Electronic Engineering, Weinan Teachers University, Weinan 714000 (China); Zhang Mincang [College of Physics and Information Technology, Shaanxi Normal University, Xi'an 710062 (China)

2011-04-15

403

Torque for electron spin induced by electron permanent electric dipole moment

NASA Astrophysics Data System (ADS)

The spin torque of the electron is studied in relation to the electric dipole moment (EDM) of the electron. The spin dynamics is known to be given by the spin torque and the zeta force in quantum field theory. The effect of the EDM on the torque of the spin brings a new term in the equation of motion of the spin. We study this effect for a solution of the Dirac equation with electromagnetic field.

Senami, Masato; Fukuda, Masahiro; Ogiso, Yoji; Tachibana, Akitomo

2014-10-01

404

Experimental search for the electron electric dipole moment with laser cooled francium atoms

NASA Astrophysics Data System (ADS)

A laser cooled heavy atom is one of the candidates to search for the permanent electric dipole moment (EDM) of the electron due to the enhancement mechanism and its long coherence time. The laser cooled francium (Fr) factory has been constructed to perform the electron EDM search at the Cyclotron and Radioisotope Center, Tohoku University. The present status of Fr production and the EDM measurement system is presented.

Inoue, T.; Ando, S.; Aoki, T.; Arikawa, H.; Ezure, S.; Harada, K.; Hayamizu, T.; Ishikawa, T.; Itoh, M.; Kato, K.; Kawamura, H.; Uchiyama, A.; Aoki, T.; Asahi, K.; Furukawa, T.; Hatakeyama, A.; Hatanaka, K.; Imai, K.; Murakami, T.; Nataraj, H. S.; Sato, T.; Shimizu, Y.; Wakasa, T.; Yoshida, H. P.; Yoshimi, A.; Sakemi, Y.

2014-12-01

405

Neutron electric dipole moment from supersymmetric anomalous W-boson coupling

In the supersymmetric standard model (SSM) the W boson could have a nonvanishing electric dipole moment (EDM) through a one-loop diagram mediated by the charginos and neutralinos. Then the W-boson EDM induces the EDMs of the neutron and the electron. We discuss these EDMs, taking into consideration the constraints from the neutron and electron EDMs at the one-loop level induced

Tomoko Kadoyoshi; Noriyuki Oshimo

1997-01-01

406

Electron electric-dipole-moment experiment using a cold cesium fountain

Despite its success, the Standard Model of particle physics is incomplete. One of the most sensitive tests of physics beyond the Standard Model is the search for a permanent electric-dipole-moment (EDM) of a fundamental particle such as the electron. This thesis describes a proof-of-principles electron EDM experiment using cold atoms. The experiment has a number of features that distinguish it

Jason Madjdi Amini

2006-01-01

407

MSSM predictions for the electric dipole moment of the 199Hg atom

The Minimal Supersymmetric Standard Model can possess several CP-violating phases beyond the conventional Cabibbo-Kobayashi-Maskawa phase. We calculate the contribution of these phases to T-violating nuclear forces. These forces induce a Schiff moment in the 199Hg nucleus, which is strongly limited by experiments aimed at the detection of the electric dipole moment of the mercury atom. The result for dHg is

Toby Falk; Keith A. Olive; Maxim Pospelov; Radu Roiban

1999-01-01

408

Enhancement factor for the electron electric dipole moment in francium and gold atoms

If electrons had an electric dipole moment (EDM) they would induce EDMs of\\u000aatoms. The ratio of the atomic EDM to the electron EDM for a particular atom is\\u000acalled the enhancement factor, R. We calculate the enhancement factor for the\\u000afrancium and gold atoms, with the results 910 plus\\/minus 5% for Fr and 260\\u000aplus\\/minus 15% for Au. The

T. M. R. Byrnes; V. A. Dzuba; V. V. Flambaum; D. W. Murray

1999-01-01

409

Searching for the electron electric dipole moment in an electrostatic storage ring

A non-zero permanent electric dipole moment (EDM) of an electron would violate parity and time-reversal symmetries. Non-zero EDMs are predicted in the standard model, but are unobservably small. New physics incorporating new particles and new CP-violating phases can lead, through radiative corrections, to dramatic enhancements of the electron EDM, to within a few orders of magnitude of the current experimental

David Kawall

2011-01-01

410

Search for the Permanent Electric Dipole Moment of the Electron Using Cesium

The electric dipole moment (edm) of the ground state of cesium has been measured using optical pumping and precision polarization analyzing techniques. The measured value of d_{Cs} = ( -1.8 +\\/- 6.7 +\\/- 1.8) times 10^ {-24}e cm implies that the electron edm d_{e} = ( -1.5 +\\/- 5.5 +\\/- 1.5) times 10^ {-26}e cm. This result represents more than

Sudha A. Murthy

1990-01-01

411

Search for the electric dipole moment of the electron using metastable PbO

The metastable excited state a(1)[3Sigma+] of PbO is proposed as a candidate system in which to search for an electron electric dipole moment (EDM). It is shown that the sensitivity to an electron EDM (de) could reach 10-31 e.cm-an improvement of >104 over the current limit. Observation of an electron EDM would provide definitive evidence for physics beyond the standard

D. Demille; F. Bay; S. Bickman; D. Kawall; L. Hunter; D. Krause; S. Maxwell; K. Ulmer

2001-01-01

412

Electric Dipole Moments in the MSSM at Large tan(beta)

Within the minimal supersymmetric standard model (MSSM), the large tan(beta)\\u000aregime can lead to important modifications in the pattern of CP-violating\\u000asources contributing to low energy electric dipole moments (EDMs). In\\u000aparticular, four-fermion CP-violating interactions induced by Higgs exchange\\u000ashould be accounted for alongside the constituent EDMs of quarks and electrons.\\u000aTo this end, we present a comprehensive analysis of

Durmus Demir; Oleg Lebedev; Keith A. Olive; Maxim Pospelov; Adam Ritz

2003-01-01

413

Development of Thermal Ionizer for the Search of the Electron Electric Dipole Moment

A non-zero Electric Dipole Moment (EDM) of an elementary particle means the violation of the time-reversal symmetry and the CP violation assuming the CPT invariance. The super symmetry model (SUSY) predicts the EDM large enough to be observed with the modern experimental technique. In alkali atoms, an electron EDM results in an atomic EDM enhanced by the factor Z^3alpha^2, especially

Tomohiro Hayamizu; Akihito Oikawa; Toshiya Takahashi; Hidetomo Yoshida; Masatoshi Itoh; Yasuhiro Sakemi

2009-01-01

414

The current distribution and input impedance of an electric dipole antenna operating in a cold magnetoplasma at very low frequency (VLF) is determined through numerical simulation. A full wave solution of Maxwell's equations using a finite-difference frequency-domain (FDFD) method is implemented to simulate electromagnetic wave propagation in this highly anisotropic medium. The classical perfectly matched-layer (PML) boundary condition is found

Timothy W. Chevalier; Umran S. Inan; Timothy F. Bell

2008-01-01

415

Electric Transition Dipole Moment in pre-Born-Oppenheimer Molecular Structure Theory

This paper presents the calculation of the electric transition dipole moment in a pre-Born-Oppenheimer framework. Electrons and nuclei are treated equally in terms of the parametrization of the non-relativistic total wave function, which is written as a linear combination of basis functions constructed with explicitly correlated Gaussian functions and the global vector representation. The integrals of the electric transition dipole moment are derived corresponding to these basis functions in both the length and the velocity representation. The complete derivation and the calculations are performed in laboratory-fixed Cartesian coordinates without relying on coordinates which separate the center of mass from the translationally invariant degrees of freedom. The effect of the overall motion is eliminated via translationally invariant integral expressions. As a numerical example the electric transition dipole moment is calculated between two rovibronic levels of the H2 molecule assignable to the lowest rovibrational states of the X ^1Sigma^+_g and B ^1Sigma^+_u electronic states in the clamped-nuclei framework. This is the first evaluation of this quantity in a full quantum mechanical treatment without relying on the Born-Oppenheimer approximation.

