A Pionic Hadron Explains the Muon Magnetic Moment Anomaly
Rainer W. Schiel; John P. Ralston
2007-10-01
A significant discrepancy exists between experiment and calculations of the muon's magnetic moment. We find that standard formulas for the hadronic vacuum polarization term have overlooked pionic states known to exist. Coulomb binding alone guarantees $\\pi^+ \\pi^-$ states that quantum mechanically mix with the $\\rho$ meson. A simple 2-state mixing model explains the magnetic moment discrepancy for a mixing angle of order $\\alpha \\sim 10^{-2}$. The relevant physical state is predicted to give a tiny observable bump in the ratio R(s) of $e^+ e^-$ annihilation at a low energy not previously searched. The burden of proof is reversed for claims that conventional physics cannot explain the muon's anomalous moment.
Magnetic Dipole Moment of Neutrino
Samina S. Masood
2015-06-03
We recalculate the magnetic moment of neutrinos in a hot and dense medium. The magnetic dipole moment of neutrinos is modified at high temperature and chemical potential. We show that the magnetic dipole moment of electron neutrino does not get a significant contribution from thermal background to meet the cosmological bound. However, chemical potential contribution to the magnetic moment is non-ignorable even when chemical potential is an order of magnitude greater than the electron mass. It is demonstrated that this effect is more significant in the models with an extended Higgs sector through neutrino mixing.
The Muon Anomalous Magnetic Moment
Marc Knecht
2014-12-03
The calculations entering the prediction of the standard model value for the anomalous magnetic moment of the muon $a_\\mu$ are reviewed, and compared to the very accurate experimental measurement. The situation for the electron is discussed in parallel.
Hyperon polarization and magnetic moments
Lach, J.
1993-12-01
Inclusively produced hyperons with significant polarization were first observed at Fermilab about seventeen years ago. This and subsequent experiments showed that {Lambda}{degree} were produced polarized while {bar {Lambda}}{degree} had no polarization in the same kinematical region. This set the stage for many experiments which showed that most hyperons are produced polarized. Recent Fermilab experiments have showed that this phenomena is even more complex and theoretical understanding is still lacking. Nevertheless polarized hyperon beams have been an extremely useful experimental tool in measuring hyperon magnetic moments. Recently, magnetic moment precession of channeled particles in bent crystals has been observed. This opens the possibility of measuring the magnetic moments of charmed baryons.
Bonanos, Peter (East Brunswick, NJ)
1983-01-01
A toroidal magnet for confining a high magnetic field for use in fusion reactor research and nuclear particle detection. The magnet includes a series of conductor elements arranged about and fixed at its small major radius portion to the outer surface of a central cylindrical support each conductor element having a geometry such as to maintain the conductor elements in pure tension when a high current flows therein, and a support assembly which redistributes all or part of the tension which would otherwise arise in the small major radius portion of each coil element to the large major radius portion thereof.
Electric Dipole Moment of Magnetic Monopole
Makoto Kobayashi
2007-03-07
The electric dipole moment of magnetic monopoles with spin is studied in the N=2 supersymmetric gauge theory. The dipole moments of the electric charge distributions, as well as the dipole moments due to the magnetic currents, are calculated. The contribution of charge distribution of the fermion to the gyroelectric ratio is expressed by using zeta(3).
Detecting Neutrino Magnetic Moments with Conducting Loops
Apyan, Aram; Schmitt, Michael
2007-01-01
It is well established that neutrinos have mass, yet it is very difficult to measure those masses directly. Within the standard model of particle physics, neutrinos will have an intrinsic magnetic moment proportional to their mass. We examine the possibility of detecting the magnetic moment using a conducting loop. According to Faraday's Law of Induction, a magnetic dipole passing through a conducting loop induces an electromotive force, or EMF, in the loop. We compute this EMF for neutrinos in several cases, based on a fully covariant formulation of the problem. We discuss prospects for a real experiment, as well as the possibility to test the relativistic formulation of intrinsic magnetic moments.
Detecting Neutrino Magnetic Moments with Conducting Loops
Aram Apyan; Armen Apyan; Michael Schmitt
2007-09-23
It is well established that neutrinos have mass, yet it is very difficult to measure those masses directly. Within the standard model of particle physics, neutrinos will have an intrinsic magnetic moment proportional to their mass. We examine the possibility of detecting the magnetic moment using a conducting loop. According to Faraday's Law of Induction, a magnetic dipole passing through a conducting loop induces an electromotive force, or EMF, in the loop. We compute this EMF for neutrinos in several cases, based on a fully covariant formulation of the problem. We discuss prospects for a real experiment, as well as the possibility to test the relativistic formulation of intrinsic magnetic moments.
Theory of the Anomalous Magnetic Moment of the Electron
E. L. Koschmieder
2013-01-18
It is shown that it follows from our model of the electron that its magnetic moment has an anomalous part if the magnetic field energy is taken into account. That means that the magnetic moment of our model of the electron is 1.0000565 times larger than the measured magnetic moment of the electron.
Molecular CP-violating magnetic moment Andrei Derevianko1
Titov, Anatoly
Molecular CP-violating magnetic moment Andrei Derevianko1 and M. G. Kozlov2 1 Department of Physics Received 26 April 2005; published 6 October 2005 A concept of CP-violating T,P-odd permanent molecular magnetic moments CP is introduced. We relate the moments to the electric dipole moment of electron e
Inversion of marine magnetic anomalies by deconvolution
Harry, Dennis Lee
1983-01-01
magnetization, j(x), with a transfer function, g(x), which is dependant upon the location and orientation of the anomaly profile and the ridge axis relative to the earth's present magnetic field [Bott, 1967]. This is expressed as f(x) f g(x-C) ](C) d0... and Cox, 1972]. The inversion procedure used is to; 1) Numerically transform f(x) into the wavenumber domain, 2) Divide F(k) by the analytical expression for G(k) to obtain J(k), 3) Numerically inverse transform J(k) to obtain J(x). The normalized...
Porsev, S G; Flambaum, V V
2010-01-01
We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.
S. G. Porsev; J. S. M. Ginges; V. V. Flambaum
2011-03-02
We have considered a mechanism for inducing a time-reversal violating electric dipole moment (EDM) in atoms through the interaction of a nuclear EDM (d_N) with the hyperfine interaction, the "magnetic moment effect". We have derived the operator for this interaction and presented analytical formulas for the matrix elements between atomic states. Induced EDMs in the diamagnetic atoms 129Xe, 171Yb, 199Hg, 211Rn, and 225Ra have been calculated numerically. From the experimental limits on the atomic EDMs of 129Xe and 199Hg, we have placed the following constraints on the nuclear EDMs, |d_N(129Xe)|< 1.1 * 10^{-21} |e|cm and |d_N(199Hg)|< 2.8 * 10^{-24} |e|cm.
Automatic detection of UXO magnetic anomalies using extended Euler deconvolution
Automatic detection of UXO magnetic anomalies using extended Euler deconvolution Kristofer Davis1 , Yaoguo Li1 , and Misac Nabighian1 ABSTRACT We have developed an algorithm for the automatic detec- tion of compact and iso- lated anomalies; it has enabled us to perform automatic anomaly selection for further
Magnetic moments of light nuclei from lattice quantum chromodynamics
Beane, S.? R.; Chang, E.; Cohen, S.; Detmold, W.; Lin, H.? W.; Orginos, K.; Parreño, A.; Savage, M.? J.; Tiburzi, B.? C.
2014-12-16
We present the results of lattice QCD calculations of the magnetic moments of the lightest nuclei, the deuteron, the triton and ^{3}He, along with those of the neutron and proton. These calculations, performed at quark masses corresponding to m_{?} ~ 800 MeV, reveal that the structure of these nuclei at unphysically heavy quark masses closely resembles that at the physical quark masses. We find that the magnetic moment of ^{3}He differs only slightly from that of a free neutron, as is the case in nature, indicating that the shell-model configuration of two spin-paired protons and a valence neutron captures its dominant structure. Similarly a shell-model-like moment is found for the triton, ?_{3H} ~ ?_{p}. The deuteron magnetic moment is found to be equal to the nucleon isoscalar moment within the uncertainties of the calculations.
Magnetic moments of light nuclei from lattice quantum chromodynamics
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Beane, S.? R.; Chang, E.; Cohen, S.; Detmold, W.; Lin, H.? W.; Orginos, K.; Parreño, A.; Savage, M.? J.; Tiburzi, B.? C.
2014-12-16
We present the results of lattice QCD calculations of the magnetic moments of the lightest nuclei, the deuteron, the triton and 3He, along with those of the neutron and proton. These calculations, performed at quark masses corresponding to m? ~ 800 MeV, reveal that the structure of these nuclei at unphysically heavy quark masses closely resembles that at the physical quark masses. We find that the magnetic moment of 3He differs only slightly from that of a free neutron, as is the case in nature, indicating that the shell-model configuration of two spin-paired protons and a valence neutron captures itsmore »dominant structure. Similarly a shell-model-like moment is found for the triton, ?3H ~ ?p. The deuteron magnetic moment is found to be equal to the nucleon isoscalar moment within the uncertainties of the calculations.« less
Magnetic Moment Enhancement for Mn7 Cluster on Graphene
Liu, Xiaojie [Ames Laboratory; Wang, Cai-Zhuang [Ames Laboratory; Lin, Hai-Qing [Beijing Computational Science Research Center; Ho, Kai-Ming [Ames Laboratory
2014-08-21
Mn7 cluster on graphene with different structural motifs and magnetic orders are investigated systematically by first-principles calculations. The calculations show that Mn7 on graphene prefers a two-layer motif and exhibits a ferrimagnetic coupling. The magnetic moment of the Mn7 cluster increases from 5.0 ?B at its free-standing state to about 6.0 ?B upon adsorption on graphene. Mn7 cluster also induces about 0.3 ?B of magnetic moment in the graphene layer, leading to an overall enhancement of 1.3 ?B magnetic moment for Mn7 on graphene. Detail electron transfer and bonding analysis have been carried out to investigate the origin of the magnetic enhancement.
A New Measurement of the Muon Magnetic Anomaly
K. Jungmann; :; g-2 collaboration
2000-02-08
The muon magnetic anomaly may contain contributions from physics beyond the standard model. At the Brookhaven National Laboratory (BNL) a precision experiment aims for a measurement of the muon magnetic anomaly $a_{\\mu}$ to 0.35 ppm, where conclusions about various theoretical approaches beyond standard theory can be expected. The difference between the spin precession and cyclotron frequencies is measured in a magnetic storage ring with highly homogeneous field. Data taking is in progress and part of all recorded data has been analyzed. Combining all experimental results to date yields preliminarily $a_{\\mu}(expt)=1~165~921(5) \\cdot 10^{-9}$ (4 ppm) in agreement with standard theory.
Constraining the neutrino magnetic dipole moment from white dwarf pulsations
Córsico, Alejandro H; Bertolami, Marcelo M Miller; Kepler, S O; García-Berro, Enrique
2014-01-01
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...
Muon anomalous magnetic moment in a $SU(4) \\otimes U(1)_N$ model without exotic electric charges
D. Cogollo
2014-11-11
We study an electroweak gauge extension of the standard model, so called 3-4-1 model, which does not contain exotic electric charges and it is anomaly free. We discuss phenomenological constraints of the model and compute all the corrections to the muon magnetic moment. Mainly, we discuss different mass regimes and their impact on this correction, deriving for the first time direct limits on the masses of the neutral fermions and charged vector bosons. Interestingly, the model could address the reported muon anomalous magnetic moment excess, however it would demands a rather low scale of symmetry breaking, far below the current electroweak constraints on the model. Thus, if this excess is confirmed in the foreseeable future by the g-2 experiment at FERMILAB, this 3-4-1 model can be decisively ruled out since the model cannot reproduce a sizeable and positive contribution to the muon anomalous magnetic moment consistent with current electroweak limits.
Leptophilic dark matter and the anomalous magnetic moment of the muon
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Agrawal, Prateek; Chacko, Zackaria; Verhaaren, Christopher B.
2014-08-26
We consider renormalizable theories such that the scattering of dark matter off leptons arises at tree level, but scattering off nuclei only arises at loop. In this framework, the various dark matter candidates can be classified by their spins and by the forms of their interactions with leptons. In this study, we determine the corrections to the anomalous magnetic moment of the muon that arise from its interactions with dark matter. We then consider the implications of these results for a set of simplified models of leptophilic dark matter. When a dark matter candidate reduces the existing tension between themore »standard model prediction of the anomalous magnetic moment and the experimental measurement, the region of parameter space favored to completely remove the discrepancy is highlighted. Conversely, when agreement is worsened, we place limits on the parameters of the corresponding simplified model. These bounds and favored regions are compared against the experimental constraints on the simplified model from direct detection and from collider searches. Although these constraints are severe, we find there do exist limited regions of parameter space in these simple theories that can explain the observed anomaly in the muon magnetic moment while remaining consistent with all experimental bounds.« less
Constraining the neutrino magnetic dipole moment from white dwarf pulsations
Córsico, A.H.; Althaus, L.G.; García-Berro, E. E-mail: althaus@fcaglp.unlp.edu.ar E-mail: kepler@if.ufrgs.br
2014-08-01
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 (?{sub ?}) using an estimate of the rate of period change of the pulsating DB white dwarf star PG 1351+489. We employ state-of-the-art evolutionary and pulsational codes which allow us to perform a detailed asteroseismological period fit based on fully DB white dwarf evolutionary sequences. Plasmon neutrino emission is the dominant cooling mechanism for this class of hot pulsating white dwarfs, and so it is the main contributor to the rate of change of period with time (Pidot) for the DBV class. Thus, the inclusion of an anomalous neutrino emission through a non-vanishing magnetic dipole moment in these sequences notably influences the evolutionary timescales, and also the expected pulsational properties of the DBV stars. By comparing the theoretical Pidot value with the rate of change of period with time of PG 1351+489, we assess the possible existence of additional cooling by neutrinos with magnetic dipole moment. Our models suggest the existence of some additional cooling in this pulsating DB white dwarf, consistent with a non-zero magnetic dipole moment with an upper limit of ?{sub ?} ?< 10{sup -11} ?{sub B}. This bound is somewhat less restrictive than, but still compatible with, other limits inferred from the white dwarf luminosity function or from the color-magnitude diagram of the Globular cluster M5. Further improvements of the measurement of the rate of period change of the dominant pulsation mode of PG 1351+489 will be necessary to confirm our bound.
Magnetism of j = 1/2 moments on the fcc lattice in double perovskite...
Office of Scientific and Technical Information (OSTI)
Magnetism of j 12 moments on the fcc lattice in double perovskite Mott insulators Citation Details In-Document Search Title: Magnetism of j 12 moments on the fcc lattice in...
Magnetic response enhancement via electrically induced magnetic moments
B. Jungnitsch; J. Evers
2008-04-22
The realization of negative refraction in atomic gases requires a strong magnetic response of the atoms. Current proposals for such systems achieve an enhancement of the magnetic response by a suitable laser field configuration, but still rely on high gas densities. Thus further progress is desirable, and this requires an understanding of the precise mechanism for the enhancement. Therefore, here we study the magnetic and electric response to a probe field interacting with three-level atoms in ladder configuration. In our first model, the three transitions are driven by a control field and the electric and magnetic component of the probe field, giving rise to a closed interaction loop. In a reference model, the coherent driving is replaced by an incoherent pump field. A time-dependent analysis of the closed-loop system enables us to identify the different contributions to the medium response. A comparison with the reference system then allows one to identify the physical mechanism that leads to the enhancement. It is found that the enhancement occurs at so-called multiphoton resonance by a scattering of the coupling field and the electric probe field mode into the magnetic probe field mode. Based on these results, conditions for the enhancement are discussed.
Anomalous magnetic moment of the muon in a dispersive approach
Vladyslav Pauk; Marc Vanderhaeghen
2014-09-03
We present a new general dispersive formalism for evaluating the hadronic light-by-light scattering contribution to the anomalous magnetic moment of the muon. In the suggested approach, this correction is related to the imaginary part of the muon's electromagnetic vertex function. The latter may be directly related to measurable hadronic processes by means of unitarity and analyticity. As a test we apply the introduced formalism to the case of meson pole exchanges and find agreement with the direct two-loop calculation.
Deep-tow study of magnetic anomalies in the Pacific Jurassic Quiet Zone
Tominaga, Masako
2006-10-30
The Jurassic Quiet Zone (JQZ) is a region of low amplitude, difficult-to-correlate magnetic anomalies located over Jurassic oceanic crust. We collected 1200 km of new deep-tow magnetic anomaly profiles over the Pacific JQZ that complement 2 deep...
Probing neutrino magnetic moments at Spallation Neutron Source facilities
T. S. Kosmas; O. G. Miranda; D. K. Papoulias; M. Tortola; J. W. F. Valle
2015-07-15
Majorana neutrino electromagnetic properties are studied through neutral current coherent neutrino-nucleus scattering. We focus on the potential of the recently planned COHERENT experiment at the Spallation Neutron Source to probe muon-neutrino magnetic moments. The resulting sensitivities are determined on the basis of a chi^2 analysis employing realistic nuclear structure calculations in the context of the quasi-particle random phase approximation. We find that they can improve existing limits by half an order of magnitude. In addition, we show that these facilities allow for Standard Model precision tests in the low energy regime, with a competitive determination of the weak mixing angle. Finally, they also offer the capability to probe other electromagnetic neutrino properties, such as the neutrino charge-radius. We illustrate our results for various choices of experimental setup and target material.
Shell structure of potassium isotopes deduced from their magnetic moments
J. Papuga; M. L. Bissell; K. Kreim; C. Barbieri; K. Blaum; M. De Rydt; T. Duguet; R. F. Garcia Ruiz; H. Heylen; M. Kowalska; R. Neugart; G. Neyens; W. Nortershauser; M. M. Rajabali; R. Sanchez; N. Smirnova; V. Soma; D. T. Yordanov
2014-10-03
\\item[Background] Ground-state spins and magnetic moments are sensitive to the nuclear wave function, thus they are powerful probes to study the nuclear structure of isotopes far from stability. \\item[Purpose] Extend our knowledge about the evolution of the $1/2^+$ and $3/2^+$ states for K isotopes beyond the $N = 28$ shell gap. \\item[Method] High-resolution collinear laser spectroscopy on bunched atomic beams. \\item[Results] From measured hyperfine structure spectra of K isotopes, nuclear spins and magnetic moments of the ground states were obtained for isotopes from $N = 19$ up to $N = 32$. In order to draw conclusions about the composition of the wave functions and the occupation of the levels, the experimental data were compared to shell-model calculations using SDPF-NR and SDPF-U effective interactions. In addition, a detailed discussion about the evolution of the gap between proton $1d_{3/2}$ and $2s_{1/2}$ in the shell model and {\\it{ab initio}} framework is also presented. \\item[Conclusions] The dominant component of the wave function for the odd-$A$ isotopes up to $^{45}$K is a $\\pi 1d_{3/2}^{-1}$ hole. For $^{47,49}$K, the main component originates from a $\\pi 2s_{1/2}^{-1}$ hole configuration and it inverts back to the $\\pi 1d_{3/2}^{-1}$ in $^{51}$K. For all even-$A$ isotopes, the dominant configuration arises from a $\\pi 1d_{3/2}^{-1}$ hole coupled to a neutron in the $\
Giant Magnetic Moments and Magnetic Bistability of Stoichiomatric MnO Clusters
Nayak, S.K.; Jena, P. [Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)] [Physics Department, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)
1998-10-01
{ital Abthinspthinspinitio} calculations based on density functional theory and generalized gradient approximation reveal many unusual features of stoichiometric (MnO){sub x} (x{le}9) clusters that contrast with their bulk behavior. The clusters are ferromagnetic and carry atomiclike magnetic moments ranging from 4{mu}{sub B} to 5{mu}{sub B} per MnO unit, and the moments are localized at the Mn sites. The (MnO){sub 8} cluster, in particular, exhibits nearly degenerate ferromagnetic and atypical antiferromagnetic solutions with the ferromagnetic structure carrying a moment of 40{mu}{sub B} . The structures of (MnO){sub x} clusters are also unique with cubic and hexagonal forms competing for stability. (MnO){sub 2} and (MnO){sub 3} are unusually stable and form the foundation for further growth. {copyright} {ital 1998} {ital The American Physical Society}
Overton, W.C. Jr.; Steyert, W.A. Jr.
1981-05-22
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.
K. Azizi
2009-02-16
Due to the very short life time of the $\\Delta$ baryons, a direct measurement on the electromagnetic moments of these systems is almost impossible in the experiment and can only be done indirectly. Although only for the magnetic dipole moments of $\\Delta^{++}$ and $\\Delta^{+}$ systems there are some experimental data, the theoretical, phenomenological and lattice calculations could play crucial role. In present work, the magnetic dipole ($\\mu_{\\Delta}$) , electric quadrupole ($Q_{\\Delta}$) and magnetic octupole ($O_{\\Delta}$) moments of these baryons are computed within the light cone QCD sum rules. The results are compared with the predictions of the other phenomenological approaches, lattice QCD and existing experimental data.
Solar neutrino oscillations and bounds on neutrino magnetic moment and solar magnetic field
E. Kh. Akhmedov; J. Pulido
2002-09-18
If the observed deficit of solar neutrinos is due to neutrino oscillations, neutrino conversions caused by the interaction of their transition magnetic moments with the solar magnetic field (spin-flavour precession) can still be present at a subdominant level. In that case, the combined action of neutrino oscillations and spin-flavour precession can lead to a small but observable flux of electron antineutrinos coming from the sun. Non-observation of these nuebar's could set limits on neutrino transition moment \\mu and the strength and coordinate dependence of the solar magnetic field B_\\perp. The sensitivity of the nuebar flux to the product \\mu B_\\perp is strongest in the case of the vacuum oscillation (VO) solution of the solar neutrino problem; in the case of the LOW solution, it is weaker, and it is the weakest for the LMA solution. For different solutions, different characteristics of the solar magnetic field B_\\perp(r) are probed: for the VO solution, the nuebar flux is determined by the integral of B_\\perp(r) over the solar convective zone, for LMA it is determined by the magnitude of B_\\perp in the neutrino production region, and for LOW it depends on the competition between this magnitude and the derivative of B_\\perp(r) at the surface of the sun.
New bounds on neutrino electric millicharge from GEMMA experiment on neutrino magnetic moment
Victor B. Brudanin; Dmitry V. Medvedev; Alexander S. Starostin; Alexander I. Studenikin
2014-11-09
Using the new limit on the neutrino anomalous magnetic moment recently obtained by GEMMA experiment we get an order-of-magnitude estimation for possible new direct upper bound on the neutrino electric millicharge $\\mid q_{\
Energy Dependence of Solar Neutrino Suppression and Bounds on the Neutrino Magnetic Moment
Joao Pulido; Ana M. Mourao
1998-03-02
An analysis of neutrino electron scattering as applied to the SuperKamiokande solar neutrino experiment with the data from the Homestake experiment leads to an upper bound on the neutrino magnetic moment in the range $\\mu_{\
Trapped Positrons for High-Precision Magnetic Moment Measurements
Gabrielse, Gerald
Hoogerheide to The Department of Physics in partial fulfillment of the requirements for the degree of Doctor moments, a greatly improved test of lepton CPT symmetry, and an improved de- termination of the fine
Magnetic moment for the negative parity $?\\to ?^0$ transition in light cone QCD sum rules
T. M. Aliev; M. Savc?
2015-09-21
The magnetic moment of the $\\Lambda \\to \\Sigma^0$ transition between negative parity, baryons is calculated in framework of the QCD sum rules approach, using the general form of the interpolating currents. The pollution arising from the positive--to--positive, and positive to negative parity baryons are eliminated by constructing the sum rules for different Lorentz structures. Nonzero value of the considered magnetic moment can be attributed to the violation of the $SU(3)$ symmetry.
Characterization and removal of errors due to local magnetic anomalies in directional drilling of Geophysics, Colorado School of Mines Summary Directional drilling has evolved over the last few decades utilizes a technique known as magnetic Measurement While Drilling (MWD). Vector measurements of geomagnetic
Magnetic-Compton-scattering study of spin moments in UFe{sub 2}
Lawson, P.K.; Cooper, M.J.; Dixon, M.A.; Timms, D.N.; Zukowski, E.; Itoh, F.; Sakurai, H.
1997-08-01
Spin moments were derived from the magnetic-Compton profile of UFe{sub 2}, which was measured using 59.38-keV circularly polarized synchrotron radiation from the Accumulation Ring Source at KEK, Japan. Although the net moment on the uranium site is no more than a tenth of a Bohr magneton, the individual spin and orbital moments, which are coupled antiparallel, are much larger and it is the spin moment that can be determined in magnetic-Compton scattering. The data have been analyzed in terms of the U 5f, Fe 3d and delocalized spin moments. The observed uranium-5f spin moment is less than half (i.e., {lt}0.25{mu}{sub B}) and the diffuse spin moment more than double (i.e., {gt}0.20{mu}{sub B}) those predicted from theory. These values compare favorably with those deduced from neutron measurements of the total magnetization. {copyright} {ital 1997} {ital The American Physical Society}
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
Nouri, N; Brown, M A; Carr, R; Filippone, B; Osthelder, C; Plaster, B; Slutsky, S; Swank, C
2015-01-01
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
N. Nouri; A. Biswas; M. A. Brown; R. Carr; B. Filippone; C. Osthelder; B. Plaster; S. Slutsky; C. Swank
2015-11-10
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
A prototype vector magnetic field monitoring system for a neutron electric dipole moment experiment
N. Nouri; A. Biswas; M. A. Brown; R. Carr; B. Filippone; C. Osthelder; B. Plaster; S. Slutsky; C. Swank
2015-08-17
We present results from a first demonstration of a magnetic field monitoring system for a neutron electric dipole moment experiment. The system is designed to reconstruct the vector components of the magnetic field in the interior measurement region solely from exterior measurements.
Kapitza problem for the magnetic moments of synthetic antiferromagnetic systems
Dzhezherya, Yu. I.; Demishev, K. O.; Korenivskii, V. N.
2012-08-15
The dynamics of magnetization in synthetic antiferromagnetic systems with the magnetic dipole coupling in a rapidly oscillating field has been examined. It has been revealed that the system can behave similar to the Kapitza pendulum. It has been shown that an alternating magnetic field can be efficiently used to control the magnetic state of a cell of a synthetic antiferromagnet. Analytical relations have been obtained between the parameters of such an antiferromagnet and an external magnetic field at which certain quasistationary states are implemented.
First observation of magnetic moment precession of channeled particles in bent crystals
Chen, D.; Albuquerque, I.F.; Baublis, V.V.; Bondar, N.F.; Carrigan, R.A. Jr.; Cooper, P.S.; Lisheng, D.; Denisov, A.S.; Dobrovolsky, A.V.; Dubbs, T.; Endler, A.M.F.; Escobar, C.O.; Foucher, M.; Golovtsov, V.L.; Goritchev, P.A.; Gottschalk, H.; Gouffon, P.; Grachev, V.T.; Khanzadeev, A.V.; Kubantsev, M.A.; Kuropatkin, N.P.; Lach, J.; Lang Pengfei; Lebedenko, V.N.; Li Chengze; Li Yunshan; Mahon, J.R.P.; McCliment, E.; Morelos, A.; Newsom, C.; Pommot Maia, M.C.; Samsonov, V.M.; Schegelsky, V.A.; Shi Huanzhang; Smith, V.J.; Sun, C.R.; Tang Fukun; Terentyev, N.K.; Timm, S.; Tkatch, I.I.; Uvarov, L.N.; Vorobyov, A.A.; Yan Jie; Zhao Wenheng; Zheng Shuchen; Zhong Yuanyuan Institute of High Energy Physics, Beijing H. H. Wills Physics Laboratory, University of Bristol Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 Fermi National Accelerator Laboratory, Batavia, Illinois 60510
1992-12-07
Spin precession of channeled particles in bent crystals has been observed for the first time. Polarized [Sigma][sup +] were channeled using bent Si crystals. These crystals provided an effective magnetic field of 45 T which resulted in a measured spin precession of 60[plus minus]17[degree]. This agrees with the prediction of 62[plus minus]2[degree] using the world average of [Sigma][sup +] magnetic moment measurements. This new technique gives a [Sigma][sup +] magnetic moment of (2.40[plus minus]0.46[plus minus]0.40)[mu][sub [ital N
Magnetic Anomalies on Io and Their Relationship to the Spatial Distribution of Volcanic Centers
Knicely, Joshua
2015-04-23
and observation altitude ...................................................... 43 1 1. INTRODUCTION Io is the most volcanically active body in the solar system due to tidal heating. The intense heating is produced by a Laplace orbital resonance with Jupiter..., for example, indicates the past presence of a powerful magnetic field and an early stage of plate tectonics as deduced from observed magnetic stripes and apparent transform faults. The magnetic anomaly pattern on Mars contributes to the hypothesis that many...
Electric/magnetic duality for chiral gauge theories with anomaly cancellation
Jan De Rydt; Torsten T. Schmidt; Mario Trigiante; Antoine Van Proeyen; Marco Zagermann
2009-02-07
We show that 4D gauge theories with Green-Schwarz anomaly cancellation and possible generalized Chern-Simons terms admit a formulation that is manifestly covariant with respect to electric/magnetic duality transformations. This generalizes previous work on the symplectically covariant formulation of anomaly-free gauge theories as they typically occur in extended supergravity, and now also includes general theories with (pseudo-)anomalous gauge interactions as they may occur in global or local N=1 supersymmetry. This generalization is achieved by relaxing the linear constraint on the embedding tensor so as to allow for a symmetric 3-tensor related to electric and/or magnetic quantum anomalies in these theories. Apart from electric and magnetic gauge fields, the resulting Lagrangians also feature two-form fields and can accommodate various unusual duality frames as they often appear, e.g., in string compactifications with background fluxes.
The measurement of the magnetic moment of sigma plus using channeling in bent crystals
Chen, D.
1992-01-01
The measurement of baryon magnetic moments has played an important role in determining the inner structures of baryons and constraining the quark models. The magnetic moments of the spin one-half baryons have been measured with good accuracy. The measurement of the magnetic moment of charm and beauty baryons is a challenge to experimental physics because their life-times are a factor of 1000 shorter than conventional hyperons. A new technique for measuring the magnetic moment of short-lived positively charged particles by using channeling in bent crystals has been tested in Fermilab Proton Center by using a polarized hyperon beam, specifically a [Sigma][sup +] beam. Two 4.5 cm long silicon crystals were bent by 1.6 mrad. There are eight implanted detectors on the surface of each crystal. These detectors are designed to measure the energy loss of those particles which pass through the crystal, and therefore allow selection of channeling particles. The bent crystal can provide to a relativistic channeling particle a very strong effective magnetic field. Under such a field, the author observed spin precession of the channeled [Sigma][sup +] by an angle of the order of one radian. By measuring this precession angle, the value was found for the magnetic moment of the [Sigma][sup +], 2.40 [+-] 0.46 [+-] 0.40 [mu][sub N], the uncertainties being statistical and systematical, respectively. This value is consistent with the world average value of 2.42 [+-] 0.05 [mu][sub N]. This new technique may be applied to measure the magnetic moments of short-lived positively charged particle such as [Lambda][sup +][sub c] in the future.
