Sample records for dipole magnet system

  1. The dipole corrector magnets for the RHIC fast global orbit feedback system

    SciTech Connect (OSTI)

    Thieberger, P.; Arnold, L.; Folz, C.; Hulsart, R.; Jain, A.; Karl, R.; Mahler, G.; Meng, W.; Mernick, K.; Michnoff, R.; Minty, M.; Montag, C.; Ptitsyn, V.; Ritter, J.; Smart, L.; Tuozzolo, J.; White, J.

    2011-03-28T23:59:59.000Z

    The recently completed RHIC fast global orbit feedback system uses 24 small 'window-frame' horizontal dipole correctors. Space limitations dictated a very compact design. The magnetic design and modelling of these laminated yoke magnets is described as well as the mechanical implementation, coil winding, vacuum impregnation, etc. Test procedures to determine the field quality and frequency response are described. The results of these measurements are presented and discussed. A small fringe field from each magnet, overlapping the opposite RHIC ring, is compensated by a correction winding placed on the opposite ring's magnet and connected in series with the main winding of the first one. Results from measurements of this compensation scheme are shown and discussed.

  2. Electric Dipole Moment of Magnetic Monopole

    E-Print Network [OSTI]

    Makoto Kobayashi

    2007-03-07T23:59:59.000Z

    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).

  3. Magnetic dipole discharges. III. Instabilities

    SciTech Connect (OSTI)

    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)

    2013-08-15T23:59:59.000Z

    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.

  4. Capacitive Stress Transducers in Model Dipole Magnets

    E-Print Network [OSTI]

    Benson, Christopher P.

    2010-07-14T23:59:59.000Z

    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...

  5. PERFORMANCE OF DIPOLE MAGNETS IN HELIUM II

    E-Print Network [OSTI]

    Althaus, R.

    2010-01-01T23:59:59.000Z

    in Pressurized Superfluid Helium", EX5 40 11th InternationalOF DIPOLE MAGNETS IN HELIUM II R. Althaus, S. Cacpi, W.S.OF DIMLE NMMETS IN HELIUM II* R. Althaus, S. Caspl, W.S.

  6. SSC collider dipole magnet end mechanical design

    SciTech Connect (OSTI)

    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))

    1991-05-01T23:59:59.000Z

    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.

  7. Instantaneous Power Radiated from Magnetic Dipole Moments

    E-Print Network [OSTI]

    Peter D. Morley; Douglas J. Buettner

    2014-07-04T23:59:59.000Z

    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.

  8. A 6.4 TESLA DIPOLE MAGNET FOR THE SSC

    E-Print Network [OSTI]

    Taylor, C.E.

    2010-01-01T23:59:59.000Z

    Engineering, Volume 31 A 6.4 TESLA DIPOLE MAGNET FOR THE SSCR. SCANLAN SSC-MAG A 6.4 TESLA DIPOLE MAGiET FOR THE SSC* C.increa.ing up to . 28 tesla . - The resultins systematic

  9. arc dipole magnets: Topics by E-print Network

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

    R&D on a fast cycled superconducting dipole magnet (FCM) of interest for the upgrade plan of the LHC accelerator complex. The FCM dipole prototype being built has a number of...

  10. Magnet end design: The main injector dipoles

    SciTech Connect (OSTI)

    Ostiguy, J.F.

    1991-08-01T23:59:59.000Z

    From the accelerator designer standpoint, one of the quantities of interest in a magnet is the axially integrated transverse field. It is easily shown that the latter satisfies the equations of 2D magnetostatics. This is the basic theoretical result needed to design accelerator magnet ends. Unfortunately, axially integrated fields must be obtained from accurate 3D field maps and magnets ends have historically been designed using a cut and try approach. To a certain extent, this remains true even today; however, the advent of reliable 3D magnet design codes now permits to substantially reduce the costs associated with the construction of various prototypes. In this paper, the theory of magnet end design is reviewed. The design of the end of the dipole magnets of the proposed Fermilab Main Injector is analyzed in a detailed manner using TOSCA, a well-established 3D finite element code. Provided the limitations of the code are well understood by the user, the integrated field profile is satisfactorily predicted.

  11. Plasma expansion in the presence of a dipole magnetic field

    SciTech Connect (OSTI)

    Winske, D.; Omidi, N. [Applied Physics Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); SciberNet, Inc., Solana Beach, California 92075 (United States)

    2005-07-15T23:59:59.000Z

    Simulations of the initial expansion of a plasma injected into a stationary magnetized background plasma in the presence of a dipole magnetic field are carried out in two dimensions with a kinetic ion, massless fluid electron (hybrid) electromagnetic code. For small values of the magnetic dipole, the injected ions have large gyroradii compared to the scale length of the dipole field and are essentially unmagnetized. As a result, these ions expand, excluding the ambient magnetic field and plasma to form a diamagnetic cavity. However, for stronger magnetic dipoles, the ratio of the gyroradii of the injected ions to the dipole field scale length is small so that they remain magnetized, and hence trapped in the dipole field, as they expand. The trapping and expansion then lead to additional plasma currents and resulting magnetic fields that not only exclude the background field but also interact with the dipole field in a more complex manner that stretches the closed dipole field lines. A criterion to distinguish between the two regimes is derived and is then briefly discussed in the context of applying the results to the plasma sail scheme for the propulsion of small spacecraft in the solar wind.

  12. Performance analysis of HD1: a 16 Tesla Nb3Sn dipole Magnet

    E-Print Network [OSTI]

    Mattafirri, S.

    2009-01-01T23:59:59.000Z

    Analysis of HD1: A 16 Tesla Nb 3 Sn Dipole Magnet S.of HD1b, an Upgraded 16 Tesla Nb 3 Sn Dipole Magnet”, This

  13. Ground State of Magnetic Dipoles on a Two-Dimensional Lattice: Structural Phases in Complex Plasmas

    SciTech Connect (OSTI)

    Feldmann, J. D.; Kalman, G. J. [Department of Physics, Boston College, 140 Commonwealth Avenue, Chestnut Hill, Massachusetts, 02467 (United States); Hartmann, P. [Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary); Rosenberg, M. [Department of Electrical and Computer Engineering, University of California-San Diego, La Jolla, California, 92093 (United States)

    2008-02-29T23:59:59.000Z

    We study analytically and by molecular dynamics simulations the ground state configuration of a system of magnetic dipoles fixed on a two-dimensional lattice. We find different phases, in close agreement with previous results. Building on this result and on the minimum energy requirement we determine the equilibrium lattice configuration, the magnetic order (ferromagnetic versus antiferromagnetic), and the magnetic polarization direction of a system of charged mesoscopic particles with magnetic dipole moments, in the domain where the strong electrostatic coupling leads to a crystalline ground state. Orders of magnitudes of the parameters of the system relevant to possible future dusty plasma experiments are discussed.

  14. Equilibrium and stability studies of plasmas confined in a dipole magnetic field using magnetic measurements

    E-Print Network [OSTI]

    Karim, Ishtak

    2007-01-01T23:59:59.000Z

    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 ...

  15. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, W.F.

    1983-08-31T23:59:59.000Z

    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.

  16. Dual aperture dipole magnet with second harmonic component

    DOE Patents [OSTI]

    Praeg, Walter F. (Palos Park, IL)

    1985-01-01T23:59:59.000Z

    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.

  17. Regular and chaotic dynamics of a chain of magnetic dipoles with moments of inertia

    SciTech Connect (OSTI)

    Shutyi, A. M. [Ulyanovsk State University (Russian Federation)], E-mail: shuty@mail.ru

    2009-05-15T23:59:59.000Z

    The nonlinear dynamic modes of a chain of coupled spherical bodies having dipole magnetic moments that are excited by a homogeneous ac magnetic field are studied using numerical analysis. Bifurcation diagrams are constructed and used to find conditions for the presence of several types of regular, chaotic, and quasi-periodic oscillations. The effect of the coupling of dipoles on the excited dynamics of the system is revealed. The specific features of the Poincare time sections are considered for the cases of synchronous chaos with antiphase synchronization and asynchronous chaos. The spectrum of Lyapunov exponents is calculated for the dynamic modes of an individual dipole.

  18. Test Results for HD1, a 16 Tesla Nb3Sn Dipole Magnet

    E-Print Network [OSTI]

    Lietzke, A.F.

    2011-01-01T23:59:59.000Z

    Design and Fabrication ofa 16 Tesla Nb 3 Sn Dipole Magnet",Test Results for HD 1, a 16 Tesla Nb 3 Sn Dipole Magnet A.F.and bore fields above 16 Tesla. II. MAGNET FEATURES AND TEST

  19. The magnetic dipole interaction in Einstein-Maxwell theory

    E-Print Network [OSTI]

    W. B. Bonnor

    2002-03-13T23:59:59.000Z

    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.

  20. Constraining the neutrino magnetic dipole moment from white dwarf pulsations

    E-Print Network [OSTI]

    Córsico, Alejandro H; Bertolami, Marcelo M Miller; Kepler, S O; García-Berro, Enrique

    2014-01-01T23:59:59.000Z

    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. By comparing the theoretical rate of change of period expected for this star 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. Our upper limit for the neutrino magnetic dipole moment is somewhat less restrictive than, but still compat...

  1. Floating coil position detection system for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Roach, Austin Hayes

    2005-01-01T23:59:59.000Z

    The Levitated Dipole Experiment (LDX) is a joint Columbia University/MIT research collaboration sited at MIT's Plasma Science and Fusion Center. LDX is investigating the physics of a plasma confined in a dipole magnetic ...

  2. Anomalous Magnetic and Electric Dipole Moments of the Tau

    E-Print Network [OSTI]

    Lucas Taylor

    1998-10-23T23:59:59.000Z

    This paper reviews the theoretical predictions for and the experimental measurements of the anomalous magnetic and electric dipole moments of the tau lepton. In particular, recent analyses of the $\\eettg$ process from the L3 and OPAL collaborations are described. The most precise results, from L3, for the anomalous magnetic and electric dipole moments respectively are: $\\atau = 0.004 \\pm 0.027 \\pm 0.023$ and $\\dtau = (0.0 \\pm 1.5 \\pm 1.3)\\times 10^{-16}{e{\\cdot}\\mathrm{cm}}$.

  3. DESIGN OF A 10-T SUPERCONDUCTING DIPOLE MAGNET USING NIOBIUM-TIN CONDUCTOR

    E-Print Network [OSTI]

    Taylor, C.

    2011-01-01T23:59:59.000Z

    DIPOLE HAGNET USING NIOBIUM-TIN CONOOCTOR' C. Taylor, R.DIPOLE MAGNET USING NIOBIUM-TIN CONDUCTOR C. Taylor, R.slid tooling for the niobium- tin magnet .sre on halld, and

  4. MAGNETIC DESIGN OF DIPOLES FOR LHC INSERTION REGIONS* A. Jain, R. Gupta

    E-Print Network [OSTI]

    Gupta, Ramesh

    MAGNETIC DESIGN OF DIPOLES FOR LHC INSERTION REGIONS* A. Jain, R. Gupta 1 , P. Wanderer, E. Willen) will be built at BNL. All these magnets will have the 80 mm aperture coil design used for the RHIC arc dipoles as single aperture magnets with the same yoke design as the RHIC arc dipoles. The expected field quality

  5. Capacitive Stress Gauges in Model Dipole Magnets

    E-Print Network [OSTI]

    Ragland, R. Blake

    2009-06-09T23:59:59.000Z

    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...

  6. Refrigeration options for the Advanced Light Source Superbend Dipole Magnets

    SciTech Connect (OSTI)

    Green, M.A.; Hoyer, E.H.; Schlueter, R.D.; Taylor, C.E.; Zbasnik, J.; Wang, S.T.

    1999-07-09T23:59:59.000Z

    The 1.9 GeV Advance Light Source (ALS) at the Lawrence Berkeley National Laboratory (LBNL) produces photons with a critical energy of about 3.1 kev at each of its thirty-six 1.3 T gradient bending magnets. It is proposed that at three locations around the ring the conventional gradient bending magnets be replaced with superconducting bending magnets with a maximum field of 5.6 T. At the point where the photons are extracted, their critical energy will be about 12 keV. In the beam lines where the SuperBend superconducting magnets are installed, the X ray brightness at 20 keV will be increased over two orders of magnitude. This report describes three different refrigeration options for cooling the three SuperBend dipoles. The cooling options include: (1) liquid helium and liquid nitrogen cryogen cooling using stored liquids, (2) a central helium refrigerator (capacity 70 to 100 W) cooling all of the SuperBend magnets, (3) a Gifford McMahon (GM) cryocooler on each of the dipoles. This paper describes the technical and economic reasons for selecting a small GM cryocooler as the method for cooling the SuperBend dipoles on the LBNL Advanced Light Source.

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

    SciTech Connect (OSTI)

    Nicol, T.H.

    1989-09-01T23:59:59.000Z

    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.

  8. DESIGN STUDY OF THE DIPOLE MAGNET FOR THE RHIC EBIS HIGH ENERGY TRANSPORT LINE

    E-Print Network [OSTI]

    DESIGN The bending section in EBIS HEBT line consists of two identical H type magnets with a slit betweenDESIGN STUDY OF THE DIPOLE MAGNET FOR THE RHIC EBIS HIGH ENERGY TRANSPORT LINE Takeshi Kanesue magnet body should be laminated. In this paper, design methods of the dipole magnet to optimize magnetic

  9. Dynamics of two-dimensional dipole systems

    SciTech Connect (OSTI)

    Golden, Kenneth I.; Kalman, Gabor J.; Hartmann, Peter; Donko, Zoltan [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401 (United States); Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States); Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest, Hungary and Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States)

    2010-09-15T23:59:59.000Z

    Using a combined analytical/molecular dynamics approach, we study the current fluctuation spectra and longitudinal and transverse collective mode dispersions of the classical two-dimensional (point) dipole system (2DDS) characterized by the {phi}{sub D}(r)={mu}{sup 2}/r{sup 3} repulsive interaction potential; {mu} is the electric dipole strength. The interest in the 2DDS is twofold. First, the quasi-long-range 1/r{sup 3} interaction makes the system a unique classical many-body system, with a remarkable collective mode behavior. Second, the system may be a good model for a closely spaced semiconductor electron-hole bilayer, a system that is in the forefront of current experimental interest. The longitudinal collective excitations, which are of primary interest for the liquid phase, are acoustic at long wavelengths. At higher wave numbers and for sufficiently high coupling strength, we observe the formation of a deep minimum in the dispersion curve preceded by a sharp maximum; this is identical to what has been observed in the dispersion of the zero-temperature bosonic dipole system, which in turn emulates so-called roton-maxon excitation spectrum of the superfluid {sup 4}He. The analysis we present gives an insight into the emergence of this apparently universal structure, governed by strong correlations. We study both the liquid and the crystalline solid state. We also observe the excitation of combination frequencies, resembling the roton-roton, roton-maxon, etc. structures in {sup 4}He.

  10. Generalized dyons and magnetic dipoles: the issue of angular momentum

    E-Print Network [OSTI]

    Francisco Navarro-Lerida; Eugen Radu; D. H. Tchrakian

    2014-07-12T23:59:59.000Z

    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 behaviour 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.

  11. Torsional Oscillations of Relativistic Stars with Dipole Magnetic Fields

    E-Print Network [OSTI]

    H. Sotani; K. D. Kokkotas; N. Stergioulas

    2007-10-11T23:59:59.000Z

    We present the formalism and numerical results for torsional oscillations of relativistic stars endowed with a strong dipole magnetic field. We do a systematic search of parameter space by computing torsional mode frequencies for various values of the harmonic index $\\ell$ and for various overtones, using an extended sample of models of compact stars, varying in mass, high-density equation of state and crust model. We show that torsional mode frequencies are sensitive to the crust model if the high-density equation of state is very stiff. In addition, torsional mode frequencies are drastically affected by a dipole magnetic field, if the latter has a strength exceeding roughly $10^{15}$G and we find that the magnetic field effects are sensitive to the adopted crust model. Using our extended numerical results we derive empirical relations for the effect of the magnetic field on torsional modes as well as for the crust thickness. We compare our numerical results to observed frequencies in SGRs and find that certain high-density EoS and mass values are favored over others in the non-magnetized limit. On the other hand, if the magnetic field is strong, then its effect has to be taken into account in attempts to formulate a theory of asteroseismology for magnetars.

  12. Interaction between an electric charge and a magnetic dipole of any kind (permanent, para- or dia- magnetic or superconducting)

    E-Print Network [OSTI]

    Coďsson, R

    2015-01-01T23:59:59.000Z

    The interaction between point charge and magnetic dipole is usually considered only for the case of a rigid ferromagnetic dipole (constant-current): here the analysis of force, momentum and energy (including the energy provided by the internal current generator) is generalised to any magnetic dipole behaviour: rigid, paramagnetic, diamagnetic or superconducting (perfectly diamagnetic).

  13. A superconducting dipole magnet for laser spectroscopy

    E-Print Network [OSTI]

    Wagenhauser, Kenneth Edward

    1990-01-01T23:59:59.000Z

    while heated, and later reached 5 x 10-7 torr with the cryostat cooled and liquid helium in the helium vessel. Initial static testing of the vacuum vessel showed a leak of 0. 2 microns per hour, which suggests the use of a turbopump to maintain... specifications. . . . . . . . . . . . . Mass of system components. . Calibration of the liquid helium level sensor. . . . . . . . . . . . . . . . . . . . . Enthalpies of cryostat components. . Estimates of heat input. Heat input test results. Measured...

  14. Dual AC Dipole Excitation for the Measurement of Magnetic Multipole Strength from Beam Position Monitor Data

    SciTech Connect (OSTI)

    M. Spata, G.A. Krafft

    2011-09-01T23:59:59.000Z

    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.

  15. The atomic electric dipole moment induced by the nuclear electric dipole moment; the magnetic moment effect

    E-Print Network [OSTI]

    Porsev, S G; Flambaum, V V

    2010-01-01T23:59:59.000Z

    We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.

  16. The atomic electric dipole moment induced by the nuclear electric dipole moment; the magnetic moment effect

    E-Print Network [OSTI]

    S. G. Porsev; J. S. M. Ginges; V. V. Flambaum

    2011-03-02T23:59:59.000Z

    We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.

  17. 6. 4 Tesla dipole magnet for the SSC

    SciTech Connect (OSTI)

    Taylor, C.E.; Caspi, S.; Gilbert, W.; Meuser, R.; Mirk, K.; Peters, C.; Scanlan, R.; Dahl, P.; Cottingham, J.; Hassenzahl, W.

    1985-05-01T23:59:59.000Z

    A design is presented for a dipole magnet suitable for the proposed SSC facility. Test results are given for model magnets of this design 1 m long and 4.5 m long. Flattened wedge-shaped cables (''keystoned'') are used in a graded, two-layer ''cos theta'' configuration with three wedges to provide sufficient field uniformity and mechanical rigidity. Stainless steel collars 15 mm wide, fastened with rectangular keys, provide structural support, and there is a ''cold'' iron flux return. The outer-layer cable has 30 strands of 0.0255 in. dia NbTi multifilamentary wire with Cu/S.C. = 1.8, and the inner has 23 strands of .0318 in. dia wire with Cu/S.C. = 1.3. Performance data is given including training behavior, winding stresses, collar deformation, and field uniformity.

  18. HD1: Design and Fabrication of a 16 Tesla Nb3Sn Dipole Magnet

    E-Print Network [OSTI]

    Hafalia, A.R.

    2011-01-01T23:59:59.000Z

    and Fabrication of a 16 Tesla Nb 3 Sn Dipole Magnet A .R.ge nerating fields above 16 Tesla in practical acceleratordesign fields above 10 Tesla. In a series of magnet tests,

  19. Ramp-rate sensitivity of SSC dipole magnet prototypes

    SciTech Connect (OSTI)

    Devred, A.; Ogitsu, T.

    1994-07-01T23:59:59.000Z

    One of the major achievements of the magnet R&D program for the Superconducting Super Collider (SSC) is the fabrication and test of a series of 20 5-cm aperture, 15-m long dipole magnet prototypes. The ramp rate sensitivity of these magnets appears to fall in at least two categories that can be correlated to the manufacturer and production batch of the strands used for the inner-coil cables. The first category, referred to as type-A, is characterized by a strong quench current degradation at high ramp rates, usually accompanied by large distortions of the multipole fields and large energy losses. The second category, referred to as type-B, is characterized by a sudden drop of quench current at low ramp rates, followed by a much milder degradation at larger rates. The multipole fields of the type-B magnets show little ramp-rate sensitivity, and the energy losses are smaller than for the type-A magnets. The behavior of the Type-A magnets can be explained in terms of inter-strand eddy currents arising from low and non-uniform resistances at the crossovers between the strands of the two-layer Rutherford-type cable. Anomalies in the transport-current repartition among the cable strands are suggested as a possible cause for the type-B behavior. The origins of these anomalies have not yet been clearly identified. The SSC project was canceled by decision of the United States Congress on October 21, 1994.

  20. Contamination of Dark Matter Experiments from Atmospheric Magnetic Dipoles

    E-Print Network [OSTI]

    A. Bueno; M. Masip; P. Sánchez-Lucas; N. Setzer

    2013-10-14T23:59:59.000Z

    Dark matter collisions with heavy nuclei (Xe, Ge, Si, Na) may produce recoils observable at direct-search experiments. Given that some of these experiments are yielding conflicting information, however, it is worth asking if physics other than dark matter may produce similar nuclear recoils. We examine under what conditions an atmospherically-produced neutral particle with a relatively large magnetic dipole moment could fake a dark matter signal. We argue that a very definite flux could explain the signals seen at DAMA/LIBRA, CDMS/Si and CoGeNT consistently with the bounds from XENON100 and CDMS/Ge. To explore the plausibility of this scenario, we discuss a concrete model with 10-50 MeV sterile neutrinos that was recently proposed to explain the LSND and MiniBooNE anomalies.

  1. ANALYTICAL CALCULATION OF STOKES PROFILES OF ROTATING STELLAR MAGNETIC DIPOLE

    SciTech Connect (OSTI)

    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)

    2012-08-20T23:59:59.000Z

    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.

  2. Radiation effects in a muon collider ring and dipole magnet protection

    E-Print Network [OSTI]

    Mokhov, N V; Novitski, I; Zlobin, A V

    2011-01-01T23:59:59.000Z

    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 1034 cm-2s-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.

  3. AC magnetic measurements of the ALS Booster Dipole Engineering Model Magnet

    SciTech Connect (OSTI)

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

    1989-03-01T23:59:59.000Z

    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.

  4. Electric and Magnetic Dipoles in the Lorentz and Einstein-Laub Formulations of Classical Electrodynamics

    E-Print Network [OSTI]

    Mansuripur, Masud

    2015-01-01T23:59:59.000Z

    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...

  5. Stable High Beta Plasmas Confined by a Dipole Magnetic Field D. T. Garnier,

    E-Print Network [OSTI]

    Mauel, Michael E.

    Stable High Beta Plasmas Confined by a Dipole Magnetic Field D. T. Garnier, A. Hansen, M. E. Mauel Center, MIT, Cambridge, MA 02139 (Dated: October 21, 2005) Abstract Stable high-beta plasma is created we report the first production of high beta plasma confined by a laboratory dipole using neutral gas

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

    SciTech Connect (OSTI)

    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

    2007-06-01T23:59:59.000Z

    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.

  7. Artificial light and quantum order in systems of screened dipoles

    E-Print Network [OSTI]

    Xiao-Gang Wen

    2003-04-14T23:59:59.000Z

    The origin of light is a unsolved mystery in nature. Recently, it was suggested that light may originate from a new kind of order - quantum order. To test this idea in experiments, we study systems of screened magnetic/electric dipoles in 2D and 3D lattices. We show that our models contain an artificial light -- a photon-like collective excitation. We discuss how to design realistic devices that realize our models. We show that the ``speed of light'' and the ``fine structure constant'' of the artificial light can be tuned in our models. The properties of artificial atoms (bound states of pairs of artificial charges) are also discussed. The existence of artificial light (as well as artificial electron) in condensed matter systems suggests that elementary particles, such as light and electron, may not be elementary. They may be collective excitations of quantum order in our vacuum. Our models further suggest that a gauge theory is a string-net theory in disguise. Light is a fluctuation of nets of large closed strings and charge is the end of open strings.

  8. TOSCA calculations and measurements for the SLAC SLC damping ring dipole magnet

    SciTech Connect (OSTI)

    Early, R.A.; Cobb, J.K.

    1985-04-01T23:59:59.000Z

    The SLAC damping ring dipole magnet was originally designed with removable nose pieces at the ends. Recently, a set of magnetic measurements was taken of the vertical component of induction along the center of the magnet for four different pole-end configurations and several current settings. The three dimensional computer code TOSCA, which is currently installed on the National Magnetic Fusion Energy Computer Center's Cray X-MP, was used to compute field values for the four configurations at current settings near saturation. Comparisons were made for magnetic induction as well as effective magnetic lengths for the different configurations. 1 ref., 12 figs., 2 tabs.

  9. Radiation effects in a muon collider ring and dipole magnet protection

    SciTech Connect (OSTI)

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

    2011-03-01T23:59:59.000Z

    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.

  10. Submitted to MT-15, Fifteenth International Conference on Magnet Technology, Beijing, China, October 20-24, 1997. Coldmass for LHC Dipole Insertion Magnets*

    E-Print Network [OSTI]

    Ohta, Shigemi

    designed with 2-in-1 coldmasses. In the design presented here, all magnets would be 2-in-1 type coldmasses and the expected field quality in 2-in-1 dipole magnets. A unique feature of this coldmass design is the use design and allows the LHC main dipole cryostat, post, etc., to be used in these magnets. The pro- posed

  11. Fabrication and Test Results of a Nb3Sn Superconducting Racetrack Dipole Magnet

    SciTech Connect (OSTI)

    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.

    2000-02-06T23:59:59.000Z

    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.

  12. Charged spinning fluids with magnetic dipole moment in the Einstein-Cartan theory

    SciTech Connect (OSTI)

    Amorim, R.

    1985-06-15T23:59:59.000Z

    A classical perfect charged spinning fluid with magnetic dipole moment in the Einstein-Cartan theory is described by using an Eulerian Lagrangian formalism. The field equations and equations of motion so obtained generalize those proposed by Ray and Smalley. We also clarify some open questions which appear in the works of Ray and Smalley and of de Ritis et al.

  13. Experimental evaluation of vertically versus horizontally split yokes for SSC (Superconducting Super Collider) dipole magnets

    SciTech Connect (OSTI)

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

    1990-05-03T23:59:59.000Z

    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.

  14. Test Results of HD1b, an upgraded 16 Tesla Nb3Sn DipoleMagnet

    SciTech Connect (OSTI)

    Lietzke, A.F.; Bartlett, S.E.; Bish, P.; Caspi, S.; Dietderich,D.; Ferracin, P.; Gourlay, S.; Hafalia, A.R.; Hannaford, C.R.; Higley,H.; Lau, W.; Liggins, N.; Mattafirri, S.; Nyman, M.; Sabbi, G.; Scanlan,R.; Swanson, J.

    2005-04-16T23:59:59.000Z

    The Superconducting Magnet Group at Lawrence Berkeley National Laboratory has been developing high-field, brittle-superconductor, accelerator magnet technology, in which the conductor's support system can significantly impact conductor performance (as well as magnet training). A recent H-dipole coil test (HD1) achieved a peak bore-field of 16 Tesla, using two, flat-racetrack, double-layer Nb{sub 3}Sn coils. However, its 4.5 K training was slow, with an erratic plateau at {approx}92% of its un-degraded ''short-sample'' expectation ({approx}16.6 T). Quench-origins correlated with regions where low conductor pre-stress had been expected (3-D FEM predictions and variations in 300 K coil-size). The coils were re-assembled with minor coil-support changes and re-tested as ''HD1b'', with a 185 MPa average pre-stress (30 MPa higher than HD1, with a 15-20 MPa pole-turn margin expected at 17 T). Training started higher (15.1 T), and quickly reached a stable, negligibly higher plateau at 16 T. After a thermal cycle, training started at 15.4 T, but peaked at 15.8 T, on the third attempt, before degrading to a 15.7 T plateau. The temperature dependence of this plateau was explored in a sub-atmospheric LHe bath to 3.0 K. Magnet performance data for both thermal cycles is presented and discussed, along with issues for future high-field accelerator magnet development.

  15. A POUR IAYER, TWO INCH BORE, SUPERCONDUCTING DIPOLE MAGNET

    E-Print Network [OSTI]

    Hassenzahl, W.V.

    2011-01-01T23:59:59.000Z

    C. Peters, W. Gilbert, C. Taylor and R. M user e LawrencePeters, W. Gilbert, C. Taylor, and R. Meuser November 19829A magnet. References I. C. Taylor, R. Meuser, S. Caspl, W.

  16. Studies of time dependence of fields in TEVATRON superconducting dipole magnets

    SciTech Connect (OSTI)

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

    1988-08-22T23:59:59.000Z

    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.

  17. Discrete Symmetries on the Light Front and a General Relation connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    SciTech Connect (OSTI)

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

    2006-01-11T23:59:59.000Z

    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}.

  18. Discrete symmetries on the light front and a general relation connecting the nucleon electric dipole and anomalous magnetic moments

    SciTech Connect (OSTI)

    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)

    2006-02-01T23:59:59.000Z

    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}.

  19. Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    E-Print Network [OSTI]

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

    2006-02-27T23:59:59.000Z

    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.

  20. Acoustic dispersion in a two-dimensional dipole system

    SciTech Connect (OSTI)

    Golden, Kenneth I.; Kalman, Gabor J.; Donko, Zoltan; Hartmann, Peter [Department of Mathematics and Statistics, College of Engineering and Mathematical Sciences, University of Vermont, Burlington, Vermont 05401-1455 (United States); Department of Physics, Boston College, Chestnut Hill, Massachusetts 02467 (United States); Research Institute for Solid State Physics and Optics of the Hungarian Academy of Sciences, P.O. Box 49, H-1525 Budapest (Hungary)

    2008-07-15T23:59:59.000Z

    We calculate the full density response function and from it the long-wavelength acoustic dispersion for a two-dimensional system of strongly coupled point dipoles interacting through a 1/r{sup 3} potential at arbitrary degeneracy. Such a system has no random-phase-approximation (RPA) limit and the calculation has to include correlations from the outset. We follow the quasilocalized charge (QLC) approach, accompanied by molecular-dynamics (MD) simulations. Similarly to what has been recently reported for the closely spaced classical electron-hole bilayer [G. J. Kalman et al., Phys. Rev. Lett. 98, 236801 (2007)] and in marked contrast to the RPA, we report a long-wavelength acoustic phase velocity that is wholly maintained by particle correlations and varies linearly with the dipole moment p. The oscillation frequency, calculated both in an extended QLC approximation and in the Singwi-Tosi-Land-Sjolander approximation [Phys. Rev. 176, 589 (1968)], is invariant in form over the entire classical to quantum domains all the way down to zero temperature. Based on our classical MD-generated pair distribution function data and on ground-state energy data generated by recent quantum Monte Carlo simulations on a bosonic dipole system [G. E. Astrakharchik et al., Phys. Rev. Lett. 98, 060405 (2007)], there is a good agreement between the QLC approximation kinetic sound speeds and the standard thermodynamic sound speeds in both the classical and quantum domains.

  1. Design study of 15-Tesla RHQT Nb3Al block type dipole magnet

    SciTech Connect (OSTI)

    Yamada, R.; Ambrosio, G.; Barzi, E.; Kashikin, V.; Kikuchi, A.; Novitski, I.; Takeuchi, T.; Wake, M.; Zlobin, A.; /Fermilab /NIMC, Tsukuba /KEK, Tsukuba

    2005-09-01T23:59:59.000Z

    The design study of the block type 15-Tesla RHQT Nb{sub 3}Al dipole magnet, and its merits over Nb{sub 3}Sn magnets are presented. The copper stabilized RHQT Nb{sub 3}Al strand is now becoming commercially available for the application to the accelerator magnets. A 1 mm diameter RHQT Nb{sub 3}Al strand with filament size about 50 {mu}, non-copper Jc about 1000 A/mm{sup 2} at 15 Tesla at 4.2K, copper ratio of 50%, can now be produced over several hundred meters. The stress and strain characteristics of the Nb{sub 3}Al strand are superior to the Nb{sub 3}Sn strand. Another advantage is that it can tolerate a longitudinal strain up to 0.55%. The RHQT Nb{sub 3}Al Rutherford cable will have less chance of contamination of the stabilizer, compared to Nb{sub 3}Sn cable. These characteristics of the RHQT Nb{sub 3}Al will be beneficial for designing and producing 15-Tesla dipole magnets. An example 15-Tesla magnet cross section, utilizing the RHQT Nb{sub 3}Sn strand is presented. A systematic investigation on RHQT Nb{sub 3}Al strands, its Rutherford cables, and building a small racetrack magnet for cable testing are proposed.

  2. Measurement and Scaling Laws of the Sextupole Component in the LHC Dipole Magnets

    E-Print Network [OSTI]

    Walckiers, L; Bottura, L; Buzio, M; Dunkel, O; Fiscarelli, L; Montenero, G; Garcia Perez, J; Todesco, E

    2010-01-01T23:59:59.000Z

    One of the main requirements for the magnet operation of the Large Hadron Collider at CERN is the correction of the dynamic multipole errors produced. In particular, integrated sextupole errors in the main dipoles must be kept well below 0.1 units to ensure acceptable chromaticity. The feed-forward control of the LHC magnets is based on the Field Description for the LHC (FiDeL), a semi-empirical mathematical model capable of forecasting the magnet’s behaviours in order to suitably power the corrector scheme. Measurement campaign were recently undertaken to validate the model making use of a novel Fast rotating-coil Magnetic Measurement Equipment (FAME), able to detect superconductor decay and snapback transient with unprecedented accuracy and temporal resolution. We discuss in this paper the test setup and some measurement results confirming the FiDeL model.

  3. Interaction between a stationary electric charge and a stationary magnetic dipole

    E-Print Network [OSTI]

    W. B. Bonnor

    2002-03-13T23:59:59.000Z

    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.

  4. Discrete Symmetries on the Light Front and a General Relation Connecting Nucleon Electric Dipole and Anomalous Magnetic Moments

    E-Print Network [OSTI]

    Brodsky, S J; Hwang, D S

    2006-01-01T23:59:59.000Z

    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 ...

  5. HD1: Design and Fabrication of a 16 Tesla Nb3Sn DipoleMagnet

    SciTech Connect (OSTI)

    Hafalia, A.R.; Bartlett, S.E.; Capsi, S.; Chiesa, L.; Dietderich,D.R.; Ferracin, P.; Goli, M.; Gourlay, S.A.; Hannaford, C.R.; Highley,H.; Lietzke, A.F.; Liggins, N.; Mattafirri, S.; McInturff, A.D.; Nyman,M.; Sabbi, G.L.; Scanlan, R.M.; Swanson, J.

    2003-11-10T23:59:59.000Z

    The Lawrence Berkeley National Laboratory (LBNL) Superconducting Magnet Group has completed the design, fabrication and test of HD1, a 16 T block-coil dipole magnet. State of the art Nb{sub 3}Sn conductor was wound in double-layer racetrack coils and supported by an iron yoke and a tensioned aluminum shell. In order to prevent conductor movement under magnetic forces up to the design field, a coil pre-stress of 150 MPa was required. To achieve this level without damaging the brittle conductor, the target stress was generated during cool-down to 4.2 K by exploiting the thermal contraction differentials between yoke and shell. Accurate control of the shell tension during assembly was obtained using pressurized bladders and interference load keys. An integrated 3D CAD model was used to optimize magnetic and mechanical design and analysis.

  6. Performance analysis of HD1: a 16 Tesla Nb3Sn dipole Magnet

    SciTech Connect (OSTI)

    Mattafirri, S.; Bartlett, S.E.; Bish, P.A.; Caspi, S.; Dietderich, D.R.; Ferracin, P.; Gourlay, S.A.; Hannaford, C.R.; Hafalia, A.R.; Lau, W.G.; Lietzke, A.F.; McInturff, A.D.; Nyman, M.; Sabbi, G.L.; Scanlan, R.M.

    2005-06-01T23:59:59.000Z

    The Superconducting Magnet Group at Lawrence Berkeley National Laboratory (LBNL) has been developing technology for high field accelerator magnets from brittle conductors. HD1 is a single bore block dipole magnet using two, double-layer Nb{sub 3}Sn flat racetrack coils. The magnet was tested in October 2003 and reached a bore peak field of 16 T (94.5% of short sample). The average quench current plateau appeared to be limited by 'stick slip' conductor motions. Diagnostics recorded quench origins and preload distributions. Cumulative deformation of the mechanical structure has been observed. Quench velocity in different field regions has been measured and compared with model predictions. The results obtained during the HD1 test are presented and discussed.

  7. HD1: Design and Fabrication of a 16 Tesla Nb3Sn Dipole Magnet

    SciTech Connect (OSTI)

    Hafalia, A.R.; Barlett, S.E.; Caspi, S.; Chiesa, L.; Dietderich, D.R.; Ferracin, P.; Goli, M.; Gourlay, S.A.; Hannaford, C.R.; Higley, H.; Lietzke, A.F.; Liggins, N.; Mattafirri, S.; McInturff, A.D.; Myman, M.; Sabbi, G.L.; Scanlan, R.M.; Swanson, J.

    2003-10-01T23:59:59.000Z

    The Lawrence Berkeley National Laboratory (LBNL) Supcrconducting Magnet Group has completed the design, fabrication and tcst of HD1, a 16 T block-coil dipole magnet. State of the art Nb{sub 3}Sn conductor was wound in double-layer racetrack coils and supported by an iron yoke and a tensioned aluminum shell. In order to prevent conductor movement under magnetic forces up to the design field, a coil prestress of 150 MPa was required. To achieve this level without damaging the brittle conductor, the target stress was generated during cool-down to 4.2 K by exploiting the thermal contraction differentials between yoke and shell. Accurate control of the shell tension during assembly was obtained using pressurized bladders and interference load keys. An integrated 3D CAD model was used to optimize magnetic and mechanical design and analysis.

  8. A Coil Manufacturing Procedure for the ALICE Muon Arm Dipole Magnet

    E-Print Network [OSTI]

    Swoboda, D; CERN. Geneva

    1998-01-01T23:59:59.000Z

    A large Dipole Magnet is required for the Muon Arm spectrometer of the ALICE experiment[1,2]. The main parameters and basic design options of the dipole magnet have been described in [3]. The coils of the magnet will be wound from hollow Aluminium conductor of 50x50 mm˛ cross-section with a 30 mm diameter cooling hole in the centre. Different manufacturing techniques may be envisaged for the fabrication of the excitation coils. In this note we propose a procedure to construct the coils from straight extruded bars of half turn length. The different steps necessary to bend a half turn are described. A method to form complete turns, pancakes and the total coil is explained. A possible insulation process is presented. Advantages and critical areas of the coil construction process are highlighted in the conclusions. References [1]ALICE TP, CERN/LHCC 95-71 [2]ALICE TP Addendum, CERN/LHCC 96-32 [3]A Warm Magnet for the ALICE Muon Arm, ALICE 96/24, W.Flegel, D.Swoboda, CERN List of Figures Figure 1 Coil ...

  9. Design, Fabrication, and Test of a Superconducting Dipole Magnet Based on Tilted Solenoids

    SciTech Connect (OSTI)

    Caspi, S.; Dietderich, D. R.; Ferracin, P.; Finney, N. R.; Fuery, M. J.; Gourlay, S. A.; Hafalia, A. R.

    2007-06-01T23:59:59.000Z

    It can be shown that, by superposing two solenoid-like thin windings that are oppositely skewed (tilted) with respect to the bore axis, the combined current density on the surface is 'cos-theta' like and the resulting magnetic field in the bore is a pure dipole. As a proof of principle, such a magnet was designed, built and tested as part of a summer undergraduate intern project. The measured field in the 25mm bore, 4 single strand layers using NbTi superconductor, exceeded 1 T. The simplicity of this high field quality design, void of typical wedges end-spacers and coil assembly, is especially suitable for insert-coils using High Temperature Superconducting wire as well as for low cost superconducting accelerator magnets for High Energy Physics. Details of the design, construction and test are reported.

  10. Mechanical Behaviour of the Short Models of LHC Main Dipole Magnets

    E-Print Network [OSTI]

    Andreyev, N I; Casarejos, E; Kurtyka, T; Rathjen, C; Perini, D; Siegel, N; Tommasini, D; Vanenkov, I

    1998-01-01T23:59:59.000Z

    A series of single and twin aperture 1 metre magnet models has been built and tested in the framework of the R&D program of main superconducting dipole magnets for the Large Hadron Collider project. The se models, designed for a nominal field of 8.3 T at 1.8 K, have been constructed to test the performance of SC coils and to optimise various design options for the full length 15 metre long dipoles. T he models have been extensively equipped with a specially developed mechanical instrumentation, enabling both the control of main assembly parameters - like coil azimuthal and axial pre-load, stress i n the outer shrinking cylinder - and also the monitoring of magnet behaviour during cooling and energising, under the action of electromagnetic forces. The instrumentation used, mainly based on strain gauge transducers, is described and the results of mechanical measurements obtained during power tests of the models are discussed and compared with the design predictions based on Finite Element calc ulations.

  11. Limits on the neutrino magnetic dipole moment from the luminosity function of hot white dwarfs

    E-Print Network [OSTI]

    Marcelo Miguel Miller Bertolami

    2014-07-05T23:59:59.000Z

    Recent determinations of the white dwarf luminosity function (WDLF) from very large surveys have extended our knowledge of the WDLF to very high luminosities. This, together with the availability of new full evolutionary white dwarf models that are reliable at high luminosities, have opened the possibility of testing particle emission in the core of very hot white dwarfs, where neutrino processes are dominant. We use the available WDLFs from the Sloan Digital Sky Survey and the SuperCOSMOS Sky Survey to constrain the value of the neutrino magnetic dipole moment ($\\mu_\

  12. Determination of the magnetic dipole moment of the rho meson using 4 pion electroproduction data

    E-Print Network [OSTI]

    D. García Gudińo; G. Toledo Sánchez

    2015-02-20T23:59:59.000Z

    We determine the magnetic dipole moment of the rho meson using preliminary data from the BaBar Collaboration for the $e^+ e^- \\to \\pi^+ \\pi^- 2 \\pi^0$ process, in the center of mass energy range from 0.9 to 2.2 GeV. We describe the $\\gamma^* \\to 4\\pi$ vertex using a vector meson dominance model, including the intermediate resonance contributions relevant at these energies. We find that $\\mu_\\rho = 2.1 \\pm 0.5$ in $e/2 m_\\rho$ units.

  13. Proposal for the Award of a Contract for the Supply, Installation and Commissioning of Three Hydraulic Presses for the Assembly and Welding of the LHC Superconducting Dipole Magnets

    E-Print Network [OSTI]

    1998-01-01T23:59:59.000Z

    Proposal for the Award of a Contract for the Supply, Installation and Commissioning of Three Hydraulic Presses for the Assembly and Welding of the LHC Superconducting Dipole Magnets

  14. Proposal for the Award of a Contract for the Supply, Installation and Commissioning of a Hydraulic Press for Collaring the LHC Superconducting Dipole Magnets

    E-Print Network [OSTI]

    1996-01-01T23:59:59.000Z

    Proposal for the Award of a Contract for the Supply, Installation and Commissioning of a Hydraulic Press for Collaring the LHC Superconducting Dipole Magnets

  15. Test Results for HD1, a 16 Tesla Nb3Sn Dipole Magnet

    SciTech Connect (OSTI)

    Lietzke, A.F.; Bartlett, S.; Bish, P.; Caspi, S.; Chiesa, L.; Dietderich, D.; Ferracin, P.; Gourlay, S.A.; Goli, M.; Hafalia, R.R.; Higley, H.; Hannaford, R.; Lau, W.; Liggens, N.; Mattafirri, S.; McInturff, A.; Nyman, M.; Sabbi, G.; Scanlan, R.; Swanson, J.

    2003-10-01T23:59:59.000Z

    The Superconducting Magnet Group at Lawrence Berkeley National Laboratory has been developing the technology for using brittle superconductor in high-field accelerator magnets. HD1, the latest in a series of magnets, contains two, double-layer Nb{sub 3}Sn flat racetrack coils. This single-bore dipole configuration, using the highest performance conductor available, was designed and assembled for a 16 tesla conductor/structure/pre-stress proof-of-principle. With the combination of brittle conductor and high Lorentz stress, considerable care was taken to predict the magnet's mechanical responses to pre-stress, cool-down, and excitation. Subsequent cold testing satisfied expectations: Training started at 13.6 T, 83% of 'short-sample', achieved 90% in 10 quenches, and reached its peak bore field (16 T) after 19 quenches. The average plateau, {approx}92% of 'short-sample', appeared to be limited by 'stick-slip' conductor motions, consistent with the 16.2 T conductor 'lift-off' pre-stress that was chosen for this first test. Some lessons learned and some implications for future conductor and magnet technology development are presented and discussed.

  16. Recent Test Results of the High Field Nb3Sn Dipole Magnet HD2

    SciTech Connect (OSTI)

    Ferracin, P.; Bingham, B.; Caspi, S.; Cheng, D. W.; Dietderich, D. R.; Felice, H.; Hafalia, A. R.; Hannaford, C. R.; Joseph, J.; Lietzke, A. F.; Lizarazo, J.; Sabbi, G.; Wang, X.

    2009-10-19T23:59:59.000Z

    The 1 m long Nb{sub 3}Sn dipole magnet HD2, fabricated and tested at Lawrence Berkeley National Laboratory, represents a step towards the development of block-type accelerator quality magnets operating in the range of 13-15 T. The magnet design features two coil modules composed of two layers wound around a titanium-alloy pole. The layer 1 pole includes a round cutout to provide room for a bore tube with a clear aperture of 36 mm. After a first series of tests where HD2 reached a maximum bore field of 13.8 T, corresponding to an estimated peak field on the conductor of 14.5 T, the magnet was disassembled and reloaded without the bore tube and with a clear aperture increased to 43 mm. We describe in this paper the magnet training observed in two consecutive tests after the removal of the bore tube, with a comparison of the quench performance with respect to the previous tests. An analysis of the voltage signals recorded before and after training quenches is then presented and discussed, and the results of coil visual inspections reported.

  17. RHIC spin flipper AC dipole controller

    SciTech Connect (OSTI)

    Oddo, P.; Bai, M.; Dawson, C.; Gassner, D.; Harvey, M.; Hayes, T.; Mernick, K.; Minty, M.; Roser, T.; Severino, F.; Smith, K.

    2011-03-28T23:59:59.000Z

    The RHIC Spin Flipper's five high-Q AC dipoles which are driven by a swept frequency waveform require precise control of phase and amplitude during the sweep. This control is achieved using FPGA based feedback controllers. Multiple feedback loops are used to and dynamically tune the magnets. The current implementation and results will be presented. Work on a new spin flipper for RHIC (Relativistic Heavy Ion Collider) incorporating multiple dynamically tuned high-Q AC-dipoles has been developed for RHIC spin-physics experiments. A spin flipper is needed to cancel systematic errors by reversing the spin direction of the two colliding beams multiple times during a store. The spin flipper system consists of four DC-dipole magnets (spin rotators) and five AC-dipole magnets. Multiple AC-dipoles are needed to localize the driven coherent betatron oscillation inside the spin flipper. Operationally the AC-dipoles form two swept frequency bumps that minimize the effect of the AC-dipole dipoles outside of the spin flipper. Both AC bumps operate at the same frequency, but are phase shifted from each other. The AC-dipoles therefore require precise control over amplitude and phase making the implementation of the AC-dipole controller the central challenge.

  18. Torsional Oscillations of Relativistic Stars with Dipole Magnetic Fields II. Global Alfvén Modes

    E-Print Network [OSTI]

    H. Sotani; K. D. Kokkotas; N. Stergioulas; M. Vavoulidis

    2006-11-21T23:59:59.000Z

    We investigate torsional Alfv\\'{e}n modes of relativistic stars with a global dipole magnetic field. It has been noted recently (Glampedakis et al. 2006) that such oscillation modes could serve as as an alternative explanation (in contrast to torsional crustal modes) for the SGR phenomenon, if the magnetic field is not confined to the crust. We compute global Alfv\\'{e}n modes for a representative sample of equations of state and magnetar masses, in the ideal MHD approximation and ignoring $\\ell \\pm 2$ terms in the eigenfunction. We find that the presence of a realistic crust has a negligible effect on Alfv\\'{e}n modes for $B > 4\\times 10^{15}$ G. Furthermore, we find strong avoided crossings between torsional Alfv\\'{e}n modes and torsional crust modes. For magnetar-like magnetic field strengths, the spacing between consecutive Alfv\\'{e}n modes is of the same order as the gap of avoided crossings. As a result, it is not possible to identify modes of predominantly crustal character and all oscillations are predominantly Alfv\\'{e}n-like. Interestingly, we find excellent agreement between our computed frequencies and observed frequencies in two SGRs, for a maximum magnetic field strenght in the range of (0.8--1.2)$\\times 10^{16}$ G.