Benjamin Simmen; Edit Matyus; Markus Reiher

2014-06-14

416

Electric transition dipole moment in pre-Born-Oppenheimer molecular structure theory.

This paper presents the calculation of the electric transition dipole moment in a pre-Born-Oppenheimer framework. Electrons and nuclei are treated equally in terms of the parametrization of the non-relativistic total wave function, which is written as a linear combination of basis functions constructed from explicitly correlated Gaussian functions and the global vector representation. The integrals of the electric transition dipole moment are derived corresponding to these basis functions in both the length and the velocity representation. The calculations are performed in laboratory-fixed Cartesian coordinates without relying on coordinates which separate the center of mass from the translationally invariant degrees of freedom. The effect of the overall motion is eliminated through translationally invariant integral expressions. The electric transition dipole moment is calculated between two rovibronic levels of the H2 molecule assignable to the lowest rovibrational states of the X (1)?(g)(+) and B (1)?(u)(+) electronic states in the clamped-nuclei framework. This is the first evaluation of this quantity in a full quantum mechanical treatment without relying on the Born-Oppenheimer approximation. PMID:25338879

Simmen, Benjamin; Mátyus, Edit; Reiher, Markus

2014-10-21

417

Twin rotating coils for cold magnetic measurements of 15 m long LHC dipoles

We describe here a new harmonic coil system for the field measurement of the superconducting, twin aperture LHC dipoles and the associated corrector magnets. Besides field measurements the system can be used as an antenna to localize the quench origin. The main component is a 16 m long rotating shaft, made up of 13 ceramic segments, each carrying two tangential

J. Billan; L. Bottura; M. Buzio; G. D'Angelo; G. Deferne; O. Dunkel; P. Legrand; A. Rijllart; A. Siemko; P. Sievers; S. Schloss; L. Walckiers

2000-01-01

418

Development of cos-theta Nb{sub 3}Sn dipole magnets for VLHC

This paper describes the double aperture dipole magnets developed for a VLHC based on Nb{sub 3}Sn superconductor, a cos-theta coil, cold and warm iron yokes, and the wind-and-react fabrication technique. Status of the model R and D program, strand and cable and other major component development are also discussed.

Alexander Zlobin et al.

2001-07-20

419

Reviews of Geophysics Vol. 3, No. 2 May 1965 Trapped Orbits in a Magnetic Dipole Field

of a charged particle in a dipole magnetic field. It provides an extensive discussion of the equations integration. 1. INTRODUCTION The problem of determining the motion of a charged particle in the earth] and was subsequently studied by him and several others in connection, with auroral phenomena and cosmic rays. Because

Knill, Oliver

420

ERIC Educational Resources Information Center

In this paper we consider the relativistic polarization of a moving magnetic dipole and show that this effect can be understood via the relativistic generalization of Kirchhoff's first law to a moving closed circuit with a steady current. This approach allows us to better understand the law of relativistic transformation of four-current density

Kholmetskii, Alexander L.; Yarman, T.

2010-01-01

421

Disk Formation by Asymptotic Giant Branch Winds in Dipole Magnetic Fields

NASA Astrophysics Data System (ADS)

We present a simple, robust mechanism by which an isolated star can produce an equatorial disk. The mechanism requires that the star have a simple dipole magnetic field on the surface and an isotropic wind acceleration mechanism. The wind couples to the field, stretching it until the field lines become mostly radial and oppositely directed above and below the magnetic equator, as occurs in the solar wind. The interaction between the wind plasma and magnetic field near the star produces a steady outflow in which magnetic forces direct plasma toward the equator, constructing a disk. In the context of a slow (10 km s-1) outflow (10-5 Msolar yr-1) from an asymptotic giant branch star, MHD simulations demonstrate that a dense equatorial disk will be produced for dipole field strengths of only a few Gauss on the surface of the star. A disk formed by this model can be dynamically important for the shaping of planetary nebulae.

Matt, Sean; Balick, Bruce; Winglee, Robert; Goodson, Anthony

2000-12-01

422

The yoke in SSC dipole magnets provides mechanical support to the collared coil as well as serving as a magnetic element. The yoke and skin are used to increase the coil prestress and reduce collar deflections under excitation. Yokes split on the vertical or horizontal mid-plane offer different advantages in meeting these objectives. To evaluate the relative merits of the two configuration a 1.8 m model dipole was assembled and tested first with horizontally split and then with vertically split yoke laminations. The magnet was extensively instrumented to measure azimuthal and axial stresses in the coil and the cold mass skin resulting from cooldown and excitation. Mechanical behavior of this magnet with each configuration is compared with that of other long and short models and with calculations. 13 refs., 5 figs.

Strait, J.; Coulter, K.; Jaffery, T.; Kerby, J.; Koska, W.; Lamm, M.J.

1990-05-03

423

Magnetic dipole moment estimates for an ancient lunar dynamo

NASA Technical Reports Server (NTRS)

The four measured planetary magnetic moments combined with a recent theoretical prediction for dynamo magnetic fields suggests that no dynamo exists in the moon's interior today. For the moon to have had a magnetic moment in the past of sufficient strength to account for at least some of the lunar rock magnetism, the rotation would have been about twenty times faster than it is today and the radius of the fluid, conducting core must have been about 750 km. The argument depends on the validity of the Busse solution to the validity of the MHD problem of planetary dynamos.

Anderson, K. A.

1983-01-01

424

Vanishing of dipole matrix elements at level crossings.

NASA Technical Reports Server (NTRS)

Demonstration that the vanishing of certain coupling matrix elements at level crossings follow from angular momentum commutation relations. A magnetic dipole transition having delta M = plus or minus 1, induced near a crossing of the levels in a nonzero magnetic field, is found to have a dipole matrix element comparable to or smaller than the quotient of the level separation and the field. This result also applies in the analogous electric field electric dipole case.

Kocher, C. A.

1972-01-01

425

Test results of RD3c, a Nb3Sn common-coil racetrack dipole magnet

The superconducting magnet group at Lawrence Berkeley National Laboratory has been developing racetrack coil technology for economical, high-field accelerator magnets from brittle superconductor. Recent tests have demonstrated 1) robust, reusable, double-layer, flat racetrack, wind and react Nb3Sn coils, 2) a reusable, easily assembled coil-support structure that can minimize conductor movement and 3) nearly 15 T dipole fields, without conductor degradation.

A. F. Lietzke; S. Caspi; L. Chiesa; M. Coccoli; D. R. Dietderich; P. Ferracin; S. A. Gourlay; R. R. Hafalia; A. D. McInturff; G. Sabbi; R. M. Scanlan

2003-01-01

426

The 50mm aperture prototype collider ordered wound dipole connector magnets have been modeled with finite element techniques considering the individual and combined load cases of the preloading from keys, cooldown to 4 K and the effect of magnetic forces during energizing. Results of the analysis are presented as longitudinal, transverse and shear stresses for the ordered wound coils and as maximum von Mises stress for the carbon steel outer laminations, the stainless steel inner lamination, and the carbon steel keys.

Tran, Vu H.

1993-04-01

427

Structural performance of the first SSC (Superconducting Super Collider) Design B dipole magnet

The first Design B Superconducting Super Collider (SSC) dipole magnet has been successfully tested. This magnet was heavily instrumented with temperature and strain gage sensors in order to evaluate its adherence to design constraints and design calculations. The instrumentation and associated data acquisition system allowed monitoring of the magnet during cooldown, warmup, and quench testing. This paper will focus on the results obtained from structural measurements on the suspension system during normal and rapid cooldowns and during quench studies at full magnet current. 4 refs., 9 figs.