Gravity and magnetic anomalies and the deep structure of the Parnaiba cratonic basin, Brazil
Watts, A. B. "Tony"
Gravity and magnetic anomalies and the deep structure of the Parnaiba cratonic basin, Brazil A. B profile across the Parnaiba cratonic basin in NorthEast Brazil. The purpose of this project is to acquire margin of Parnaíba Basin, Brazil. Geophysics 64: 337-356. Ussami N, Cogo de Sa N, Molina EC. 1993
Neutrinoless double beta decay mediated by the neutrino magnetic moment
Marek Gó?d?; Wies?aw A. Kami?ski
2014-11-07
We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\
Neutrinoless double beta decay mediated by the neutrino magnetic moment
Gó?d?, Marek
2014-01-01
We present a new channel of the neutrinoless double beta decay. In this scenario neutrinos not only oscillate inside the nucleus but also interact with an external non-uniform magnetic field. We assume that the field rotates about the direction of motion of the neutrino and show, that for a certain speed of rotation the half-life of the $0\
Yannis Burnier; Dmitri E. Kharzeev; Jinfeng Liao; Ho-Ung Yee
2011-03-07
Chiral Magnetic Wave (CMW) is a gapless collective excitation of quark-gluon plasma in the presence of external magnetic field that stems from the interplay of Chiral Magnetic (CME) and Chiral Separation Effects (CSE); it is composed by the waves of the electric and chiral charge densities coupled by the axial anomaly. We consider CMW at finite baryon density and find that it induces the electric quadrupole moment of the quark-gluon plasma produced in heavy ion collisions: the "poles" of the produced fireball (pointing outside of the reaction plane) acquire additional positive electric charge, and the "equator" acquires additional negative charge. We point out that this electric quadrupole deformation lifts the degeneracy between the elliptic flows of positive and negative pions leading to $v_2(\\pi^+) < v_2(\\pi^-)$, and estimate the magnitude of the effect.
Maurice Benayoun; Johan Bijnens; Tom Blum; Irinel Caprini; Gilberto Colangelo; Henryk Czy?; Achim Denig; Cesareo A. Dominguez; Simon Eidelman; Christian S. Fischer; Paolo Gauzzi; Yuping Guo; Andreas Hafner; Masashi Hayakawa; Gregorio Herdoiza; Martin Hoferichter; Guangshun Huang; Karl Jansen; Fred Jegerlehner; Benedikt Kloss; Bastian Kubis; Zhiqing Liu; William Marciano; Pere Masjuan; Harvey B. Meyer; Tsutomu Mibe; Andreas Nyffeler; Vladimir Pascalutsa; Vladyslav Pauk; Michael R. Pennington; Santiago Peris; Christoph F. Redmer; Pablo Sanchez-Puertas; Boris Shwartz; Evgeny Solodov; Dominik Stoeckinger; Thomas Teubner; Marc Unverzagt; Marc Vanderhaeghen; Magnus Wolke
2014-07-21
We present the mini-proceedings of the workshops Hadronic contributions to the muon anomalous magnetic moment: strategies for improvements of the accuracy of the theoretical prediction and $(g-2)_{\\mu}$: Quo vadis?, both held in Mainz from April 1$^{\\rm rst}$ to 5$^{\\rm th}$ and from April 7$^{\\rm th}$ to 10$^{\\rm th}$, 2014, respectively.
Quark Contributions to Baryon Magnetic Moments in Full, Quenched and Partially Quenched QCD
Derek B. Leinweber
2004-06-02
The chiral nonanalytic behaviour of quark-flavor contributions to the magnetic moments of octet baryons are determined in full, quenched and partially-quenched QCD, using an intuitive and efficient diagrammatic formulation of quenched and partially-quenched chiral perturbation theory. The technique provides a separation of quark-sector magnetic-moment contributions into direct sea-quark loop, valence-quark, indirect sea-quark loop and quenched valence contributions, the latter being the conventional view of the quenched approximation. Both meson and baryon mass violations of SU(3)-flavor symmetry are accounted for. Following a comprehensive examination of the individual quark-sector contributions to octet baryon magnetic moments, numerous opportunities to observe and test the underlying structure of baryons and the nature of chiral nonanalytic behavior in QCD and its quenched variants are discussed. In particular, the valence u-quark contribution to the proton magnetic moment provides the optimal opportunity to directly view nonanalytic behavior associated with the meson cloud of full QCD and the quenched meson cloud of quenched QCD. The u quark in Sigma^+ provides the best opportunity to display the artifacts of the quenched approximation.
Spins and magnetic moments of 58;60;62;64Mn ground states and isomers
H. Heylen; C. Babcock; J. Billowes; M. L. Bissell; K. Blaum; P. Campbell; B. Cheal; R. F. Garcia Ruiz; Ch. Geppert; W. Gins; M. Kowalska; K. Kreim; S. M. Lenzi; I. D. Moore; R. Neugart; G. Neyens; W. Nörtershäuser; J. Papuga; D. T. Yordanov
2015-08-25
The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58;60;62;64Mn are now firmly determined to be I = 1 along with an I = 4 assignment for the isomeric states in 58;60;62Mn. The I = 1 magnetic moments show a decreasing trend with increasing neutron number while the I = 4 moments remain quite constant between N = 33 and N = 37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellent agreement of the ground state moments with the predictions from the LNPS calculations illustrates the need for an increasing amount of proton excitations across Z = 28 and neutron excitations across N = 40 in the ground state wave functions from N = 37 onwards.
Spins and magnetic moments of 58;60;62;64Mn ground states and isomers
Heylen, H; Billowes, J; Bissell, M L; Blaum, K; Campbell, P; Cheal, B; Ruiz, R F Garcia; Geppert, Ch; Gins, W; Kowalska, M; Kreim, K; Lenzi, S M; Moore, I D; Neugart, R; Neyens, G; Nörtershäuser, W; Papuga, J; Yordanov, D T
2015-01-01
The odd-odd 54;56;58;60;62;64Mn isotopes (Z = 25) were studied using bunched-beam collinear laser spectroscopy at ISOLDE, CERN. From the measured hyperfine spectra the spins and magnetic moments of Mn isotopes up to N = 39 were extracted. The previous tentative ground state spin assignments of 58;60;62;64Mn are now firmly determined to be I = 1 along with an I = 4 assignment for the isomeric states in 58;60;62Mn. The I = 1 magnetic moments show a decreasing trend with increasing neutron number while the I = 4 moments remain quite constant between N = 33 and N = 37. The results are compared to large-scale shell-model calculations using the GXPF1A and LNPS effective interactions. The excellent agreement of the ground state moments with the predictions from the LNPS calculations illustrates the need for an increasing amount of proton excitations across Z = 28 and neutron excitations across N = 40 in the ground state wave functions from N = 37 onwards.
Magnetism of j = 1/2 moments on the fcc lattice in double perovskite Mott insulators
Aczel, Adam A [ORNL; Cook, Ashley [University of Toronto, Canada; Matern, Stephanie [University of Cologne, Germany; Hickey, Ciaran [University of Toronto, Canada; Paramekanti, Arun [University of Toronto, Canada
2015-01-01
Motivated by experiments on La2ZnIrO6 and La2MgIrO6, we study the magnetism of spin-orbit coupled jeff = 1/2 iridium moments on the three-dimensional geometrically-frustrated face-centered cubic lattice. The symmetry-allowed nearest-neighbor interaction includes Heisenberg, Kitaev, and symmetric off-diagonal exchange. Using Luttinger-Tisza and Monte Carlo simulations, we find a rich variety of orders, including collinear A-type antiferromagnetism, collinear stripe order with moments along the {111}-direction, and incommensurate non-coplanar spirals, and determine their magnetic ordering transition temperatures. We argue that thermodynamic data on these iridates underscore the presence of a dominant Kitaev exchange, and suggest a possible resolution to the puzzle of why La2ZnIrO6, but not La2MgIrO6, exhibits 'weak' ferromagnetism.
Time-odd triaxial relativistic mean field approach for nuclear magnetic moments
J. M. Yao; H. Chen; J. Meng
2006-06-21
The time-odd triaxial relativistic mean field approach is developed and applied to the investigation of the ground-state properties of light odd-mass nuclei near the double-closed shells. The nuclear magnetic moments including the isoscalar and isovector ones are calculated and good agreement with Schmidt values is obtained. Taking $^{17}$F as an example, the splitting of the single particle levels (around $~0.7$ MeV near the Fermi level), the nuclear current, the core polarizations, and the nuclear magnetic potential, i.e., the spatial part of the vector potential, due to the violation of the time reversal invariance are investigated in detail.
Regular and chaotic dynamics of a chain of magnetic dipoles with moments of inertia
Shutyi, A. M. [Ulyanovsk State University (Russian Federation)], E-mail: shuty@mail.ru
2009-05-15
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.
Evidence of half-metallic interface magnetism via local moment formation in Co based Heusler alloys
Telling, N. D.; Keatley, P.S.; van der Laan, G.; Hicken, R.J.; Arenholz, E.; Sakuraba, Y.; Oogane, M.; Ando, Y.; Miyazaki, T.
2008-08-18
In this work we use a combination of x-ray magnetic circular and linear dichroism (XMCD and XMLD) techniques to examine the formation of local moments in Heusler alloys of the composition Co{sub 2}MnX (where X=Si or Al). The existence of local moments in a half-metallic system is reliant upon the band gap in the minority-spin states. By utilizing the element-specific nature of x-ray techniques we are able to explore the origin of the minority-spin band gap in the partial density of states (PDOS), via the degree of localization of moments on Co and Mn atoms. We observe a crucial difference in the localization of the Co moment when comparing Co{sub 2}MnSi (CMS) and Co{sub 2}MnAl (CMA) films that is consistent with the predicted larger minority-spin gap in the Co PDOS for CMS. These results provide important evidence for the dominant role of the Co minority-spin states in realizing half-metallic ferromagnetism (HMF) in these Heusler alloys. They also demonstrate a direct method for measuring the degree of interfacial HMF in the raw materials without the need for fabricating spin-transport devices.
Aliev, T M
2015-01-01
The magnetic moment of the $\\Lambda \\to \\Sigma^0$ transition between negative parity, baryons is calculated in framework of the QCD sum rules approach, using the general form of the interpolating currents. The pollution arising from the positive--to--positive, and positive to negative parity baryons are eliminated by constructing the sum rules for different Lorentz structures. Nonzero value of the considered magnetic moment can be attributed to the violation of the $SU(3)$ symmetry.
Atomic moments in Mn2CoAl thin films analyzed by X-ray magnetic circular dichroism
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jamer, M. E.; Assaf, B. A.; Sterbinsky, G. E.; Arena, D. A.; Heiman, D.
2014-12-05
Spin gapless semiconductors are known to be strongly affected by structural disorder when grown epitaxially as thin films. The magnetic properties of Mn2CoAl thin films grown on GaAs (001) substrates are investigated here as a function of annealing. This study investigates the atomic-specific magnetic moments of Mn and Co atoms measured through X-ray magnetic circular dichroism as a function of annealing and the consequent structural ordering. Results indicate that the structural distortion mainly affects the Mn atoms as seen by the reduction of the magnetic moment from its predicted value.
Atomic moments in Mn2CoAl thin films analyzed by X-ray magnetic circular dichroism
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jamer, M. [Northwestern Univ., Evanston, IL (United States). Dept. of Physics; Sterbinsky, G. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Photon Sciences Directorate; Assaf, B. [Northwestern Univ., Evanston, IL (United States). Dept. of Physics; Arena, D. [Brookhaven National Laboratory (BNL), Upton, NY (United States). Photon Sciences Directorate; Heiman, D. [Northwestern Univ., Evanston, IL (United States). Dept. of Physics
2014-12-07
Spin gapless semiconductors are known to be strongly affected by structural disorder when grown epitaxially as thin films. The magnetic properties of Mn2CoAl thin films grown on GaAs (001) substrates are investigated here as a function of annealing. This study investigates the atomic-specific magnetic moments of Mn and Co atoms measured through X-ray magnetic circular dichroism as a function of annealing and the consequent structural ordering. The results indicate that the structural distortion mainly affects the Mn atoms as seen by the reduction of the magnetic moment from its predicted value. (auth)
Itinerancy enhanced quantum fluctuation of magnetic moments in iron-based superconductors
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Tam, Yu -T.; Ku, W.; Yao, D. -X.
2015-09-10
We investigate the influence of itinerant carriers on dynamics and fluctuation of local moments in Fe-based superconductors, via linear spin-wave analysis of a spin-fermion model containing both itinerant and local degrees of freedom. Surprisingly against the common lore, instead of enhancing the (?,0) order, itinerant carriers with well nested Fermi surfaces is found to induce significant amount of spatial and temporal quantum fluctuation that leads to the observed small ordered moment. Interestingly, the underlying mechanism is shown to be intra-pocket nesting-associated long-range coupling, rather than the previously believed ferromagnetic double-exchange effect. This challenges the validity of ferromagnetically compensated first-neighbor couplingmore »reported from short-range fitting to the experimental dispersion, which turns out to result instead from the ferro-orbital order that is also found instrumental in stabilizing the magnetic order.« less
Nuclear magnetic octupole moment and the hyperfine structure of the 5D32,52 states A. Derevianko,1,2
Blinov, Boris
Nuclear magnetic octupole moment and the hyperfine structure of the 5D3Õ2,5Õ2 states of the Ba+ ion nuclear magnetic moments is presented. The relevant electronic matrix elements are computed relatively unexplored. While octupole moments may be approximated using the nuclear-shell model 1
Multiferroicity and spiral magnetism in FeVO{sub 4} with quenched Fe orbital moments
Daoud-Aladine, A.; Chapon, L. C.; Kundys, B.; Martin, C.; Simon, C.; Radaelli, P. G.; Brown, P. J.
2009-12-01
FeVO{sub 4} has been studied by heat capacity, magnetic susceptibility, electric polarization and single-crystal neutron-diffraction experiments. The triclinic crystal structure is made of S-shaped clusters of six Fe{sup 3+} ions, linked by VO{sub 4}{sup 3-} groups. Two long-range magnetic ordering transitions occur at T{sub N1}=22 K and T{sub N2}=15 K. Both magnetic structures are incommensurate and below T{sub N2}, FeVO{sub 4} becomes weakly ferroelectric coincidentally with the loss of the collinearity of the magnetic structure in a very similar fashion than in the classical TbMnO{sub 3} multiferroic material. However we argue that the symmetry considerations and the mechanisms invoked to explain these properties in TbMnO{sub 3} do not straightforwardly apply to FeVO{sub 4}. First, the magnetic structures, even the collinear structure, are all acentric so that ferroelectricity in FeVO{sub 4} is not correlated with the fact magnetic ordering is breaking inversion symmetry. Regarding the mechanism, FeVO{sub 4} has quenched orbital moments that questions the exact role of the spin-orbit interactions.
Blum, Thomas [Univ. of Connecticut, Storrs, CT (United States); Brookhaven National Lab., Upton, NY (United States); Chowdhury, Saumitra [Univ. of Connecticut, Storrs, CT (United States); Hayakawa, Masashi [Nagoya Univ. (Japan); Nishina Center, RIKEN, Wako, Saitama (Japan); Izubuchi, Taku [Brookhaven National Lab. (BNL), Upton, NY (United States)
2015-01-01
The form factor that yields the light-by-light scattering contribution to the muon anomalous magnetic moment is computed in lattice QCD+QED and QED. A non-perturbative treatment of QED is used and is checked against perturbation theory. The hadronic contribution is calculated for unphysical quark and muon masses, and only the diagram with a single quark loop is computed. Statistically significant signals are obtained. Initial results appear promising, and the prospect for a complete calculation with physical masses and controlled errors is discussed.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Blum, Thomas; Chowdhury, Saumitra; Hayakawa, Masashi; Izubuchi, Taku
2015-01-07
The form factor that yields the light-by-light scattering contribution to the muon anomalous magnetic moment is computed in lattice QCD+QED and QED. A non-perturbative treatment of QED is used and is checked against perturbation theory. The hadronic contribution is calculated for unphysical quark and muon masses, and only the diagram with a single quark loop is computed. Statistically significant signals are obtained. Initial results appear promising, and the prospect for a complete calculation with physical masses and controlled errors is discussed.
Magnetic order in the induced magnetic moment system Pr_{3}In
Fanelli, V. R.; Christianson, Andrew D; Jaime, M.; Thompson, J. D.; Lawrence, J. M.; Suzuki, H. S.
2008-01-01
Pr3In is a single ground state compound which exhibits antiferromagnetic order below 11.4 K due to the exchange induced admixture of crystalline electric field levels. Additional information regarding the complex magnetic behavior of this compound can be gained through application of magnetic fields. We report specific heat and magnetocaloric effect measurements to 15 T and magnetization measurements to 44 T on single crystal samples of Pr3In. A new magnetic phase is revealed above 1.9 T and below 11.4 K.
Alexander J. Silenko
2007-10-02
A buildup of the vertical polarization in the resonant electric dipole moment (EDM) experiment [Y. F. Orlov, W. M. Morse, and Y. K. Semertzidis, Phys. Rev. Lett. 96, 214802 (2006)] is affected by a horizontal electric field in the particle rest frame oscillating at a resonant frequency. This field is defined by the Lorentz transformation of an oscillating longitudinal electric field and a uniform vertical magnetic one. The effect of a longitudinal electric field is significant, while the contribution from a magnetic field caused by forced coherent longitudinal oscillations of particles is dominant. The effect of electric field on the spin dynamics was not taken into account in previous calculations. This effect is considerable and leads to decreasing the EDM effect for the deuteron and increasing it for the proton. The formula for resonance strengths in the EDM experiment has been derived. The spin dynamics has been calculated.
Tinnel, E.P.; Hinze, W.J.
1981-09-01
Total intensity magnetic anomaly data acquired as a supplement to radiometric data in the DOE National Uranium Resource Evaluation (NURE) Program are useful in preparing regional profile and contour maps. Survey-contractor-supplied magnetic anomaly data are subjected to a multiprocess, computer-based procedure which prepares these data for presentation. This procedure is used to produce the following machine plotted maps of National Topographic Map Series quadrangle units at a 1:250,000 scale: (1) profile map of contractor-supplied magnetic anomaly data, (2) profile map of high-cut filtered data with contour levels of each profile marked and annotated on the associated flight track, (3) profile map of critical-point data with contour levels indicated, and (4) contour map of filtered and selected data. These quadrangle maps are supplemented with a range of statistical measures of the data which are useful in quality evaluation.
Zatsiupa, A.A., E-mail: zatsiupa@mail.ru [Belarussian State Technological University, 220030 Minsk (Belarus); Bashkirov, L.A. [Belarussian State Technological University, 220030 Minsk (Belarus); Troyanchuk, I.O. [Scientific and Practical Materials Research Centre of the NAS of Belarus, 220072 Minsk (Belarus); Petrov, G.S. [Belarussian State Technological University, 220030 Minsk (Belarus); Galyas, A.I.; Lobanovsky, L.S.; Truhanov, S.V. [Scientific and Practical Materials Research Centre of the NAS of Belarus, 220072 Minsk (Belarus)
2014-04-01
Magnetic susceptibility for ferrite Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5?950 K. The saturation magnetization is equal to 5.04?{sub B} per formula unit at 5 K in a magnetic field of 10 T. It is found that at 5?300 K the effective magnetic moment of Fe{sup 3+} ions in Bi{sub 25}FeO{sub 39} is equal to 5.82?{sub B}. - Graphical abstract: The dependence of the magnetization (n, ?{sub B}) on the magnetic field for one formula unit of Bi{sub 25}FeO{sub 39} at 5 K. - Highlights: • Magnetic susceptibility for Bi{sub 25}FeO{sub 39} is measured at 5–950 K in the magnetic field of 0.86 T. • It is shown that Bi{sub 25}FeO{sub 39} is paramagnetic in the temperature range 5?950 K. • The saturation magnetization is equal to 5.04?{sub B} per formula unit at 5 K in a magnetic field of 10 T.
T. M. Aliev; K. Azizi; M. Savci
2009-10-11
The electric quadrupole and magnetic octupole moments of the light decuplet baryons are calculated in the framework of the light cone QCD sum rules. The obtained non-vanishing values for the electric quadrupole and magnetic octupole moments of these baryons show nonspherical charge distribution. The sign of electric quadrupole moment is positive for $\\Omega^-$, $\\Xi^{*-}$, $\\Sigma^{*-}$ and negative for $\\Sigma^{*+}$, which correspond to the prolate and oblate charge distributions, respectively. A comparison of the obtained results with the predictions of non-covariant quark model which shows a good consistency between two approaches is also presented. Comparison of the obtained results on the multipole moments of the decuplet baryons containing strange quark with those of $\\Delta$ baryons shows a large SU(3) flavor symmetry breaking.
Magnetization anomaly of Nb3Al strands and instability of Nb3Al Rutherford cables
Yamada, Ryuji; /Fermilab; Kikuchi, Akihiro; /Tsukuba Magnet Lab; Wake, Masayoshi; /KEK, Tsukuba
2006-08-01
Using a Cu stabilized Nb{sub 3}Al strand with Nb matrix, a 30 meter long Nb{sub 3}Al Rutherford cable was made by a collaboration of Fermilab and NIMS. Recently the strand and cable were tested. In both cases instability was observed at around 1.5 Tesla. The magnetization of this Nb{sub 3}Al strand was measured first using a balanced coil magnetometer at 4.2 K. Strands showed an anomalously large magnetization behavior around at 1.6 T, which is much higher than the usual B{sub c2} {approx} 0.5 Tesla (4.2 K) of Nb matrix. This result is compared with the magnetization data of short strand samples using a SQUID magnetometer, in which a flux-jump signal was observed at 0.5 Tesla, but not at higher field. As a possible explanation for this magnetization anomaly, the interfilament coupling through the thin Nb films in the strands is suggested. The instability problem observed in low field tests of the Nb{sub 3}Al Rutherford cables is attributed to this effect.
arXiv:0709.3636v1[hep-ex]23Sep2007 Detecting Neutrino Magnetic Moments with Conducting Loops
arXiv:0709.3636v1[hep-ex]23Sep2007 Detecting Neutrino Magnetic Moments with Conducting Loops Aram the possibility of detecting the magnetic moment using a conducting loop. According to Faraday's Law of Induction, a magnetic dipole passing through a conducting loop induces an electromotive force, or EMF, in the loop. We
B. Plaster
2013-09-22
We propose a new concept for determining the interior magnetic field vector components in neutron electric dipole moment experiments. If a closed three-dimensional boundary surface surrounding the fiducial volume of an experiment can be defined such that its interior encloses no currents or sources of magnetization, each of the interior vector field components and the magnetic scalar potential will satisfy a Laplace equation. Therefore, if either the vector field components or the normal derivative of the scalar potential can be measured on the surface of this boundary, thus defining a Dirichlet or Neumann boundary-value problem, respectively, the interior vector field components or the scalar potential (and, thus, the field components via the gradient of the potential) can be uniquely determined via solution of the Laplace equation. We discuss the applicability of this technique to the determination of the interior magnetic field components during the operating phase of neutron electric dipole moment experiments when it is not, in general, feasible to perform direct in situ measurements of the interior field components. We also study the specifications that a vector field probe must satisfy in order to determine the interior vector field components to a certain precision. The technique we propose here may also be applicable to experiments requiring monitoring of the vector magnetic field components within some closed boundary surface, such as searches for neutron-antineutron oscillations along a flight path or measurements in storage rings of the muon anomalous magnetic moment $g-2$ and the proton electric dipole moment.
Covariant Spectator Theory of np scattering: Deuteron magnetic moment and form factors
Gross, Franz L. [JLAB
2014-06-01
The deuteron magnetic moment is calculated using two model wave functions obtained from 2007 high precision fits to $np$ scattering data. Included in the calculation are a new class of isoscalar $np$ interaction currents which are automatically generated by the nuclear force model used in these fits. After normalizing the wave functions, nearly identical predictions are obtained: model WJC-1, with larger relativistic P-state components, gives 0.863(2), while model WJC-2 with very small $P$-state components gives 0.864(2) These are about 1\\% larger than the measured value of the moment, 0.857 n.m., giving a new prediction for the size of the $\\rho\\pi\\gamma$ exchange, and other purely transverse interaction currents that are largely unconstrained by the nuclear dynamics. The physical significance of these results is discussed, and general formulae for the deuteron form factors, expressed in terms of deuteron wave functions and a new class of interaction current wave functions, are given.
Using magnetic moments to study the nuclear structure of I{>=} 2 states
Torres, D. A.
2013-05-06
The experimental study of magnetic moments for nuclear states near the ground state, I{>=} 2, provides a powerful tool to test nuclear structure models. Traditionally, the use of Coulomb excitation reactions have been utilized to study low spin states, mostly I= 2. The use of alternative reaction channels, such as {alpha} transfer, for the production of radioactive species that, otherwise, will be only produced in future radioactive beam facilities has proved to be an alternative to measure not only excited states with I > 2, but to populate and study long-live radioactive nuclei. This contribution will present the experimental tools and challenges for the use of the transient field technique for the measurement of g factors in nuclear states with I{>=} 2, using Coulomb excitation and {alpha}-transfer reactions. Recent examples of experimental results near the N= 50 shell closure, and the experimental challenges for future implementations with radioactive beams, will be discussed.
Four-flavour leading-order hadronic contribution to the muon anomalous magnetic moment
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Burger, Florian; Feng, Xu; Hotzel, Grit; Jansen, Karl; Univ. of Cyprus, Nicosia; Petschlies, Marcus; Renner, Dru B.
2014-02-24
We present a four-flavour lattice calculation of the leading-order hadronic vacuum polarisation contribution to the anomalous magnetic moment of the muon, a?hvp, arising from quark-connected Feynman graphs. It is based on ensembles featuring Nf=2+1+1 dynamical twisted mass fermions generated by the European Twisted Mass Collaboration (ETMC). Several light quark masses are used in order to yield a controlled extrapolation to the physical pion mass. We employ three lattice spacings to examine lattice artefacts and several different volumes to check for finite-size effects. Including the complete first two generations of quarks allows for a direct comparison with phenomenological determinations of amore »?hvp. The final result involving an estimate of the systematic uncertainty a?hvp=6.74 (21)(18) 10-8 shows a good overall agreement with these computations.« less
Mass and magnetic dipole moment of negative parity heavy baryons with spin--3/2
Azizi, K
2015-01-01
We calculate the mass and residue of the heavy spin--3/2 negative parity baryons with single heavy bottom or charm quark by the help of a two-point correlation function. We use the obtained results to investigate the diagonal radiative transitions among the baryons under consideration. In particular, we compute corresponding transition form factors via light cone QCD sum rules which are then used to obtain the magnetic dipole moments of the heavy spin--3/2 negative parity baryons. We remove the pollutions coming from the positive parity spin--3/2 and positive/negative parity spin--1/2 baryons by constructing sum rules for different Lorentz structures. We compare the results obtained with the existing theoretical predictions.
Mass and magnetic dipole moment of negative parity heavy baryons with spin--3/2
K. Azizi; H. Sundu
2015-06-28
We calculate the mass and residue of the heavy spin--3/2 negative parity baryons with single heavy bottom or charm quark by the help of a two-point correlation function. We use the obtained results to investigate the diagonal radiative transitions among the baryons under consideration. In particular, we compute corresponding transition form factors via light cone QCD sum rules which are then used to obtain the magnetic dipole moments of the heavy spin--3/2 negative parity baryons. We remove the pollutions coming from the positive parity spin--3/2 and positive/negative parity spin--1/2 baryons by constructing sum rules for different Lorentz structures. We compare the results obtained with the existing theoretical predictions.
Granot, Roi
Early India-Australia spreading history revealed by newly detected Mesozoic magnetic anomalies the early spreading history between India and Australia during the Mesozoic breakup of Gondwana. However from Australia with Greater India during initial breakup at ~130 Ma, then rifted from India following
Hall, D.J. (Total Minatome Corporation, Houston, TX (USA))
1990-09-01
The Gulf Coast-East Coast magnetic anomaly extends for at least 4000 km from south-central Texas to offshore Newfoundland as one of the longest continuous tectonic features in North America and a major crustal element of the entire North Atlantic-Gulf Coast region. Analysis of 28 profiles spaced at 100km intervals and four computed models demonstrate that the anomaly may be explained by a thick zone of mafic and ultramafic rocks averaging 13-15 km in depth. The trend of the anomaly closely follows the trend of main Appalachian features: in the Gulf Coast of Louisiana, the anomaly is as far south of the Ouachita front as it is east of the western limit of deformation through the central Appalachians. Because the anomaly continues across well-known continental crust in northern Florida and onshore Texas, it cannot plausibly be ascribed to an edge effect at the boundary of oceanic with continental crustal compositions. The northwest-verging, deep-crustal events discovered in COCORP data from the Ouachitas and Appalachians suggest an analogy with the main suture of the Himalayan orogen in the Tibetan Plateau. In this paper the anomaly is identified with the late Paleozoic Alleghenian megasuture, in which the northwest-verging crustal-detachment surfaces ultimately root.
A. J. Silenko
2006-02-03
The Hamiltonian of relativistic particles with electric and magnetic dipole moments that interact with an electromagnetic field is determined in the Foldy-Wouthuysen representation. Transition to the semiclassical approximation is carried out. The quantum-mechanical and semiclassical equations of spin motion are derived.
Volume 28B, number 5 PHYSICS LETTERS 23 December 1968 MAGNETIC MOMENTS AND SHORT-RANGE CORRELATIONS*
Bertsch George F.
- * This work was supported in part by the U. S. Atomic Energy Commission and the Higgins Scientific Trust Fund seems to work also for lower energy correlations. The calculation of magnetic moments of nuc- lei near, and then discuss the effect of intermediate energy correlations, which can be calculated in second
Wellington da Cruz
1997-10-16
The technique of functional integration over velocities is applied to the calculation of the propagator of a spinning particle with and without anomalous magnetic moment. A representation for the spin factor is obtained in this context for the particle in a constant electromagnetic field. As a by-product, we also obtain a Schwinger representation for the first case.
On the possibility of observing variations of the positron magnetic moment in crystals
Tikhomirov, V.V.
1994-12-01
An analysis of the interaction of e{sup {+-}} with a crossed field revealed that the anomalous magnetic moment {mu}{prime} must differ considerably from its Schwinger value for a field strength E, H {approx} H{sub 0} = m{sup 2}c{sup 3}/e{h_bar} = 4.41{times}10{sup 13}G in the intrinsic reference frame. Such a crossed-field strength can be attained in the intrinsic reference frame of e{sup {+-}} that move along the crystallographic axes. This is due to the fact that the field strength E along the axes is {approx} Z{times}10{sup 10}V/cm (Z is the atomic number of the crystal material), while the field strength E{prime}{approx_equal}H{prime}{approx_equal}{gamma}E in the intrinsic system of e{sup {+-}} that have an energy En {approx} 50 GeV is larger than E by a factor of {gamma} = En/m {approx} 10{sup 5}. The effect of spin rotation in bent crystals can be used to observe the variation of {mu}{prime} in a high-intensity crystal field.
The muon anomalous magnetic moment in the supersymmetric economical 3-3-1 model
D. T. Binh; D. T. Huong; H. N. Long
2015-04-14
We investigate the muon anomalous magnetic moment in the context of the supersymmetric version of the economical 3-3-1 model. We compute the 1-loop contribution of super-partner particles. We show that contribution of superparticle loop becomes significant when \\tan \\gamma is large. We investigate for both small and large values of $\\tan \\gamma$. We find the region of the parameter space where the slepton masses are of a few hundreds GeV is favour by the muon g-2 for small \\tan \\gamma (\\tan \\gamma \\sim 5 ). Numerical estimation gives the mass of supersymmetric particle, the mass of gauginos m_G \\sim 700 GeV and light slepton mass m_{\\tilde{L}} is of order O (100) GeV. When \\tan{\\gamma} is large (\\tan{\\gamma} \\sim 60), the mass of charged slepton m_{\\tilde{L}} and the mass of gauginos m_G\\sim O(1) TeV while the mass of sneutrino \\sim 450 GeV is in the reach of LHC.
The muon anomalous magnetic moment in the supersymmetric economical 3-3-1 model
Binh, D T; Long, H N
2015-01-01
We investigate the muon anomalous magnetic moment in the context of the supersymmetric version of the economical 3-3-1 model. We compute the 1-loop contribution of super-partner particles. We show that contribution of superparticle loop becomes significant when \\tan \\gamma is large. We investigate for both small and large values of $\\tan \\gamma$. We find the region of the parameter space where the slepton masses are of a few hundreds GeV is favour by the muon g-2 for small \\tan \\gamma (\\tan \\gamma \\sim 5 ). Numerical estimation gives the mass of supersymmetric particle, the mass of gauginos m_G \\sim 700 GeV and light slepton mass m_{\\tilde{L}} is of order O (100) GeV. When \\tan{\\gamma} is large (\\tan{\\gamma} \\sim 60), the mass of charged slepton m_{\\tilde{L}} and the mass of gauginos m_G\\sim O(1) TeV while the mass of sneutrino \\sim 450 GeV is in the reach of LHC.