  19. Harmonic Analysis Errors in Calculating Dipole,

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

    to reduce the harmonic field calculation errors. A conformal transfor- mation of a multipole magnet into a dipole reduces these errors. Dipole Magnet Calculations A triangular...

  20. Correction of Magnetization Sextupole in One-Meter Long Dipole Magnets Using Passing Superconductor

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    Fermilab Passive SuperconductorTest at the ICFA Workshop,Maydipole magnet. The superconductorin the passivecorrectorcanmagnetizationof the superconductingcable in the test

  1. Novel Approach to Linear Accelerator Superconducting Magnet System

    SciTech Connect (OSTI)

    Kashikhin, Vladimir; /Fermilab

    2011-11-28T23:59:59.000Z

    Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

  2. Passive magnetic bearing system

    DOE Patents [OSTI]

    Post, Richard F.

    2014-09-02T23:59:59.000Z

    An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.

  3. Mechanical Design of HD2, a 15 T Nb3Sn Dipole Magnet with a 35 mm Bore

    SciTech Connect (OSTI)

    Ferracin, P.; Bartlett, S.E.; Caspi, S.; Dietderich, D.R.; Gourlay, S.A.; Hafalia, A.R.; Hannaford, C.R.; Lietzke, A.F.; Mattafirri, S.; McInturff, A.D.; Sabbi, G.L.

    2006-06-01T23:59:59.000Z

    After the fabrication and test of HD1, a 16 T Nb{sub 3}Sn dipole magnet based on flat racetrack coil configuration, the Superconducting Magnet Program at Lawrence Berkeley National Laboratory (LBNL) is developing the Nb{sub 3}Sn dipole HD2. With a dipole field above 15 T, a 35 mm clear bore, and nominal field harmonics within a fraction of one unit, HD2 represents a further step towards the application of block-type coils to high-field accelerator magnets. The design features tilted racetrack-type ends, to avoid obstructing the beam path, and a 4 mm thick stainless steel tube, to support the coil during the preloading operation. The mechanical structure, similar to the one used for HD1, is based on an external aluminum shell pretensioned with pressurized bladders. Axial rods and stainless steel plates provide longitudinal support to the coil ends during magnet excitation. A 3D finite element analysis has been performed to evaluate stresses and deformations from assembly to excitation, with particular emphasis on conductor displacements due to Lorentz forces. Numerical results are presented and discussed.

  4. Accelerator Quality HTS Dipole Magnet Demonstrator Designs for the EuCARD-2, 5 Tesla 40 mm Clear Aperture Magnet

    E-Print Network [OSTI]

    Kirby, GA; Ballarino, A; Bottura, L; Chouika, N; Clement, S; Datskov, V; Fajardo, L; Fleiter, J; Gauthier, R; Gentini, L; Lambert, L; Lopes, M; Perez, JC; de Rijk, G; Rijllart, A; Rossi, L; ten Kate, H; Durante, M; Fazilleau, P; Lorin, C; Härö, E; Stenvall, A; Caspi, S; Marchevsky, M; Goldacker, W; Kario, A

    2015-01-01T23:59:59.000Z

    Future high-energy accelerators will need very high magnetic fields in the range of 20 T. The EuCARD-2 work-package-10 is a collaborative push to take HTS materials into an accelerator quality demonstrator magnet. The demonstrator will produce 5 T standalone and between 17 T and 20 T, when inserted into the 100 mm aperture of Fresca-2 high field out-sert magnet. The HTS magnet will demonstrate the field strength and field quality that can be achieved. An effective quench detection and protection system will have to be developed to operate with the HTS superconducting materials. This paper presents a ReBCO magnet design using multi strand Roebel cable that develops a stand-alone field of 5 T in a 40 mm clear aperture and discusses the challenges associated with good field quality using this type of material. A selection of magnet designs is presented as result of a first phase of development.

  5. Accelerator Quality HTS Dipole Magnet Demonstrator designs for the EuCARD-2, 5 Tesla 40 mm Clear Aperture Magnet

    E-Print Network [OSTI]

    Kirby, G; Ballarino, A; Bottura, L; Chouika, N; Clement, S; Datskov, V; Fajardo, L; Fleiter, J; Gauthier, R; Lambert, L; Lopes, M; Perez, J; DeRijk, G; Rijllart, A; Rossi, L; Ten Kate, H; Durante, M; Fazilleau, P; Lorin, C; Haro, E; Stenvall, A; Caspi, S; Marchevsky, M; Goldacker, W; Kario, A

    2014-01-01T23:59:59.000Z

    Future high-energy accelerators will need very high magnetic fields in the range of 20 T. The EuCARD-2 work-package-10 is a collaborative push to take HTS materials into an accelerator quality demonstrator magnet. The demonstrator will produce 5 T standalone and between 17 T and 20 T, when inserted into the 100 mm aperture of Fresca-2 high field out-sert magnet. The HTS magnet will demonstrate the field strength and field quality that can be achieved. An effective quench detection and protection system will have to be developed to operate with the HTS superconducting materials. This paper presents a ReBCO magnet design using multi strand Roebel cable that develops a stand-alone field of 5 T in a 40 mm clear aperture and discusses the challenges associated with good field quality using this type of material. A selection of magnet designs is presented as result of a first phase of development.

  6. Giant Skyrmions Stabilized by Dipole-Dipole Interactions in Thin Ferromagnetic Films

    E-Print Network [OSTI]

    Ezawa, Motohiko

    2011-01-01T23:59:59.000Z

    Motivated by a recent magnetization reversal experiment on a TbFeCo thin film, we study a topological excitation in the anisotropic nonlinear sigma model together with the Zeeman and magnetic dipole-dipole interactions. Dipole-dipole interactions turn a ferromagnet into a frustrated spin system, which allows a nontrivial spin texture such as a giant skyrmion. We derive an analytic formula for the skyrmion radius. The radius is controllable by the external magnetic field. It is intriguing that a skyrmion may have already been observed as a magnetic domain. A salient feature is that a single skyrmion can be created or destroyed experimentally. An analysis is made also on skyrmions in chiral magnets.

  7. Giant Skyrmions Stabilized by Dipole-Dipole Interactions in Thin Ferromagnetic Films

    SciTech Connect (OSTI)

    Ezawa, Motohiko [Department of Applied Physics, University of Tokyo, Hongo 7-3-1, 113-8656 (Japan)

    2010-11-05T23:59:59.000Z

    Motivated by a recent magnetization reversal experiment on a TbFeCo thin film, we study a topological excitation in the anisotropic nonlinear sigma model together with the Zeeman and magnetic dipole-dipole interactions. Dipole-dipole interactions turn a ferromagnet into a frustrated spin system, which allows a nontrivial spin texture such as a giant Skyrmion. We derive an analytic formula for the Skyrmion radius. The radius is controllable by the external magnetic field. It is intriguing that a Skyrmion may have already been observed as a magnetic domain. A salient feature is that a single Skyrmion can be created or destroyed experimentally. An analysis is made also on Skyrmions in chiral magnets.

  8. Giant Skyrmions Stabilized by Dipole-Dipole Interactions in Thin Ferromagnetic Films

    E-Print Network [OSTI]

    Motohiko Ezawa

    2010-11-03T23:59:59.000Z

    Motivated by a recent magnetization reversal experiment on a TbFeCo thin film, we study a topological excitation in the anisotropic nonlinear sigma model together with the Zeeman and magnetic dipole-dipole interactions. Dipole-dipole interactions turn a ferromagnet into a frustrated spin system, which allows a nontrivial spin texture such as a giant skyrmion. We derive an analytic formula for the skyrmion radius. The radius is controllable by the external magnetic field. It is intriguing that a skyrmion may have already been observed as a magnetic domain. A salient feature is that a single skyrmion can be created or destroyed experimentally. An analysis is made also on skyrmions in chiral magnets.

  9. Modular tokamak magnetic system

    DOE Patents [OSTI]

    Yang, Tien-Fang (Wayland, MA)

    1988-01-01T23:59:59.000Z

    A modular tokamak system comprised of a plurality of interlocking moldules. Each module is comprised of a vacuum vessel section, a toroidal field coil, moldular saddle coils which generate a poloidal magnetic field and ohmic heating coils.

  10. Artificial light and quantum order in systems of screened dipoles Xiao-Gang Wen

    E-Print Network [OSTI]

    Wen, Xiao-Gang

    Artificial light and quantum order in systems of screened dipoles Xiao-Gang Wen Department discussed. The existence of artificial light (as well as artificial electron) in condensed matter systems a new kind of order - quantum order. To test this idea in experiments, we study systems of screened

  11. Assembly and Test of HD2, a 36 mm bore high field Nb3Sn Dipole Magnet

    SciTech Connect (OSTI)

    Ferracin, P.; Bingham, B.; Caspi, S.; Cheng, D. W,.; Dietderich, D. R.; Felice, H.; Godeke, A.; Hafalia, A. R.; Hannaford, C. R.; Joseph, J.; Lietzke, A. F.; Lizarazo, J.; Sabbi, G.; Trillaud, F.; Wang, X.

    2008-08-17T23:59:59.000Z

    We report on the fabrication, assembly, and test of the Nb{sub 3}Sn dipole magnet HD2. The magnet, aimed at demonstrating the application of Nb{sub 3}Sn superconductor in high field accelerator-type dipoles, features a 36 mm clear bore surrounded by block-type coils with tilted ends. The coil design is optimized to minimize geometric harmonics in the aperture and the magnetic peak field on the conductor in the coil ends. The target bore field of 15 T at 4.3 K is consistent with critical current measurements of extracted strands. The coils are horizontally pre-stressed during assembly using an external aluminum shell pre-tensioned with water-pressurized bladders. Axial pre-loading of the coil ends is accomplished through two end plates and four aluminum tension rods. The strain in coil, shell, and rods is monitored with strain gauges during assembly, cool-down and magnet excitation, and compared with 3D finite element computations. Magnet's training performance, quench locations, and ramp-rate dependence are then analyzed and discussed.

  12. Magnetic System for the CLAS12 Proposal

    SciTech Connect (OSTI)

    Statera, Marco [INFN, Ferrara (Italy); Contalbrigo, Marco M. [INFN, Ferrara (Italy); Pappalardo, Luciano Libero [INFN, Ferrara (Italy); Barion, Luca [INFN, Ferrara (Italy); Bertelli, S. [INFN, Ferrara (Italy); Ciullo, Giuseppe [INFN, Ferrara (Italy); Lenisa, Paolo [INFN, Ferrara (Italy)

    2013-06-01T23:59:59.000Z

    The conceptual design of a magnetic system for an experiment to measure the transverse spin effects in semi-inclusive Deep Inelastic Scattering (SIDIS) at 11 GeV with a transversely polarized target using the CLAS12 detector at Jefferson Lab is presented. A proposal has been submitted to study spin azimuthal asymmetries in SIDIS using an 11-GeV polarized electron beam from the upgraded CEBAF facility and the CLAS12 detector equipped with a transversely polarized target. The main focus of the experiment will be the measurement of transverse target single and double spin asymmetries in the reaction ep{up_arrow} -> ehX, where e is an electron, p{up_arrow} is transversely polarized proton, h is a meson (e.g., a pion or a kaon) and X is the undetected final state. The details of the conceptual design of the shielding magnetic system and transverse dipole are reported.

  13. Density profiles of plasmas confined by the field of a Levitating Dipole Magnet

    E-Print Network [OSTI]

    Boxer, Alexander C

    2009-01-01T23:59:59.000Z

    A 4-channel microwave interferometer (center frequency: 60 GHz) has been constructed to measure the density profiles of plasmas confined within the Levitated Dipole Experiment (LDX). LDX is the first and only experiment ...

  14. Magnetic Field Measurement System

    SciTech Connect (OSTI)

    Kulesza, Joe; Johnson, Eric; Lyndaker, Aaron; Deyhim, Alex; Waterman, Dave; Blomqvist, K. Ingvar [Advanced Design Consulting USA, 126 Ridge Road, P.O. Box 187, Lansing, NY 14882 (United States); Dunn, Jonathan Hunter [MAX-lab, SE-221 00 Lund (Sweden)

    2007-01-19T23:59:59.000Z

    A magnetic field measurement system was designed, built and installed at MAX Lab, Sweden for the purpose of characterizing the magnetic field produced by Insertion Devices (see Figure 1). The measurement system consists of a large granite beam roughly 2 feet square and 14 feet long that has been polished beyond laboratory grade for flatness and straightness. The granite precision coupled with the design of the carriage yielded minimum position deviations as measured at the probe tip. The Hall probe data collection and compensation technique allows exceptional resolution and range while taking data on the fly to programmable sample spacing. Additional flip coil provides field integral data.

  15. Improved determination of Heavy Quarkonium magnetic dipole transitions in pNRQCD

    E-Print Network [OSTI]

    Antonio Pineda; J. Segovia

    2014-11-24T23:59:59.000Z

    We compute the magnetic dipole transitions between low lying Heavy Quarkonium states in a model independent way. We use the weak-coupling version of the effective field theory named potential NRQCD with the static potential exactly incorporated in the leading order Hamiltonian. The precision we reach is $k_{\\gamma}^3/m^2\\times{\\cal O}(\\alpha_s^2,v^2)$ and $k_{\\gamma}^3/m^2\\times{\\cal O}(v^4)$ for the allowed and forbidden transitions respectively. We also resum the large logarithms associated to the heavy quark mass scale. The specific transitions considered in this paper are the following: $\\Upsilon(1S) \\to \\eta_b(1S)\\,\\gamma$, $J/\\psi(1S) \\to \\eta_c(1S)\\,\\gamma$, $h_b(1P) \\to \\chi_{b0,1}(1P)\\,\\gamma$, $\\chi_{b2}(1P) \\to h_b(1P)\\,\\gamma$, $\\Upsilon(2S) \\to \\eta_b(2S)\\,\\gamma$, $\\Upsilon(2S) \\to \\eta_b(1S)\\,\\gamma$ and $\\eta_b(2S)\\to\\Upsilon(1S)\\,\\gamma$. The effect of the new power counting is found to be large and the exact treatment of the soft logarithms of the static potential makes the factorization scale dependence much smaller. The convergence for the $b\\bar b$ ground state is quite good, and also quite reasonable for the $c\\bar c$ ground state and the $b\\bar b$ 1P state. For all of them we give solid predictions. For the 2S decays the situation is less conclusive, yet our results are perfectly consistent with existing data, as the previous disagreement with experiment for the $\\Upsilon(2S) \\to \\eta_b(1S)\\,\\gamma$ decay fades away. We also profit to compute some expectation values like the electromagnetic radius, r^2, or p^2. We find r^2 to be nicely convergent in all cases, whereas the convergence of p^2 is typically worse.

  16. Passive Superconductor: A Viable Method of Controlling Magnetization Multipoles in the SSC Dipole

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    335. M. N. Wilson, Superconductjng Magnets, Clarendon OxfordNiobium-Titanium Superconductors, University of Wisconsin,Residual Fields in Superconducting Magnets", published in

  17. Use of an elliptical aperture to control saturation in closely-coupled, cold iron, superconducting dipole magnets

    SciTech Connect (OSTI)

    Morgan, G.

    1985-01-01T23:59:59.000Z

    The high fields permitted by superconducting windings result in saturation of closely-coupled iron in dipole and quadrupole beam transport magnets. Coupland suggested using a triangular cutout at the poles to reduce the change in the sextupole (b/sub 2/) term due to saturation. The use of an elliptical aperture in a close-coupled dipole for the Relativistic Heavy Ion Collider (RHIC) has been studied using the BNL computer program MDP (a version of GFUN). The ellipse aspect ratio was varied while holding the horizontal (minor) radius constant. The proper aspect ratio gives no shift in b/sub 2/ sue to saturation, and a reduction in the b/sub 4/ shift. A modification of the ellipse also reduces b/sub 4/. The elliptical aperture introduces a large b/sub 2/ term at low field which must be compensated for by the coil design. A practical coil design which does this for the RHIC magnet is presented. 5 refs., 2 figs., 3 tabs.

  18. ac dipole system: Topics by E-print Network

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

    a considerable amount of information is availableon Wu, Shin-Tson 84 A nonlinear robust HVDC control for a parallel ACDC power system Engineering Websites Summary: A nonlinear...

  19. Levitation Control System in the Levitated Dipole Experiment

    E-Print Network [OSTI]

    . A phase locked loop (PLL) will produce an output from a voltage controlled oscillator (VCO) phase locked Oscillations in the system will occur with a frequency on the order of 1 Hertz #12;Levitated Cheerio Experiment coils will be used to damp oscillations in the other degrees of freedom. #12;Position Detection System

  20. Short cycle pulse sequence for dynamical decoupling of local fields and dipole-dipole interactions

    E-Print Network [OSTI]

    S. A. Moiseev; V. A. Skrebnev

    2014-12-11T23:59:59.000Z

    We propose a new pulse sequence for dynamical averaging of the dipole-dipole interactions and inhomogeneities of the magnetic fields in the nuclear spin system. The sequence contains a short cycle of the periodic resonant pulse excitation that offers new possibilities for implementing the long-lived multi-qubit quantum memory on the condensed spin ensembles that are so important for construction of universal quantum computer and long-distance quantum communications.

  1. Design calculations and measurements of a dipole magnet with Permendur pole pieces

    SciTech Connect (OSTI)

    Early, R.A.; Cobb, J.K.; Oijala, J.E.

    1989-03-01T23:59:59.000Z

    A redesign of the SLC South Linac-to-Ring beam line required that the width of a good field of three of the bending magnets be increased while utilizing the same yoke and coils. Further requirements were that the resulting magnets should have the same strength at two different operating currents as the original magnets. The idea of replacing the steel poles with pole pieces of the high permeability material Permendur was investigated. Design calculations were done using TOSCA and POISSON. An existing prototype magnet was modified with Permendur poles, and magnetic measurements were done. The new magnets were completed, and measurements agreed well with the calculations. 4 refs., 14 figs.

  2. Abstract--The Levitated Dipole Experiment (LDX) is a new, innovative magnetic confinement fusion experiment

    E-Print Network [OSTI]

    Garnier, Darren T.

    ranging from vacuum to normal pressure. The magnet is wound on a stainless steel form. The heat exchanger is used also to warm up the magnet to 18-20 K during coil electrical discharging

  3. Improvement of microwave feeding on a large bore ECRIS with permanent magnets by using coaxial semi-dipole antenna

    SciTech Connect (OSTI)

    Kurisu, Yosuke; Sakamoto, Naoki; Kiriyama, Ryutaro; Takenaka, Tomoya; Nozaki, Dai; Yano, Keisuke; Sato, Fuminobu; Kato, Yushi; Iida, Toshiyuki [Division of Electrical, Electronic and Information Engineering, Graduate School of Engineering, Osaka Univ. 2-1 Yamadaoka, Suita, Osaka, 565-0871 (Japan)

    2012-11-06T23:59:59.000Z

    We are constructing a tandem type electron cyclotron resonance (ECR) ion source (ECRIS). The first stage of this ECRIS has a large-bore with cylindrically comb-shaped permanent magnets. 2.45GHz and 11-13GHz microwaves can be supplied individually and simultaneously to the plasma chamber. For 2.45GHz, a coaxial semi-dipole antenna is used to feed the microwaves. In previous experiments, there were two problems encountered when running the 2.45GHz microwaves. High incident power was necessary to keep ECR discharge at low operating pressure because of high reflected microwave power. The surface of a support insulator between the inner and the outer electrodes of coaxial semi-dipole antenna was easily metalized by sputtering of the metal wall inside the chamber. The purpose of this study was to solve these problems. Performing several simulation experiments supports the hypothesis that the position of the support insulator is significant for microwave power efficiency. The end result was the ability to sustain ECR discharges at extremely low incident microwave power, several tens of watts, by optimized matching of the position and shape of the insulator.

  4. Fabrication and Test Results of a Prototype, Nb3Sn Superconducting Racetrack Dipole Magnet

    SciTech Connect (OSTI)

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

    1998-09-01T23:59:59.000Z

    A prototype, Nb{sub 3}Sn superconducting magnet, utilizing a racetrack coil design has been built and tested. This magnet represents the first step in a recently implemented program to develop a high field, accelerator quality magnet. This magnet was constructed with coils wound from conductor developed for the ITER project, limiting the magnet to a field of 6-7 Tesla. Subsequent magnets in the program will utilize improved conductor, culminating in a magnet design capable of producing fields approaching 15 Tesla. The simple geometry is more suitable for the use of brittle superconductors necessary to eventually reach high field levels. In addition, fewer and simpler parts are used in fabricating these coils compared with the more conventional cosine theta cross section coils. The general fabrication steps, mechanical design and quench performance are discussed.

  5. Magnetic refrigeration for spacecraft systems

    SciTech Connect (OSTI)

    Barclay, J.A.

    1981-01-01T23:59:59.000Z

    Magnetic refrigerators, i.e., those that use the magnetocaloric effect of a magnetic working material in a thermodynamic cycle, offer potentially reliable, and efficient refrigeration over a variety of temperature ranges and cooling powers. A descriptive analysis of magnetic refrigeration systems is performed with particular emphasis on more efficient infrared detector cooling. Three types of magnetic refrigerator designs are introduced to illustrate some of the possibilities.

  6. Scales in the fine structure of the magnetic dipole resonance: A wavelet approach to the shell model

    SciTech Connect (OSTI)

    Petermann, I.; Langanke, K. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Martinez-Pinedo, G. [GSI Helmholtzzentrum fuer Schwerionenforschung, D-64291 Darmstadt (Germany); Neumann-Cosel, P. von [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); Nowacki, F. [Institute Pluridisciplinaire Hubert Curien, F-67037 Strasbourg (France); Richter, A. [Institut fuer Kernphysik, Technische Universitaet Darmstadt, D-64289 Darmstadt (Germany); ECT, Villa Tambosi, I-38050 Villazano, Trento (Italy)

    2010-01-15T23:59:59.000Z

    Wavelet analysis is applied as a tool for the examination of magnetic dipole (M1) strength distributions in pf-shell nuclei by the extraction of wavelet scales. Results from the analysis of theoretical M1 strength distributions calculated with the KB3G interaction are compared to experimental data from (e,e{sup '}) experiments and good agreement of the deduced wavelet scales is observed. This provides further insight into the nature of the scales from the model results. The influence of the number of Lanczos iterations on the development and stability of scales and the role of the model space in terms of the truncation level are studied. Moreover, differences in the scales of spin and orbital parts of the M1 strength are investigated, as is the use of different effective interactions (KB3G, GXPF1, and FPD6).

  7. Magnetic-dipole transitions in highly-charged ions as a basis of ultra-precise optical clocks

    E-Print Network [OSTI]

    V. I. Yudin; A. V. Taichenachev; A. Derevianko

    2014-11-01T23:59:59.000Z

    We evaluate the feasibility of using magnetic-dipole (M1) transitions in highly-charged ions as a basis of an optical atomic clockwork of exceptional accuracy. We consider a range of possibilities, including M1 transitions between clock levels of the same fine-structure and hyperfine-structure manifolds. In highly charged ions these transitions lie in the optical part of the spectra and can be probed with lasers. The most direct advantage of our proposal comes from the low degeneracy of clock levels and the simplicity of atomic structure in combination with negligible quadrupolar shift. We demonstrate that such clocks can have projected fractional accuracies below the $10^{-20}-10^{-21}$ level for all common systematic effects, such as black-body radiation, Zeeman, AC-Stark and quadrupolar shifts. Notice that usually-employed hyperfine clock transitions lie in the microwave spectral region. Our proposal moves such transitions to the optical domain. As the hyperfine transition frequencies depend on the fine-structure constant, electron-to-proton mass ratio, and nuclear magnetic moment, our proposal expands the range of experimental schemes for probing space and time variations of fundamental constants.

  8. A Superconducting Bending Magnet System for a Compact Synchrotron Light Source

    E-Print Network [OSTI]

    Green, M.A.

    2011-01-01T23:59:59.000Z

    Garren, "Optimization of Superconducting Bending Magnets foral, "Development of a Superconducting Compact Storage Ringsdesigns M. A Green, "Superconducting Dipole Magnets for

  9. Long-wavelength anomalous diffusion mode in the two-dimensional XY dipole magnet

    E-Print Network [OSTI]

    Abanov, Artem; Kashuba, A.; Pokrovsky, Valery L.

    1997-01-01T23:59:59.000Z

    e , ETH-H dynamics diffusio PHYSICAL REVIEW B 1 AUGUST 1997-IIVOLUME 56, NUMBER 6 energy v . Each kind of excitations has its specific dispersion relation or spectrum v5e(p). A wide scope of physical problems can be solved assuming... magnetization field S(x), Hdip5 g 2(k ~ Skk !~S2kk! uku . ~4! 3182 56AR. ABANOV, A. KASHUBA, AND V. L. POKROVSKY r in small spin fluctuations f . We take the uniform magnetic d quantities are defined by f E 2 nonquadrati ~ k 2 , appears...

  10. Magnetic dipole discharges. II. Cathode and anode spot discharges and probe diagnostics

    SciTech Connect (OSTI)

    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)

    2013-08-15T23:59:59.000Z

    The high current regime of a magnetron-type discharge has been investigated. The discharge uses a permanent magnet as a cold cathode which emits secondary electrons while the chamber wall or a grounded electrode serves as the anode. As the discharge voltage is increased, the magnet develops cathode spots, which are short duration arcs that provide copious electrons to increase the discharge current dramatically. Short (1 ?s), high current (200 A) and high voltage (750 V) discharge pulses are produced in a relaxation instability between the plasma and a charging capacitor. Spots are also observed on a negatively biased plane Langmuir probe. The probe current pulses are as large as those on the magnet, implying that the high discharge current does not depend on the cathode surface area but on the properties of the spots. The fast current pulses produce large inductive voltages, which can reverse the electrical polarity of the magnet and temporarily operate it as an anode. The discharge current may also oscillate at the frequency determined by the charging capacitor and the discharge circuit inductance. Each half cycle of high-current current pulses exhibits a fast (?10 ns) current rise when a spot is formed. It induces high frequency (10–100 MHz) transients and ringing oscillations in probes and current circuits. Most probes behave like unmatched antennas for the electromagnetic pulses of spot discharges. Examples are shown to distinguish the source of oscillations and some rf characteristics of Langmuir probes.

  11. EIGHT-TESLA SYNCHROTRON DIPOLES -- DESIGN ALTERNATIVES

    E-Print Network [OSTI]

    Gilbert, W.S.

    2011-01-01T23:59:59.000Z

    14, 1979 LBL -8410 EIGHT-TESLA SYNCHROTRON DIPOLES -- DESIGNprivately owned rights. EIGHT-TESLA SYNCHROTRON DIPOLES --bending magnets in the 4 to 5 tesla field range have been,

  12. Detection of magnetic dipole lines of Fe XII in the ultraviolet spectrum of the dwarf star Epsilon Eri

    E-Print Network [OSTI]

    C. Jordan; A. D. McMurry; S. A. Sim; M. Arulvel

    2001-01-17T23:59:59.000Z

    We report observations of the dwarf star Epsilon Eri (K2 V) made with the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST). The high sensitivity of the STIS instrument has allowed us to detect the magnetic dipole transitions of Fe XII at 1242.00A and 1349.38A for the first time in a star other than the Sun. The width of the stronger line at 1242.00A has also been measured; such measurements are not possible for the permitted lines of Fe XII in the extreme ultraviolet. To within the accurcy of the measurements, the N V and the Fe XII lines occur at their rest wavelengths. Electron densities and line widths have been measured from other transition region lines. Together, these can be used to investigate the non-thermal energy flux in the lower and upper transition region, which is useful in constraining possible heating processes. The Fe XII lines are also present in archival STIS spectra of other G/K-type dwarfs.

  13. Actuation of Micro-Optomechanical Systems Via Cavity-Enhanced Optical Dipole Forces

    E-Print Network [OSTI]

    Matt Eichenfield; Christopher P. Michael; Raviv Perahia; Oskar Painter

    2007-04-30T23:59:59.000Z

    We demonstrate a new type of optomechanical system employing a movable, micron-scale waveguide evanescently-coupled to a high-Q optical microresonator. Micron-scale displacements of the waveguide are observed for milliwatt(mW)-level optical input powers. Measurement of the spatial variation of the force on the waveguide indicates that it arises from a cavity-enhanced optical dipole force due to the stored optical field of the resonator. This force is used to realize an all-optical tunable filter operating with sub-mW control power. A theoretical model of the system shows the maximum achievable force to be independent of the intrinsic Q of the optical resonator and to scale inversely with the cavity mode volume, suggesting that such forces may become even more effective as devices approach the nanoscale.

  14. Magnetically coupled system for mixing

    SciTech Connect (OSTI)

    Miller, III, Harlan; Meichel, George; Legere, Edward; Malkiel, Edwin; Woods, Robert Paul; Ashley, Oliver; Katz, Joseph; Ward, Jason; Petersen, Paul

    2014-04-01T23:59:59.000Z

    The invention provides a mixing system comprising a magnetically coupled drive system and a foil for cultivating algae, or cyanobacteria, in an open or enclosed vessel. The invention provides effective mixing, low energy usage, low capital expenditure, and ease of drive system component maintenance while maintaining the integrity of a sealed mixing vessel.

  15. Infinite Geometric Frustration in a Cubic Dipole Cluster

    E-Print Network [OSTI]

    Johannes Schönke; Tobias M. Schneider; Ingo Rehberg

    2014-08-18T23:59:59.000Z

    The geometric arrangement of interacting (magnetic) dipoles is a question of fundamental importance in physics, chemistry and engineering. Motivated by recent progress concerning the self-assembly of magnetic structures, the equilibrium orientation of 8 interacting dipoles in a cubic cluster is investigated in detail. Instead of discrete equilibria we find a new type of ground state consisting of infinitely many orientations. This continuum of energetically degenerate states represents a yet unknown form of magnetic frustration. The corresponding dipole rotations in the flat potential valley of this Goldstone mode enable the construction of frictionless magnetic couplings. Using novel computer-assisted algebraic geometry methods, we moreover completely enumerate all equilibrium configurations. The seemingly simple cubic system allows for exactly 9536 unstable discrete equilibria falling into 183 distinct energy families.

  16. Magnetic Resonance Imaging System Based on Earth's Magnetic Field

    E-Print Network [OSTI]

    Stepi?nik, Janez

    Magnetic Resonance Imaging System Based on Earth's Magnetic Field Ales Mohoric,1,* Gorazd Planinsic magnetic field can be partly compensated by the receiving coil design and shielding of electromagnetic pick and must be monitored accurately.[8­ 10] The importance of NMR in a non-uniform magnetic field

  17. Actuation of Micro-Optomechanical Systems Via Cavity-Enhanced Optical Dipole Forces

    E-Print Network [OSTI]

    Eichenfield, M; Painter, O; Perahia, R; Eichenfield, Matt; Michael, Christopher P.; Painter, Oskar; Perahia, Raviv

    2007-01-01T23:59:59.000Z

    We demonstrate an optomechanical system employing a movable, micron-scale waveguide optically-coupled to a high-Q optical microresonator. We show that milliwatt-level optical powers create micron-scale displacements of the input waveguide. The displacement is caused by a cavity-enhanced optical dipole force (CEODF) on the waveguide, arising from the stored optical field of the resonator. The CEODF is used to demonstrate tunable cavity-waveguide coupling at sub-mW input powers, a form of all-optical tunable filter. The scaling properties of the CEODF are shown to be independent of the intrinsic Q of the optical resonator and to scale inversely with the cavity mode volume.

  18. Thermal modeling of the Tevatron magnet system

    SciTech Connect (OSTI)

    Jay C. Theilacker; Arkadiy L. Klebaner

    2004-07-20T23:59:59.000Z

    Operation of the Tevatron at lower temperatures, for the purpose of allowing higher energies, has resulted in a renewed interest in thermal modeling of the magnet strings. Static heat load and AC loses in the superconducting coils are initially transported through subcooled liquid helium. Heat exchange between the subcooled liquid and a counter flowing two-phase stream transfers the load to the latent heat. Stratification of the two-phase helium stream has resulted in considerably less heat exchange compared to the original design. Spool pieces have virtually no heat transfer to the two-phase resulting in a ''warm'' dipole just downstream. A model of the magnet string thermal behavior has been developed. The model has been used to identify temperature profiles within magnet strings. The temperature profiles are being used in conjunction with initial magnet quench performance data to predict the location of quench limiting magnets within the Tevatron. During thermal cycles of magnet strings, the model is being used to ''shuffle'' magnets within the magnet string in order to better match the magnets quench performance with its actual predicted temperature. The motivation for this analysis is to raise the operating energy of the Tevatron using a minimal number of magnets from the spares pool.

  19. Production and Detection of Axion-Like Particles in a HERA Dipole Magnet - Letter-of-Intent for the ALPS experiment -

    E-Print Network [OSTI]

    Klaus Ehret; Maik Frede; Ernst-Axel Knabbe; Dietmar Kracht; Axel Lindner; Niels Meyer; Dieter Notz; Andreas Ringwald; Guenter Wiedemann

    2007-02-13T23:59:59.000Z

    Recently, the PVLAS collaboration has reported evidence for an anomalous rotation of the polarization of light in vacuum in the presence of a transverse magnetic field. This may be explained through the production of a new light spin-zero (axion-like) neutral particle coupled to two photons. In this letter-of-intent, we propose to test this hypothesis by setting up a photon regeneration experiment which exploits the photon beam of a high-power infrared laser, sent along the transverse magnetic field of a superconducting HERA dipole magnet. The proposed ALPS (Axion-Like Particle Search) experiment offers a window of opportunity for a rapid firm establishment or exclusion of the axion-like particle interpretation of the anomaly published by PVALS. It will also allow for the measurement of mass, parity, and coupling strength of this particle. [The experiment has been approved by the DESY directorate on January 11, 2007.

  20. Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces

    E-Print Network [OSTI]

    Dewar, Robert L.

    Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces R. L. Dewar and S. R. Hudson & Engineering, The Australian National University, Canberra, A.C.T. 0200, Australia e-mail: robert-orbits, and the surfaces are formed from a continuous one-parameter family of such orbits. Magnetic field-line flow

  1. A test of a 2 Tesla superconducting transmission line magnet system

    SciTech Connect (OSTI)

    Piekarz, Henryk; Carcagno, Ruben; Claypool, Brad; Foster, George W.; Hays, Steven L.; Huang, Yuenian; Kashikhin, Vladimir; Malamud, Ernest; Mazur, Peter O.; Nehring,; Oleck, Andrew; Rabehl, Roger; Schlabach, Phil; Sylvester, Cosmore; Velev, Gueorgui; Volk, James; /Fermilab; Wake, Masayoshi; /KEK, Tsukuba

    2005-09-01T23:59:59.000Z

    Superconducting transmission line magnet test system for an injector accelerator of a staged VLHC proton-proton colliding beam accelerator has been built and operated at Fermilab. The 1.5 m long, twin-aperture, combined function dipole magnet of 2 Tesla field is excited by a single turn 100 kA transmission line superconductor. The 100 kA dc current is generated using dc-dc switching converters powered by a bulk 240 kW supply. A pair of horizontally placed conventional leads facilitates transfer of this current to the magnet transmission line superconductor operating at liquid helium temperature. Fabrication of magnet components and magnet assembly work are described. The magnet test system and its operation are presented, and the performance is summarized.

  2. Dipole induced transparency in drop-filter cavity-waveguide systems

    E-Print Network [OSTI]

    Edo Waks; Jelena Vuckovic

    2005-12-05T23:59:59.000Z

    We show that a waveguide that is normally opaque due to interaction with a drop-filter cavity can be made transparent when the drop filter is also coupled to a dipole. A transparency condition is derived between the cavity lifetime and vacuum Rabi frequency of the dipole. This condition is much weaker than strong coupling, and amounts to simply achieving large Purcell factors. Thus, we can observe transparency in the weak coupling regime. We describe how this effect can be useful for designing quantum repeaters for long distance quantum communication.

  3. The measurement and analysis of the magnetic field of a synchrotron light source magnet 

    E-Print Network [OSTI]

    Graf, Udo Werner

    1994-01-01T23:59:59.000Z

    In this thesis a unique system is used to measure the magnetic field of a superconducting synchrotron light source magnet. The magnet measured is a superferric dipole C-magnet designed to produce a magnetic field up to 3 Tesla in magnitude. Its...

  4. VOLUME 83, NUMBER 15 P H Y S I C A L R E V I E W L E T T E R S 11 OCTOBER 1999 Large Contributions of Negative-Energy States to Forbidden Magnetic-Dipole Transition

    E-Print Network [OSTI]

    Johnson, Walter R.

    of Negative-Energy States to Forbidden Magnetic-Dipole Transition Amplitudes in Alkali-Metal Atoms I. M, Notre Dame, Indiana 46556 (Received 20 May 1999) The influence of negative-energy states (NES) on forbidden magnetic-dipole ns1 2 2 n 1 1 s1 2 transitions in alkali-metal atoms is investigated. We find

  5. Axion Induced Oscillating Electric Dipole Moments

    E-Print Network [OSTI]

    Hill, Christopher T

    2015-01-01T23:59:59.000Z

    The axion electromagnetic anomaly induces an oscillating electric dipole for any static magnetic dipole. Static electric dipoles do not produce oscillating magnetic moments. This is a low energy theorem which is a consequence of the space-time dependent cosmic background field of the axion. The electron will acquire an oscillating electric dipole of frequency $m_a$ and strength $\\sim 10^{-32}$ e-cm, two orders of magnitude above the nucleon, and within four orders of magnitude of the present standard model DC limit. This may suggest sensitive new experimental venues for the axion dark matter search.

  6. Magnetic QCA systems G.H. Bernsteina,

    E-Print Network [OSTI]

    Metlushko, Vitali

    Magnetic QCA systems G.H. Bernsteina, *, A. Imrea , V. Metlushkoc , A. Orlova , L. Zhoua , L. Jia in an altogether new paradigm. Magnetic interactions between nanomagnets are sufficiently strong to allow room recent work of the Notre Dame group on magnetically coupled QCA. q 2005 Elsevier Ltd. All rights reserved

  7. Magnetic induction systems to harvest energy from mechanical vibrations

    E-Print Network [OSTI]

    Jonnalagadda, Aparna S

    2007-01-01T23:59:59.000Z

    This thesis documents the design process for magnetic induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. ...

  8. Cooling system for superconducting magnet

    DOE Patents [OSTI]

    Gamble, B.B.; Sidi-Yekhlef, A.

    1998-12-15T23:59:59.000Z

    A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir. 3 figs.

  9. Superconducting Magnet Division

    E-Print Network [OSTI]

    Ohta, Shigemi

    Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R.6 A gun collectors gun Combined Horizontal and Vertical Corrector Design Both types of dipole correctors. Gupta, M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A

  10. DESIGN OF EPOXY-FREE SUPERCONDUCTING DIPOLE MAGNETS AND PERFORMANCE IN BOTH HELIUM I AND PRESSURIZED HELIUM II

    E-Print Network [OSTI]

    Taylor, C.

    2010-01-01T23:59:59.000Z

    Exchange I " L ^ v v / / / / > > y^ffHn Helium II cryostatWarren et. al. , "A Pressurized Helium H-Cooled Magnet Testin Pressurized Superfluid Helium", CXS 40 11th International

  11. Magnetic-field-dosimetry system

    DOE Patents [OSTI]

    Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

    1981-01-21T23:59:59.000Z

    A device is provided for measuring the magnetic field dose and peak field exposure. The device includes three Hall-effect sensors all perpendicular to each other, sensing the three dimensional magnetic field and associated electronics for data storage, calculating, retrieving and display.

  12. Helium Catalyzed D-D Fusion in a Levitated Dipole

    E-Print Network [OSTI]

    instead of the magnetic shear and average good curvature. As a result, a dipole magnetic field can confinement. We find that a dipole based D-D power source can provide better utilization of magnetic field-D design w Plasma parameters w High Tc floating coil; neutronics, refrigeration ˙ Compare with DT tokamak

  13. Sensitivity and Accuracy of the Systems for the Magnetic Measurements of the LHC Magnets at CERN

    E-Print Network [OSTI]

    Bottura, L; Schnizer, P; Smirnov, N; Walckiers, L

    2000-01-01T23:59:59.000Z

    Beam optics of the LHC accelerator require stringent control of the field quality of the main dipole and quadrupole magnets. The field quality measurements need challenging accuracy given the small size of the aperture (50 mm) : relative strength of the magnets within 2×10-4, harmonics in the ppm range, axis determination within 0.1 mm, main field direction within 0.2 mrad. We present a detailed analysis of the accuracy and reproducibility obtained with the equipment presently available for the qualification tests of the first series magnets.

  14. MICE Spectrometer Magnet System Progress

    SciTech Connect (OSTI)

    Green, Michael A.; Virostek, Steve P.

    2007-08-27T23:59:59.000Z

    The first magnets for the muon ionization cooling experimentwill be the tracker solenoids that form the ends of the MICE coolingchannel. The primary purpose of the tracker solenoids is to provide auniform 4 T field (to better than +-0.3 percent over a volume that is 1meter long and 0.3 meters in diameter) spectrometer magnet field for thescintillating fiber detectors that are used to analyze the muons in thechannel before and after ionization cooling. A secondary purpose for thetracker magnet is the matching of the muon beam between the rest of theMICE cooling channel and the uniform field spectrometer magnet. Thetracker solenoid is powered by three 300 amp power supplies. Additionaltuning of the spectrometer is provided by a pair of 50 amp power suppliesacross the spectrometer magnet end coils. The tracker magnet will becooled using a pair of 4 K pulse tube coolers that each provide 1.5 W ofcooling at 4.2 K. Final design and construction of the tracker solenoidsbegan during the summer of 2006. This report describes the progress madeon the construction of the tracker solenoids.

  15. Final Report: Levitated Dipole Experiment

    SciTech Connect (OSTI)

    Kesner, Jay; Mauel, Michael

    2013-03-10T23:59:59.000Z

    Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier, Phys. Plasmas, v13, p. 056111, 2006]. High-beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability makes LDX the longest pulse fusion confinement experiment now operating in the U.S. fusion program. In both supported and levitated configurations, detailed measurements are made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma is created by multifrequency electron cyclotron resonance heating allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole is levitated or supported, the peak thermal electron temperature is estimated to exceed 500 eV and peak densities reach 1.0E18 (1/m3). Several significant discoveries resulted from the routine investigation of plasma confinement with a magnetically-levitated dipole. For the first time, toroidal plasma with pressure approaching the pressure of the confining magnetic field was well-confined in steady-state without a toroidal magnetic field. Magnetic levitation proved to be reliable and is now routine. The dipole's cryostat allows up to three hours of "float time" between re-cooling with liquid helium and providing scientists unprecedented access to the physics of magnetizd plasma. Levitation eliminates field-aligned particle sources and sinks and results in a toroidal, magnetically-confined plasma where profiles are determined by cross-field transport. We find levitation causes the central plasma density to increase dramatically and to significantly improve the confinement of thermal plasma [Boxer, Nature-Physics, v8, p. 949, 2010]. Several diagnostic systems have been used to measure plasma fluctuations, and these appear to represent low-frequency convection that may lead to adiabatic heating and strongly peaked pressure profiles. These experiments are remarkable, and the motivate wide-ranging studies of plasma found in space and confined for fusion energy. In the following report, we describe: (i) observations of the centrally-peaked density profile that appears naturally as a consequence of a strong turbulent pinch, (ii) observations of overall density and pressure increases that suggest large improvements to the thermal electron confinement time result occur during levitation, and (iii) the remarkable properties of low-frequency plasma fluctuations that cause magnetized plasma to "self-organize" into well-confined, centrally-peaked profiles that are relative to fusion and to space.

  16. SUPERCONDUCTING COMBINED FUNCTION MAGNET SYSTEM FOR J-PARC NEUTRINO EXPERIMENT.

    SciTech Connect (OSTI)

    OGITSU, T.; AJIMA, Y.; ANERELLA, M.; ESCALLIER, J.; GANETIS, G.; GUPTA, R.; HAGEDOM, D.; HARRISON, M.; HIGASHI, N.; IWAMOTO, Y.; ICHIKAWA, A.; JAIN, A.; KIMURA, N.; KOBAYASHI, T.; MAKIDA, Y.; MURATORE, J.; NAKAMOTO, T.; OHHATA, H.; TAKASAKI, N.; TANAKA, K.; TERASHIMA, A.; YAMOMOTO, A.; OBANA, T.; PARKER, B.; WANDERER, P.

    2004-10-03T23:59:59.000Z

    The J-PARC Neutrino Experiment, the construction of which starts in JFY 2004, will use a superconducting magnet system for its primary proton beam line. The system, which bends the 50 GeV 0.75 MW proton beam by about 80 degrees, consists of 28 superconducting combined function magnets. The magnets utilize single layer left/right asymmetric coils that generate a dipole field of 2.6 T and a quadrupole field of 18.6 T/m with the operation current of about 7.35 kA. The system also contains a few conduction cooled superconducting corrector magnets that serve as vertical and horizontal steering magnets. All the magnets are designed to provide a physical beam aperture of 130 mm in order to achieve a large beam acceptance. Extensive care is also required to achieve safe operation with the high power proton beam. The paper summarizes the system design as well as some safety analysis results.

  17. Instrumentation status of the low-b magnet systems at the Large Hadron Collider (LHC)

    SciTech Connect (OSTI)

    Darve, C.; /Fermilab; Balle, C.; Casas-Cubillos, J.; Perin, A.; Vauthier, N.; /CERN

    2011-05-01T23:59:59.000Z

    The low-{beta} magnet systems are located in the Large Hadron Collider (LHC) insertion regions around the four interaction points. They are the key elements in the beams focusing/defocusing process allowing proton collisions at luminosity up to 10{sup 34}cm{sup -2}s{sup -1}. Those systems are a contribution of the US-LHC Accelerator project. The systems are mainly composed of the quadrupole magnets (triplets), the separation dipoles and their respective electrical feed-boxes (DFBX). The low-{beta} magnet systems operate in an environment of extreme radiation, high gradient magnetic field and high heat load to the cryogenic system due to the beam dynamic effect. Due to the severe environment, the robustness of the diagnostics is primordial for the operation of the triplets. The hardware commissioning phase of the LHC was completed in February 2010. In the sake of a safer and more user-friendly operation, several consolidations and instrumentation modifications were implemented during this commissioning phase. This paper presents the instrumentation used to optimize the engineering process and operation of the final focusing/defocusing quadrupole magnets for the first years of operation.

  18. Design and Fabrication of a Single-Aperture 11T Nb3Sn Dipole Model for LHC Upgrades

    SciTech Connect (OSTI)

    Andreev, N.; Apollinari, G.; Barzi, E.; Bossert, R.; Nobrega, F.; Novitski, I.; Turrioni, D.; Yamada, R.; Zlobin, A.V.; /Fermilab; Auchmann, B.; Karppinen, M.; /CERN

    2011-11-28T23:59:59.000Z

    The planned upgrade of the LHC collimation system includes additional collimators to be installed in the dispersion suppressor areas of points 2, 3 and 7. To provide the necessary longitudinal space for the collimators, a replacement of 8.33 T Nb-Ti LHC main dipoles with 11 T dipoles based on Nb{sub 3}Sn superconductor compatible with the LHC lattice and main systems is being considered. To demonstrate this possibility FNAL and CERN have started a joint program to develop a 2 m long single-aperture dipole magnet with the nominal field of 11 T at {approx}11.85 kA current and 60 mm bore. This paper describes the demonstrator magnet magnetic and mechanical designs and analysis, coil fabrication procedure. The Nb{sub 3}Sn strand and cable parameters and test results are also reported.

  19. Axion Induced Oscillating Electric Dipole Moments

    E-Print Network [OSTI]

    Christopher T. Hill

    2015-04-10T23:59:59.000Z

    The axion electromagnetic anomaly induces an oscillating electric dipole for {\\em any} static magnetic dipole. Static electric dipoles do not produce oscillating magnetic moments. This is a low energy theorem which is a consequence of the space-time dependent cosmic background field of the axion in the limit that it is only locally time dependent $(\\overrightarrow{\\beta}=0)$. The electron will acquire an oscillating electric dipole of frequency $m_a$ and strength $\\sim 10^{-32}$ e-cm, three orders of magnitude above the nucleon, and within four orders of magnitude of the present standard model DC limit. This may suggest sensitive new experimental venues for the axion dark matter search.