Nicol, T.H.

1989-09-01

428

Prospects for the measurement of the electron electric dipole moment using YbF

We discuss an experiment underway at Imperial College London to measure the permanent electric dipole moment (EDM) of the electron using a molecular beam of YbF. We describe the measurement method, which uses a combination of laser and radiofrequency resonance techniques to detect the spin precession of the YbF molecule in a strong electric field. We pay particular attention to the analysis scheme and explore some of the possible systematic effects which might mimic the EDM signal. Finally, we describe technical improvements which should increase the sensitivity by more than an order of magnitude over the current experimental limit.

Sauer, B E; Kara, D M; Smallman, I J; Tarbutt, M R; Hinds, E A

2011-01-01

429

Modeling the magnetic field of Mercury using the Time Dependent Equivalent Source Dipole method

NASA Astrophysics Data System (ADS)

We introduce the Time Dependent Equivalent Source Dipole (TD-ESD) method developed with the purpose of modeling the Hermean magnetic field. It takes into account the partial orbital coverage provided by MErcury Surface, Space ENvironment, Geochemistry, and Ranging (MESSENGER) mission. The TD-ESD method is based on the Equivalent Source Dipole approach, which has been largely used to downward or upward continue to constant altitude measurements of magnetic fields of crustal origin, on local or global scale. In this present application to Mercury, for which an internal core field is expected, the dipoles are uniformly distributed at a spherical surface placed deep into the planet's interior. Both their magnitude and directions are not a priori imposed and are free to evolve with time. Using synthetic data generated at MESSENGER orbit positions we successfully recover the three components of the magnetic field. We also recover the temporal variation that we a priori imposed. We find that downward and upward continuation is possible over a certain limited region. The resulting field is within 6% of the initial field for altitudes ranging between -100km and 1500km. Here we present the first constant altitude magnetic field maps derived from MESSENGER measurements acquired during the first mercury's solar day. We identify a strong time dependent signature of the external magnetic field, even when only measurements over the northern hemisphere below ~1000 km altitude are used. A future improvement of the method will consist in the simultaneous analysis of the external and internal magnetic fields.

Oliveira, Joana; Langlais, Benoit; Amit, Hagay; Pais, Maria Alexandra

2014-05-01

430

Near-field characteristics of electric dipole antennas in the inner magnetosphere

NASA Astrophysics Data System (ADS)

Electric dipole antennas are commonly used in space plasmas with applications that range from radio frequency probing of the magnetosphere to plasma diagnostics. With the recent interest in the in-situ injection of ELF/VLF waves for the study of magnetospheric wave-particle interactions, the characterization of the antenna-plasma coupling behavior in this regime is of primary importance. The coupling considered in this dissertation occurs in an operating environment that corresponds to magnetospheric conditions found between L=2 and L=3 in the geomagnetic equatorial plane. The near field of the antenna consists of a plasma sheath which directly affects the terminal impedance properties. Inside the sheath region, the plasma dynamics are highly nonlinear and must be solved numerically. In order to optimally inject VLF waves and thereby maximize the antenna-plasma coupling response, it is necessary to determine the characteristics of electric dipole antennas operating within this region of space. This dissertation addresses the efficacy of using electric dipole antennas as in-situ wave injection instruments and focuses on the near-field coupling of these antennas to the environment in which they are immersed. A two-tiered hydrodynamic approach has been developed to solve for the plasma dynamics in the region surrounding the antenna. First, a three-dimensional full wave solution of Maxwell's equations is implemented to simulate the current distribution and input impedance of an electric dipole antenna operating in a cold magnetoplasma at VLF. It is shown that the current distribution for antennas with length <100 m is approximately triangular for magnetospheric conditions considered herein. Calculated variations of input impedance as a function of drive frequency are presented for two case studies and compared with predictions of existing analytical work. This model is then extended to include finite temperature effects allowing for the determination of the sheath characteristics as a function of drive frequency and voltage. The primary assumptions underlying the closure mechanisms for the infinite set of fluid moments are examined through theoretical observations and simulated comparisons of the various truncation schemes. Results from these two models allow for the complete characterization of the near-field properties of electric dipole antennas operating in this highly anisotropic environment.

Chevalier, Timothy W.

431

The electric and magnetic form factors of the proton

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.

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. irca; M. Weinriefer

2014-07-29

432

Design of Racetrack Coils for High Field Dipole Magnets

The magnet group at LBNL is currently in the process of developing high-field accelerator magnets for use in future colliders. One of the primary challenges is to provide a design which is cost-effective and simple to manufacture, at the same time resulting in good training performance and field quality adequate for accelerator operation. Recent studies have focused on a racetrack geometry that has the virtues of simplicity and conductor compatibility. The results have been applied to the design of a series of prototype high-field magnets based on Nb{sub 3}Sn conductor.

Sabbi, G.; Caspi, S.; Gourlay, S.A.; Hafalia, R.; Jackson, A.; Lietzke, A.; McInturff, A.D.; Scanlan, R.M.

2000-09-08

433

A comprehensive description of the muon storage ring and its operation is given, and the final results of the experiment are presented and discussed. The anomalous magnetic moments of positive and negative muons are found to be amu+ = 1165911(11) × 10-9 and amu- = 1165937(12) × 10-9 giving an average value for muons of amu = 1165924(8.5) × 10-9.

J. Bailey; K. Borer; F. Combley; H. Drumm; C. Eck; F. J. M. Farley; J. H. Field; W. Flegel; P. M. Hattersley; F. Krienen; F. Lange; G. Lebée; E. McMillan; G. Petrucci; E. Picasso; O. Rúnolfsson; W. von Rüden; R. W. Williams; S. Wojcicki

1979-01-01

434

Pendlebury $\\textit{et al.}$ [Phys. Rev. A $\\textbf{70}$, 032102 (2004)] were the first to investigate the role of geometric phases in searches for an electric dipole moment (EDM) of elementary particles based on Ramsey-separated oscillatory field magnetic resonance with trapped ultracold neutrons and comagnetometer atoms. Their work was based on the Bloch equation and later work using the density matrix corroborated the results and extended the scope to describe the dynamics of spins in general fields and in bounded geometries. We solve the Schr\\"odinger equation directly for cylindrical trap geometry and obtain a full description of EDM-relevant spin behavior in general fields, including the short-time transients and vertical spin oscillation in the entire range of particle velocities. We apply this method to general macroscopic fields and to the field of a microscopic magnetic dipole.

A. Steyerl; C. Kaufman; G. Müller; S. S. Malik; A. M. Desai; R. Golub

2014-05-23

435

Progress toward a measurement of the electron's electric dipole moment using PbO

NASA Astrophysics Data System (ADS)

Searches for permanent electric dipole moments (EDMs) of fundamental particles provide a way to detect new sources of time-reversal symmetry violation. We present recent results on an experiment to search for the electron's EDM, using the polar molecule PbO. PbO offers several advantages compared to atoms, including a much larger effective internal electric field (>10 GV/cm) and parity doubling, which can be used to reverse the effective internal electric field without reversing the laboratory electric field. This technique allows for significant rejection of systematic errors. Recent improvements to the experiment have resulted in statistical sensitivities of approximately 1 x10-27 ecm/?day, which could allow for an improvement over the current experimental limit on the electron EDM in only a few days of integration time. Details of the approach and studies of possible systematic errors will be described.