The muon anomalous magnetic moment in the supersymmetric economical 3-3-1 model
D. T. Binh; D. T. Huong; H. N. Long
2015-11-06
We investigate the muon anomalous magnetic moment in the context of the supersymmetric version of the economical 3-3-1 model. We compute the 1-loop contribution of super-partner particles. We show that contribution of superparticle loop becomes significant when \\tan \\gamma is large. We investigate for both small and large values of $\\tan \\gamma$. We find the region of the parameter space where the slepton masses are of a few hundreds GeV is favour by the muon g-2 for small \\tan \\gamma (\\tan \\gamma \\sim 5 ). Numerical estimation gives the mass of supersymmetric particle, the mass of gauginos m_G \\sim 700 GeV and light slepton mass m_{\\tilde{L}} is of order O (100) GeV. When \\tan{\\gamma} is large (\\tan{\\gamma} \\sim 60), the mass of charged slepton m_{\\tilde{L}} and the mass of gauginos m_G\\sim O(1) TeV while the mass of sneutrino \\sim 450 GeV is in the reach of LHC.
Yukawa coupling and anomalous magnetic moment of the muon: An update for the LHC era
Crivellin, Andreas; Girrbach, Jennifer; Nierste, Ulrich
2011-03-01
We study the interplay between a soft muon Yukawa coupling generated radiatively with the trilinear A-terms of the minimal supersymmetric standard model (MSSM) and the anomalous magnetic moment of the muon. In the absence of a tree-level muon Yukawa coupling the lightest smuon mass is predicted to be in the range between 600 GeV and 2200 GeV at 2{sigma}, if the bino mass M{sub 1} is below 1 TeV. Therefore, a detection of a smuon (in conjunction with a sub-TeV bino) at the LHC would directly imply a nonzero muon Yukawa coupling in the MSSM superpotential. Inclusion of slepton flavor mixing could in principle lower the mass of one smuonlike slepton below 600 GeV. However, the experimental bounds on radiative lepton decays instead strengthen the lower mass bound, with larger effects for smaller M{sub 1}, We also extend the analysis to the electron case and find that a light selectron close to the current experimental search limit may prove the MSSM electron Yukawa coupling to be nonzero.
S. Afach; C. A. Baker; G. Ban; G. Bison; K. Bodek; Z. Chowdhuri; M. Daum; M. Fertl; B. Franke; P. Geltenbort; K. Green; M. G. D. van der Grinten; Z. Grujic; P. G. Harris; W. Heil; V. Hélaine; R. Henneck; M. Horras; P. Iaydjiev; S. N. Ivanov; M. Kasprzak; Y. Kermaïdic; K. Kirch; P. Knowles; H. -C. Koch; S. Komposch; A. Kozela; J. Krempel; B. Lauss; T. Lefort; Y. Lemière; A. Mtchedlishvili; O. Naviliat-Cuncic; J. M. Pendlebury; F. M. Piegsa; G. Pignol; P. N. Prashant; G. Quéméner; D. Rebreyend; D. Ries; S. Roccia; P. Schmidt-Wellenburg; N. Severijns; A. Weis; E. Wursten; G. Wyszynski; J. Zejma; J. Zenner; G. Zsigmond
2015-08-03
We report on the measurement of a Larmor frequency shift proportional to the electric-field strength for $^{199}{\\rm Hg}$ atoms contained in a volume permeated with aligned magnetic and electric fields. This shift arises from the interplay between the inevitable magnetic field gradients and the motional magnetic field. The proportionality to electric-field strength makes it apparently similar to an electric dipole moment (EDM) signal, although unlike an EDM this effect is P- and T-conserving. We have used a neutron magnetic resonance EDM spectrometer, featuring a mercury co-magnetometer and an array of external cesium magnetometers, to measure the shift as a function of the applied magnetic field gradient. Our results are in good agreement with theoretical expectations.
Brodsky, Stanley J.; /SLAC; Gardner, Susan; /Kentucky U.; Hwang, Dae Sung; /Sejong U.
2006-01-11
We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n} {approx} -{kappa}{sup p}.
Brodsky, Stanley J. [Stanford Linear Accelerator Center, Stanford University, Stanford, California 94309 (United States); Gardner, Susan [Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506-0055 (United States); Hwang, Dae Sung [Department of Physics, Sejong University, Seoul 143-747 (Korea, Republic of)
2006-02-01
We consider the electric dipole form factor, F{sub 3}(q{sup 2}), as well as the Dirac and Pauli form factors, F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}), of the nucleon in the light-front formalism. We derive an exact formula for F{sub 3}(q{sup 2}) to complement those known for F{sub 1}(q{sup 2}) and F{sub 2}(q{sup 2}). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F{sub 2}(q{sup 2}) and F{sub 3}(q{sup 2}), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, {kappa}{sup n}{approx}-{kappa}{sup p}.
S. J. Brodsky; S. Gardner; D. S. Hwang
2006-02-27
We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock state by Fock state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo the isospin structure of the anomalous magnetic moments, kappa^n ~ - kappa^p.
Atomic moments in Mn_{2}CoAl thin films analyzed by X-ray magnetic circular dichroism
Jamer, M. E.; Assaf, B. A.; Sterbinsky, G. E.; Arena, D. A.; Heiman, D.
2014-12-05
Spin gapless semiconductors are known to be strongly affected by structural disorder when grown epitaxially as thin films. The magnetic properties of Mn_{2}CoAl thin films grown on GaAs (001) substrates are investigated here as a function of annealing. This study investigates the atomic-specific magnetic moments of Mn and Co atoms measured through X-ray magnetic circular dichroism as a function of annealing and the consequent structural ordering. Results indicate that the structural distortion mainly affects the Mn atoms as seen by the reduction of the magnetic moment from its predicted value.
Jian-hua Gao; Qun Wang
2015-04-28
We demonstrate the emergence of the magnetic moment and spin-vorticity coupling of chiral fermions in 4-dimensional Wigner functions. In linear response theory with space-time varying electromagnetic fields, the parity-odd part of the electric conductivity can also be derived which reproduces results of the one-loop and the hard-thermal or hard-dense loop. All these properties show that the 4-dimensional Wigner functions capture comprehensive aspects of physics for chiral fermions in electromagnetic fields.
Jian-hua Gao; Qun Wang
2015-08-26
We demonstrate the emergence of the magnetic moment and spin-vorticity coupling of chiral fermions in 4-dimensional Wigner functions. In linear response theory with space-time varying electromagnetic fields, the parity-odd part of the electric conductivity can also be derived which reproduces results of the one-loop and the hard-thermal or hard-dense loop. All these properties show that the 4-dimensional Wigner functions capture comprehensive aspects of physics for chiral fermions in electromagnetic fields.
Keller, Dustin M. [University of Virginia; Hicks, Kenneth H. [OHIO
2013-05-01
The transition magnetic moments for decuplet-to-octet baryon electromagnetic decays are calculated from the CLAS experimental results and are compared with calculations to first order in the 1/N{sub c} expansion of quantum chromodynamics (QCD) and new U-spin predictions. Using the U-spin predictions for the {Sigma} *{sup 0} --> {Sigma}{sup 0} {gamma} and {Sigma} *{sup +} ? {Sigma}{sup +} {gamma} decays, the SU(3)-forbidden transition {Sigma} *{sup -} ? {Sigma}{sup -} {gamma} is obtained. In addition, the doubly strange baryon radiative decay {Xi} *{sup 0} ? {Xi} {gamma} is predicted using U-spin.
P. G. Harris; J. M. Pendlebury; N. E. Devenish
2013-06-05
Trapped ultracold neutrons (UCN) have for many years been the mainstay of experiments to search for the electric dipole moment (EDM) of the neutron, a critical parameter in constraining scenarios of new physics beyond the Standard Model. Because their energies are so low, UCN preferentially populate the lower region of their physical enclosure, and do not sample uniformly the ambient magnetic field throughout the storage volume. This leads to a substantial increase in the rate of depolarization, as well as to shifts in the measured frequency of the stored neutrons. Consequences for EDM measurements are discussed.
Brodsky, S J; Hwang, D S
2006-01-01
We consider the electric dipole form factor, F_3(q^2), as well as the Dirac and Pauli form factors, F_1(q^2) and F_2(q^2), of the nucleon in the light-front formalism. We derive an exact formula for F_3(q^2) to complement those known for F_1(q^2) and F_2(q^2). We derive the light-front representation of the discrete symmetry transformations and show that time-reversal- and parity-odd effects are captured by phases in the light-front wave functions. We thus determine that the contributions to F_2(q^2) and F_3(q^2), Fock-state by Fock-state, are related, independent of the fundamental mechanism through which CP violation is generated. Our relation is not specific to the nucleon, but, rather, is true of spin-1/2 systems in general, be they lepton or baryon. The empirical values of the anomalous magnetic moments, in concert with empirical bounds on the associated electric dipole moments, can better constrain theories of CP violation. In particular, we find that the neutron and proton electric dipole moments echo ...
Abdel Nasser Tawfik; Niseem Magdy
2015-01-06
Effects of external magnetic field on various properties of the quantum chromodynamics under extreme conditions of temperature and density have been analysed. To this end, we use SU(3) Polyakov linear sigma-model and assume that the external magnetic field eB adds some restrictions to the quarks energy due to the existence of free charges in the plasma phase. In doing this, we apply the Landau theory of quantization. This requires an additional temperature to drive the system through the chiral phase-transition. Accordingly, the dependence of the critical temperature of chiral and confinement phase-transitions on the magnetic field is characterized. Based on this, we have studied the thermal evolution of thermodynamic quantities and the first four higher-order moment of particle multiplicity. Having all these calculations, we have studied the effects of magnetic field on chiral phase-transition. We found that both critical temperature T_c and critical chemical potential increase with increasing the magnetic field eB. Last but not least, the magnetic effects of the thermal evolution of four scalar and four pseudoscalar meson states are studied. We concluded that the meson masses decrease as the temperature increases till T_c. Then, the vacuum effect becomes dominant and rapidly increases with the temperature T. At low T, the scalar meson masses normalized to the lowest Matsubara frequency rapidly decreases as T increases. Then, starting from T_c, we find that the thermal dependence almost vanishes. Furthermore, the meson masses increase with increasing magnetic field. This gives characteristic phase diagram of T vs. external magnetic field $B. At high T, we find that the masses of almost all meson states become temperature independent. It is concluded that the various meson states likely have different T_c's.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Thersleff, Thomas; Rusz, Jan; Rubino, Stefano; Hjörvarsson, Björgvin; Ito, Yasuo; J. Zaluzec, Nestor; Leifer, Klaus
2015-08-17
Understanding the ramifications of reduced crystalline symmetry on magnetic behavior is a critical step in improving our understanding of nanoscale and interfacial magnetism. However, investigations of such effects are often controversial largely due to the challenges inherent in directly correlating nanoscale stoichiometry and structure to magnetic behavior. Here, we describe how to use Transmission Electron Microscope (TEM) to obtain Electron Magnetic Circular Dichroism (EMCD) signals as a function of scattering angle to locally probe the magnetic behavior of thin oxide layers grown on an Fe (1 1 0) surface. Experiments and simulations both reveal a strong dependence of the magneticmore »orbital to spin ratio on its scattering vector in reciprocal space. We exploit this variation to extract the magnetic properties of the oxide cladding layer, showing that it locally may exhibit an enhanced orbital to spin moment ratio. This finding is supported here by both spatially and angularly resolved EMCD measurements, opening up the way for compelling investigations into how magnetic properties are affected by nanoscale features.« less
Tinnel, E.P.; Hinze, W.J.
1981-09-01
Total intensity magnetic anomaly data acquired as a supplement to radiometric data in the DOE National Uranium Resource Evaluation (NURE) Program are useful in preparing regional profile and contour maps. Survey-contractor-supplied magnetic anomaly data are subjected to a multiprocess, computer-based procedure which prepares these data for presentation. This procedure is used to produce the following machine plotted maps of National Topographic Map Series quadrangle units at a 1:250,000 scale: (1) profile map of contractor-supplied magnetic anomaly data, (2) profile map of high-cut filtered data with contour levels of each profile marked and annotated on the associated flight track, (3) profile map of critical-point data with contour levels indicated, and (4) contour map of filtered and selected data. These quadrangle maps are supplemented with a range of statistical measures of the data which are useful in quality evaluation.
H. T. Wong; TEXONO Collaboration
2006-11-14
A search of neutrino magnetic moments was carried out at the Kuo-Sheng Nuclear Power Station at a distance of 28 m from the 2.9 GW reactor core. With a high purity germanium detector of mass 1.06 kg surrounded by scintillating NaI(Tl) and CsI(Tl) crystals as anti-Compton detectors, a detection threshold of 5 keV and a background level of 1 $\\cpd$ near threshold were achieved. Details of the reactor neutrino source, experimental hardware, background understanding and analysis methods are presented. Based on 570.7 and 127.8 days of Reactor ON and OFF data, respectively, at an average Reactor ON electron anti-neutrino flux of $\\rm{6.4 \\times 10^{12} cm^{-2} s^{-1}}$, the limit on the neutrino magnetic moments of $\\rm{\\munuebar < 7.4 \\times 10^{-11} \\mub}$ at 90% confidence level was derived. Indirect bounds on the $\
Enhanced magnetic moment and conductive behavior in NiFe{sub 2}O{sub 4} spinel ultrathin films
Lueders, Ulrike [Institut de Ciencia de Materials de Barcelona, CSIC, Campus de la UAB, 08193 Bellaterra, Catalunya (Spain); LPMC-FRE2686 CNRS-ONERA, 2 avenue Edouard Belin, 31400 Toulouse (France); Bibes, Manuel [Unite Mixte de Physique THALES/CNRS, Domaine de Corbeville, 91404 Orsay (France); Institut d'Electronique Fondamentale, Universite Paris-Sud, 91405 Orsay (France); Bobo, Jean-Francois [LPMC-FRE2686 CNRS-ONERA, 2 avenue Edouard Belin, 31400 Toulouse (France); Cantoni, Matteo; Bertacco, Riccardo [INFM and L-NESS, Dipartimento di Fisica del Politecnico di Milano, via Anzani 52, 22100 Como (Italy); Fontcuberta, Josep [Institut de Ciencia de Materials de Barcelona, CSIC, Campus de la UAB, 08193 Bellaterra, Catalunya (Spain)
2005-04-01
Bulk NiFe{sub 2}O{sub 4} is an insulating ferrimagnet. Here, we report on the epitaxial growth of spinel NiFe{sub 2}O{sub 4} ultrathin films onto SrTiO{sub 3} single crystals. We will show that--under appropriate growth conditions--epitaxial stabilization leads to the formation of a spinel phase with magnetic and electrical properties that radically differ from those of the bulk material: an enhanced magnetic moment (M{sub S})--about 250% larger--and a metallic character. A systematic study of the thickness dependence of M{sub S} allows us to conclude that its enhanced value is due to an anomalous distribution of the Fe and Ni cations among the A and B sites of the spinel structure resulting from the off-equilibrium growth conditions and to interface effects. The relevance of these findings for spinel- and, more generally, oxide-based heterostructures is discussed. We will argue that this novel material could be an alternative ferromagetic-metallic electrode in magnetic tunnel junctions.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Vilmercati, Paolo; Fedorov, Alexei; Bondino, Federica; Offi, Francesco; Panaccione, Giancarlo; Lacovig, Paolo; Simonelli, Laura; McGuire, Michael A.; Sefat, Athena S. M.; Mandrus, David; et al
2012-06-15
A direct and element-specific measurement of the local Fe spin moment has been provided by analyzing the Fe 3s core level photoemission spectra in the parent and optimally doped CeFeAsO??xFx (x = 0, 0.11) and Sr(Fe??xCox)2As2 (x = 0, 0.10) pnictides. The rapid time scales of the photoemission process allowed the detection of large local spin moments fluctuating on a 10?¹? s time scale in the paramagnetic, antiferromagnetic, and superconducting phases, indicative of the occurrence of ubiquitous strong Hund's magnetic correlations. The magnitude of the spin moment is found to vary significantly among different families, 1.3?B in CeFeAsO and 2.1?Bmore »in SrFe?As?. Surprisingly, the spin moment is found to decrease considerably in the optimally doped samples, 0.9?B in CeFeAsO?.??F?.?? and 1.3?B in Sr(Fe?.?Co?.?)?As?. The strong variation of the spin moment against doping and material type indicates that the spin moments and the motion of itinerant electrons are influenced reciprocally in a self-consistent fashion, reflecting the strong competition between the antiferromagnetic superexchange interaction among the spin moments and the kinetic energy gain of the itinerant electrons in the presence of a strong Hund's coupling. By describing the evolution of the magnetic correlations concomitant with the appearance of superconductivity, these results constitute a fundamental step toward attaining a correct description of the microscopic mechanisms shaping the electronic properties in the pnictides, including magnetism and high-temperature superconductivity.« less
Murray, David
1983-01-01
J. Phys. G : Nucl. Phys. 9 (1983) 1125-1 138. Printed in Great Britain The nuclear magnetic moment-capture transitions are deduced and compared with various nuclear models. The angular distribution coefficients S ) ~=0.04( l)pN.Possible single-particle descriptions compatible with this result are suggested. NUCLEAR
Co', G; Anguiano, M; Bernard, R N; Lallena, A M
2015-01-01
We present a model which describes the properties of odd-even nuclei with one nucleon more, or less, with respect to the magic number. In addition to the effects related to the unpaired nucleon, we consider those produced by the excitation of the closed shell core. By using a single particle basis generated with Hartree-Fock calculations, we describe the polarization of the doubly magic-core with Random Phase Approximation collective wave functions. In every step of the calculation, and for all the nuclei considered, we use the same finite-range nucleon-nucleon interaction. We apply our model to the evaluation of electric quadrupole and magnetic dipole moments of odd-even nuclei around oxygen, calcium, zirconium, tin and lead isotopes. Our Random Phase Approximation description of the polarization of the core improves the agreement with experimental data with respect to the predictions of the independent particle model. We compare our results with those obtained in first-order perturbation theory, with those ...
G. Co'; V. De Donno; M. Anguiano; R. N. Bernard; A. M. Lallena
2015-09-08
We present a model which describes the properties of odd-even nuclei with one nucleon more, or less, with respect to the magic number. In addition to the effects related to the unpaired nucleon, we consider those produced by the excitation of the closed shell core. By using a single particle basis generated with Hartree-Fock calculations, we describe the polarization of the doubly magic-core with Random Phase Approximation collective wave functions. In every step of the calculation, and for all the nuclei considered, we use the same finite-range nucleon-nucleon interaction. We apply our model to the evaluation of electric quadrupole and magnetic dipole moments of odd-even nuclei around oxygen, calcium, zirconium, tin and lead isotopes. Our Random Phase Approximation description of the polarization of the core improves the agreement with experimental data with respect to the predictions of the independent particle model. We compare our results with those obtained in first-order perturbation theory, with those produced by Hartree-Fock-Bogolioubov calculations and with those generated within the Landau-Migdal theory of finite Fermi systems. The results of our universal, self-consistent, and parameter free approach have the same quality of those obtained with phenomenological approaches where the various terms of the nucleon-nucleon interaction are adapted to reproduce some specific experimental data. A critical discussion on the validity of the model is presented.
Axion Induced Oscillating Electric Dipole Moments
Christopher T. Hill
2015-04-10
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.
A. L. Barabanov; R. Golub; S. K. Lamoreaux
2005-12-20
The search for particle electric dipole moments represents a most promising way to search for physics beyond the standard model. A number of groups are planning a new generation of experiments using stored gases of various kinds. In order to achieve the target sensitivities it will be necessary to deal with the systematic error resulting from the interaction of the well-known E x v field with magnetic field gradients (often referred to as the geometric phase effect [9,10]). This interaction produces a frequency shift linear in the electric field, mimicking an edm. In this work we introduce an analytic model for the correlation function which determines the behavior of the frequency shift [11], and show in detail how it depends on the operating conditions of the experiment. We also propose a method to directly measure ths correlation function under the exact conditions of a given experiment.
Ruggero Maria Santilli
1997-04-09
We present a new realization of relativistic hadronic me- chanics and its underlying iso-Poincar'e symmetry specifically constructed for nuclear physics which: 1) permits the representation of nucleons as ex- tended, nonspherical and deformable charge distributions with alterable mag- netic moments yet conventional angular momentum and spin; 2) results to be a nonunitary ``completion'' of relativistic quantum mechanics much along the EPR argument; yet 3) is axiom-preserving, thus preserves conventional quantum laws and the axioms of the special relativity. We show that the proposed new formalism permits the apparently first exact representation of the total magnetic moments of new-body nuclei under conventional physical laws. We then point out that, if experimentally confirmed the alterability of the intrinsic characteristics of nucleons would imply new forms of recycling nuclear waste by the nuclear power plants in their own site, thus avoiding its transportation and storage in a (yet unidentified) dumping area. A number of possible, additional basic advances are also indicated, such as: new un- derstanding of nuclear forces with nowel nonlinear, nonlocal and nonunitary terms due to mutual penetrations of the hyperdense nucleons; consequential new models of nuclear structures; new magnetic confinement of the controlled fusion taking into account the possible alterability of the intrinsic magnetic moments of nucleons at the initiation of the fusion process; new sources of en- ergy based on subnuclear processes; and other possible advances. The paper ends with the proposal of three experiments, all essential for the continuation of scientific studies and all of basic character, relatively moderate cost and full feasibility in any nuclear physical laboratory.
Burger, Florian [Humboldt U. Berlin; Feng, Xu [KEK; Hotzel, Grit [Humboldt U. Berlin; Jansen, Karl [DESY; Petschlies, Marcus [The Cyprus Institute; Renner, Dru B. [JLAB
2013-11-01
We present results for the leading order QCD correction to the anomalous magnetic moment of the muon including the first two generations of quarks as dynamical degrees of freedom. Several light quark masses are examined in order to yield a controlled extrapolation to the physical pion mass. We analyse ensembles for three different lattice spacings and several volumes in order to investigate lattice artefacts and finite-size effects, respectively. We also provide preliminary results for this quantity for two flavours of mass-degenerate quarks at the physical value of the pion mass.
Gabrielse, Gerald [Harvard University, Cambridge, Massachusetts, United States
2009-09-01
Remarkably, the famous UW measurement of the electron magnetic moment has stood since 1987. With QED theory, this measurement has determined the accepted value of the fine structure constant. This colloquium is about a new Harvard measurement of these fundamental constants. The new measurement has an uncertainty that is about six times smaller, and it shifts the values by 1.7 standard deviations. One electron suspended in a Penning trap is used for the new measurement, like in the old measurement. What is different is that the lowest quantum levels of the spin and cyclotron motion are resolved, and the cyclotron as well as spin frequencies are determined using quantum jump spectroscopy. In addition, a 0.1 mK Penning trap that is also a cylindrical microwave cavity is used to control the radiation field, to suppress spontaneous emission by more than a factor of 100, to control cavity shifts, and to eliminate the blackbody photons that otherwise stimulate excitations from the cyclotron ground state. Finally, great signal-to-noise for one-quantum transitions is obtained using electronic feedback to realize the first one-particle self-excited oscillator. The new methods may also allow a million times improved measurement of the 500 times small antiproton magnetic moment.
Voicu Dolocan
2015-10-18
By using a Coulomb potential modified by the interaction between the magnetic moments of the electron and proton, we have calculated the energy levels of a hydrogen atom. We have obtained fine structure, hyperfine structure and the Lamb shift. All these are obtained from a simple formula which is a direct solution of the Schroedinger equation. The obtained results are in a good agreement with experimental data. For example, the hyperfine splitting between the energy levels of the states 1S1/2,1 and 1S1/2,0 is of the order of 5.6x10^(-6) eV, which is the source of the famous "21 cm line" which is strongly useful to radio astronomers for tracking hydrogen in the interstellar medium of galaxies. The energy of the states nP1/2 is lower than those of the states nS1/2 (Lamb shift), because in the first case the interaction between the magnetic moments of the proton and electron spins is diminished by the spin-orbit coupling.
Wong, H T; Lin, S T; Lee, F S; Singh, V; Wu, S C; Chang, C Y; Chang, H M; Chen, C P; Chou, M H; Deniz, M; Fang, J M; Hu, C H; Huang, H X; Jon, G C; Kuo, W S; Lai, W P; Lee, S C; Li, J; Liao, H Y; Lin, F K; Lin, S K; Lu, J Q; Sheng, H Y; Su, R F; Tong, W S; Xin, B; Yeh, T R; Yue, Q; Zhou, Z Y; Zhuang, B A
2007-01-01
A search of neutrino magnetic moments was carried out at the Kuo-Sheng Nuclear Power Station at a distance of 28 m from the 2.9 GW reactor core. With a high purity germanium detector of mass 1.06 kg surrounded by scintillating NaI(Tl and CsI(Tl) crystals as anti-Compton detectors, a detection threshold of 5 keV and a background level of 1 $\\cpd$ near threshold were achieved. Details of the reactor neutrino source, experimental hardware, background understanding and analysis methods are presented. Based on 570.7 and 127.8 days of Reactor ON and OFF data, respectively, at an average Reactor ON electron anti-neutrino flux of $\\rm{6.44 \\times 10^{12} cm^{-2} s^{-1}}$, the limit on the neutrino magnetic moments of $\\rm{\\munuebar < 7.2 \\times 10^{-11} \\mub}$ at 90% confidence level was derived. Indirect bounds of the $\
Magnetic order and lattice anomalies in the J{sub 1}-J{sub 2} model system VOMoO{sub 4}
Bombardi, A.; Chapon, L.C.; Margiolaki, I.; Mazzoli, C.; Gonthier, S.; Duc, F.; Radaelli, P.G.
2005-06-01
High-resolution x-ray and neutron powder-diffraction measurements were performed on polycrystalline VOMoO{sub 4}. Below {approx_equal}40 K the system orders in a simple Neel antiferromagnetic state (propagation vector k-vector=0), indicating a dominant role of the nearest-neighbor interactions. The order is three dimensional but the reduced saturated magnetic moment m of 0.41 (1) {mu}{sub B}/V{sup 4+} at 2 K indicates strongly two-dimensional character and enhanced quantum fluctuations. On cooling, there is no evidence of a reduction of the crystal symmetry. However, neutron diffraction indicates an anomalous evolution of the lattice parameters, which can be related to the onset of magnetic correlations.
Blakely, Richard J.; Sherrod, Brian; Weaver, Craig; Wells, Ray E.; Rohay, Alan C.
2014-06-11
Magnetic and gravity data, collected in south-central Washington near the Yakima Fold and Thrust Belt (YFTB) are used to model upper crustal structure, the extent of the late Columbia River Basalt flow named the Ice Harbor member, the vertical conduits (dikes) that the Ice Harbor erupted from, and whether the dikes are offset or affected by faulting on the Wallula Fault zone.
Krakauer, Henry; Zhang, Shiwei
2013-02-21
There are classes of materials that are important to DOE and to the science and technology community, generically referred to as strongly correlated electron systems (SCES), which have proven very difficult to understand and to simulate in a material-specific manner. These range from actinides, which are central to the DOE mission, to transition metal oxides, which include the most promising components of new spin electronics applications as well as the high temperature superconductors, to intermetallic compounds whose heavy fermion characteristics and quantum critical behavior has given rise to some of the most active areas in condensed matter theory. The objective of the CMSN cooperative research team was to focus on the application of these new methodologies to the specific issue of Mott transitions, multi-electron magnetic moments, and dynamical properties correlated materials. Working towards this goal, the W&M team extended its first-principles phaseless auxiliary-field quantum Monte Carlo (AFQMC) method to accurately calculate structural phase transitions and excited states.
Authors A. L. Barabanov; R. Golub; S. K. Lamoreaux
2006-07-17
The search for particle electric dipole moments (edm) represents a most promising way to search for physics beyond the standard model. A number of groups are planning a new generation of experiments using stored gases of various kinds. In order to achieve the target sensitivities it will be necessary to deal with the systematic error resulting from the interaction of the well-known $\\overrightarrow{v}\\times \\overrightarrow{E}$ field with magnetic field gradients (often referred to as the geometric phase effect (Commins, ED; Am. J. Phys. \\QTR{bf}{59}, 1077 (1991), Pendlebury, JM \\QTR{em}{et al;} Phys. Rev. \\QTR{bf}{A70}, 032102 (2004)). This interaction produces a frequency shift linear in the electric field, mimicking an edm. In this work we introduce an analytic form for the velocity auto-correlation function which determines the velocity-position correlation function which in turn determines the behavior of the frequency shift (Lamoreaux, SK and Golub, R; Phys. Rev \\QTR{bf}{A71}, 032104 (2005)) and show how it depends on the operating conditions of the experiment. We also discuss some additional issues.
Baryshevsky, V G
2015-01-01
We study the phenomena of spin rotation and depolarization of high-energy particles in crystals in the range of high energies that will be available at Hadron Collider (LHC) and Future Circular Collider (FCC). It is shown that these phenomena can be used to measure the anomalous magnetic moments of short-lived particles in this range of energies. We also demonstrate that the phenomenon of particle spin depolarization in crystals provides a unique possibility of measuring the anomalous magnetic moment of negatively-charged particles (e.g., beauty baryons), for which the channeling effect is hampered due to far more rapid dechanneling as compared to that for positively-charged particles. Channeling of particles in either straight or bent crystals with polarized nuclei could be used for polarization and the analysis thereof of high-energy particles.
V. G. Baryshevsky
2015-04-25
We study the phenomena of spin rotation and depolarization of high-energy particles in crystals in the range of high energies that will be available at Hadron Collider (LHC) and Future Circular Collider (FCC). It is shown that these phenomena can be used to measure the anomalous magnetic moments of short-lived particles in this range of energies. We also demonstrate that the phenomenon of particle spin depolarization in crystals provides a unique possibility of measuring the anomalous magnetic moment of negatively-charged particles (e.g., beauty baryons), for which the channeling effect is hampered due to far more rapid dechanneling as compared to that for positively-charged particles. Channeling of particles in either straight or bent crystals with polarized nuclei could be used for polarization and the analysis thereof of high-energy particles.
Zuo, Fulin
careful transport and magnetic measurements on single crystals of deuterated - ET 2Cu N CN 2 Br cooling through 80 K will freeze the high temperature magnetic phase to low temperatures and the presence ordering of the chains. In this paper, we report careful transport and magnetic measurements on several
S. K. Lamoreaux; R. Golub
2005-01-25
The search for particle electric dipole moments (edm) is one of the best places to look for physics beyond the standard model because the size of time reversal violation predicted by the standard model is incompatible with present ideas concerning the creation of the Baryon-Antibaryon asymmetry. As the sensitivity of these edm searches increases more subtle systematic effects become important. We develop a general analytical approach to describe a systematic effect recently observed in an electric dipole moment experiment using stored particles \\cite{JMP}. Our approach is based on the relationship between the systematic frequency shift and the velocity autocorrelation function of the resonating particles. Our results, when applied to well-known limiting forms of the correlation function, are in good agreement with both the limiting cases studied in recent work that employed a numerical/heuristic analysis. Our general approach explains some of the surprising results observed in that work and displays the rich behavior of the shift for intermediate frequencies, which has not been previously studied.