  20. Application of Chebyshev Formalism to Identify Nonlinear Magnetic Field Components in Beam Transport Systems

    SciTech Connect (OSTI)

    Michael Spata

    2012-08-01T23:59:59.000Z

    An experiment was conducted at Jefferson Lab's Continuous Electron Beam Accelerator Facility to develop a beam-based technique for characterizing the extent of the nonlinearity of the magnetic fields of a beam transport system. Horizontally and vertically oriented pairs of air-core kicker magnets were simultaneously driven at two different frequencies to provide a time-dependent transverse modulation of the beam orbit relative to the unperturbed reference orbit. Fourier decomposition of the position data at eight different points along the beamline was then used to measure the amplitude of these frequencies. For a purely linear transport system one expects to find solely the frequencies that were applied to the kickers 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. Chebyshev polynomials and their unique properties allow one to directly quantify the magnitude of the nonlinearity with the minimum error. A calibration standard was developed using one of the sextupole magnets in a CEBAF beamline. The technique was then applied to a pair of Arc 1 dipoles and then to the magnets in the Transport Recombiner beamline to measure their multipole content as a function of transverse position within the magnets.

  1. New baseline for the magnet cooling system Yury Ivanyushenkov

    E-Print Network [OSTI]

    McDonald, Kirk

    1 New baseline for the magnet cooling system Yury Ivanyushenkov Engineering and Instrumentation Department, Rutherford Appleton Laboratory #12;2 Liquid nitrogen cooling system: Conceptual points · Magnet the magnet as a stand alone system. #12;3 Liquid nitrogen cooling system: Diagram Drawn by Peter Titus #12

  2. 15 T And Beyond - Dipoles and Quadrupoles

    SciTech Connect (OSTI)

    Sabbi, GianLuca

    2008-05-19T23:59:59.000Z

    Starting with the invention of the cyclotron by Lawrence, accelerator-based experiments have been the primary source of new discoveries in particle physics. In order to progress toward higher energy and luminosity, higher field magnets are required. R&D programs are underway to take advantage of new developments in superconducting materials, achieve better efficiency and simplify magnet fabrication while preserving accelerator-class field quality. A review of recent progress on high field dipole and quadrupole magnets is presented.

  3. Trapped field internal dipole superconducting motor generator

    DOE Patents [OSTI]

    Hull, John R. (Downers Grove, IL)

    2001-01-01T23:59:59.000Z

    A motor generator including a high temperature superconductor rotor and an internally disposed coil assembly. The motor generator superconductor rotor is constructed of a plurality of superconductor elements magnetized to produce a dipole field. The coil assembly can be either a conventional conductor or a high temperature superconductor. The superconductor rotor elements include a magnetization direction and c-axis for the crystals of the elements and which is oriented along the magnetization direction.

  4. Dipole-Dipole coupled double Rydberg molecules

    E-Print Network [OSTI]

    Martin Kiffner; Hyunwook Park; Wenhui Li; Tom F. Gallagher

    2012-05-21T23:59:59.000Z

    We show that the dipole-dipole interaction between two Rydberg atoms can give rise to long range molecules. The binding potential arises from two states that converge to different separated atom asymptotes. These states interact weakly at large distances, but start to repel each other strongly as the van der Waals interaction turns into a resonant dipole-dipole interaction with decreasing separation between the atoms. This mechanism leads to the formation of an attractive well for one of the potentials. If the two separated atom asymptotes come from the small Stark splitting of an atomic Rydberg level, which lifts the Zeeman degeneracy, the depth of the well and the location of its minimum are controlled by the external electric field. We discuss two different geometries that result in a localized and a donut shaped potential, respectively.

  5. Structural analysis of superconducting dipole prototype for HIAF

    E-Print Network [OSTI]

    Zhang, Xiaoying; Ni, Dongsheng; Chen, Yuquan; Wu, Wei; Ma, Lizhen

    2015-01-01T23:59:59.000Z

    The High Intensity Heavy-Ion Accelerator Facility is a new project in the Institute of Modern Physics. The dipole magnets of all rings are conceived as fast cycled superconducting magnet with high magnetic field and large gap, the warm iron and superconducting coil structure (superferric) is adopted. The reasonable structure design of coil and cryostat is very important for reliable operation. Based on the finite element software ANSYS, the mechanical analysis of electromagnetic stress, the thermal stress in the cooling down and the stress in the pumping are showed in detail. According to the analysis result, the supporter structure is the key problem of coil system. With reasonable support's structure design, the stress and the deformation of coil structure can be reduced effectively, which ensure the stable operation of superconducting coil system.

  6. Magnetic Energy Storage System: Superconducting Magnet Energy Storage System with Direct Power Electronics Interface

    SciTech Connect (OSTI)

    None

    2010-10-01T23:59:59.000Z

    GRIDS Project: ABB is developing an advanced energy storage system using superconducting magnets that could store significantly more energy than today’s best magnetic storage technologies at a fraction of the cost. This system could provide enough storage capacity to encourage more widespread use of renewable power like wind and solar. Superconducting magnetic energy storage systems have been in development for almost 3 decades; however, past devices were designed to supply power only for short durations—generally less than a few minutes. ABB’s system would deliver the stored energy at very low cost, making it ideal for eventual use in the electricity grid as a costeffective competitor to batteries and other energy storage technologies. The device could potentially cost even less, on a per kilowatt basis, than traditional lead-acid batteries.

  7. A Testbed of Magnetic Induction-based Communication System for Underground Applications

    E-Print Network [OSTI]

    Tan, Xin; Akyildiz, Ian F

    2015-01-01T23:59:59.000Z

    Wireless underground sensor networks (WUSNs) can enable many important applications such as intelligent agriculture, pipeline fault diagnosis, mine disaster rescue, concealed border patrol, crude oil exploration, among others. The key challenge to realize WUSNs is the wireless communication in underground environments. Most existing wireless communication systems utilize the dipole antenna to transmit and receive propagating electromagnetic (EM) waves, which do not work well in underground environments due to the very high material absorption loss. The Magnetic Induction (MI) technique provides a promising alternative solution that could address the current problem in underground. Although the MI-based underground communication has been intensively investigated theoretically, to date, seldom effort has been made in developing a testbed for the MI-based underground communication that can validate the theoretical results. In this paper, a testbed of MI-based communication system is designed and implemented in a...

  8. Novel Dipole Trapped Spheromak Configuration M. R. Brown,1,

    E-Print Network [OSTI]

    Brown, Michael R.

    Novel Dipole Trapped Spheromak Configuration M. R. Brown,1, * C. D. Cothran,1 J. Fung,1 M. J. Schaffer,2 and E. Belova3 We report the observation and characterization of a spheromak formed in the Swarthmore Spheromak Experiment (SSX) and trapped in a simple dipole magnetic field. The spheromak is studied

  9. Self-adjusting magnetic bearing systems

    DOE Patents [OSTI]

    Post, R.F.

    1998-07-21T23:59:59.000Z

    A self-adjusting magnetic bearing automatically adjusts the parameters of an axially unstable magnetic bearing such that its force balance is maintained near the point of metastable equilibrium. Complete stabilization can be obtained with the application of weak restoring forces either from a mechanical bearing (running at near-zero load, thus with reduced wear) or from the action of residual eddy currents in a snubber bearing. In one embodiment, a torque is generated by the approach of a slotted pole to a conducting plate. The torque actuates an assembly which varies the position of a magnetic shunt to change the force exerted by the bearing. Another embodiment achieves axial stabilization by sensing vertical displacements in a suspended bearing element, and using this information in an electrical servo system. In a third embodiment, as a rotating eddy current exciter approaches a stationary bearing, it heats a thermostat which actuates an assembly to weaken the attractive force between the two bearing elements. An improved version of an electromechanical battery utilizing the designs of the various embodiments is described. 7 figs.

  10. Self-adjusting magnetic bearing systems

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1998-01-01T23:59:59.000Z

    A self-adjusting magnetic bearing automatically adjusts the parameters of an axially unstable magnetic bearing such that its force balance is maintained near the point of metastable equilibrium. Complete stabilization can be obtained with the application of weak restoring forces either from a mechanical bearing (running at near-zero load, thus with reduced wear) or from the action of residual eddy currents in a snubber bearing. In one embodiment, a torque is generated by the approach of a slotted pole to a conducting plate. The torque actuates an assembly which varies the position of a magnetic shunt to change the force exerted by the bearing. Another embodiment achieves axial stabilization by sensing vertical displacements in a suspended bearing element, and using this information in an electrical servo system. In a third embodiment, as a rotating eddy current exciter approaches a stationary bearing, it heats a thermostat which actuates an assembly to weaken the attractive force between the two bearing elements. An improved version of an electromechanical battery utilizing the designs of the various embodiments is described.

  11. Design development for the 50mm Superconducting Super Collider dipole cryostat

    SciTech Connect (OSTI)

    Nicol, T.H.

    1991-03-01T23:59:59.000Z

    The cryostat of a Superconducting Super Collider (SSC) dipole magnet consists of all magnet components except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course their expected operating life. This paper describes the design of the current 50mm SSC collider dipole cryostat and includes discussions on the structural and thermal considerations involved in the development of each of the major systems. Where appropriate, comparisons will be made with the 40mm cryostat. 7 refs., 5 figs., 4 tabs.

  12. Dipole-Dipole Resistivity At Blue Mountain Geothermal Area (Ross...

    Open Energy Info (EERE)

    GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Dipole-Dipole Resistivity At Blue Mountain Geothermal Area (Ross, Et Al., 1999) Exploration Activity Details Location...

  13. Dipole-Dipole Resistivity At Blue Mountain Geothermal Area (Fairbank...

    Open Energy Info (EERE)

    Fairbank Engineering Ltd, 2003) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Activity: Dipole-Dipole Resistivity At Blue Mountain Geothermal Area...

  14. ac dipole design: Topics by E-print Network

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

    the dipoles for the Muon Collider should be able to handle 0.5 kWm of dynamic heat load from the muon beam decays. The magnets are based on Nb3Sn superconductor and...

  15. Ion--dipole scattering: The differential cross section for the K/sup +/--CsCl system

    SciTech Connect (OSTI)

    Budenholzer, F.E.; Gislason, E.A.; Polak-Dingels, P.

    1982-05-15T23:59:59.000Z

    The total differential cross section has been measured for K/sup +/ scattered by CsCl over the range 10< or =Etheta< or =2000 eV deg. Classical perturbation scattering theory calculations for a realistic intermolecular potential have also been carried out and agree well with the experiments. The results show that the scattering is dominated at small angles by the ion--dipole potential and at large angles by the spherically symmetric part of the repulsive potential. No rainbow scattering is observed.

  16. SSC dipole log manget model cryostat design and initial production experience

    SciTech Connect (OSTI)

    Niemann, R.C.; Carson, J.A.; Engler, N.H.; Gonczy, J.D.; Nicol, T.H.

    1986-06-01T23:59:59.000Z

    The SSC dipole magnet development program includes the design and construction of full length magnet models for heat leak and magnetic measurements and for the evaluation of the performance of strings of magnets. The design of the model magnet cryostat is presented and the production experiences for the initial long magnet model, a heat leak measurement device, are related.

  17. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, H.J.

    1984-05-16T23:59:59.000Z

    It is an object of the present invention to provide superconducting magnetic energy storage for a plurality of asynchronous electrical systems. It is a further object of the present invention to provide load leveling and stability improvement in a plurality of independent ac systems using a single superconducting magnetic energy storage coil.

  18. Low-field classroom nuclear magnetic resonance system

    E-Print Network [OSTI]

    Zimmerman, Clarissa Lynette

    2010-01-01T23:59:59.000Z

    The goal of this research was to develop a Low-field Classroom NMR system that will enable hands-on learning of NMR and MRI concepts in a Biological-Engineering laboratory course. A permanent magnet system, designed using ...

  19. HTS High Gradient Magnetic Separation system

    SciTech Connect (OSTI)

    Daugherty, M.A.; Coulter, J.Y.; Hults, W.L. [and others

    1996-09-01T23:59:59.000Z

    We report on the assembly, characterization and operation of a high temperature superconducting (HTS) magnetic separator. The magnet is made of 624 m of Silver/BSCCO superconducting wire and has overall dimensions of 18 cm OD, 15.5 cm height and 5 cm ID. The HTS current leads are designed to operate with the warm end at 75 K and the cold end cooled by a two stage Gifford-McMahon cryocooler. The upper stage of the cryocooler cools the thermal shield and two heat pipe thermal intercepts. The lower stage of the cryocooler cools the HTS magnet and the bottom end of the HTS current leads. The HTS magnet was initially characterized in liquid cryogens. We report on the current- voltage (I-V) characteristics of the HTS magnet at temperatures ranging from 15 to 40 K. At 40 K the magnet can generate a central field of 2.0 T at a current of 120 A.

  20. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, R.F.

    1998-03-03T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds. 7 figs.

  1. Magnetic levitation system for moving objects

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    1998-01-01T23:59:59.000Z

    Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces are applied to magnetically levitate a moving object such as a train car. The power required to levitate a train of such cars is drawn from the motional energy of the train itself, and typically represents only a percent or two of the several megawatts of power required to overcome aerodynamic drag at high speeds.

  2. Ris-R-1578(EN) Design of MgB2 superconducting dipole

    E-Print Network [OSTI]

    Risř-R-1578(EN) Design of MgB2 superconducting dipole magnet for particle beam transport-C. Grivel1 and N.H. Andersen1 Title: Design of MgB2 superconducting dipole magnet for particle beam. 2000 char.): A comprehensive analysis of the innovation potential of superconductivity at Risř

  3. Noncommutative Dipole Field Theories

    E-Print Network [OSTI]

    K. Dasgupta; M. M. Sheikh-Jabbari

    2002-02-05T23:59:59.000Z

    Assigning an intrinsic constant dipole moment to any field, we present a new kind of associative star product, the dipole star product, which was first introduced in [hep-th/0008030]. We develop the mathematics necessary to study the corresponding noncommutative dipole field theories. These theories are sensible non-local field theories with no IR/UV mixing. In addition we discuss that the Lorentz symmetry in these theories is ``softly'' broken and in some particular cases the CP (and even CPT) violation in these theories may become observable. We show that a non-trivial dipole extension of N=4, D=4 gauge theories can only be obtained if we break the SU(4) R (and hence super)-symmetry. Such noncommutative dipole extensions, which in the maximal supersymmetric cases are N=2 gauge theories with matter, can be embedded in string theory as the theories on D3-branes probing a smooth Taub-NUT space with three form fluxes turned on or alternatively by probing a space with R-symmetry twists. We show the equivalences between the two approaches and also discuss the M-theory realization.

  4. Power-Invariant Magnetic System Modeling 

    E-Print Network [OSTI]

    Gonzalez Dominguez, Guadalupe Giselle

    2012-10-19T23:59:59.000Z

    : the reluctance, as analogous to the electric resistance, should be a dissipative element instead it is an energy storage element. Furthermore, the two other elements are not defined. This difference has initiated a reevaluation of the conventional magnetic model...

  5. A SUPERCONDUCTING MAGNET SYSTEM FOR THE SPIRIT COSMIC RAY SPACE TELESCOPE

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    secondary circuit*® NbVSh superconducting coils ElectricalAugust 21-24, 1979 A SUPERCONDUCTING MAGNET SYSTEM FOR THETELESCOPE MASTER A SUPERCONDUCTING MAGNET SYSTEM FOR THE

  6. Final Exam 2010 1) A point magnetic dipole m is located in vacuum pointing away from and a distance d away from a semi-infinite

    E-Print Network [OSTI]

    Glashausser, Charles

    is attractive. (5 points) 2) A wire coil is wound around the surface of a solid sphere of radius a and permeability µ. The magnetic potential outside the sphere has the form of a multipole moment (r > a) = Iµ µ + µ

  7. Permanent magnet electron beam ion source/trap systems with bakeable magnets for improved operation conditions

    SciTech Connect (OSTI)

    Schmidt, M., E-mail: mike.schmidt@dreebit.com [DREEBIT GmbH, 01109 Dresden (Germany); Zschornack, G.; Kentsch, U.; Ritter, E. [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)] [Department of Physics, Dresden University of Technology, 01062 Dresden, Germany and Helmholtz-Zentrum Dresden-Rossendorf e.V., Institute of Ion Beam Physics and Materials Research, 01328 Dresden (Germany)

    2014-02-15T23:59:59.000Z

    The magnetic system of a Dresden electron beam ion source (EBIS) generating the necessary magnetic field with a new type of permanent magnet made of high energy density NdFeB-type material operable at temperatures above 100?°C has been investigated and tested. The employment of such kind of magnets provides simplified operation without the time-consuming installation and de-installation procedures of the magnets for the necessary baking of the ion source after commissioning and maintenance work. Furthermore, with the use of a new magnetization technique the geometrical filling factor of the magnetic Dresden EBIS design could be increased to a filling factor of 100% leading to an axial magnetic field strength of approximately 0.5 T exceeding the old design by 20%. Simulations using the finite element method software Field Precision and their results compared with measurements are presented as well. It could be shown that several baking cycles at temperatures higher than 100?°C did not change the magnetic properties of the setup.

  8. A scalable electro-magnetic communication system for underwater swarms

    E-Print Network [OSTI]

    Zimmer, Uwe

    A scalable electro-magnetic communication system for underwater swarms Felix Schill 1 Uwe R. Zimmer for communication is small compared to propulsion requirements. Communication of state information can there- fore

  9. Theory of Dipole Induced Electromagnetic Transparency

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

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

  10. Superconducting magnetic energy storage for asynchronous electrical systems

    DOE Patents [OSTI]

    Boenig, Heinrich J. (Los Alamos, NM)

    1986-01-01T23:59:59.000Z

    A superconducting magnetic energy storage coil connected in parallel between converters of two or more ac power systems provides load leveling and stability improvement to any or all of the ac systems. Control is provided to direct the charging and independently the discharging of the superconducting coil to at least a selected one of the ac power systems.

  11. Coherent dipole-dipole coupling between two single atoms at a Förster resonance

    E-Print Network [OSTI]

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

    2014-05-30T23:59:59.000Z

    Resonant energy transfers, i.e. 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 chemical and biological phenomena, most notably photosynthesis. In 1948, F\\"orster established the theoretical basis of fluorescence resonant energy transfer (FRET), paving the ground towards the widespread use of FRET as a "spectroscopic ruler" for the determination of nanometer-scale distances in biomolecules. The underlying mechanism is a coherent dipole-dipole coupling between particles, as already recognized in the early days of quantum mechanics, but this coherence was not directly observed so far. Here, we study, both spectroscopically and in the time domain, the coherent, dipolar-induced exchange of electronic excitations between two single Rydberg atoms separated by a controlled distance as large as 15 microns, and brought into resonance by applying a small electric field. The coherent oscillation of the system between two degenerate pair states occurs at a frequency that scales as the inverse third power of the distance, the hallmark of dipole-dipole interactions. Our results not only demonstrate, at the most 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.

  12. Final Report: Levitated Dipole Experiment

    SciTech Connect (OSTI)

    Kesner, Jay [Massachusetts Institute of Technology; Mauel, Michael [Columbia University

    2013-03-10T23:59:59.000Z

    Since the very first experiments with the LDX, research progress was rapid and significant. Initial experiments were conducted with the high-field superconducting coil suspended by three thin rods. These experiments produced long-pulse, quasi-steady-state microwave discharges, lasting more than 10 s, having peak beta values of 20% [Garnier et al., Physics of Plasmas, 13 (2006) 056111]. High- beta, near steady-state discharges have been maintained in LDX for more than 20 seconds, and this capability made LDX the longest pulse fusion confinement experiment operating in the U.S. fusion program. A significant measure of progress in the LDX research program was the routine investigation of plasma confinement with a magnetically-levitated dipole and the resulting observations of confinement improvement. In both supported and levitated configurations, detailed measurements were made of discharge evolution, plasma dynamics and instability, and the roles of gas fueling, microwave power deposition profiles, and plasma boundary shape. High-temperature plasma was created by multi frequency electron cyclotron resonance heating at 2.45 GHz, 6.4 GHz, 10.5 GHz and 28 GHz allowing control of heating profiles. Depending upon neutral fueling rates, the LDX discharges contain a fraction of energetic electrons, with mean energies above 50 keV. Depending on whether or not the superconducting dipole was levitated or supported, the peak thermal electron temperature was estimated to exceed 500 eV and peak densities to approach 1e18 m?3. We have found that levitation causes a strong inwards density pinch [Boxer et al., Nature Physics, 6 (2010) 207] and we have observed the central plasma density increase dramatically indicating a significant improvement in the confinement of a thermal plasma species.

  13. A hybrid data acquisition system for magnetic measurements of accelerator magnets

    SciTech Connect (OSTI)

    Wang, X.; Hafalia, R.; Joseph, J.; Lizarazo, J.; Martchevsky, M.; Sabbi, G. L.

    2011-06-03T23:59:59.000Z

    A hybrid data acquisition system was developed for magnetic measurement of superconducting accelerator magnets at LBNL. It consists of a National Instruments dynamic signal acquisition (DSA) card and two Metrolab fast digital integrator (FDI) cards. The DSA card records the induced voltage signals from the rotating probe while the FDI cards records the flux increment integrated over a certain angular step. This allows the comparison of the measurements performed with two cards. In this note, the setup and test of the system is summarized. With a probe rotating at a speed of 0.5 Hz, the multipole coefficients of two magnets were measured with the hybrid system. The coefficients from the DSA and FDI cards agree with each other, indicating that the numerical integration of the raw voltage acquired by the DSA card is comparable to the performance of the FDI card in the current measurement setup.

  14. Dipole nano-laser: Theory and properties

    SciTech Connect (OSTI)

    Ghannam, T., E-mail: gtalal@hotmail.com [King Abdullah Institute for Nano-Technology, King Saud University, PO Box 2454, Riyadh 11451 (Saudi Arabia)

    2014-03-31T23:59:59.000Z

    In this paper we outline the main quantum properties of the system of nano-based laser called Dipole Nano-Laser emphasizing mainly on its ability to produce coherent light and for different configurations such as different embedding materials and subjecting it to an external classical electric field.

  15. Superconducting Magnet Division

    E-Print Network [OSTI]

    Gupta, Ramesh

    Superconducting Magnet Division Permanent Magnet Designs with Large Variations in Field Strength the residual field of the magnetized bricks by concentrating flux lines at the iron pole. Low Field Design Medium Field Design Superconducting Magnet Division Dipole and Quadrupole Magnets for RHIC e

  16. Oscillation damping means for magnetically levitated systems

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2009-01-20T23:59:59.000Z

    The present invention presents a novel system and method of damping rolling, pitching, or yawing motions, or longitudinal oscillations superposed on their normal forward or backward velocity of a moving levitated system.

  17. Magnetic Fields in Quantum Degenerate Systems and in Vacuum

    E-Print Network [OSTI]

    H. Perez Rojas; E. Rodriguez Querts

    2006-12-28T23:59:59.000Z

    We consider self-magnetization of charged and neutral vector bosons bearing a magnetic moment in a gas and in vacuum. For charged vector bosons (W bosons) a divergence of the magnetization in both the medium and the electroweak vacuum occurs for the critical field B=B_{wc}=m_{w}^{2}/e. For B>B_{wc} the system is unstable. This behavior suggests the occurrence of a phase transition at B=B_{c}, where the field is self-consistently maintained. This mechanism actually prevents $B$ from reaching the critical value B_{c}. For virtual neutral vector bosons bearing an anomalous magnetic moment, the ground state has a similar behavior for B=B_{nbc}=m_{nb}^{2}/q . The magnetization in the medium is associated to a Bose-Einstein condensate and we conjecture a similar condensate occurs also in the case of vacuum. The model is applied to virtual electron-positron pairs bosonization in a magnetic field B \\sim B_{pc}\\lesssim 2m_{e}^{2}/e, where m_e is the electron mass. This would lead also to vacuum self-magnetization in QED, where in both cases the symmetry breaking is due to a condensate of quasi-massless particles.

  18. Developmentof the 15 T Nb3Sn dipole HD2

    SciTech Connect (OSTI)

    Caspi, S.; Cheng, D.W.; Dietderich, D.R.; Hafalia, A.R.; Hannaford, C.R.; Higley, H.; Lietzke, A.F.; Lizarazo, J.; McInturff, A.D.; Sabbi, G.; Ferracin, P.

    2008-06-01T23:59:59.000Z

    The Superconducting Magnet Program at Lawrence Berkeley National Laboratory (LBNL) is continuing the development of HD2, a 1 m long Nb{sub 3}Sn dipole generating a dipole field of 15 T in a 36 mm clear bore. With tilted (flared) ends to avoid obstructing the beam path, HD2 represents a step towards the development of cost effective accelerator quality magnets. The design has been optimized to minimize geometric harmonics and to address iron saturation and conductor magnetization effects. The support structure is based on an external aluminum shell, pre-tensioned with pressurized bladders and interference keys. Aluminum axial rods and stainless steel end plates provide longitudinal support to the coil ends during magnet excitation. This paper reports on field quality optimization and magnet parameters. The design and fabrication of the coil and structure components, and results from coil winding, reaction, and potting are also presented.

  19. Assuring safety in high-speed magnetically levitated (maglev) systems : the need for a system safety approach

    E-Print Network [OSTI]

    Ota, Shuichiro Daniel

    2008-01-01T23:59:59.000Z

    Magnetic levitation is a railway technology that enables vehicles to be magnetically suspended above their tracks. Although this technology is still under development, magnetically levitated (maglev) systems have great ...

  20. Dipole-strength

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

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOEThe Bonneville Power AdministrationField Campaign: Potential ApplicationYu,EnergyDimitri KusnezovDipole-strength

  1. Power-Invariant Magnetic System Modeling

    E-Print Network [OSTI]

    Gonzalez Dominguez, Guadalupe Giselle

    2012-10-19T23:59:59.000Z

    System Modeling. (August 2011) Guadalupe Giselle González Domínguez, B.S., Universidad Tecnológica de Panamá Chair of Advisory Committee: Dr. Mehrdad Ehsani In all energy systems, the parameters necessary to calculate power are the same..., Mr. R. Smith, Mr. S. Emani and Mr. R. Castillo, for making my time at Texas A&M University a great experience. I also want to extend my gratitude to Dr. Darío Solís and Dr. Edilberto Hall at the Universidad Tecnológica de Panamá for their guidance...

  2. Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration

    SciTech Connect (OSTI)

    None

    2010-09-01T23:59:59.000Z

    BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics’ design uses a novel property of certain materials, called “magnetocaloric materials”, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses no ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.

  3. Magnetic field diffusion modeling of a small enclosed firing system

    SciTech Connect (OSTI)

    Warne, L.K.; Merewether, K.O.

    1996-01-01T23:59:59.000Z

    Intense magnetic fields exist in the immediate vicinity of a lightning strike (and near power lines). Conducting barriers increase the rise time (and thus decrease the rise rate) interior to the barrier, but typically do not prevent penetration of the magnetic field, since the lightning current fall time may be larger than the barrier diffusion time. Thus, substantial energy is present in the interior field, although the degradation of rise rate makes it more difficult to couple into electrical circuits. This report assesses the threat posed by the diffusive magnetic field to interior components and wire loops (where voltages are induced). Analytical and numerical bounding analyses are carried out on a pill box shaped conducting barrier to develop estimates for the worst case magnetic field threats inside the system. Worst case induced voltages and energies are estimated and compared with threshold charge voltages and energies on the output capacitor of the system. Variability of these quantities with respect to design parameters are indicated. The interior magnetic field and induced voltage estimates given in this report can be used as excitations for more detailed interior and component models.

  4. DISTURBANCE ATTENUATION IN A MAGNETIC LEVITATION SYSTEM WITH

    E-Print Network [OSTI]

    Nagurka, Mark L.

    and inherently nonlinear. Feedback control loops are used to manipulate the electromagnetic forces strategies. Shan and Menq [1] reported two disturbance rejection algorithms-- internal model-based control] reported a position regulation control strategy developed for a magnetic levitation system operating

  5. Fifth-order aberrations in magnetic quadrupole-octupole systems

    SciTech Connect (OSTI)

    Ling, K.M.

    1990-01-01T23:59:59.000Z

    Explicit integral expressions are given for the fifth-order geometrical aberration coefficients in rectilinear magnetic quadrupole-octupole systems used for the transport of nonrelativistic charged particle beams. The numerical values of the fifth-order geometrical aberration coefficients for a rare earth cobalt (REC) quadrupole doublet are given as an example. 26 refs., 5 figs., 4 tabs.

  6. Direct amplitude detuning measurement with ac dipole

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

    White, S.; Maclean, E.; Tomás, R.

    2013-07-01T23:59:59.000Z

    In circular machines, nonlinear dynamics can impact parameters such as beam lifetime and could result in limitations on the performance reach of the accelerator. Assessing and understanding these effects in experiments is essential to confirm the accuracy of the magnetic model and improve the machine performance. A direct measurement of the machine nonlinearities can be obtained by characterizing the dependency of the tune as a function of the amplitude of oscillations (usually defined as amplitude detuning). The conventional technique is to excite the beam to large amplitudes with a single kick and derive the tune from turn-by-turn data acquired with beam position monitors. Although this provides a very precise tune measurement it has the significant disadvantage of being destructive. An alternative, nondestructive way of exciting large amplitude oscillations is to use an ac dipole. The perturbation Hamiltonian in the presence of an ac dipole excitation shows a distinct behavior compared to the free oscillations which should be correctly taken into account in the interpretation of experimental data. The use of an ac dipole for direct amplitude detuning measurement requires careful data processing allowing one to observe the natural tune of the machine; the feasibility of such a measurement is demonstrated using experimental data from the Large Hadron Collider. An experimental proof of the theoretical derivations based on measurements performed at injection energy is provided as well as an application of this technique at top energy using a large number of excitations on the same beam.

  7. Characterization of low-frequency density fluctuations in dipole-confined laboratory plasmas

    E-Print Network [OSTI]

    Ellsworth, Jennifer L

    2010-01-01T23:59:59.000Z

    Low-frequency fluctuations of plasma density, floating potential, ion saturation current, visible light intensity, and edge magnetic field are routinely observed in the Levitated Dipole Experiment (LDX). For the purposes ...

  8. Derivation of Generalized Thomas-Bargmann-Michel-Telegdi Equation for a Particle with Electric Dipole Moment

    E-Print Network [OSTI]

    Takeshi Fukuyama; Alexander J. Silenko

    2013-11-09T23:59:59.000Z

    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.

  9. Solenoid magnet system for the Fermilab Mu2e experiment

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

    Lamm, M J; Andreev, N; Ambrosio, G; Brandt, J; Coleman, R; Evbota, D; Kashikhin, V V; Lopes, M; Miller, J; Nicol, T; et al

    2012-06-08T23:59:59.000Z

    The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an 'S shaped' transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoidmore »at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion elections. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented.« less

  10. Solenoid magnet system for the Fermilab Mu2e experiment

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

    Lamm, M J [Fermilab; Andreev, N [Fermilab /Boston U.; Ambrosio, G [Fermilab; Brandt, J [Fermilab; Coleman, R [CERN; Evbota, D [Fermilab; Kashikhin, V V [City Coll., N.Y.; Lopes, M [Fermilab; Miller, J [Fermilab; Nicol, T [KEK; Ostojic, R [Tsukuba

    2012-06-08T23:59:59.000Z

    The Fermilab Mu2e experiment seeks to measure the rare process of direct muon to electron conversion in the field of a nucleus. Key to the design of the experiment is a system of three superconducting solenoids; a muon production solenoid (PS) which is a 1.8 m aperture axially graded solenoid with a peak field of 5 T used to focus secondary pions and muons from a production target located in the solenoid aperture; an 'S shaped' transport solenoid (TS) which selects and transports the subsequent muons towards a stopping target; a detector solenoid (DS) which is an axially graded solenoid at the upstream end to focus transported muons to a stopping target, and a spectrometer solenoid at the downstream end to accurately measure the momentum of the outgoing conversion elections. The magnetic field requirements, the significant magnetic coupling between the solenoids, the curved muon transport geometry and the large beam induced energy deposition into the superconducting coils pose significant challenges to the magnetic, mechanical, and thermal design of this system. In this paper a conceptual design for the magnetic system which meets the Mu2e experiment requirements is presented.

  11. Magnetic resonance imaging of living systems by remote detection

    DOE Patents [OSTI]

    Wemmer, David; Pines, Alexander; Bouchard, Louis; Xu, Shoujun; Harel, Elad; Budker, Dmitry; Lowery, Thomas; Ledbetter, Micah

    2013-10-29T23:59:59.000Z

    A novel approach to magnetic resonance imaging is disclosed. Blood flowing through a living system is prepolarized, and then encoded. The polarization can be achieved using permanent or superconducting magnets. The polarization may be carried out upstream of the region to be encoded or at the place of encoding. In the case of an MRI of a brain, polarization of flowing blood can be effected by placing a magnet over a section of the body such as the heart upstream of the head. Alternatively, polarization and encoding can be effected at the same location. Detection occurs at a remote location, using a separate detection device such as an optical atomic magnetometer, or an inductive Faraday coil. The detector may be placed on the surface of the skin next to a blood vessel such as a jugular vein carrying blood away from the encoded region.

  12. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, Robert G. (Barrington Hills, IL)

    1998-01-01T23:59:59.000Z

    A magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly.

  13. High performance magnetic bearing systems using high temperature superconductors

    DOE Patents [OSTI]

    Abboud, R.G.

    1998-05-05T23:59:59.000Z

    Disclosed are a magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly. 7 figs.

  14. A superconducting dipole magnet for laser spectroscopy 

    E-Print Network [OSTI]

    Wagenhauser, Kenneth Edward

    1990-01-01T23:59:59.000Z

    consists of two halves, each with 36 layers of wire, each layer containing 14 coils, for a total of 100S turns. Each layer is independently coiled, and either soldeted or cold-welded to the next layer. The resistance of these joints is expected... to be on the order of 10 9 and 10 7 ohms, respectively 9 The coils are mounted in a laminated iron cladding which, in addition to providing structural stability, dramatically reduces the field outside of the core by promoting flux return. 10 A welded stainless...

  15. PERFORMANCE OF DIPOLE MAGNETS IN HELIUM II

    E-Print Network [OSTI]

    Althaus, R.

    2010-01-01T23:59:59.000Z

    R. Meuser, J. Rechen, C. Taylor, and R. Warren March 1981R. Mauser, J. ROCIMM, C. Taylor, R. Mirren Licence Berkeley

  16. PROSPECTS FOR 10T ACCELERATOR DIPOLE MAGNETS

    E-Print Network [OSTI]

    Taylor, C.E.

    2010-01-01T23:59:59.000Z

    With careful design, the heat input to the 1.8K region canstations, L(m): for a given heat input along the conduit of

  17. Superconducting magnetic control system for manipulation of particulate matter and magnetic probes in medical and industrial applications

    DOE Patents [OSTI]

    Cha, Yung Sheng; Hull, John R.; Askew, Thomas R.

    2006-07-11T23:59:59.000Z

    A system and method of controlling movement of magnetic material with at least first and second high temperature superconductors at spaced locations. A plurality of solenoids are associated with the superconductors to induce a persistent currents in preselected high temperature superconductors establishing a plurality of magnetic fields in response to pulsed currents introduced to one or more of the solenoids. Control mechanism in communication with said solenoids and/or said high temperature superconductors are used to demagnetize selected ones of the high temperature superconductors to reduce the magnetic fields substantially to zero. Magnetic material is moved between magnetic fields by establishing the presence thereof and thereafter reducing magnetic fields substantially to zero and establishing magnetic fields in other superconductors arranged in a predetermined configuration.

  18. Abstract--Magnetic Resonance Imaging (MRI) guided nanorobotic systems that could perform diagnostic, curative

    E-Print Network [OSTI]

    Mavroidis, Constantinos

    groups have employed magnetized micro/ nanoparticles and have implemented magnetic propulsion techniquesAbstract-- Magnetic Resonance Imaging (MRI) guided nanorobotic systems that could perform on the use of a MRI scanner to induce the required external driving forces to guide magnetic nanocapsules

  19. A review of dynamic characteristics of magnetically levitated vehicle systems

    SciTech Connect (OSTI)

    Cai, Y.; Chen, S.S.

    1995-11-01T23:59:59.000Z

    The dynamic response of magnetically levitated (maglev) ground transportation systems has important consequences for safety and ride quality, guideway design, and system costs. Ride quality is determined by vehicle response and by environmental factors such as humidity and noise. The dynamic response of the vehicles is the key element in determining ride quality, while vehicle stability is an important safety-related element. To design a guideway that provides acceptable ride quality in the stable region, vehicle dynamics must be understood. Furthermore, the trade-off between guideway smoothness and levitation and control systems must be considered if maglev systems are to be economically feasible. The link between the guideway and the other maglev components is vehicle dynamics. For a commercial maglev system, vehicle dynamics must be analyzed and tested in detail. This report, which reviews various aspects of the dynamic characteristics, experiments and analysis, and design guidelines for maglev systems, discusses vehicle stability, motion dependent magnetic force components, guideway characteristics, vehicle/ guideway interaction, ride quality, suspension control laws, aerodynamic loads and other excitations, and research needs.

  20. Confined System with Rashba Coupling in Constant Magnetic Field

    E-Print Network [OSTI]

    Mohammed El Bouziani; Rachid Houca; Ahmed Jellal

    2012-04-30T23:59:59.000Z

    We study a two dimensional system of electrons with Rashba coupling in the constant magnetic field $B$ and confining potential. We algebraically diagonalize the corresponding Hamiltonian to end up with the solutions of the energy spectrum. In terms of two kinds of operator we construct two symmetries and discuss the filling of the shells with electrons for strong and weak $B$. Subsequently, we show that our system is sharing some common features with quantum optics where the exact operator solutions for the basics Jaynes-Cummings variables are derived from our results. An interesting limit is studied and the corresponding quantum dynamics is recovered.

  1. Reliability analysis for LEB ring magnet power system in SSC

    SciTech Connect (OSTI)

    Smedley, K.

    1991-11-01T23:59:59.000Z

    The LEB ring magnet power system contains six subsystems, supervisory control, power supplies, regulation, DC bus, resonant cells, and fault sensing network. The system availability of the total LEB RMPS is required to be 0.999. The work in this paper is to allocate the overall LEB RMPS reliability requirement into reliability requirements for each of the subsystems and lower-tier items. The Feasibility-of-Objective technique combining with engineering experience is the key for the allocation. MIL-HDBK-217F is used to derate SCR components. 7 refs., 5 figs.

  2. System having unmodulated flux locked loop for measuring magnetic fields

    DOE Patents [OSTI]

    Ganther, Jr., Kenneth R. (Olathe, KS); Snapp, Lowell D. (Blue Springs, MO)

    2006-08-15T23:59:59.000Z

    A system (10) for measuring magnetic fields, wherein the system (10) comprises an unmodulated or direct-feedback flux locked loop (12) connected by first and second unbalanced RF coaxial transmission lines (16a, 16b) to a superconducting quantum interference device (14). The FLL (12) operates for the most part in a room-temperature or non-cryogenic environment, while the SQUID (14) operates in a cryogenic environment, with the first and second lines (16a, 16b) extending between these two operating environments.

  3. Progress on Levitation in the Levitated Dipole Experiment

    E-Print Network [OSTI]

    detection system prototype complete Catcher system under construction Levitation system testing in progress and cooling requirements AC heating introduces unique requirements for control system Large 5 m diameterProgress on Levitation in the Levitated Dipole Experiment D.T. Garnier, M.E. Mauel, T. Sunn

  4. Fusion Engineering and Design 80 (2006) 139160 ARIES-AT magnet systems

    E-Print Network [OSTI]

    California at San Diego, University of

    2006-01-01T23:59:59.000Z

    Fusion Engineering and Design 80 (2006) 139­160 ARIES-AT magnet systems F. Dahlgrenb,, T. Brownb, P the physics and the engineering are more aggressive. The design of the toroidal field magnet is slightly less Available online 21 October 2005 Abstract This report presents a conceptual design of the magnet systems

  5. 13th International Conference on Magnetically Levitated Systems and Linear Drives

    SciTech Connect (OSTI)

    Not Available

    1993-09-01T23:59:59.000Z

    This report contains short papers on research being conducted throughout the world on magnetically levitated systems, mainly consisting of trains, and magnetic linear drives. These papers have been index separately elsewhere on the data base.

  6. DC Resistivity Survey (Dipole-Dipole Array) At Waunita Hot Springs...

    Open Energy Info (EERE)

    dipoles at each station. Injected currents of 6-8 amperes and a filtering frequency of 3.0 Hz were used. The profile dipole survey used a dipole with a length of 200 feet and...

  7. Molten metal feed system controlled with a traveling magnetic field

    DOE Patents [OSTI]

    Praeg, Walter F. (Palos Park, IL)

    1991-01-01T23:59:59.000Z

    A continuous metal casting system in which the feed of molten metal is controlled by means of a linear induction motor capable of producing a magnetic traveling wave in a duct that connects a reservoir of molten metal to a caster. The linear induction motor produces a traveling magnetic wave in the duct in opposition to the pressure exerted by the head of molten metal in the reservoir so that p.sub.c =p.sub.g -p.sub.m where p.sub.c is the desired pressure in the caster, p.sub.g is the gravitational pressure in the duct exerted by the force of the head of molten metal in the reservoir, and p.sub.m is the electromagnetic pressure exerted by the force of the magnetic field traveling wave produced by the linear induction motor. The invention also includes feedback loops to the linear induction motor to control the casting pressure in response to measured characteristics of the metal being cast.

  8. Expansion joint for guideway for magnetic levitation transportation system

    DOE Patents [OSTI]

    Rossing, T.D.

    1993-02-09T23:59:59.000Z

    An expansion joint that allows a guideway of a magnetic levitation transportation system to expand and contract while minimizing transients occurring in the magnetic lift and drag forces acting on a magnetic levitation vehicle traveling over the joint includes an upper cut or recess extending downwardly from the upper surface of the guideway and a non-intersecting lower cut or recess that extends upwardly from the lower surface of the guideway. The side walls of the cuts can be parallel to each other and the vertical axis of the guideway; the depth of the lower cut can be greater than the depth of the upper cut; and the overall combined lengths of the cuts can be greater than the thickness of the guideway from the upper to lower surface so that the cuts will overlap, but be spaced apart from each other. The distance between the cuts can be determined on the basis of the force transients and the mechanical behavior of the guideway. A second pair of similarly configured upper and lower cuts may be disposed in the guideway; the expansion joint may consist of two upper cuts and one lower cut; or the cuts may have non-parallel, diverging side walls so that the cuts have a substantially dove-tail shape.

  9. Expansion joint for guideway for magnetic levitation transportation system

    DOE Patents [OSTI]

    Rossing, Thomas D. (DeKalb, IL)

    1993-01-01T23:59:59.000Z

    An expansion joint that allows a guideway of a magnetic levitation transportation system to expand and contract while minimizing transients occurring in the magnetic lift and drag forces acting on a magnetic levitation vehicle traveling over the joint includes an upper cut or recess extending downwardly from the upper surface of the guideway and a non-intersecting lower cut or recess that extends upwardly from the lower surface of the guideway. The sidewalls of the cuts can be parallel to each other and the vertical axis of the guideway; the depth of the lower cut can be greater than the depth of the upper cut; and the overall combined lengths of the cuts can be greater than the thickness of the guideway from the upper to lower surface so that the cuts will overlap, but be spaced apart from each other. The distance between the cuts can be determined on the basis of the force transients and the mechanical behavior of the guideway. A second pair of similarly configured upper and lower cuts may be disposed in the guideway; the expansion joint may consist of two upper cuts and one lower cut; or the cuts may have non-parallel, diverging sidewalls so that the cuts have a substantially dove-tail shape.

  10. Modeling spin magnetization transport in a spatially varying magnetic field

    E-Print Network [OSTI]

    Rico A. R. Picone; Joseph L. Garbini; John A. Sidles

    2014-08-13T23:59:59.000Z

    We present a framework for modeling the transport of any number of globally conserved quantities in any spatial configuration and apply it to obtain a model of magnetization transport for spin-systems that is valid in new regimes (including high-polarization). The framework allows an entropy function to define a model that explicitly respects the laws of thermodynamics. Three facets of the model are explored. First, it is expressed as nonlinear partial differential equations that are valid for the new regime of high dipole-energy and polarization. Second, the nonlinear model is explored in the limit of low dipole-energy (semi-linear), from which is derived a physical parameter characterizing separative magnetization transport (SMT). It is shown that the necessary and sufficient condition for SMT to occur is that the parameter is spatially inhomogeneous. Third, the high spin-temperature (linear) limit is shown to be equivalent to the model of nuclear spin transport of Genack and Redfield. Differences among the three forms of the model are illustrated by numerical solution with parameters corresponding to a magnetic resonance force microscopy (MRFM) experiment. A family of analytic, steady-state solutions to the nonlinear equation is derived and shown to be the spin-temperature analog of the Langevin paramagnetic equation and Curie's law. Finally, we analyze the separative quality of magnetization transport, and a steady-state solution for the magnetization is shown to be compatible with Fenske's separative mass transport equation.

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

    E-Print Network [OSTI]

    Jordi Mur-Petit; Juan José García-Ripoll

    2015-01-12T23:59:59.000Z

    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.

  12. Development of Nb3Sn 11 T single aperture demonstrator dipole for LHC upgrades

    SciTech Connect (OSTI)

    Zlobin, A.V.; Apollinari, G.; Andreev, N.; Barzi, E.; Kashikhin, V.V.; Nobrega, f.; Novitski, I.; /Fermilab; Auchmann, B.; Karppinen, M.; Rossi, L.; /CERN

    2011-03-01T23:59:59.000Z

    The LHC collimation upgrade foresees additional collimators installed in dispersion suppressor regions. To obtain the necessary space for the collimators, a solution based on the substitution of LHC main dipoles for stronger dipoles is being considered. CERN and FNAL have started a joint program to demonstrate the feasibility of Nb{sub 3}Sn technology for this purpose. The goal of the first phase is the design and construction of a 2-m long single-aperture demonstrator magnet with a nominal field of 11 T at 11.85 kA with 20% margin. This paper describes the magnetic and mechanical design of the demonstrator magnet and summarizes its design parameters.

  13. Alternative Approach to the Provision of the High-field Dipole for FCC-hh

    E-Print Network [OSTI]

    Taylor, Thomas

    2015-01-01T23:59:59.000Z

    This paper describes a possible approach to reducing the complexity and cost of the high field dipole magnets. In addition the cooling of the winding could be improved in the proposed design, with a consequent reduction in the shielding requirements. The correction of multipoles is also addressed: this feature may impact on the dynamic range of operation of the magnets. Noting that it would be possible to add a small gradient component to the dipole, it is suggested that a (partially) combined function lattice should be considered. The proposals lead to a brief re-appraisal of how best to apply superconductivity to magnets for large accelerators.

  14. Methods, systems and devices for detecting threatening objects and for classifying magnetic data

    DOE Patents [OSTI]

    Kotter, Dale K. (Shelley, ID); Roybal, Lyle G. (Idaho Falls, ID); Rohrbaugh, David T. (Idaho Falls, ID); Spencer, David F. (Idaho Falls, ID)

    2012-01-24T23:59:59.000Z

    A method for detecting threatening objects in a security screening system. The method includes a step of classifying unique features of magnetic data as representing a threatening object. Another step includes acquiring magnetic data. Another step includes determining if the acquired magnetic data comprises a unique feature.

  15. Fusion Engineering and Design 38 (1997) 159188 ARIES-RS magnet systems

    E-Print Network [OSTI]

    1997-01-01T23:59:59.000Z

    Fusion Engineering and Design 38 (1997) 159­188 ARIES-RS magnet systems L. Bromberg a, *, P. Titus and engineering data bases. In contrast with ARIES-I [1], with a high magnetic field and aggressive engineering. The engineering approach to evaluate the magnet issues for ARIES-RS is simi- lar to that of ARIES-II and ARIES

  16. Polymerase chain reaction system using magnetic beads for analyzing a sample that includes nucleic acid

    DOE Patents [OSTI]

    Nasarabadi, Shanavaz (Livermore, CA)

    2011-01-11T23:59:59.000Z

    A polymerase chain reaction system for analyzing a sample containing nucleic acid includes providing magnetic beads; providing a flow channel having a polymerase chain reaction chamber, a pre polymerase chain reaction magnet position adjacent the polymerase chain reaction chamber, and a post pre polymerase magnet position adjacent the polymerase chain reaction chamber. The nucleic acid is bound to the magnetic beads. The magnetic beads with the nucleic acid flow to the pre polymerase chain reaction magnet position in the flow channel. The magnetic beads and the nucleic acid are washed with ethanol. The nucleic acid in the polymerase chain reaction chamber is amplified. The magnetic beads and the nucleic acid are separated into a waste stream containing the magnetic beads and a post polymerase chain reaction mix containing the nucleic acid. The reaction mix containing the nucleic acid flows to an analysis unit in the channel for analysis.