Eckel, Stephen; Hamilton, Paul; Kirilov, Emil; Smith, Hunter; Demille, David

2012-06-01

436

Dipole-approximation magnetic fields in strong laser beams

Many investigators have been exploring the intensity domain where, in laser interactions with atoms, the v\\/c effects of magnetic fields are important, but it is not necessary to treat the (v\\/c)2 effects of a full-fledged relativistic treatment. We delineate the intensity regimes as a function of frequency where one must consider magnetic fields, but not relativistic effects per se. Since

H. R. Reiss

2001-01-01

437

Control of magnetism by electric fields

NASA Astrophysics Data System (ADS)

The electrical manipulation of magnetism and magnetic properties has been achieved across a number of different material systems. For example, applying an electric field to a ferromagnetic material through an insulator alters its charge-carrier population. In the case of thin films of ferromagnetic semiconductors, this change in carrier density in turn affects the magnetic exchange interaction and magnetic anisotropy; in ferromagnetic metals, it instead changes the Fermi level position at the interface that governs the magnetic anisotropy of the metal. In multiferroics, an applied electric field couples with the magnetization through electrical polarization. This Review summarizes the experimental progress made in the electrical manipulation of magnetization in such materials, discusses our current understanding of the mechanisms, and finally presents the future prospects of the field.

Matsukura, Fumihiro; Tokura, Yoshinori; Ohno, Hideo

2015-03-01

438

Control of magnetism by electric fields.

The electrical manipulation of magnetism and magnetic properties has been achieved across a number of different material systems. For example, applying an electric field to a ferromagnetic material through an insulator alters its charge-carrier population. In the case of thin films of ferromagnetic semiconductors, this change in carrier density in turn affects the magnetic exchange interaction and magnetic anisotropy; in ferromagnetic metals, it instead changes the Fermi level position at the interface that governs the magnetic anisotropy of the metal. In multiferroics, an applied electric field couples with the magnetization through electrical polarization. This Review summarizes the experimental progress made in the electrical manipulation of magnetization in such materials, discusses our current understanding of the mechanisms, and finally presents the future prospects of the field. PMID:25740132

Matsukura, Fumihiro; Tokura, Yoshinori; Ohno, Hideo

2015-03-01

439

Electric dipole moment of neutron in the Kobayashi-Maskawa model with four generations of quarks

We show that the existence of a possible fourth heavy generation of quarks gives rise to a significant enhancement to the neutron electric dipole moment in comparison with the Standard Model prediction. The smaller degree of suppression in this case is linked to the presence of the operators of dimension $\\leq$ 6 which enter into the effective Lagrangian with coefficients proportional to the square of the top quark mass. Numerically, the enhancement is mainly associated with chromoelectric dipole moment of the s quark which appears at three loop level, of the order $\\al_s\\al_w^2m_sm_t^2/m^4_w$ from the CP-odd combination of mixing angles between second, third and fourth generations. Its value is calculated explicitly in the limit of large masses of the fourth generation of quarks. The corresponding contribution to the electric dipole moment of the neutron is $5\\cdot10^{-30} e\\cdot cm$ in the most optimistic scenarios about the values of the Kobayashi-Maskawa matrix elements. The additive renormalization of $\\theta$-term in this model is estimated as $10^{-13}$.

C. Hamzaoui; M. E. Pospelov

1995-03-30

440

Observation of coupled magnetic and electric domains

Ferroelectromagnets are an interesting group of compounds that complement purely (anti-)ferroelectric or (anti-)ferromagnetic materials-they display simultaneous electric and magnetic order. With this coexistence they supplement materials in which magnetization can be induced by an electric field and electrical polarization by a magnetic field, a property which is termed the magnetoelectric effect. Aside from its fundamental importance, the mutual control of

M. Fiebig; Th. Lottermoser; D. Fröhlich; A. V. Goltsev; R. V. Pisarev

2002-01-01

441

Neglecting the curvature terms, the magnetic field and the vector potential which generate the multipole longitudinal periodic structure in a superconducting dipole magnet are found. Using this field and the standard Hamiltonian perturbation theory, the tune shifts due to this periodic pattern in the superconducting dipole magnets are estimated for the Superconducting Super Collider (SSC) machine. The results suggest that this tune shift is very small for most of the multipoles and could be ignored for the SSC. However, for the quadrupole longitudinal oscillation pattern, the tune shift relative to the amplitude of this oscillation could be of the order of 10{sup {minus}5} and may not be ignored. 12 refs., 4 figs., 3 tabs.

Lopez, G.; Chen, S.

1991-10-01

442

Studies of time dependence of fields in TEVATRON superconducting dipole magnets

The time variation in the magnetic field of a model Tevatron dipole magnet at constant excitation current has been studied. Variations in symmetry allowed harmonic components over long time ranges show a log t behavior indicative of ''flux creep.'' Both short time range and long time range behavior depend in a detailed way on the excitation history. Similar effects are seen in the remnant fields present in full-scale Tevatron dipoles following current ramping. Both magnitudes and time dependences are observed to depend on details for the ramps, such as ramp rate, flattop duration, and number of ramps. In a few magnets, variations are also seen in symmetry unallowed harmonics. 9 refs., 10 figs.

Hanft, R.W.; Brown, B.C.; Herrup, D.A.; Lamm, M.J.; McInturff, A.D.; Syphers, M.J.

1988-08-22

443

Magnetic measurements on the ring dipoles and quadrupoles for the Los Alamos proton storage ring

This paper discusses magnetic measurements and shimming performed on the ring dipoles and quadrupoles for the Los Alamos Proton Storage Ring (PSR). For the dipoles, point-by-point field maps were obtained using a search coil that could be scanned over a three-dimensional grid. By appropriate machining of removable end blocks, all magnet lengths were adjusted to within 0.01% of a nominal value and all integrated multipoles were set within tolerance. Integrated fields of 20 PSR quadrupoles were measured using a rotating ''Morgan Coil'' and a digital spectrum analyzer. The magnets were shimmed to specifications by adjusting steel bolts threaded through the field clamps. 3 refs., 5 figs., 4 tabs.

Schermer, R.I.; Blind, B.; Jason, A.J.; Sawyer, G.A.

1985-01-01

444

3D Design, Contruction, and Field Analysis of CIS Main Dipole Magnets

NASA Astrophysics Data System (ADS)

The lattice for CIS ( Cooler Injection Synchroton ) requires four laminated 90^circ main dipole magnets with bending radius ? = 1.273 m, EFL = 2 m, and an edge angle of 12^circ. Optimum Cooler injection and injection in the planned 15 GeV LISS ring requires operation up to about 1.75 T. Initial operation of 1 Hz, with later upgrade to 5 Hz is planned. We will present 2D and 3D field calculations used to optimize the shape of laminations and endpacks of the magnet. Endpacks are designed to determine edge angle and to compensate hexapole components, in particular above 1.4 T where saturation becomes significant. The large dipole curvature required a new type of dipole construction. Each magnet consists of wedge shaped blocks fabricated from stamped lamination of cold rolled low carbon iron. B-stage (dry) epopy was used for bonding and insulation. The end blocks are machined to include the calculated 3D shape of the endpacks. All four magnets were mapped in the field range from 0.3 T - 1.8 T. Comparison of calculations and data in terms of B(I) curves, EFL, edge angle, and hexapole component as function of field excitation will be presented. The constructed magnets are well within expected specifications.

Berg, G. P. A.; Fox, W.; Friesel, D. L.; Rinckel, T.

1997-05-01

445

Interferometric methods for mapping static electric and magnetic fields

NASA Astrophysics Data System (ADS)

The mapping of static electric and magnetic fields using electron probes with a resolution and sensitivity that are sufficient to reveal nanoscale features in materials requires the use of phase-sensitive methods such as the shadow technique, coherent Foucault imaging and the Transport of Intensity Equation. Among these approaches, image-plane off-axis electron holography in the transmission electron microscope has acquired a prominent role thanks to its quantitative capabilities and broad range of applicability. After a brief overview of the main ideas and methods behind field mapping, we focus on theoretical models that form the basis of the quantitative interpretation of electron holographic data. We review the application of electron holography to a variety of samples (including electric fields associated with p-n junctions in semiconductors, quantized magnetic flux in superconductors and magnetization topographies in nanoparticles and other magnetic materials) and electron-optical geometries (including multiple biprism, amplitude and mixed-type set-ups). We conclude by highlighting the emerging perspectives of (i) three-dimensional field mapping using electron holographic tomography and (ii) the model-independent determination of the locations and magnitudes of field sources (electric charges and magnetic dipoles) directly from electron holographic data.