Adroja, D. T.; Hillier, A. D.; Kockelmann, W. A.; Anand, V. K.; Stewart, J. R.; Taylor, J. [ISIS Facility, Rutherford Appleton Laboratory, Chilton, Didcot Oxon OX11 0QX (United Kingdom); Deen, P. P. [Institute Laue-Langevin, BP 156, 6 Rue Jules Horowitz, 38042 Grenoble Cedex (France); Strydom, A. M. [Physics Department, University of Johannesburg, P.O. Box 524, Auckland Park 2006 (South Africa); Muro, Y.; Kajino, J.; Takabatake, T. [Department of Quantum Matter, ADSM, and IAMR, Hiroshima University, Higashi-Hiroshima 739-8530 (Japan)
2010-09-01
We have carried out neutron diffraction, muon spin relaxation ({mu}SR), and inelastic neutron scattering (INS) investigations on a polycrystalline sample of CeOs{sub 2}Al{sub 10} to investigate the nature of the phase transition observed near 29 K in the resistivity and heat capacity. Our {mu}SR data clearly reveal coherent frequency oscillations below 28 K, indicating the presence of an internal field at the muon site, which confirms the long-range magnetic ordering of the Ce moment below 28 K. Upon cooling the sample below 15 K, unusual behavior of the temperature-dependent {mu}SR frequencies may indicate either a change in the muon site, consistent with the observation of superstructure reflections in electron diffraction, or a change in the ordered magnetic structure. Neutron diffraction data do not reveal any clear sign of either magnetic Bragg peaks or superlattice reflections. Furthermore, INS measurements clearly reveal the presence of a sharp inelastic excitation near 11 meV between 5 and 26 K, due to opening of a gap in the spin-excitation spectrum, which transforms into a broad response at and above 30 K. The magnitude of the spin gap (11 meV) as derived from the INS peak position agrees very well with the gap value as estimated from the bulk properties.
Isotopic Anomalies in CP Stars: Helium, Mercury, Platinum, and Calcium
C. R. Cowley; S. Hubrig; F. Castelli
2007-11-15
We review the classical observational results for isotopic abundance variations for several elements in CP stars. We concentrate on the "newest" anomaly, in calcium. The cosmically very rare isotope, Ca-48 can rival and even dominate the more common, alpha nuclide, Ca-40. Relevant examples are found in the hot, non-magnetic HgMn stars, and the field horizontal-branch star, Feige 86. The calcium anomaly is also present in cool, magnetic stars, including the notorious HD 101065, Przybylski's star.
Brookhaven National Laboratory - Experiment 821
Energy Accelerator Research Organization, Tsukuba, Ibaraki 3050801, Japan a Department of Physics agreement with the world average. We expect to increase the knowledge of the anomalous magnetic moment to 1 of running will be given, as well as the results of the 1997 run and an outlook to the 1998 and 1999 runs. 2
T. P. Sotiriou; T. A. Apostolatos
2004-10-25
The geometry around a rotating massive body, which carries charge and electrical currents, could be described by its multipole moments (mass moments, mass-current moments, electric moments, and magnetic moments). When a small body is orbiting this massive body, it will move on geodesics, at least for a time interval that is short with respect to the characteristic time of the binary due to gravitational radiation. By monitoring the waves emitted by the small body we are actually tracing the geometry of the central object, and hence, in principle, we can infer all its multipole moments. This paper is a generalization of previous similar results by Ryan. The fact that the electromagnetic moments of spacetime can be measured demonstrates that one can obtain information about the electromagnetic field purely from gravitational wave analysis. Additionally, these measurements could be used as a test of the no-hair theorem for black holes.
Octahedral distortion induced magnetic anomalies in LaMn{sub 0.5}Co{sub 0.5}O{sub 3} single crystals
Manna, Kaustuv Elizabeth, Suja; Anil Kumar, P. S.; Bhadram, Venkata Srinu; Narayana, Chandrabhas
2014-07-28
Single crystals of LaMn{sub 0.5}Co{sub 0.5}O{sub 3} belonging to the ferromagnetic-insulator and distorted perovskite class were grown using a four-mirror optical float zone furnace. The as-grown crystal crystallizes into an orthorhombic Pbnm structure. The spatially resolved 2D Raman scan reveals a strain-induced distribution of transition metal (TM)–oxygen (O) octahedral deformation in the as-grown crystal. A rigorous annealing process releases the strain, thereby generating homogeneous octahedral distortion. The octahedra tilt by reducing the bond angle TM-O-TM, resulting in a decline of the exchange energy in the annealed crystal. The critical behavior is investigated from the bulk magnetization. It is found that the ground state magnetic behavior assigned to the strain-free LaMn{sub 0.5}Co{sub 0.5}O{sub 3} crystal is of the 3D Heisenberg kind. Strain induces mean field-like interaction in some sites, and consequently, the critical exponents deviate from the 3D Heisenberg class in the as-grown crystal. The temperature-dependent Raman scattering study reveals strong spin-phonon coupling and the existence of two magnetic ground states in the same crystal.
Electric-Magnetic Duality and the Heavy Quark Potential
M. Baker
1996-09-05
We use the assumption of electric-magnetic duality to express the heavy quark potential in QCD in terms of a Wilson Loop $W_{eff}(\\Gamma)$ determined by the dynamics of a dual theory which is weakly coupled at long distances. The classical approximation gives the leading contribution to $W_{eff}(\\Gamma)$ and yields a velocity dependent heavy quark potential which for large $R$ becomes linear in $R$, and which for small $R$ approaches lowest order perturbative QCD. The corresponding long distance interaction between color magnetic monopoles is governed by a Yukawa potential. As a consequence the magnetic interaction between the color magnetic moments of the quarks is exponentially damped. The semi-classical corrections to $W_{eff}(\\Gamma)$ due to fluctuations of the classical flux tube should lead to an effective string theory free from the conformal anomaly.
Lesseux, G. G. Urbano, R. R.; Iwamoto, W.; García-Flores, A. F.; Rettori, C.
2014-05-07
The Electron Spin Resonance (ESR) of diluted Er{sup 3+} magnetic ions in Au nanoparticles (NPs) is reported. The NPs were synthesized by reducing chloro triphenyl-phosphine gold(I) and erbium(III) trifluoroacetate. The Er{sup 3+} g-value along with the observed hyperfine splitting indicate that the Er{sup 3+} impurities are in a local cubic symmetry. Furthermore, the Er{sup 3+} ESR spectra show that the exchange interaction between the 4f and the conduction electrons (ce) is absent or negligible in Au{sub 1–x}Er{sub x} NPs, in contrast to the ESR results in bulk Au{sub 1–x}Er{sub x}. Therefore, the nature of this interaction needs to be reexamined at the nano scale range.
Slava G. Turyshev; Viktor T. Toth
2010-08-19
Radio-metric Doppler tracking data received from the Pioneer 10 and 11 spacecraft from heliocentric distances of 20-70 AU has consistently indicated the presence of a small, anomalous, blue-shifted frequency drift uniformly changing with a rate of ~6 x 10^{-9} Hz/s. Ultimately, the drift was interpreted as a constant sunward deceleration of each particular spacecraft at the level of a_P = (8.74 +/- 1.33) x 10^{-10} m/s^2. This apparent violation of the Newton's gravitational inverse-square law has become known as the Pioneer anomaly; the nature of this anomaly remains unexplained. In this review, we summarize the current knowledge of the physical properties of the anomaly and the conditions that led to its detection and characterization. We review various mechanisms proposed to explain the anomaly and discuss the current state of efforts to determine its nature. A comprehensive new investigation of the anomalous behavior of the two Pioneers has begun recently. The new efforts rely on the much-extended set of radio-metric Doppler data for both spacecraft in conjunction with the newly available complete record of their telemetry files and a large archive of original project documentation. As the new study is yet to report its findings, this review provides the necessary background for the new results to appear in the near future. In particular, we provide a significant amount of information on the design, operations and behavior of the two Pioneers during their entire missions, including descriptions of various data formats and techniques used for their navigation and radio-science data analysis. As most of this information was recovered relatively recently, it was not used in the previous studies of the Pioneer anomaly, but it is critical for the new investigation.
Pinpointing the Magnetic Moments of Nuclear Matter
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Utpal Sarkar
2006-06-19
A simple algorithm to calculate the group theory factor entering in anomalies at four and six dimensions for SU(N) and SO(N) groups in terms of the Casimir invariants of their subgroups is presented. Explicit examples of some of the lower dimensional representations of $SU(n), n \\leq 5$ and SO(10) groups are presented, which could be used for model building in four and six dimensions.
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhuravlev, I. A.; Antropov, V. P.; Belashchenko, K. D.
2015-11-16
The origins of the anomalous temperature dependence of magnetocrystalline anisotropy in (Fe1–xCox)2B alloys are elucidated using first-principles calculations within the disordered local moment model. Excellent agreement with experimental data is obtained. The anomalies are associated with the changes in band occupations due to Stoner-like band shifts and with the selective suppression of spin-orbit “hot spots” by thermal spin fluctuations. Under certain conditions, the anisotropy can increase, rather than decrease, with decreasing magnetization. This peculiar electronic mechanisms is in stark contrast to the assumptions of the existing models.
Impurity-induced moments in underdoped cuprates
Khaliullin, G. [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany)] [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany); [Kazan Physicotechnical Institute of the Russian Academy of Sciences, 420029 Kazan (Russia); Kilian, R. [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany)] [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany); Krivenko, S. [Kazan Physicotechnical Institute of the Russian Academy of Sciences, 420029 Kazan (Russia)] [Kazan Physicotechnical Institute of the Russian Academy of Sciences, 420029 Kazan (Russia); Fulde, P. [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany)] [Max-Planck-Institut fuer Physik komplexer Systeme, Noethnitzer Str. 38, D-01187 Dresden (Germany)
1997-11-01
We examine the effect of a nonmagnetic impurity in a two-dimensional spin liquid in the spin-gap phase, employing a drone-fermion representation of spin-1/2 operators. The properties of the local moment induced in the vicinity of the impurity are investigated and an expression for the nuclear-magnetic-resonance Knight shift is derived, which we compare with experimental results. Introducing a second impurity into the spin liquid an antiferromagnetic interaction between the moments is found when the two impurities are located on different sublattices. The presence of many impurities leads to a screening of this interaction as is shown by means of a coherent-potential approximation. Further, the Kondo screening of an impurity-induced local spin by charge carriers is discussed. {copyright} {ital 1997} {ital The American Physical Society}
System for closure of a physical anomaly
Bearinger, Jane P; Maitland, Duncan J; Schumann, Daniel L; Wilson, Thomas S
2014-11-11
Systems for closure of a physical anomaly. Closure is accomplished by a closure body with an exterior surface. The exterior surface contacts the opening of the anomaly and closes the anomaly. The closure body has a primary shape for closing the anomaly and a secondary shape for being positioned in the physical anomaly. The closure body preferably comprises a shape memory polymer.
Subsurface conductive isolation of refraction correlative magnetic signals (SCIRCMS)
Erck, Eric Stephenson
2004-11-15
. This is an independently-derived sequence of anomalous values derived from Global Positioning System (GPS) refracted ranges. Detailed application of the Biot-Savart law provides independent anomaly signals to which the magnetic anomalies correlations show great...
Orbital Anomalies FLORIN DIACU
Diacu, Florin
useless in urban traffic. Newtonian celestial mechanics also continued to develop because they offered other parameters beyond gravita- tion, such as magnetic effects and solar wind. To know the exact sophisticated models could not explain some observations. New phenomena now make the experts wonder whether
Magnetic polarizability of the nucleon
Ragusa, S.
1996-01-01
We derive an expression for the magnetic polarizability of the nucleon, as related to sums of products of its electromagnetic transition moments involving the electric and magnetic dipoles and mean-square radii, as well as the electric quadrupole moment. Two sum rules emerge from the calculation. {copyright} {ital 1995 The American Physical Society.}
ALP hints from cooling anomalies
Giannotti, Maurizio
2015-01-01
We review the current status of the anomalies in stellar cooling and argue that, among the new physics candidates, an axion-like particle would represent the best option to account for the hinted additional cooling.
ALP hints from cooling anomalies
Maurizio Giannotti
2015-08-30
We review the current status of the anomalies in stellar cooling and argue that, among the new physics candidates, an axion-like particle would represent the best option to account for the hinted additional cooling.
Classifying sex biased congenital anomalies
Lubinsky, M.S. [Medical College of Wisconsin and Children`s Hospital, Milwaukee, WI (United States)] [Medical College of Wisconsin and Children`s Hospital, Milwaukee, WI (United States)
1997-03-31
The reasons for sex biases in congenital anomalies that arise before structural or hormonal dimorphisms are established has long been unclear. A review of such disorders shows that patterning and tissue anomalies are female biased, and structural findings are more common in males. This suggests different gender dependent susceptibilities to developmental disturbances, with female vulnerabilities focused on early blastogenesis/determination, while males are more likely to involve later organogenesis/morphogenesis. A dual origin for some anomalies explains paradoxical reductions of sex biases with greater severity (i.e., multiple rather than single malformations), presumably as more severe events increase the involvement of an otherwise minor process with opposite biases to those of the primary mechanism. The cause for these sex differences is unknown, but early dimorphisms, such as differences in growth or presence of H-Y antigen, may be responsible. This model provides a useful rationale for understanding and classifying sex-biased congenital anomalies. 42 refs., 7 tabs.
Schwarz, Dominik J; Huterer, Dragan; Starkman, Glenn D
2015-01-01
Several unexpected features have been observed in the microwave sky at large angular scales, both by WMAP an by Planck. Among those features is a lack of both variance and correlation on the largest angular scales, alignment of the lowest multipole moments with one another and with the motion and geometry of the Solar System, a hemispherical power asymmetry or dipolar power modulation, a preference for odd parity modes and an unexpectedly large cold spot in the Southern hemisphere. The individual p-values of the significance of these features are in the per mille to per cent level, when compared to the expectations of the best-fit inflationary $\\Lambda$CDM model. Some pairs of those features are demonstrably uncorrelated, increasing their combined statistical significance and indicating a significant detection of CMB features at angular scales larger than a few degrees on top of the standard model. Despite numerous detailed investigations, we still lack a clear understanding of these large-scale features, whi...
Magnetic and Electric Dipole Constraints on Extra Dimensions and Magnetic Fluxes
Aaron J. Roy; Myron Bander
2008-05-10
The propagation of charged particles and gauge fields in a compact extra dimension contributes to $g-2$ of the charged particles. In addition, a magnetic flux threading this extra dimension generates an electric dipole moment for these particles. We present constraints on the compactification size and on the possible magnetic flux imposed by the comparison of data and theory of the magnetic moment of the muon and from limits on the electric dipole moments of the muon, neutron and electron.
Contamination of Dark Matter Experiments from Atmospheric Magnetic Dipoles
A. Bueno; M. Masip; P. Sánchez-Lucas; N. Setzer
2013-10-14
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.
Seasonal persistence of midlatitude total ozone anomalies
Wirosoetisno, Djoko
Seasonal persistence of midlatitude total ozone anomalies Article Published Version Fioletov, V. E. and Shepherd, T. G. (2003) Seasonal persistence of midlatitude total ozone anomalies. Geophysical Research persistence of midlatitude total ozone anomalies Vitali E. Fioletov Meteorological Service of Canada, Toronto
Plasticity-Induced Magnetization in Amorphous Magnetic Solids
H. George E. Hentschel; Itamar Procaccia; Bhaskar Sen Gupta
2013-10-15
Amorphous magnetic solids, like metallic glasses, exhibit a novel effect: the growth of magnetic order as a function of mechanical strain under athermal conditions in the presence of a magnetic field. The magnetic moment increases in steps whenever there is a plastic event. Thus plasticity induces the magnetic ordering, acting as the effective noise driving the system towards equilibrium. We present results of atomistic simulations of this effect in a model of a magnetic amorphous solid subjected to pure shear and a magnetic field. To elucidate the dependence on external strain and magnetic field we offer a mean-field theory that provides an adequate qualitative understanding of the observed phenomenon.
Muonic Hydrogen and the Third Zemach Moment
J. L. Friar; I. Sick
2005-08-12
We determine the third Zemach moment of hydrogen (_(2)) using only the world data on elastic electron-proton scattering. This moment dominates the O (Z alpha)^5 hadronic correction to the Lamb shift in muonic atoms. The resulting moment, _(2) = 2.71(13) fm^3, is somewhat larger than previously inferred values based on models. The contribution of that moment to the muonic hydrogen 2S level is -0.0247(12) meV.
The Fourth Moment in Luby's Distribution
The Fourth Moment in Luby's Distribution Devdatt P. Dubhashi Grammati E. Pantziou Paul G. Spirakis Christos D. Zaroliagis MPI{I{95{1-019 August 1995 0 #12;The Fourth Moment in Luby's Distribution Devdatt P properties of Luby's space. More precisely, we analyze the fourth moment and prove an interesting technical
Electromagnetic acceleration of permanent magnets
Dolya, S N
2015-01-01
We consider the acceleration of the permanent magnets, consisting of neodymium iron boron by means of the running magnetic field gradient. It is shown that the specific magnetic moment per nucleon in neodymium iron boron is determined by the remained magnetization of the substance. The maximum accessable gradient of the magnetic field accelerating the permanent magnets is determined by the coercive force thirty kilogauss. For the neodymium iron boron magnets this gradient is equal to twenty kilogauss divided by one centimeter. The finite velocity of the magnets six kilometers per second, the length of acceleration is six hundred thirty-seven meters.
Thomas-BMT equation generalized to electric dipole moments and field gradients
Metodiev, Eric M
2015-01-01
An expression is presented for the relativistic equations of motion, including field gradients, of a particle and its spin with electric and magnetic dipole moments aligned along the spin axis. An electromagnetic duality transformation is used to generalize a Thomas-BMT equation with gradient terms. Corrections to particle dynamics in storage rings for precision $(g-2)$ and electric dipole moment measurements are calculated, and applications to precision particle tracking programs are considered.
Kravtsov, V.E., E-mail: kravtsov@ictp.it [Abdus Salam International Centre for Theoretical Physics, P.O. Box 586, 34100 Trieste (Italy); Landau Institute for Theoretical Physics, 2 Kosygina st., 117940 Moscow (Russian Federation); Yudson, V.I., E-mail: yudson@isan.troitsk.ru [Institute for Spectroscopy, Russian Academy of Sciences, 142190 Troitsk, Moscow reg. (Russian Federation)
2011-07-15
Highlights: > Statistics of normalized eigenfunctions in one-dimensional Anderson localization at E = 0 is studied. > Moments of inverse participation ratio are calculated. > Equation for generating function is derived at E = 0. > An exact solution for generating function at E = 0 is obtained. > Relation of the generating function to the phase distribution function is established. - Abstract: The one-dimensional (1d) Anderson model (AM), i.e. a tight-binding chain with random uncorrelated on-site energies, has statistical anomalies at any rational point f=(2a)/({lambda}{sub E}) , where a is the lattice constant and {lambda}{sub E} is the de Broglie wavelength. We develop a regular approach to anomalous statistics of normalized eigenfunctions {psi}(r) at such commensurability points. The approach is based on an exact integral transfer-matrix equation for a generating function {Phi}{sub r}(u, {phi}) (u and {phi} have a meaning of the squared amplitude and phase of eigenfunctions, r is the position of the observation point). This generating function can be used to compute local statistics of eigenfunctions of 1d AM at any disorder and to address the problem of higher-order anomalies at f=p/q with q > 2. The descender of the generating function P{sub r}({phi}){identical_to}{Phi}{sub r}(u=0,{phi}) is shown to be the distribution function of phase which determines the Lyapunov exponent and the local density of states. In the leading order in the small disorder we derived a second-order partial differential equation for the r-independent ('zero-mode') component {Phi}(u, {phi}) at the E = 0 (f=1/2 ) anomaly. This equation is nonseparable in variables u and {phi}. Yet, we show that due to a hidden symmetry, it is integrable and we construct an exact solution for {Phi}(u, {phi}) explicitly in quadratures. Using this solution we computed moments I{sub m} = N< vertical bar {psi} vertical bar {sup 2m}> (m {>=} 1) for a chain of the length N {yields} {infinity} and found an essential difference between their m-behavior in the center-of-band anomaly and for energies outside this anomaly. Outside the anomaly the 'extrinsic' localization length defined from the Lyapunov exponent coincides with that defined from the inverse participation ratio ('intrinsic' localization length). This is not the case at the E = 0 anomaly where the extrinsic localization length is smaller than the intrinsic one. At E = 0 one also observes an anomalous enhancement of large moments compatible with existence of yet another, much smaller characteristic length scale.
Spurious Anomalies in Dimensional Renormalization
T. L. Trueman
1995-04-17
A set of procedures is given for avoiding the spurious anomalies that are generated when the 't Hooft - Veltman definition of gamma5 is used in conjunction with renormalization by minimal subtraction. These procedures are derived from the standard procedure, which requires in addition various finite renormalizations to remove spurious violations of chiral symmetry. They apply to open fermion lines, including flavor changing currents, to closed fermion loops, including those which contain true anomalous currents, and to anomalous loops connected to open fermion lines, to all orders in QCD.
Galilean Anomalies and Their Effect on Hydrodynamics
Akash Jain
2015-09-18
We extend the null background construction of [arXiv:1505.05677,arXiv:1509.04718] to include torsion and a conserved spin current, and use it to study gauge and gravitational anomalies in Galilean theories coupled to torsional Newton-Cartan backgrounds. We establish that the relativistic anomaly inflow mechanism with an appropriately modified anomaly polynomial, can be used to generate these anomalies. Similar to relativistic case, we find that Galilean anomalies also survive only in even dimensions. Further, these anomalies only effect the gauge and rotational symmetries of a Galilean theory; in particular the Milne boost symmetry remains non-anomalous. We also extend the transgression machinery used in relativistic fluids to fluids on null backgrounds, and use it to determine how these anomalies affect the constitutive relations of a Galilean fluid. Unrelated to Galilean fluids, we propose an analogue of the off-shell second law of thermodynamics for relativistic fluids introduced by [arXiv:1106.0277], to include torsion and a conserved spin current in Vielbein formalism. Interestingly, we find that even in absense of spin and torsion the entropy currents in two formalisms are different; while the usual entropy current gets a contribution from gravitational anomaly, the entropy current in Vielbein formalism does not have any anomaly induced part.
Quantum chaos in hydrogen: Dynamical-group approach and a resonance anomaly in the Brody parameter
Hegerfeldt, G.C.; Henneberg, R. (Institut fuer Theoretische Physik, Universitaet Goettingen, West Germany (DE))
1990-01-15
We apply the dynamical group of the hydrogen atom to level statistics of hydrogen in strong magnetic fields and study the transition region between regularity and chaos in detail. We find a resonancelike anomaly in the Brody parameter which coincides to an amazing accuracy with the appearance of a low rational winding number.
Semiclassical bounds in magnetic bottles
Diana Barseghyan; Pavel Exner; Hynek Kovarik; Timo Weidl
2015-01-13
The aim of the paper is to derive spectral estimates into several classes of magnetic systems. They include three-dimensional regions with Dirichlet boundary as well as a particle in $\\mathbb{R}^3$ confined by a local change of the magnetic field. We establish two-dimensional Berezin-Li-Yau and Lieb-Thirring-type bounds in the presence of magnetic fields and, using them, get three-dimensional estimates for the eigenvalue moments of the corresponding magnetic Laplacians.
Axisymmetric stationary solutions with arbitrary multipole moments
Thomas Bäckdahl
2006-12-07
In this paper, the problem of finding an axisymmetric stationary spacetime from a specified set of multipole moments, is studied. The condition on the multipole moments, for existence of a solution, is formulated as a convergence condition on a power series formed from the multipole moments. The methods in this paper can also be used to give approximate solutions to any order as well as estimates on each term of the resulting power series.
Muon Anomaly and Dark Parity Violation
Hooman Davoudiasl; Hye-Sung Lee; William J. Marciano
2012-07-06
The muon anomalous magnetic moment exhibits a 3.6 \\sigma discrepancy between experiment and theory. One explanation requires the existence of a light vector boson, Z_d (the dark Z), with mass 10 - 500 MeV that couples weakly to the electromagnetic current through kinetic mixing. Support for such a solution also comes from astrophysics conjectures regarding the utility of a U(1)_d gauge symmetry in the dark matter sector. In that scenario, we show that mass mixing between the Z_d and ordinary Z boson introduces a new source of "dark" parity violation which is potentially observable in atomic and polarized electron scattering experiments. Restrictive bounds on the mixing (m_{Z_d} / m_Z) \\delta are found from existing atomic parity violation results, \\delta^2 < 2 x 10^{-5}. Combined with future planned and proposed polarized electron scattering experiments, a sensitivity of \\delta^2 ~ 10^{-6} is expected to be reached, thereby complementing direct searches for the Z_d boson.
Surface magnetism of Gd(0001): Evidence of ferromagnetic coupling to bulk
Mulhollan, G.A.; Garrison, K.; Erskine, J.L. )
1992-11-30
Previous polarized electron experiments and recent {ital ab} {ital initio} calculations suggest that the surface layer magnetic moments of Gd(0001) are antiferromagnetically coupled to the bulk magnetic moments. Spin-polarized photoemission data are presented which show that the spin polarization of the magnetic surface state and the surface 4{ital f} states of Gd(0001) are coupled ferromagnetically to the bulk magnetic moment.
Pair creation in an electric flux tube and chiral anomaly
Iwazaki, Aiichi [International Economics and Politics, Nishogakusha University, Ohi Kashiwa, Chiba 277-8585 (Japan)
2009-11-15
Using the chiral anomaly, we discuss the pair creation of massless fermions under the effect of a magnetic field B-vector when an electric flux tube E-vector parallel to B-vector is switched on. The tube is axially symmetric and infinitely long. For the constraint B>>E, we can analytically obtain the spatial and temporal behaviors of the number density of the fermions, the azimuthal magnetic field generated by the fermions, and so on. We find that the lifetime t{sub c} of the electric field becomes shorter as the width of the tube becomes narrower. Applying it to the plasma in high-energy heavy-ion collisions, we find that the color electric field decays quickly such that t{sub c}{approx_equal}Q{sub s}{sup -1}, in which Q{sub s} is the saturation momentum.
NEUTRON ELECTRIC-DIPOLE MOMENT, ULTRACOLD NEUTRONS
NEUTRON ELECTRIC-DIPOLE MOMENT, ULTRACOLD NEUTRONS AND POLARIZED 3He R. GOLUB~and Steve K REPORTS (Review Section of Physics Letters) 237, No. 1(1994)1--62. PHYSICS REPORTS North-Holland Neutron electric-dipole moment, ultracold neutrons and polarized 3He R. Goluba and Steve K. Lamoreauxb a
Galilean Anomalies and Their Effect on Hydrodynamics
Jain, Akash
2015-01-01
We extend the null background construction of [arXiv:1505.05677,arXiv:1509.04718] to include torsion and a conserved spin current, and use it to study gauge and gravitational anomalies in Galilean theories coupled to torsional Newton-Cartan backgrounds. We establish that the relativistic anomaly inflow mechanism with an appropriately modified anomaly polynomial, can be used to generate these anomalies. Similar to relativistic case, we find that Galilean anomalies also survive only in even dimensions. Further, these anomalies only effect the gauge and rotational symmetries of a Galilean theory; in particular the Milne boost symmetry remains non-anomalous. We also extend the transgression machinery used in relativistic fluids to fluids on null backgrounds, and use it to determine how these anomalies affect the constitutive relations of a Galilean fluid. Unrelated to Galilean fluids, we propose an analogue of the off-shell second law of thermodynamics for relativistic fluids introduced by [arXiv:1106.0277], to i...
Anomaly Detection in Dynamic Networks
Turcotte, Melissa
2014-10-14
Anomaly detection in dynamic communication networks has many important security applications. These networks can be extremely large and so detecting any changes in their structure can be computationally challenging; hence, computationally fast, parallelisable methods for monitoring the network are paramount. For this reason the methods presented here use independent node and edge based models to detect locally anomalous substructures within communication networks. As a first stage, the aim is to detect changes in the data streams arising from node or edge communications. Throughout the thesis simple, conjugate Bayesian models for counting processes are used to model these data streams. A second stage of analysis can then be performed on a much reduced subset of the network comprising nodes and edges which have been identified as potentially anomalous in the first stage. The first method assumes communications in a network arise from an inhomogeneous Poisson process with piecewise constant intensity. Anomaly detection is then treated as a changepoint problem on the intensities. The changepoint model is extended to incorporate seasonal behavior inherent in communication networks. This seasonal behavior is also viewed as a changepoint problem acting on a piecewise constant Poisson process. In a static time frame, inference is made on this extended model via a Gibbs sampling strategy. In a sequential time frame, where the data arrive as a stream, a novel, fast Sequential Monte Carlo (SMC) algorithm is introduced to sample from the sequence of posterior distributions of the change points over time. A second method is considered for monitoring communications in a large scale computer network. The usage patterns in these types of networks are very bursty in nature and don’t fit a Poisson process model. For tractable inference, discrete time models are considered, where the data are aggregated into discrete time periods and probability models are fitted to the communication counts. In a sequential analysis, anomalous behavior is then identified from outlying behavior with respect to the fitted predictive probability models. Seasonality is again incorporated into the model and is treated as a changepoint model on the transition probabilities of a discrete time Markov process. Second stage analytics are then developed which combine anomalous edges to identify anomalous substructures in the network.
Recursive Sketching For Frequency Moments
Braverman, Vladimir
2010-01-01
In a ground-breaking paper, Indyk and Woodruff (STOC 05) showed how to compute $F_k$ (for $k>2$) in space complexity $O(\\mbox{\\em poly-log}(n,m)\\cdot n^{1-\\frac2k})$, which is optimal up to (large) poly-logarithmic factors in $n$ and $m$, where $m$ is the length of the stream and $n$ is the upper bound on the number of distinct elements in a stream. The best known lower bound for large moments is $\\Omega(\\log(n)n^{1-\\frac2k})$. A follow-up work of Bhuvanagiri, Ganguly, Kesh and Saha (SODA 2006) reduced the poly-logarithmic factors of Indyk and Woodruff to $O(\\log^2(m)\\cdot (\\log n+ \\log m)\\cdot n^{1-{2\\over k}})$. Further reduction of poly-log factors has been an elusive goal since 2006, when Indyk and Woodruff method seemed to hit a natural "barrier." Using our simple recursive sketch, we provide a different yet simple approach to obtain a $O(\\log(m)\\log(nm)\\cdot (\\log\\log n)^4\\cdot n^{1-{2\\over k}})$ algorithm for constant $\\epsilon$ (our bound is, in fact, somewhat stronger, where the $(\\log\\log n)$ term c...
Transport moments beyond the leading order
Gregory Berkolaiko; Jack Kuipers
2011-07-11
For chaotic cavities with scattering leads attached, transport properties can be approximated in terms of the classical trajectories which enter and exit the system. With a semiclassical treatment involving fine correlations between such trajectories we develop a diagrammatic technique to calculate the moments of various transport quantities. Namely, we find the moments of the transmission and reflection eigenvalues for systems with and without time reversal symmetry. We also derive related quantities involving an energy dependence: the moments of the Wigner delay times and the density of states of chaotic Andreev billiards, where we find that the gap in the density persists when subleading corrections are included. Finally, we show how to adapt our techniques to non-linear statistics by calculating the correlation between transport moments. In each setting, the answer for the $n$-th moment is obtained for arbitrary $n$ (in the form of a moment generating function) and for up to the three leading orders in terms of the inverse channel number. Our results suggest patterns which should hold for further corrections and by matching with the low order moments available from random matrix theory we derive likely higher order generating functions.
The electric charge and magnetic moment of neutral fundamental particles
Kaushik Bhattacharya
2009-05-27
The article focuses on the issue of the two definitions of charge, mainly the gauge charge and the effective charge of fundamental particles. Most textbooks on classical electromagnetism and quantum field theory only works with the gauge charges while the concept of the induced charge remains unattended. In this article it has been shown that for intrinsically charged particles both of the charges remain the same but there can be situations where an electrically neutral particle picks up some electrical charge from its plasma surrounding. The physical origin and the scope of application of the induced charge concept has been briefly discussed in the article.