  17. Prompt dipole radiation in fusion reactions

    E-Print Network [OSTI]

    Brunella Martin; Dimitra Pierroutsakou; Concetta Agodi; Rosa Alba; Virgil Baran; Alfonso Boiano; Giuseppe Cardella; Maria Colonna; Rosa Coniglione; Enrico De Filippo; Antonio Del Zoppo; Massimo Di Toro; Gianni Inglima; Tudor Glodariu; Marco La Commara; Concetta Maiolino; Marco Mazzocco; Angelo Pagano; Paolo Piattelli; Sara Pirrone; Carmelo Rizzo; Mauro Romoli; Mario Sandoli; Domenico Santonocito; Piera Sapienza; Cosimo Signorini

    2007-10-08T23:59:59.000Z

    The prompt gamma ray emission was investigated in the 16A MeV energy region by means of the 36,40Ar+96,92Zr fusion reactions leading to a compound nucleus in the vicinity of 132Ce. We show that the prompt radiation, which appears to be still effective at such a high beam energy, has an angular distribution pattern consistent with a dipole oscillation along the symmetry axis of the dinuclear system. The data are compared with calculations based on a collective bremsstrahlung analysis of the reaction dynamics.

  18. Gravity waves from vortex dipoles and jets

    E-Print Network [OSTI]

    Wang, Shuguang

    2009-05-15T23:59:59.000Z

    The dissertation first investigates gravity wave generation and propagation from jets within idealized vortex dipoles using a nonhydrostatic mesoscale model. Several initially balanced and localized jets induced by vortex dipoles are examined here...

  19. Collapse of Bose-Einstein condensates with dipole-dipole interactions Pavel M. Lushnikov*

    E-Print Network [OSTI]

    Lushnikov, Pavel

    * Theoretical Division, Los Alamos National Laboratory, MS-B284, Los Alamos, New Mexico 87545 and Landau. The net contribution of dipole-dipole interactions can be either repulsive positive dipole-dipole interactions can dominate provided polar molecules are oriented by strong enough electric field. Simi- lar

  20. Using fiberglass volumes for VPI of superconductive magnetic systems’ insulation

    SciTech Connect (OSTI)

    Andreev, I. S.; Bezrukov, A. A.; Pischugin, A. B. [Sredne-Nevskiy Shipyard (SNSZ), 10 Zavodskaya str., c. Pontonniy, Saint-Petersburg (Russian Federation); Bursikov, A. S.; Klimchenko, Y. A.; Marushin, E. L.; Mednikov, A. A.; Rodin, I. Y.; Stepanov, D. B. [The D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), 3 Doroga na Metallostroy, Metallostroy, Saint-Petersburg (Russian Federation)

    2014-01-29T23:59:59.000Z

    The paper describes the method of manufacturing fiberglass molds for vacuum pressure impregnation (VPI) of high-voltage insulation of superconductive magnetic systems (SMS) with epoxidian hot-setting compounds. The basic advantages of using such vacuum volumes are improved quality of insulation impregnation in complex-shaped areas, and considerable cost-saving of preparing VPI of large-sized components due to dispensing with the stage of fabricating a metal impregnating volume. Such fiberglass vacuum molds were used for VPI of high-voltage insulation samples of an ITER reactor’s PF1 poloidal coil. Electric insulation of these samples has successfully undergone a wide range of high-voltage and mechanical tests at room and cryogenic temperatures. Some results of the tests are also given in this paper.

  1. SPIN POLARIZED PHOTOELECTRON SPECTROSCOPY AS A PROBE OF MAGNETIC SYSTEMS.

    SciTech Connect (OSTI)

    JOHNSON, P.D.; GUNTHERODT, G.

    2006-11-01T23:59:59.000Z

    Spin-polarized photoelectron spectroscopy has developed into a versatile tool for the study of surface and thin film magnetism. In this chapter, we examine the methodology of the technique and its recent application to a number of different problems. We first examine the photoemission process itself followed by a detailed review of spin-polarization measurement techniques and the related experimental requirements. We review studies of spin polarized surface states, interface states and quantum well states followed by studies of the technologically important oxide systems including half-metallic transition metal oxides, ferromagnet/oxide interfaces and the antiferromagnetic cuprates that exhibit high Tc Superconductivity. We also discuss the application of high-resolution photoemission with spin resolving capabilities to the study of spin dependent self energy effects.

  2. Novel Hall sensors developed for magnetic field imaging systems.

    SciTech Connect (OSTI)

    Cambel, V.; Karapetrov, G.; Novosad, V.; Bartolome, E.; Gregusova, D.; Fedor, J.; Kudela, R.; Soltys, J.; Materials Science Division; Slovak Academy of Sciences; Univ. Autonoma de Barcelona

    2007-09-01T23:59:59.000Z

    We report here on the fabrication and application of novel planar Hall sensors based on shallow InGaP/AlGaAs/GaAs heterostructure with a two-dimensional electron gas (2DEG) as an active layer. The sensors are developed for two kinds of experiments. In the first one, magnetic samples are placed directly on the Hall sensor. Room temperature experiments of permalloy objects evaporated onto the sensor are presented. In the second experiment, the sensor scans close over a multigranular superconducting sample prepared on a YBCO thin film. Large-area and high-resolution scanning experiments were performed at 4.2 K with the Hall probe scanning system in a liquid helium flow cryostat.

  3. Open-Midplane Dipoles for a Muon Collider

    SciTech Connect (OSTI)

    Weggel, R.; Gupta, R.; Kolonko, J., Scanlan, R., Cline, D., Ding, X., Anerella, M., Kirk, H., Palmer, B., Schmalzle, J.

    2011-03-28T23:59:59.000Z

    For a muon collider with copious decay particles in the plane of the storage ring, open-midplane dipoles (OMD) may be preferable to tungsten-shielded cosine-theta dipoles of large aperture. The OMD should have its midplane completely free of material, so as to dodge the radiation from decaying muons. Analysis funded by a Phase I SBIR suggests that a field of 10-20 T should be feasible, with homogeneity of 1 x 10{sup -4} and energy deposition low enough for conduction cooling to 4.2 K helium. If funded, a Phase II SBIR would refine the analysis and build and test a proof-of-principle magnet. A Phase I SBIR has advanced the feasibility of open-midplane dipoles for the storage ring of a muon collider. A proposed Phase II SBIR would refine these predictions of stresses, deformations, field quality and energy deposition. Design optimizations would continue, leading to the fabrication and test, for the first time, of a proof-of-principle dipole of truly open-midplane design.

  4. Active dipole clusters: from helical motion to fission

    E-Print Network [OSTI]

    Andreas Kaiser; Katarina Popowa; Hartmut Löwen

    2015-05-29T23:59:59.000Z

    The structure of a finite particle cluster is typically determined by total energy minimization. Here we consider the case where a cluster of soft sphere dipoles becomes active, i.e. when the individual particles exhibit an additional self-propulsion along their dipole moments. We numerically solve the overdamped equations of motion for soft-sphere dipoles in a solvent. Starting from an initial metastable dipolar cluster, the self-propulsion generates a complex cluster dynamics. The final cluster state has in general a structure widely different to the initial one, the details depend on the model parameters and on the protocol of how the self-propulsion is turned on. The center-of-mass of the cluster moves on a helical path, the details of which are governed by the initial cluster magnetization. An instantaneous switch to a high self-propulsion leads to fission of the cluster. However, fission does not occur if the self-propulsion is increased slowly to high strengths. Our predictions can be verified through experiments with self-phoretic colloidal Janus-particles and for macroscopic self-propelled dipoles in a highly viscous solvent.

  5. Direct measurement of the impulse in a magnetic thrust chamber system for laser fusion rocket

    SciTech Connect (OSTI)

    Maeno, Akihiro; Yamamoto, Naoji; Nakashima, Hideki [Interdisciplinary Graduate School of Engineering Science, Kyushu University, 6-1 Kasuga-kouen, Kasuga, Fukuoka 816-8580 (Japan); Fujioka, Shinsuke; Johzaki, Tomoyuki [Institute of Laser Engineering, Osaka University, Suita, Osaka 565-087 (Japan); Mori, Yoshitaka [Graduate School for the Creation of New Photonics Industries, Hamamatsu, Shizuoka 431-1202 (Japan); Sunahara, Atsushi [Institute for Laser Technology, Suita, Osaka 565-087 (Japan)

    2011-08-15T23:59:59.000Z

    An experiment is conducted to measure an impulse for demonstrating a magnetic thrust chamber system for laser fusion rocket. The impulse is produced by the interaction between plasma and magnetic field. In the experiment, the system consists of plasma and neodymium permanent magnets. The plasma is created by a single-beam laser aiming at a polystyrene spherical target. The impulse is 1.5 to 2.2 {mu}Ns by means of a pendulum thrust stand, when the laser energy is 0.7 J. Without magnetic field, the measured impulse is found to be zero. These results indicate that the system for generating impulse is working.

  6. Magnetic chicane for terahertz management

    DOE Patents [OSTI]

    Benson, Stephen (Yorktown, VA); Biallas, George Herman (Yorktown, VA); Douglas, David (Yorktown, VA); Jordan, Kevin Carl (Newport News, VA); Neil, George R. (Williamsburg, VA); Michelle D. Shinn (Newport News, VA); Willams, Gwyn P. (Yorktown, VA)

    2010-12-28T23:59:59.000Z

    The introduction of a magnetic electron beam orbit chicane between the wiggler and the downstream initial bending dipole in an energy recovering Linac alleviates the effects of radiation propagated from the downstream bending dipole that tend to distort the proximate downstream mirror of the optical cavity resonator.

  7. Engineering Magnetic nanoparticles are of interest in a variety of

    E-Print Network [OSTI]

    Chemical Engineering Abstract Magnetic nanoparticles are of interest in a variety of applications which take advantage of their manipulation using externally applied magnetic fields. Depending on the material used, these nanoparticles may possess either a freely rotating magnetic dipole or a dipole

  8. Robust Regulation for a Magnetic Levitation System* Claudio Bonivento Luca Gentili Lorenzo Marconi Roberto Naldi

    E-Print Network [OSTI]

    Sontag, Eduardo

    of input constraint and an internal model-based regulator is designed. Keywords: Nonlinear Output Regulation, Magnetic Lev- itation System, Complementary Current Condition, Robust Control, Saturated FeedbackRobust Regulation for a Magnetic Levitation System* Claudio Bonivento Luca Gentili Lorenzo Marconi

  9. Classical crystal formation of dipoles in two dimensions

    E-Print Network [OSTI]

    Hansen, K K; Jensen, A S; Zinner, N T

    2015-01-01T23:59:59.000Z

    We consider a two-dimensional layer of dipolar particles at zero temperature in the regime of strong dipole moments. Here we can describe the system using classical methods and determine the crystal structure that minimizes the total energy. The dipoles are assumed to be aligned by an external field and we consider different orientations of the dipolar moments with respect to the two-dimensional plane of motion. We observe that when the orientation angle changes away from perpendicular and towards the plane, the crystal structure will change from a hexagonal form to one that has the dipoles sitting in equidistant rows, i.e. a striped configuration. In addition to calculating the crystal unit cell, we also consider the phonon spectrum and the speed of sound. As the orientation changes away from perpendicular the phonon spectrum develops local minima that are a result of the deformation to the crystal structure.

  10. A Single-band Cold Mass Support System for the MICE Superconducting Coupling Magnet

    SciTech Connect (OSTI)

    Wu, Hong; Wang, Li; Liu, X.K.; Liu, C.S.; Li, L.K.; Xu, Feng Yu; Jia, Lin X.; Green, Michael A.

    2008-04-02T23:59:59.000Z

    The cooling channel of the Muon Ionization Cooling Experiment (MICE) consists of eighteen superconducting solenoid coils, which are magnetically hooked together and contained in seven modules. The operations of a pair of MICE superconducting coupling magnets are affected directly by the other solenoid coils in the MICE channel. In order to meet the stringent requirement for the magnet center and axis azimuthal angle at 4.2 K, a self-centered tension-band cold mass support system with intermediate thermal interruption was applied for the MICE superconducting coupling magnet. The physical center of the magnet does not change as it is cooled down from 300 K to 4.2 K using this support system. This paper analyzed and calculated force loads on the coupling magnet under various operation modes of the MICE cooling channel. The performance parameters of a single-band cold mass support system were calculated also.

  11. Magnetic and Cryogenic Design of the MICE Coupling Solenoid Magnet System

    SciTech Connect (OSTI)

    Wang, Li; Xu, FengYu; Wu, Hong; Liu, XiaoKum; Li, LanKai; Guo, XingLong; Chen, AnBin; Green, Michael A; Li, D.R.; Virostek, Steve; Pan, H.

    2008-08-02T23:59:59.000Z

    The Muon Ionization Cooling Experiment (MICE) will demonstrate ionization cooling in a short section of a realistic cooling channel using a muon beam at Rutherford Appleton Laboratory in the UK. The coupling magnet is a superconducting solenoid mounted around four 201MHz RF cavities, which produces magnetic field up to 2.6 T on the magnet centerline to keep muons within the iris of RF cavities windows. The coupling coil with inner radius of 750mm, length of 285mm and thickness of 102.5mm will be cooled by a pair of 1.5 W at 4.2 K small coolers. This paper will introduce the updated engineering design of the coupling magnet made by ICST in China. The detailed analyses on magnetic fields, stresses induced during the processes of winding, cool down and charging, and cold mass support assembly are presented as well.

  12. Radio-frequency driven dipole-dipole interactions in spatially separated volumes

    E-Print Network [OSTI]

    Atreju Tauschinsky; C. S. E. van Ditzhuijzen; L. D. Noordam; H. B. van Linden van den Heuvell

    2008-10-14T23:59:59.000Z

    Radio-frequency (rf) fields in the MHz range are used to induce resonant energy transfer between cold Rydberg atoms in spatially separated volumes. After laser preparation of the Rydberg atoms, dipole-dipole coupling excites the 49s atoms in one cylinder to the 49p state while the 41d atoms in the second cylinder are transferred down to the 42p state. The energy exchanged between the atoms in this process is 33 GHz. An external rf-field brings this energy transfer into resonance. The strength of the interaction has been investigated as a function of amplitude (0-1 V/cm) and frequency (1-30 MHz) of the rf-field and as a function of a static field offset. Multi-photon transitions up to fifth order as well as selection rules prohibiting the process at certain fields have been observed. The width of the resonances has been reduced compared to earlier results by switching off external magnetic fields of the magneto-optical trap, making sub-MHz spectroscopy possible. All features are well reproduced by theoretical calculations taking the strong ac-Stark shift due to the rf-field into account.

  13. The Design of a RapidDischarge Varistor System for the MICE Magnet Circuits

    SciTech Connect (OSTI)

    Green, Michael A.

    2008-07-23T23:59:59.000Z

    The need for a magnet circuit discharge system, in order to protect the magnet HTS leads during a power failure, has been discussed in recent MICE reports [1], [2]. In order to rapidly discharge a magnet, one has to put enough resistance across the lead. The resistance in this case is varistor that is put across the magnet in the event of a power outage. The resistance consists of several diodes, which act as constant voltage resistors and the resistance of the cables connecting the magnets in the circuit to each other and to the power supply. In order for the rapid discharge system to work without quenching the magnets, the voltage across the magnets must be low enough so that the diodes in the quench protection circuit don't fire and cause the magnet current to bypass the superconducting coils. It is proposed that six rapid discharge varistors be installed across the three magnet circuits the power the tracker solenoids, which are connected in series. The focusing magnets, which are also connected in series would have three varistors (one for each magnet). The coupling magnets would have a varistor for each magnet. The peak voltage that is allowed per varistor depends on the number of quench protection diodes that make up the quench protection circuit for each magnet coil circuit. It is proposed that the varistors be water cooled as the magnet circuits are being discharged through them. The water cooling circuit can be supplied with tap water. The tap water flows only when the varistor temperature reaches a temperature of 45 C.

  14. System Cost Analysis for an Interior Permanent Magnet Motor

    SciTech Connect (OSTI)

    Peter Campbell

    2008-08-01T23:59:59.000Z

    The objective of this program is to provide an assessment of the cost structure for an interior permanent magnet ('IPM') motor which is designed to meet the 2010 FreedomCAR specification. The program is to evaluate the range of viable permanent magnet materials for an IPM motor, including sintered and bonded grades of rare earth magnets. The study considers the benefits of key processing steps, alternative magnet shapes and their assembly methods into the rotor (including magnetization), and any mechanical stress or temperature limits. The motor's costs are estimated for an annual production quantity of 200,000 units, and are broken out into such major components as magnetic raw materials, processing and manufacturing. But this is essentially a feasibility study of the motor's electromagnetic design, and is not intended to include mechanical or thermal studies as would be done to work up a selected design for production.

  15. Peculiarities of Ferro-Antiferroelectric Phase Transitions 9. Alternative for dipole-glass description of properties of substances with coexisting ferroelectric and antiferroelectric phases

    E-Print Network [OSTI]

    V. M. Ishchuk; V. L. Sobolev

    2010-07-01T23:59:59.000Z

    It is demonstrated that the substances with small difference in the free energies of the ferroelectric and antiferroelectric phases possess a set of properties characteristic for the so-called "dipole glasses". Possible phase diagrams of the substances that can be misguidedly attributed to glasses are discussed. Main attention has been paid to the process of long-time relaxation of physical characteristics of these compounds after their state of thermodynamic equilibrium was disturbed by external influences. The long-time relaxation along with the pronounced frequency dependence of parameters (for example, dependence of dielectric or magnetic characteristics on the frequency of measuring field) is considered as main features due to which these systems are classified as dipole glasses. Our main purpose is to call attention to the fact that one has to be cautious during the interpretation of experimental results in substances with inhomogeneous states of coexisting domains of ferroelectric and antiferroelectric phases.

  16. RECENT TEST RESULTS OF THE FAST-PULSED 4 T COS DIPOLE GSI 001.

    SciTech Connect (OSTI)

    MORITZ, G.; KAUGERTS, J.; ESCALLIER, J.; GANETIS, G.; JAIN, A.; MARONE, A.; MURATORE, J.; THOMAS, R.; WANDERER, P.; ET AL.

    2005-05-26T23:59:59.000Z

    For the FAIR-project at GSI a model dipole was built at BNL with the nominal field of 4 T and a nominal ramp rate of 1 T/S. The magnet design was similar to the RHIC dipole, with some changes for loss reduction and better cooling. The magnet was already successfully tested in a vertical cryostat, with good training behavior. Cryogenic losses were measured and first results of field harmonics were published. However, for a better understanding of the cooling process, quench currents at several ramp rates were investigated. Detailed measurements of the field harmonics at 2 T/S between 0 and 4 T were performed.

  17. Quantum superintegrable system for arbitrary spin

    E-Print Network [OSTI]

    G. Pronko

    2007-09-20T23:59:59.000Z

    In [1] was considered the superintegrable system which describes the magnetic dipole with spin 1/2 (neutron) in the field of linear current. Here we present its generalization for any spin which preserves superintegrability. The dynamical symmetry stays the same as it is for spin 1/2.

  18. Multipacting optimization of a 750 MHz rf dipole

    SciTech Connect (OSTI)

    Delayen, Jean R. [JLAB, Old Dominion University; Castillo, Alejandro [JLAB, Old Dominion University

    2014-12-01T23:59:59.000Z

    Crab crossing schemes have been proposed to re-instate luminosity degradation due to crossing angles at the interaction points in next generation colliders to avoid the use of sharp bending magnets and their resulting large synchrotron radiation generation, highly undessirable in the detector region. The rf dipole has been considered for a different set of applications in several machines, both rings and linear colliders. We present in this paper a study of the effects on the multipacting levels and location depending on geometrical variations on the design for a crabbing/deflecting application in a high current (3/0.5 A), high repetition (750 MHz) electron/proton collider, as a matter to provide a comparison point for similar applications of rf dipoles.

  19. Electric Dipole Moments: A Global Analysis

    E-Print Network [OSTI]

    Timothy Chupp; Michael Ramsey-Musolf

    2014-07-03T23:59:59.000Z

    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.

  20. Method and system for controlling a permanent magnet machine

    DOE Patents [OSTI]

    Walters, James E.

    2003-05-20T23:59:59.000Z

    Method and system for controlling the start of a permanent magnet machine are provided. The method allows to assign a parameter value indicative of an estimated initial rotor position of the machine. The method further allows to energize the machine with a level of current being sufficiently high to start rotor motion in a desired direction in the event the initial rotor position estimate is sufficiently close to the actual rotor position of the machine. A sensing action allows to sense whether any incremental changes in rotor position occur in response to the energizing action. In the event no changes in rotor position are sensed, the method allows to incrementally adjust the estimated rotor position by a first set of angular values until changes in rotor position are sensed. In the event changes in rotor position are sensed, the method allows to provide a rotor alignment signal as rotor motion continues. The alignment signal allows to align the estimated rotor position relative to the actual rotor position. This alignment action allows for operating the machine over a wide speed range.

  1. Two-dimensional nuclear magnetic resonance of quadrupolar systems

    SciTech Connect (OSTI)

    Wang, Shuanhu

    1997-09-17T23:59:59.000Z

    This dissertation describes two-dimensional nuclear magnetic resonance theory and experiments which have been developed to study quadruples in the solid state. The technique of multiple-quantum magic-angle spinning (MQMAS) is extensively reviewed and expanded upon in this thesis. Specifically, MQMAS is first compared with another technique, dynamic-angle spinning (DAS). The similarity between the two techniques allows us to extend much of the DAS work to the MQMAS case. Application of MQMAS to a series of aluminum containing materials is then presented. The superior resolution enhancement through MQMAS is exploited to detect the five- and six-coordinated aluminum in many aluminosilicate glasses. Combining the MQMAS method with other experiments, such as HETCOR, greatly expands the possibility of the use of MQMAS to study a large range of problems and is demonstrated in Chapter 5. Finally, the technique switching-angle spinning (SAS) is applied to quadrupolar nuclei to fully characterize a quadrupolar spin system in which all of the 8 NMR parameters are accurately determined. This dissertation is meant to demonstrate that with the combination of two-dimensional NMR concepts and new advanced spinning technologies, a series of multiple-dimensional NMR techniques can be designed to allow a detailed study of quadrupolar nuclei in the solid state.

  2. Feedback Control of a Permanent Magnet Biased, Homopolar Magnetic Bearing System

    E-Print Network [OSTI]

    Wadhvani, Vishal Ashok

    2011-08-08T23:59:59.000Z

    Magnetic bearings are increasingly being used in a wide variety of applications in the industry such as compressors, turbines, motors, generators etc. Also, there are different types available depending upon their construction. The research...

  3. Scaling and Optimization of Magnetic Refrigeration for Commercial Building HVAC Systems Greater than 175 kW in Capacity

    SciTech Connect (OSTI)

    Abdelaziz, Omar [ORNL] [ORNL; West, David L [ORNL] [ORNL; Mallow, Anne M [ORNL] [ORNL

    2012-01-01T23:59:59.000Z

    Heating, ventilation, air-conditioning and refrigeration (HVACR) account for approximately one- third of building energy consumption. Magnetic refrigeration presents an opportunity for significant energy savings and emissions reduction for serving the building heating, cooling, and refrigeration loads. In this paper, we have examined the magnet and MCE material requirements for scaling magnetic refrigeration systems for commercial building cooling applications. Scaling relationships governing the resources required for magnetic refrigeration systems have been developed. As system refrigeration capacity increases, the use of superconducting magnet systems becomes more applicable, and a comparison is presented of system requirements for permanent and superconducting (SC) magnetization systems. Included in this analysis is an investigation of the ability of superconducting magnet based systems to overcome the parasitic power penalty of the cryocooler used to keep SC windings at cryogenic temperatures. Scaling relationships were used to develop the initial specification for a SC magnet-based active magnetic regeneration (AMR) system. An optimized superconducting magnet was designed to support this system. In this analysis, we show that the SC magnet system consisting of two 0.38 m3 regenerators is capable of producing 285 kW of cooling power with a T of 28 K. A system COP of 4.02 including cryocooler and fan losses which illustrates that an SC magnet-based system can operate with efficiency comparable to traditional systems and deliver large cooling powers of 285.4 kW (81.2 Tons).

  4. Effect of Axial Loading on Quench Performance in Nb3Sn Magnets

    SciTech Connect (OSTI)

    Ambrosio, G.; Bordini, B.; Caspi, S.; Dietderich, D.R.; Felice, H.; Hafalia, A.R.; Hannaford, C.R.; Lizarazo, J.; Lietzke, A.F.; McInturff, A.D.; Sabbi, G.L.; DiMarco, J.D.; Tartaglia, M.; Vedrice, P.; Ferracin, P.

    2008-06-01T23:59:59.000Z

    A series of tests has been performed at Lawrence Berkeley National Laboratory (LBNL) and Fermi National Accelerator Laboratory (FNAL) with the goal of assessing the influence of coil axial pre-load on Nb{sub 3}Sn magnet training. The tests involved two subscale Nb{sub 3}Sn magnets: SQ02, a quadrupole magnet fabricated as part of the US LHC Accelerator Research Program (LARP), and SD01, a dipole magnet developed in collaboration between CEA/Saclay and LBNL. Both magnets used similar Nb{sub 3}Sn flat racetrack coils from LBNL Subscale Magnet Program, and implemented an axial support system composed of stainless steel end-plates and aluminum rods. The system was designed to withstand full longitudinal electro-magnetic forces and provide controllable preloads. Quench performances, training, and quench locations have been recorded in various axial loading conditions. Test results are reported.

  5. NLO evolution of color dipoles

    SciTech Connect (OSTI)

    Ian Balitsky; Giovanni Chirilli

    2008-01-01T23:59:59.000Z

    The small-x deep inelastic scattering in the saturation region is governed by the non-linear evolution of Wilson-lines operators. In the leading logarithmic approximation it is given by the BK equation for the evolution of color dipoles. In the next-to-leaing order the BK equation gets contributions from quark and gluon loops as well as from the tree gluon diagrams with quadratic and cubic nonlinearities. We calculate the gluon contribution to small-x evolution of Wilson lines (the quark part was obtained earlier).

  6. NLO evolution of color dipoles

    E-Print Network [OSTI]

    Ian Balitsky; Giovanni A. Chirilli

    2007-10-23T23:59:59.000Z

    The small-$x$ deep inelastic scattering in the saturation region is governed by the non-linear evolution of Wilson-line operators. In the leading logarithmic approximation it is given by the BK equation for the evolution of color dipoles. In the next-to-leading order the BK equation gets contributions from quark and gluon loops as well as from the tree gluon diagrams with quadratic and cubic nonlinearities. We calculate the gluon contribution to small-x evolution of Wilson lines (the quark part was obtained earlier).

  7. Electric dipole moments, from e to tau

    E-Print Network [OSTI]

    A. G. Grozin; I. B. Khriplovich; A. S. Rudenko

    2008-12-12T23:59:59.000Z

    We derive an upper limit on the electric dipole moment (EDM) of the tau-lepton, which follows from the precision measurements of the electron EDM.

  8. Electric dipole moments, from e to tau

    E-Print Network [OSTI]

    Grozin, A G; Rudenko, A S

    2008-01-01T23:59:59.000Z

    We derive an upper limit on the electric dipole moment (EDM) of the tau-lepton, which follows from the precision measurements of the electron EDM.

  9. Electric dipole moments, from e to {tau}

    SciTech Connect (OSTI)

    Grozin, A. G., E-mail: A.G.Grozin@inp.nsk.su; Khriplovich, I. B., E-mail: khriplovich@inp.nsk.su; Rudenko, A. S., E-mail: saber_@inbox.r [Budker Institute of Nuclear Physics (Russian Federation)

    2009-07-15T23:59:59.000Z

    We derive an upper limit on the electric dipole moment (EDM) of the {tau}-lepton, which follows from the precision measurements of the electron EDM.

  10. Effective spin-flip scattering in diffusive superconducting proximity systems with magnetic disorder

    E-Print Network [OSTI]

    Skvortsov, Mikhail

    Effective spin-flip scattering in diffusive superconducting proximity systems with magnetic superconductors and normal metals or ferromagnets with magnetic disorder. On the length scales much larger than.45. c, 75.60.Ch, 74.78.Fk I. INTRODUCTION In conventional superconductors S , pairing occurs be- tween

  11. Construction of Superconducting Magnet System for the J-PARC Neutrino Beam Line

    SciTech Connect (OSTI)

    Nakamoto, T.; Wanderer, P.; Sasaki, K.; Ajima, Y.; Araoka, O.; Fujii, Y.; Hastings, N.; Higashi, N.; Iida, M.; Ishii, T.; Kimura, N.; Kobayashi, T.; Makida, Y.; Nakadaira, T.; Ogitsu, T.; Ohhata, H.; Okamura, T.; Sakashita, K.; Sugawara, S.; Suzuki, S.; Tanaka, K.; Tomaru, T.; Terashima, A.; Yamamoto, A.; Ichikawa, A.; Kakuno, H.; Anerella, M.; Escallier, J.; Ganetis, G.; gupta, R.; Jain, A.; Muratore, J.; Parker, B.; Boussuge, T.; Charrier, J.-P.; Arakawa, M.; Ichihara, T.; Minato, T.; Okada, Y.; Itou, A.; Kumaki, T.; Nagami, M.; Takahashi, T.

    2009-10-18T23:59:59.000Z

    Following success of a prototype R&D, construction of a superconducting magnet system for J-PARC neutrino beam line has been carried out since 2005. A new conceptual beam line with the superconducting combined function magnets demonstrated the successful beam transport to the neutrino production target.

  12. System and method of operating toroidal magnetic confinement devices

    DOE Patents [OSTI]

    Chance, M.S.; Jardin, S.C.; Stix, T.H.; Grimm, R.C.; Manickam, J.; Okabayashi, M.

    1984-08-30T23:59:59.000Z

    This invention pertains to methods and arrangements for attaining high beta values in plasma confinement devices. More specifically, this invention pertains to methods for accessing the second stability region of operation in toroidal magnetic confinement devices.

  13. Support system design for a superconducting MRI magnet

    E-Print Network [OSTI]

    Watts, Louis Chad

    1993-01-01T23:59:59.000Z

    Cylindrical cold mass surrounded by an aluminum radiation shield and suspended by two stainless steel rods 2. 2 Ratio of dynamic displacement to static displacement vs. ratio of shock duration to natural period 2. 3 Ratio of dynamic displacement to static... Windmgs Axial Figure 2. 1 Cylindrical cold mass surrounded by an aluminum radiation shield and suspended by two stainless steel rods In a superconducting magnet the magnetic field is dependent on the current in the superconducting wires, the position...

  14. Overview of the bump-magnet system at the LANSCE proton storage ring

    SciTech Connect (OSTI)

    Rose, C.R.; Barlow, D.B.; Blind, B.; Neri, F.; Power, J.F.; Walstrom, P.L.

    1997-09-01T23:59:59.000Z

    An upgrade program for increasing the stored beam current in the Proton Storage is presently under way. A part of the upgrade is the design and installation of a four-magnet beam-bumping system used for phase-space painting and minimizing interaction of the stored beam with the injection stripper foil. This paper describes the bump- magnet system including the relevant beam requirements, magnet specifications, power-cable specifications, pulsed-modulator requirements, and beam-tube eddy-current effects. The magnets are ferrite window-frame magnets with saddle windings. The series-pass pulsed modulators are programmable both in rise and fall time as well as amplitude. The peak current can be varied between 50 and 300 A. The pulsed-current rise-time is fixed at 1 ms, and the linear fall- time during which beam is injected into the ring can be varied between 0.5 and 1.5 ms.

  15. Thermodynamics of finite magnetic two-isomer systems Peter Borrmann, Heinrich Stamerjohanns,a)

    E-Print Network [OSTI]

    Thermodynamics of finite magnetic two-isomer systems Peter Borrmann, Heinrich Stamerjohanns Carlo simulations to investigate the thermodynamical behavior of aggregates consisting of few thermodynamically the nature of the transition between the ring and the chain ``phase.'' © 1999 American Institute

  16. A multichannel magnetic probe system for analysing magnetic fluctuations in helical axis plasmas

    SciTech Connect (OSTI)

    Haskey, S. R.; Blackwell, B. D.; Seiwald, B.; Hole, M. J.; Pretty, D. G.; Howard, J.; Wach, J. [Plasma Research Laboratory, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)] [Plasma Research Laboratory, Research School of Physical Sciences and Engineering, The Australian National University, Canberra, ACT 0200 (Australia)

    2013-09-15T23:59:59.000Z

    The need to understand the structure of magnetic fluctuations in H-1NF heliac [S. Hamberger et al., Fusion Technol. 17, 123 (1990)] plasmas has motivated the installation of a sixteen former, tri-axis helical magnetic probe Mirnov array (HMA). The new array complements two existing poloidal Mirnov arrays by providing polarisation information, higher frequency response, and improved toroidal resolution. The helical placement is ideal for helical axis plasmas because it positions the array as close as possible to the plasma in regions of varying degrees of favourable curvature in the magnetohydrodynamic sense, but almost constant magnetic angle. This makes phase variation with probe position near linear, greatly simplifying the analysis of the data. Several of the issues involved in the design, installation, data analysis, and calibration of this unique array are presented including probe coil design, frequency response measurements, mode number identification, orientation calculations, and mapping probe coil positions to magnetic coordinates. Details of specially designed digitally programmable pre-amplifiers, which allow gains and filters to be changed as part of the data acquisition initialisation sequence and stored with the probe signals, are also presented. The low shear heliac geometry [R. Jiménez-Gómez et al., Nucl. Fusion 51, 033001 (2011)], flexibility of the H-1NF heliac, and wealth of information provided by the HMA create a unique opportunity for detailed study of Alfvén eigenmodes, which could be a serious issue for future fusion reactors.

  17. Electric dipole moments of nanosolvated acid molecules in water clusters

    E-Print Network [OSTI]

    Guggemos, Nicholas; Kresin, Vitaly V

    2015-01-01T23:59:59.000Z

    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...

  18. Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles

    DOE Patents [OSTI]

    Rote, D.M.; He, Jianliang; Johnson, L.R.

    1992-01-01T23:59:59.000Z

    This report discusses a propulsion and stabilization system comprising a series of figure 8 coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the figure 8 coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension.

  19. Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles

    DOE Patents [OSTI]

    Rote, D.M.; He, J.; Johnson, L.R.

    1994-01-04T23:59:59.000Z

    A propulsion and stabilization system are described comprising a series of coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance, and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension. 8 figures.

  20. Integrated null-flux suspension and multiphase propulsion system for magnetically-levitated vehicles

    DOE Patents [OSTI]

    Rote, Donald M. (Lagrange, IL); He, Jianliang (Woodridge, IL); Johnson, Larry R. (Naperville, IL)

    1994-01-01T23:59:59.000Z

    A propulsion and stabilization system comprising a series of FIG. 8 coils mounted vertically on the walls of the guideway to provide suspension, lateral guidance and propulsion of a magnetically levitated vehicle. This system further allows for altering the magnetic field effects by changing the relative position of the loops comprising the FIG. 8 coils either longitudinally and/or vertically with resulting changes in the propulsion, the vertical stability, and the suspension.

  1. Complete Electric Dipole Response and the Neutron Skin in 208 I. Poltoratska,2

    E-Print Network [OSTI]

    Ponomarev, Vladimir

    of the Witwatersrand, Johannesburg 2050, South Africa 7 Department of Physics, Kyushu University, Fukuoka 812Themba LABS, Somerset West 7129, South Africa 14 ECT*, Villa Tambosi, I-38123, Villazzano (Trento), Italy 15) and spin magnetic dipole (M1) modes in nuclei over a broad excitation energy range to test up

  2. 2 Geomagnetic dipole moment collapse by convective mixing in the core 3 Lijun Liu1

    E-Print Network [OSTI]

    Olson, Peter L.

    through 13 expulsion of mostly poloidal magnetic field by convective 14 upwellings. The dipole fieldkinematic dynamo waves [Gubbins, 1987]. Like resistive 58instabilities, dynamo wave mechanisms are limited on relatively long time scales 61in the outer core. 62[4] Numerical dynamos reveal there are fast, advection- 63

  3. Design and fabrication of a stress-managed Nb3Sn wind and react dipole

    E-Print Network [OSTI]

    Noyes, Patrick Daniel

    2007-09-17T23:59:59.000Z

    A new approach to high-field dipole design is being developed at Texas A&M University. The goal of the development is to facilitate the use of high-field conductors (Nb3 and Bi-2212) and to manage Lorentz stress and magnetization so that field...

  4. The Pygmy Dipole Resonance -history and overview

    E-Print Network [OSTI]

    Zilges, Andreas

    Dipole Resonance (GDR) Phys. Rev. 71 (1947) 3 1947: Photo-Fission in Uranium #12;Giant Dipole Resonance of symmetry energy in EoS A. Carbone et al. PRC 81 (2010) 041301(R) #12;Relevance of PDR · Universal collective excitation mode · Connection to neutron radius, neutron skin · Slope of symmetry energy in EoS

  5. Lithium electric dipole polarizability M. Puchalski

    E-Print Network [OSTI]

    Pachucki, Krzysztof

    Lithium electric dipole polarizability M. Puchalski Faculty of Chemistry, Adam Mickiewicz, 00-681 Warsaw, Poland The electric dipole polarizability of the lithium atom in the ground state phenomena, such as van der Waals interactions in ultra-cold collisions [1­3] and Bose- Einstein condensation

  6. Progress in the Integrated Simulation of Thermal-Hydraulic Operation of the ITER Magnet System

    E-Print Network [OSTI]

    Bagnasco, M; Bessette, D; Marinucci, C

    2010-01-01T23:59:59.000Z

    A new integrated computer code is being developed for the simulations of the overall behavior of the ITER magnet cryo-system. The existing THEA, FLOWER and POWER codes, assembled as modules of a computational environment (Super-Magnet) have been upgraded to perform global simulations of the cooling circuit for the ITER magnet system. The thermal coupling resulting from the generic geometric configurations has been implemented to realize quasi-three-dimensional simulations of the winding pack. In this paper we present details on the model.

  7. Development of a high quality kicker magnet system

    SciTech Connect (OSTI)

    Dinkel, J.; Hanna, B.; Jensen, C.; Qunell, D.; Reilly, R.

    1993-05-01T23:59:59.000Z

    Presently, there are 6 proton and 6 antiproton bunches used for collider operation in the Fermilab Tevatron. As the number of particles in these bunches increases, experimenter`s detectors begin to saturate. To alleviate this situation, protons and antiprotons will be redistributed in 36 bunches instead of 6 to reduce the number of interactions per crossing. In order to carry this out, the rise and fall times of the Tevatron antiproton injection kicker which deflects the antiprotons onto the closed orbit must be reduced to accommodate the increased number of bunches circulating in the machine. To meet these criteria, it is necessary to reduce the inductance per unit length as seen by the driving source in order to achieve the necessary propagation time through the magnet, For a given aperture, this can be readily done using a picture frame design powered with two pulses of opposite polarity. Two magnets are required, each with a magnetic length of 2.41 m.

  8. Magnetic Monopoles in Spin Ice

    E-Print Network [OSTI]

    Claudio Castelnovo; Roderich Moessner; Shivaji L. Sondhi

    2007-10-31T23:59:59.000Z

    Electrically charged particles, such as the electron, are ubiquitous. By contrast, no elementary particles with a net magnetic charge have ever been observed, despite intensive and prolonged searches. We pursue an alternative strategy, namely that of realising them not as elementary but rather as emergent particles, i.e., as manifestations of the correlations present in a strongly interacting many-body system. The most prominent examples of emergent quasiparticles are the ones with fractional electric charge e/3 in quantum Hall physics. Here we show that magnetic monopoles do emerge in a class of exotic magnets known collectively as spin ice: the dipole moment of the underlying electronic degrees of freedom fractionalises into monopoles. This enables us to account for a mysterious phase transition observed experimentally in spin ice in a magnetic field, which is a liquid-gas transition of the magnetic monopoles. These monopoles can also be detected by other means, e.g., in an experiment modelled after the celebrated Stanford magnetic monopole search.

  9. Magnetic Resonant Wireless Power Delivery for Distributed Sensor and Wireless Systems

    E-Print Network [OSTI]

    Cervesato, Iliano

    Magnetic Resonant Wireless Power Delivery for Distributed Sensor and Wireless Systems Brian J. Lee, Pittsburgh, PA 15213 Abstract-- In this paper we report on a resonant wireless power delivery system using to loads distributed in the system. We experimentally map the power distribution for one and multiple loads

  10. Dynamic magnetic susceptibility of systems with long-range magnetic order

    SciTech Connect (OSTI)

    Vannette, Matthew Dano

    2009-05-15T23:59:59.000Z

    The utility of the TDR as an instrument in the study of magnetically ordered materials has been expanded beyond the simple demonstration purposes. Results of static applied magnetic field dependent measurements of the dynamic magnetic susceptibility, ?, of various ferromagnetic (FM) and antiferromagnetic (AFM) materials showing a range of transition temperatures (1-800 K) are presented. Data was collected primarily with a tunnel diode resonator (TDR) at different radio-frequencies ({approx}10-30 MHz). In the vicinity of TC local moment ferromagnets show a very sharp, narrow peak in ? which is suppressed in amplitude and shifted to higher temperatures as the static bias field is increased. Unexpectedly, critical scaling analysis fails for these data. It is seen that these data are frequency dependent, however there is no simple method whereby measurement frequency can be changed in a controllable fashion. In contrast, itinerant ferromagnets show a broad maximum in ? well below TC which is suppressed and shifts to lower temperatures as the dc bias field is increased. The data on itinerant ferromagnets is fitted to a semi-phenomenological model that suggests the sample response is dominated by the uncompensated minority spins in the conduction band. Concluding remarks suggest possible scenarios to achieve frequency resolved data using the TDR as well as other fields in which the apparatus may be exploited.

  11. Microwave probes Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas

    E-Print Network [OSTI]

    R. Celistrino Teixeira; C. Hermann-Avigliano; Thanh Long Nguyen; T. Cantat-Moltrecht; Jean-Michel Raimond; S. Haroche; S. Gleyzes; M. Brune

    2015-02-14T23:59:59.000Z

    We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

  12. Microwave probes Dipole Blockade and van der Waals Forces in a Cold Rydberg Gas

    E-Print Network [OSTI]

    Teixeira, R Celistrino; Nguyen, Thanh Long; Cantat-Moltrecht, T; Raimond, Jean-Michel; Haroche, S; Gleyzes, S; Brune, M

    2015-01-01T23:59:59.000Z

    We show that microwave spectroscopy of a dense Rydberg gas trapped on a superconducting atom chip in the dipole blockade regime reveals directly the dipole-dipole many-body interaction energy spectrum. We use this method to investigate the expansion of the Rydberg cloud under the effect of repulsive van der Waals forces and the breakdown of the frozen gas approximation. This study opens a promising route for quantum simulation of many-body systems and quantum information transport in chains of strongly interacting Rydberg atoms.

  13. Effects and Correction of Closed Orbit Magnet Errors in the SNS Ring

    SciTech Connect (OSTI)

    Bunch, S.C.; Holmes, J.

    2004-01-01T23:59:59.000Z

    We consider the effect and correction of three types of orbit errors in SNS: quadrupole displacement errors, dipole displacement errors, and dipole field errors. Using the ORBIT beam dynamics code, we focus on orbit deflection of a standard pencil beam and on beam losses in a high intensity injection simulation. We study the correction of these orbit errors using the proposed system of 88 (44 horizontal and 44 vertical) ring beam position monitors (BPMs) and 52 (24 horizontal and 28 vertical) dipole corrector magnets. Correction is carried out numerically by adjusting the kick strengths of the dipole corrector magnets to minimize the sum of the squares of the BPM signals for the pencil beam. In addition to using the exact BPM signals as input to the correction algorithm, we also consider the effect of random BPM signal errors. For all three types of error and for perturbations of individual magnets, the correction algorithm always chooses the three-bump method to localize the orbit displacement to the region between the magnet and its adjacent correctors. The values of the BPM signals resulting from specified settings of the dipole corrector kick strengths can be used to set up the orbit response matrix, which can then be applied to the correction in the limit that the signals from the separate errors add linearly. When high intensity calculations are carried out to study beam losses, it is seen that the SNS orbit correction system, even with BPM uncertainties, is sufficient to correct losses to less than 10-4 in nearly all cases, even those for which uncorrected losses constitute a large portion of the beam.

  14. Effective chiral magnetic currents, topological magnetic charges, and microwave vortices in a cavity with an enclosed ferrite disk

    E-Print Network [OSTI]

    Michael Sigalov; E. O. Kamenetskii; Reuven Shavit

    2007-07-09T23:59:59.000Z

    In microwaves, a TE-polarized rectangular-waveguide resonator with an inserted thin ferrite disk gives an example of a nonintegrable system. The interplay of reflection and transmission at the disk interfaces together with the material gyrotropy effect gives rise to whirlpool-like electromagnetic vortices in the proximity of the ferromagnetic resonance. Based on numerical simulation, we show that a character of microwave vortices in a cavity can be analyzed by means of consideration of equivalent magnetic currents. Maxwell equations allows introduction of a magnetic current as a source of the electromagnetic field. Specifically, we found that in such nonintegrable structures, magnetic gyrotropy and geometrical factors leads to the effect of symmetry breaking resulting in effective chiral magnetic currents and topological magnetic charges. As an intriguing fact, one can observe precessing behavior of the electric-dipole polarization inside a ferrite disk.

  15. A nonlinearity in permanent-magnet systems used in watt balances

    E-Print Network [OSTI]

    Li, Shisong; Pratt, Jon

    2014-01-01T23:59:59.000Z

    Watt balances are used to measure the Planck constant and will be used in the future to realize mass at the kilogram level. They increasingly rely on permanent magnet systems to generate the magnetic flux. It has been known that the weighing current might effect the magnetization state of the permanent magnetic system used in these systems causing a systematic bias that can lead to an error in the result if not accounted for. In this article a simple model explaining the effect of the weighing current on the yoke of the magnet is developed. This model leads to a nonlinear dependence of the magnetic flux density in the gap that is proportional to the squared value of the coil current. The effect arises from changing the reluctance of the yoke by the additional field produced by the coil. Our analysis shows that the effect depends on the width of the air gap, the magnetic flux density in the air gap, and the $BH$ curve of the yoke material. Suggestions to reduce the nonlinear effect are discussed.

  16. Steel characteristics measurement system using Barkhausen jump sum rate and magnetic field intensity and method of using same

    DOE Patents [OSTI]

    Kohn, Gabriel (Omer, IL); Hicho, George (Derwood, MD); Swartzendruber, Lydon (New Carrollton, MD)

    1997-01-01T23:59:59.000Z

    A steel hardness measurement system and method of using same are provided for measuring at least one mechanical or magnetic characteristic of a ferromagnetic sample as a function of at least one magnetic characteristic of the sample. A magnetic field generator subjects the sample to a variable external magnetic field. The magnetic field intensity of the magnetic field generated by the magnetic field generating means is measured and a signal sensor is provided for measuring Barkhausen signals from the sample when the sample is subjected to the external magnetic field. A signal processing unit calculates a jump sum rate first moment as a function of the Barkhausen signals measured by the signal sensor and the magnetic field intensity, and for determining the at least one mechanical or magnetic characteristic as a function of the jump sum rate first moment.

  17. Steel characteristics measurement system using Barkhausen jump sum rate and magnetic field intensity and method of using same

    DOE Patents [OSTI]

    Kohn, G.; Hicho, G.; Swartzendruber, L.

    1997-04-08T23:59:59.000Z

    A steel hardness measurement system and method of using same are provided for measuring at least one mechanical or magnetic characteristic of a ferromagnetic sample as a function of at least one magnetic characteristic of the sample. A magnetic field generator subjects the sample to a variable external magnetic field. The magnetic field intensity of the magnetic field generated by the magnetic field generating means is measured and a signal sensor is provided for measuring Barkhausen signals from the sample when the sample is subjected to the external magnetic field. A signal processing unit calculates a jump sum rate first moment as a function of the Barkhausen signals measured by the signal sensor and the magnetic field intensity, and for determining the at least one mechanical or magnetic characteristic as a function of the jump sum rate first moment. 7 figs.