Pozzi, Giulio; Beleggia, Marco; Kasama, Takeshi; Dunin-Borkowski, Rafal E.

2014-02-01

446

In order to survive, animals must quickly and accurately locate prey, predators, and conspecifics using the signals they generate. The signal source location can be estimated using multiple detectors and the inverse relationship between the received signal intensity (RSI) and the distance, but difficulty of the source localization increases if there is an additional dependence on the orientation of a signal source. In such cases, the signal source could be approximated as an ideal dipole for simplification. Based on a theoretical model, the RSI can be directly predicted from a known dipole location; but estimating a dipole location from RSIs has no direct analytical solution. Here, we propose an efficient solution to the dipole localization problem by using a lookup table (LUT) to store RSIs predicted by our theoretically derived dipole model at many possible dipole positions and orientations. For a given set of RSIs measured at multiple detectors, our algorithm found a dipole location having the closest matching normalized RSIs from the LUT, and further refined the location at higher resolution. Studying the natural behavior of weakly electric fish (WEF) requires efficiently computing their location and the temporal pattern of their electric signals over extended periods. Our dipole localization method was successfully applied to track single or multiple freely swimming WEF in shallow water in real-time, as each fish could be closely approximated by an ideal current dipole in two dimensions. Our optimized search algorithm found the animals positions, orientations, and tail-bending angles quickly and accurately under various conditions, without the need for calibrating individual-specific parameters. Our dipole localization method is directly applicable to studying the role of active sensing during spatial navigation, or social interactions between multiple WEF. Furthermore, our method could be extended to other application areas involving dipole source localization. PMID:23805244

Jun, James Jaeyoon; Longtin, André; Maler, Leonard

2013-01-01

447

Fabrication and component testing results for a Nb{sub 3}Sn dipole magnet

At present, the maximum field achieved in accelerator R&D dipoles is slightly over 10T, with NbTi conductor at 1.8 K. Although Nb{sub 3}Sn has the potential to achieve much higher fields, none of the previous dipoles constructed from Nb{sub 3}Sn have broken the 10T barrier. We report here on the construction of a dipole with high current density Nb{sub 3}Sn with a predicted short sample limit of 13T. A wind and react technique, followed by epoxy impregnation of the fiberglass insulated coils, was used. The problems identified with the use of Nb{sub 3}SD in earlier dipole magnets were investigated in a series of supplemental tests. This includes measurement of the degradation of J{sub c} with transverse strain, cabling degradation, joint resistance measurements, and epoxy strength tests. In addition, coff assembly techniques were developed to ensure that adequate prestress could be applied without damaging the reacted Nb{sub 3}Sn cable. We report here the results of these tests and the construction status of this 50 mm bore dipole.

Dell`Orco, D.; Scanlan, R.M.; Taylor, C.E.; Lietzke, A.; Caspi, S.; van Oort, J.M.; McInturff, A.D.

1994-10-01

448

Patterned time-orbiting potentials for the confinement and assembly of magnetic dipoles

We present an all-magnetic scheme for the assembly and study of magnetic dipoles within designed confinement profiles that are activated on micro-patterned permalloy films through a precessing magnetic field. Independent control over the confinement and dipolar interactions is achieved by tuning the strength and orientation of the revolving field. The technique is demonstrated with superparamagnetic microspheres field-driven to assemble into closely packed lattice sheets, quasi-1D and other planar structures expandable into dipolar arrays that mirror the patterned surface motifs. PMID:24185093

Chen, A.; Sooryakumar, R.

2013-01-01

449

An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a technique for characterizing the nonlinear fields of the beam transport system. Two air-core dipole magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the electron beam. Fourier decomposition of beam position monitor data was then used to measure the amplitude of these frequencies at different positions along the beamline. For a purely linear transport system one expects to find solely the frequencies that were applied to the dipoles with amplitudes that depend on the phase advance of the lattice. In the presence of nonlinear fields one expects to also find harmonics of the driving frequencies that depend on the order of the nonlinearity. The technique was calibrated using one of the sextupole magnets in a CEBAF beamline and then applied to a dipole to measure the sextupole and octupole strength of the magnet. A comparison is made between the beam-based measurements, results from TOSCA and data from our Magnet Measurement Facility.

M. Spata, G.A. Krafft

2011-09-01

450

Prospects for Searching Axion-like Particle Dark Matter with Dipole, Toroidal and Wiggler Magnets

In this work we consider searches for dark matter made of axions or axion-like particles (ALPs) using resonant radio frequency cavities inserted into dipole magnets from particle accelerators, wiggler magnets developed for accelerator based advanced light sources, and toroidal magnets similar to those used in particle physics detectors. We investigate the expected sensitivity of such ALP dark matter detectors and discuss the engineering aspects of building and tuning them. Brief mention is also made of even stronger field magnets that are becoming available due to improvements in magnetic technology. It is concluded that new experiments utilizing already existing magnets could greatly enlarge the mass region in searches for axion-like dark matter particles.

Oliver K. Baker; Michael Betz; Fritz Caspers; Joerg Jaeckel; Axel Lindner; Andreas Ringwald; Yannis Semertzidis; Pierre Sikivie; Konstantin Zioutas

2011-10-10

451

Production and study of high-beta plasma confined by a superconducting dipole magnet

The Levitated Dipole Experiment (LDX) [J. Kesner et al., in Fusion Energy 1998, 1165 (1999)] is a new research facility that is exploring the confinement and stability of plasma created within the dipole field produced by a strong superconducting magnet. Unlike other configurations in which stability depends on curvature and magnetic shear, magnetohydrodynamic stability of a dipole derives from plasma compressibility. Theoretically, the dipole magnetic geometry can stabilize a centrally peaked plasma pressure that exceeds the local magnetic pressure ({beta}>1), and the absence of magnetic shear allows particle and energy confinement to decouple. In initial experiments, long-pulse, quasi-steady-state microwave discharges lasting more than 10 s have been produced that are consistent with equilibria having peak beta values of 20%. Detailed measurements have been made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. In these initial experiments, the high-field superconducting floating coil was supported by three thin supports. The plasma is created by multifrequency electron cyclotron resonance heating at 2.45 and 6.4 GHz, and a population of energetic electrons, with mean energies above 50 keV, dominates the plasma pressure. Creation of high-pressure, high-beta plasma is possible only when intense hot electron interchange instabilities are stabilized by sufficiently high background plasma density. A dramatic transition from a low-density, low-beta regime to a more quiescent, high-beta regime is observed when the plasma fueling rate and confinement time become sufficiently large.

Garnier, D.T.; Hansen, A.; Mauel, M.E.; Ortiz, E.; Boxer, A.C.; Ellsworth, J.; Karim, I.; Kesner, J.; Mahar, S.; Roach, A. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States); Plasma Science and Fusion Center, MIT, Cambridge, Massachusetts 02139 (United States)

2006-05-15

452

The permanent electric dipole moment of thorium sulfide, ThS

Numerous rotational lines of the (18.26)1-X{sup 1}?{sup +} band system of thorium sulfide, ThS, were recorded near 547.6 nm at a resolution of approximately 30 MHz. Measurements were made under field-free conditions, and in the presence of a static electric field. The field-free spectrum was analyzed to produce rotational and ?-doubling parameters. The Stark shifts induced by the electric field were analyzed to determine permanent electric dipole moments, ?{sup -vector}{sub el}, of 4.58(10) D and 6.72(5) D for the X{sup 1}?{sup +} (v = 0) and (18.26)1 states, respectively. The results are compared with the predictions of previous and new electronic structure calculations for ThS, and the properties of isovalent ThO.