Anomalous magnetic moments of free and bound leptons
Pachucki, Krzysztof
]. An almost simultaneous calculation by Schwinger [2] showed how the electron self-interaction explains. Jentschura. MaxÂPlanckÂInstitut fÂ¨ur Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany. e-mail: Ulrich.Jentschura@mpi-hd.mpg to know this part with the maximum possible accuracy. Schwinger's calculation included a single virtual
LIMIT ON THE MUON NEUTRINO MAGNETIC MOMENT AND A MEASUREMENT
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CP-violating CFT and trace anomaly
Yu Nakayama
2012-01-26
It is logically possible that the trace anomaly in four dimension includes the Hirzebruch-Pontryagin density in CP violating theories. Although the term vanishes at free conformal fixed points, we realize such a possibility in the holographic renormalization group and show that it is indeed possible. The Hirzebruch-Pontryagin term in the trace anomaly may serve as a barometer to understand how much CP is violated in conformal field theories.
Axion Induced Oscillating Electric Dipole Moment of the Electron
Christopher T. Hill
2015-09-28
The axion electromagnetic anomaly induces an oscillating electric dipole for the electron 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 constant limit. We give a detailed study of this phenomenon via the interaction of the cosmic axion, through the electromagnetic anomaly, with particular emphasis on the decoupling limit of the axion, $\\partial_t a(t)\\propto m_a \\rightarrow 0$. The general form of the action involves a local contact interaction and a nonlocal contribution that enforces the decoupling limit. We derive the effective action in the Pauli-Schroedinger non-relativistic formalism, and in Georgi's heavy quark formalism adapted to the "heavy electron" (heavy compared to $m_a$). We compute the electric dipole radiation emitted by stationary electrons, and we discuss a number of experimental configurations that may yield detectable signals. Phased array radiators with $N^2$ unit cell magnetic elements may have advantages over resonant cavities that exploit large $Q$, since we can design toward $N^2 >> Q$.
TIMING NOISE IN PULSARS AND MAGNETARS AND THE MAGNETOSPHERIC MOMENT OF INERTIA
Tsang, David; Gourgouliatos, Konstantinos N. E-mail: kostasg@physics.mcgill.ca
2013-08-10
We examine timing noise in both magnetars and regular pulsars, and find that there exists a component of the timing noise ({sigma}{sub TN}) with strong magnetic field dependence ({sigma}{sub TN}{approx}B{sub o}{sup 2}{Omega}T{sup 3/2}) above B{sub o} {approx} 10{sup 12.5} G. The dependence of the timing noise floor on the magnetic field is also reflected in the smallest observable glitch size. We find that magnetospheric torque variation cannot explain this component of timing noise. We calculate the moment of inertia of the magnetic field outside of a neutron star and show that this timing noise component may be due to variation of this moment of inertia, and could be evidence of rapid global magnetospheric variability.
Toroidal Dipole Moment of a Massless Neutrino
Cabral-Rosetti, L. G.; Mondragon, M.; Perez, E. Reyes
2009-04-20
We obtain the toroidal dipole moment of a massless neutrino {tau}{sub v{sub I}}{sup M} using the results for the anapole moment of a massless Dirac neutrino a{sub v{sub I}}{sup D}, which was obtained in the context of the Standard Model of the electroweak interactions (SM)SU(2){sub L} x U(1){sub Y}.
Neutron Electric Dipole Moments from Beyond the Standard Model...
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Neutron Electric Dipole Moments from Beyond the Standard Model Physics Citation Details In-Document Search Title: Neutron Electric Dipole Moments from Beyond the Standard Model...
CFD Combustion Modeling with Conditional Moment Closure using...
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Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry CFD Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry A method is...
The influence of Nd dopants on spin and orbital moments in Nd-doped permalloy thin films
Luo, Chen Zhang, Wen E-mail: yazhai@seu.edu.cn; Zhai, Ya E-mail: yazhai@seu.edu.cn; Wong, P. K. J.; You, Biao; Du, Jun; Zhai, Hongru
2014-08-25
Magnetic properties of Nd{sub X}-Ni{sub 80}Fe{sub 20(1?X)} thin films have been investigated using x-ray absorption spectroscopy and x-ray magnetic circular dichroism (XMCD) at room temperature. With the Nd concentration increasing, the ratio of orbital-to-spin moment of Ni and Fe increases significantly, indicating that the spin-orbit coupling in permalloy thin films is enhanced due to the Nd impurities. The spin and orbital moments have been obtained by the sum rules analysis, which shows that the Nd impurities lead to a strong dispersion of spin moments of Fe and Ni while have no effect on orbital moments in Nd-doped permalloy thin films. Element-specific XMCD hysteresis loops suggest an antiferromagnetic coupling between the magnetic moments of Nd and permalloy at room temperature. The static magnetic properties have been studied by vibrating sample magnetometer for comparison, which shows a nice agreement with the XMCD results.
Anderson localization and Brewster anomalies in photonic disordered quasiperiodic lattices
Reyes-Gomez, E.; Bruno-Alfonso, A.; Cavalcanti, S. B.; Oliveira, L. E.
2011-09-15
A comprehensive study of the properties of light propagation through one-dimensional photonic disordered quasiperiodic superlattices, composed of alternating layers with random thicknesses of air and a dispersive metamaterial, is theoretically performed. The superlattices consist of the successive stacking of N quasiperiodic Fibonacci or Thue-Morse heterostructures. The width of the slabs in the photonic superlattice may randomly fluctuate around its mean value, which introduces a structural disorder into the system. It is assumed that the left-handed layers have a Drude-type dispersive response for both the dielectric permittivity and magnetic permeability, and Maxwell's equations are solved for oblique incidence by using the transfer-matrix formalism. The influence of both quasiperiodicity and structural disorder on the localization length and Brewster anomalies are thoroughly discussed.
Theoretical investigation of the magnetic structure in YBa_2Cu_3O_6
Ekkehard Krüger
2006-08-07
As experimentally well established, YBa_2Cu_3O_6 is an antiferromagnet with the magnetic moments lying on the Cu sites. Starting from this experimental result and the assumption, that nearest-neighbor Cu atoms within a layer have exactly antiparallel magnetic moments, the orientation of the magnetic moments has been determined within a nonadiabatic extension of the Heisenberg model of magnetism, called nonadiabatic Heisenberg model. Within this group-theoretical model there exist four stable magnetic structures in YBa_2Cu_3O_6, two of them are obviously identical with the high- and low-temperature structure established experimentally. However, not all the magnetic moments which appear to be antiparallel in neutron-scattering experiments are exactly antiparallel within this group-theoretical model. Furthermore, within this model the magnetic moments are not exactly perpendicular to the orthorhombic c axis.
Spin and orbital moments in actinide compounds (invited)
Lebech, B. ); Wulff, M.; Lander, G.H. )
1991-04-15
The extended spatial distribution of both the transition-metal 3{ital d} electrons and the actinide 5{ital f} electrons results in a strong interaction between these electron states when the relevant elements are alloyed. A particular interesting feature of this hybridization, which is predicted by single-electron band-structure calculations, is that the orbital moments of the actinide 5{ital f} electrons are considerably reduced from the values anticipated by a simple application of Hund's rules. To test these ideas, and thus to obtain a measure of the hybridization, we have performed a series of neutron scattering experiments designed to determine the magnetic moments at the actinide and transition-metal sublattice sites in compounds such as UFe{sub 2}, NpCo{sub 2}, and PuFe{sub 2} and to separate the spin and orbital components at the actinide sites. The results show, indeed, that the ratio of the orbital to spin moment is reduced as compared to the free-ion expectations. In addition there is qualitative agreement with theory, although the latter predicts values of both components that are larger than those found by experiment. Because {bold L} and {bold S} are opposed in the light actinides, and {ital L} is usually greater than {ital S}, the reduction of {ital L} can result in a situation for which {ital L}{minus}{ital S}{congruent}0. This almost occurs in UFe{sub 2}. However, neutrons are capable of observing the individual components at finite wave vector ({bold Q}), although the total component (observed at {bold Q}={bold 0}) may indeed be close to zero.
Density variations and anomalies in palladium compacts
Back, D.; Jones, T.; Ransick, M.; Walburg, T.; Werkmeister, D.
1992-05-14
Low-density compacts of palladium powder have relative densities of about 30{plus minus}10% TD. The variations in density are of concern for operations such as chemical/hydrogen pump systems because heat, mass, and momentum transport properties can be affected. Variations in density result from the inherent nature and interacting forces of UASA compaction of powder in cylinders. In addition to these expected variations, discontinuous density anomalies, such as cracks or high density ridges, are also found. An anomaly of particular concern was found to resemble a steer's head.'' it is a symmetrical region of low density located at or near the center of a compact. Typically, this region is surrounded by a band of high density, compacted palladium that sometimes exceeds the density of the surrounding compact matrix by a factor of three. This report examines these density variations and anomalies both theoretically and empirically.
Density variations and anomalies in palladium compacts
Back, D.; Jones, T.; Ransick, M.; Walburg, T.; Werkmeister, D.
1992-05-14
Low-density compacts of palladium powder have relative densities of about 30{plus_minus}10% TD. The variations in density are of concern for operations such as chemical/hydrogen pump systems because heat, mass, and momentum transport properties can be affected. Variations in density result from the inherent nature and interacting forces of UASA compaction of powder in cylinders. In addition to these expected variations, discontinuous density anomalies, such as cracks or high density ridges, are also found. An anomaly of particular concern was found to resemble a ``steer`s head.`` it is a symmetrical region of low density located at or near the center of a compact. Typically, this region is surrounded by a band of high density, compacted palladium that sometimes exceeds the density of the surrounding compact matrix by a factor of three. This report examines these density variations and anomalies both theoretically and empirically.
Trace anomaly on a quantum spacetime manifold
Spallucci, Euro; Smailagic, Anais; Nicolini, Piero
2006-04-15
In this paper we investigate the trace anomaly in a space-time where single events are delocalized as a consequence of short distance quantum coordinate fluctuations. We obtain a modified form of heat kernel asymptotic expansion which does not suffer from short distance divergences. Calculation of the trace anomaly is performed using an IR regulator in order to circumvent the absence of UV infinities. The explicit form of the trace anomaly is presented and the corresponding 2D Polyakov effective action and energy-momentum tensor are obtained. The vacuum expectation value of the energy-momentum tensor in the Boulware, Hartle-Hawking and Unruh vacua is explicitly calculated in a rt section of a recently found, noncommutative inspired, Schwarzschild-like solution of the Einstein equations. The standard short distance divergences in the vacuum expectation values are regularized in agreement with the absence of UV infinities removed by quantum coordinate fluctuations.
Understanding water's anomalies with locally favored structures
Russo, John
2013-01-01
Water is a complex structured liquid of hydrogen-bonded molecules that displays a surprising array of unusual properties, also known as water anomalies, the most famous being the density maximum at about $4^\\circ$C. The origin of these anomalies is still a matter of debate, and so far a quantitative description of water's phase behavior starting from the molecular arrangements is still missing. Here we provide a simple physical description from microscopic data obtained through computer simulations. We introduce a novel structural order parameter, which quantifies the degree of translational order of the second shell, and show that this parameter alone, which measures the amount of locally favored structures, accurately characterizes the state of water. A two-state modeling of these microscopic structures is used to describe the behavior of liquid water over a wide region of the phase diagram, correctly identifying the density and compressibility anomalies, and being compatible with the existence of a second ...
Radioactive anomaly discrimination from spectral ratios
Maniscalco, James; Sjoden, Glenn; Chapman, Mac Clements
2013-08-20
A method for discriminating a radioactive anomaly from naturally occurring radioactive materials includes detecting a first number of gamma photons having energies in a first range of energy values within a predetermined period of time and detecting a second number of gamma photons having energies in a second range of energy values within the predetermined period of time. The method further includes determining, in a controller, a ratio of the first number of gamma photons having energies in the first range and the second number of gamma photons having energies in the second range, and determining that a radioactive anomaly is present when the ratio exceeds a threshold value.
Spin and orbital moments of nanoscale Fe{sub 3}O{sub 4} epitaxial thin film on MgO/GaAs(100)
Liu, W. Q.; Xu, Y. B. E-mail: rzhang@nju.edu.cn; Wong, P. K. J.; Maltby, N. J.; Li, S. P.; Wang, X. F.; Zhang, R. E-mail: rzhang@nju.edu.cn; Du, J.; You, B.; Wu, J.; Bencok, P.
2014-04-07
Nanoscale Fe{sub 3}O{sub 4} epitaxial thin film has been synthesized on MgO/GaAs(100) spintronic heterostructure, and studied with X-ray magnetic circular dichroism. We have observed a total magnetic moment (m{sub l+s}) of (3.32?±?0.1)?{sub B}/f.u., retaining 83% of the bulk value. Unquenched orbital moment (m{sub l}) of (0.47?±?0.05)?{sub B}/f.u. has been confirmed by carefully applying the sum rule. The results offer direct experimental evidence of the bulk-like total magnetic moment and a large orbital moment in the nanoscale fully epitaxial Fe{sub 3}O{sub 4}/MgO/GaAs(100) heterostructure, which is significant for spintronics applications.
Neutron Electric Dipole Moment at Fixed Topology
Keh-Fei Liu
2009-07-03
We describe the finite volume effects of CP-odd quantities, such as the neutron electric dipole moment and the anapole moment in the $\\theta$-vacuum, under different topological sectors. We evaluate the three-point Green's functions for the electromagnetic current in a fixed non-trivial topological sector in order to extract these CP-odd observables. We discuss the role of zero modes in the CP-odd Green's function and show that, in the quenched approximation, there is a power divergence in the quark mass for CP-odd quantities at finite volume.
Pereira, Antonio Do Nascimento
2013-04-05
FAULT MAPPING USING THE MAGNETIC METHOD AT HICKORY SANDSTONE AQUIFER, LLANO UPLIFT, TEXAS A Thesis by ANT ONIO DO NASCIMENTO PEREIRA Submitted to the O ce of Graduate Studies of Texas A&M University in partial ful llment of the requirements... Magnetic eld or, Magnetic induction or, Magnetic eld density or, Magnetic ux density E Electric eld intensity H Magnetic eld intensity J Magnetizing eld, 0 Permeability of free space M Magnetic moment U Scalar potential v TABLE OF CONTENTS...
Chiral anomaly of antisymmetric tensor fields
Reuter, M.
1988-03-15
For antisymmetric tensor gauge fields of rank 2n-1 coupled to gravity in 4n dimensions it is shown that the symmetry under duality rotations is broken by quantum effects. The anomaly is related to a local version of the signature index theorem. The zeta-function technique, Fujikawa's method, and the stochastic regularization scheme are discussed.
A "Poisoning" Attack Against Online Anomaly Detection
Freytag, Johann-Christoph
A "Poisoning" Attack Against Online Anomaly Detection Marius Kloft Department of Computer Science it is robust against targeted "poisoning" attacks. The latter have been first investigated by Nelson et al. [1 of all data points observed so far. The key idea of a poisoning attack is to insert specially crafted
AUTOMATIC MIXED PIXEL CLASSIFICATIO (AMPC): ANOMALY CLASSIFICATION
Chang, Chein-I
14 AUTOMATIC MIXED PIXEL CLASSIFICATIO (AMPC): ANOMALY CLASSIFICATION In Chapter 13, one type of AMPC, automatic target detection and classification (ATDC) is investigated, which does not require any, an automatic thresholding method and four target discrimination measures are introduced in this chapter
Investigation into the semimagic nature of the tin isotopes through electromagnetic moments
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Allmond, J. M.; Stuchbery, A. E.; Galindo-Uribarri, A.; Padilla-Rodal, E.; Radford, D. C.; Batchelder, J. C.; Bingham, C. R.; Howard, M. E.; Liang, J. F.; Manning, B.; et al
2015-10-19
A complete set of electromagnetic moments, B(E2;0+1 2+1), Q(2+1), and g(2+1), have been measured from Coulomb excitation of semi-magic 112,114,116,118,120,122,124Sn (Z = 50) on natural carbon and titanium targets. The magnitude of the B(E2) values, measured to a precision of ~4%, disagree with a recent lifetime study [Phys. Lett. B 695, 110 (2011)] that employed the Doppler- shift attenuation method. The B(E2) values show an overall enhancement compared with recent theoretical calculations and a clear asymmetry about midshell, contrary to naive expectations. A new static electric quadrupole moment, Q(2+1), has been measured for 114Sn. The static quadrupole moments are generallymore »consistent with zero but reveal an enhancement near midshell; this had not been previously observed. The magnetic dipole moments are consistent with previous measurements and show a near monotonic decrease in value with neutron number. The current theory calculations fail to reproduce the electromagnetic moments of the tin isotopes. The role of 2p-2h and 4p-4h intruders, which are lowest in energy at mid shell and outside of current model spaces, needs to be investigated in the future.« less
Electrically driven nuclear spin resonance in a single-molecule magnet
Vallette, Bruno
Electrically driven nuclear spin resonance in a single-molecule magnet Institut NÃ©el : Nanospin Institut NÃ©el, CNRS-UJF, Grenoble NanoSpin #12;Â· Molecular magnets are characterised by : a magnetic moment a strong uniaxial anisotropy Mn12 Molecular magnets Fe8 #12;Â· Molecular magnets are characterised
Hg Anomalies In Soils- A Geochemical Exploration Method For Geothermal...
Hg Anomalies In Soils- A Geochemical Exploration Method For Geothermal Areas Jump to: navigation, search OpenEI Reference LibraryAdd to library Journal Article: Hg Anomalies In...
Chiral anomaly in the Schwinger-Symanzik formalism
Dittrich, W.; Reuter, M.
1985-03-15
It is shown how chiral anomalies appear nonperturbatively in the Schwinger-Symanzik functional formalism of quantum field theory.
Task and Machine Heterogeneities: Higher Moments Matter
Maciejewski, Anthony A. "Tony"
Task and Machine Heterogeneities: Higher Moments Matter Abdulla M. Al-Qawasmeh 1 , Anthony A.potter}@colostate.edu jtsmith@digitalglobe.com Abstract - One type of heterogeneous computing (HC) systems consists of machines in this matrix represents the ETC of a specific task on a specific machine when executed exclusively. Heuristics
Inversion of Moment Tensors in Anisotropic Media
Cerveny, Vlastislav
-Bohemia, Long Valley volcanic areas! Volumetric components are often interpreted as tensile faulting media may comprise apparent (non-real) volumetric components. Anisotropy effects wave amplitudes and anisotropy in the source area, formulas Outline #12;Theory Seismic Moment Tensor n s A isotropic materials
Neutron Electric Dipole Moment Matt Eichenfield
Golwala, Sunil
Neutron Electric Dipole Moment (NEDM) Matt Eichenfield 04/20/2007 #12;P and T Violations EDM to explain the Baryonic asymmetry of the universe #12;The Neutron's Constituents Three quarks Two down (q d neutron radius, the separation causing the SM NEDM
A. T. Tasci; A. Senol; C. Verep
2014-04-10
In this study we examine both anomalous magnetic and dipole moment type couplings of a heavy quark via its single production with subsequent dominant Standard Model decay modes at the Compact Linear Collider (CLIC). The signal and background cross sections are analyzed for heavy quark masses 600 and 700 GeV. We make the analysis to delimitate these couplings as well as to find the attainable integrated luminosities or 3$\\sigma$ observation limit.
ANTIDOTE: Understanding and Defending against Poisoning of Anomaly Detectors
Rubinstein, Benjamin
ANTIDOTE: Understanding and Defending against Poisoning of Anomaly Detectors Benjamin I. P poisoning techniques and develop a defense, in the context of a particular anomaly detector--namely the PCA-subspace method for detecting anomalies in backbone networks. For three poisoning schemes, we show how at- tackers
On the statistical modeling of persistence in total ozone anomalies
Wirosoetisno, Djoko
On the statistical modeling of persistence in total ozone anomalies Article Published Version in total ozone anomalies. Journal of Geophysical Research, 115. D16306. ISSN 0148-0227 doi: 10.1029/2009JD the statistical modeling of persistence in total ozone anomalies D. I. Vyushin,1 T. G. Shepherd,1 and V. E
Salary Anomalies pursuant to Article 15 of the Collective Agreement
Calgary, University of
Salary Anomalies pursuant to Article 15 of the Collective Agreement Dates Description Article ~ Human Resources will distribute the Salary Anomalies Advisory Committee Guidelines to the Deans. 15 online at: http://www.ucalgary.ca/hr/salary-anomalies 15.6 by January 30, 2015 ~ Deans will identify
Proximity-induced magnetism in transition-metal substituted graphene
Crook, Charles B.; Constantin, Costel; Ahmed, Towfiq; Zhu, Jian -Xin; Balatsky, Alexander V.; Haraldsen, Jason T.
2015-08-03
We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene systems with varying spatial separation. These calculations are compared for three different magnetic impurities, manganese, chromium, and vanadium. We determine the electronic band structure, density of states, and Millikan populations (magnetic moment) for each atom, as well as calculate the exchange parameter between the two magnetic atoms as a function of spatial separation. We find that the presence of magnetic impurities establishes a distinct magnetic moment in the graphene lattice, where the interactions are highly dependent on the spatial and magnetic characteristic between the magnetic and carbon atoms, which leads to either ferromagnetic or antiferromagnetic behavior. Furthermore, through an analysis of the calculated exchange energies and partial density of states, it is determined that interactions between the magnetic atoms can be classified as an RKKY interaction.
Proximity-induced magnetism in transition-metal substituted graphene
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Crook, Charles B.; Constantin, Costel; Ahmed, Towfiq; Zhu, Jian -Xin; Balatsky, Alexander V.; Haraldsen, Jason T.
2015-08-03
We investigate the interactions between two identical magnetic impurities substituted into a graphene superlattice. Using a first-principles approach, we calculate the electronic and magnetic properties for transition-metal substituted graphene systems with varying spatial separation. These calculations are compared for three different magnetic impurities, manganese, chromium, and vanadium. We determine the electronic band structure, density of states, and Millikan populations (magnetic moment) for each atom, as well as calculate the exchange parameter between the two magnetic atoms as a function of spatial separation. We find that the presence of magnetic impurities establishes a distinct magnetic moment in the graphene lattice, wheremore »the interactions are highly dependent on the spatial and magnetic characteristic between the magnetic and carbon atoms, which leads to either ferromagnetic or antiferromagnetic behavior. Furthermore, through an analysis of the calculated exchange energies and partial density of states, it is determined that interactions between the magnetic atoms can be classified as an RKKY interaction.« less
Remark on the Consistent Gauge Anomaly in Supersymmetric Theories
Ohshima, Y; Suzuki, H; Yasuta, H; Ohshima, Yoshihisa; Okuyama, Kiyoshi; Suzuki, Hiroshi; Yasuta, Hirofumi
1999-01-01
We present a direct field theoretical calculation of the consistent gauge anomaly in the superfield formalism, on the basis of a definition of the effective action through the covariant gauge current. The scheme is conceptually and technically simple and the gauge covariance in intermediate steps reduces calculational labors considerably. The resultant superfield anomaly, being proportional to the anomaly $d^{abc}=\\tr T^a\\{T^b,T^c\\}$, is minimal even without supplementing any counterterms. Our anomaly coincides with the anomaly obtained by Marinkovi\\'c as the solution of the Wess-Zumino consistency condition.
System and method for anomaly detection
Scherrer, Chad
2010-06-15
A system and method for detecting one or more anomalies in a plurality of observations is provided. In one illustrative embodiment, the observations are real-time network observations collected from a stream of network traffic. The method includes performing a discrete decomposition of the observations, and introducing derived variables to increase storage and query efficiencies. A mathematical model, such as a conditional independence model, is then generated from the formatted data. The formatted data is also used to construct frequency tables which maintain an accurate count of specific variable occurrence as indicated by the model generation process. The formatted data is then applied to the mathematical model to generate scored data. The scored data is then analyzed to detect anomalies.
Chiral anomalies and zeta-function regularization
Reuter, M.
1985-03-15
The zeta-function method for regularizing determinants is used to calculate the chiral anomalies of several field-theory models. In SU(N) gauge theories without ..gamma../sub 5/ couplings, the results of perturbation theory are obtained in an unambiguous manner for the full gauge theory as well as for the corresponding external-field problem. If axial-vector couplings are present, different anomalies occur for the two cases. The result for the full gauge theory is again uniquely determined; for its nongauge analog, however, ambiguities can arise. The connection between the basic path integral and the operator used to construct the heat kernel is investigated and the significance of its Hermiticity and gauge covariance are analyzed. The implications of the Wess-Zumino conditions are considered.
Holographic Trace Anomaly and Local Renormalization Group
Rajagopal, Srivatsan; Zhu, Yechao
2015-01-01
The Hamilton-Jacobi method in holography has produced important results both at a renormalization group (RG) fixed point and away from it. In this paper we use the Hamilton-Jacobi method to compute the holographic trace anomaly for four- and six-dimensional boundary conformal field theories (CFTs), assuming higher-derivative gravity and interactions of scalar fields in the bulk. The scalar field contributions to the anomaly appear in CFTs with exactly marginal operators. Moving away from the fixed point, we show that the Hamilton-Jacobi formalism provides a deep connection between the holographic and the local RG. We derive the local RG equation holographically, and verify explicitly that it satisfies Weyl consistency conditions stemming from the commutativity of Weyl scalings. We also consider massive scalar fields in the bulk corresponding to boundary relevant operators, and comment on their effects to the local RG equation.
Holographic Trace Anomaly and Local Renormalization Group
Srivatsan Rajagopal; Andreas Stergiou; Yechao Zhu
2015-08-19
The Hamilton-Jacobi method in holography has produced important results both at a renormalization group (RG) fixed point and away from it. In this paper we use the Hamilton-Jacobi method to compute the holographic trace anomaly for four- and six-dimensional boundary conformal field theories (CFTs), assuming higher-derivative gravity and interactions of scalar fields in the bulk. The scalar field contributions to the anomaly appear in CFTs with exactly marginal operators. Moving away from the fixed point, we show that the Hamilton-Jacobi formalism provides a deep connection between the holographic and the local RG. We derive the local RG equation holographically, and verify explicitly that it satisfies Weyl consistency conditions stemming from the commutativity of Weyl scalings. We also consider massive scalar fields in the bulk corresponding to boundary relevant operators, and comment on their effects to the local RG equation.
Gravity tests and the Pioneer anomaly
Marc-Thierry Jaekel; Serge Reynaud
2005-11-04
Experimental tests of gravity performed in the solar system show a good agreement with general relativity. The latter is however challenged by the Pioneer anomaly which might be pointing at some modification of gravity law at ranges of the order of the size of the solar system. We introduce a metric extension of general relativity which, while preserving the equivalence principle, modifies the coupling between curvature and stress tensors and, therefore, the metric solution in the solar system. The ``post-Einsteinian extension'' replaces Newton gravitation constant by two running coupling constants, which depend on the scale and differ in the sectors of traceless and traced tensors, so that the metric solution is characterized by two gravitation potentials. The extended theory has the capability to preserve compatibility with gravity tests while accounting for the Pioneer anomaly. It can also be tested by new experiments or, maybe, by having a new look at data of already performed experiments.
An Anzatz about Gravity, Cosmology, and the Pioneer Anomaly
Murad, Paul [Morningstar Applied Physics Inc., LLC, Vienna, VA 22182 (Austria)
2010-01-28
The Pulsar 1913+16 binary system may represent a 'young' binary system where previously it is claimed that the dynamics are due to either a third body or a gravitational vortex. Usually a binary system's trajectory could reside in a single ellipse or circular orbit; the double ellipse implies that the 1913+16 system may be starting to degenerate into a single elliptical trajectory. This could be validated only after a considerably long time period. In a majority of binary star systems, the weights of both stars are claimed by analysis to be the same. It may be feasible that the trajectory of the primary spinning star could demonstrate repulsive gravitational effects where the neutron star's high spin rate induces a repulsive gravitational source term that compensates for inertia. If true, then it provides evidence that angular momentum may be translated into linear momentum as a repulsive source that has propulsion implications. This also suggests mass differences may dictate the neutron star's spin rate as an artifact of a natural gravitational process. Moreover, the reduced matter required by the 'dark' mass hypothesis may not exist but these effects could be due to repulsive gravity residing in rotating celestial bodies.The Pioneer anomaly observed on five different deep-space spacecraft, is the appearance of a constant gravitational force directed toward the sun. Pioneer spacecraft data reveals that a vortex-like magnetic field exists emanating from the sun. The spiral arms of the Sun's magnetic vortex field may be causal to this constant acceleration. This may profoundly provide a possible experimental verification on a cosmic scale of Gertsenshtein's principle relating gravity to electromagnetism. Furthermore, the anomalous acceleration may disappear once the spacecraft passes out into a magnetic spiral furrow, which is something that needs to be observed in the future. Other effects offer an explanation from space-time geometry to the Yarkovsky thermal effects are discussed.
Large-Angle Anomalies in the CMB
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Copi, Craig J.; Huterer, Dragan; Schwarz, Dominik J.; Starkman, Glenn D.
2010-01-01
We review the recently found large-scale anomalies in the maps of temperature anisotropies in the cosmic microwave background. These include alignments of the largest modes of CMB anisotropy with each other and with geometry and direction of motion of the solar ssystem, and the unusually low power at these largest scales. We discuss these findings in relation to expectation from standard inflationary cosmology, their statistical significance, the tools to study them, and the various attempts to explain them.
Trace anomaly of the conformal gauge field
Sladkowski, J
1993-01-01
The proposed by Bastianelli and van Nieuwenhuizen new method of calculations of trace anomalies is applied in the conformal gauge field case. The result is then reproduced by the heat equation method. An error in previous calculation is corrected. It is pointed out that the introducing gauge symmetries into a given system by a field-enlarging transformation can result in unexpected quantum effects even for trivial configurations.
Cancellation of orbital and spin magnetism in UFe/sub 2/
Wulff, M.; Lander, G.H.; Lebech, B.; Delapalme, A.
1989-03-01
Polarized-neutron measurements have shown that the orbital and spin magnetic moments, which individually have a value of approx.0.23..mu../sub B/, almost completely cancel on the U sublattice in the ordered Laves phase UFe/sub 2/. This confirms a recent theoretical predicton and raises the possibility of ''magnetic'' compounds with zero total moment.
Pulsed Nuclear Magnetic Resonance: Spin Echoes MIT Department of Physics
Seager, Sara
Pulsed Nuclear Magnetic Resonance: Spin Echoes MIT Department of Physics (Dated: February 5, 2014) In this experiment, the phenomenon of Nuclear Magnetic Resonance (NMR) is used to determine the magnetic moments-factor in atomic spectroscopy and is given by g = (µ/µN )/I, (2) and µN is the nuclear magneton, e /2mp
The MOMENT to search for CP violation
Blennow, Mattias; Fernández-Martinez, Enrique
2015-01-01
In this letter, we analyze for the first time the physics reach in terms of sensitivity to leptonic CP violation of the proposed MuOn-decay MEdium baseline NeuTrino beam (MOMENT) experiment, a novel neutrino oscillation facility that would operate with neutrinos from muon decay. Apart from obtaining a sufficiently intense flux, the bottlenecks to the physics reach of this experiment will be achieving a high enough suppression of the atmospheric background and, particularly, attaining a sufficient level of charge identification. We thus present our results as a function of these two factors. As for the detector, we consider a very massive Gd-doped Water Cherenkov detector. We find that MOMENT will be competitive with other currently planned future oscillation experiments if a charge identification of at least 80 % can be achieved at the same time that the atmospheric background can be suppressed by at least a factor of ten. We also find a large synergy of MOMENT with the current generation of neutrino oscillat...