  18. Brookhaven National Laboratory Superconducting Magnet Division

    E-Print Network [OSTI]

    Ohta, Shigemi

    cold bore tube and the ID of the magnet coils than the RHIC arc dipoles. This will reduce the flow. Muratore TEST PROCEDURE FOR THE RETEST OF D1L101 (LHC SINGLE APERTURE DIPOLE)IN HORIZONTAL TEST BAY E RUN testing in Horizontal Test Bay C. The test history (quench currents, number of cooldowns, etc

  19. Dipole gravity waves from unbound quadrupoles

    E-Print Network [OSTI]

    Felber, Franklin

    2010-01-01T23:59:59.000Z

    Dipole gravitational disturbances from gravitationally unbound mass quadrupoles propagate to the radiation zone with signal strength at least of quadrupole order if the quadrupoles are nonrelativistic, and of dipole order if relativistic. Angular distributions of parallel-polarized and transverse-polarized dipole power in the radiation zone are calculated for simple unbound quadrupoles, like a linear-oscillator/stress-wave pair and a particle storage ring. Laboratory tests of general relativity through measurements of dipole gravity waves in the source region are proposed. A NASA G2 flywheel module with a modified rotor can produce a post-Newtonian dc bias signal at a gradiometer up to 1 mE. At peak luminosity, the repulsive dipole impulses of proton bunches at the LHC can produce an rms velocity of a high-Q detector surface up to 4 micron/s. Far outside the source region, Newtonian lunar dipole gravity waves can produce a 1-cm displacement signal at LISA. Dipole signal strengths of astrophysical events invol...

  20. Dipole gravity waves from unbound quadrupoles

    E-Print Network [OSTI]

    Franklin Felber

    2010-06-10T23:59:59.000Z

    Dipole gravitational disturbances from gravitationally unbound mass quadrupoles propagate to the radiation zone with signal strength at least of quadrupole order if the quadrupoles are nonrelativistic, and of dipole order if relativistic. Angular distributions of parallel-polarized and transverse-polarized dipole power in the radiation zone are calculated for simple unbound quadrupoles, like a linear-oscillator/stress-wave pair and a particle storage ring. Laboratory tests of general relativity through measurements of dipole gravity waves in the source region are proposed. A NASA G2 flywheel module with a modified rotor can produce a post-Newtonian dc bias signal at a gradiometer up to 1 mE. At peak luminosity, the repulsive dipole impulses of proton bunches at the LHC can produce an rms velocity of a high-Q detector surface up to 4 micron/s. Far outside the source region, Newtonian lunar dipole gravity waves can produce a 1-cm displacement signal at LISA. Dipole signal strengths of astrophysical events involving unbound quadrupoles, like near collisions and neutron star kicks in core-collapse supernovae, are estimated.

  1. Superconducting magnetic energy storage apparatus structural support system

    DOE Patents [OSTI]

    Withers, Gregory J. (Bolingbrook, IL); Meier, Stephen W. (Bolingbrook, IL); Walter, Robert J. (Batavia, IL); Child, Michael D. (Naperville, IL); DeGraaf, Douglas W. (Downers Grove, IL)

    1992-01-01T23:59:59.000Z

    A superconducting magnetic energy storage apparatus comprising a cylindrical superconducting coil; a cylindrical coil containment vessel enclosing the coil and adapted to hold a liquid, such as liquefied helium; and a cylindrical vacuum vessel enclosing the coil containment vessel and located in a restraining structure having inner and outer circumferential walls and a floor; the apparatus being provided with horizontal compression members between (1) the coil and the coil containment vessel and (2) between the coil containment vessel and the vacuum vessel, compression bearing members between the vacuum vessel and the restraining structure inner and outer walls, vertical support members (1) between the coil bottom and the coil containment vessel bottom and (2) between the coil containment vessel bottom and the vacuum vessel bottom, and external supports between the vacuum vessel bottom and the restraining structure floor, whereby the loads developed by thermal and magnetic energy changes in the apparatus can be accommodated and the structural integrity of the apparatus be maintained.

  2. Magnetohydrodynamics wave propagation in the neighbourhood of two dipoles

    E-Print Network [OSTI]

    J. A. McLaughlin; A. W. Hood

    2007-12-11T23:59:59.000Z

    This paper is the third in a series of investigations by the authors. The nature of fast magnetoacoustic and Alfv\\'en waves is investigated in a 2D $\\beta=0$ plasma in the neighbourhood of two dipoles. We use both numerical simulations (two-step Lax-Wendroff scheme) and analytical techniques (WKB approximation). It is found that the propagation of the linear fast wave is dictated by the Alfv\\'en speed profile and that close to the null, the wave is attracted to the neutral point. However, it is also found that in this magnetic configuration some of the wave can escape the refraction effect; this had not been seen in previous investigations by the authors. The wave split occurs near the regions of very high Alfv\\'en speed (found near the loci of the two dipoles). Also, for the set-up investigated it was found that 40% of the wave energy accumulates at the null. Ohmic dissipation will then extract the wave energy at this point. The Alfv\\'en wave behaves in a different manner in that part of the wave accumulates along the separatrices and part escapes. Hence, the current density will accumulate at this part of the topology and this is where wave heating will occur. The phenomenon of wave accumulation at a specific place is a feature of both wave types, as is the result that a fraction of the wave can now escape the numerical box when propagating in this magnetic configuration.

  3. Circuitry, systems and methods for detecting magnetic fields

    DOE Patents [OSTI]

    Kotter, Dale K. (Shelley, ID) [Shelley, ID; Spencer, David F. (Idaho Falls, ID) [Idaho Falls, ID; Roybal, Lyle G. (Idaho Falls, ID) [Idaho Falls, ID; Rohrbaugh, David T. (Idaho Falls, ID) [Idaho Falls, ID

    2010-09-14T23:59:59.000Z

    Circuitry for detecting magnetic fields includes a first magnetoresistive sensor and a second magnetoresistive sensor configured to form a gradiometer. The circuitry includes a digital signal processor and a first feedback loop coupled between the first magnetoresistive sensor and the digital signal processor. A second feedback loop which is discrete from the first feedback loop is coupled between the second magnetoresistive sensor and the digital signal processor.

  4. QED vacuum fluctuations and induced electric dipole moment of the neutron

    SciTech Connect (OSTI)

    Dominguez, C. A. [Centre for Theoretical Physics and Astrophysics, University of Cape Town, Rondebosch 7700 (South Africa); Department of Physics, Stellenbosch University, Stellenbosch 7600 (South Africa); Falomir, H. [Instituto de Fisica La Plata-Consejo Nacional de Ciencia y Tecnica, Universidad Nacional de La Plata (Argentina); Ipinza, M.; Loewe, M. [Facultad de Fisica, Pontificia Universidad Catolica de Chile, Casilla 306, Santiago 22 (Chile); Kohler, S. [Department of Physics, Stellenbosch University, Stellenbosch 7600 (South Africa); Rojas, J. C. [Departamento de Fisica, Universidad Catolica del Norte, Casilla 1280, Antofagasta (Chile)

    2009-08-01T23:59:59.000Z

    Quantum fluctuations in the QED vacuum generate nonlinear effects, such as peculiar induced electromagnetic fields. In particular, we show here that an electrically neutral particle, possessing a magnetic dipole moment, develops an induced electric dipole-type moment with unusual angular dependence, when immersed in a quasistatic, constant external electric field. The calculation of this effect is done in the framework of the Euler-Heisenberg effective QED Lagrangian, corresponding to the weak field asymptotic expansion of the effective action to one-loop order. It is argued that the neutron might be a good candidate to probe this signal of nonlinearity in QED.

  5. Magnets for Muon 6D Cooling Channels

    SciTech Connect (OSTI)

    Johnson, Rolland [Muons, Inc.; Flanagan, Gene [Muons, Inc.

    2014-09-10T23:59:59.000Z

    The Helical Cooling Channel (HCC), an innovative technique for six-dimensional (6D) cooling of muon beams using a continuous absorber inside superconducting magnets, has shown considerable promise based on analytic and simulation studies. The implementation of this revolutionary method of muon cooling requires high field superconducting magnets that provide superimposed solenoid, helical dipole, and helical quadrupole fields. Novel magnet design concepts are required to provide HCC magnet systems with the desired fields for 6D muon beam cooling. New designs feature simple coil configurations that produce these complex fields with the required characteristics, where new high field conductor materials are particularly advantageous. The object of the program was to develop designs and construction methods for HCC magnets and design a magnet system for a 6D muon beam cooling channel. If successful the program would develop the magnet technologies needed to create bright muon beams for many applications ranging from scientific accelerators and storage rings to beams to study material properties and new sources of energy. Examples of these applications include energy frontier muon colliders, Higgs and neutrino factories, stopping muon beams for studies of rare fundamental interactions and muon catalyzed fusion, and muon sources for cargo screening for homeland security.

  6. A 64-channel personal computer based image reconstruction system and applications in single echo acquisition magnetic resonance elastography and ultra-fast magnetic resonance imaging.

    E-Print Network [OSTI]

    Yallapragada, Naresh

    2009-05-15T23:59:59.000Z

    , this value is 2? x 42.5759 MHz/Tesla. This translates to a Larmor frequency of 200.238 MHz for the 4.7T magnet situated in the Magnetic Resonance Systems Lab (MRSL). In the presence of the static ????the proton population aligns itself according...

  7. Plant and operational features of the BPA 30 MJ superconducting magnetic energy storage system

    SciTech Connect (OSTI)

    Rogers, J.D.; Hauer, J.F.

    1984-01-01T23:59:59.000Z

    A 30 MJ superconducting magnetic energy storage (SMES) system was designed and developed for application in the Western US Power System to damp power oscillations that limit high voltage ac transmission. The system is in place at the Bonneville Power Administration (BPA) Tacoma Substation and has been in an experimental use for over a year. Extended operations of the unit have been undertaken with success. The physical, electrical, and operational features of the SMES system are given.

  8. A Coupled Polarization-Matrix Inversion and Iteration Approach for Accelerating the Dipole Convergence in a Polarizable Potential Function

    E-Print Network [OSTI]

    Minnesota, University of

    approach is more efficient computationally for large systems in molecular dynamics simulations on the instantaneous electric field from the permanent charges and induced dipoles of the rest of the system.2

  9. Fiber-Optic Stethoscope: A Cardiac Monitoring and Gating System for Magnetic Resonance Microscopy

    E-Print Network [OSTI]

    Fiber-Optic Stethoscope: A Cardiac Monitoring and Gating System for Magnetic Resonance Microscopy monitoring and gating purposes. The fiber-optic stethoscope system offers a novel approach to measuring cardiac activity that, unlike the ECG, is immune to electromagnetic effects. The fiber-optic stethoscope

  10. CONTROL SYSTEM FOR MAGNET POWER SUPPLIES FOR NOVOSIBIRSK FREE ELECTRON LASER

    E-Print Network [OSTI]

    Kozak, Victor R.

    CONTROL SYSTEM FOR MAGNET POWER SUPPLIES FOR NOVOSIBIRSK FREE ELECTRON LASER Yu.M.Velikanov, V, the software tools for power supply diagnostics are described. INTRODUCTION A high-power free electron laser electron laser (FEL) is described. The characteristics and structure of the power supply system

  11. Optically Detected Magnetic Resonance Studies on ?-conjugated semiconductor systems

    SciTech Connect (OSTI)

    Chen, Ying

    2011-12-06T23:59:59.000Z

    Optically Detected Magnetic Resonance (ODMR) techniques were used to investigate the dynamics of excitons and charge carriers in ?-conjugated organic semiconductors. Degradation behavior of the negative spin-1/2 electroluminescence-detected magnetic resonance (ELDMR) was observed in Alq3 devices. The increase in the resonance amplitude implies an increasing bipolaron formation during degradation, which might be the result of growth of charge traps in the device. The same behavior of the negative spin-1/2 ELDMR was observed in 2wt% Rubrene doped Tris(8-hydroxyquinolinato)aluminium (Alq3) devices. However, with increasing injection current, a positive spin-1/2 ELDMR, together with positive spin 1 triplet powder patterns at {delta}m{sub S}={+-}1 and {delta}m{sub S}={+-}2, emerges. Due to the similarities in the frequency dependences of single and double modulated ELDMR and the photoluminescence-detected magnetic resonance (PLDMR) results in poly[2-methoxy-5-(2 -ethyl-hexyloxy)-1,4-phenyl ene vinylene] (MEH-PPV) films, the mechanism for this positive spin-1/2 ELDMR was assigned to enhanced triplet-polaron quenching under resonance conditions. The ELDMR in rubrene doped Alq3 devices provides a path to investigate charge distribution in the device under operational conditions. Combining the results of several devices with different carrier blocking properties and the results from transient EL, it was concluded trions not only exist near buffer layer but also exist in the electron transport layer. This TPQ model can also be used to explain the positive spin-1/2 PLDMR in poly(3-hexylthiophene) (P3HT) films at low temperature and in MEH-PPV films at various temperatures up to room temperature. Through quantitative analysis, TE-polaron quenching (TPQ) model is shown having the ability to explain most behaviors of the positive spin-1/2 resonance. Photocurrent detected magnetic resonance (PCDMR) studies on MEH-PPV devices revealed a novel transient resonance signal. The signal may originate from the higher concentration of deep traps near cathode. A quantitative analysis based on this assumption was carried out and found to be consistent with the experimental results.

  12. Experience with operation of a large magnet system in the international fusion superconducting magnet test facility

    SciTech Connect (OSTI)

    Fietz, W.A.; Ellis, J.F.; Haubenreich, P.N.; Schwenterly, S.W.; Stamps, R.E.

    1985-01-01T23:59:59.000Z

    Superconducting toroidal field systems, including coils and ancillaries, are being developed through international collaboration in the Large Coil Task. Focal point is a test facility in Oak Ridge where six coils will be tested in a toroidal array. Shakedown of the facility and preliminary tests of the first three coils (from Japan, Switzerland, and the US) were accomplished in 1984. Useful data were obtained on performance of the helium refrigerator and distribution system, power supplies, control and data acquisition systems and voltages, currents, strains, and acoustic emission in the coils. Performance was generally gratifying except for the helium system, where improvements are being made.

  13. Infinite volume limit for the dipole gas

    E-Print Network [OSTI]

    J. Dimock

    2009-04-28T23:59:59.000Z

    We consider a classical dipole gas in with low activity and show that the pressure has a limit as the volume goes to infinity. The result is obtained by a renormalization group analysis of the model.

  14. Earth Planets Space, 52, 329336, 2000 Rock magnetism of sediments in the Angola-Namibia upwelling system

    E-Print Network [OSTI]

    Yamazaki, Toshitsugu

    Earth Planets Space, 52, 329­336, 2000 Rock magnetism of sediments in the Angola-Namibia upwelling system with special reference to loss of magnetization after core recovery Toshitsugu Yamazaki1 , Peter A Magnetism, University of Minnesota, Minneapolis, MN 55455-0128, U.S.A. 3Hawaii Institute of Geophysics

  15. AN UPGRADE OF MAGNET-FIELD-DRIVEN TIMING SYSTEMS AT THE AGS.

    SciTech Connect (OSTI)

    TIAN, Y.; OERTER, B.

    2005-10-10T23:59:59.000Z

    An upgrade of the main magnet-field-driven timing systems at Brookhaven National Laboratory's Alternating Gradient Synchrotron (AGS) and Booster accelerators will be described in this paper. A novel approach using content addressable memory (CAM) is applied to overcome a weakness in the previous systems, which required a reproducible dwell field for proper operation. Upgraded from a multibus-based system to a VME-based system, the new timing system also proves easier to maintain and to diagnose. Details of the system architecture, as well as its application in other timing systems will be discussed.

  16. Magnetic moment versus tensor charge

    E-Print Network [OSTI]

    M. Mekhfi

    2005-05-10T23:59:59.000Z

    We express the baryon magnetic moments in terms of the baryon tensor charges, considering the quarks as relativistic interacting objects. Once tensor charges get measured accurately, the formula for the baryon magnetic moment will serve to extract precise information on the quark anomalous magnetic moment, the quark effective mass and the ratio of the quark constituent mass to the quark effective mass. The analogous formula for the baryon electric dipole moment is of no great use as it gets eventually sizable contributions from various CP- violating sources not necessary associated to the quark electric dipole moment.

  17. Dipole Bands in {sup 196}Hg

    SciTech Connect (OSTI)

    Lawrie, J. J.; Lawrie, E. A.; Newman, R. T.; Sharpey-Schafer, J. F.; Smit, F. D. [iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Msezane, B. [iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Physics Department, University of Zululand, Private Bag X1001, Kwadlangezwa 3886 (South Africa); Benatar, M.; Mabala, G. K.; Mutshena, K. P. [iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Physics Department, University of Cape Town, Rondebosch 7700 (South Africa); Federke, M.; Mullins, S. M. [Physics Department, University of Cape Town, Rondebosch 7700 (South Africa); Ncapayi, N. J.; Vymers, P. [iThemba LABS, PO Box 722, Somerset West 7129 (South Africa); Physics Department, University of the Western Cape, Private Bag X17, Belleville 7535 (South Africa)

    2011-10-28T23:59:59.000Z

    High spin states in {sup 196}Hg have been populated in the {sup 198}Pt({alpha},6n) reaction at 65 MeV and the level scheme has been extended. A new dipole band has been observed and a previously observed dipole has been confirmed. Excitation energies, spins and parities of these bands were determined from DCO ratio and linear polarization measurements. Possible quasiparticle excitations responsible for these structures are discussed.

  18. atlas magnet system: Topics by E-print Network

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

    all ATLAS sub-detectors by using a system of >130 server machines running the industrial SCADA product PVSS. This highly distributed system reads, processes and archives of the...

  19. HIGH-POWER PRECISION CURRENT SUPPLY IST2-1000M FOR ELEMENTS OF MAGNETIC SYSTEMS OF ACCELERATORS AND

    E-Print Network [OSTI]

    Kozak, Victor R.

    HIGH-POWER PRECISION CURRENT SUPPLY IST2-1000M FOR ELEMENTS OF MAGNETIC SYSTEMS OF ACCELERATORS. These supplies are intended to power magnetic systems of accelerators, requiring high stability and low ripples current at non-inductive load % 0,02 Rate of current raise without disturbing operation of the system

  20. Magnetic levitation systems for future aeronautics and space research and missions

    SciTech Connect (OSTI)

    Blankson, I.M.; Mankins, J.C.

    1996-02-01T23:59:59.000Z

    The objectives, advantages, and research needs for several applications of superconducting magnetic levitation to aerodynamics research, testing, and space-launch are discussed. Applications include very large-scale magnetic balance and suspension systems for high alpha testing, support interference-free testing of slender hypersonic propulsion/airframe integrated vehicles, and hypersonic maglev. Current practice and concepts are outlined as part of a unified effort in high magnetic fields R&D within NASA. Recent advances in the design and construction of the proposed ground-based Holloman test track (rocket sled) that uses magnetic levitation are presented. It is projected that ground speeds of up to Mach 8 to 11 at sea-level are possible with such a system. This capability may enable supersonic combustor tests as well as ramjet-to-scramjet transition simulation to be performed in clean air. Finally a novel space launch concept (Maglifter) which uses magnetic levitation and propulsion for a re-usable `first stage` and rocket or air-breathing combined-cycle propulsion for its second stage is discussed in detail. Performance of this concept is compared with conventional advanced launch systems and a preliminary concept for a subscale system demonstration is presented.

  1. Systems and methods for creation of conducting networks of magnetic particles through dynamic self-assembly process

    DOE Patents [OSTI]

    Snezhko, Oleksiy (Woodridge, IL); Aronson, Igor (Darien, IL); Kwok, Wai-Kwong (Downers Grove, IL)

    2011-01-25T23:59:59.000Z

    Self-assembly of magnetic microparticles in AC magnetic fields. Excitation of the system by an AC magnetic field provides a variety of patterns that can be controlled by adjusting the frequency and the amplitude of the field. At low particle densities the low-frequency magnetic excitation favors cluster phase formation, while high frequency excitation favors chains and netlike structures. For denser configurations, an abrupt transition to the network phase was obtained.

  2. Wilson-'t Hooft loops in finite-temperature noncommutative dipole field theory from dual supergravity

    SciTech Connect (OSTI)

    Huang, W.-H. [Department of Physics, National Cheng Kung University, Tainan, Taiwan (China)

    2007-11-15T23:59:59.000Z

    We first study the temporal Wilson loop in the finite-temperature noncommutative dipole field theory from the string/gauge correspondence. The associated dual supergravity background is constructed from the near-horizon geometry of near-extremal D branes, after applying T duality and smeared twist. We investigate the string configuration therein and find that while the temperature produces a maximum distance L{sub max} in the interquark distance the dipole in there could produce a minimum distance L{sub min}. The quark boundary pair therefore could be found only if their distance is between L{sub min} and L{sub max}. We also show that, beyond a critical temperature the quark pair becomes totally free due to screening by thermal bath. We next study the spatial Wilson loop and find the confining nature in the zero temperature 3D and 4D nonsupersymmetry dipole gauge theory. The string tension of the linear confinement potential is obtained and found to be a decreasing function of the dipole field. We also investigate the associated t'Hooft loop and determine the corresponding monopole antimonopole potential. The conventional screening of magnetic charge which indicates the confinement of the electric charge is replaced by a strong repulsive however. Finally, we show that the dual string which is rotating along the dipole deformed S{sup 5} will behave as a static one without dipole field, which has no minimum distance and has larger energy than a static one with dipole field. We discuss the phase transition between these string solutions.

  3. MAGNETIC FIELD STRUCTURE IN A HIGH-MASS OUTFLOW/DISK SYSTEM

    SciTech Connect (OSTI)

    Beuther, H. [Max-Planck-Institute for Astronomy, Koenigstuhl 17, 69117 Heidelberg (Germany); Vlemmings, W. H. T. [Argelander Institute for Astronomy, University of Bonn, Auf dem Huegel 71, 53121 Bonn (Germany); Rao, R. [Academia Sinica, Institute of Astronomy and Astrophysics, Taipei, Taiwan (China); Van der Tak, F. F. S., E-mail: beuther@mpia.d, E-mail: wouter@astro.uni-bonn.d, E-mail: rrao@sma.hawaii.ed, E-mail: vdtak@sron.n [SRON Netherlands Institute for Space Research, Landleven 12, 9747 AD Groningen (Netherlands)

    2010-11-20T23:59:59.000Z

    To characterize the magnetic field structure of the outflow and core region within a prototypical high-mass star-forming region, we analyzed polarized CO(3-2)-for the first time observed with the Submillimeter Array-as well as 880 {mu}m submillimeter continuum emission from the high-mass outflow/disk system IRAS 18089-1732. Both emission features with polarization degrees at a few percent level indicate that the magnetic field structure is largely aligned with the outflow/jet orientation from small core scales to larger outflow scales. Although quantitative estimates are crude, the analysis indicates that turbulent energy dominates over magnetic energy. The data also suggest a magnetic field strength increase from the lower-density envelope to the higher-density core.

  4. Cost Effective Open Geometry HTS MRI System amended to BSCCO 2212 Wire for High Field Magnets

    SciTech Connect (OSTI)

    Kennth Marken

    2006-08-11T23:59:59.000Z

    The original goal of this Phase II Superconductivity Partnership Initiative project was to build and operate a prototype Magnetic Resonance Imaging (MRI) system using high temperature superconductor (HTS) coils wound from continuously processed dip-coated BSCCO 2212 tape conductor. Using dip-coated tape, the plan was for MRI magnet coils to be wound to fit an established commercial open geometry, 0.2 Tesla permanent magnet system. New electronics and imaging software for a prototype higher field superconducting system would have added significantly to the cost. However, the use of the 0.2 T platform would allow the technical feasibility and the cost issues for HTS systems to be fully established. Also it would establish the energy efficiency and savings of HTS open MRI compared with resistive and permanent magnet systems. The commercial goal was an open geometry HTS MRI running at 0.5 T and 20 K. This low field open magnet was using resistive normal metal conductor and its heat loss was rather high around 15 kolwatts. It was expected that an HTS magnet would dissipate around 1 watt, significantly reduce power consumption. The SPI team assembled to achieve this goal was led by Oxford Instruments, Superconducting Technology (OST), who developed the method of producing commercial dip coated tape. Superconductive Components Inc. (SCI), a leading US supplier of HTS powders, supported the conductor optimization through powder optimization, scaling, and cost reduction. Oxford Magnet Technology (OMT), a joint venture between Oxford Instruments and Siemens and the world’s leading supplier of MRI magnet systems, was involved to design and build the HTS MRI magnet and cryogenics. Siemens Magnetic Resonance Division, a leading developer and supplier of complete MRI imaging systems, was expected to integrate the final system and perform imaging trials. The original MRI demonstration project was ended in July 2004 by mutual consent of Oxford Instruments and Siemens. Between the project start and that date a substantial shift in the MRI marketplace occurred, with rapid growth for systems at higher fields (1.5 T and above) and a consequent decline in the low field market (<1.0 T). While the project aim appeared technically attainable at that time, the conclusion was reached that the system and market economics do not warrant additional investment. The program was redirected to develop BSCCO 2212 multifilament wire development for high field superconducting magnets for NMR and other scientific research upon an agreement between DOE and Oxford Instruments, Superconducting Technology. The work t took place between September, 2004 and the project end in early 2006 was focused on 2212 multifilamentary wire. This report summarizes the technical achievements both in 2212 dip coated for an HTS MRI system and in BSCCO 2212 multifilamentary wire for high field magnets.

  5. Spectrum of the radiation from electric charges and from dipoles which free infall into a black hole

    E-Print Network [OSTI]

    A. A. Shatskiy; I. D. Novikov; L. N. Lipatova

    2013-03-30T23:59:59.000Z

    The free fall of electric charges and dipoles, radial and freely falling into the Schwarzschild black hole event horizon, was considered. Inverse effect of electromagnetic fields on the black hole is neglected. Dipole was considered as a point particle, so the deformation associated with exposure by tidal forces are neglected. According to the theorem, "the lack of hair" of black holes, multipole magnetic fields must be fully emitted by multipole fall into a black hole. The spectrum of electromagnetic radiation power for these multipoles (monopole and dipole) was found. Differences were found in the spectra for different orientations of the falling dipole. A general method has been developed to find radiated electromagnetic multipole fields for the free falling multipoles into a black hole (including higher order multipoles - quadrupoles, etc.). The electromagnetic spectrum can be compared with observational data from stellar mass and smaller black holes.

  6. A search for the electric dipole of the electron

    SciTech Connect (OSTI)

    Abdullah, K.F.

    1989-08-01T23:59:59.000Z

    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.

  7. Magnetic Levitation System The following figure shows the cross section of a magnetic levitation (MAGLEV) train.

    E-Print Network [OSTI]

    Hagan, Martin

    , step. (With sisotool you can adjust the controller and watch the step response change in real time.) Demonstrate the system step response. Discuss your design steps and the reasons for your final design. Your designs, 3) step response plots for the final design and other potential designs. This project should

  8. Magnetic switching behaviors of orbital states with different magnetic quantum numbers in Au/Fe/MgO multilayer system

    SciTech Connect (OSTI)

    Suzuki, Kosuke, E-mail: kosuzuki@gunma-u.ac.jp; Takubo, Shota; Kato, Tadashi; Yamazoe, Masatoshi; Hoshi, Kazushi; Sakurai, Hiroshi [Department of Electronics and Informatics, Gunma University, 1-5-1 Tenjin-cho, Kiryu, Gunma 376-8515 (Japan); Homma, Yoshiya [International Research Center for Nuclear Materials Science, Institute for Materials Research, Tohoku University, 2145-2 Narita-cho, Oarai-machi, Higashiibaraki-gun, Ibaraki 311-1313 (Japan); Itou, Masayoshi; Sakurai, Yoshiharu [Japan Synchrotron Radiation Research Institute, SPring-8, 1-1-1 Koto, Sayo-cho, Sayo-gun, Hyogo 679-5198 (Japan)

    2014-08-18T23:59:59.000Z

    A spin specific magnetic hysteresis (SSMH) curve and an orbital specific magnetic hysteresis (OSMH) curve are obtained for Fe/Au/Fe/MgO multilayers by magnetic Compton scattering and SQUID magnetometer measurements. The SSMH curve with each contribution of magnetic quantum number |m|?=?0, 1, and 2 states is obtained by decomposition analyses of magnetic Compton profiles. Residual magnetization is observed for the SSMH curve with magnetic quantum number |m|?=?0, 2 and the OSMH curve. Although the SQUID magnetometer measurements do not show perpendicular magnetic anisotropy (PMA) in the present Fe/Au/Fe/MgO multilayer film, the SSMH curve with magnetic quantum number |m|?=?0, 2 and OSMH curve show switching behaviors of PMA.

  9. Systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators

    DOE Patents [OSTI]

    Grisham, Larry R

    2013-12-17T23:59:59.000Z

    The present invention provides systems and methods for the magnetic insulation of accelerator electrodes in electrostatic accelerators. Advantageously, the systems and methods of the present invention improve the practically obtainable performance of these electrostatic accelerators by addressing, among other things, voltage holding problems and conditioning issues. The problems and issues are addressed by flowing electric currents along these accelerator electrodes to produce magnetic fields that envelope the accelerator electrodes and their support structures, so as to prevent very low energy electrons from leaving the surfaces of the accelerator electrodes and subsequently picking up energy from the surrounding electric field. In various applications, this magnetic insulation must only produce modest gains in voltage holding capability to represent a significant achievement.

  10. Design of a magnetic shielding system for the time of flight enhanced diagnostics neutron spectrometer at Experimental Advanced Superconducting Tokamak

    SciTech Connect (OSTI)

    Cui, Z. Q.; Chen, Z. J.; Xie, X. F.; Peng, X. Y.; Hu, Z. M.; Du, T. F.; Ge, L. J.; Zhang, X.; Yuan, X.; Fan, T. S.; Chen, J. X.; Li, X. Q., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn; Zhang, G. H., E-mail: lixq2002@pku.edu.cn, E-mail: guohuizhang@pku.edu.cn [School of Physics, State Key Lab of Nuclear Physics and Technology, Peking University, Beijing 100871 (China); Xia, Z. W. [Southwestern Institute of Physics, Chengdu 610225 (China); Hu, L. Q.; Zhong, G. Q.; Lin, S. Y.; Wan, B. N. [Institute of Plasma Physics, CAS, Hefei 230031 (China)

    2014-11-15T23:59:59.000Z

    The novel neutron spectrometer TOFED (Time of Flight Enhanced Diagnostics), comprising 90 individual photomultiplier tubes coupled with 85 plastic scintillation detectors through light guides, has been constructed and installed at Experimental Advanced Superconducting Tokamak. A dedicated magnetic shielding system has been constructed for TOFED, and is designed to guarantee the normal operation of photomultiplier tubes in the stray magnetic field leaking from the tokamak device. Experimental measurements and numerical simulations carried out employing the finite element method are combined to optimize the design of the magnetic shielding system. The system allows detectors to work properly in an external magnetic field of 200 G.

  11. Magnetic monopole and the nature of the static magnetic field

    E-Print Network [OSTI]

    Xiuqing Huang

    2008-12-10T23:59:59.000Z

    We investigate the factuality of the hypothetical magnetic monopole and the nature of the static magnetic field. It is shown from many aspects that the concept of the massive magnetic monopoles clearly is physically untrue. We argue that the static magnetic field of a bar magnet, in fact, is the static electric field of the periodically quasi-one-dimensional electric-dipole superlattice, which can be well established in some transition metals with the localized d-electron. This research may shed light on the perfect unification of magnetic and electrical phenomena.

  12. Dipole-dipole broadening of Rb ns-np microwave transitions

    SciTech Connect (OSTI)

    Park, Hyunwook; Tanner, P. J.; Claessens, B. J.; Shuman, E. S.; Gallagher, T. F. [Department of Physics, University of Virginia, Charlottesville, Virginia 22904-0714 (United States)

    2011-08-15T23:59:59.000Z

    The dipole-dipole broadening of ns-np microwave transitions of cold Rb Rydberg atoms in a magneto-optical trap has been recorded for 28{<=}n{<=}51. Since the electric dipole transition matrix elements scale as n{sup 2}, a broadening rate scaling as n{sup 4} is expected and a broadening rate of 8.2x10{sup -15}n{sup 4} MHz cm{sup 3} is observed. The observed broadening is smaller than expected from a classical picture due to the spin-orbit interaction in the np atoms. The broadened resonances are asymmetric and cusp shaped, and their line shapes can be reproduced by a diatomic model which takes into account the dipole-dipole interaction, including the spin-orbit interaction, the strengths of the allowed microwave transitions, and the distribution of the atomic spacings in the trap.

  13. LFV decays and anomalous magnetic (electric) moments in a lepton mass matrices ansatz induced by SUSY GUT

    E-Print Network [OSTI]

    W. J. Huo

    2003-01-27T23:59:59.000Z

    By using the anomalous magnetic and electric dipole moments of the $\\tau$ lepton in an effective lagrangian approach to the new physics, we investigate the lepton flavor violation (LFV) decays, $l\\to l'\\gamma$, and $\\mu,\\tau$ anomalous magnetic and electric dipole moments in a lepton mass matrices ansatz which induced by SUSY GUT. We put very stringent constraints LFV decays and $\\tau$ anomalous magnetic and electric dipole moments.

  14. Presented at the Applied Superconductivity Conference, Houston, TX August 4-9, 2002 1 Superconducting Magnets for the `International

    E-Print Network [OSTI]

    Ohta, Shigemi

    ) · the High Energy Storage Ring (HESR) Index Terms--Antiproton beams, fast-ramped superconduct- ing to develop dipole magnets with maximum fields of 2 and 4 Tesla and dipole ramp rates of 4 T/s and 1 T). This magnet has been operated at 4 T/s up to a field of 2 Tesla. Reduced losses and im- proved magnetic field

  15. Dependence of exchange coupling interaction on micromagnetic constants in hard/soft magnetic bilayer systems

    E-Print Network [OSTI]

    Rubloff, Gary W.

    Dependence of exchange coupling interaction on micromagnetic constants in hard/soft magnetic bilayer systems A. J. Zambano,1, * H. Oguchi,1 I. Takeuchi,1 Y. Choi,2,3 J. S. Jiang,2 J. P. Liu,3 S. E December 2006; published 30 April 2007 To elucidate the dependence of exchange coupling behavior of hard/soft

  16. A fast continuous magnetic field measurement system based on digital signal processors

    SciTech Connect (OSTI)

    Velev, G.V.; Carcagno, R.; DiMarco, J.; Kotelnikov, S.; Lamm, M.; Makulski, A.; /Fermilab; Maroussov, V.; /Purdue U.; Nehring, R.; Nogiec, J.; Orris, D.; /Fermilab; Poukhov,; Prakoshyn, F.; /Dubna, JINR; Schlabach, P.; Tompkins, J.C.; /Fermilab

    2005-09-01T23:59:59.000Z

    In order to study dynamic effects in accelerator magnets, such as the decay of the magnetic field during the dwell at injection and the rapid so-called ''snapback'' during the first few seconds of the resumption of the energy ramp, a fast continuous harmonics measurement system was required. A new magnetic field measurement system, based on the use of digital signal processors (DSP) and Analog to Digital (A/D) converters, was developed and prototyped at Fermilab. This system uses Pentek 6102 16 bit A/D converters and the Pentek 4288 DSP board with the SHARC ADSP-2106 family digital signal processor. It was designed to acquire multiple channels of data with a wide dynamic range of input signals, which are typically generated by a rotating coil probe. Data acquisition is performed under a RTOS, whereas processing and visualization are performed under a host computer. Firmware code was developed for the DSP to perform fast continuous readout of the A/D FIFO memory and integration over specified intervals, synchronized to the probe's rotation in the magnetic field. C, C++ and Java code was written to control the data acquisition devices and to process a continuous stream of data. The paper summarizes the characteristics of the system and presents the results of initial tests and measurements.

  17. He Lung Imaging in an Open Access, Very-Low-Field Human Magnetic Resonance Imaging System

    E-Print Network [OSTI]

    Walsworth, Ronald L.

    3 He Lung Imaging in an Open Access, Very-Low-Field Human Magnetic Resonance Imaging System R. W. Butler,6 F. W. Hersman,4 and R. L. Walsworth1 The human lung and its functions are extremely sensitive lung restrict sub- jects to lying horizontally. Imaging of human lungs using inhaled laser-polarized 3

  18. Positive exchange bias and upward magnetic relaxation in a Fe-film/CoO-nanoparticle hybrid system

    E-Print Network [OSTI]

    Krishnan, Kannan M.

    Positive exchange bias and upward magnetic relaxation in a Fe-film/CoO- nanoparticle hybrid system exchange bias and upward magnetic relaxation in a Fe-film/CoO-nanoparticle hybrid system Wei Zhang) Heat-induced damping modification in yttrium iron garnet/platinum hetero-structures Appl. Phys. Lett

  19. A system for catheter tracking using magnetic resonance

    E-Print Network [OSTI]

    Rosas Trigueros Jorge Luis

    2002-01-01T23:59:59.000Z

    of the VI's. 35 36 3. 3 Peak detection. 38 3. 4 Sketch of the positioning system for vertical movement. . . 39 3. 5 Positioning system for vertical movement. 3. 6 Sketch of fiducial coil design. 40 42 4. 1 Cod-liver capsule tracking 1. 4. 2 Cod.... 69 70 72 LIST OF TABLES TABLE I Comparison between catheter tracking technologies. . . Page 11 II List of possible orientations from the read values. . 23 III VI's used by CATS . . 33 IV Global variables used by CATS. . 33 CHAPTER I...

  20. Frequency stabilization of spin-torque-driven oscillations by coupling with a magnetic nonlinear resonator

    SciTech Connect (OSTI)

    Kudo, Kiwamu, E-mail: kiwamu.kudo@toshiba.co.jp; Suto, Hirofumi; Nagasawa, Tazumi; Mizushima, Koichi; Sato, Rie [Corporate Research and Development Center, Toshiba Corporation, Kawasaki 212–8582 (Japan)

    2014-10-28T23:59:59.000Z

    The fundamental function of any oscillator is to produce a waveform with a stable frequency. Here, we show a method of frequency stabilization for spin-torque nano-oscillators (STNOs) that relies on coupling with an adjacent nanomagnet through the magnetic dipole–dipole interaction. It is numerically demonstrated that highly stable oscillations occur as a result of mutual feedback between an STNO and a nanomagnet. The nanomagnet acts as a nonlinear resonator for the STNO. This method is based on the nonlinear behavior of the resonator and can be considered as a magnetic analogue of an optimization scheme in nanoelectromechanical systems. The oscillation frequency is most stabilized when the nanomagnet is driven at a special feedback point at which the feedback noise between the STNO and resonator is completely eliminated.

  1. Pursuit and Synchronization in Hydrodynamic Dipoles

    E-Print Network [OSTI]

    Kanso, Eva

    2015-01-01T23:59:59.000Z

    We study theoretically the behavior of a class of hydrodynamic dipoles. This study is motivated by recent experiments on synthetic and biological swimmers in microfluidic \\textit{Hele-Shaw} type geometries. Under such confinement, a swimmer's hydrodynamic signature is that of a potential source dipole, and the long-range interactions among swimmers are obtained from the superposition of dipole singularities. Here, we recall the equations governing the positions and orientations of interacting asymmetric swimmers in doubly-periodic domains, and focus on the dynamics of swimmer pairs. We obtain two families of `relative equilibria'-type solutions that correspond to pursuit and synchronization of the two swimmers, respectively. Interestingly, the pursuit mode is stable for large tail swimmers whereas the synchronization mode is stable for large head swimmers. These results have profound implications on the collective behavior reported in several recent studies on populations of confined microswimmers.

  2. Precision Magnet Measurements for X-Band Accelerator Quadrupole Triplets

    SciTech Connect (OSTI)

    Marsh, R A; Anderson, S G; Armstrong, J P

    2012-05-16T23:59:59.000Z

    An X-band test station is being developed at LLNL to investigate accelerator optimization for future upgrades to mono-energetic gamma-ray (MEGa-Ray) technology at LLNL. Beamline magnets will include an emittance compensation solenoid, windowpane steering dipoles, and quadrupole magnets. Demanding tolerances have been placed on the alignment of these magnets, which directly affects the electron bunch beam quality. A magnet mapping system has been established at LLNL in order to ensure the delivered magnets match their field specification, and the mountings are aligned and capable of reaching the specified alignment tolerances. The magnet measurement system will be described which uses a 3-axis Lakeshore gauss probe mounted on a 3-axis translation stage. Alignment accuracy and precision will be discussed, as well as centering measurements and analysis. The dependence on data analysis over direct multi-pole measurement allows a significant improvement in useful alignment information. Detailed analysis of measurements on the beamline quadrupoles will be discussed, including multi-pole content both from alignment of the magnets, and the intrinsic level of multi-pole magnetic field.

  3. Tests of prototype SSC magnets

    SciTech Connect (OSTI)

    Strait, J.

    1987-04-24T23:59:59.000Z

    Results are presented from tests of the first two full length prototype SSC dipole magnets. Magnetic field measurements have been made at currents up to 2000 A. The two magnets achieved peak currents at 4.5K of 5790 A and 6450 A, respectively, substantially below the short sample limit of 6700 A. These peak values, however, could not be achieved reproducibly. Data are presented from studies performed to try to understand the poor quench performance.

  4. Apparatus and method for reducing inductive coupling between levitation and drive coils within a magnetic propulsion system

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2001-01-01T23:59:59.000Z

    An apparatus and method is disclosed for reducing inductive coupling between levitation and drive coils within a magnetic levitation system. A pole array has a magnetic field. A levitation coil is positioned so that in response to motion of the magnetic field of the pole array a current is induced in the levitation coil. A first drive coil having a magnetic field coupled to drive the pole array also has a magnetic flux which induces a parasitic current in the levitation coil. A second drive coil having a magnetic field is positioned to attenuate the parasitic current in the levitation coil by canceling the magnetic flux of the first drive coil which induces the parasitic current. Steps in the method include generating a magnetic field with a pole array for levitating an object; inducing current in a levitation coil in response to motion of the magnetic field of the pole array; generating a magnetic field with a first drive coil for propelling the object; and generating a magnetic field with a second drive coil for attenuating effects of the magnetic field of the first drive coil on the current in the levitation coil.

  5. Real Compton Scattering via Color Dipoles

    E-Print Network [OSTI]

    B. Z. Kopeliovich; Ivan Schmidt; M. Siddikov

    2009-08-24T23:59:59.000Z

    We study photoabsorption reaction and real Compton scattering (RCS) within the color dipole model. We rely on a photon wave function derived in the instanton vacuum model, and on the energy dependent phenomenological elastic dipole amplitude. Data for the photoabsorption cross section at high energies agree with our parameter free calculations. We also provide predictions for the differential RCS cross section. Although no data for small angle Compton scattering are available so far, this process can be measured in ultra-peripheral hadronic and nuclear collisions at the LHC.

  6. DIPOLE COLLAPSE AND DYNAMO WAVES IN GLOBAL DIRECT NUMERICAL SIMULATIONS

    SciTech Connect (OSTI)

    Schrinner, Martin; Dormy, Emmanuel [MAG (ENS/IPGP), LRA, Ecole Normale Superieure, 24 Rue Lhomond, 75252 Paris Cedex 05 (France); Petitdemange, Ludovic, E-mail: martin@schrinner.eu [Previously at Max-Planck-Institut fuer Astronomie, Koenigstuhl 17, 69117 Heidelberg, Germany. (Germany)

    2012-06-20T23:59:59.000Z

    Magnetic fields of low-mass stars and planets are thought to originate from self-excited dynamo action in their convective interiors. Observations reveal a variety of field topologies ranging from large-scale, axial dipoles to more structured magnetic fields. In this article, we investigate more than 70 three-dimensional, self-consistent dynamo models in the Boussinesq approximation obtained by direct numerical simulations. The control parameters, the aspect ratio, and the mechanical boundary conditions have been varied to build up this sample of models. Both strongly dipolar and multipolar models have been obtained. We show that these dynamo regimes in general can be distinguished by the ratio of a typical convective length scale to the Rossby radius. Models with a predominantly dipolar magnetic field were obtained, if the convective length scale is at least an order of magnitude larger than the Rossby radius. Moreover, we highlight the role of the strong shear associated with the geostrophic zonal flow for models with stress-free boundary conditions. In this case the above transition disappears and is replaced by a region of bistability for which dipolar and multipolar dynamos coexist. We interpret our results in terms of dynamo eigenmodes using the so-called test-field method. We can thus show that models in the dipolar regime are characterized by an isolated 'single mode'. Competing overtones become significant as the boundary to multipolar dynamos is approached. We discuss how these findings relate to previous models and to observations.

  7. Test Results of HD2, A High Field Nb3Sn Dipole with A 36 MM Bore

    SciTech Connect (OSTI)

    Ferracin, Paolo

    2008-05-19T23:59:59.000Z

    The Superconducting Magnet Program at Lawrence Berkeley National Laboratory (LBNL) has developed the 1 m long Nb{sub 3}Sn dipole magnet HD2. With tilted (flared) ends to avoid obstructing a 36 mm clear bore, HD2 represents a step towards the use of block-type coils in high-field accelerator magnets. The coil design has been optimized to minimize geometric harmonics and reduce the conductor peak field in the end region, resulting in an expected short sample dipole field of 15 T. The support structure is composed by an external aluminum shell pre-tensioned with pressurized bladders and interference keys, and by two stainless steel end plates compressing the coil ends through four aluminum axial rods. We report on magnet design, assembly, and test results, including training performance, quench locations, and strain gauge measurements.

  8. A cryogen-free ultralow-field superconducting quantum interference device magnetic resonance imaging system

    SciTech Connect (OSTI)

    Eom, Byeong Ho; Penanen, Konstantin; Hahn, Inseob, E-mail: ihahn@caltech.edu [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California 91109 (United States)

    2014-09-15T23:59:59.000Z

    Magnetic resonance imaging (MRI) at microtesla fields using superconducting quantum interference device (SQUID) detection has previously been demonstrated, and advantages have been noted. Although the ultralow-field SQUID MRI technique would not need the heavy superconducting magnet of conventional MRI systems, liquid helium required to cool the low-temperature detector still places a significant burden on its operation. We have built a prototype cryocooler-based SQUID MRI system that does not require a cryogen. The SQUID detector and the superconducting gradiometer were cooled down to 3.7 K and 4.3 K, respectively. We describe the prototype design, characterization, a phantom image, and areas of further improvements needed to bring the imaging performance to parity with conventional MRI systems.

  9. Test of a 1.8 Tesla, 400 Hz Dipole for a Muon Synchrotron

    E-Print Network [OSTI]

    D. J. Summers; L. M. Cremaldi; T. L. Hart; L. P. Perera; M. Reep; H. Witte; S. Hansen; M. L. Lopes; J. Reidy, Jr.

    2012-07-28T23:59:59.000Z

    A 1.8 T dipole magnet using thin grain oriented silicon steel laminations has been constructed as a prototype for a muon synchrotron ramping at 400 Hz. Following the practice in large 3 phase transformers and our own Opera-2d simulations, joints are mitred to take advantage of the magnetic properties of the steel which are much better in the direction in which the steel was rolled. Measurements with a Hysteresigraph 5500 and Epstein frame show a high magnetic permeability which minimizes stored energy in the yoke allowing the magnet to ramp quickly with modest voltage. Coercivity is low which minimizes hysteresis losses. A power supply with a fast Insulated Gate Bipolar Transistor (IGBT) switch and a capacitor was constructed. Coils are wound with 12 gauge copper wire. Thin wire and laminations minimize eddy current losses. The magnetic field was measured with a peak sensing Hall probe.

  10. Test of a 1.8 Tesla, 400 Hz Dipole for a Muon Synchrotron

    SciTech Connect (OSTI)

    Summers, D.J.; Cremaldi, L.M.; Hart, T.L.; Perera, L.P.; Reep, M.; /Mississippi U.; Witte, H.; /Brookhaven; Hansen, S.; Lopes, M.L.; /Fermilab; Reidy Jr., J.; /Oxford High School

    2012-05-01T23:59:59.000Z

    A 1.8 T dipole magnet using thin grain oriented silicon steel laminations has been constructed as a prototype for a muon synchrotron ramping at 400 Hz. Following the practice in large 3 phase transformers and our own Opera-2d simulations, joints are mitred to take advantage of the magnetic properties of the steel which are much better in the direction in which the steel was rolled. Measurements with a Hysteresigraph 5500 and Epstein frame show a high magnetic permeability which minimizes stored energy in the yoke allowing the magnet to ramp quickly with modest voltage. Coercivity is low which minimizes hysteresis losses. A power supply with a fast Insulated Gate Bipolar Transistor (IGBT) switch and a capacitor was constructed. Coils are wound with 12 gauge copper wire. Thin wire and laminations minimize eddy current losses. The magnetic field was measured with a peak sensing Hall probe.