Le, Anh; Steimle, Timothy C., E-mail: Tsteimle@ASU.edu [Department of Chemistry and Biochemistry, Arizona State University, Tempe, Arizona 85287-1604 (United States); Heaven, Michael C. [Department of Chemistry, Emory University, Atlanta, Georgia 30322 (United States)] [Department of Chemistry, Emory University, Atlanta, Georgia 30322 (United States)

2014-01-14

453

The permanent electric dipole moment of thorium sulfide, ThS.

Numerous rotational lines of the {18.26}1-X(1)?(+) band system of thorium sulfide, ThS, were recorded near 547.6 nm at a resolution of approximately 30 MHz. Measurements were made under field-free conditions, and in the presence of a static electric field. The field-free spectrum was analyzed to produce rotational and ?-doubling parameters. The Stark shifts induced by the electric field were analyzed to determine permanent electric dipole moments, ??el, of 4.58(10) D and 6.72(5) D for the X(1)?(+) (v = 0) and {18.26}1 states, respectively. The results are compared with the predictions of previous and new electronic structure calculations for ThS, and the properties of isovalent ThO. PMID:24437877

Le, Anh; Heaven, Michael C; Steimle, Timothy C

2014-01-14

454

Enhancement of the electron electric dipole moment in Eu{sup 2+}

Recently, the ferroelectric Eu{sub 0.5}Ba{sub 0.5}TiO{sub 3} was suggested for experimental searches of the electron electric dipole moment. To analyze results of the experiment and interpret them in terms of fundamental constants, the effective electric field E{sub eff} acting on unpaired electrons of the europium cation should be calculated. In the present paper we consider Eu{sup 2+} cation in the uniform external electric field E{sub ext} as the first step and important starting point toward the calculation of E{sub eff} in the real solid. We have performed high-level electronic structure correlation calculations using the coupled clusters theory compared to other approaches. The calculated value of the field enhancement coefficient is K=E{sub eff}/E{sub ext}=-4.6.

Skripnikov, L.V.; Titov, A.V.; Petrov, A. N.; Mosyagin, N. S. [Petersburg Nuclear Physics Institute, Gatchina, Leningrad District 188300 (Russian Federation); Sushkov, O. P. [School of Physics, University of New South Wales, Sydney 2052 (Australia)

2011-08-15

455

Ground state magnetic dipole moment of 35K

The ground state magnetic moment of 35K has been measured using the technique of nuclear magnetic resonance on beta-emitting nuclei. The short-lived 35K nuclei were produced following the reaction of a 36Ar primary beam of energy 150 MeV/nucleon incident on a Be target. The spin polarization of the 35K nuclei produced at 2 degrees relative to the normal primary beam axis was confirmed. Together with the mirror nucleus 35S, the measurement represents the heaviest T = 3/2 mirror pair for which the spin expectation value has been obtained. A linear behavior of gp vs. gn has been demonstrated for the T = 3/2 known mirror moments and the slope and intercept are consistent with the previous analysis of T = 1/2 mirror pairs.

T. J. Mertzimekis; P. F. Mantica; A. D. Davies; S. N. Liddick; B. E. Tomlin

2006-02-02

456

NASA Astrophysics Data System (ADS)

The characteristic of electric dipole at high-k/SiO2 interface is quantitatively analyzed. The dipoles of HfO2/SiO2 and HfGdOx/SiO2 systems are experimentally estimated to be about -0.38 and -1.03 V, respectively. The dipole formation is explained by the dielectric contact induced gap states (DCIGS). The charge neutrality level (CNL) of the DCIGS is for the first time utilized to study the dipole moment. The charge transfer due to different CNLs of high-k and SiO2 is considered to be the dominant origin of dipole formation. The prediction by this model is in good agreement with the experimental data.

Wang, Xiaolei; Han, Kai; Wang, Wenwu; Ma, Xueli; Xiang, Jinjuan; Chen, Dapeng; Zhang, Jing

2011-10-01

457

Search for a permanent electric dipole moment on {sup 199}Hg as a test of T-violation

The existence of an electric dipole moment (edm) on a non-degenerate quantum system would be evidence of both parity (P) and time-reversal (T) symmetry violation. The search for an edm is motivated by the long-standing observation of CP violation in the kaon system. The signature of an edm in our experiment is a measured relative shift in the precession frequency between two cells containing optically pumped {sup 199}Hg vapor in a common external magnetic field when an oppositely directed electric field is applied. After a total averaging time of t {approx} 10{sup 6} s our experiment has produced a statistical uncertainty of 3 x 10{sup -9} Hz, corresponding to an edm of 3 x 10{sup -28} e-cm (with la 10 kV/cm applied electric field) and consistent with the shot noise limit. This corresponds to the smallest energy shift ever seen in any experiment. However, possible systematic effects may limit our sensitivity. The measurement of a non-zero edm would be direct evidence of T violation, while a result consistent with zero sets limits on possible sources of T violation giving rise to an edm. Since {sup 199}Hg has a {sup 1}S{sub 0} electronic configuration it is primarily sensitive to electron-nucleon and hadronic T-violating effects. Results from our current experiment will be discussed along with plans for the future.

Klipstein, W.M.; Jacobs, J.P.; Lamoreaux, S.K. [and others

1993-05-01

458

Zeeman interaction in ThO H3?1 for the electron electric-dipole-moment search

NASA Astrophysics Data System (ADS)

The current limit on the electron's electric dipole moment, |de|<8.7×10-29 ecm (90% confidence), was set using the molecule thorium monoxide (ThO) in the J =1 rotational level of its H3?1 electronic state [J. Baron et al., Science 343, 269 (2014), 10.1126/science.1248213]. This state in ThO is very robust against systematic errors related to magnetic fields or geometric phases, due in part to its ?-doublet structure. These systematics can be further suppressed by operating the experiment under conditions where the g-factor difference between the ? doublets is minimized. We consider the g factors of the ThO H3?1 state both experimentally and theoretically, including dependence on ? doublets, the rotational level, and the external electric field. The calculated and measured values are in good agreement. We find that the g-factor difference between ? doublets is smaller in J =2 than in J =1 and reaches zero at an experimentally accessible electric field. This means that the H ,J=2 state should be even more robust against a number of systematic errors compared to H ,J=1.

Petrov, A. N.; Skripnikov, L. V.; Titov, A. V.; Hutzler, N. R.; Hess, P. W.; O'Leary, B. R.; Spaun, B.; DeMille, D.; Gabrielse, G.; Doyle, J. M.

2014-06-01

459

Electron electric dipole moment as a sensitive probe of PeV scale physics

NASA Astrophysics Data System (ADS)

We give a quantitative analysis of the electric dipole moments as a probe of high scale physics. We focus on the electric dipole moment of the electron since the limit on it is the most stringent. Further, theoretical computations of it are free of QCD uncertainties. The analysis presented here first explores the probe of high scales via electron electric dipole moment (EDM) within minimal supersymmetric standard model where the contributions to the EDM arise from the chargino and the neutralino exchanges in loops. Here it is shown that the electron EDM can probe mass scales from tens of TeV into the PeV range. The analysis is then extended to include a vectorlike generation which can mix with the three ordinary generations. Here new CP phases arise and it is shown that the electron EDM now has not only a supersymmetric (SUSY) contribution from the exchange of charginos and neutralinos but also a nonsupersymmetric contribution from the exchange of W and Z bosons. It is further shown that the interference of the supersymmetric and the nonsupersymmetric contribution leads to the remarkable phenomenon where the electron EDM as a function of the slepton mass first falls and become vanishingly small and then rises again as the slepton mass increases. This phenomenon arises as a consequence of cancellation between the SUSY and the non-SUSY contribution at low scales while at high scales the SUSY contribution dies out and the EDM is controlled by the non-SUSY contribution alone. The high mass scales that can be probed by the EDM are far in excess of what accelerators will be able to probe. The sensitivity of the EDM to CP phases both in the SUSY and the non-SUSY sectors are also discussed.