Perez Rojas, H.; Rodriguez Querts, E. [Instituto de Cibernetica, Matematica y Fisica, Calle E No. 309, esq. a 15 Vedado, C. Havana (Cuba)
2006-06-19
We study vacuum properties in a strong magnetic field as the zero temperature and zero density limit of quantum statistics. For charged vector bosons (W bosons) the vacuum energy density diverges for B > B{sub c} = m{sub w}{sup 2}/e, leading to vacuum instability. A logarithmic divergence of vacuum magnetization is found for B = Bc, which suggests that if the magnetic field is large enough, it is self-consistently maintained, and this mechanism actually prevents B from reaching the critical value Bc. For virtual neutral vector bosons bearing an anomalous magnetic moment, the instability of the ground state for B > B{sub c}{sup '} = m{sub n}{sup 2}/q also leads to the vacuum energy density divergence for fields B > B{sub c}{sup '} and to the magnetization divergence for B B{sub c}{sup '}. The possibility of virtual electron-positron pairs bosonization in strong magnetic field and the applicability of the neutral bosons model to describe the virtual positronium behavior in a magnetic field are discussed. We conjecture that this could lead to vacuum self-magnetization in QED.
Kanai, Shun; Tsujikawa, Masahito; Shirai, Masafumi; Miura, Yoshio; Matsukura, Fumihiro Ohno, Hideo
2014-12-01
We study the spin and orbital magnetic moments in Ta/Co{sub 0.4}Fe{sub 0.4}B{sub 0.2}/MgO by x-ray magnetic circular dichroism measurements as well as first-principles calculations, in order to clarify the origin of the perpendicular magnetic anisotropy. Both experimental and theoretical results show that orbital magnetic moment of Fe is more anisotropic than that of Co with respect to the magnetization direction. The anisotropy is larger for thinner CoFeB, indicating that Fe atoms at the interface with MgO contribute more than Co to the observed perpendicular magnetic anisotropy.
Supersymmetric Casimir Energy and the Anomaly Polynomial
Bobev, Nikolay; Kim, Hee-Cheol
2015-01-01
We conjecture that for superconformal field theories in even dimensions, the supersymmetric Casimir energy on a space with topology $S^1\\times S^{D-1}$ is equal to an equivariant integral of the anomaly polynomial. The equivariant integration is defined with respect to the Cartan subalgebra of the global symmetry algebra that commutes with a given supercharge. We test our proposal extensively by computing the supersymmetric Casimir energy for large classes of superconformal field theories, with and without known Lagrangian descriptions, in two, four and six dimensions.
Gravitational anomalies: a recipe for Hawking radiation
Saurya Das; Sean P. Robinson; Elias C. Vagenas
2008-03-27
We explore the method of Robinson and Wilczek for deriving the Hawking temperature of a black hole. In this method, the Hawking radiation restores general covariance in an effective theory of near-horizon physics which otherwise exhibits a gravitational anomaly at the quantum level. The method has been shown to work for broad classes of black holes in arbitrary spacetime dimensions. These include static black holes, accreting or evaporating black holes, charged black holes, rotating black holes, and even black rings. In the case of charged and rotating black holes, the expected super-radiant current is also reproduced.
The Pioneer Anomaly and a Machian Universe
Marcelo Samuel Berman
2008-08-06
We discuss astronomical and astrophysical evidence, which we relate to the principle of zero-total energy of the Universe, that imply several relations among the mass M, the radius R and the angular momentum L of a "large" sphere representing a Machian Universe. By calculating the angular speed, we find a peculiar centripetal acceleration for the Universe. This is an ubiquituous property that relates one observer to any observable. It turns out that this is exactly the anomalous acceleration observed on the Pioneers spaceships. We have thus, shown that this anomaly is to be considered a property of the Machian Universe. We discuss several possible arguments against our proposal.
Magnetic States in Fe Nanoparticles Imaged by Off-axis Electron Holography Luise Theil Kuhn1*
Dunin-Borkowski, Rafal E.
a procedure that is described elsewhere [1]. In FIG. 1 (d), a magnetic vortex surrounds a flux tube that runs.e. their magnetic configurations may be vortex-like. The critical size for this transition from single domain to vortex behaviour is crucial for determining the net magnetic moments carried by magnetic nanoparticles, i
"Flavored" Electric Dipole Moments in Supersymmetric Theories
J. Hisano; M. Nagai; P. Paradisi
2008-09-30
The Standard Model (SM) predictions for the hadronic electric dipole moments (EDMs) are well far from the present experimental resolutions, thus, the EDMs represent very clean probes of New Physics (NP) effects. Especially, within an MSSM framework with flavor-changing (but not necessarily CP violating) soft terms, large and potentially visible effects to the EDMs are typically expected. In this Letter we point out that, beyond-leading-order (BLO) effects, so far neglected in the literature, dominate over the leading-order (LO) effects in large regions of the parameter space, hence, their inclusion in the evaluation of the hadronic EDMs is unavoidable.
Detection of Surface Temperature Anomalies in the Coso Geothermal...
topography, albedo, and thermal inertia. This approach has the potential to reduce data noise and to reveal thermal anomalies which are not distinguishable in the uncorrected...
3D Magnetotelluric Characterization Of The Geothermal Anomaly...
3D Magnetotelluric Characterization Of The Geothermal Anomaly In The Llucmajor Aquifer System (Majorca, Spain) Jump to: navigation, search OpenEI Reference LibraryAdd to library...
Bouguer gravity anomalies, depth to bedrock, and shallow temperature...
Bouguer gravity anomalies, depth to bedrock, and shallow temperature in the Humboldt House geothermal area, Pershing County, Nevada Jump to: navigation, search OpenEI Reference...
IN SEARCH FOR THERMAL ANOMALIES IN THE COSO GEOTHERMAL FIELD...
sensing and field data is intended to evaluate the performance of remote sensing as a cost-effective geothermal exploration tool. We reason that if reliable thermal anomalies...
Probing top-Z dipole moments at the LHC and ILC
Röntsch, Raoul
2015-01-01
We investigate the weak electric and magnetic dipole moments of top quark-Z boson interactions at the Large Hadron Collider (LHC) and the International Linear Collider (ILC). Their vanishingly small magnitude in the Standard Model makes these couplings ideal for probing New Physics interactions and for exploring the role of top quarks in electroweak symmetry breaking. In our analysis, we consider the production of two top quarks in association with a Z boson at the LHC, and top quark pairs mediated by neutral gauge bosons at the ILC. These processes yield direct sensitivity to top quark-Z boson interactions and complement indirect constraints from electroweak precision data. Our computation is accurate to next-to-leading order in QCD, we include the full decay chain of top quarks and the Z boson, and account for theoretical uncertainties in our constraints. We find that LHC experiments will soon be able to probe weak dipole moments for the first time.
ASTER Thermal Anomalies in western Colorado
Zehner, Richard E.
2013-01-01
Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Publication Date: 2012 Title: ASTER Thermal Anomalies Western Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science (CIRES), University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains the areas identified as areas of anomalous surface temperature from ASTER satellite imagery. The temperature is calculated using the Emissivity Normalization Algorithm that separate temperature from emissivity. Areas that had temperature greater than 2?, and areas with temperature equal to 1? to 2?, were considered ASTER modeled very warm and warm surface exposures (thermal anomalies), respectively Spatial Domain: Extent: Top: 4547052.446651 m Left: 158917.090117 m Right: 4101162.228281 m Bottom: 4101162.228281 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System ’1984 (WGS ’1984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file
Neutrino oscillations in matter and in twisting magnetic fields
Maxim Dvornikov
2007-11-30
We find the solution to the Dirac equation for a massive neutrino with a magnetic moment propagating in background matter and interacting with the twisting magnetic field. In frames of the relativistic quantum mechanics approach to the description of neutrino evolution we use the obtained solution to derive neutrino wave functions satisfying the given initial condition. We apply the results to the analysis of neutrino spin oscillations in matter under the influence of the twisting magnetic field. Then on the basis of the yielded results we describe spin-flavor oscillations of Dirac neutrinos that mix and have non-vanishing matrix of magnetic moments. We again formulate the initial condition problem, derive neutrinos wave functions and calculate the transition probabilities for different magnetic moments matrices. The consistency of the obtained results with the quantum mechanical treatment of spin-flavor oscillations is discussed. We also consider several applications to astrophysical and cosmological neutrinos.
TEMPORAL PATTERN DISCOVERY FOR ANOMALY DETECTION IN A SMART HOME
Cook, Diane J.
TEMPORAL PATTERN DISCOVERY FOR ANOMALY DETECTION IN A SMART HOME Vikramaditya Jakkula , Diane J, cook}@eecs.wsu.edu Keywords: Knowledge discovery, smart homes, anomaly detection, temporal relations and relations on smart home datasets [10]. This paper describes a method of discovering temporal relations
Freshwater Availability Anomalies and Outbreak of Internal War
Columbia University
Freshwater Availability Anomalies and Outbreak of Internal War: Results from a Global Spatial Time Organizers: Centre for the Study of Civil War, International Peace Research Institute, Oslo (PRIO) & Centre Freshwater Availability Anomalies and Outbreak of Internal War: Results from a Global Spatial Time Series
Parity-violating anomalies and the stationarity of stochastic averages
Reuter, M.
1988-01-15
Within the framework of stochastic quantization the parity-violating anomalies in odd space-time dimensions are derived from the asymptotic stationarity of the stochastic average of a certain fermion bilinear. Contrary to earlier attempts, this method yields the correct anomalies for both massive and massless fermions.
Electric dipole moments of superheavy elements
Radži?t?, Laima; Jönsson, Per; Biero?, Jacek
2015-01-01
The multiconfiguration Dirac-Hartree-Fock (MCDHF) method was employed to calculate atomic electric dipole moments (EDM) of the superheavy element copernicium (Cn, $Z=112$). The EDM enhancement factors of Cn, here calculated for the first time, are about one order of magnitude larger than those of Hg. The exponential dependence of enhancement factors on atomic number $Z$ along group 12 of the periodic table was derived from the EDMs of the entire homolog series, $^{69}_{30}$Zn, $^{111}_{\\phantom{1}48}$Cd, $^{199}_{\\phantom{1}80}$Hg, $^{285}_{112}$Cn, and $^{482}_{162}$Uhb. These results show that superheavy elements with sufficiently large half-lives are good candidates for EDM searches.
Chameleon effect and the Pioneer anomaly
John D. Anderson; J. R. Morris
2012-04-12
The possibility that the apparent anomalous acceleration of the Pioneer 10 and 11 spacecraft may be due, at least in part, to a chameleon field effect is examined. A small spacecraft, with no thin shell, can have a more pronounced anomalous acceleration than a large compact body, such as a planet, having a thin shell. The chameleon effect seems to present a natural way to explain the differences seen in deviations from pure Newtonian gravity for a spacecraft and for a planet, and appears to be compatible with the basic features of the Pioneer anomaly, including the appearance of a jerk term. However, estimates of the size of the chameleon effect indicate that its contribution to the anomalous acceleration is negligible. We conclude that any inverse-square component in the anomalous acceleration is more likely caused by an unmodelled reaction force from solar-radiation pressure, rather than a chameleon field effect.
Magnetic properties of Er1?xDyxAl2 (0 ? x ? 1) compounds in low applied fields
Nirmala, R.; Paudyal, Durga; Pecharsky, V.K.; Gschneidner, Jr., K.A.
2010-04-21
Low field magnetic properties of the Laves phase RAl{sub 2} compounds (where R is a mixture of Er and Dy, i.e., Er{sub 1-x}Dy{sub x} and x = 0, 0.1, 0.14, 0.18, 0.25, 0.33, 0.5, and 1) have been studied. These compounds order ferromagnetically, and the middle members show both metastability in a narrow temperature window within the ferromagnetically ordered state and signatures of first order transitions in low applied fields. Results of first principles electronic structure calculations on Er{sub 0.75}Dy{sub 0.25}Al{sub 2} indicate a significant difference in the spin polarization in the 5d states of Er{sup 3+} and Dy{sup 3+} moments. In addition, anisotropic exchange and crystalline electric field effects arise from the random distribution of rare earth ions in the lattice. These and quadrupolar effects triggered by aspherical charge distributions of Er{sup 3+} and Dy{sup 3+} ions may compete and lead to the low temperature anomalies observed in low field magnetization data.
Scalar potential model of the Pioneer Anomaly
John C. Hodge
2007-01-20
The unexplained sunward acceleration $a_\\mathrm{P}$ of the Pioneer 10 (P10) and the Pioneer 11 (P11) spacecraft remains a mystery. A scalar potential model (SPM) that derived from considerations of galaxy clusters, of redshift, and of H{\\scriptsize{I}} rotation curves of spiral galaxies is applied to the Pioneer Anomaly. Matter is posited to warp the scalar potential $\\rho$ field. The changing $\\rho$ field along the light path causes the Pioneer Anomaly. The SPM is consistent with the general value of $a_\\mathrm{P}$; with the annual periodicity; with the differing $a_\\mathrm{P}$ between the spacecraft; with the discrepancy between {\\textit{Sigma}} and CHASMP programs at P10 (I) and their closer agreement at P10 (III); with the slowly declining $a_\\mathrm{P}$; with the low value of $a_\\mathrm{P}$ immediately before the P11's Saturn encounter; with the high uncertainty in the value of $a_\\mathrm{P}$ obtained during and after the P11's Saturn encounter; and with the cosmological connection suggested by $a_\\mathrm{P} \\approx cH_\\mathrm{o}$. The effect of the $\\rho$ field warp appears as the curvature of space proposed by general relativity (GR). The Hubble Law and $a_\\mathrm{P} \\approx cH_\\mathrm{o}$ are manifestations of the Newtonian spherical property. Therefore, gravitational attraction, the equivalence principle, and the planet ephemeris remain as described by GR. GR corresponds to the SPM in the limit in which the Sources and Sinks may be replaced by a flat and static $\\rho$ field such as between cluster cells and on the Solar System scale at a relatively large distance from a Source or Sink.
Neutron Electric Dipole Moments from Beyond the Standard Model...
Office of Scientific and Technical Information (OSTI)
Electric Dipole Moments from Beyond the Standard Model Physics Bhattacharya, Tanmoy Los Alamos National Laboratory Los Alamos National Laboratory; Cirigliano, Vincenzo Los...
Neutron Electric Dipole Moment and Tensor Charges from Lattice...
Office of Scientific and Technical Information (OSTI)
Neutron Electric Dipole Moment and Tensor Charges from Lattice QCD Citation Details In-Document Search This content will become publicly available on November 16, 2016 Title:...
CFD Combustion Modeling with Conditional Moment Closure using Tabulated Chemistry
Broader source: Energy.gov [DOE]
A method is presented that allows for efficient conditional moment closure combustion simulations through the use of a progress variable based parameterization of the combustion chemistry.
An Improved Experimental Limit on the Electric Dipole Moment of the Neutron
C. A. Baker; D. D. Doyle; P. Geltenbort; K. Green; M. G. D. van der Grinten; P. G. Harris; P. Iaydjiev; S. N. Ivanov; D. J. R. May; J. M. Pendlebury; J. D. Richardson; D. Shiers; K. F. Smith
2006-09-28
An experimental search for an electric-dipole moment (EDM) of the neutron has been carried out at the Institut Laue-Langevin (ILL), Grenoble. Spurious signals from magnetic-field fluctuations were reduced to insignificance by the use of a cohabiting atomic-mercury magnetometer. Systematic uncertainties, including geometric-phase-induced false EDMs, have been carefully studied. Two independent approaches to the analysis have been adopted. The overall results may be interpreted as an upper limit on the absolute value of the neutron EDM of |d_n| < 2.9 x 10^{-26} e cm (90% CL).
Local spin torque induced by electron electric dipole moment in the YbF molecule
Fukuda, Masahiro; Senami, Masato; Ogiso, Yoji; Tachibana, Akitomo
2014-10-06
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.
Radenski, Atanas
Page 1: Atanas Radenski: Anomaly-Free Component Adaptation with Class Overriding Anomaly-Free Component Adaptation with Class Overriding Atanas Radenski Chapman University Department of Computer Science://www.chapman.edu/~radenski/ Abstract Software components can be implemented and distributed as collections of classes, then adapted
The optimal fourth moment theorem Ivan Nourdin and Giovanni Peccati
Paris-Sud XI, Université de
The optimal fourth moment theorem Ivan Nourdin and Giovanni Peccati May 7, 2013 Abstract We compute the exact rates of convergence in total variation associated with the `fourth moment theorem' by Nualart a central limit theorem (CLT) if and only if the sequence of the corresponding fourth cumulants converges
GloptiPoly 3: moments, optimization and semidefinite programming
Henrion, Didier
be downloaded at www.laas.fr/henrion/software/gloptipoly3 The package, available as a compressed archive this package should be properly installed. Other semidefinite solvers can also be used provided) ... Generate moment SDP problem >> P Moment SDP problem Measure label = 1 Relaxation order = 3 Decision
Self-excited vibrations in turning: cutting moment analysis
Olivier Cahuc; Jean-Yves K'Nevez; Alain Gérard; Philippe Darnis; Gaëtan Albert; Claudiu F. Bisu; Céline Gérard
2010-07-06
This work aims at analysing the moment effects at the tool tip point and at the central axis, in the framework of a turning process. A testing device in turning, including a six-component dynamometer, is used to measure the complete torsor of the cutting actions in the case of self-excited vibrations. Many results are obtained regarding the mechanical actions torsor. A confrontation of the moment components at the tool tip and at the central axis is carried out. It clearly appears that analysing moments at the central axis avoids the disturbances induced by the transport of the moment of the mechanical actions resultant at the tool tip point. For instance, the order relation between the components of the forces is single. Furthermore, the order relation between the moments components expressed at the tool tip point is also single and the same one. But at the central axis, two different order relations regarding moments are conceivable. A modification in the rolling moment localization in the (y, z) tool plan is associated to these two order relations. Thus, the moments components at the central axis are particularly sensitive at the disturbances of machining, here the self-excited vibrations.
Remotely Sensed Thermal Anomalies in western Colorado
Hussein, Khalid
2012-02-01
Citation Information: Originator: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Publication Date: 2012 Title: Landsat Thermal Anomalies Western Edition: First Publication Information: Publication Place: Earth Science & Observation Center, Cooperative Institute for Research in Environmental Science (CIRES), University of Colorado, Boulder Publisher: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Description: This layer contains the areas identified as areas of anomalous surface temperature from Landsat satellite imagery in Western Colorado. Data was obtained for two different dates. The digital numbers of each Landsat scene were converted to radiance and the temperature was calculated in degrees Kelvin and then converted to degrees Celsius for each land cover type using the emissivity of that cover type. And this process was repeated for each of the land cover types (open water, barren, deciduous forest and evergreen forest, mixed forest, shrub/scrub, grassland/herbaceous, pasture hay, and cultivated crops). The temperature of each pixel within each scene was calculated using the thermal band. In order to calculate the temperature an average emissivity value was used for each land cover type within each scene. The NLCD 2001 land cover classification raster data of the zones that cover Colorado were downloaded from USGS site and used to identify the land cover types within each scene. Areas that had temperature residual greater than 2?, and areas with temperature equal to 1? to 2?, were considered Landsat modeled very warm and warm surface exposures (thermal anomalies), respectively Spatial Domain: Extent: Top: 4546381.234113 m Left: 140556.857021 m Right: 573390.000000 m Bottom: 4094583.641581 m Contact Information: Contact Organization: Earth Science &Observation Center (ESOC), CIRES, University of Colorado at Boulder Contact Person: Khalid Hussein Address: CIRES, Ekeley Building Earth Science & Observation Center (ESOC) 216 UCB City: Boulder State: CO Postal Code: 80309-0216 Country: USA Contact Telephone: 303-492-6782 Spatial Reference Information: Coordinate System: Universal Transverse Mercator (UTM) WGS’1984 Zone 13N False Easting: 500000.00000000 False Northing: 0.00000000 Central Meridian: -105.00000000 Scale Factor: 0.99960000 Latitude of Origin: 0.00000000 Linear Unit: Meter Datum: World Geodetic System ’1984 (WGS ’1984) Prime Meridian: Greenwich Angular Unit: Degree Digital Form: Format Name: Shape file
Optically induced magnetization in homogeneous, undoped dielectric media
Cafarella, Michael J.
frequencies is one half the electric dipole (ED) moment. As a consequence, magnetic dipole radiation generated dipole (ED). This is because only the electric field can generate linear charge acceleration and, and H2O at the fundamental input frequency. Excellent agreement is obtained with a classical magnetic
Third and fourth degree collisional moments for inelastic Maxwell models
V. Garzo; A. Santos
2007-11-29
The third and fourth degree collisional moments for $d$-dimensional inelastic Maxwell models are exactly evaluated in terms of the velocity moments, with explicit expressions for the associated eigenvalues and cross coefficients as functions of the coefficient of normal restitution. The results are applied to the analysis of the time evolution of the moments (scaled with the thermal speed) in the free cooling problem. It is observed that the characteristic relaxation time toward the homogeneous cooling state decreases as the anisotropy of the corresponding moment increases. In particular, in contrast to what happens in the one-dimensional case, all the anisotropic moments of degree equal to or less than four vanish in the homogeneous cooling state for $d\\geq 2$.
Nucleon tensor charges and electric dipole moments
Mario Pitschmann; Chien-Yeah Seng; Craig D. Roberts; Sebastian M. Schmidt
2014-12-22
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.
The search for permanent electric dipole moments
Kirch, Klaus
2013-02-13
Permanent electric dipole moments (EDMs) of fundamental systems with spin - particles, nuclei, atoms or molecules violate parity and time reversal invariance. Invoking the CPT theorem, time reversal violation implies CP violation. Although CP-violation is implemented in the standard electro-weak theory, EDM generated this way remain undetectably small. However, this CP-violation also appears to fail explaining the observed baryon asymmetry of our universe. Extensions of the standard theory usually include new sources of CP violation and often predict sizeable EDMs. EDM searches in different systems are complementary and various efforts worldwide are underway and no finite value has been established yet. The prototype of an EDM search is the pursuit of the EDM of the neutron. It has the longest history and at the same time is at the forefront of present research. The talk aims at giving an overview of the field with emphasis on our efforts within an international collaboration at PSI, nedm.web.psi.ch.
Lyapunov exponents at anomalies of SL(2,R)-actions
Hermann Schulz-Baldes
2006-07-12
Anomalies are known to appear in the perturbation theory for the one-dimensional Anderson model. A systematic approach to anomalies at critical points of products of random matrices is developed, classifying and analysing their possible types. The associated invariant measure is calculated formally. For an anomaly of so-called second degree, it is given by the groundstate of a certain Fokker-Planck equation on the unit circle. The Lyapunov exponent is calculated to lowest order in perturbation theory with rigorous control of the error terms.
Appraising nuclear octupole moment contributions to the hyperfine structures in $^{211}$Fr
Sahoo, B K
2015-01-01
Hyperfine structures of $^{211}$Fr due to the interactions of magnetic dipole ($\\mu$), electric quadrupole ($Q$) and magnetic octupole ($\\Omega$) moments with the electrons are investigated using the relativistic coupled-cluster (RCC) theory with an approximation of singles, doubles and important valence triples excitations in the perturbative approach. Validity of our calculations are substantiated by comparing the results with their available experimental values. Its $Q$ value has also been elevated by combining the measured hyperfine structure constant of the $7p \\ ^2P_{3/2}$ state with our improved calculation. Considering the preliminary value of $\\Omega$ from the nuclear shell-model, its contributions to the hyperfine structures up to the $7d \\ ^2D_{5/2}$ low-lying states in $^{211}$Fr are estimated. Energy splittings of the hyperfine transitions in many states have been assessed to find out suitability to carry out their precise measurements so that $\\Omega$ of $^{211}$Fr can be inferred from them unam...
Solar Eclipse Anomalies and Wave Refraction
Alasdair Macleod
2006-10-23
There is some inconclusive evidence that measurement devices sensitive to local gravitation exhibit anomalous behaviour during solar eclipses. We investigate if these findings can be incorporated into the standard general relativistic model of gravitation. The General Theory of Relativity (GTR) describes gravitation as the response of an object to local spacetime curvature. Gravitational waves travelling at the speed of light are then a necessary mechanism to maintain the required consistency between local curvature and distant gravitating mass. Gravitational waves will certainly be subject to refraction by bodies such as the moon and we explore if such an effect can result in an error in the apparent position of the sources and thereby give rise to the characteristic pattern of response associated with the eclipse anomaly. It is found there are phenomenological similarities, but only if gravitational waves are considered not merely to respond to spacetime curvature but are also significantly affected by the presence of mass, perhaps in a manner analogous to electromagnetic waves propagating through matter.
Eslami, L., E-mail: Leslami@iust.ac.ir; Faizabadi, E. [School of Physics, Iran University of Science and Technology, Tehran 16846 (Iran, Islamic Republic of)
2014-05-28
The effect of magnetic contacts on spin-dependent electron transport and spin-accumulation in a quantum ring, which is threaded by a magnetic flux, is studied. The quantum ring is made up of four quantum dots, where two of them possess magnetic structure and other ones are subjected to the Rashba spin-orbit coupling. The magnetic quantum dots, referred to as magnetic quantum contacts, are connected to two external leads. Two different configurations of magnetic moments of the quantum contacts are considered; the parallel and the anti-parallel ones. When the magnetic moments are parallel, the degeneracy between the transmission coefficients of spin-up and spin-down electrons is lifted and the system can be adjusted to operate as a spin-filter. In addition, the accumulation of spin-up and spin-down electrons in non-magnetic quantum dots are different in the case of parallel magnetic moments. When the intra-dot Coulomb interaction is taken into account, we find that the electron interactions participate in separation between the accumulations of electrons with different spin directions in non-magnetic quantum dots. Furthermore, the spin-accumulation in non-magnetic quantum dots can be tuned in the both parallel and anti-parallel magnetic moments by adjusting the Rashba spin-orbit strength and the magnetic flux. Thus, the quantum ring with magnetic quantum contacts could be utilized to create tunable local magnetic moments which can be used in designing optimized nanodevices.
Glotch, Timothy D.
magnetization46, and (3) electrostatic levitation and deposition of high-albedo, fine-grained, feldspar by magnetic field standoff of the solar wind Timothy D. Glotch1, Joshua L. Bandfield2, Paul G. Lucey3, Paul O magnetic fields. Thermal infrared data from this instrument display an anomaly in the position
Robust Multivariate Autoregression for Anomaly Detection in Dynamic Product Ratings
of the product "coconut-water" over time. Right: De- tected base behavior without anomalies. A real world example for a "coconut water" sold on Amazon (more details about the data are given in the experimental section
Anomaly Cancellation: A Retrospective From a Modern Perspective
John H. Schwarz
2001-07-09
The mechanism by which gauge and gravitational anomalies cancel in certain string theories is reviewed. The presentation is aimed at theorists who do not necessarily specialize in string theory.
Heterotic instantons and solitons in anomaly-free supergravity
I. Pesando; A. Tollsten
1991-10-29
We extend the classical heterotic instanton solutions to all orders in $\\alpha'$ using the equations of anomaly-free supergravity, and discuss the relation between these equations and the string theory $\\beta$-functions.
Fluid/Gravity Correspondence, Second Order Transport and Gravitational Anomaly
Eugenio Megias; Francisco Pena-Benitez
2013-07-29
We study the transport properties of a relativistic fluid affected by chiral and gauge-gravitational anomalies. The computation is performed in the framework of the fluid/gravity correspondence for a 5 dim holographic model with Chern-Simons terms in the action. We find new anomalous and non anomalous transport coefficients, as well as new contributions to the existing ones coming from the mixed gauge-gravitational anomaly. Consequences for the shear waves dispersion relation are analyzed.
Stress Tensors from Trace Anomalies in Conformal Field Theories
Christopher P. Herzog; Kuo-Wei Huang
2013-04-08
Using trace anomalies, we determine the vacuum stress tensors of arbitrary even dimensional conformal field theories in Weyl flat backgrounds. We demonstrate a simple relation between the Casimir energy on the real line times a sphere and the type A anomaly coefficient. This relation generalizes earlier results in two and four dimensions. These field theory results for the Casimir are shown to be consistent with holographic predictions in two, four, and six dimensions.
Seymour, P.
1986-01-01
This book deals with the cosmic magnetism in a non-mathematical way. It uses Faraday's very powerful and highly pictorial concept of lines of magnetic force and their associated physical properties to explain the structure and behavior of magnetic fields in extraterrestrial objects. Contents include: forces of nature; magnetic field of earth; solar and interplanetary magnetic fields; magnetic fields in the solar system; stars and pulsars; and magnetic fields of the milky way and other galaxies.
Pioneer Anomaly and the Kuiper Belt mass distribution
O. Bertolami; P. Vieira
2006-06-18
Pioneer 10 and 11 were the first probes sent to study the outer planets of the Solar System and Pioneer 10 was the first spacecraft to leave the Solar System. Besides their already epic journeys, Pioneer 10 and 11 spacecraft were subjected to an unaccounted effect interpreted as a constant acceleration toward the Sun, the so-called Pioneer anomaly. One of the possibilities put forward for explaining the Pioneer anomaly is the gravitational acceleration of the Kuiper Belt. In this work we examine this hypothesis for various models for the Kuiper Belt mass distribution. We find that the gravitational effect due to the Kuiper Belt cannot account for the Pioneer anomaly. Furthermore, we have also studied the hypothesis that drag forces can explain the the Pioneer anomaly; however we conclude that the density required for producing the Pioneer anomaly is many orders of magnitude greater than those of interplanetary and interstellar dust. Our conclusions suggest that only through a mission, the Pioneer anomaly can be confirmed and further investigated. If a mission with these aims is ever sent to space, it turns out, on account of our results, that it will be also a quite interesting probe to study the mass distribution of the Kuiper Belt.
Fourth moments reveal the negativity of the Wigner function
Adam Bednorz; Wolfgang Belzig
2011-05-31
The presence of unique quantum correlations is the core of quantum information processing and general quantum theory. We address the fundamental question of how quantum correlations of a generic quantum system can be probed using correlation functions defined for quasiprobability distributions. In particular we discuss the possibility of probing the negativity of a quasiprobability by comparing moments of the Wigner function. We show that one must take at least the fourth moments to find the negativity in general and the eighth moments for states with a rotationally invariant Wigner function.
Fourth moments reveal the negativity of the Wigner function
Bednorz, Adam [Faculty of Physics, University of Warsaw, Hoza 69, PL-00681 Warsaw (Poland); Belzig, Wolfgang [Fachbereich Physik, Universitaet Konstanz, D-78457 Konstanz (Germany)
2011-05-15
The presence of unique quantum correlations is the core of quantum-information processing and general quantum theory. We address the fundamental question of how quantum correlations of a generic quantum system can be probed using correlation functions defined for quasiprobability distributions. In particular, we discuss the possibility of probing the negativity of a quasiprobability by comparing moments of the Wigner function. We show that one must take at least the fourth moments to find the negativity in general and the eighth moments for states with a rotationally invariant Wigner function.
High-field magnetization processes in actinide intermetallics (invited)
Franse, J.J.M.; de Boer, F.R.; de Chatel, P.F.; Frings, P.H.; Menovsky, A.A. )
1991-04-15
In magnetically ordered intermetallics of uranium with {ital d} transition elements, the magnetic moment on the uranium site is often limited to values below 0.1{mu}{sub {ital B}}, with, in some cases, extremely large magnetic anisotropies. Several approaches are followed for explaining these small uranium moments: opposite directions and almost compensation of the spin and orbital moments, reduction of the uranium 5{ital f} moment by strong hybridization effects between the 5{ital f} and conduction electrons, and very weak itinerant magnetism of the 5{ital f} electrons. In the Laves-phase compounds UFe{sub 2} and UNi{sub 2}, the magnetic data have been explained in terms of opposite spin and orbital moments on the uranium sites. In the heavy-fermion compounds UPt{sub 3} and URu{sub 2}Si{sub 2}, on the contrary, a Kondo approach is followed, although coherence effects largely complicate a proper description. The experimental evidence for these different approaches will be reviewed.