  11. Low-noise pulsed pre-polarization magnet system for ultra-low field NMR

    SciTech Connect (OSTI)

    Sims, James R [Los Alamos National Laboratory; Schilling, Josef B [Los Alamos National Laboratory; Swenson, Charles A [Los Alamos National Laboratory; Gardner, David L [Los Alamos National Laboratory; Matlashov, Andrei N [Los Alamos National Laboratory; Ammerman, Curti N [Los Alamos National Laboratory

    2009-01-01T23:59:59.000Z

    A liquid cooled, pulsed electromagnet of solenoid configuration suitable for duty in an ultra-low field nuclear magnetic resonance system has been designed, fabricated and successfully operated. The magnet design minimizes Johnson noise, minimizes the hydrogen signal and incorporates minimal metal and no ferromagnetic materials. In addition, an acoustically quiet cooling system permitting 50% duty cycle operation was achieved by designing for single-phase, laminar flow, forced convection cooling. Winding, conductor splicing and epoxy impregnation techniques were successfully developed to produce a coil winding body with integral cooling passageways and adequate structural integrity. Issues of material compatibility, housing, coolant flow system and heat rejection system design will be discussed. Additionally, this pulsed electromagnet design has been extended to produce a boiling liquid cooled version in a paired solenoid configuration suitable for duty in an ultra-low field nuclear magnetic resonance system. This pair of liquid nitrogen cooled coils is currently being tested and commissioned. Issues of material compatibility, thermal insulation, thermal contraction, housing and coolant flow design are discussed.

  12. Design of HD2: a 15 T Nb3Sn dipole with a 35 mm bore

    SciTech Connect (OSTI)

    Sabbi, G.; Bartlett, S. E.; Caspi, S.; Dietderich, D. R.; Ferracin, P.; Gourlay, S. A.; Hannaford, C. R.; Hafalia, A. R.; Lietzke, A. F.; Mattafirri, S.; McInturff, A. D.; Scanlan, R.

    2005-06-01T23:59:59.000Z

    The Nb{sub 3}Sn dipole HD1, recently fabricated and tested at LBNL, pushes the limits of accelerator magnet technology into the 16 T field range, and opens the way to a new generation of HEP colliders. HD1 is based on a flat racetrack coil configuration and has a 10 mm bore. These features are consistent with the HD1 goals: exploring the Nb{sub 3}Sn conductor performance limits at the maximum fields and under high stress. However, in order to further develop the block-coil geometry for future high-field accelerators, the bore size has to be increased to 30-50 mm. With respect to HD1, the main R&D challenges are: (a) design of the coil ends, to allow a magnetically efficient cross-section without obstructing the beam path; (b) design of the bore, to support the coil against the pre-load force; (c) correction of the geometric field errors. HD2 represents a first step in addressing these issues, with a central dipole field above 15 T, a 35 mm bore, and nominal field harmonics within a fraction of one unit. This paper describes the HD2 magnet design concept and its main features, as well as further steps required to develop a cost-effective block-coil design for future high-field, accelerator-quality dipoles.

  13. Measurement of the Angular Dependence of the Dipole-Dipole Interaction Between Two Individual Rydberg Atoms at a F\\"orster Resonance

    E-Print Network [OSTI]

    Ravets, Sylvain; Barredo, Daniel; Lahaye, Thierry; Browaeys, Antoine

    2015-01-01T23:59:59.000Z

    We measure the angular dependence of the resonant dipole-dipole interaction between two individual Rydberg atoms with controlled relative positions. By applying a combination of static electric and magnetic fields on the atoms, we demonstrate the possibility to isolate a single interaction channel at a F\\"orster resonance, that shows a well-defined angular dependence. We first identify spectroscopically the F\\"orster resonance of choice and we then perform a direct measurement of the interaction strength between the two atoms as a function of the angle between the internuclear axis and the quantization axis. Our results show good agreement with the expected angular dependence $\\propto(1-3\\cos^2\\theta)$, and represent an important step towards quantum state engineering in two-dimensional arrays of individual Rydberg atoms.

  14. The Pygmy Dipole Resonance status and new experimental developments

    E-Print Network [OSTI]

    Zilges, Andreas

    Dipole Resonance (GDR) Phys. Rev. 71 (1947) 3 1947: Photo-Fission in Uranium #12;Giant Dipole Resonance radius · Slope of symmetry energy in EoS · Impact on nucleosynthesis S. Goriely, PLB 436 (1998) 10 E

  15. A design for a high voltage magnet coil ringer test set

    SciTech Connect (OSTI)

    Koska, W. [Fermi National Accelerator Lab., Batavia, IL (United States); Sims, R.E. [Superconducting Super Collider Lab., Dallas, TX (United States)

    1992-04-01T23:59:59.000Z

    By discharging a bank of charged capacitors through a high power SCR switch into an SSC dipole magnet assembly, it is possible to ``ring`` the coil and develop a voltage stress of greater than 50 volts turn-to-turn, thereby verifying the insulation integrity. We will present an overview of the test set design for a 2 kV isolated SCR firing circuit, including safety features, selectable capacitor banks, and digital waveform storage system. Results from testing typical coils and magnets will be included. Possible upgrades are also discussed.

  16. A design for a high voltage magnet coil ringer test set

    SciTech Connect (OSTI)

    Koska, W. (Fermi National Accelerator Lab., Batavia, IL (United States)); Sims, R.E. (Superconducting Super Collider Lab., Dallas, TX (United States))

    1992-04-01T23:59:59.000Z

    By discharging a bank of charged capacitors through a high power SCR switch into an SSC dipole magnet assembly, it is possible to ring'' the coil and develop a voltage stress of greater than 50 volts turn-to-turn, thereby verifying the insulation integrity. We will present an overview of the test set design for a 2 kV isolated SCR firing circuit, including safety features, selectable capacitor banks, and digital waveform storage system. Results from testing typical coils and magnets will be included. Possible upgrades are also discussed.

  17. New superconducting toroidal magnet system for IAXO, the international AXion observatory

    SciTech Connect (OSTI)

    Shilon, I.; Dudarev, A.; Silva, H.; Wagner, U.; Kate, H. H. J. ten [European Organization for Nuclear Research (CERN), CH-1211, Genčve 23 (Switzerland)

    2014-01-29T23:59:59.000Z

    Axions are hypothetical particles that were postulated to solve one of the puzzles arising in the standard model of particle physics, namely the strong CP (Charge conjugation and Parity) problem. The new International AXion Observatory (IAXO) will incorporate the most promising solar axions detector to date, which is designed to enhance the sensitivity to the axion-photon coupling by one order of magnitude beyond the limits of the current state-of-the-art detector, the CERN Axion Solar Telescope (CAST). The IAXO detector relies on a high-magnetic field distributed over a very large volume to convert solar axions into X-ray photons. Inspired by the successful realization of the ATLAS barrel and end-cap toroids, a very large superconducting toroid is currently designed at CERN to provide the required magnetic field. This toroid will comprise eight, one meter wide and twenty one meter long, racetrack coils. The system is sized 5.2 m in diameter and 25 m in length. Its peak magnetic field is 5.4 T with a stored energy of 500 MJ. The magnetic field optimization process to arrive at maximum detector yield is described. In addition, materials selection and their structure and sizing has been determined by force and stress calculations. Thermal loads are estimated to size the necessary cryogenic power and the concept of a forced flow supercritical helium based cryogenic system is given. A quench simulation confirmed the quench protection scheme.

  18. Gravitational Radiation from Oscillating Gravitational Dipole

    E-Print Network [OSTI]

    Fran De Aquino

    2002-10-05T23:59:59.000Z

    The concept of Gravitational Dipole is introduced starting from the recent discovery of negative gravitational mass (gr-qc/0005107 and physics/0205089). A simple experiment, a gravitational wave transmitter, to test this new concept of gravitational radiation source is presented.

  19. Colour dipoles and deeply virtual Compton scattering

    E-Print Network [OSTI]

    R. Sandapen

    2002-07-01T23:59:59.000Z

    I report on an analysis of Deeply Virtual Compton Scattering (DVCS) within the dipole model, done in collaboration with M. McDermott and G. Shaw. The two models considered here are distinct in their structure and implications. They both agree with the available cross-section data on DVCS from HERA. Predictions for various asymmetries are also given.

  20. The Levitated Dipole Experiment: Experiment and Theory

    E-Print Network [OSTI]

    along- the-field-line losses disappear (all losses become cross-field) and near- stationary density losses and LDX exhibits a dramatic peaking of density (and pressure). Fluctuations of density - Technical Capability Routine operation of superconducting dipole. Up to 3 hr float time ECRF heating: 17 k

  1. Co-Funding for the Conference on Magnetic Resonance in Biological Systems

    SciTech Connect (OSTI)

    Alan McLaughlin, Ph.D., Director, Division of Applied Science & Technology, NIBIB, NIH

    2008-10-01T23:59:59.000Z

    The XXIst International Conference on Magnetic Resonance in Biological Systems (ICMRBS 2005), '60th anniversary of the discovery of Nuclear Magnetic Resonance,' was held between 16 and 21 January 2005 in Hyderabad, India. The meeting focused on a broad range of magnetic resonance methods as applied to studies of biological processes related to human health. The biennial ICMRBS has become the major venue for discussion of advances in nuclear and electron magnetic resonance (NMR & EMR/EPR) studies of the structure, dynamics, and chemical properties of important classes of biomolecules. Magnetic resonance has become an established tool in structural biology, and its special importance derives from its ability to provide atomic level information. It is becoming increasingly evident that the dynamic features of biomolecules, their intermolecular interactions, and accessible conformations in solution are data of key importance in understanding molecular recognition and function. NMR, which is already contributing to approximately 25% of the new structures being deposited with the Protein Data Bank, is destined to be a major player in the post genomic structure age with its emphasis on structure and function. In-vivo magnetic resonance spectroscopy (MRS) and magnetic resonance imaging (MRI) results shed light on human metabolic processes and on the cellular ramifications of cancer, stroke, cardiovascular disease, and other pathologies. New methodologies in metabonomics may lead to development of new drugs and medical diagnosis. The ICMRBS is the one conference that brings together experts from high-resolution NMR, solid state NMR, EPR, in-vivo MRS and MRI, and developers of instrumentation, techniques, software, and databases. Symposia at this ICMRBS are designed to continue the fruitful cross-fertilization of ideas that has been so successful in driving the spectacular advances in this field. ICMRBS 2005 maintained the traditional format of poster sessions, and plenary lectures that highlight major advances in each of the major areas, and three parallel symposia that focused on particular biological systems, interfacial applications of magnetic resonance, and rapidly advancing technology. Funds provided partial travel support for 33 younger scientists from the U.S. (graduate students, postdoctoral research associates, and beginning faculty), selected from those who submitted accepted posters; 12 of these were invited to contribute oral presentations. Those receiving travel support were selected by a committee composed of the U.S. members of the International Advisory Committee for the meeting. Particular emphasis was placed on facilitating participation of minority and women scientists.

  2. A Nb3Sn DIPOLE MAGNET REACTED AFTER WINDING

    E-Print Network [OSTI]

    Taylor, C.

    2010-01-01T23:59:59.000Z

    IbId. , pp . 1410-1416. C. Taylor, R. Heuser, S. Caspl, WREACTED AFTER WINDING C. Taylor, R. Scanlan, C. Peters, R.REACTED AFTER WINDING" C. Taylor, R. Scanlan, C. Peters, R.

  3. Magnetic Field Measurements and Analysis For an Aladdin Dipole...

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

    which is often longer than 1 m. Because of the multiplying effect of this boom, the control program makes corrections for every destination point. The amounts of the corrections...

  4. Chains with loops - synthetic magnetic fluxes and topological order in one-dimensional spin systems

    E-Print Network [OSTI]

    Tobias Grass; Christine Muschik; Alessio Celi; Ravindra Chhajlany; Maciej Lewenstein

    2015-04-14T23:59:59.000Z

    Engineering topological quantum order has become a major field of physics. Many advances have been made by synthesizing gauge fields in cold atomic systems. Here, we carry over these developments to other platforms which are extremely well suited for quantum engineering, namely trapped ions and nano-trapped atoms. Since these systems are typically one-dimensional, the action of artificial magnetic fields has so far received little attention. However, exploiting the long-range nature of interactions, loops with non-vanishing magnetic fluxes become possible even in one-dimensional settings. This gives rise to intriguing phenomena, such as fractal energy spectra, flat bands with localized edge states, and topological many-body states. We elaborate on a simple scheme for generating the required artificial fluxes by periodically driving an XY spin chain. Concrete estimates demonstrating the experimental feasibility for trapped ions and atoms in waveguides are given.

  5. System and method for non-destructive evaluation of surface characteristics of a magnetic material

    DOE Patents [OSTI]

    Jiles, David C. (Ames, IA); Sipahi, Levent B. (Ames, IA)

    1994-05-17T23:59:59.000Z

    A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.

  6. Identification of rotordynamic forces in a flexible rotor system using magnetic bearings

    E-Print Network [OSTI]

    Zutavern, Zachary Scott

    2009-06-02T23:59:59.000Z

    IDENTIFICATION OF ROTORDYNAMIC FORCES IN A FLEXIBLE ROTOR SYSTEM USING MAGNETIC BEARINGS A Dissertation by ZACHARY SCOTT ZUTAVERN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment... by ZACHARY SCOTT ZUTAVERN Submitted to the Office of Graduate Studies of Texas A&M University in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Approved by: Chair of Committee, Dara Childs Committee...

  7. Cryogenic techniques for large superconducting magnets in space

    SciTech Connect (OSTI)

    Green, M.A.

    1988-12-01T23:59:59.000Z

    A large superconducting magnet is proposed for use in a particle astrophysics experiment, ASTROMAG, which is to be mounted on the United States Space Station. This experiment will have a two-coil superconducting magnet with coils which are 1.3 to 1.7 meters in diameter. The two-coil magnet will have zero net magnetic dipole moment. The field 15 meters from the magnet will approach earth's field in low earth orbit. The issue of high Tc superconductor will be discussed in the paper. The reasons for using conventional niobium-titanium superconductor cooled with superfluid helium will be presented. Since the purpose of the magnet is to do particle astrophysics, the superconducting coils must be located close to the charged particle detectors. The trade off between the particle physics possible and the cryogenic insulation around the coils is discussed. As a result, the ASTROMAG magnet coils will be operated outside of the superfluid helium storage tank. The fountain effect pumping system which will be used to cool the coil is described in the report. Two methods for extending the operating life of the superfluid helium dewar are discussed. These include: operation with a third shield cooled to 90 K with a sterling cycle cryocooler, and a hybrid cryogenic system where there are three hydrogen-cooled shields and cryostat support heat intercept points. Both of these methods will extend the ASTROMAG cryogenic operating life from 2 years to almost 4 years. 14 refs., 8 figs., 4 tabs.

  8. Fabrication and Test of 90-mm Nb3Sn Quadrupole Model Based on Dipole-type Collar

    SciTech Connect (OSTI)

    Bossert, R.; Andreev, N.; Chlachidze, G.; Kashikhin, V.S.; Kashikhin, V.V.; Lamm, M.J.; Nobrega, F.; Novitski, I.; Tartaglia, M.; Velev, G.; Zlobin, A.V.; /Fermilab

    2010-07-29T23:59:59.000Z

    A series of 90-mm TQC quadrupole models with a collar-based mechanical structure has been fabricated and tested within the framework of the US-LHC Accelerator Research Program (LARP) using quadrupole-symmetric stainless steel collar laminations. This paper describes the design features, construction and test of TQC02Eb, the first TQC made with dipole-type collar and collaring techniques. Magnet test includes quench performance and field quality measurements at 4.5 and 1.9 K. Results of model performance for TQC quadrupoles based on dipole-type and quadrupole-type collars are compared and discussed.

  9. Synthesis and simulation of a two-level magnetic control system for tokamak-reactor plasma

    SciTech Connect (OSTI)

    Mitrishkin, Yu. V. [Russian Academy of Sciences, V.A. Trapeznikov Institute of Control Sciences (Russian Federation); Korostelev, A. Ya. [Bauman Moscow State Technical University (Russian Federation); Dokuka, V. N.; Khayrutdinov, R. R. [Troitsk Institute for Innovation and Fusion Research (Russian Federation)

    2011-04-15T23:59:59.000Z

    Synthesis and simulation of a hierarchical (two-level) magnetic system for controlling a tokamakreactor plasma throughout the entire divertor discharge stage, including the plasma current ramp-up phase, are carried out. The plasma vertical velocity is stabilized about zero by using a proportional controller in a scalar control loop. The gain of the controller-the coefficient that ensures the required stability margins-is found by using a second-order linear model constructed by solving the identification problem on the basis of numerical experiments carried out with the DINA plasmophysical computer code. The internal cascade (the lower level of the system) for tracking the scenario currents in the poloidal magnetic field coils is synthesized by using the complete dynamic channel decoupling method. The external cascade (the upper level of the system) for tracking the plasma current and shape is synthesized by using the method of pseudoseparation of the control channels and the multidimensional diagonal proportional-integral controller, with proportional, integrating, and double integrating units connected in parallel in each channel. In the hierarchical control system, the lower level (the internal cascade) is subordinated to the upper level (the external cascade). The external cascade acts on the internal one by the signals that set the required currents in the coils of the central solenoid and of the poloidal magnetic field in order to ensure the required plasma current and shape in accordance with the output signals from the plant, which are transmitted through the vector feedback channel. The lower level is aimed exclusively at tracking the reference inputs by tracking the currents in the control coils. An operating mode of the system under the conditions of current saturation in the control coils is proposed and implemented. Results are presented from numerical simulations of the two-level (cascade) control system for reference scenario no. 2 of the ITER database (www.iter.org) with the DINA nonlinear code.

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

    E-Print Network [OSTI]

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

    2014-07-21T23:59:59.000Z

    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.

  11. Tokamak Physics EXperiment (TPX): Toroidal field magnet design, development and manufacture. SDRL 15, System design description. Volume 1

    SciTech Connect (OSTI)

    NONE

    1995-09-22T23:59:59.000Z

    This System Design Description, prepared in accordance with the TPX Project Management Plan provides a summary or TF Magnet System design features at the conclusion of Phase I, Preliminary Design and Manufacturing Research. The document includes the analytical and experimental bases for the design, and plans for implementation in final design, manufacturing, test, and magnet integration into the tokamak. Requirements for operation and maintenance are outlined, and references to sources of additional information are provided.

  12. Multiple frequency printed slot and dipole antennas

    E-Print Network [OSTI]

    Kolsrud, Arild

    1997-01-01T23:59:59.000Z

    . Analysis. . D. Single Frequency Slot Antenna. , , , 32 . 41 E. Dual Frequency Slot Antenna. F. Chapter Summary. 48 Page CHAPTER IV PRINTED CPW-FED CPS DIPOLE. . . . . . . 53 A. Introduction. 53 B. Background. 54 C. Analysis. . D. Single... on the structure affects the performance by looking at the current distribution. Far-field radiation patterns of a structure can be calculated from the current distribution output data file. C. Chapter Summary Sonnet is mainly used for circuit structures, since...

  13. Superconducting helical solenoid systems for muon cooling experiment at Fermilab

    SciTech Connect (OSTI)

    Kashikhin, Vladimir S.; Andreev, Nikolai; /Fermilab; Johnson, Rolland P.; /MUONS Inc., Batavia; Kashikhin, Vadim V.; Lamm, Michael J.; Romanov, Gennady; Yonehara, Katsuya; Zlobin, Alexander V.; /Fermilab

    2007-08-01T23:59:59.000Z

    Novel configurations of superconducting magnet system for Muon Beam Cooling Experiment is under design at Fermilab. The magnet system has to generate longitudinal and transverse dipole and quadrupole helical magnetic fields providing a muon beam motion along helical orbit. It was found that such complicated field configuration can be formed by a set of circular coils shifted in transverse directions in such a way that their centers lay on the center of the helical beam orbit. Closed beam orbit configurations were also proposed and investigated. This paper describes the magnetic and mechanical designs and parameters of such magnetic system based on a NbTi Rutherford type cable. The helical solenoid fabrication, assembly and quench protection issues are presented.

  14. Homogenisation of a Row of Dislocation Dipoles

    E-Print Network [OSTI]

    Stephen Jonathan Chapman; Yang Xiang; Yichao Zhu

    2015-04-27T23:59:59.000Z

    Conventional discrete-to-continuum approaches have seen their limitation in describing the collective behaviour of the multi-polar configurations of dislocations, which are widely observed in crystalline materials. The reason is that dislocation dipoles, which play an important role in determining the mechanical properties of crystals, often get smeared out when traditional homogenisation methods are applied. To address such difficulties, the collective behaviour of a row of dislocation dipoles is studied by using matched asymptotic techniques. The discrete-to-continuum transition is facilitated by introducing two field variables respectively describing the dislocation pair density potential and the dislocation pair width. It is found that the dislocation pair width evolves much faster than the pair density. Such hierarchy in evolution time scales enables us to describe the dislocation dynamics at the coarse-grained level by an evolution equation for the slowly varying variable (the pair density) coupled with an equilibrium equation for the fast varying variable (the pair width). The time-scale separation method adopted here paves a way for properly incorporating dipole-like (zero net Burgers vector but non-vanishing) dislocation structures, known as the statistically stored dislocations (SSDs) into macroscopic models of crystal plasticity in three dimensions. Moreover, the natural transition between different equilibrium patterns found here may also shed light on understanding the emergence of the persistent slip bands (PSBs) in fatigue metals induced by cyclic loads.

  15. Results from the Levitated Dipole Experiment MIT Plasma Science and Fusion Center

    E-Print Network [OSTI]

    lead naturally to breadth in science and technology · Example: Confinement in the field of a levitated dipole · Unique physics illuminated by closed field line systems · Unique technology challenges is centrally peaked with n ~ 1/V ~ R-4 · Farley et al. (1970): Turbulence causes strong inward particle pinch

  16. Magnetic Measurement Results of the LCLS Undulator Quadrupoles

    SciTech Connect (OSTI)

    Anderson, Scott; Caban, Keith; Nuhn, Heinz-Dieter; Reese, Ed; Wolf, Zachary; /SLAC; ,

    2011-08-18T23:59:59.000Z

    This note details the magnetic measurements and the magnetic center fiducializations that were performed on all of the thirty-six LCLS undulator quadrupoles. Temperature rise, standardization reproducibility, vacuum chamber effects and magnetic center reproducibility measurements are also presented. The Linac Coherent Light Source (LCLS) undulator beam line has 33 girders, each with a LCLS undulator quadrupole which focuses and steers the beam through the beam line. Each quadrupole has main quadrupole coils, as well as separate horizontal and vertical trim coils. Thirty-six quadrupoles, thirty-three installed and three spares were, manufactured for the LCLS undulator system and all were measured to confirm that they met requirement specifications for integrated gradient, harmonics and for magnetic center shifts after current changes. The horizontal and vertical dipole trims of each quadrupole were similarly characterized. Each quadrupole was also fiducialized to its magnetic center. All characterizing measurements on the undulator quads were performed with their mirror plates on and after a standardization of three cycles from -6 to +6 to -6 amps. Since the undulator quadrupoles could be used as a focusing or defocusing magnet depending on their location, all quadrupoles were characterized as focusing and as defocusing quadrupoles. A subset of the undulator quadrupoles were used to verify that the undulator quadrupole design met specifications for temperature rise, standardization reproducibility and magnetic center reproducibility after splitting. The effects of the mirror plates on the undulator quadrupoles were also measured.

  17. Measurements of magnetic field alignment

    SciTech Connect (OSTI)

    Kuchnir, M.; Schmidt, E.E.

    1987-11-06T23:59:59.000Z

    The procedure for installing Superconducting Super Collider (SSC) dipoles in their respective cryostats involves aligning the average direction of their field with the vertical to an accuracy of 0.5 mrad. The equipment developed for carrying on these measurements is described and the measurements performed on the first few prototypes SSC magnets are presented. The field angle as a function of position in these 16.6 m long magnets is a characteristic of the individual magnet with possible feedback information to its manufacturing procedure. A comparison of this vertical alignment characteristic with a magnetic field intensity (by NMR) characteristic for one of the prototypes is also presented. 5 refs., 7 figs.

  18. Method and system for controlling start of a permanent magnet machine

    DOE Patents [OSTI]

    Walters, James E.; Krefta, Ronald John

    2003-10-28T23:59:59.000Z

    Method and system for controlling a permanent magnet machine are provided. The method provides a sensor assembly for sensing rotor sector position relative to a plurality of angular sectors. The method further provides a sensor for sensing angular increments in rotor position. The method allows starting the machine in a brushless direct current mode of operation using a calculated initial rotor position based on an initial angular sector position information from the sensor assembly. Upon determining a transition from the initial angular sector to the next angular sector, the method allows switching to a sinusoidal mode of operation using rotor position based on rotor position information from the incremental sensor.

  19. Method and system for controlling a permanent magnet machine during fault conditions

    DOE Patents [OSTI]

    Krefta, Ronald John; Walters, James E.; Gunawan, Fani S.

    2004-05-25T23:59:59.000Z

    Method and system for controlling a permanent magnet machine driven by an inverter is provided. The method allows for monitoring a signal indicative of a fault condition. The method further allows for generating during the fault condition a respective signal configured to maintain a field weakening current even though electrical power from an energy source is absent during said fault condition. The level of the maintained field-weakening current enables the machine to operate in a safe mode so that the inverter is protected from excess voltage.

  20. 30-MJ superconducting magnetic-energy-storage stabilizing system: an overview

    SciTech Connect (OSTI)

    Roger, J.D.; Boenig, H.J.; Dean, J.W.; Schermer, R.I.; Annestrand, S.A.; Hauer, J.F.; Miller, B.L.

    1983-01-01T23:59:59.000Z

    The 30-MJ superconducting magnetic-energy-storage (SMES) system was devised as an alternate means to modulate the Bonneville Power Administration (BPA) Pacific AC Intertie, a part of the Western US Power System, to prevent undamped power oscillations at 0.35 Hz that were observed to be associated with high power transmission. The SMES system was installed at the BPA Tacoma Substation and successfully operated as an experimental device to initiate tests to determine power system dynamics, to investigate their variability, to assess system response to SMES modulation with a major variable load, and to use SMES to develop stability-control techniques. The system has been operated at frequencies of 0.1 to 1.0 Hz at power levels of +- 8.3 MW with a parallel modulation of the converter bridges and up to 9.5 MW reactive power together with +- 4.5 MW real power in constant VAR mode with buck-boost modulation of the bridges. The coil has been charged at a maximum rate of 11.8 MW. Operation of the SMES system is now under BPA jurisdiction, and all hardware has been transferred to BPA.

  1. Vortex dipoles by PIV method Click here to see the images and the short movies from this lab

    E-Print Network [OSTI]

    deYoung, Brad

    Introduction A vortex dipole is a jet flow with a system of two vortices of opposite sign at its front. Vortex of density stratification. The simplest case of stratification is a two-layer system. A Plexiglas tank a two-layer system without mixing the fluids, one can float a sheet of paper on top of the salt water

  2. Electro-mechanical energy conversion system having a permanent magnet machine with stator, resonant transfer link and energy converter controls

    DOE Patents [OSTI]

    Skeist, S. Merrill; Baker, Richard H.

    2006-01-10T23:59:59.000Z

    An electro-mechanical energy conversion system coupled between an energy source and an energy load comprising an energy converter device including a permanent magnet induction machine coupled between the energy source and the energy load to convert the energy from the energy source and to transfer the converted energy to the energy load and an energy transfer multiplexer to control the flow of power or energy through the permanent magnetic induction machine.

  3. On the Electrodynamics of Moving Permanent Dipoles in External Electromagnetic Fields

    E-Print Network [OSTI]

    Mansuripur, Masud

    2014-01-01T23:59:59.000Z

    The classical theory of electrodynamics is built upon Maxwell's equations and the concepts of electromagnetic field, force, energy and momentum, which are intimately tied together by Poynting's theorem and the Lorentz force law. Whereas Maxwell's macroscopic equations relate the electric and magnetic fields to their material sources (i.e., charge, current, polarization and magnetization), Poynting's theorem governs the flow of electromagnetic energy and its exchange between fields and material media, while the Lorentz law regulates the back-and-forth transfer of momentum between the media and the fields. The close association of momentum with energy thus demands that the Poynting theorem and the Lorentz law remain consistent with each other, while, at the same time, ensuring compliance with the conservation laws of energy, linear momentum, and angular momentum. This paper shows how a consistent application of the aforementioned laws of electrodynamics to moving permanent dipoles (both electric and magnetic) b...

  4. Interaction of biological systems with static and ELF electric and magnetic fields

    SciTech Connect (OSTI)

    Anderson, L.E.; Kelman, B.J.; Weigel, R.J. (eds.)

    1987-01-01T23:59:59.000Z

    Although background levels of atmospheric electric and geomagnetic field levels are extremely low, over the past several decades, human beings and other life forms on this planet have been subjected to a dramatically changing electromagnetic milieu. An exponential increase in exposure to electromagnetic fields has occurred, largely because of such technological advances as the growth of electrical power generation and transmission systems, the increased use of wireless communications, and the use of radar. In addition, electromagnetic field generating devices have proliferated in industrial plants, office buildings, homes, public transportation systems, and elsewhere. Although significant increases have occurred in electromagnetic field strenghths spanning all frequency ranges, this symposium addresses only the impact of these fields at static and extremely low frequencies (ELF), primarily 50 and 60 Hz. This volume contains the proceedings of the symposium entitled /open quotes/Interaction of biological systems with static and ELF electric and magnetic fields/close quotes/. The purpose of the symposium was to provide a forum for discussions of all aspects of research on the interaction of static and ELF electromagnetic fields with biological systems. These systems include simple biophysical models, cell and organ preparations, whole animals, and man. Dosimetry, exposure system design, and artifacts in ELF bioeffects research were also addressed, along with current investigations that examine fundamental mechanisms of interactions between the fields and biological processes. Papers are indexed separately.

  5. Intrinsic Electric Dipole Moments of Paramagnetic Atoms: Rubidium and Cesium

    E-Print Network [OSTI]

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

    2008-04-07T23:59:59.000Z

    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.

  6. Apparatus for detecting a magnetic anomaly contiguous to remote location by squid gradiometer and magnetometer systems

    DOE Patents [OSTI]

    Overton, Jr., William C. (Los Alamos, NM); Steyert, Jr., William A. (Los Alamos, NM)

    1984-01-01T23:59:59.000Z

    A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.

  7. Array of dipoles near a hyperbolic metamaterial: Evanescent-to-propagating Floquet wave transformation

    E-Print Network [OSTI]

    Guclu, Caner; Capolino, Filippo

    2013-01-01T23:59:59.000Z

    We investigate the capabilities of hyperbolic metamaterials (HMs) to couple near-fields (i.e., evanescent waves) emitted by a two-dimensional periodic array of electric dipoles to propagating waves. In particular, large order Floquet harmonics with transverse magnetic (TM) polarization, that would be evanescent in free space and therefore confined near the array surface, are transformed into propagating spectrum inside the HM, and thus carry power away. Because of this property, independent of the finite or infinite extent of the HM, the power generated by an array of elementary electric dipoles is strongly enhanced when the array is located near a HM surface and is mostly directed into the HM. In particular, the power coupled to the HM exhibits narrow frequency features that can be employed in detection applications. The results shown in this paper provide a clear signature on wave dynamics in HMs. A link between the results pertaining to the case of an isolated dipole on top of HM and the planar array is fo...

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

    SciTech Connect (OSTI)

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

    2014-10-06T23:59:59.000Z

    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.

  9. Ultrafast Magnetic Light

    E-Print Network [OSTI]

    Makarov, Sergey V; Krasnok, Alexander E; Belov, Pavel A

    2015-01-01T23:59:59.000Z

    We propose a novel concept for efficient dynamic tuning of optical properties of a high refractive index subwavelength nanoparticle with a magnetic Mie-type resonance by means of femtosecond laser radiation. This concept is based on ultrafast generation of electron-hole plasma within such nanoparticle, drastically changing its transient dielectric permittivity. This allows to manipulate by both electric and magnetic nanoparticle responses, resulting in dramatic changes of its extinction cross section and scattering diagram. Specifically, we demonstrate the effect of ultrafast switching-on a Huygens source in the vicinity of the magnetic dipole resonance. This approach enables to design ultrafast and compact optical switchers and modulators based on the "ultrafast magnetic light" concept.

  10. Abstract--The charging coil (C-coil) for the joint Columbia University/MIT Levitated Dipole Experiment (LDX) is under

    E-Print Network [OSTI]

    1 Abstract--The charging coil (C-coil) for the joint Columbia University/MIT Levitated Dipole) is a new, innovative magnetic confinement fusion experiment being designed, jointly by Columbia University@psfc.mit.edu). D. Garnier is with Columbia University, presently at MIT PSFC, Cambridge, MA 02139, USA (e

  11. Possible Constraints on Neutron Electric Dipole Moment from Pulsar Radiation

    E-Print Network [OSTI]

    C. Sivaram

    2010-02-12T23:59:59.000Z

    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.

  12. Structural, thermodynamic, mechanical, and magnetic properties of FeW system

    SciTech Connect (OSTI)

    Ren, Q. Q.; Fan, J. L.; Han, Y.; Gong, H. R., E-mail: gonghr@csu.edu.cn [State Key Laboratory of Powder Metallurgy, Central South University, Changsha, Hunan 410083 (China)

    2014-09-07T23:59:59.000Z

    The Fe-W system is systematically investigated through a combined use of first-principles calculation, cluster expansion, special quasirandom structures, and experiments. It is revealed that the ferromagnetic state of BCC Fe-W solid solution has lower heat of formation than its nonmagnetic state within the entire composition range, and intermetallic ?-Fe{sub 2}W and ?-Fe{sub 7}W{sub 6} phases are energetically favorable with negative heats of formation. Calculations also show that the Fe-W solid solution has much lower coefficient of thermal expansion than its mechanical mixture, and that the descending sequence of temperature-dependent elastic moduli of each Fe-W solid solution is E?>?G?>?B. Moreover, magnetic state should have an important effect on mechanical properties of Fe-W phases, and electronic structures can provide a deeper understanding of various properties of Fe-W. The derived results agree well with experimental observations, and can clarify two experimental controversies regarding structural stability and magnetic property of Fe-W phases in the literature.

  13. The Vlasov-Maxwell system with strong initial magnetic field. Guiding-center approximation

    E-Print Network [OSTI]

    Bostan, Mihai

    @univ-fcomte.fr 1 #12;duction through the thermonuclear fusion process. Two ways are currently explored for this: the inertial confinement fusion (ICF) and the magnetic confinement fusion (MCF). The magnetic confinement

  14. Upgrade of the extraction system of permanent magnet electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Zhang, M.; Peng, S. X.; Song, Z. Z.; Yuan, Z. X.; Zhou, Q. F.; Lu, P. N.; Xu, R.; Zhao, J.; Yu, J. X.; Chen, J. E.; Guo, Z. Y.; Lu, Y. R. [State Key Laboratory of Nuclear Physics and Technology and Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Ren, H. T. [State Key Laboratory of Nuclear Physics and Technology and Institute of Heavy Ion Physics, Peking University, Beijing 100871 (China); Graduate University of Chinese Academy of Sciences, Beijing 100049 (China)

    2010-02-15T23:59:59.000Z

    A set of new ion extraction electrodes have been designed for the permanent magnetic electron cyclotron resonance ion source at Peking University to improve beam quality and transmission. PBGUNS has been used to optimize the extraction electrodes and simulate the beam behavior at the extraction region. The experiments showed that with the new system, the beam half divergence angle can be less than 40 mrad and the normalized rms emittance is about 0.13{pi} mm mrad when the extracted current is 100 mA at 50 keV in pulse mode. The voltage of the suppression electrode has great effect on beam divergence. The effect of the microwave power and gas flow is also studied.

  15. Few-Body Bound States of Dipole-Dipole Interacting Rydberg Atoms

    E-Print Network [OSTI]

    Martin Kiffner; Mingxia Huo; Wenhui Li; Dieter Jaksch

    2014-07-08T23:59:59.000Z

    We show that the resonant dipole-dipole interaction can give rise to bound states between two and three Rydberg atoms with non-overlapping electron clouds. The dimer and trimer states arise from avoided level crossings between states converging to different fine structure manifolds in the limit of separated atoms. We analyze the angular dependence of the potential wells, characterize the quantum dynamics in these potentials and discuss methods for their production and detection. Typical distances between the atoms are of the order of several micrometers which can be resolved in state-of-the-art experiments. The potential depths and typical oscillation frequencies are about one order of magnitude larger as compared to the dimer and trimer states investigated in [PRA $\\textbf{86}$ 031401(R) (2012)] and [PRL $\\textbf{111}$ 233003 (2014)], respectively. We find that the dimer and trimer molecules can be aligned with respect to the axis of a weak electric field.

  16. Electric Dipole Radiation from Spinning Dust Grains

    E-Print Network [OSTI]

    B. T. Draine; A. Lazarian

    1998-02-18T23:59:59.000Z

    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.

  17. MAGNET/CRYOCOOLER INTEGRATIONFOR THERMAL STABILITY IN CONDUCTION-COOLED SYSTEMS

    E-Print Network [OSTI]

    Chang, Ho-Myung

    The stability conditions that take into accounts the size of superconducting magnets and the refrigeration the refrigeration, causing a rise in the temperature of the magnet winding and leading to burnout. It is shown of the magnet materials and the refrigeration characteristics of the cryocooler. A useful graphical scheme

  18. Superconducting magnet

    DOE Patents [OSTI]

    Satti, John A. (Naperville, IL)

    1980-01-01T23:59:59.000Z

    A superconducting magnet designed to produce magnetic flux densities of the order of 4 to 5 Webers per square meter is constructed by first forming a cable of a plurality of matrixed superconductor wires with each wire of the plurality insulated from each other one. The cable is shaped into a rectangular cross-section and is wound with tape in an open spiral to create cooling channels. Coils are wound in a calculated pattern in saddle shapes to produce desired fields, such as dipoles, quadrupoles, and the like. Wedges are inserted between adjacent cables as needed to maintain substantially radial placement of the long dimensions of cross sections of the cables. After winding, individual strands in each of the cables are brought out to terminals and are interconnected to place all of the strands in series and to maximize the propagation of a quench by alternating conduction from an inner layer to an outer layer and from top half to bottom half as often as possible. Individual layers are separated from others by spiraled aluminum spacers to facilitate cooling. The wound coil is wrapped with an epoxy tape that is cured by heat and then machined to an interference fit with an outer aluminum pipe which is then affixed securely to the assembled coil by heating it to make a shrink fit. In an alternate embodiment, one wire of the cable is made of copper or the like to be heated externally to propagate a quench.

  19. A biofilm microreactor system for simultaneous electrochemical and nuclear magnetic resonance techniques

    SciTech Connect (OSTI)

    Renslow, Ryan S.; Babauta, Jerome T.; Majors, Paul D.; Mehta, Hardeep S.; Ewing, R. James; Ewing, Thomas; Mueller, Karl T.; Beyenal, Haluk

    2014-01-30T23:59:59.000Z

    In order to fully understand electrochemically active biofilms and the limitations to their scale-up in industrial biofilm reactors, a complete picture of the microenvironments inside the biofilm is needed. Nuclear magnetic resonance (NMR) techniques are ideally suited for the study of biofilms and for probing their microenvironments because these techniques allow for non-invasive interrogation and in situ monitoring with high resolution. By combining NMR with simultaneous electrochemical techniques, it is possible to sustain and study live electrochemically active biofilms. Here, we introduce a novel biofilm microreactor system that allows for simultaneous electrochemical and NMR techniques (EC-NMR) at the microscale. Microreactors were designed with custom radiofrequency resonator coils, which allowed for NMR measurements of biofilms growing on polarized gold electrodes. For an example application of this system, we grew Geobacter sulfurreducens biofilms. NMR was used to investigate growth media flow velocities, which were compared to simulated laminar flow, and electron donor concentrations inside the biofilms. We use Monte Carlo error analysis to estimate standard deviations of the electron donor concentration measurements within the biofilm. The EC-NMR biofilm microreactor system can ultimately be used to correlate extracellular electron transfer rates with metabolic reactions and explore extracellular electron transfer mechanisms.

  20. A magnetically shielded room with ultra low residual field and gradient

    SciTech Connect (OSTI)

    Altarev, I.; Chesnevskaya, S.; Gutsmiedl, E.; Kuchler, F.; Lins, T.; Marino, M.; McAndrew, J.; Niessen, B.; Paul, S.; Petzoldt, G.; Singh, J.; Stoepler, R.; Stuiber, S.; Sturm, M.; Taubenheim, B. [Physikdepartment, Technische Universität München, D-85748 Garching (Germany); Babcock, E. [Jülich Center for Neutron Science, Lichtenbergstrasse 1, D-85748 Garching (Germany); Beck, D.; Sharma, S. [Physics Department, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States); Burghoff, M.; Fan, I. [Physikalisch-Technische Bundesanstalt Berlin, D-10587 Berlin (Germany); and others

    2014-07-15T23:59:59.000Z

    A versatile and portable magnetically shielded room with a field of (700 ± 200) pT within a central volume of 1 m × 1 m × 1 m and a field gradient less than 300 pT/m, achieved without any external field stabilization or compensation, is described. This performance represents more than a hundredfold improvement of the state of the art for a two-layer magnetic shield and provides an environment suitable for a next generation of precision experiments in fundamental physics at low energies; in particular, searches for electric dipole moments of fundamental systems and tests of Lorentz-invariance based on spin-precession experiments. Studies of the residual fields and their sources enable improved design of future ultra-low gradient environments and experimental apparatus. This has implications for developments of magnetometry beyond the femto-Tesla scale in, for example, biomagnetism, geosciences, and security applications and in general low-field nuclear magnetic resonance (NMR) measurements.

  1. POWER SUPPLY SYSTEM FOR CORRECTING MAGNETS OF VEPP-2000 O. Belikov, D. Berkaev, V. Kozak, A. Medvedko, BINP, Novosibirsk, Russia

    E-Print Network [OSTI]

    Kozak, Victor R.

    POWER SUPPLY SYSTEM FOR CORRECTING MAGNETS OF VEPP-2000 COMPLEX O. Belikov, D. Berkaev, V. Kozak, A is corrected with the help of correcting windings. Each winding is powered from an individual, four-quadrant current source (power amplifier) of the PA-6 or PA-20 type. The current sources are made with up

  2. MODELING LIQUID METAL CORROSION IN A FERRITIC STEEL PbLi SYSTEM WITH AND WITHOUT A MAGNETIC FIELD

    E-Print Network [OSTI]

    Abdou, Mohamed

    MODELING LIQUID METAL CORROSION IN A FERRITIC STEEL ­ PbLi SYSTEM WITH AND WITHOUT A MAGNETIC FIELD associated with corrosion of ferritic steel in the flowing eutectic alloy lead-lithium (PbLi). New computer to perform more analysis and comparisons against available experimental data on corrosion in various flow

  3. Ionospheric currents correlated with geomagnetic induced currents; Freja magnetic field measurements and the sunburst monitor system

    SciTech Connect (OSTI)

    Zanetti, L.J.; Potemra, T.A.; Anderson, B.J.; Erlandson, R.E.; Holland, D.B. [Johns Hopkins Univ., Laurel, MD (United States)] [Johns Hopkins Univ., Laurel, MD (United States); Acuna, M.H. [NASA/Goddard Space Flight Center, Greenbelt, MD (United States)] [NASA/Goddard Space Flight Center, Greenbelt, MD (United States); Kappenman, J. [Minnesota Power, Duluth, MN (United States)] [Minnesota Power, Duluth, MN (United States); Lesher, R.; Feero, B. [Electric Research and Management, Inc., State College, PA (United States)] [Electric Research and Management, Inc., State College, PA (United States)

    1994-08-15T23:59:59.000Z

    Temporal and spatial fluctuations of large-scale electric currents totaling millions of amperes in the ionosphere have long been known to induce current and voltage in the Earth`s surface and on large manmade conductive structures. A strong, persistent solar wind can interact with the geomagnetic environment and produce auroral zone currents at mid latitudes. Presented here is a specific correlation of ionospheric auroral currents inferred from magnetic field measurements from the Swedish Freja satellite and induced current in the electric power distribution system on the east coast of the United States, in particular the Chalk Point, Maryland, transformer station. The event discussed here registered a Kp level of 6 to 8 and occurred on April 4-5, 1993. An important aspect is that information from both of these space- and ground-based monitoring systems is available automatically and in real time. In addition, satellite data from earlier local times, e.g., data monitored from European ground stations, can give precursor information of later North American geomagnetic activity. 24 refs., 2 figs.

  4. Discrete magic angle turning system, apparatus, and process for in situ magnetic resonance spectroscopy and imaging

    DOE Patents [OSTI]

    Hu, Jian Zhi (Richland, WA); Sears, Jr., Jesse A. (Kennewick, WA); Hoyt, David W. (Richland, WA); Wind, Robert A. (Kennewick, WA)

    2009-05-19T23:59:59.000Z

    Described are a "Discrete Magic Angle Turning" (DMAT) system, devices, and processes that combine advantages of both magic angle turning (MAT) and magic angle hopping (MAH) suitable, e.g., for in situ magnetic resonance spectroscopy and/or imaging. In an exemplary system, device, and process, samples are rotated in a clockwise direction followed by an anticlockwise direction of exactly the same amount. Rotation proceeds through an angle that is typically greater than about 240 degrees but less than or equal to about 360 degrees at constant speed for a time applicable to the evolution dimension. Back and forth rotation can be synchronized and repeated with a special radio frequency (RF) pulse sequence to produce an isotropic-anisotropic shift 2D correlation spectrum. The design permits tubes to be inserted into the sample container without introducing plumbing interferences, further allowing control over such conditions as temperature, pressure, flow conditions, and feed compositions, thus permitting true in-situ investigations to be carried out.

  5. Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced by intracluster charge-transfer

    SciTech Connect (OSTI)

    Yandell, Margaret A.; King, Sarah B. [Department of Chemistry, University of California, Berkeley, California 94720 (United States)] [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Neumark, Daniel M., E-mail: dneumark@berkeley.edu [Department of Chemistry, University of California, Berkeley, California 94720 (United States); Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720 (United States)

    2014-05-14T23:59:59.000Z

    Decay dynamics of nascent dipole bound states of acetonitrile and nitromethane are examined using time-resolved photoelectron imaging of iodide-acetonitrile (I{sup ?}·CH{sub 3}CN) and iodide-nitromethane (I{sup ?}·CH{sub 3}NO{sub 2}) complexes. Dipole-bound anions are created by UV-initiated electron transfer to the molecule of interest from the associated iodide ion at energies just below the vertical detachment energy of the halide-molecule complex. The acetonitrile anion is observed to decay biexponentially with time constants in the range of 4–900 ps. In contrast, the dipole bound state of nitromethane decays rapidly over 400 fs to form the valence bound anion. The nitromethane valence anion species then decays biexponentially with time constants of 2 ps and 1200 ps. The biexponential decay dynamics in acetonitrile are interpreted as iodine atom loss and autodetachment from the excited dipole-bound anion, followed by slower autodetachment of the relaxed metastable ion, while the dynamics of the nitromethane system suggest that a dipole-bound anion to valence anion transition proceeds via intramolecular vibrational energy redistribution to nitro group modes in the vicinity of the iodine atom.

  6. Comments to support the Dipole Dynamical Model (DDM) of Ball Lightning (BL)

    E-Print Network [OSTI]

    V. N. Soshnikov

    2015-02-01T23:59:59.000Z

    I present estimates to justify previously proposed by me heuristic Dipole Dynamical Model (DDM) of Ball Lightning (BL). The movement and energy supplying to the dipole BL are due to the atmospheric electric field. Crucial for the detailed analysis of BL is using the new relation of balance of the force of atmospheric electric field (per unit mass of electron cloud) and dipole forces electrons-ions within BL dipole (per unit mass of BL) as the first necessary condition for the existance of BL as an integer. This model is unique because, unlike existing static models, fundamental condition for the existence of Ball Lightning is its forward motion. The virial theorem limiting BL power does not apply to BL which is not closed system like the Sun or Galaxy systems and is strongly dependent part of the infinitely extended in time and space large system. Stability of BL is due to two free parameters with the fundamental role of thermodynamic non-equilibrium, ionization, recombination and translational movement with energy loss by radiation and also excess volumetric positive charge. Polarization degree of BL plasma is characterized by polarizability factor {\\gamma}. An example is presented of calculating the stability of option BL. There is also a possible connection of stability BL with statistical distributions of the atmospheric electric field in time and space. Destruction of BL can also occur due to arising kinematical instability at its accelerating (or decelerating) movement. Maximal energy density in BL DDM does not exceed the value Espec<(10(8) - 10(9)) J/m(3). Resulting indefinitely long BL lifetime is also discussed.