Ibrahim, Tarek; Itani, Ahmad; Nath, Pran

2014-09-01

460

Neutron and electron electric dipole moment in N=1 supergravity unification

An analysis of the neutron EDM and of the electron EDM in minimal N=1 supergravity unification with two CP-violating phases is given. For the neutron the analysis includes the complete one loop gluino, chargino, and neutralino exchange diagrams for the electric dipole and the chromoelectric dipole operators, and also the contribution of the purely gluonic dimension-six operator. It is shown that there exist significant regions in the six-dimensional parameter space of the model where cancellations between the gluino and the chargino exchanges reduce the electric and the chromoelectric contributions, and further cancellations among the electric, the chromoelectric, and the purely gluonic parts lead to a dramatic lowering of the neutron EDM sometimes below the electron EDM value. This phenomenon gives a new mechanism, i.e., that of internal cancellations, for the suppression of the neutron EDM in supersymmetric theories. The cancellation mechanism can significantly reduce the severe fine-tuning problem associated with CP-violating phases in SUSY and SUGRA unified models. {copyright} {ital 1997} {ital The American Physical Society}

Ibrahim, T.; Nath, P. [Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States)] [Department of Physics, Northeastern University, Boston, Massachusetts 02115 (United States)

1998-01-01

461

Full 180° Magnetization Reversal with Electric Fields

NASA Astrophysics Data System (ADS)

Achieving 180° magnetization reversal with an electric field rather than a current or magnetic field is a fundamental challenge and represents a technological breakthrough towards new memory cell designs. Here we propose a mesoscale morphological engineering approach to accomplishing full 180° magnetization reversals with electric fields by utilizing both the in-plane piezostrains and magnetic shape anisotropy of a multiferroic heterostructure. Using phase-field simulations, we examined a patterned single-domain nanomagnet with four-fold magnetic axis on a ferroelectric layer with electric-field-induced uniaxial strains. We demonstrated that the uniaxial piezostrains, if non-collinear to the magnetic easy axis of the nanomagnet at certain angles, induce two successive, deterministic 90° magnetization rotations, thereby leading to full 180° magnetization reversals.

Wang, J. J.; Hu, J. M.; Ma, J.; Zhang, J. X.; Chen, L. Q.; Nan, C. W.

2014-12-01

462

Full 180° magnetization reversal with electric fields.

Achieving 180° magnetization reversal with an electric field rather than a current or magnetic field is a fundamental challenge and represents a technological breakthrough towards new memory cell designs. Here we propose a mesoscale morphological engineering approach to accomplishing full 180° magnetization reversals with electric fields by utilizing both the in-plane piezostrains and magnetic shape anisotropy of a multiferroic heterostructure. Using phase-field simulations, we examined a patterned single-domain nanomagnet with four-fold magnetic axis on a ferroelectric layer with electric-field-induced uniaxial strains. We demonstrated that the uniaxial piezostrains, if non-collinear to the magnetic easy axis of the nanomagnet at certain angles, induce two successive, deterministic 90° magnetization rotations, thereby leading to full 180° magnetization reversals. PMID:25512070

Wang, J J; Hu, J M; Ma, J; Zhang, J X; Chen, L Q; Nan, C W

2014-01-01

463

Full 180° Magnetization Reversal with Electric Fields

Achieving 180° magnetization reversal with an electric field rather than a current or magnetic field is a fundamental challenge and represents a technological breakthrough towards new memory cell designs. Here we propose a mesoscale morphological engineering approach to accomplishing full 180° magnetization reversals with electric fields by utilizing both the in-plane piezostrains and magnetic shape anisotropy of a multiferroic heterostructure. Using phase-field simulations, we examined a patterned single-domain nanomagnet with four-fold magnetic axis on a ferroelectric layer with electric-field-induced uniaxial strains. We demonstrated that the uniaxial piezostrains, if non-collinear to the magnetic easy axis of the nanomagnet at certain angles, induce two successive, deterministic 90° magnetization rotations, thereby leading to full 180° magnetization reversals. PMID:25512070

Wang, J. J.; Hu, J. M.; Ma, J.; Zhang, J. X.; Chen, L. Q.; Nan, C. W.

2014-01-01

464

Microscopic calculations of the enhancement factor in the electric dipole sum rule

NASA Astrophysics Data System (ADS)

Correlated basis function perturbation theory with state-dependent correlations is used to calculate the nuclear photoabsorption enhancement factor K in the electric dipole sum rule for some realistic models of nuclear matter. The contribution due to 2p-2h admixtures in the ground state wave function turns out to be only a few percent of the unperturbed value. The values obtained for K are about 1.8 at experimental equilibrium density and increase almost linearly with density. We also give estimates of K for finite nuclei, obtained within the local density approximation framework. The surface effects give a contribution which is ? 20% of the volume term.

Fabrocini, A.; Lagaris, I. E.; Viviani, M.; Fantoni, S.

1985-06-01

465

Quantitative analysis of the electric dipole on finite sized graphite sheets

NASA Astrophysics Data System (ADS)

Graphite sheets are commonly used in introductory physics laboratories to model electric potential patterns for systems such as dipoles and parallel plates. Usually, silvered ink pens are used to draw patterns on the sheets and appropriate voltages are then applied. Quantitative experiments are often done at the intermediate level. Students are often puzzled by the failure of the patterns to confirm to the theoretical figure in the manual that came with the kit. I discuss measuring difficulties and some of the common theoretical methods for analyzing edge effects on the sheets.

Groh, David

2009-12-01

466

Microwave Spectra, Molecular Structure, and Electric Dipole Moment of 1,2-Dithiin

A pulsed-beam Fourier transform microwave spectrometer was used to investigate the rotational spectrum of 1,2-dithia-3,5-cyclohexadiene in the range 8 to 18 GHz. The observeda-type transitions were fit to a Watson asymmetric top Hamiltonian, giving the following rotational constants for the normal isotopomer:A= 3326.362(2) MHz,B= 3102.842(2) MHz,C= 1756.0026(7) MHz. An electric dipole moment of ?total= ?a= 1.850(1) D was determined from

J. Z. Gillies; C. W. Gillies; E. A. Cotter; E. Block; R. DeOrazio

1996-01-01

467

New concept for a neutron electric dipole moment search using a pulsed beam

NASA Astrophysics Data System (ADS)

A concept to search for a neutron electric dipole moment (nEDM) is presented, which employs a pulsed neutron beam instead of the established use of storable ultracold neutrons (UCN). The technique takes advantage of the high peak flux and the time structure of a next-generation pulsed spallation source like the planned European Spallation Source. It is demonstrated that the sensitivity for a nEDM can be improved by several orders of magnitude compared to the best beam experiments performed in the 1970s and can compete with the sensitivity of UCN experiments.

Piegsa, Florian M.

2013-10-01

468

Motivated by arguments of the nuclear core-layer model formulated in [S.I.\\u000aBastrukov, J.A. Maruhn, Z.Phys. A 335 (1990) 139], the macroscopic excitation\\u000amechanism of electric pygmy dipole resonance (PDR) is considered as owing its\\u000aorigin to perturbation-induced effective decomposition of nucleus into two\\u000aspherical domains - undisturbed inner region treated as static core and\\u000adynamical layer undergoing elastic shear vibrations.