Gravitational radiation from magnetically funneled supernova fallback onto a magnetar
Melatos, A.; Priymak, M., E-mail: amelatos@unimelb.edu.au, E-mail: m.priymak@pgrad.unimelb.edu.au [School of Physics, University of Melbourne, Parkville, VIC 3010 (Australia)
2014-10-20
Protomagnetars spun up to millisecond rotation periods by supernova fallback are predicted to radiate gravitational waves via hydrodynamic instabilities for ?10{sup 2} s before possibly collapsing to form a black hole. It is shown that magnetic funneling of the accretion flow (1) creates a magnetically confined polar mountain, which boosts the gravitational wave signal, and (2) 'buries' the magnetic dipole moment, delaying the propeller phase and assisting black hole formation.
Spin microscope based on optically detected magnetic resonance
Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)
2010-06-29
The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.
Spin microscope based on optically detected magnetic resonance
Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)
2009-11-10
The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of impaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.
Spin microscope based on optically detected magnetic resonance
Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)
2007-12-11
The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.
Spin microscope based on optically detected magnetic resonance
Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)
2009-10-27
The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.
Spin microscope based on optically detected magnetic resonance
Berman, Gennady P. (Los Alamos, NM); Chernobrod, Boris M. (Los Alamos, NM)
2010-07-13
The invention relates to scanning magnetic microscope which has a photoluminescent nanoprobe implanted in the tip apex of an atomic force microscope (AFM), a scanning tunneling microscope (STM) or a near-field scanning optical microscope (NSOM) and exhibits optically detected magnetic resonance (ODMR) in the vicinity of unpaired electron spins or nuclear magnetic moments in the sample material. The described spin microscope has demonstrated nanoscale lateral resolution and single spin sensitivity for the AFM and STM embodiments.
Electronic and magnetic properties of Fe and Mn doped two dimensional hexagonal germanium sheets
Soni, Himadri R. Jha, Prafulla K.
2014-04-24
Using first principles density functional theory calculations, the present paper reports systematic total energy calculations of the electronic properties such as density of states and magnetic moment of pristine and iron and manganese doped two dimensional hexagonal germanium sheets.
Optimal Panel Zone Participation in Steel Moment Frames
Ngo, Thanh Tat
2014-01-03
the overall seismic performance of that frame. As a result, the safety or reliability of a steel moment frame under earthquakes can be improved while maintaining the fabrication of the structure at an effective cost....
Dipole moment transitions in OH: theory (Dated: July 19, 2012)
= 0, e state is populated, where the e and f labels denote the so-called spectroscopic parity. We moments were calculated with the MOLPRO [1] program package at the internally contracted multireference
Tight Lower Bound for Linear Sketches of Moments
Andoni, Alexandr
2013-01-01
The problem of estimating frequency moments of a data stream has attracted a lot of attention since the onset of streaming algorithms [AMS99]. While the space complexity for approximately computing the p [superscript th] ...
Moments and Lyapunov exponents for the parabolic Anderson model
Borodin, Alexei
We study the parabolic Anderson model in (1+1) dimensions with nearest neighbor jumps and space–time white noise (discrete space/continuous time). We prove a contour integral formula for the second moment and compute the ...
U.S. Music Studies in a Moment of Danger
Tucker, Sherrie
2011-09-01
Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U.S. Music Studies in a "Moment of Danger" Tucker, Sherrie Journal of the American Musicological Society; Fall 2011; 64, 3; ProQuest Research...Reproduced with permission of the copyright owner. Further reproduction prohibited without permission. U.S. Music Studies in a "Moment of Danger" Tucker, Sherrie Journal of the American Musicological Society; Fall 2011; 64, 3; ProQuest Research...
Efficient solar anti-neutrino production in random magnetic fields
O. G. Miranda; T. I. Rashba; A. I. Rez; J. W. F. Valle
2004-05-12
We have shown that the electron anti-neutrino appearance in the framework of the spin flavor conversion mechanism is much more efficient in the case of neutrino propagation through random than regular magnetic field. This result leads to much stronger limits on the product of the neutrino transition magnetic moment and the solar magnetic field based on the recent KamLAND data. We argue that the existence of the random magnetic fields in the solar convective zone is a natural sequence of the convective zone magnetic field evolution.
Evaluation of permanent magnets for high temperature operations
Van Hees, Elizabeth
1985-01-01
as 3H F = x. m. H- &x where x = the magnetic susceptibility, which is the magnetic moment, M, divided by H, the field strength. The partial differential, 3H/ax, is the field gradient of the magnet, and m is the mass of the sample. This equation... is to inves- tigate the relevent magnetic properties of commercially availalbe magnetic materials for prolonged use in a high temperature environment (200'C to 450'C). Such materials can be utilized in geothermal and petroleum well logging. A device...
Simulating net particle production and chiral magnetic current in a CP-odd domain
Kenji Fukushima
2015-01-29
We elucidate the numerical formulation to simulate net production of particles and anomalous currents with CP-breaking background fields which cause an imbalance between particles and anti-particles. For a concrete demonstration we numerically impose pulsed electric and magnetic fields to observe that the dynamical chiral magnetic current follows together with the net particle production. The produced particle density is quantitatively consistent with the axial anomaly, while the chiral magnetic current shows a delay before the onset, which leads to a suppression effect, and then approaches what is expected from the axial anomaly.
Automatic Construction of Anomaly Detectors from Graphical Models
Ferragut, Erik M [ORNL; Darmon, David M [ORNL; Shue, Craig A [ORNL; Kelley, Stephen [ORNL
2011-01-01
Detection of rare or previously unseen attacks in cyber security presents a central challenge: how does one search for a sufficiently wide variety of types of anomalies and yet allow the process to scale to increasingly complex data? In particular, creating each anomaly detector manually and training each one separately presents untenable strains on both human and computer resources. In this paper we propose a systematic method for constructing a potentially very large number of complementary anomaly detectors from a single probabilistic model of the data. Only one model needs to be trained, but numerous detectors can then be implemented. This approach promises to scale better than manual methods to the complex heterogeneity of real-life data. As an example, we develop a Latent Dirichlet Allocation probability model of TCP connections entering Oak Ridge National Laboratory. We show that several detectors can be automatically constructed from the model and will provide anomaly detection at flow, sub-flow, and host (both server and client) levels. This demonstrates how the fundamental connection between anomaly detection and probabilistic modeling can be exploited to develop more robust operational solutions.
Detection of data taking anomalies for the ATLAS experiment
De Castro Vargas Fernandes, Julio; The ATLAS collaboration; Lehmann Miotto, Giovanna
2015-01-01
The physics signals produced by the ATLAS detector at the Large Hadron Collider (LHC) at CERN are acquired and selected by a distributed Trigger and Data AcQuistition (TDAQ) system, comprising a large number of hardware devices and software components. In this work, we focus on the problem of online detection of anomalies along the data taking period. Anomalies, in this context, are defined as an unexpected behaviour of the TDAQ system that result in a loss of data taking efficiency: the causes for those anomalies may come from the TDAQ itself or from external sources. While the TDAQ system operates, it publishes several useful information (trigger rates, dead times, memory usage…). Such information over time creates a set of time series that can be monitored in order to detect (and react to) problems (or anomalies). Here, we approach TDAQ operation monitoring through a data quality perspective, i.e, an anomaly is seen as a loss of quality (an outlier) and it is reported: this information can be used to rea...
Tsai, C. Y.; Chen, H. R.; Hsieh, W. F., E-mail: wfhsieh@mail.nctu.edu.tw [Department of Photonics and Institute of Electro-Optical Engineering, National Chiao Tung University, 1001 Ta Hsueh Rd., Hsinchu 300, Taiwan (China); Cheng, H. M.; Tsai, L. N. [Material and Chemical Research Laboratories, Industrial Technology Research Institute, Hsinchu 310, Taiwan (China); Huang, K. F.; Lai, C. H. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 31013, Taiwan (China); Chu, Y. H. [Department of Materials Science and Engineering, National Chiao Tung University, Hsinchu 31040, Taiwan (China)
2014-06-23
Temperature dependent magnetic and phonon anomalies in epitaxial self-assembled CoFe{sub 2}O{sub 4} (CFO) rods embedded in BaTiO{sub 3} (BTO) matrix nanostructures were investigated. The temperature dependence of A{sub 1}(2TO) phonon frequency of BTO indicates that the BTO matrix experiences structural transformations. The lattice strain produced during the structural transformations drives spin reorientation in CFO rods, resulting in anomalous changes of magnetization. Through correlating the phonon anomalies with the increase of in-plane spin ordering, we show the spin-phonon coupling induces the softening of A{sub 1g} and A{sub 1}(2TO) phonons. It suggests that spin strongly couples with lattice strain and phonons in this nanostructure.
Tracing Remnants of the Baryon Vector Current Anomaly in Neutron Radiative Beta Decay
Susan Gardner; Daheng He
2011-01-06
Harvey, Hill, and Hill have found that unexpected interactions involving the nucleon, photon, and weak gauge bosons at low energies emerge from gauging the axial anomaly of QCD under the full electroweak symmetry of the Standard Model (SM). In this contribution we consider how such interactions can be isolated through a triple-product momentum correlation in neutron radiative beta-decay. The correlation is both parity- and naively time-reversal-odd, so that it vanishes in the Standard Model save for effects induced by final-state interactions (FSI). Nevertheless, the correlation can be generated by sources of CP violation beyond the Standard Model, and such couplings, being spin-independent, are not constrained by the nonobservation of the neutron electric dipole moment (EDM). We consider the sorts of limits on its strength which can be determined at existing and anticipated facilities, as well as the size of induced correlations from known FSI. We also briefly consider the possibility of nuclear beta-decay studies as well as the prospects for muon-induced reaction studies.
Galanakis, I. [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France)] [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France); Ostanin, S. [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France)] [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France); Alouani, M. [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France)] [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France); Dreysse, H. [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France)] [Institut de Physique et de Chimie des Materiaux de Strasbourg (IPCMS), 23 rue du Loess, 67037 Strasbourg Cedex, (France); Wills, J. M. [Center for Materials Science and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)] [Center for Materials Science and Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87544 (United States)
2000-01-01
A detailed theoretical study of magnetic and structural properties of Fe{sub 0.5}Pd{sub 0.5} ordered face-centered tetragonal (fct) alloy, using both the local spin density approximation (LSDA) and the generalized gradient approximation (GGA), is presented. The total energy surface as a function of the lattice parameters a and c shows a long valley where stable structures may exist. Our calculation using the GGA predicts a magnetic phase transition from perpendicular to parallel magnetization as a function of the lattice parameter, whereas LSDA favors always the [001] magnetization axis for all values of the lattice parameters. The spin and orbital magnetic moments and x-ray magnetic circular dichroism spectra are calculated for the easy [001] and the hard [100] magnetization axis and for three sets of experimental lattice parameters, and are compared to the available experimental results on these films. A supercell calculation for a 4 monolayer Fe{sub 0.5}Pd{sub 0.5} thin film produced similar results. While the spin magnetic moments are in fair agreement with experiment, the orbital magnetic moments are considerably underestimated. To improve the agreement with experiment we included an atomic orbital polarization term; however, the computed orbital moments scarcely changed. (c) 2000 The American Physical Society.
UMn2Al20: Small Itinerant Moment or Induced Local Moment Ferromagnetism?
Lawrence, Jon
. Since the 5f electrons of uranium have the possibility of being in the 5f2 electron configuration remains as an important issue for uranium intermetallic compounds, and more detailed experiments on good a centrifuge. The magnetization was measured in a commercial superconducting quantum interference device (SQUID
Kohn, Gabriel (Omer, IL); Hicho, George (Derwood, MD); Swartzendruber, Lydon (New Carrollton, MD)
1997-01-01
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.
Kohn, G.; Hicho, G.; Swartzendruber, L.
1997-04-08
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.
X-ray magnetic circular dichroism at the U M{sub 4,5} absorption edges of UFe{sub 2}
Finazzi, M.; Sainctavit, P.; Dias, A.; Kappler, J.; Krill, G.; Sanchez, J.; Dalmas de Reotier, P.; Yaouanc, A.; Rogalev, A.; Goulon, J.
1997-02-01
We present an x-ray magnetic circular dichroism study performed at the U M{sub 4,5} edges on UFe{sub 2}, a ferromagnet with almost itinerant 5f electrons. The analysis of the branching ratio of the U M{sub 4,5} edges confirms the fact that the occupation number of the 5f states in UFe{sub 2} is lower than in other compounds where the f electrons are more localized. Magnetic circular dichroism effects are observed consistently with the presence of an orbital 5f magnetic moment which aligns parallel to the total magnetic moment. In agreement with a polarized neutron study, we find a nearly perfect cancellation of the U-5f spin and orbital magnetic moments, which results in a vanishing small total U-5f magnetic moment. Results are discussed in comparison with atomic multiplet calculations. {copyright} {ital 1997} {ital The American Physical Society}
Search for a Standard Explanation of the Pioneer Anomaly
John D. Anderson; Eunice L. Lau; Slava G. Turyshev; Philip A. Laing; Michael Martin Nieto
2002-06-12
The data from Pioneer 10 and 11 shows an anomalous, constant, Doppler frequency drift that can be interpreted as an acceleration directed towards the Sun of a_P = (8.74 \\pm 1.33) x 10^{-8} cm/s^2. Although one can consider a new physical origin for the anomaly, one first must investigate the contributions of the prime candidates, which are systematics generated on board. Here we expand upon previous analyses of thermal systematics. We demonstrate that thermal models put forth so far are not supported by the analyzed data. Possible ways to further investigate the nature of the anomaly are proposed.
Simpler algorithm for estimating frequency moments of data streams Lakshminath Bhuvanagiri
Ganguly, Sumit
Ganguly Deepanjan Kesh Chandan Saha§ Abstract The problem of estimating the kth frequency moment Fk over
Probing top-Z dipole moments at the LHC and ILC
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Röntsch, Raoul; Schulze, Markus
2015-08-01
We investigate the weak electric and magnetic dipole moments of top quark-Z boson interactions at the Large Hadron Collider (LHC) and the International Linear Collider (ILC). Their vanishingly small magnitude in the Standard Model makes these couplings ideal for probing New Physics interactions and for exploring the role of top quarks in electroweak symmetry breaking. In our analysis, we consider the production of two top quarks in association with a Z boson at the LHC, and top quark pairs mediated by neutral gauge bosons at the ILC. These processes yield direct sensitivity to top quark-Z boson interactions and complement indirectmore »constraints from electroweak precision data. Our computation is accurate to next-to-leading order in QCD, we include the full decay chain of top quarks and the Z boson, and account for theoretical uncertainties in our constraints. Furthermore, we find that LHC experiments will soon be able to probe weak dipole moments for the first time.« less
Laser spectroscopy investigation of the nuclear moments and radii of lutetium isotopes
Georg, U; Keim, M; Klein, A; Neugart, R; Neuroth, M; Schulz, C; Rao, P M; Lievens, P
1998-01-01
Collinear laser spectroscopy experiments in the LuI transition $5d6s\\!^{2} \\; ^{2}\\!D_{3/2} \\rightarrow 5d6s6p \\; ^{2}\\!D_{3/2}$ were performed on all lutetium isotopes in the range of $^{161-179}$Lu. The nuclear spins, magnetic moments and quadrupole moments were determined from the hyperfine structures observed for 19 ground states and 11 isomers. Variations in the mean square charge radii as a function of neutron number were obtained from the isotope shifts. These data considerably extend the systematics of the properties of nuclei in the upper rare-earth region. A particular feature is the appearance of high-spin and low-spin ground states and isomeric states in the vicinity of the stable $^{175}$Lu, partly arising from aligned neutron pairs. The present results clearly show that the deformation properties are nearly independent of the occupancy and the coupling of single-particle states. Theoretical predictions of deformation are confirmed in a consistent description of the measured radii and quadrupole ...
Magnets & Magnet Condensed Matter Science
McQuade, D. Tyler
Sights from around the Magnet Lab in 2010. On the cover MAGNETS & MAGNET MATERIALS Engineering materials in Mesoporous Silica SBA-15 31 YBCO Pancake Wound Test Coil for 32-T Magnet Development 32 Strong Vortex Pinning from Marine Cyanobacteria 37 Heavy Petroleum Composition 2. Progression of the Boduszynski Model
Moments of $?$ meson spectral functions in vacuum and nuclear matter
Philipp Gubler; Wolfram Weise
2015-07-14
Moments of the $\\phi$ meson spectral function in vacuum and in nuclear matter are analyzed, combining a model based on chiral SU(3) effective field theory (with kaonic degrees of freedom) and finite-energy QCD sum rules. For the vacuum we show that the spectral density is strongly constrained by a recent accurate measurement of the $e^+ e^- \\to K^+ K^-$ cross section. In nuclear matter the $\\phi$ spectrum is modified by interactions of the decay kaons with the surrounding nuclear medium, leading to a significant broadening and an asymmetric deformation of the $\\phi$ meson peak. We demonstrate that both in vacuum and nuclear matter, the first two moments of the spectral function are compatible with finite-energy QCD sum rules. A brief discussion of the next-higher spectral moment involving strange four-quark condensates is also presented.
Electric Dipole Moments of Charged Leptons with Sterile Fermions
Abada, Asmaa
2015-01-01
We address the impact of sterile fermions on charged lepton electric dipole moments. Any experimental signal of these observables calls for scenarios of physics beyond the Standard Model providing new sources of CP violation. In this work, we consider a minimal extension of the Standard Model via the addition of sterile fermions which mix with active neutrinos and we derive the corresponding analytical expressions for the electric dipole moments of charged leptons at two-loop order. Our study reveals that, in order to have a non-vanishing contribution in this framework, the minimal extension necessitates the addition of at least 2 sterile fermion states to the Standard Model field content. Our conclusion is that sterile neutrinos can give significant contributions to the charged lepton electric dipole moments, some of them lying within present and future experimental sensitivity if the masses of the non-degenerate sterile states are both above the electroweak scale. The Majorana nature of neutrinos is also im...
Third-frequency-moment sum rule for electronic multilayers
Lu, Dexin [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People's Republic of China (China)] [Department for Intensive Instruction, Nanjing University, Nanjing 210093, People's Republic of China (China); Golden, Kenneth I. [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States)] [Department of Mathematics and Statistics, Department of Physics, University of Vermont, Burlington, Vermont 05401-1455 (United States)
2000-01-01
The authors establish the third-frequency-moment sum rules for the density-density response matrix of electronic multilayer structures modeled as an array of N parallel two-dimensional (2D) electron-plasma monolayers. Layer densities and spacings between adjacent layers need not be equal. Contact is made with previously established sum rules for the isolated 2D electron liquid and type-1 infinite superlattices. The case of the equal-density bilayer is considered and its third frequency-moment-sum-rules for the in-phase and out-of-phase inverse dielectric functions are formulated. (c) 2000 The American Physical Society.
The moment problem and its relation to statistics
Wood, Sam Madeley
1958-01-01
and is sometimes denoted by x. The expected value of a function g(x) for a probability function f(x) would be E fv("1) = j a("~ f(") d , In connection with expected value we will establish the following properties: (a) E(ax) = aE(x) Proof: E(ax) = (ax) f..., . . . ) are identical, provided they exist, can be found in Cramer's text, ref (2), erne 1 al ethods o S a s. Theorem 2) If the rth absolute moment, r = 0, 1, 2, . . . of a dis- tribution function is finite, then the nth absolute moment where Oc n & r, and n = 0, 1...
Phase equilibria of polydisperse hydrocarbons: moment free energy method analysis
Alessandro Speranza; Francesca Di Patti; Alessandro Terenzi
2010-12-14
We analyze the phase equilibria of systems of polydisperse hydrocarbons by means of the recently introduced moment method. Hydrocarbons are modelled with the Soave-Redlick-Kwong and Peng-Robinson equations of states. Numerical results show no particular qualitative difference between the two equations of states. Furthermore, in general the moment method proves to be an excellent method for solving phase equilibria of polydisperse systems, showing excellent agreement with previous results and allowing a great improvement in generality of the numerical scheme and speed of computation.
Electric Power System Anomaly Detection Using Neural Networks
Tronci, Enrico
to hijacking of measures, changes in the power network topology (i.e. transmission lines breaking) and unexElectric Power System Anomaly Detection Using Neural Networks Marco Martinelli1 , Enrico Tronci1. The aim of this work is to propose an approach to monitor and protect Electric Power System by learning
Anomaly of Tensionless String in Light-cone Gauge
Kenta Murase
2015-03-04
The classical tensionless string theory has the spacetime conformal symmetry. We expect and require that the quantum tensionless string theory has it too. In the BRST quantization method, the theory has no spacetime conformal anomaly in two dimensions. On the other hand, in the light-cone gauge quantization without the mode expansion, the theory in $D>3$ has the spacetime conformal anomaly in the traceless part of $[\\mathcal{J}^{-I}, \\mathcal{K}^{J}]$ in some operator order. In this paper, we consider a tensionless closed bosonic string in the light-cone gauge and investigate the spacetime conformal anomaly in the theory with the mode expansion. The appearance of the spacetime conformal anomaly in the light-cone gauge is different between the case of $D>3$ and the case of $D=3$ and depends on the choice of the operator order. Therefore we must consider dangerous commutators in the spacetime conformal symmetry of $D>3$ and $D=3$ in each operator order separately. Specifically we calculate dangerous commutators, $[\\mathcal{J}^{-I},\\mathcal{K}^{K}]$ in $D>3$ and $\\tilde{\\mathcal{K}}^{-}\\equiv -i[\\mathcal{J}^{-}, \\tilde{\\mathcal{K}}^{-}]$ and $[\\mathcal{J}^{-}, \\tilde{\\mathcal{K}}^{-}]$ in $D=3$, in two types of the operator order.
Anomaly of Tensionless String in Light-cone Gauge
Murase, Kenta
2015-01-01
The classical tensionless string theory has the spacetime conformal symmetry. We expect and require that the quantum tensionless string theory has it too. In the BRST quantization method, the theory has no spacetime conformal anomaly in two dimensions. On the other hand, in the light-cone gauge quantization without the mode expansion, the theory in $D>3$ has the spacetime conformal anomaly in the traceless part of $[\\mathcal{J}^{-I}, \\mathcal{K}^{J}]$ in some operator order. In this paper, we consider a tensionless closed bosonic string in the light-cone gauge and investigate the spacetime conformal anomaly in the theory with the mode expansion. The appearance of the spacetime conformal anomaly in the light-cone gauge is different between the case of $D>3$ and the case of $D=3$ and depends on the choice of the operator order. Therefore we must consider dangerous commutators in the spacetime conformal symmetry of $D>3$ and $D=3$ in each operator order separately. Specifically we calculate dangerous commutators...
Freshwater Availability Anomalies and Outbreak of Internal War
Columbia University
Freshwater Availability Anomalies and Outbreak of Internal War: Results from a Global Spatial Time, Asker, near Oslo, 2123 June 2005 Organizers: Centre for the Study of Civil War, International Peace War: Results from a Global Spatial Time Series Analysis1 Abstract We investigated the relationship
Stealthy Poisoning Attacks on PCA-based Anomaly Detectors
Tygar, Doug
Stealthy Poisoning Attacks on PCA-based Anomaly Detectors Benjamin I. P. Rubinstein1 Blaine Nelson1 detection, we present and evaluate short-term and long-term data poison- ing schemes that trade-off between poisoning duration and the volume of traffic injected for poisoning. Stealthy Boil- ing Frog attacks
Multivariate SVD Analyses For Network Anomaly Detection Lingsong Zhang
Shen, Haipeng
Multivariate SVD Analyses For Network Anomaly Detection Lingsong Zhang Haipeng Shen Zhengyuan Zhu components analysis on multivariate data rather than univariate data. A multivariate approach allows us by the multivariate outliers, being more representative of anomalous behavior. We can define the signifi- cance
Anomaly-free representations of the holonomy-flux algebra
SangChul Yoon
2008-09-07
We work on the uniqueness, gr-qc/0504147, of representations of the holonomy-flux algebra in loop quantum gravity. We argue that for analytic diffeomorphisms, the flux operators can be only constants as functions on the configuration space in representations with no anomaly, which are zero in the standard representation.
Detecting Anomalies in Unmanned Vehicles Using the Mahalanobis Distance
Kaminka, Gal A.
the vehicles deviations from nominal behavior. I. INTRODUCTION Unmanned Aerial Vehicles (UAVs) and UnmannedDetecting Anomalies in Unmanned Vehicles Using the Mahalanobis Distance Raz Lin, Eliyahu Khalastchi 52900 {linraz,galk}@cs.biu.ac.il Abstract-- The use of unmanned autonomous vehicles is becoming more
The Pioneer Anomaly and a Rotating Gödel Universe
Thomas L. Wilson; Hans-Joachim Blome
2009-08-27
Based upon a simple cosmological model with no expansion, we find that the rotational terms appearing in the G/"odel universe are too small to explain the Pioneer anomaly. Although it contributes, universal rotation is not the cause of the Pioneer effect.
X-ray magnetic circular dichroism study of epitaxial magnetite ultrathin film on MgO(100)
Liu, W. Q.; Xu, Y. B. E-mail: rzhang@nju.edu.cn; Song, M. Y.; Lin, J. G.; Maltby, N. J.; Li, S. P.; Samant, M. G.; Parkin, S. S. P.; Bencok, P.; Steadman, Paul; Dobrynin, Alexey; Zhang, R. E-mail: rzhang@nju.edu.cn
2015-05-07
The spin and orbital magnetic moments of the Fe{sub 3}O{sub 4} epitaxial ultrathin film synthesized by plasma assisted simultaneous oxidization on MgO(100) have been studied with X-ray magnetic circular dichroism. The ultrathin film retains a rather large total magnetic moment, i.e., (2.73?±?0.15)??{sub B}/f.u., which is ?70% of that for the bulk-like Fe{sub 3}O{sub 4}. A significant unquenched orbital moment up to 0.54?±?0.05??{sub B}/f.u. was observed, which could come from the symmetry breaking at the Fe{sub 3}O{sub 4}/MgO interface. Such sizable orbital moment will add capacities to the Fe{sub 3}O{sub 4}-based spintronics devices in the magnetization reversal by the electric field.
are well above the noise level of magnetic gradient data. The contribution from higher order moments may is mainly driven by the digging of nonhazardous materials, with as much Manuscript received March 31, 2007
Diagenetic and Detrial Origin of Moretane Anomalies through the Permian-Triassic Boundary
French, Katherine L.
Many biogeochemical anomalies coincide with the Late Permian Extinction (LPE; 252.28 Ma). Several mechanisms have been proposed to explain the moretane/hopane anomaly that has been identified in samples from Meishan GSSP ...
Farrara, J. D.; Yu, J.-Y.
2002-01-01
the recent notable Midwest summer flood ( drought) events ofdrought in particular—the rain- fall anomalies in the Midwest
Magnetic structure of Gd[subscript 5]Ge[subscript 4
Tan, L.; Kreyssig, A.; Kim, J.W.; Goldman, A.I.; McQueeney, R.J.; Wermeille, D.; Sieve, B.; Lograsso, T.A.; Schlagel, D.L.; Budko, S.L.; Pecharsky, V.K.; Gschneidner, Jr., K.A. (Ames); (Iowa State)
2010-07-20
Gd{sub 5}Ge{sub 4} crystallizes in the orthorhombic space group Pnma, and orders antiferromagnetically below the Neel temperature T{sub N} {approx} 127 K. We have employed x-ray resonant magnetic scattering to elucidate the details of the magnetic structure. The magnetic unit cell is the same as the chemical unit cell. From azimuth scans and the Q dependence of the magnetic scattering, all three Gd sites in the structure were determined to be in the same magnetic space group Pnma. The magnetic moments are primarily aligned along the c axis and the c components of the magnetic moments at the three different sites are equal. The ferromagnetic Gd-rich slabs are stacked antiferromagnetically along the b direction.
The Effect of Connection Fractures on Steel Moment Resisting Frame
Sweetman, Bert
The Effect of Connection Fractures on Steel Moment Resisting Frame Seismic Demands and Safety - The Effect of Connection Fractures on SMRF Seismic Demands and Safety 1. Contents, Approach, Models........................................................................................C-1 "Numerical Example of the Proposed SAC Procedure for Assessing the Annual Exceedance Probabilities
Moment Based Dimension Reduction for Multivariate Response Regression
Bura, Efstathia
Moment Based Dimension Reduction for Multivariate Response Regression Xiangrong Yin Efstathia Bura January 20, 2005 Abstract Dimension reduction aims to reduce the complexity of a regression without re- quiring a pre-specified model. In the case of multivariate response regressions, covariance
Stability analysis of graphite crystal lattice with moment interactions
Krivtsov, Anton M.
of graphite lattice is considered. The model is based on usage of moment interactions. Carbon atom transversal stiffness to provide the stability of the hexagonal lattice. Proc. of XXXIV Summer School between atoms is r0. The angles between bonds and are shown on Fig.1. Let us present internal energy
Evaluating Centroid-Moment-Tensor Uncertainty in the New Version
Cerveny, Vlastislav
Sokos and Jirí Zahradník Online Material: Additional figures. INTRODUCTION Focal mechanism and moment are the FMNEAREG and KIWI software packages. Focal Mechanism from NEAr source to REGional distance records software (KInematic Waveform Inversion; Cesca et al., 2010) allows the automatic retrieval of point- source
A multivariate quadrature based moment method for supersonic combustion modeling
Raman, Venkat
QMOM is then used for studying an experimental Mach 2.2 supersonic cavity based combustor. Development of predictiveA multivariate quadrature based moment method for supersonic combustion modeling Pratik Donde models for supersonic combustion is a critical step in design and development of scramjet engines
Neutron Electric Dipole Moment from Beyond the Standard Model
Tanmoy Bhattacharya; Vincenzo Cirigliano; Rajan Gupta
2012-12-20
We discuss the phenomenology of neutron Electric Dipole Moment from the Standard Model and beyond, and identify the matrix elements most necessary to connect the current and forthcoming experiments with phenomenology. We then describe lattice techniques for calculating these matrix elements
On shielding of nuclear electric dipole moments in atoms
V. F. Dmitriev; I. B. Khriplovich; R. A. Sen'kov
2005-04-08
We demonstrate explicitly that some recent calculations of atomic electric dipole moments (EDM) are incomplete. A contribution overlooked therein is pointed out. When included, it cancels exactly the result of those calculations, and thus restores the standard conclusions for nuclear EDM in atoms.
Moment free energies for polydisperse systems Peter Sollich \\Lambda
Sollich, Peter
Moment free energies for polydisperse systems Peter Sollich \\Lambda Department of Mathematics, King(oe). The free energy depends on all details of ae(oe), making the analysis of phase equilibria in such systems intractable. However, in many (especially meanfield) models the excess free energy only depends on a finite
Huang, Zhaocong; Chen, Qian; Zhai, Ya E-mail: jlwang@seu.edu.cn; Wang, Jinlan E-mail: jlwang@seu.edu.cn; Xu, Yongbing; Wang, Baoping
2015-05-04
The magnetic and transport properties of half metallic Fe{sub 3}O{sub 4}, which are sensitive to the stoichiometry, are the key issue for applications in spintronics. An anomalous enlargement of the saturation magnetic moment is found in a relatively thick sample of epitaxial Fe{sub 3}O{sub 4} film by post-growth oxidation method. The investigation of the thickness dependence of magnetic moment suggests that the enhanced magnetism moment may come from the existence of oxygen vacancies. First-principles calculations reveal that with oxygen vacancies in Fe{sub 3}O{sub 4} crystal the spin of Fe ions in the tetrahedron site near the vacancy is much easier to switch parallel to the Fe ions in the octahedron site by temperature disturbance, supported by the temperature dependence of magnetic moment of Fe{sub 3}O{sub 4} films in experiment.
Anomaly detection in thermal pulse combustors using symbolic time series analysis
Ray, Asok
pulse combustor. Results are presented to exemplify early detection of combustion instability due339 Anomaly detection in thermal pulse combustors using symbolic time series analysis S Gupta1 for anomaly detection in thermal pulse combustors. The anomaly detection method has been tested on the time
Seasonal persistence of northern low-and middle-latitude anomalies of ozone and
Wirosoetisno, Djoko
Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other trace gases) Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other trace gases outputs online #12;Seasonal persistence of northern low- and middle-latitude anomalies of ozone and other
Adsorption-induced magnetic properties and metallic behavior of graphene
Zhou, Yungang; Zu, Xiaotao T.; Gao, Fei; Lv, H. F.; Xiao, Haiyan J.