  7. Comments to support the Dipole Dynamical Model (DDM) of Ball Lightning (BL)

    E-Print Network [OSTI]

    V. N. Soshnikov

    2015-06-22T23:59:59.000Z

    I present estimates to justify previously proposed by me heuristic Dipole Dynamical Model (DDM) of Ball Lightning (BL). The movement and energy supplying to the dipole BL are due to the atmospheric electric field. Crucial for the detailed analysis of BL is using the new relation of balance of the force of atmospheric electric field (per unit mass of electron cloud) and dipole forces electrons-ions within BL dipole (per unit mass of BL) as the first necessary condition for the existance of BL as an integer. This model is unique because, unlike existing static models, fundamental condition for the existence of Ball Lightning is its forward motion. The virial theorem limiting BL power does not apply to BL which is not closed system like the Sun or Galaxy systems and is strongly dependent part of the infinitely extended in time and space large system. Stability of BL is due to two free parameters with the fundamental role of thermodynamic non-equilibrium, ionization, recombination and translational movement with energy loss by radiation and also excess volumetric positive charge. Stability of BL is not related to the presence of any external shells. Polarization degree of BL plasma is characterized by polarizability factor {\\gamma}. An example is presented of calculating the stability of option BL. There is also a possible connection of stability BL with statistical distributions of the atmospheric electric field in time and space. Destruction of BL can also occur due to arising kinematical instability at its accelerating (or decelerating) movement. Maximal energy density in BL DDM does not exceed the value Espec<(10(8) - 10(9)) J/m(3). Resulting indefinitely long BL lifetime is also discussed.

  8. Nucleon tensor charges and electric dipole moments

    E-Print Network [OSTI]

    Mario Pitschmann; Chien-Yeah Seng; Craig D. Roberts; Sebastian M. Schmidt

    2014-12-22T23:59:59.000Z

    A symmetry-preserving Dyson-Schwinger equation treatment of a vector-vector contact interaction is used to compute dressed-quark-core contributions to the nucleon $\\sigma$-term and tensor charges. The latter enable one to directly determine the effect of dressed-quark electric dipole moments (EDMs) on neutron and proton EDMs. The presence of strong scalar and axial-vector diquark correlations within ground-state baryons is a prediction of this approach. These correlations are active participants in all scattering events and thereby modify the contribution of the singly-represented valence-quark relative to that of the doubly-represented quark. Regarding the proton $\\sigma$-term and that part of the proton mass which owes to explicit chiral symmetry breaking, with a realistic $d$-$u$ mass splitting the singly-represented $d$-quark contributes 37% more than the doubly-represented $u$-quark; and in connection with the proton's tensor charges, $\\delta_T u$, $\\delta_T d$, the ratio $\\delta_T d/\\delta_T u$ is 18% larger than anticipated from simple quark models. Of particular note, the size of $\\delta_T u$ is a sensitive measure of the strength of dynamical chiral symmetry breaking; and $\\delta_T d$ measures the amount of axial-vector diquark correlation within the proton, vanishing if such correlations are absent.

  9. Confronting Higgcision with Electric Dipole Moments

    E-Print Network [OSTI]

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

    2014-06-24T23:59:59.000Z

    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.

  10. Accumulation Rate of Bound States of Dipoles in Graphene

    E-Print Network [OSTI]

    Simone Rademacher; Heinz Siedentop

    2015-07-08T23:59:59.000Z

    We prove that the bound state energies of the two-dimensional massive Dirac operator with dipole type potentials accumulate with exponentials rate at the band edge. In fact we prove a corresponding formula of De Martino et al (2014)

  11. Measured radiation patterns of the scale model dipole tool

    E-Print Network [OSTI]

    Lu, Rongrong

    2003-01-01T23:59:59.000Z

    The sound field of finite dipole acoustic transducers in a steel tool was investigated and their horizontal by measuring their vertical radiation patterns in water at two different frequencies. Measurements were also made ...

  12. Radiation and evolution of small relativistic dipole in QED

    E-Print Network [OSTI]

    B. Blok

    2003-05-26T23:59:59.000Z

    We study in the quasiclassical approximation the radiation reaction and its influence on the space-time evolution for the small relativistic dipole moving in a constant external electromagnetic field in QED.

  13. Dipoles in Graphene Have Infinitely Many Bound States

    E-Print Network [OSTI]

    Jean-Claude Cuenin; Heinz Siedentop

    2014-03-27T23:59:59.000Z

    We show that in graphene charge distributions with non-vanishing dipole moment have infinitely many bound states. The corresponding eigenvalues accumulate at the edges of the gap faster than any power.

  14. The Pygmy Dipole Resonance status and new developments

    E-Print Network [OSTI]

    Zilges, Andreas

    : #12;Giant Dipole Resonance (GDR) Phys. Rev. 71 (1947) 3 1947: Photo-Fission in Uranium #12;Giant to neutron skin, neutron star radius · Slope of symmetry energy in EoS · Impact on nucleosynthesis S. Goriely

  15. Multiple frequency electron cyclotron heating for the Levitated Dipole Experiment

    E-Print Network [OSTI]

    Mahar, Scott B

    2005-01-01T23:59:59.000Z

    The use of multiple frequencies of electron cyclotron resonance heating (ECRH) in the Levitated Dipole Experiment (LDX) is an important tool that will tailor the plasma profiles. Initial LDX plasmas have been created using ...

  16. Application Of Gravity And Deep Dipole Geoelectrics In The Volcanic...

    Open Energy Info (EERE)

    Of Mt Etna (Sicily) Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Application Of Gravity And Deep Dipole Geoelectrics In The Volcanic Area Of...

  17. Superconductivity, magnetic order, and quadrupolar order in the filled skutterudite system Pr 1 ? x Nd x Os 4 Sb 12

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

    Ho, P.-C.; Yanagisawa, T.; Yuhasz, W. M.; Dooraghi, A. A.; Robinson, C. C.; Butch, N. P.; Baumbach, R. E.; Maple, M. B.

    2011-01-01T23:59:59.000Z

    Superconductivity, magnetic order, and the high field ordered phase have been investigated in the filled skutterudite system Pr1-xNdxOs?Sb?? as a function of composition x in magnetic fields up to 9 T and at temperatures between 50 mK and 10 K. Electrical resistivity measurements indicate that the high field ordered phase, which has been identified with antiferroquadruoplar order, persists to x ~ 0.5. The superconducting critical temperature Tc of PrOs?Sb?? is depressed linearly with Nd concentration to x ~ 0.55, whereas the Curie temperature TFM of NdOs?Sb?? is depressed linearly with Pr composition to (1-x) ~ 0.45. In the superconducting region, the upper critical field Hc2(x,0) is depressed quadratically with x in the range 0 c2(x,0) appears to be a result of pair breaking caused by the applied magnetic field and the exchange field associated with the polarization of the Nd magnetic moments in the superconducting state. From magnetic susceptibility measurements, the correlations between the Nd moments in the superconducting state appear to change from ferromagnetic in the range 0.3 ? x ? 0.6 to antiferromagnetic in the range 0 c2(x,0) with x.

  18. CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

    E-Print Network [OSTI]

    1979-01-01T23:59:59.000Z

    CERN 6 Tesla superconducting persistent dipole/Filming an experiment/Synchrotron radiation from protons

  19. The Intra-Americas Sea springtime surface temperature anomaly dipole as fingerprint of remote influences

    E-Print Network [OSTI]

    Wang, Chunzai

    The Intra-Americas Sea springtime surface temperature anomaly dipole as fingerprint of remote anomaly dipole we find that the dipole forms mostly in response to changes in the air-sea heat fluxes. The changes in shortwave radiation also contribute to the dipole of net air-sea heat flux. The changes

  20. SYMMETRY CHANGES AND DIPOLE ORDERINGS IN THE SMECTIC A TO C PHASE TRANSITIONS OF SECOND ORDER

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    exhibiting dipole ordering. A simple argument based on a mean-field calculation of the dipole- dipole energy phase. Recently the interest in this question was renewed by the first clear-cut evidence of dipole ordering in liquid crystals has not been studied from a general Article published online by EDP Sciences

  1. Reduced electron temperature in a magnetized inductively-coupled plasma with internal coil

    SciTech Connect (OSTI)

    Arancibia Monreal, J.; Chabert, P. [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France)] [LPP, CNRS, Ecole Polytechnique, UPMC, Paris XI, 91128 Palaiseau (France); Godyak, V. [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States) [RF Plasma Consulting, Brookline, Massachusetts 02446 (United States); Michigan Institute for Plasma Science and Engineering, University of Michigan, Ann Arbor, Michigan 48109 (United States)

    2013-10-15T23:59:59.000Z

    The effect of magnetic filtering on the electron energy distribution function is studied in an inductive discharge with internal coil coupling. The coil is placed inside the plasma and driven by a low-frequency power supply (5.8 MHz) which leads to a very high power transfer efficiency. A permanent dipole magnet may be placed inside the internal coil to produce a static magnetic field around 100 Gauss. The coil and the matching system are designed to minimize the capacitive coupling to the plasma. Capacitive coupling is quantified by measuring the radiofrequency (rf) plasma potential with a capacitive probe. Without the permanent magnet, the rf plasma potential is significantly smaller than the electron temperature. When the magnet is present, the rf plasma potential increases. The electron energy distribution function is measured as a function of space with and without the permanent magnet. When the magnet is present, electrons are cooled down to low temperature in the downstream region. This region of low electron temperature may be useful for plasma processing applications, as well as for efficient negative ion production.

  2. A study of coupled dipole antennas in echelon

    E-Print Network [OSTI]

    Patwari, Abdul Matin

    1961-01-01T23:59:59.000Z

    OF SCIENCE January 1961 Major Subject: Electrical Engineering A STUDY OF COUPLED DIPOLE ANTENNAS IN ECHELON A THESIS by Abdul Matin Patwari Approved as to style and content by: Chairman of the Committee 8, Head oi' the Department January 1961...A STUDY OF COUPLED DIPOLE ANTENNAS IN ECHELON A THESIS by Abdul Matin Patwari Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements I' or the degree of MASTER...

  3. $?^*p$ cross section from the dipole model in momentum space

    E-Print Network [OSTI]

    J. T. de Santana Amaral; M. A. Betemps; M. B. Gay Ducati; G. Soyez

    2006-12-07T23:59:59.000Z

    We reproduce the DIS measurements of the proton structure function at high energy from the dipole model in momentum space. To model the dipole-proton forward scattering amplitude, we use the knowledge of asymptotic solutions of the Balitsky-Kovchegov equation, describing high-energy QCD in the presence of saturation effects. We compare our results with the previous analysis in coordinate space and discuss possible extensions of our approach.

  4. NLO Evolution of Color Dipoles in N = 4 SYM

    E-Print Network [OSTI]

    Giovanni A. Chirilli

    2008-11-21T23:59:59.000Z

    The small-$x_B$ deep inelastic scattering in the saturation region is governed by the non-linear evolution of Wilson-line operators. In the leading logarithmic approximation it is given by the BK equation for the evolution of color dipoles. I discuss recent calculation of the next-to-leading order evolution of color dipoles in QCD and ${\\cal N}=4$ SYM.

  5. Magnetic properties of nanomagnetic and biomagnetic systems analyzed using cantilever magnetometry

    E-Print Network [OSTI]

    Aste, Andreas

    and also for the rare earth elements Gd, Dy and Tb at various temperatures. In addition, the magnetic, such as that of Brown's paradox [5]. Micromechanical cantilevers used in atomic force microscopy [6] (AFM) are highly sensitive force and torque sensors and therefore ideal tools for detecting magnetic properties of small

  6. Abstract--Linear electrical loading system (LELS) driven by electrical cylinder with permanent magnet synchronous

    E-Print Network [OSTI]

    Yao, Bin

    magnet synchronous motor (PMSM) offers several advantages of high transmission efficiency and high cylinder driven by permanent magnet synchronous motor (PMSM). Though direct-drive linear motors has some to direct-drive linear motor, the solution of electrical cylinder with PMSM has larger output force

  7. Nuclear magnetic resonance wide-line study of hydrogen in the yttrium-yttrium dihydride system

    SciTech Connect (OSTI)

    Anderson, D.L.

    1980-03-01T23:59:59.000Z

    The /sup 1/H nuclear magnetic resonance was studied in the yttrium-hydrogen system YH/sub x/ in the composition range 0.20 less than or equal to x less than or equal to 1.98 and temperature range 77 K less than or equal to T less than or equal to 490/sup 0/K. Both ..cap alpha..- and ..beta..-phases of YH/sub x/ were investigated in polycrystalline (powdered) specimens. Rigid lattice proton resonance second moments were obtained for both ..cap alpha..- and ..beta..-phase samples. Analysis of the second moment for ..cap alpha..-YH/sub x/ (..cap alpha..-phase) indicates that the hydrogen resides in both the tetrahedral and octahedral interstitial sites of the hcp Y lattice. Second moment values for ..beta..-YH/sub x/ (..beta..-phase) indicate that a sizeable fraction of the octahedral interstitial sites in the fcc yttrium metal lattice are occupied by hydrogen, while a nonnegligible fraction of the tetrahedral interstitial sites are vacant. For example, in YH/sub 1.98/, 28% of the octahedral sites are occupied, while 15% of the tetrahedral sites are vacant. The results for ..beta..-YH/sub x/ also indicate that as the H concentration increases, the probability of H occupation of octahedral sites increases.

  8. A Study to Develop an Industrial-Scale, Computer-Controlled High Magnetic Field Processing (HMFP) System to Assist in Commercializing the Novel, Enabling HMFP Manufacturing Technology

    SciTech Connect (OSTI)

    Ludtka, Gail Mackiewicz- [ORNL; Chourey, Aashish [American Magnetics Inc.

    2010-08-01T23:59:59.000Z

    As the original magnet designer and manufacturer of ORNL s 9T, 5-inch ID bore magnet, American Magnetics Inc. (AMI) has collaborated with ORNL s Materials Processing Group s and this partnership has been instrumental in the development of our unique thermo-magnetic facilities and expertise. Consequently, AMI and ORNL have realized that the commercial implementation of the High Magnetic Field Processing (HMFP) technology will require the evolution of robust, automated superconducting (SC) magnet systems that will be cost-effective and easy to operate in an industrial environment. The goal of this project and CRADA is to significantly expedite the timeline for implementing this revolutionary and pervasive cross-cutting technology for future US produced industrial components. The successful completion of this project is anticipated to significantly assist in the timely commercialization and licensing of our HMFP intellectual property for a broad spectrum of industries; and to open up a new market for AMI. One notable outcome of this project is that the ThermoMagnetic Processing Technology WON a prestigious 2009 R&D 100 Awards. This award acknowledges and recognizes our TMP Technology as one of the top 100 innovative US technologies in 2009. By successfully establishing the design requirements for a commercial scale magnetic processing system, this project effort has accomplished a key first step in facilitating the building and demonstration of a superconducting magnetic processing coil, enabling the transition of the High Magnetic Field Processing Technology beyond a laboratory novelty into a commercially viable and industrially scalable Manufacturing Technology.

  9. Geophysical Fault Mapping Using the Magnetic Method at Hickory Sandstone Aquifer, Llano Uplift, Texas

    E-Print Network [OSTI]

    Pereira, Antonio Do Nascimento

    2013-04-05T23:59:59.000Z

    .1 Governing equations & basic theory . . . . . . . . . . . . . . . . . . . 8 2.1.1 The main eld . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 2.1.2 Theory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14 2.2 Magnetic petrology... possesses a volume V and magnetization J . A fault or a lithologic contact can be approximated to a line of point dipoles. 15 2.2 Magnetic petrology The concept of magnetic petrology [Clark, 1997] integrates conventional and rock magnetism petrology...

  10. U-70 Proton Synchrotron Extracted Beam Lines Control System Modernization

    E-Print Network [OSTI]

    V. Alferov; Y. Bordanovski; S. Klimov; V. Ilukin; V. Kuznetsov; O. Radin; A. Shalunov; A. Sytin; P. Vetrov; V. Yaryguine; V. Zapolsky; V. Zarucheisky

    2001-11-07T23:59:59.000Z

    A 70 GeV Proton Synchrotron Extracted Beam Lines Control System is described. About 130 Magnet Dipoles and Quadrupoles, 20 Correction Magnets, 50 Beam Collimators, BPM equipment spread over 1 Km have to be controlled. The old System was based on the PDP-11/40 and LSI-11 compatible computers and the MIL 1553 STD as a Field Bus. It successfully operated about 15 years. A new system includes home made Equipment Controllers based on I 8051 Processors, CAN Field Bus, FECs, Servers, Consoles connected by Ethernet. On the first stage of modernization PDPs and LSIs are replaced with PCs connected by Ethernet. Equipment controllers are being successfully tested in the Collimators and Corrector Magnets Controls during a run.

  11. MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM , M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone,

    E-Print Network [OSTI]

    Gupta, Ramesh

    MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R. Gupta# , M. Anerella, W of the main solenoid are listed in Table 1. The design was optimized to use many existing magnet components. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A. Pikin, and P. Wanderer

  12. Modeling and Vibration Control with a Nanopositioning Magnetic-Levitation System

    E-Print Network [OSTI]

    Kim, Young Ha

    2012-02-14T23:59:59.000Z

    This dissertation demonstrates that a magnetic-levitation (maglev) stage has the capabilities to control movements and reject vibration simultaneously. The mathematical model and vibration control scheme with a 6-degree-of-freedom (6-DOF) maglev...

  13. Eight-Channel Head Array and Control System for Parallel Transmit/Receive Magnetic Resonance Imaging

    E-Print Network [OSTI]

    Moody, Katherine

    2014-08-11T23:59:59.000Z

    Interest in magnetic resonance imaging (MRI) at high fields strengths (3 Tesla and above) is driven by the associated improvements in signal-to-noise ratio and spectral resolution. In practice, however, technical challenges prevent these benefits...

  14. Analysis and control of a cellular converter system with stochastic ripple cancellation and minimal magnetics

    E-Print Network [OSTI]

    Perreault, David J.

    A parallel converter architecture based on the resonant pole inverter (RPI) topology is presented. It is shown that this architecture minimizes the output magnetics required for current sharing. A new current control scheme ...

  15. Superconducting magnets for SCRF cryomodules at front end of linear accelerators

    SciTech Connect (OSTI)

    Kashikhin, V.S.; Andreev, N.; Orlov, Y.; Orris, D.F.; Tartaglia, M.A.; /Fermilab

    2010-05-01T23:59:59.000Z

    Linear accelerators based on a superconducting technology need various superconducting magnets mounted inside SCRF Cryomodules. Relatively weak iron-dominated magnets are installed at the front end of linear accelerators. The focusing quadrupoles have integrated gradients in the range of 1-4 T, and apertures in the range 35-90 mm. Superconducting dipole correctors and quadrupoles were designed at Fermilab for various projects. In this paper these magnet designs, and test results of a fabricated dipole corrector, are presented. Also briefly discussed are magnetic and mechanical designs, quench protection, cooling, fabrication, and assembly into cryomodule.

  16. Open-loop correction for an eddy current dominated beam-switching magnet

    SciTech Connect (OSTI)

    Koseki, K., E-mail: kunio.koseki@kek.jp; Nakayama, H.; Tawada, M. [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)] [High Energy Accelerator Research Organization, 1-1 Oho, Tsukuba, Ibaraki 305-0801 (Japan)

    2014-04-15T23:59:59.000Z

    A beam-switching magnet and the pulsed power supply it requires have been developed for the Japan Proton Accelerator Research Complex. To switch bunched proton beams, the dipole magnetic field must reach its maximum value within 40 ms. In addition, the field flatness should be less than 5?×?10{sup ?4} to guide each bunched beam to the designed orbit. From a magnetic field measurement by using a long search coil, it was found that an eddy current in the thick endplates and laminated core disturbs the rise of the magnetic field. The eddy current also deteriorates the field flatness over the required flat-top period. The measured field flatness was 5?×?10{sup ?3}. By using a double-exponential equation to approximate the measured magnetic field, a compensation pattern for the eddy current was calculated. The integrated magnetic field was measured while using the newly developed open-loop compensation system. A field flatness of less than 5?×?10{sup ?4}, which is an acceptable value, was achieved.

  17. 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems

    SciTech Connect (OSTI)

    Berk, Herbert L.; Breizman, Boris N.

    2014-02-21T23:59:59.000Z

    The 12th IAEA Technical Meeting on Energetic Particles in Magnetic Confinement Systems took place in Austin, Texas (7–11 September 2011). This meeting was organized jointly with the 5th IAEA Technical Meeting on Theory of Plasma Instabilities (5–7 September 2011). The two meetings shared one day (7 September 2011) with presentations relevant to both groups. Some of the work reported at these meetings was then published in a special issue of Nuclear Fusion [Nucl. Fusion 52 (2012)]. Summaries of the Energetic Particle Conference presentations were given by Kazuo Toi and Boris Breizman. They respectively discussed the experimental and theoretical progress presented at the meeting. Highlights of this meeting include the tremendous progress that has been achieved in the development of diagnostics that enables the ‘viewing’ of internal fluctuations and allows comparison with theoretical predictions, as demonstrated, for example, in the talks of P. Lauber and M. Osakabe. The need and development of hardened diagnostics in the severe radiation environment, such as those that will exist in ITER, was discussed in the talks of V. Kiptily and V.A. Kazakhov. In theoretical studies, much of the effort is focused on nonlinear phenomena. For example, detailed comparison of theory and experiment on D-III-D on the n = 0 geodesic mode was reported in separate papers by R. Nazikian and G. Fu. A large number of theoretical papers were presented on wave chirping including a paper by B.N. Breizman, which notes that wave chirping from a single frequency may emanate continuously once marginal stability conditions have been established. Another area of wide interest was the detailed study of alpha orbits in a burning plasma, where losses can come from symmetry breaking due to finite coil number or magnetic field imperfections introduced by diagnostic or test modules. An important area of development, covered by M.A. Hole and D.A. Spong, is concerned with the self-consistent treatment of the induced fields that accounts for toroidally asymmetric MHD response. In addition, a significant number of studies focused on understanding nonlinear behavior by means of computer simulation of energetic particle driven instability. An under-represented area of investigation was the study of electron runaway formation during major tokamak disruptions. It was noted in an overview by S. Putvinski that electron energies in the 10–20 MeV range is to be expected during projected major disruptions in ITER and that reliable methods for mitigation of the runaway process needs to be developed. Significant recent work in the field of the disruption induced electron runaway, which was reported by J. Riemann, had been submitted to Physics of Plasmas [3]. Overall it is clear that reliable mitigation of electron runaway is an extremely important topic that is in need of better understanding and solutions.

  18. Out-of-Plane Computed-Tomography-Guided Biopsy Using a Magnetic-Field-Based Navigation System

    SciTech Connect (OSTI)

    Wallace, Michael J., E-mail: mwallace@di.mdacc.tmc.edu; Gupta, Sanjay; Hicks, Marshall E. [University of Texas M. D. Anderson Cancer Center, Departments of Diagnostic Radiology, Section of Vascular and Interventional Radiology (United States)

    2006-02-15T23:59:59.000Z

    The purpose of this article is to report our clinical experience with out-of-plane computed-tomography (CT)-guided biopsies using a magnetic-field-based navigation system. Between February 2002 and March 2003, 20 patients underwent CT-guided biopsy in which an adjunct magnetic-field-based navigation system was used to aid an out-of-plane biopsy approach. Eighteen patients had an underlying primary malignancy. All biopsies involved the use of a coaxial needle system in which an outer 18G guide needle was inserted to the lesion using the navigation system and an inner 22G needle was then used to obtain fine-needle aspirates. Complications and technical success were recorded. Target lesions were located in the adrenal gland (n = 7), liver (n = 6), pancreas (n = 3), lung (n = 2), retroperitoneal lymph node (n = 1), and pelvis (n = 1). The mean lesion size (maximum transverse diameter) was 26.5 mm (range: 8-70 mm) and the mean and median cranial-caudal distance, between the transaxial planes of the final needle tip location and the needle insertion site, was 40 mm (range: 18-90 mm). Needle tip positioning was successfully placed within the lesion in all 20 biopsies. A diagnosis of malignancy was obtained in 14 biopsies. Benign diagnoses were encountered in the remaining six biopsies and included a benign adrenal gland (n = 2), fibroelastic tissue (n = 1), hepocytes with steatosis (n = 2) and reactive hepatocytes (n = 1). No complications were encountered. A magnetic-field-based navigation system is an effective adjunct tool for accurate and safe biopsy of lesions that require an out-of-plane CT approach.

  19. Hysteretic magnetoresistance and thermal bistability in a magnetic two-dimensional hole system

    E-Print Network [OSTI]

    Wurstbauer, Ursula; Weiss, Dieter; Dietl, Tomasz; Wegscheider, Werner; 10.1038/nphys1782

    2011-01-01T23:59:59.000Z

    Colossal negative magnetoresistance and the associated field-induced insulator-to-metal transition, the most characteristic features of magnetic semiconductors, are observed in n-type rare earth oxides and chalcogenides, p-type manganites, n-type and p-type diluted magnetic semiconductors (DMS) as well as in quantum wells of n-type DMS. Here, we report on magnetostransport studies of Mn modulation-doped InAs quantum wells, which reveal a magnetic field driven and bias voltage dependent insulator-to-metal transition with abrupt and hysteretic changes of resistance over several orders of magnitude. These phenomena coexist with the quantised Hall effect in high magnetic fields. We show that the exchange coupling between a hole and the parent Mn acceptor produces a magnetic anisotropy barrier that shifts the spin relaxation time of the bound hole to a 100 s range in compressively strained quantum wells. This bistability of the individual Mn acceptors explains the hysteretic behaviour while opening prospects for i...

  20. SUPERCONDUCTING RF-DIPOLE DEFLECTING AND CRABBING CAVITIES

    SciTech Connect (OSTI)

    Delayen, Jean [ODU, JLAB; De Silva, Paygalage Subashini [ODU, JLAB

    2013-09-01T23:59:59.000Z

    Recent interests in designing compact deflecting and crabbing structures for future accelerators and colliders have initiated the development of novel rf structures. The superconducting rf-dipole cavity is one of the first compact designs with attractive properties such as higher gradients, higher shunt impedance, the absence of lower order modes and widely separated higher order modes. Two rf-dipole designs of 400 MHz and 499 MHz have been designed, fabricated and tested as proof-of-principle designs of compact deflecting and crabbing cavities for the LHC high luminosity upgrade and Jefferson Lab 12 GeV upgrade. The first rf tests have been performed on the rf-dipole geometries at 4.2 K and 2.0 K in a vertical test assembly with excellent results. The cavities have achieved high gradients with high intrinsic quality factors, and multipacting levels were easily processed.

  1. Dipole Excitation With A Paul Ion Trap Mass Spectrometer

    SciTech Connect (OSTI)

    MacAskill, J. A.; Madzunkov, S. M.; Chutjian, A. [Atomic and Molecular Physics Group, Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States)

    2011-06-01T23:59:59.000Z

    Preliminary results are presented for the use of an auxiliary radiofrequency (rf) excitation voltage in combination with a high purity, high voltage rf generator to perform dipole excitation within a high precision Paul ion trap. These results show the effects of the excitation frequency over a continuous frequency range on the resultant mass spectra from the Paul trap with particular emphasis on ion ejection times, ion signal intensity, and peak shapes. Ion ejection times are found to decrease continuously with variations in dipole frequency about several resonant values and show remarkable symmetries. Signal intensities vary in a complex fashion with numerous resonant features and are driven to zero at specific frequency values. Observed intensity variations depict dipole excitations that target ions of all masses as well as individual masses. Substantial increases in mass resolution are obtained with resolving powers for nitrogen increasing from 114 to 325.

  2. Hadron production at LHC in dipole momentum space

    SciTech Connect (OSTI)

    Basso, E. A.; Gay Ducati, M. B. [Instituto de Fisica, Universidade Federal do Rio Grande do Sul, Caixa Postal 15051, 91501-970 - Porto Alegre, RS (Brazil); De Oliveira, E. G. [Instituto de Fisica, Universidade de Sao Paulo, Caixa Postal 66318, 05314-970 Sao Paulo, SP (Brazil)

    2013-03-25T23:59:59.000Z

    The dipole color approach is the framework that considers the quark-antiquark pair scattering off the target. The rapidity evolution of color dipoles is given by the nonlinear Balitsky-Kovchegov (BK) equation, for which analytical solutions are not yet known. A good way to explore the asymptotic BK solutions is through the traveling wave method of QCD, that uses a correspondence between the BK evolution equation in momentum space and reaction-diffusion physics. Using the traveling wave based AGBS model for the dipole amplitude in momentum space, and within the k{sub t}-factorization formalism, we describe the LHC data on single inclusive hadron yield for p-p collisions.

  3. Calculation of geometric phases in electric dipole searches with trapped spin-1/2 particles based on direct solution of the Schrödinger equation

    E-Print Network [OSTI]

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

    2014-05-23T23:59:59.000Z

    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.

  4. Numerical Simulation of Plasma Behavior in a Magnetic Nozzle of a Laser-plasma Driven Nuclear Electric Propulsion System

    SciTech Connect (OSTI)

    Kajimura, Y. [Research Institute for Sustainable Humanosphere (RISH), Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan); Japan Science and Technology Agency (JST), CREST 4-1-8 Hon-chou, Kawaguchi, Saitama 332-0012 (Japan); Matsuda, N.; Hayashida, K.; Maeno, A.; Nakashima, H. [Department of Advanced Energy Engineering Science, Interdisciplinary Graduate school of Engineering Sciences, Kyushu University, Kasugakouen 6-1, Kasuga, Fukuoka 816-580 (Japan)

    2008-12-31T23:59:59.000Z

    Numerical simulations of plasma behavior in a magnetic nozzle of a Laser-Plasma Driven Nuclear Electric Propulsion System are conducted. The propellant is heated and accelerated by the laser and expanded isotropically. The magnetic nozzle is a combination of solenoidal coils and used to collimate and guide the plasma to produce thrust. Simulation calculations by a three-dimensional hybrid code are conducted to examine the plasma behaviors in the nozzle and to estimate the thrust efficiency. We also estimate a fraction ({alpha}) of plasma particles leaking in the forward (spacecraft) direction. By a combination of a few coils, we could decrease {alpha} value without degrading the thrust efficiency. Finally, the shaped propellant is proposed to increase the thrust efficiency.

  5. A Synergy of Novel Experiments, Materials Science, Fundamental Physics, and Superconducting Magnets

    E-Print Network [OSTI]

    Godeke, Arno

    2007-01-01T23:59:59.000Z

    Fundamental Physics Superconducting Magnets Yields: Accuraterecord setting superconducting magnet systems ITER, NMRScience, Fundamental Physics, and Superconducting Magnets

  6. Fast magnetic response in gigahertz-band for columnar-structured Fe nanoparticle assembly

    SciTech Connect (OSTI)

    Ogawa, T., E-mail: tomoyuki@ecei.tohoku.ac.jp; Tate, R. [Department of Electronic Engineering, Graduate School of Engineering, Tohoku University, 6-6-05 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Kura, H. [New Industry Creation Hatchery Center (NICHe), Tohoku University, 6-6-10 Aza-Aoba, Aramaki, Aoba-ku, Sendai 980-8579 (Japan); Oikawa, T.; Hata, K. [Samsung R and D Institute Japan Co., Ltd., 2-7 Sugasawa-cho, Tsurumi-ku, Yokohama 230-0027 (Japan)

    2014-05-07T23:59:59.000Z

    High density Fe-based ferromagnetic nanoparticle (NP) assembly is expected to have unique magnetic properties, such as superferromagnetism and super-spin-glass, different from magnetically isolated NP systems due to strong dipole interactions among the NPs. A high dipole interaction field, H{sub dip}, of ?3.5 kOe can result in a high effective internal field to the magnetic moment of the NP, expecting for ultra-fast magnetic response, that is, a high magnetic resonance frequency, f{sub r}, of ?10 GHz. However, for a simply molded Fe NP assembly, a low f{sub r} was observed due to inhomogeneous distribution of the internal field, implying the necessity of a unidirectional state of H{sub dip} for higher f{sub r}. In this study, we fabricated a columnar Fe NP assembly for realizing the unidirectional state of H{sub dip} by applying our uniquely developed external field-induced agglomeration method for monodispersed Fe NPs (13 nm in average size) as a function of the field (0–30 kOe) and volume fraction of the Fe NPs (0.5%–51%) in a polymer matrix with dimensions of 4 mm × 4 mm × 0.7 mm{sup t}. A columnar-structured Fe NP assembly was successfully achieved along an in-plane direction (defined as the x-axis) under optimized conditions. From static magnetization curves, induced uniaxial magnetic anisotropy was observed according to the shape of the columnar structure of the Fe NP assembly, where easy and hard axes of magnetization were realized along the parallel (x-axis) and normal directions (in-plane y-axis and z-axis in the thickness direction) to the external field during the process, respectively. Interestingly, this fabricated columnar-structured Fe NP assembly exhibited very high f{sub r} in the range from 3 to 11 GHz judging from the complex susceptibility spectra obtained. The f{sub r} values were well-scaled by a modified Snoek's-limit-law using demagnetization factors quantitatively estimated from the static magnetization curves. Thus, shape-induced anisotropy originating from the unidirectional state of H{sub dip} in the columnar structure of the Fe NP assembly plays an important role for high frequency magnetic response in the GHz-band.

  7. Operation of the 30 MJ superconducting magnetic energy storage system in the Bonneville Power Administration Electrical Grid

    SciTech Connect (OSTI)

    Rogers, J.D.; Boenig, H.J.; Schermer, R.I.; Hauer, J.F.

    1984-01-01T23:59:59.000Z

    The 30 MJ superconducting magnetic energy storage (SMES) system was installed in the Bonneville Power Administration (BPA) Tacoma Substation in 1982 to 1983. Operation of the unit since that time has been for over 1200 hours. Specific tests to explore the SMES system's thermal and electrical characteristics and the control functions were conducted. The coil heat load with current modulation was determined. A converter with two 6-pulse bridges interfaces the superconducting coil to the power bus. Equal bridge voltage amplitude and constant reactive power modes of operation of the system were run with computer control of the SCR bridge firing angles. Coil energy dump tests were performed. Electrical grid system response to SMES modulation was observed, and full power SMES modulation was undertaken.

  8. Invisible nanowires with interferencing electric and toroidal dipoles

    E-Print Network [OSTI]

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

    2015-01-01T23:59:59.000Z

    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.

  9. Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced by intracluster charge-transfer

    E-Print Network [OSTI]

    Neumark, Daniel M.

    Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced (2014) Decay dynamics of nascent acetonitrile and nitromethane dipole-bound anions produced 2014; published online 13 May 2014) Decay dynamics of nascent dipole bound states of acetonitrile

  10. Delta-phase manganese gallium on gallium nitride: a magnetically tunable spintronic system

    E-Print Network [OSTI]

    with Mn:Ga ratio between 1:1 to 1.5:1 is grown on wurtzite gallium nitride and scandium nitride substrates. Results suggest that for growth on wurtzite GaN, Ga-polar surface promotes quicker interface formation epitaxially on top of wide band-gap Ga-polar wurtzite GaN(0001), with controllable magnetism by adjusting

  11. JOURNAL OF MICROELECTROMECHANICAL SYSTEMS, VOL. 6, NO. 4, DECEMBER 1997 307 Magnetic and Mechanical Properties

    E-Print Network [OSTI]

    Properties of Micromachined Strontium Ferrite/Polyimide Composites Laure K. Lagorce and Mark G. Allen, Member, IEEE Abstract--In this work, strontium ferrite/polyimide composite thin films are fabricated- oxydianiline/metaphenylene diamine polyimide matrix. Magnetic, mechanical, and processability properties

  12. Fabrication of magnetic microfiltration systems using soft lithography Tao Deng, Mara Prentiss,a)

    E-Print Network [OSTI]

    Prentiss, Mara

    . The combination of microtransfer molding--a soft lithography technique--and electrodeposition generated nickel, Massachusetts 02138 Received 9 August 2001; accepted for publication 9 November 2001 Arrays of nickel posts were field from an external, permanent, neodymium­iron­boron magnet, these nickel posts generated strong

  13. Field quality measurements of a 2-Tesla transmission line magnet

    SciTech Connect (OSTI)

    Velev, G.V.; Foster, W.; Kashikhin, V.; Mazur, P.; Oleck, A.; Piekarz, H.; Schlabach, P.; Sylvester, C.; /Fermilab; Wake, M.; /KEK, Tsukuba

    2005-09-01T23:59:59.000Z

    A prototype 2-Tesla superconducting transmission line magnet for future hadron colliders was designed, built and tested at Fermilab. The 1.5 m long, combined-function gradient-dipole magnet has a vertical pole aperture of 20 mm. To measure the magnetic field quality in such a small magnet aperture, a specialized rotating coil of 15.2 mm diameter, 0.69 m long was fabricated. Using this probe, a program of magnetic field quality measurements was successfully performed. Results of the measurements are presented and discussed.

  14. Noncommutative magnetic moment of charged particles

    SciTech Connect (OSTI)

    Adorno, T. C.; Gitman, D. M. [Instituto de Fisica, Universidade de Sao Paulo (Brazil); Shabad, A. E. [P.N. Lebedev Physics Institute, Moscow (Russian Federation); Vassilevich, D. V. [CMCC - Universidade Federal do ABC, Santo Andre, S.P. (Brazil); Department of Physics, St. Petersburg State University (Russian Federation)

    2011-10-15T23:59:59.000Z

    It has been argued that in noncommutative field theories, the sizes of physical objects cannot be taken smaller than an ''elementary length'' related to noncommutativity parameters. By gauge covariantly extending field equations of noncommutative U(1){sub *} theory to cover the presence of external sources, we find electric and magnetic fields produced by an extended static charge. We find that such a charge, apart from being an ordinary electric monopole, is also a magnetic dipole. By writing off the existing experimental clearance in the value of the lepton magnetic moments for the present effect, we get the bound on noncommutativity at the level of 10{sup 4} TeV.

  15. Observation of suppression of light scattering induced by dipole-dipole interactions in a cold atomic ensemble

    E-Print Network [OSTI]

    J. Pellegrino; R. Bourgain; S. Jennewein; Y. R. P. Sortais; S. D. Jenkins; J. Ruostekoski; A. Browaeys

    2014-10-08T23:59:59.000Z

    We study the emergence of collective scattering in the presence of dipole-dipole interactions when we illuminate a cold cloud of rubidium atoms with a near-resonant and weak intensity laser. The size of the atomic sample is comparable to the wavelength of light. When we gradually increase the atom number from 1 to 450, we observe a broadening of the line, a small red shift and, consistently with these, a strong suppression of the scattered light with respect to the noninteracting atom case. Numerical simulations, which include the internal atomic level structure, agree with the data.

  16. Accurate dipole polarizabilities for water clusters n=2-12 at...

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

    dipole polarizabilities for water clusters n2-12 at the coupled-cluster level of theory and benchmarking of various Accurate dipole polarizabilities for water clusters n2-12 at...

  17. Design and testing of a 13. 75-MW converter for a superconducting magnetic-energy-storage system

    SciTech Connect (OSTI)

    Boenig, H.J.; Turner, R.D.; Neft, C.L.; Sueker, K.H.

    1981-01-01T23:59:59.000Z

    A 30 MJ superconducting magnetic energy storage system will be installed in 1982 in Tacoma, WA, to act as a transmission line stabilizer. Two 6 MVA transformers and a 5.5 kA, + 2.5 kV converter will connect the superconducting coil to the 13.8 kV bus and regulate the power flow between the coil and the three phase system. The design philosophy for the converter including its control and protection system is given in the paper. The converter has been tested with 10% overvoltage at no load, with 10% overcurrent at zero output voltage and with a watercooled resistive load of about 1 MW. These test results show that the converter will meet the expected full load operating conditions.

  18. Performance of a static-anode/flat-panel x-ray fluoroscopy system in a diagnostic strength magnetic field: A truly hybrid x-ray/MR imaging system

    SciTech Connect (OSTI)

    Fahrig, R.; Wen, Z.; Ganguly, A.; DeCrescenzo, G.; Rowlands, J.A.; Stevens, G.M.; Saunders, R.F.; Pelc, N.J. [Department of Radiology, Stanford University, Stanford, California 94305 (United States); Department of Radiology and Department of Physics, Stanford University, Stanford, California 94305 (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States); Sunnybrook and Women's Health Sciences Center and Medical Biophysics, University of Toronto, 2075 Bayview Avenue, Toronto, Ontario M4N 3M5 (Canada); GE Healthcare, Schenectady, Wisconsin (United States); Department of Radiology, Stanford University, Stanford, California 94305 (United States)

    2005-06-15T23:59:59.000Z

    Minimally invasive procedures are increasing in variety and frequency, facilitated by advances in imaging technology. Our hybrid imaging system (GE Apollo{sup TM} flat panel, custom Brand x-ray static anode x-ray tube, GE Lunar high-frequency power supply and 0.5 T Signa SP{sup TM}) provides both x-ray and MR imaging capability to guide complex procedures without requiring motion of the patient between two distant gantries. The performance of the x-ray tube in this closely integrated system was evaluated by modeling and measuring both the response of the filament to an externally applied field and the behavior of the electron beam for field strengths and geometries of interest. The performance of the detector was assessed by measuring the slanted-edge modulation transfer function (MTF) and when placed at zero field and at 0.5 T. Measured resonant frequencies of filaments can be approximated using a modified vibrating beam model, and were at frequencies well below the 25 kHz frequency of our generator for our filament geometry. The amplitude of vibration was not sufficient to cause shorting of the filament during operation within the magnetic field. A simple model of electrons in uniform electric and magnetic fields can be used to estimate the deflection of the electron beam on the anode for the fields of interest between 0.2 and 0.5 T. The MTF measured at the detector and the DQE showed no significant difference inside and outside of the magnetic field. With the proper modifications, an x-ray system can be fully integrated with a MR system, with minimal loss of image quality. Any x-ray tube can be assessed for compatibility when placed at a particular location within the field using the models. We have also concluded that a-Si electronics are robust against magnetic fields. Detailed knowledge of the x-ray system installation is required to provide estimates of system operation.

  19. SOLAR MAGNETIC ACTIVITY CYCLES, CORONAL POTENTIAL FIELD MODELS AND ERUPTION RATES

    SciTech Connect (OSTI)

    Petrie, G. J. D. [National Solar Observatory, Tucson, AZ 85719 (United States)

    2013-05-10T23:59:59.000Z

    We study the evolution of the observed photospheric magnetic field and the modeled global coronal magnetic field during the past 3 1/2 solar activity cycles observed since the mid-1970s. We use synoptic magnetograms and extrapolated potential-field models based on longitudinal full-disk photospheric magnetograms from the National Solar Observatory's three magnetographs at Kitt Peak, the Synoptic Optical Long-term Investigations of the Sun vector spectro-magnetograph, the spectro-magnetograph and the 512-channel magnetograph instruments, and from Stanford University's Wilcox Solar Observatory. The associated multipole field components are used to study the dominant length scales and symmetries of the coronal field. Polar field changes are found to be well correlated with active fields over most of the period studied, except between 2003 and 2006 when the active fields did not produce significant polar field changes. Of the axisymmetric multipoles, only the dipole and octupole follow the poles whereas the higher orders follow the activity cycle. All non-axisymmetric multipole strengths are well correlated with the activity cycle. The tilt of the solar dipole is therefore almost entirely due to active-region fields. The axial dipole and octupole are the largest contributors to the global field except while the polar fields are reversing. This influence of the polar fields extends to modulating eruption rates. According to the Computer Aided CME Tracking, Solar Eruptive Event Detection System, and Nobeyama radioheliograph prominence eruption catalogs, the rate of solar eruptions is found to be systematically higher for active years between 2003 and 2012 than for those between 1997 and 2002. This behavior appears to be connected with the weakness of the late-cycle 23 polar fields as suggested by Luhmann. We see evidence that the process of cycle 24 field reversal is well advanced at both poles.

  20. Nuclear DVCS within the high energy QCD color dipole formalism

    E-Print Network [OSTI]

    M. V. T. Machado

    2009-05-27T23:59:59.000Z

    In this contribution, we present a study of the coherent and incoherent nuclear DVCS process in the small-$x$ regime within the color dipole formalism. Predictions for the nuclear DVCS cross section at photon level in the collider kinematics are presented.

  1. Investigation of Pygmy Dipole Resonances in the Tin Region

    E-Print Network [OSTI]

    N. Tsoneva; H. Lenske

    2008-01-22T23:59:59.000Z

    The evolution of the low-energy electromagnetic dipole response with the neutron excess is investigated along the Sn isotopic chain within an approach incorporating Hartree-Fock-Bogoljubov (HFB) and multi-phonon Quasiparticle-Phonon-Model (QPM) theory. General aspects of the relationship of nuclear skins and dipole sum rules are discussed. Neutron and proton transition densities serve to identify the Pygmy Dipole Resonance (PDR) as a generic mode of excitation. The PDR is distinct from the GDR by its own characteristic pattern given by a mixture of isoscalar and isovector components. Results for the $^{100}$Sn-$^{132}$Sn isotopes and the several N=82 isotones are presented. In the heavy Sn-isotopes the PDR excitations are closely related to the thickness of the neutron skin. Approaching $^{100}$Sn a gradual change from a neutron to a proton skin is found and the character of the PDR is changed correspondingly. A delicate balance between Coulomb and strong interaction effects is found. The fragmentation of the PDR strength in $^{124}$Sn is investigated by multi-phonon calculations. Recent measurements of the dipole response in $^{130,132}$Sn are well reproduced.

  2. Couplings between dipole and quadrupole vibrations in tin isotopes

    E-Print Network [OSTI]

    Cédric Simenel; Philippe Chomaz

    2009-12-11T23:59:59.000Z

    We study the couplings between collective vibrations such as the isovector giant dipole and isoscalar giant quadrupole resonances in tin isotopes in the framework of the time-dependent Hartree-Fock theory with a Skyrme energy density functional. These couplings are a source of anharmonicity in the multiphonon spectrum. In particular, the residual interaction is known to couple the isovector giant dipole resonance with the isoscalar giant quadrupole resonance built on top of it, inducing a nonlinear evolution of the quadrupole moment after a dipole boost. This coupling also affects the dipole motion in a nucleus with a static or dynamical deformation induced by a quadrupole constraint or boost respectively. Three methods associated with these different manifestations of the coupling are proposed to extract the corresponding matrix elements of the residual interaction. Numerical applications of the different methods to 132Sn are in good agreement with each other. Finally, several tin isotopes are considered to investigate the role of isospin and mass number on this coupling. A simple 1/A dependence of the residual matrix elements is found with no noticeable contribution from the isospin. This result is interpreted within the Goldhaber-Teller model.

  3. Mandlung Summation of Dislocation Dipole Energy January 19, 1999

    E-Print Network [OSTI]

    Cai, Wei

    : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 10 3.2 Running MadSum by Command Lines : : : : : : : : : : : : : : : : : : : : : : : : : : 11 1 #12 of dislocation dipoles, as shown in Fig. 1. The dislocation lines are perpendicular to the plane z \\Theta ~ ¸) \\Delta R]; where ~ b 1;2 are the Burgers vectors of the two dislocations, ¸ is the line

  4. A Study to Develop an Industrial-Scale, Computer-Controlled High Magnetic Field Processing (HMFP) System to Assist in Commercializing the Novel, Enabling HMFP Manufacturing Technology

    SciTech Connect (OSTI)

    Lutdka, G. M.; Chourey, A. (American Magnetics, Inc.)

    2010-05-12T23:59:59.000Z

    As the original magnet designer and manufacturer of ORNL’s 9T, 5-inch ID bore magnet, American Magnetics Inc. (AMI) has collaborated with ORNL’s Materials Processing Group’s and this partnership has been instrumental in the development of our unique thermo-magnetic facilities and expertise. Consequently, AMI and ORNL have realized that the commercial implementation of the High Magnetic Field Processing (HMFP) technology will require the evolution of robust, automated superconducting (SC) magnet systems that will be cost-effective and easy to operate in an industrial environment. The goal of this project and CRADA is to significantly expedite the timeline for implementing this revolutionary and pervasive cross-cutting technology for future US produced industrial components. The successful completion of this project is anticipated to significantly assist in the timely commercialization and licensing of our HMFP intellectual property for a broad spectrum of industries; and to open up a new market for AMI. One notable outcome of this project is that the ThermoMagnetic Processing Technology WON a prestigious 2009 R&D 100 Awards. This award acknowledges and recognizes our TMP Technology as one of the top 100 innovative US technologies in 2009. By successfully establishing the design requirements for a commercial scale magnetic processing system, this project effort has accomplished a key first step in facilitating the building and demonstration of a superconducting magnetic processing coil, enabling the transition of the High Magnetic Field Processing Technology beyond a laboratory novelty into a commercially viable and industrially scalable Manufacturing Technology.