S. I. Bastrukov; I. V. Molodtsova; S. Misicu; H. K. Chang; D. V. Podgainy

2008-01-01

469

Enhancement factor for the electron electric dipole moment in francium and gold atoms

If electrons had an electric dipole moment (EDM) they would induce EDMs of atoms. The ratio of the atomic EDM to the electron EDM for a particular atom is called the enhancement factor, R. We calculate the enhancement factor for the francium and gold atoms, with the results 910 plus/minus 5% for Fr and 260 plus/minus 15% for Au. The large values of these enhancement factors make these atoms attractive for electron EDM measurements, and hence the search for time-reversal invariance violation.

Byrnes, T M R; Flambaum, V V; Murray, D W

1998-01-01

470

NASA Astrophysics Data System (ADS)

Searching for a permanent electron electric dipole moment (EDM) is a powerful tool to probe for physics beyond the Standard Model. We identify the X^3?1 ground state of tungsten carbide molecules as a candidate system for the electron EDM search. We have developed a molecular beam source from pulse supersonic expansion technique and used laser induced fluorescence spectroscopy to detect the molecules through [20.6]?=2, v'=4 <-X^3?1,v"=0 transition. The beam properties, including the flux and internal temperature, are characterized. The hyperfine structure and the lambda doublet of the transition are measured and the implications related to the EDM experiment are revealed.

Lee, Jeongwon; Chen, Jinhai; Leanhardt, Aaron

2012-06-01

471

Electric Dipole Moments and the Mass Scale of New T-Violating, P-Conserving Interactions

We consider the implications of experimental limits on the permanent electric dipole moment (EDM) of the electron and neutron for possible new time-reversal violating (TV) parity-conserving (PC) interactions. We show that the constraints derived from one-loop contributions to the EDM exceed previously reported two-loop limits by more than an order of magnitude and imply a lower bound on the new TVPC mass scale Lambda{sub TVPC} of 150 TeV for new TVPC strong interactions. These results imply a value of 10{sup -15} or smaller for the ratio of low energy TVPC matrix elements to those of the residual strong interaction.

Michael J. Ramsey-Musolf

1999-11-15

472

Energies and Electric Dipole Transitions for Low-Lying Levels of Protactinium IV and Uranium V

NASA Astrophysics Data System (ADS)

We have reported a relativistic multiconfiguration Dirac-Fock (MCDF) study on low-lying level structures of protactinium IV (Z =91) and uranium V (Z =92) ions. Excitation energies and electric dipole (E1) transition parameters (wavelengths, oscillator strengths, and transition rates) for these low-lying levels have been given. We have also investigated the influence of the transverse Breit and quantum electrodynamic (QED) contributions besides correlation effects on the level structure. A comparison has been made with a few available data for these ions in the literature.

Ürer, Güldem; Özdemir, Leyla

2012-02-01

473

Electron and neutron electric dipole moment in the 3-3-1 model with heavy leptons

NASA Astrophysics Data System (ADS)

We calculate the electric dipole moment for the electron and neutron in the framework of the 3-3-1 model with heavy charged leptons. We assume that the only source of C P violation arises from a complex trilinear coupling constant and the three complex vacuum expectation values. However, two of the vacua phases are absorbed and the other two are equal up to a minus sign. Hence only one physical phase survives. In order to be compatible with the experimental data this phase has to be smaller than 1 0-6.

De Conto, G.; Pleitez, V.

2015-01-01

474

Design for a fountain of YbF molecules to measure the electron's electric dipole moment

NASA Astrophysics Data System (ADS)

We propose an experiment to measure the electric dipole moment (EDM) of the electron using ultracold YbF molecules. The molecules are produced as a thermal beam by a cryogenic buffer gas source, and brought to rest in an optical molasses that cools them to the Doppler limit or below. The molecular cloud is then thrown upward to form a fountain in which the EDM of the electron is measured. A non-zero result would be unambiguous proof of new elementary particle interactions, beyond the standard model.

Tarbutt, M. R.; Sauer, B. E.; Hudson, J. J.; Hinds, E. A.

2013-05-01

475

Performance of six 4. 5 m SSC (Superconducting Super Collider) dipole model magnets

Six 4.5 m long dipole models for the proposed Superconducting Super Collider have been successfully tested. The magnets are cold-iron (and cold bore) 1-in-1 dipoles, wound with current density-graded high homogeneity NbTi cable in a two-layer cos theta coil of 40 mm inner diameter. The coil is prestressed by 15 mm wide stainless steel collars, and mounted in a circular, split iron yoke of 267 mm outer diameter, supported in a cylindrical yoke containment vessel. At 4.5 K the magnets reached a field of about 6.6 T with little training, or the short sample limit of the conductor, and in subcooled (2.6 - 2.4 K) liquid, 8 T was achieved. The allowed harmonics were close to the predicted values, and the unallowed harmonics small. The sextupole trim coil operated well above the required current with little training.

Willen, E.; Dahl, P.; Cottingham, J.; Garber, M.; Ghosh, A.; Goodzeit, C.; Green, A.; Herrera, J.; Kahn, S.; Kelly, E.

1986-01-01

476

Holographic Aspects of Electric-Magnetic Dualities

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.

Sebastian de Haro; Anastasios C. Petkou

2007-10-04

477

Magnetic dipole lines in the 3s23px configurations of elements from copper to molybdenum

A number of spectrum lines arising from magnetic dipole transitions in the 3s23p5, 3s23p4, 3s23p3, 3s23p2, 3s23p, and 3s 3p electron configurations in elements 29<=Z<=42 have been identified. The lines were observed in the Princeton Large Torus tokamak discharges into which the appropriate elements were introduced by means of laser blowoff. The identifications are based on time and space dependence

B. Denne; E. Hinnov; S. Suckewer; S. Cohen

1983-01-01

478

Measurements of electron cloud growth and mitigation in dipole, quadrupole, and wiggler magnets

NASA Astrophysics Data System (ADS)

Retarding field analyzers (RFAs), which provide a localized measurement of the electron cloud, have been installed throughout the Cornell Electron Storage Ring (CESR), in different magnetic field environments. This paper describes the RFA designs developed for dipole, quadrupole, and wiggler field regions, and provides an overview of measurements made in each environment. The effectiveness of electron cloud mitigations, including coatings, grooves, and clearing electrodes, are assessed with the RFA measurements.

Calvey, J. R.; Hartung, W.; Li, Y.; Livezey, J. A.; Makita, J.; Palmer, M. A.; Rubin, D.

2015-01-01

479

SQUIDs as detectors in a new experiment to measure the neutron electric dipole moment

A new experiment has been proposed at Los Alamos National Laboratory to measure the neutron electric dipole moment (EDM) to 4{times}10{sup {minus}28} ecm, a factor of 250 times better than the current experimental limit. Such a measure of the neutron EDM would challenge the theories of supersymmetry and time reversal violation as the origin of the observed cosmological asymmetry in the ratio of baryons to antibaryons. One possible design for this new experiment includes the use of LTC SQUIDs coupled to large ({approximately}100 cm{sup 2}) pick-up coils to measure the precision frequency of the spin-polarized {sup 3}He atoms that act as polarizer, spin analyzer, detector, and magnetometer for the ultra-cold neutrons used in the experiment. The method of directly measuring the {sup 3}He precession signal eliminates the need for very uniform magnetic fields (a major source of systematic error in these types of experiments). It is estimated that a flux of {approximately}2{times}10{sup {minus}16} Tm{sup 2} (0.1 {Phi}{sub 0}) will be coupled into the pick-up coils. To achieve the required signal-to-noise ratio one must have a flux resolution of d{Phi}{sub SQ} = 2{times}10{sup {minus}6}{Ph