  5. Changes made on a 2.7-m long superconducting solenoid magnet cryogenic system that allowed the magnet to be kept cold using 4 K pulse tube coolers

    SciTech Connect (OSTI)

    Green, M. A.; Pan, H. [Lawrence Berkeley Laboratory, Berkeley CA 94720 (United States); Preece, R. M. [STFC Rutherford Appleton Laboratory, Didcot, Oxfordshire (United Kingdom)

    2014-01-29T23:59:59.000Z

    Two 2.7-m long solenoid magnets with a cold mass of 1400 kg were fabricated in between 2007 and 2010. The magnet cryostat outside diameter is ?1.4 meters and the cryostat length is ?2.73 meters. The magnet warm bore is 0.4 meters. The magnet was designed to be cooled using three 1.5 W two-stage coolers. In both magnets, three coolers could not keep the cryostat filled with liquid helium. The temperatures of the shield and the tops of the HTS leads were too warm. A 140 W single stage cooler was added to magnet 2 to cool the HTS leads, the shield and the cold mass support intercepts. When the magnet 2 was retested in 2010, the net cooling at 4.2 K was ?1.5 W with first-stage temperatures of the four coolers at ?42 K. The tops of the HTS leads were <50 K, but the shield and cold mass support intercepts remained too warm. The solenoid cryostat and shield were modified during 2011 and 2012 to reduce the 4.2 K heat load and increase the cooling. This magnet was tested in 2012, with five 1.5 W two-stage coolers and the single stage cooler. The changes made in the magnet are described in this report. As a result of the cryostat and shield changes, and adding 3.0 W of cooling at 4.2 K, the net 4.2 K cooling changed from ?1.6 W to +5.0 W. About half of the change in net cooling to this magnet was due changes that reduced the shield temperature. This report demonstrates the importance of running the shield cold (?40 K) and reducing the heat loads from all sources on both the shield and the cold mass.

  6. Polarization of metallic carbon nanotubes from a model that includes both net charges and dipoles

    E-Print Network [OSTI]

    Mayer, Alexandre

    computational resources. This time issue is especially important in molecular dynamic simulations, in which both a net electric charge and a dipole. Considering net charges in addition to the dipoles enables one by associating with each atom both a net electric charge and a dipole. From a physical point of view, consid

  7. Magnetic infrasound sensor

    DOE Patents [OSTI]

    Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

    2006-11-14T23:59:59.000Z

    A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

  8. THE OPERATION OF A FORCED TWO PHASE COOLING SYSTEM ON A LARGE SUPERCONDUCTING MAGNET

    E-Print Network [OSTI]

    Green, M.A.

    2010-01-01T23:59:59.000Z

    A FORCED TWO PHASE COOLING SYSTEM ON A LARGE SUPERCONDUCTINGOPERATION O A FORCED T O PHASE COOLING SYSTEM F W O A LARGEof a forced two phase cooling system on a two meter diameter

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

    E-Print Network [OSTI]

    Bowen, Ian Reed

    2010-11-23T23:59:59.000Z

    body and secure detector wires. The detector wires were connected to a 12- conductor cable using heat-shrink butt connectors to transmit the signal to the surface. The diffusion stone was connected to an injection line that carried the tracer from...

  10. Magnetic mirror fusion-fission early history and applicability to other systems

    SciTech Connect (OSTI)

    Moir, R

    2009-08-24T23:59:59.000Z

    In the mid 1970s to mid 1980s the mirror program was stuck with a concept, the Standard Mirror that was Q {approx} 1 where Q=P{sub fusion}/P{sub injection}. Heroic efforts were put into hybridizing thinking added energy and fuel sales would make a commercial product. At the same time the tokamak was thought to allow ignition and ultrahigh Q values of 20 or even higher. There was an effort to use neutral beams to drive the tokamak just like the mirror machines were driven in which case the Q value plunged to a few, however this was thought to be achievable decades earlier than the high Q versions. Meanwhile current drive and other features of the tokamak have seen the projected Q values come down to the range of 10. Meanwhile the mirror program got Q enhancement into high gear and various tandem mirrors projected Q values up towards 10 and with advanced features over 10 with axi-symmetric magnets (See R. F. Post papers), however the experimental program is all but non-existent. Meanwhile, the gas dynamic trap mirror system which is present day state-of-the-art can with low risk produce Q of {approx}0.1 useful for a low risk, low cost neutron source for materials development useful for the development of materials for all fusion concepts (see Simonen white paper: 'A Physics-Based Strategy to Develop a Mirror Fusion-Fission Hybrid' and D.D. Ryutov, 'Axisymmetric MHD-stable mirror as a neutron source and a driver for a fusion-fission hybrid'). Many early hybrid designs with multi-disciplinary teams were carried out in great detail for the mirror system with its axi-symmetric blanket modules. It is recognized that most of these designs are adaptable to tokamak or inertial fusion geometry. When Q is low (1 to 2) economics gives a large economic penalty for high recirculating power. These early studies covered the three design types: Power production, fuel production and waste burning. All three had their place but power production fell away because every study showed fusion machines that were extensively studied by multidisciplinary teams came up with power costs much higher than for existing fission plants except in very large sizes (3 GWe). There was lots of work on waste burning - Ted Parrish - comes to mind. However, fuel production along with power production became nearly everyone's goals. First, fast-fission blankets were favored but later to enhance safety, fission-suppressed blankets came into vogue. Both fuel producing and waste burning hybrid studies were terminated with the advent of accidents, high interest rates, rising 'green like' movement and cheap natural gas for power production. For waste burning and fast-fission fuel producing designs, the blanket energy multiplication was about 10 and economics was OK relative to recirculating power for Q over 2. For fission-suppressed fuel producers, where the blanket multiplication is under 2, the Q needed was over 5. In the mirror program we came at this problem by trying to find a product for mirror fusion technology. We hoped we had a product and studied and promoted it. There was no market pull and when the mirror program collapsed in the US, so did both hybrid programs for mirrors and tokamaks and IFE by the mid 1980s. Today, the problem of what to do with wastes that were supposed to be accepted by the government appears to be a high value market pull. It remains to be shown if fusion neutrons can be generated at low enough cost so that economics will not be a showstopper. For burning only the minor actinides, the economics will be the most favorable. Burning the Pu as well will lower the number of fission reactors supported by each burner fusion machine and hurt economics of the system. The fuel-producing role of fusion to fuel fission reactors remains an important possible use of fusion especially in the early stages of fusion development. It is not clear that burning fission wastes in a fusion machine is more appropriate than burning these wastes in specially designed fission machines. Fusion can produce U-233 along with over 2.4%U-232 making the material large

  11. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    1.1 Magnetic Semiconductors . . . . . . . . . . . . . . .Semiconductors . . . . . . . . . . . . . . . . . . . 1.3in Semiconductors . . . . . . . . . . . . . . . . . . 1.3.5

  12. THE NEW VME-BASED SYSTEM FOR MAGNETIC MEASUREMENTS WITH HALL SENSORS

    E-Print Network [OSTI]

    Kozak, Victor R.

    requirements to such systems. Note also, that for controlling the peripheral equipment like power supplies. ELECTRONICS OF HALL-SENSOR MEASURING SYSTEM The Figure 1 demonstrates the structure of measuring system CABLES CANBUS Figure 1: The structure of Hall measuring system. Carriage and its Thermostabilization

  13. Impact of motion along the field direction on geometric-phase-induced false electric dipole moment signals

    E-Print Network [OSTI]

    H. Yan; B. Plaster

    2011-04-07T23:59:59.000Z

    Geometric-phase-induced false electric dipole moment (EDM) signals, resulting from interference between magnetic field gradients and particle motion in electric fields, have been studied extensively in the literature, especially for neutron EDM experiments utilizing stored ultracold neutrons and co-magnetometer atoms. Previous studies have considered particle motion in the transverse plane perpendicular to the direction of the applied electric and magnetic fields. We show, via Monte Carlo studies, that motion along the field direction can impact the magnitude of this false EDM signal if the wall surfaces are rough such that the wall collisions can be modeled as diffuse, with the results dependent on the size of the storage cell's dimension along the field direction.

  14. Apparatus and method for detecting a magnetic anomaly contiguous to remote location by SQUID gradiometer and magnetometer systems

    DOE Patents [OSTI]

    Overton, W.C. Jr.; Steyert, W.A. Jr.

    1981-05-22T23:59:59.000Z

    A superconducting quantum interference device (SQUID) magnetic detection apparatus detects magnetic fields, signals, and anomalies at remote locations. Two remotely rotatable SQUID gradiometers may be housed in a cryogenic environment to search for and locate unambiguously magnetic anomalies. The SQUID magnetic detection apparatus can be used to determine the azimuth of a hydrofracture by first flooding the hydrofracture with a ferrofluid to create an artificial magnetic anomaly therein.

  15. Full-power test of a string of magnets comprising a half-cell of the Superconducting Super Collider

    SciTech Connect (OSTI)

    Burgett, W.; Christianson, M.; Coombes, R. [and others

    1992-10-01T23:59:59.000Z

    In this paper we describe the full-powered operation of a string of industrially-fabricated magnets comprising a half-cell of the Superconducting Super Collider (SSC). The completion of these tests marks the first successful operation of a major SSC subsystem. The five 15-m long dipole magnets in the string had an aperture of 50 mm and the single 5-m long quadrupole aperture was 40 mm. Power and cryogenic connections were made to the string through spool pieces that are prototypes for SSC operations. The string was cooled to cryogenic temperatures in early July, 1992, and power tests were performed at progressively higher currents up to the nominal SSC operating point above 6500 amperes achieved in mid-August. In this paper we report on the electrical and cryogenic performance of the string components and the quench protection system during these initial tests.

  16. Regulation and large motion tracking for active magnetic bearing system using sliding mode control

    E-Print Network [OSTI]

    Sun, Guangyoung

    1999-01-01T23:59:59.000Z

    tracking of the nonlinear rotor AMB system. For the regulation of rotor, the vertical rotor AMB system with the imbalance disturbance due to the eccentricity of mass is considered for cylindrical and conical mode initial conditions. For the large motion...

  17. Near-field Mapping System to Scan in Time Domain the Magnetic Emissions of Integrated Circuits

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    low amplitude and need to be amplified. This is achieved, as shown figure 1, by a low noise 63db of instructions. Application of this measurement system is given to an industrial chip designed with a 180nm CMOS a low cost near-field mapping system. This system scans automatically and dynamically, in the time

  18. Dipole polarizability of 120Sn and nuclear energy density functionals

    E-Print Network [OSTI]

    Hashimoto, T; Reinhard, P -G; Tamii, A; von Neumann-Cosel, P; Adachi, T; Aoi, N; Bertulani, C A; Fujita, H; Fujita, Y; Ganio?lu, E; Hatanaka, K; Iwamoto, C; Kawabata, T; Khai, N T; Krugmann, A; Martin, D; Matsubara, H; Miki, K; 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; Süsoy, G; Thies, J H; Suzuki, T; Yosoi, M; Zenihiro, J

    2015-01-01T23:59:59.000Z

    The electric dipole strength distribution in 120Sn between 5 and 22 MeV has been determined at RCNP Osaka from a polarization transfer analysis of proton inelastic scattering at E_0 = 295 MeV and forward angles including 0{\\deg}. Combined with photoabsorption data an electric dipole polarizability alpha_D(120Sn) = 8.93(36) fm^3 is extracted. The correlation of this value with alpha_D for 208Pb serves as a test of energy density functionals (EDFs). The majority of models based on Skyrme interactions can describe the data while relativistic approaches fail. The accuracy of the experimental results provides important constraints on the static isovector properties of EDFs used to predict symmetry energy parameters and the neutron skin thickness of nuclei.

  19. Isoscalar and Isovector Splitting of Pygmy Dipole Structures

    SciTech Connect (OSTI)

    Paar, N.; Vretenar, D. [Physics Department, Faculty of Science, University of Zagreb (Croatia); Niu, Y. F. [Physics Department, Faculty of Science, University of Zagreb (Croatia); State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); Meng, J. [State Key Laboratory for Nuclear Physics and Technology, School of Physics, Peking University, Beijing 100871 (China); School of Physics and Nuclear Energy, Beihang University, Beijing 100083 (China)

    2009-07-17T23:59:59.000Z

    The electric-dipole response of {sup 140}Ce is investigated using the fully consistent relativistic quasiparticle random phase approximation. By analyzing the isospin structure of the E1 response, it is shown that the low-energy (pygmy) strength separates into two segments with different isospin character. The more pronounced pygmy structure at lower energy is composed of predominantly isoscalar states with surface-peaked transition densities. At somewhat higher energy the calculated E1 strength is primarily of isovector character, as expected for the low-energy tail of the giant dipole resonance. The results are in qualitative agreement with those obtained in recent (gamma, gamma{sup '}) and (alpha, alpha{sup '}gamma) experiments, and provide a simple explanation for the splitting of low-energy E1 strength into two groups of states with different isospin structure and radial dependence of the corresponding transition densities.

  20. A High Field Magnet Design for A Future Hadron Collider==== R. Gupta, K. Chow, D. Dietderich, S. Gourlay, G. Millos, A. McInturff, R. Scanlan

    E-Print Network [OSTI]

    Gupta, Ramesh

    A High Field Magnet Design for A Future Hadron Collider==== R. Gupta, K. Chow, D. Dietderich, S the completion of LHC. This paper presents a high field magnet design option based on Nb3Sn technology. A preliminary magnetic and mechanical design of a 14-16 T, 2-in-1 dipole based on the "common coil design

  1. A Common Coil Magnet for Testing High Field Superconductors* , J.P. Cozzolino, M.A. Harrison, W.B. Sampson, P.J. Wanderer

    E-Print Network [OSTI]

    Gupta, Ramesh

    . The performance of the magnet is summarized along with test results from insert coils wound from N3 Sn ribbon racetrack shaped coils readily wound from high aspect ratio conductor. In this geometry the magnet has two coil magnet. The turns on the right form one half of the upper and lower dipoles, but are part

  2. Selection Tests of MnZn and NiZn Ferrites for Mu2e 300 kHz and 5.1 MHz AC Dipoles

    SciTech Connect (OSTI)

    Bourkland, K.; Elementi, L.; Feher, S.; Harding, D.J.; Kashikhin, V.S.; Makarov, A.; Pfeffer, H.; Velev, G.V.; /Fermilab; Mulushev, E.; /Institute of Automatics and Electrometry; Iedmeska, I.; /Moscow, MIPT; Venturini, M.; /Pisa U.

    2011-09-09T23:59:59.000Z

    Mu2e, a charged lepton flavor violation (CLFV) experiment is planned to start at Fermilab late in this decade. The proposed experiment will search for neutrinoless muon to electron conversions with unprecedented sensitivity, better than 6 x 10{sup -17 }at 90% CL. To achieve this sensitivity the incoming proton beam must be highly suppressed during the window for detecting the muon decays. The current proposal for beam extinction is based on a collimator design with two dipoles running at {approx}300 kHz and 5.1 MHz and synchronized to the proton bunch spacing. The appropriate choice of ferrite material for the magnet yoke is a critical step in the overall design of the dipoles and their reliable operation at such high frequencies over the life of the experiment. This choice, based on a series of the thermal and magnetic measurements of the ferrite samples, is discussed in the paper. Additionally, the first results from the testing at 300 kHz of a prototype AC dipole are presented.

  3. The DC field components of horizontal and vertical electric dipole sources immersed in three-layered stratified media

    E-Print Network [OSTI]

    Boyer, Edmond

    for the solution in the case of horizontal electric dipole (HED) radiation source and the single-component HertzThe DC field components of horizontal and vertical electric dipole sources immersed in three- ponents of the static (DC) fields of horizontal electric dipoles ( HEDs) and vertical electric dipoles

  4. First Results of the LCLS Laser-Heater System

    SciTech Connect (OSTI)

    Emma, P; Boyce, R.F.; Brachmann, A.; Carr, R.; Decker, F.-J.; Ding, Y.; Dowell, D.; Edstrom, S.; Frisch, J.; Gilevich, S.; Hays, G.; Hering, Ph.; Huang, Z.; Iverson, R.; Levashov, Y.; Loos, H.; Miahnahri, A.; Nuhn, H.-D.; Poling, B.; Ratner, D.; Spampinati, S.; /SLAC

    2011-12-16T23:59:59.000Z

    The Linac Coherent Light Source (LCLS) is an x-ray Free-Electron Laser (FEL) project that has just achieved its first lasing at 1.5 {angstrom} radiation wavelength. The very bright electron beam required to drive this FEL is susceptible to a microbunching instability in the magnetic bunch compressors that may increase the slice energy spread beyond the FEL tolerance. To control the slice energy spread and to suppress the microbunching instability, a laser heater (LH) system is installed in the LCLS injector area at 135 MeV, right before the RF deflector that is used for the time-resolved electron diagnostics. This unique component is used to add a small level of intrinsic energy spread to the electron beam in order to Landau damp the microbunching instability before it potentially breaks up the high brightness electron beam. The system was fully installed and tested in the fall of 2008, and effects of heating on the electron beam and the x-ray FEL were studied during the 2009 commissioning period. The laser heater system is composed of a 4-dipole chicane; a 9-period, planar, permanent-magnet, adjustable-gap undulator at the center of the chicane; one OTR screen on each side of the undulator for electron/laser spatial alignment; and an IR laser (up to 15-MW power) which co-propagates with the electron beam inside the undulator generating a 758-nm energy modulation along the bunch. The final two dipoles of the 4-dipole chicane time-smear this modulation leaving only a thermal-like intrinsic energy spread within the bunch. Table 1 lists the main parameters for this system. The very bright electron beam required for an x-ray free-electron laser (FEL), such as the LCLS, is susceptible to a microbunching instability in the magnetic bunch compressors, prior to the FEL undulator. The uncorrelated electron energy spread in the LCLS can be increased by an order of magnitude to provide strong Landau damping against the instability without degrading the FEL performance. To this end, a 'laser-heater' system has been installed in the LCLS injector, which modulates the energy of a 135-MeV electron bunch with an IR laser beam in a short undulator, enclosed within a four-dipole chicane. The last half of the chicane time-smears the energy modulation leaving an effective thermal energy spread increase. We present the first commissioning results of this system, its operational issues, its impact on the microbunching instability, and finally its effect on the FEL performance.

  5. A Compact Disk Type Plasma Propulsion System with Modulated Magnetic Field for Nanoscale Space Vehicles

    SciTech Connect (OSTI)

    Fukuda, Takeshi; Ueda, Satoshi; Ohnishi, Yukihiro; Inomoto, Michiaki [Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, 565-0871 Osaka (Japan)

    2008-12-31T23:59:59.000Z

    A compact 5 mm disk type plasma thruster simply composed of only a set of antenna windings and bias field coil which produces significant thrust of 0.74 mN with rotating magnetic field has been proposed and successfully developed for future applications to low altitude nanosatellites. The key technology issue is that the rotating speed is set above the ion plasma frequency but far below the electron plasma frequency, in order to produce the electron drag current and axial electric field as a consequence of the interaction with the bias field. The formation of axial electric field was confirmed and the produced plasma density was >6x10{sup 18} m{sup -3}, whereas the power consumption is 500 W in the inductively coupled mode of operation. The anticipated thrust density and specific thrust could potentially be extended to 7.64 Nm{sup -2} and 850 s, respectively, which is comparable to conventional Hall effect thrusters.

  6. SU-E-T-136: Dosimetric Robustness of a Magnetic Resonance Imaging Guided Radiation Therapy (MR-IGRT) System

    SciTech Connect (OSTI)

    Rodriguez, V; Green, O; Wooten, H; Kashani, R; Mutic, S; Li, H [Washington University School of Medicine, St. Louis, MO (United States); Dempsey, J [View Ray Incorporated, Oakwood Village, OH (United States)

    2014-06-01T23:59:59.000Z

    Purpose: To test the radiation delivery robustness of the first MR-IGRT system using a commercial cylindrical diode array detector (ArcCHECK) and an ionization thimble chamber (Exradin A18). Methods: The MR-IGRT system is composed of three evenly spaced Co-60 sources on a rotating gantry located between two magnet halves. The collimator for each source consists of 30 doubly-focused leaf pairs that allow the system to deliver both conformal and intensity modulated (IMRT) treatment plans. The system's delivery robustness was tested over a span of 6 months from September 2013 through February 2014. This was achieved by repeatedly delivering 10 patient plans. These plans consisted of 2 conformal prostates, 2 IMRT prostates, 2 IMRT head and neck, 2 IMRT breast, 1 IMRT pancreas, and 1 IMRT bladder. The plans were generated with the system's treatment planning software. Once the plans were generated, quality assurance plans were created on a digital ArcCHECK dataset. The ArcCHECK used for testing was specially designed to be MR-compatible by moving the power supply outside of the magnetic field. The A18 ionization chamber was placed in a custom plastic plug insert in the center of the ArcCHECK. Gamma analysis was used with the ArcCHECK for relative dose evaluating both 3%/3mm and 2%/2mm. Absolute point dose was compared between ion chamber measurement and treatment plan. Results: The ArcCHECK passing rate remained constant over the 6 month period. The average passing rate for 3%/3mm and 2%/2mm analysis was 98.6% ± 0.7 and 88.8% ± 2.9, respectively. The ion chamber measurements showed little variation with an average percent difference between planned dose verses measured dose of 0.9% ± 0.7. Conclusion: Minimal differences were noted in the delivery of the 10 patient plans. Over a period that included acceptance testing, commissioning, and clinical deliveries, the MR-IGRT system remained consistent in radiation delivery.

  7. Passive magnetic bearing configurations

    DOE Patents [OSTI]

    Post, Richard F. (Walnut Creek, CA)

    2011-01-25T23:59:59.000Z

    A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.

  8. Magnetically attached sputter targets

    DOE Patents [OSTI]

    Makowiecki, D.M.; McKernan, M.A.

    1994-02-15T23:59:59.000Z

    An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

  9. Review and comparison of magnet designs for magnetic refrigeration

    E-Print Network [OSTI]

    Bjřrk, R; Smith, A; Pryds, N

    2014-01-01T23:59:59.000Z

    One of the key issues in magnetic refrigeration is generating the magnetic field that the magnetocaloric material must be subjected to. The magnet constitutes a major part of the expense of a complete magnetic refrigeration system and a large effort should therefore be invested in improving the magnet design. A detailed analysis of the efficiency of different published permanent magnet designs used in magnetic refrigeration applications is presented in this paper. Each design is analyzed based on the generated magnetic flux density, the volume of the region where this flux is generated and the amount of magnet material used. This is done by characterizing each design by a figure of merit magnet design efficiency parameter, $\\Lambda_\\mathrm{cool}$. The designs are then compared and the best design found. Finally recommendations for designing the ideal magnet design are presented based on the analysis of the reviewed designs.

  10. COMMON COIL MAGNET PROGRAM AT BNL.

    SciTech Connect (OSTI)

    GUPTA, R.; ANERELLA, M.; COZZOLINO, J.; ESCALLIER, J.; GANETIS, G.; GHOSH, A.; HARRISON, M.; MORGAN, G.; MURATORE, J.; PARKER, B.; SAMPSON, W.; WANDERER, P.

    2000-09-17T23:59:59.000Z

    The goal of the common coil magnet R&D program at Brookhaven National Laboratory (BNL) is to develop a 12.5 T, 40 mm aperture dipole magnet using ''React and Wind Technology'' with High Temperature Superconductors (HTS) playing a major role. Due to its ''conductor friendly'' nature, the common coil design is attractive for building high field 2-in-1 dipoles with brittle materials such as HTS and Nb{sub 3}Sn. At the current rate of development, it is expected that a sufficient amount of HTS with the required performance would be available in a few years for building a short magnet. In the interim, the first generation dipoles will be built with Nb{sub 3}Sn superconductor. They will use a ''React and Wind'' technology similar to that used in HTS and will produce a 12.5 T central field in a 40 mm aperture. The Nb{sub 3}Sn coils and support structure of this magnet will become a part of the next generation hybrid magnet with inner coils made of HTS. To develop various aspects of the technology in a scientific and experimental manner, a 10-turn coil program has been started in parallel. The program allows a number of concepts to be evaluated with a rapid throughput in a cost-effective way. Three 10-turn Nb{sub 3}Sn coils have been built and one HTS coil is under construction. The initial test results of this ''React & Wind'' 10-turn coil program are presented. It is also shown that a common coil magnet design can produce a field quality that is as good as a conventional cosine theta design.

  11. A Novel Integrated Magnetic Structure Based DC/DC Converter for Hybrid Battery/Ultracapacitor Energy Storage Systems

    SciTech Connect (OSTI)

    Onar, Omer C [ORNL

    2012-01-01T23:59:59.000Z

    This manuscript focuses on a novel actively controlled hybrid magnetic battery/ultracapacitor based energy storage system (ESS) for vehicular propulsion systems. A stand-alone battery system might not be sufficient to satisfy peak power demand and transient load variations in hybrid and plug-in hybrid electric vehicles (HEV, PHEV). Active battery/ultracapacitor hybrid ESS provides a better solution in terms of efficient power management and control flexibility. Moreover, the voltage of the battery pack can be selected to be different than that of the ultracapacitor, which will result in flexibility of design as well as cost and size reduction of the battery pack. In addition, the ultracapacitor bank can supply or recapture a large burst of power and it can be used with high C-rates. Hence, the battery is not subjected to supply peak and sharp power variations, and the stress on the battery will be reduced and the battery lifetime would be increased. Utilizing ultracapacitor results in effective capturing of the braking energy, especially in sudden braking conditions.

  12. Multiple temperature-induced magnetization reversals in SmCr{sub 1?x}Fe{sub x}O{sub 3} system

    SciTech Connect (OSTI)

    Yin, L.H.; Liu, Y.; Tan, S.G.; Zhao, B.C.; Dai, J.M. [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Song, W.H., E-mail: whsong@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); Sun, Y.P., E-mail: ypsun@issp.ac.cn [Key Laboratory of Materials Physics, Institute of Solid State Physics, Hefei 230031 (China); High Magnetic Field Laboratory, Chinese Academy of Sciences, Hefei 230031 (China)

    2013-10-15T23:59:59.000Z

    Graphical abstract: - Highlights: • Multiple temperature-induced magnetization reversals were observed in x = 0.1. • Coexistence of normal and inverse magnetocaloric effects was observed. • A reasonable model was proposed to explain the magnetization reversals. - Abstract: The structural and magnetic properties of the SmCr{sub 1?x}Fe{sub x}O{sub 3} (0 ? x ? 0.5) system have been investigated. Multiple temperature-induced magnetization reversals were observed in x = 0.1. The high-temperature magnetization reversal is due to the special spin structure, in which the net canted moment of the Cr-rich regions and the net moment of the Fe–Cr ordered regions orient in opposite direction; while the low temperature one can be ascribed to the spin reorientation. The sample with x = 0.5 exhibits the highest compensation temperature. Coexistence of normal and inverse magnetocaloric effects was observed in all doped samples. Potential applications in magnetic refrigeration based constant temperature bath near room temperature (?286 K) have been demonstrated.

  13. Thermal modeling of head disk interface system in heat assisted magnetic recording

    SciTech Connect (OSTI)

    Vemuri, Sesha Hari; Seung Chung, Pil; Jhon, Myung S., E-mail: mj3a@andrew.cmu.edu [Department of Chemical Engineering and Data Storage Systems Center, Carnegie Mellon University, 5000 Forbes Ave., Pittsburgh, Pennsylvania 15213 (United States); Min Kim, Hyung [Department of Mechanical System Engineering, Kyonggi University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

    2014-05-07T23:59:59.000Z

    A thorough understanding of the temperature profiles introduced by the heat assisted magnetic recording is required to maintain the hotspot at the desired location on the disk with minimal heat damage to other components. Here, we implement a transient mesoscale modeling methodology termed lattice Boltzmann method (LBM) for phonons (which are primary carriers of energy) in the thermal modeling of the head disk interface (HDI) components, namely, carbon overcoat (COC). The LBM can provide more accurate results compared to conventional Fourier methodology by capturing the nanoscale phenomena due to ballistic heat transfer. We examine the in-plane and out-of-plane heat transfer in the COC via analyzing the temperature profiles with a continuously focused and pulsed laser beam on a moving disk. Larger in-plane hotspot widening is observed in continuously focused laser beam compared to a pulsed laser. A pulsed laser surface develops steeper temperature gradients compared to continuous hotspot. Furthermore, out-of-plane heat transfer from the COC to the media is enhanced with a continuous laser beam then a pulsed laser, while the temperature takes around 140 fs to reach the bottom surface of the COC. Our study can lead to a realistic thermal model describing novel HDI material design criteria for the next generation of hard disk drives with ultra high recording densities.

  14. Synthetic creation of a chemotactic system via utilization of magnetically actuated microrobotic walkers

    E-Print Network [OSTI]

    Steimel, Joshua Paul

    2012-01-01T23:59:59.000Z

    Chemotaxis is a fundamental biological process that plays an important role in disease, reproduction, and most biological functions. Here, we present a radically novel method to create the first synthetic chemotactic system ...

  15. Safety of high speed guided ground transportation systems: Comparison of magnetic and electric fields of conventional and advanced electrified transportation systems. Final report, September 1992-March 1993

    SciTech Connect (OSTI)

    Dietrich, F.M.; Feero, W.E.; Jacobs, W.L.

    1993-08-01T23:59:59.000Z

    Concerns exist regarding the potential safety, environmental and health effects on the public and on transportation workers due to electrification along new or existing rail corridors, and to proposed maglev and high speed rail operations. Therefore, the characterization of electric and magnetic fields (EMF) produced by both steady (dc) and alternating currents (ac) at power frequency (50 Hz in Europe and 60 Hz in the U.S.) and above, in the Extreme Low Frequency (ELF) range (3-3000 Hz) is of interest. The report summarizes and compares the results of a survey of EMF characteristics (spatial, temporal and frequency bands) for representative conventional railroad and transit and advanced high-speed systems including: the German TR-07 maglev system; the Amtrak Northeast Corridor (NEC) and North Jersey Transit (NJT) trains; the Washington, DC Metrorail (WMATA) and the Boston, MA (MBTA) transit systems; and the French TGV-A high speed rail system. This comprehensive comparative EMF survey produced both detailed data and statistical summaries of EMF profiles, and their variability in time and space. EMF ELF levels for WMATA are also compared to those produced by common environmental sources at home, work, and under power lines, but have specific frequency signatures.

  16. Beta Beams for neutrino production: Heat deposition from decaying ions in superconducting magnets

    E-Print Network [OSTI]

    Wildner, Elena; Cerutti, Francesco

    This note describes studies of energy deposition in superconducting magnets from secondary ions in the “beta beam” decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code “ACCSIM” to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code “FLUKA” with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipol...

  17. Beta Beams for Neutrino Production Heat Deposition from Decaying Ions in Superconducting Magnets

    E-Print Network [OSTI]

    Wildner, Elena; Cerutti, F

    2008-01-01T23:59:59.000Z

    This report describes studies of energy deposition in superconducting magnets from secondary ions in the "beta beam" decay ring as described in the base-line scenario of the EURISOL Beta Beam Design Study. The lattice structure proposed in the Design Study has absorber elements inserted between the superconducting magnets to protect the magnet coils. We describe an efficient and small model made to carry out the study. The specially developed options in the beam code "ACCSIM" to track largely off-momentum particles has permitted to extract the necessary information to interface the transport and interaction code "FLUKA" with the aim to calculate the heat deposition in the magnets and the absorbers. The two beta emitters 18Ne10+ and 6He2+ used for neutrino and anti-neutrino production and their daughter ions have been tracked. The absorber system proposed in the Design Study is efficient to intercept the ions decayed in the arc straight sections as foreseen, however, the continuous decay in the dipoles induce ...

  18. A microprocessor-based system controlling a nuclear demagnetization refrigerator is described. Magnetization, precooling, and demagnetization are software~controlled as are heat

    E-Print Network [OSTI]

    Packard, Richard E.

    A microprocessor-based system controlling a nuclear demagnetization refrigerator is described. Magnetization, precooling, and demagnetization are software~controlled as are heat and persistent current. A microprocessor controller for a nuclear demagnetization refrigerator J.P. Eisenstein, G.W. Swift and R.E. Packard

  19. A direct search for Dirac magnetic monopoles

    E-Print Network [OSTI]

    Mulhearn, Michael James

    2005-01-01T23:59:59.000Z

    Magnetic monopoles are highly ionizing and curve in the direction of the magnetic field. A new dedicated magnetic monopole trigger at CDF, which requires large light pulses in the scintillators of the time-of-flight system, ...

  20. FELIX: construction and testing of a facility to study electromagnetic effects for first wall, blanket, and shield systems

    SciTech Connect (OSTI)

    Praeg, W.F.; Turner, L.R.; Biggs, J.A.; Knott, M.J.; Lari, R.J.; McGhee, D.G.; Wehrle, R.B.

    1983-01-01T23:59:59.000Z

    An experimental test facility for the study of electromagnetic effects in the FWBS systems of fusion reactors has been constructed over the past 1-1/2 years at Argonne National Laboratory (ANL). In a test volume of 0.76 m/sup 3/ a vertical pulsed 0.5 T dipole field (B < 50 T/s) is perpendicular to a 1 T solenoid field. Power supplies of 2.75 MW and 5.5 MW and a solid state switch rated 13 kV, 13.1 kA (170 MW) control the pulsed magnetic fields. The total stored energy in the coils is 2.13 MJ. The coils are designed for a future upgrade to 4 T or the solenoid and 1 T for the dipole field (a total of 23.7 MJ). This paper describes the design and construction features of the facility. These include the power supplies, the solid state switches, winding and impregnation of large dipole saddle coils, control of the magnetic forces, computer control of FELIX and of experimental data acquisition and analysis, and an initial experimental test setup to analyze the eddy current distribution in a flat disk.

  1. The chiral magnetic nanomotors

    E-Print Network [OSTI]

    Morozov, Konstantin I

    2013-01-01T23:59:59.000Z

    Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic field is in the focus of the modern biomedical applications. This technology relies on strong interaction of dynamic and magnetic degrees of freedom of the system. Here we study in detail various experimentally observed regimes of the helical nanomotor orientation and propulsion depending on the actuation frequency, and establish the relation of these two properties with remanent magnetization and geometry of the helical nanomotors. The theoretical predictions for the transition between the regimes and nanomotor orientation and propulsion speed are in excellent agreement with available experimental data. The proposed theory offers a few simple guidelines towards the optimal design of the magnetic nanomotors. In particular, efficient nanomotors should be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and have the geometry of a normal helix with a helical angle of 35-45 degrees.

  2. Electron Electric Dipole Moment from CP Violation in the Charged Higgs Sector

    E-Print Network [OSTI]

    David Bowser-Chao; Darwin Chang; Wai-Yee Keung

    1997-12-02T23:59:59.000Z

    The leading contributions to the electron (or muon) electric dipole moment due to CP violation in the charged Higgs sector are at the two-loop level. A careful analysis of the model-independent contribution is provided. We also consider specific scenarios to demonstrate how charged Higgs sector CP violation can naturally give rise to large electric dipole moments. Numerical results show that the electron electric dipole moment in such models can lie at the experimentally accessible level.

  3. Measuring the quantum efficiency of single radiating dipoles using a scanning mirror

    E-Print Network [OSTI]

    B. C. Buchler; T. Kalkbrenner; C. Hettich; V. Sandoghdar

    2005-06-17T23:59:59.000Z

    Using scanning probe techniques, we show the controlled manipulation of the radiation from single dipoles. In one experiment we study the modification of the fluorescence lifetime of a single molecular dipole in front of a movable silver mirror. A second experiment demonstrates the changing plasmon spectrum of a gold nanoparticle in front of a dielectric mirror. Comparison of our data with theoretical models allows determination of the quantum efficiency of each radiating dipole.

  4. Superconductive Magnetic Energy Storage (SMES) System Studies for Electrical Utility at Wisconsin 

    E-Print Network [OSTI]

    Boom, R. W.; Eyssa, Y. M.; Abdelsalem, M. K.; Huang, X.

    1988-01-01T23:59:59.000Z

    of the axial structure is approximately E; and the cost of refrigeration is a constant plus an E^2/3 term. Costs scale approximately from E^0.58 (low E) to E^0.71 (100 - 3000 MWh) to E ^0.78 (3000 to 10,000 MWh). The cost of the ac-dc conversion system is about...

  5. Gravity and magnetic features and their relationship to the geothermal system in southwestern South Dakota

    SciTech Connect (OSTI)

    Hildenbrand, T.G.; Kucks, R.P.

    1981-01-01T23:59:59.000Z

    An attempt is made to determine the sources that are responsible for producing geothermal anomalies observed within the southern Black Hills region. Lithologic and structural boundaries residing in the upper crust and their relationship to the geothermal system are discussed. A regional gravity survey was supplemented by a regional aeromagnetic survey.

  6. Single-magnet rotary flowmeter for liquid metals

    E-Print Network [OSTI]

    Priede, J?nis; Gerbeth, Gunter

    2010-01-01T23:59:59.000Z

    We present the theory of single-magnet flowmeter for liquid metals and compare it with experimental results. The flowmeter consists of a freely rotating permanent magnet, which is magnetized perpendicularly to the axle it is mounted on. When such a magnet is placed close to a tube carrying liquid metal flow, it rotates so that the driving torque due to the eddy currents induced by the flow is balanced by the braking torque induced by the rotation itself. The equilibrium rotation rate depends directly on the flow rate but not on the electrical conductivity of the metal or the magnet strength. We obtain simple analytical solutions for the force and torque on slowly moving and rotating magnets due to eddy currents in a layer of infinite horizontal extent. The predicted equilibrium rotation rate for a dipole agrees well with the magnet rotation rate measured at a stainless steel duct with a liquid sodium flow.

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

    E-Print Network [OSTI]

    Dekens, W G

    2015-01-01T23:59:59.000Z

    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.

  8. Synchrotron radiation interferences between small dipoles at LEP

    SciTech Connect (OSTI)

    Bovet, C., Burns, A., Meot, F., Placidi, M., Rossa, E., de Vries, J. [European Organization for Nuclear Research, Geneva (Switzerland)

    1997-06-01T23:59:59.000Z

    Synchrotron Radiation interferences between small dipoles in the very low (visible) frequency range have been studied at the LEP diagnostic mini-wiggler. Their understanding allowed a substantial brightness gain by adequate layout modifications. The phenomenon is described analytically in terms of time coherence effects. This serves as a basis for further detailed numerical simulations of the experiment by means of stepwise ray-tracing, and allows precise interpretation of the spectral, polarization and intensity measurements collected at LEP. It also provides guidelines for SR diagnostic at injection energy in LHC.

  9. DC Resistivity Survey (Pole-Dipole Array) | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.pngRoofs andCrops Ltd Jump to: navigation, searchDCPole-Dipole

  10. DSI Dipole Shear Sonic Imager | Open Energy Information

    Open Energy Info (EERE)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page onYou are now leaving Energy.gov You are now leaving Energy.gov You are being directedAnnualProperty EditCalifornia:PowerCER.pngRoofs andCrops Ltd Jump1-EA Jump to: navigation,DSI Dipole

  11. Computational Modeling of an MRI Guided Drug Delivery System Based on Magnetic Nanoparticle Aggregations for the Navigation of Paramagnetic Nanocapsules

    E-Print Network [OSTI]

    N. K. Lampropoulos; E. G. Karvelas; I. E. Sarris

    2015-04-14T23:59:59.000Z

    A computational method for magnetically guided drug delivery is presented and the results are compared for the aggregation process of magnetic particles within a fluid environment. The model is developed for the simulation of the aggregation patterns of magnetic nanoparticles under the influence of MRI magnetic coils. A novel approach for the calculation of the drag coefficient of aggregates is presented. The comparison against experimental and numerical results from the literature is showed that the proposed method predicts well the aggregations in respect to their size and pattern dependance, on the concentration and the strength of the magnetic field, as well as their velocity when particles are driven through the fluid by magnetic gradients.

  12. Mechanical design and analysis of an eight-pole superconducting vector magnet for soft x-ray magnetic dichroism measurements

    SciTech Connect (OSTI)

    Arbelaez, D.; Black, A.; Prestemon, S.O.; Wang, S.; Chen, J.; Arenholz, E.

    2010-01-13T23:59:59.000Z

    An eight-pole superconducting magnet is being developed for soft x-ray magnetic dichroism (XMD) experiments at the Advanced Light Source, Lawrence Berkley National Laboratory (LBNL). Eight conical Nb{sub 3}Sn coils with Holmium poles are arranged in octahedral symmetry to form four dipole pairs that provide magnetic fields of up to 5 T in any direction relative to the incoming x-ray beam. The dimensions of the magnet yoke as well as pole taper, diameter, and length were optimized for maximum peak field in the magnet center using the software package TOSCA. The structural analysis of the magnet is performed using ANSYS with the coil properties derived using a numerical homogenization scheme. It is found that the use of orthotropic material properties for the coil has an important influence in the design of the magnet.

  13. Enhancement of the CP-odd effect in the nuclear electric dipole moment of $^6$Li

    E-Print Network [OSTI]

    Yamanaka, Nodoka

    2015-01-01T23:59:59.000Z

    We calculate for the first time the electric dipole moment (EDM) of the $^6$Li nucleus within the alpha + p + n three-body cluster model using the Gaussian expansion method, assuming the one meson exchange P, CP-odd nuclear forces. It is found that the EDM of the $^6$Li is 2 times more sensitive on the isovector pion exchange P, CP-odd nuclear force than the deuteron EDM, due to the CP-odd interaction between the nucleons and the alpha cluster. The $^9$Be EDM is also calculated in the same framework as an alpha + alpha + n three-body system. We also test the ab initio calculation of the EDM of the deuteron, $^3$H and $^3$He nuclei using the realistic Argonne $v18$ nuclear force. In the ab initio calculations, good agreements with previous studies are obtained. We finally discuss the prospects for the new physics beyond the standard model.

  14. Enhancement of the CP-odd effect in the nuclear electric dipole moment of $^6$Li

    E-Print Network [OSTI]

    Nodoka Yamanaka; Emiko Hiyama

    2015-03-15T23:59:59.000Z

    We calculate for the first time the electric dipole moment (EDM) of the $^6$Li nucleus within the alpha + p + n three-body cluster model using the Gaussian expansion method, assuming the one meson exchange P, CP-odd nuclear forces. It is found that the EDM of the $^6$Li is 2 times more sensitive on the isovector pion exchange P, CP-odd nuclear force than the deuteron EDM, due to the CP-odd interaction between the nucleons and the alpha cluster. The $^9$Be EDM is also calculated in the same framework as an alpha + alpha + n three-body system. We also test the ab initio calculation of the EDM of the deuteron, $^3$H and $^3$He nuclei using the realistic Argonne $v18$ nuclear force. In the ab initio calculations, good agreements with previous studies are obtained. We finally discuss the prospects for the new physics beyond the standard model.

  15. The permanent electric dipole moment of thorium sulfide, ThS

    SciTech Connect (OSTI)

    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)

    2014-01-14T23:59:59.000Z

    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.

  16. Cryogenic Test of a 750 MHz Superconducting RF Dipole Crabbing Cavity

    SciTech Connect (OSTI)

    Castilla, Alejandro [ODU; Delayen, Jean R. [ODU, JLAB; Park, HyeKyoung [JLAB

    2014-07-01T23:59:59.000Z

    A superconducting rf dipole cavity has been designed to address the challenges of a high repetition rate (750 MHz), high current for both electron/ion species (0.5/3 A per bunch), and large crossing angle (50 mrad) at the interaction points (IPs) crabbing system for the Medium Energy Electron-Ion Collider (MEIC) proposed by Jefferson Lab. The cavity prototype built at Niowave, Inc. has been tested at the Jefferson Lab facilities. In this work we present a detailed analysis of the prototype cavity performance at 4 K and 2 K, corroborating the absence of hard multipacting barriers that could limit the desired transverse fields, along with the surface resistance (Rs) temperature dependency.

  17. Disordered electronic and magnetic systems - transition metal (Mn) and rare earth (Gd) doped amorphous group IV semiconductors (C, Si, Ge)

    E-Print Network [OSTI]

    Zeng, Li

    2007-01-01T23:59:59.000Z

    magnetic semiconductors: the europium chalcogenides. Phys.Classic examples are europium chalcogenides [3], Gd 3?x ? xmagnetic semiconductor europium chalcogenides, where the

  18. Structural, thermal, magnetic, and electronic transport properties of the LaNi?(Ge1-xPx)? system

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

    Goetsch, R. J.; Anand, V. K.; Pandey, Abhishek; Johnston, D. C.

    2012-02-01T23:59:59.000Z

    Polycrystalline samples of LaNi?(Ge1-xPx)? (x=0,0.25,0.50,0.75,1) were synthesized and their properties investigated by x-ray diffraction (XRD) measurements at room temperature and by heat capacity Cp, magnetic susceptibility ?, and electrical resistivity ? measurements versus temperature T from 1.8 to 350 K. Rietveld refinements of powder XRD patterns confirm that these compounds crystallize in the body-centered-tetragonal ThCr?Si?-type structure (space group I4/mmm) with composition-dependent lattice parameters that slightly deviate from Vegard's law. The ?(T) measurements showed a positive temperature coefficient for all samples from 1.8 to 300 K, indicating that all compositions in this system are metallic. The low-T Cp measurements yield amore »rather large Sommerfeld electronic specific heat coefficient ?=12.4(2) mJ/mol K˛ for x=0, reflecting a large density of states at the Fermi energy that is comparable with the largest values found for the AFe?As? class of materials with the same crystal structure. The ? decreases approximately linearly with x to 7.4(1) mJ/mol K˛ for x=1. The ? measurements show nearly temperature-independent paramagnetic behavior across the entire range of compositions except for LaNi?Ge?, where a broad peak is observed at ?300 K from ?(T) measurements up to 1000 K that may arise from short-range antiferromagnetic correlations in a quasi-two-dimensional magnetic system. High-accuracy Padé approximants representing the Debye lattice heat capacity and Bloch-Grüneisen electron-phonon resistivity functions versus T are presented and are used to analyze our experimental Cp(T) and ?(T) data, respectively, for 1.8K?T?300 K. The T dependences of ? for all samples are well-described over this T range by the Bloch-Grüneisen model, although the observed ?(300 K) values are larger than calculated from this model. A significant T dependence of the Debye temperature determined from the Cp(T) data was observed for each composition. No clear evidence for bulk superconductivity or any other long-range phase transition was found for any of the LaNi?(Ge1-xPx)? compositions studied.« less

  19. Structural, thermal, magnetic, and electronic transport properties of the LaNi?(Ge1-xPx)? system

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

    Goetsch, R. J.; Anand, V. K.; Pandey, Abhishek; Johnston, D. C.

    2012-02-01T23:59:59.000Z

    Polycrystalline samples of LaNi?(Ge1-xPx)? (x=0,0.25,0.50,0.75,1) were synthesized and their properties investigated by x-ray diffraction (XRD) measurements at room temperature and by heat capacity Cp, magnetic susceptibility ?, and electrical resistivity ? measurements versus temperature T from 1.8 to 350 K. Rietveld refinements of powder XRD patterns confirm that these compounds crystallize in the body-centered-tetragonal ThCr?Si?-type structure (space group I4/mmm) with composition-dependent lattice parameters that slightly deviate from Vegard's law. The ?(T) measurements showed a positive temperature coefficient for all samples from 1.8 to 300 K, indicating that all compositions in this system are metallic. The low-T Cp measurements yield a rather large Sommerfeld electronic specific heat coefficient ?=12.4(2) mJ/mol K˛ for x=0, reflecting a large density of states at the Fermi energy that is comparable with the largest values found for the AFe?As? class of materials with the same crystal structure. The ? decreases approximately linearly with x to 7.4(1) mJ/mol K˛ for x=1. The ? measurements show nearly temperature-independent paramagnetic behavior across the entire range of compositions except for LaNi?Ge?, where a broad peak is observed at ?300 K from ?(T) measurements up to 1000 K that may arise from short-range antiferromagnetic correlations in a quasi-two-dimensional magnetic system. High-accuracy Padé approximants representing the Debye lattice heat capacity and Bloch-Grüneisen electron-phonon resistivity functions versus T are presented and are used to analyze our experimental Cp(T) and ?(T) data, respectively, for 1.8K?T?300 K. The T dependences of ? for all samples are well-described over this T range by the Bloch-Grüneisen model, although the observed ?(300 K) values are larger than calculated from this model. A significant T dependence of the Debye temperature determined from the Cp(T) data was observed for each composition. No clear evidence for bulk superconductivity or any other long-range phase transition was found for any of the LaNi?(Ge1-xPx)? compositions studied.

  20. Exotic Magnetic Order in the Orbital-Selective Mott Regime of Multiorbital Systems

    SciTech Connect (OSTI)

    Rincon, Julian [Oak Ridge National Laboratory (ORNL)] [Oak Ridge National Laboratory (ORNL); Moreo, Adriana [ORNL] [ORNL; Alvarez, Gonzalo [ORNL] [ORNL; Dagotto, Elbio R [ORNL] [ORNL

    2014-01-01T23:59:59.000Z

    The orbital-selective Mott phase of multiorbital Hubbard models has been extensively analyzed before using static and dynamical mean-field approximations. In parallel, the properties of block states (antiferromagnetically coupled ferromagnetic spin clusters) in Fe-based superconductors have also been much discussed. The present effort uses numerically exact techniques in one-dimensional systems to report the observation of block states within the orbital-selective Mott phase regime, connecting two seemingly independent areas of research, and providing analogies with the physics of double-exchange models.