2009-09-21
Magnetic properties and electronic structures of graphene with Cl, S, and P adsorption have been investigated using ab initio calculations. The adsorption of Cl leads to Fermi level shifting to valence band, which results in metallic graphene. A band gap of 0.6 eV emerges in a S-absorbed graphene, leading to the semiconducting graphene. The unpaired electrons in the absorbed P atom is polarized and thus, exhibits a magnetic moment of 0.86 ?B, while no magnetic moment has been observed after Cl and S adsorption. This demonstrates that the magnetic properties and conductive behavior of graphene can be modified via atom adsorption. Specially, P-absorbed graphene may be useful for spintronic applications, such as tunneling magnetoresistance.
Not Available
1994-08-01
This report discusses the following topics on superconducting magnets: D19B and -C: The next steps for a record-setting magnet; D20: The push beyond 10 T: Beyond D20: Speculations on the 16-T regime; other advanced magnets for accelerators; spinoff applications; APC materials development; cable and cabling-machine development; and high-{Tc} superconductor at low temperature.
Moment equations for chemical reactions on interstellar dust grains
Azi Lipshtat; Ofer Biham
2002-12-09
While most chemical reactions in the interstellar medium take place in the gas phase, those occurring on the surfaces of dust grains play an essential role. Chemical models based on rate equations including both gas phase and grain surface reactions have been used in order to simulate the formation of chemical complexity in interstellar clouds. For reactions in the gas phase and on large grains, rate equations, which are highly efficient to simulate, are an ideal tool. However, for small grains under low flux, the typical number of atoms or molecules of certain reactive species on a grain may go down to order one or less. In this case the discrete nature of the opulations of reactive species as well as the fluctuations become dominant, thus the mean-field approximation on which the rate equations are based does not apply. Recently, a master equation approach, that provides a good description of chemical reactions on interstellar dust grains, was proposed. Here we present a related approach based on moment equations that can be obtained from the master equation. These equations describe the time evolution of the moments of the distribution of the population of the various chemical species on the grain. An advantage of this approach is the fact that the production rates of molecular species are expressed directly in terms of these moments. Here we use the moment equations to calculate the rate of molecular hydrogen formation on small grains. It is shown that the moment equation approach is efficient in this case in which only a single reactive specie is involved. The set of equations for the case of two species is presented and the difficulties in implementing this approach for complex reaction networks involving multiple species are discussed.
Nature Macmillan Publishers Ltd 1998 generate a magnetic flux amounting to half
Paetzel, Mark
of the superconductor and so in the number of magnetic vortices threaded through the superconducting disc. Here, the PME. The magnetic moment of such a superconducting loop should indeedactlikeaparamagnet,asitalignspar- allel superconductors such as niobium. Again, to test ideas about how this could happen in mesoscopic grains, we need
Microscopic model for the magnetic subsystem in HoNi2B2C
Kalatsky, VA; Pokrovsky, Valery L.
1998-01-01
We demonstrate that the system of localized magnetic moments in HoNi2B2C can be described by the four-positional clock model. This model, at a proper choice of the coupling constants, yields several metamagnetic phases in magnetic field at zero...
Kraus, Jr., Robert H. (Los Alamos, NM); Zhou, Feng (Los Alamos, NM); Nolan, John P (Santa Fe, NM)
2007-06-19
The present invention is directed to processes of separating, analyzing and/or collecting selected species within a target sample by use of magnetic microspheres including magnetic particles, the magnetic microspheres adapted for attachment to a receptor agent that can subsequently bind to selected species within the target sample. The magnetic microspheres can be sorted into a number of distinct populations, each population with a specific range of magnetic moments and different receptor agents can be attached to each distinct population of magnetic microsphere.
Mechanism of magnetism in stacked nanographite with open shell electrons
Kikuo Harigaya; Toshiaki Enoki
2001-10-23
Antiferromagnetism in stacked nanographite is investigated with using the Hubbard-type models. The A-B stacking or the stacking near to that of A-B type is favorable for the hexagonal nanographite with zigzag edges, in order that magnetism appears. Next, we find that the open shell electronic structure can be an origin of the decreasing magnetic moment with the decrease of the inter-graphene distance, as experiments on adsorption of molecules suggest.
Pressure and magnetic field dependence of the antiferromagnetism of PrFe sub 4 P sub 12
Kuric, M.V.; Guertin, R.P. ); Torikachvili, M.S. ); Maple, M.B. ); Foner, S. )
1990-05-01
The compound PrFe{sub 4}P{sub 12}, which has the cubic LaFe{sub 4}P{sub 12} modified CoAs{sub 3}-type structure, orders antiferromagnetically, with {ital T}{sub {ital N}}=6.2 K and with several field-induced magnetic transitions for {ital T}{lt}{ital T}{sub {ital N}}, up to 5 T for {ital T}{much lt}{ital T}{sub {ital N}}. Heat capacity measurements show the transition is a bulk effect, with magnetic entropy consistent with a magnetic doublet or triplet crystal-field ground state. dc magnetization measurements, {ital M}({ital H}), at {ital T}=4.2 K up to 23 T reveal no further field-induced transitions, and {ital M}({ital H}) attains only 54% of the Pr{sup 3+} free-ion moment at highest fields. Pulsed field measurements of {ital dM}/{ital dH} at 4.2 K up to 45 T fail to resolve further transitions. The transition to the antiferromagnetic state is accompanied by a very sharp Suezaki--Mori-type electrical resistivity transition due to critical scattering of electrons by spin fluctuations. Hydrostatic pressure decreases {ital T}{sub {ital N}}, ({ital dT}{sub {ital N}}/{ital dP}={minus}0.11 K/kbar), in sharp contrast to the behavior for the isomorphic semiconducting ferromagnet, UFe{sub 4}P{sub 12} ({ital T}{sub {ital C}}=3.15 K; {ital dT}{sub {ital C}}/{ital dP}=+0.26 K/kbar). The field-induced magnetic transitions are also sharply reduced with pressure. The pressure dependence of the electrical resistivity showed a decrease in {ital T}{sub {ital N}}, with a concomitant decrease in the size of the Suezaki--Mori anomaly. The results are discussed in terms of crystal-field splittings of the Pr ion and possible hybridization effects.
Disentangling the Mn moments on different sublattices in the half-metallic ferrimagnet Mn3?xCoxGa
Klaer, P.; Jenkins, C.A.; Alijani, V.; Winterlik, J.; Balke, B.; Felser, C.; Elmers, H.J.
2011-05-03
Ferrimagnetic Mn{sub 3-x}Co{sub x}Ga compounds have been investigated by magnetic circular dichroism in x-ray absorption (XMCD). Compounds with x > 0.5 crystallize in the CuHg{sub 2}Ti structure. A tetragonal distortion of the cubic structure occurs for x {le} 0.5. For the cubic phase, magnetometry reveals a linearly increasing magnetization of 2x Bohr magnetons per formula unit obeying the generalized Slater-Pauling rule. XMCD confirms the ferrimagnetic character with Mn atoms occupying two different sublattices with antiparallel spin orientation and different degrees of spin localization and identifies the region 0.6 < x {le} 0.8 as most promising for a high spin polarization at the Fermi level. Individual Mn moments on inequivalent sites are compared to theoretical predictions.
H. Yan; B. Plaster
2011-04-07
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.
Measurement of the Magnet Blocks for SSRF Insertion Devices
He Yongzhou; Zhang Jidong; Zhou Qiaogen; Qian Zhenmei; Li Yang
2010-06-23
Two in-vacuum undulators IVU25s and one elliptically polarized undulator EPU100 have been developed for SSRF. Two IVU25s with the same hybrid design contain about 640 Sm{sub 2}Co{sub 17} magnet blocks and the dimension of blocks is 65 Wx25 Hx9 D. The EPU100 of the APPLE-II type contains about 690 NdFeB magnet blocks with the dimension of 35 Wx35 Hx25 D. This paper describes the magnetic measurements of these magnet blocks with the Helmholtz coil measurement system for IVU25 magnet blocks and the Hall probe measurement system for EPU100 magnet blocks. The measured maximum magnetic moment deviation and the maximum angle deviation are less than {+-}1.0% and 1.1 deg. respectively both for Sm{sub 2}Co{sub 17} blocks and NdFeB blocks and satisfy the specifications of undulators.
${\\cal N} = 1$ Euler Anomaly Flow from Dilaton Effective Action
Prochazka, Vladimir
2015-01-01
We consider ${\\cal N} =1$ supersymmetric gauge theories in the conformal window. The running of the gauge coupling is absorbed into the metric by applying a suitable matter superfield- and Weyl-transformation. The computation becomes equivalent to one of a free theory in a curved background carrying the information of the renormalisation group flow. We use the techniques of conformal anomaly matching and dilaton effective action, by Komargodski and Schwimmer, to rederive the difference of the Euler anomaly coefficient $\\Delta a \\equiv a_{\\rm UV} - a_{\\rm IR} $ for the ${\\cal N} =1$ theory. The structure of $\\Delta a $ is therefore in one-to-one correspondence with the Wess-Zumino dilaton action.
Anomaly-Free Supersymmetric Models in Six Dimensions
John H. Schwarz
1995-12-11
The conditions for the cancellation of all gauge, gravitational, and mixed anomalies of $N=1$ supersymmetric models in six dimensions are reviewed and illustrated by a number of examples. Of particular interest are models that cannot be realized perturbatively in string theory. An example of this type, which we verify satisfies the anomaly cancellation conditions, is the K3 compactification of the $SO(32)$ theory with small instantons recently proposed by Witten. When the instantons coincide it has gauge group $SO(32) \\times Sp(24)$. Two new classes of models, for which non-perturbative string constructions are not yet known, are also presented. They have gauge groups $SO(2n+8)\\times Sp(n)$ and $SU(n)\\times SU(n)$, where $n$ is an arbitrary positive integer.
Anomaly and the self-energy of electric charges
Valeri P. Frolov; Andrei Zelnikov
2012-10-26
We study the self energy of a charged particle located in a static D-dimensional gravitational field. We show that the energy functional for this problem is invariant under an infinite dimensional (gauge) group of transformations parameterized by one scalar function of (D-1)-variables. We demonstrate that the problem of the calculation of the self energy for a pointlike charge is equivalent to the calculation of the fluctuations $$ for an effective (D-1)-dimensional Euclidean quantum field theory. Using point-splitting regularization we obtain an expression for the self energy and show, that it possesses anomalies. Explicit calculation of the self energy and its anomaly is done for the higher dimensional Majumdar-Papapetrou spacetimes.
Title nd authors) Theory of Random Anisotropic Magnetic Alloys
that is of interest is their significance for the understanding of the rare earth metals. A number of experiments by Millhouse and Koehler , Nd-Pr by Lebech et al. , while a number of dilutions of rare earth metals 6 ) with Y rare earth metals in which the crystal field quenching of the magnetic moments to a good approximation
Identifying Isotropic Events Using a Regional Moment Tensor Inversion
Dreger, D S; Ford, S R; Walter, W R
2009-08-03
In our previous work the deviatoric and isotropic source components for 17 explosions at the Nevada Test Site, as well as 12 earthquakes and 4 collapses in the surrounding region of the western US, were calculated using a regional time-domain full waveform inversion for the complete moment tensor (Dreger et al., 2008; Ford et al., 2008; Ford et al., 2009a). The events separate into specific populations according to their deviation from a pure double-couple and ratio of isotropic to deviatoric energy. The separation allows for anomalous event identification and discrimination between explosions, earthquakes, and collapses. Confidence regions of the model parameters are estimated from the data misfit by assuming normally distributed parameter values. We developed a new Network Sensitivity Solution (NSS) in which the fit of sources distributed over a source-type plot (Hudson et al., 1989) show the resolution of the source parameters. The NSS takes into account the unique station distribution, frequency band, and signal-to-noise ratio of a given event scenario. The NSS compares both a hypothetical pure source (for example an explosion or an earthquake) and the actual data with several thousand sets of synthetic data from a uniform distribution of all possible sources. The comparison with a hypothetical pure source provides the theoretically best-constrained source-type region for a given set of stations, and with it one can determine whether further analysis with the data is warranted. We apply the NSS to a NTS nuclear explosion, and earthquake, as well as the 2006 North Korean explosion, and a nearby earthquake. The results show that explosions and earthquakes are distinguishable, however the solution space depends strongly on the station coverage. Finally, on May 25, 2009 a second North Korean test took place. Our preliminary results show that the explosive nature of the event may be determined using the regional distance moment tensor method. Results indicate that the 2009 event is approximately 5-6 times larger than the earlier test, with an isotropic moment of about 1.8e+22 dyne cm. We perform a series of inversions for pure double-couple, pure explosion, combined double-couple and explosion, full moment tensor, and damped moment tensor inversions to assess the resolution of the isotropic moment of the event.
Geometric Phase and Chiral Anomaly in Path Integral Formulation
Kazuo Fujikawa
2007-11-16
All the geometric phases, adiabatic and non-adiabatic, are formulated in a unified manner in the second quantized path integral formulation. The exact hidden local symmetry inherent in the Schr\\"{o}dinger equation defines the holonomy. All the geometric phases are shown to be topologically trivial. The geometric phases are briefly compared to the chiral anomaly which is naturally formulated in the path integral.
Structure order, local potentials, and physical anomalies of water ice
Chang Q Sun
2014-07-11
Hydrogen-bond forms a pair of asymmetric, coupled, H-bridged oscillators with ultra-short-range interactions and memory. hydrogen bond cooperative relaxation and the associated binding electron entrapment and nonbonding electron polarization discriminate water and ice from other usual materials in the physical anomalies. As a strongly correlated fluctuating system, water prefers the statistically mean of tetrahedrally-coordinated structure with a supersolid skin that is elastic, polarized, ice like, hydrophobic, with 3/4 density.
Automatic anomaly detection in high energy collider data
Simon de Visscher; Michel Herquet
2011-04-13
We address the problem of automatic anomaly detection in high energy collider data. Our approach is based on the random generation of analytic expressions for kinematical variables, which can then be evolved following a genetic programming procedure to enhance their discriminating power. We apply this approach to three concrete scenarios to demonstrate its possible usefulness, both as a detailed check of reference Monte-Carlo simulations and as a model independent tool for the detection of New Physics signatures.
Conjecture on the physical implications of the scale anomaly
Hill, Christopher T.; /Fermilab
2005-10-01
Murray Gell-Mann, after co-inventing QCD, recognized the interplay of the scale anomaly, the renormalization group, and the origin of the strong scale, {Lambda}{sub QCD}. I tell a story, then elaborate this concept, and for the sake of discussion, propose a conjecture that the physical world is scale invariant in the classical, {h_bar}, limit. This principle has implications for the dimensionality of space-time, the cosmological constant, the weak scale, and Planck scale.
Tailoring superelasticity of soft magnetic materials
Peet Cremer; Hartmut Löwen; Andreas M. Menzel
2015-08-04
Embedding magnetic colloidal particles in an elastic polymer matrix leads to smart soft materials that can reversibly be addressed from outside by external magnetic fields. We discover a pronounced nonlinear superelastic stress-strain behavior of such materials. It results from a combination of two stress-induced transitions: a detachment transition of embedded particle aggregates as well as a reorientation transition of magnetic moments. The superelastic regime can be reversibly tuned or even be switched on and off by external magnetic fields and thus be tailored during operation. Similarities to the superelastic behavior of shape-memory alloys suggest analogous applications, with the additional benefit of reversible switchability and a higher biocompatibility of soft materials.
On the possible onset of the Pioneer anomaly
Michael R. Feldman; John D. Anderson
2015-06-24
We explore the possibility that the observed onset of the Pioneer anomaly after Saturn encounter by Pioneer 11 is not necessarily due to mismodeling of solar radiation pressure but instead reflects a physically relevant characteristic of the anomaly itself. We employ the principles of a recently proposed cosmological model termed "the theory of inertial centers" along with an understanding of the fundamental assumptions taken by the Deep Space Network (DSN) to attempt to model this sudden onset. Due to an ambiguity that arises from the difference in the DSN definition of expected light-time with light-time according to the theory of inertial centers, we are forced to adopt a seemingly arbitrary convention to relate DSN-assumed clock-rates to physical clock-rates for this model. We offer a possible reason for adopting the convention employed in our analysis; however, we remain skeptical. Nevertheless, with this convention, one finds that this theory is able to replicate the previously reported Hubble-like behavior of the "clock acceleration" for the Pioneer anomaly as well as the sudden onset of the anomalous acceleration after Pioneer 11 Saturn encounter. While oscillatory behavior with a yearly period is also predicted for the anomalous clock accelerations of both Pioneer 10 and Pioneer 11, the predicted amplitude is an order of magnitude too small when compared with that reported for Pioneer 10.
Observation of the Chern-Simons gauge anomaly
Sunil Mittal; Sriram Ganeshan; Jingyun Fan; Abolhassan Vaezi; Mohammad Hafezi
2015-04-22
Topological Quantum Field Theories (TQFTs) are powerful tools to describe universal features of topological orders. A hallmark example of a TQFT is the 2+1 D Chern-Simons (CS) theory which describes topological properties of both integer and fractional quantum Hall effects. The gauge invariant form of the CS theory with boundaries, encompassing both edge and bulk terms, provides an unambiguous way to relate bulk topological invariants to the edge dynamics. This bulk-edge correspondence is manifested as a gauge anomaly of the chiral dynamics at the edge, and provides a direct insight into the bulk topological order. Such an anomaly has never been directly observed in an experiment. In this work, we experimentally implement the integer quantum Hall model in a photonic system, described by the corresponding CS theory. By selectively manipulating and probing the edge, we exploit the gauge anomaly of the CS theory, for the first time. The associated spectral edge flow allows us to unambiguously measure topological invariants, i.e., the winding number of the edge states. This experiment provides a new approach for direct measurement of topological invariants, independent of the microscopic details, and thus could be extended to probe strongly correlated topological orders.
An Analysis of Anomaly Cancellation for Theories in D=10
Andrea Antonelli
2015-07-21
We prove that the swampland for D=10 N=1 SUGRA coupled to D=10 N=1 SYM is only populated by U(1)^496 and E_8 x U(1)^248. With this goal in mind, we review the anomalies for classical and exceptional groups, retrieving trace identities up to the sixth power of the curvature for each class of groups. We expand this idea for low-dimensional groups, for which the trace of the sixth power is known to factorize, and we retrieve such factorization. We obtain the total anomaly polynomials for individual low dimensional groups and combinations of them and finally we investigate their non-factorization, in such a way that U(1)^496and E_8 xU(1)^248 are non-trivially shown to be the only anomaly-free theories allowed in D=10. Using the method developed for checking the factorization of gauge theories, we retrieve the Green-Schwarz terms for the two theories populating the swampland.
Anomaly Mediated Gaugino Mass and Path-Integral Measure
Keisuke Harigaya; Masahiro Ibe
2014-09-16
In recent years, there have been controversy concerning the anomaly mediated gaugino mass in the superspace formalism of supergravity. In this paper, we reexamine the gaugino mass term in this formalism by paying particular attention to symmetry which controls gaugino masses in supergravity. We first discuss super-Diffeomorphism invariance of path-integral measures of charged superfields. As we will show, the super-Diffeomorphism invariant measure is not invariant under a super-Weyl transformation, which is the origin of the anomaly mediated gaugino mass. We show how the anomaly mediated gaugino mass is expressed as a local operator in a Wilsonian effective action in a super-Diffeomorphism covariant way. We also obtain a gaugino mass term independent of the gauge choice of the fictitious super-Weyl symmetry in the super-Weyl compensator formalism, which reproduces the widely accepted result. Besides, we discuss how to reconcile the gaugino mass term in the local Wilsonian effective action and the gaugino mass term appearing in a non-local 1PI quantum effective action.
Revealing the Degree of Magnetic Frustration by Non-Magnetic Impurities
Not Available
2011-08-12
Imaging the magnetic fields around a non-magnetic impurity can provide a clear benchmark for quantifying the degree of magnetic frustration. Focusing on the strongly frustrated J{sub 1}-J{sub 2} model and the spatially anisotropic J{sub 1a}-J{sub 1b}-J{sub 2} model, very distinct low energy behaviors reflect different levels of magnetic frustration. In the J{sub 1}-J{sub 2} model, bound magnons appear trapped near the impurity in the ground state and strongly reduce the ordered moments for sites proximal to the impurity. In contrast, local moments in the J{sub 1a}-J{sub 1b}-J{sub 2} model are enhanced on the impurity neighboring sites. These theoretical predictions can be probed by experiments such as nuclear magnetic resonance and scanning tunneling microscopy, and the results can elucidate the role of frustration in antiferromagnets and help narrow the possible models to understand magnetism in the iron pnictdies.
Comment on ``Lattice QCD analysis of the strangeness magnetic moment of the nucleon''
C. W. Wong
2002-09-04
The recent chirally extrapolated result of Leinweber and Thomas [Phys. Rev. D {\\bf 62}, 074505 (2000), or LT] for the nucleon strangeness form factor G_M^s(0)= -0.16 \\pm 0.18 \\mu_N differs markedly from the earlier result -0.75 \\pm 0.30 \\mu_N obtained by Leinweber [Phys. Rev. D {\\bf 53}, 5115 (1996)] from the same lattice data. An unresolved problem in the LT analysis of lattice data is identified and addressed. A value of G_M^s(0) = -0.55 \\pm 0.37 \\mu_N is obtained at R^s_d = 0.55 by extrapolating only the nucleon isoscalar lattice data.
Predicted giant magnetic moment on non-{n0m} surfaces of d-wave superconductors
Hu, Chia-Ren; Yan, XZ.
1999-01-01
! is calculated using the Blonder-Tinkham-Klapwijk formalism:14,15 G52 \\2 4qF E 0 ` qdqE 2p/2 p/2 dfq cos f m 3H ( s5? ,? f 8~se1eV !@11As~e ,f!2Bs~e ,f!#J , ~8! where f is the angle between q and the x axis, e(s ,q ,f) is given in the previous... paragraph, qF[(2mEF)1/2/\\ , f (e)[1/@exp(e/kBT)11#, and As[uasu2, Bs[ubsu2. For nu- merical calculation, we take D0 /EF50.08 as a typical value for HTSC?s. The dimensionless barrier parameter is Z 5H/\\Am/2EF.14 Figure 1 gives G as a function of V at Z...
X-ray detection of transient magnetic moments induced by a spin current in
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Moment enhancement in dilute magnetic semiconductors: MnxSi1-x with x =
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Moment enhancement in dilute magnetic semiconductors: MnxSi1-x with x =
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Moment transport equations and their application to the perturbed universe
Sierra, Carlos A
2015-01-01
There are many inflationary models that allow the formation of the large-scale structure of the observable universe. The non-gaussianity parameter $f_{NL}$ is a useful tool to discriminate among these cosmological models when comparing the theoretical predictions with the satellite survey results like those from WMAP and Planck. The goal of this proceeding contribution is to review the moment transport equations methodology and the subsequent calculation of the $f_{NL}$ parameter.
The second moment of the pion light cone wave function
Luigi del Debbio; Massimo di Pierro; Alex Dougall
2003-09-25
We present a preliminary result for second moment of the light cone wave function of the pion. This parameter is the subject of a discrepancy between theoretical predictions (coming from lattice and sum rules) and a recent experimental result (that remarkably agrees with purely perturbative predictions). In this work we exploit lattice hypercubic symmetries to remove power divergences and, moreover, implement a full 1-loop matching for all the contributing operators.
Convex Duality and Entropy-Based Moment Closures ...
2007-11-19
A common method for constructing a function from a finite set of moments is to .... S(g) ? 0 ,. (6) with equality if and only if C(g) = 0. In such cases, g is said to ... are positive scalars and u ? Rd. In this way, H acts as a Lyapunov functional for (2). ..... conservation laws for mass, momentum, and energy which are given by the.
Molecular multipole moments of water molecules in ice Ih
Batista, E.R. [Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195-1560 (United States)] [Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195-1560 (United States); [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States); Xantheas, S.S. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 906 Battelle Boulevard, PO Box 999, MS K1-96, Richland, Washington 99352 (United States)] [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 906 Battelle Boulevard, PO Box 999, MS K1-96, Richland, Washington 99352 (United States); Jonsson, H. [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States)] [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States)
1998-09-01
We have used an induction model including dipole, dipole{endash}quadrupole, quadrupole{endash}quadrupole polarizability and first hyperpolarizability as well as fixed octopole and hexadecapole moments to study the electric field in ice. The self-consistent induction calculations gave an average total dipole moment of 3.09 D, a 67{percent} increase over the dipole moment of an isolated water molecule. A previous, more approximate induction model study by Coulson and Eisenberg [Proc. R. Soc. Lond. A {bold 291}, 445 (1966)] suggested a significantly smaller average value of 2.6 D. This value has been used extensively in recent years as a reference point in the development of various polarizable interaction potentials for water as well as for assessment of the convergence of water cluster properties to those of bulk. The reason for this difference is not due to approximations made in the computational scheme of Coulson and Eisenberg but rather due to the use of less accurate values for the molecular multipoles in these earlier calculations. {copyright} {ital 1998 American Institute of Physics.}
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.
2014-11-13
The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to themore »theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.« less
Malik, V.; Goodwill, J.; Mallapragada, S.; Prozorov, T.; Prozorov, R.
2014-11-13
The rate of heating of a water-based colloid of uniformly sized 15 nm magnetic nanoparticles by high-amplitude and high-frequency ac magnetic field induced by the resonating LC circuit (nanoTherics Magnetherm) was measured. The results are analyzed in terms of specific energy absorption rate (SAR). Fitting field amplitude and frequency dependences of SAR to the linear response theory, magnetic moment per particles was extracted. The value of magnetic moment was independently evaluated from dc magnetization measurements (Quantum Design MPMS) of a frozen colloid by fitting field-dependent magnetization to Langevin function. The two methods produced similar results, which are compared to the theoretical expectation for this particle size. Additionally, analysis of SAR curves yielded effective relaxation time.
Hel-Or, Yacov
] utilized sparse representations to analyze stochastic processes over graphs for anomaly detection in SmartGrids
Kerns, J.A.; Stone, R.R.; Fabyan, J.
1987-10-06
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines. 3 figs.
Kerns, John A. (Livermore, CA); Stone, Roger R. (Walnut Creek, CA); Fabyan, Joseph (Livermore, CA)
1987-01-01
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient magnetic field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.
SIMULATION OF BLOWING SNOW IN THE CANADIAN ARCTIC USING A DOUBLE-MOMENT MODEL
Dery, Stephen
SIMULATION OF BLOWING SNOW IN THE CANADIAN ARCTIC USING A DOUBLE-MOMENT MODEL STEPHEN J. DÉRY and M the development of a double-moment model of blowing snow and its application to the Canadian Arctic. We first snow mixing ratio and total particle num- bers, both moments of particles that are gamma
Electronic structure and magnetic behavior of UMn/sub 2/ and UFe/sub 2/
Boring, A.M.; Albers, R.C.; Schadler, G.H.; Lawson, A.C.; Weinberger, P.; Christensen, N.E.
1987-10-01
The electronic structure of UMn/sub 2/ and UFe/sub 2/ has been determined using the first-principles self-consistent spin-polarized scalar-relativistic linear muffin-tin-orbital method. The calculations were performed at several lattice spacings for these materials in the C15 (cubic Laves phase) crystal structure. In agreement with experimental data it is found that UMn/sub 2/ is almost nonmagnetic (small moments on the sites) whereas in UFe/sub 2/ both U and Fe sites have appreciable moments. Furthermore, the magnetism in these systems is determined by exchange splitting and not by charge-transfer effects. The calculated moments in UFe/sub 2/ are larger at the U sites than those seen experimentally. The total moment in UFe/sub 2/ is somewhat insensitive to changes in lattice spacing (over the limited range determined) while the moments on individual sites are very sensitive to this variation.
Magnetic vortex crystal formation in the antidot complement of square artificial spin ice
Araujo, C. I. L. de Silva, R. C.; Ribeiro, I. R. B.; Nascimento, F. S.; Felix, J. F.; Ferreira, S. O.; Moura-Melo, W. A.; Pereira, A. R.; Mól, L. A. S.
2014-03-03
We have studied ferromagnetic nickel thin films patterned with square lattices of elongated antidots that are negative analogues of square artificial spin ice. Micromagnetic simulations and direct current magnetic moment measurements reveal in-plane anisotropy of the magnetic hysteresis loops, and the formation of a dense array of magnetic vortices with random polarization and chirality. These multiply-connected antidot arrays could be superior to lattices of disconnected nanodisks for investigations of vortex switching by applied electric current.
High-resolution multifluid simulations of the plasma environment near the Martian magnetic anomalies
Harnett , Erika
] and solar wind electrons rapidly lose energy through impact ionization with exospheric neutrals [Crider et simulations of the solar wind interaction at Mars during the southern hemisphere summer solstice indicate, with less solar wind and more of ionospheric origin. The solar wind density is reduced by a factor of 3
Kerns, J.A.; Stone, R.R.; Fabyan, J.
1985-02-12
A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.
Spontaneous Liquid Crystal and Ferromagnetic Ordering of Colloidal Magnetic Nanoplates
Min Shuai; Arthur Klittnick; Yongqiang Shen; Gregory P. Smith; Michael R. Tuchband; Chenhui Zhu; Rolfe G. Petschek; Alenka Mertelj; Darja Lisjak; Martin ?opi?; Joseph E. Maclennan; Matthew A. Glaser; Noel A. Clark
2015-10-07
Ferrofluids are familiar as colloidal suspensions of ferromagnetic nanoparticles in aqueous or organic solvents. The dispersed particles are randomly oriented but their moments become aligned if a magnetic field is applied, producing a variety of exotic and useful magneto-mechanical effects. A longstanding interest and challenge has been to make such suspensions macroscopically ferromagnetic, that is having uniform magnetic alignment in absence of a field. Here we report a fluid suspension of magnetic nanoplates which spontaneously aligns into an equilibrium nematic liquid crystal phase that is also macroscopically ferromagnetic. Its zero-field magnetization produces distinctive magnetic self-interaction effects, including liquid crystal textures of fluid block domains arranged in closed flux loops, and makes this phase highly sensitive, with it dramatically changing shape even in the Earth's magnetic field.
Magnetic Fields Boosted by Gluon Vortices in Color Superconductivity
Efrain J. Ferrer; Vivian de la Incera
2006-08-28
We investigate the effects of an external magnetic field in the gluon dynamics of a color superconductor with three massless quark flavors. In the framework of gluon mean-field theory at asymptotic densities, we show that the long-range component $\\widetilde{H}$ of the external magnetic field that penetrates the CFL phase produces an instability when its strength becomes larger than the Meissner mass of the charged gluons. As a consequence, the magnetic field causes the formation of a vortex state characterized by the condensation of charged gluons and the creation of magnetic flux tubes. Inside the flux tubes the magnetic field is stronger than the applied one. This antiscreening effect is connected to the anomalous magnetic moment of the gluon field. We suggest how this same mechanism could serve to remove the chromomagnetic instabilities existing in gapless color superconductivity.
Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)
2010-11-16
A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.
On the vacuum fluctuations, Pioneer Anomaly and Modified Newtonian Dynamics
Dragan Slavkov Hajdukovic
2011-02-08
We argue that the so-called "Pioneer Anomaly" is related to the quantum vacuum fluctuations. Our approach is based on the hypothesis of the gravitational repulsion between matter and antimatter, what allows considering, the virtual particle-antiparticle pairs in the physical vacuum, as gravitational dipoles. Our simplified calculations indicate that the anomalous deceleration of the Pioneer spacecrafts could be a consequence of the vacuum polarization in the gravitational field of the Sun. At the large distances, the vacuum polarization by baryonic matter could mimic dark matter what opens possibility that dark matter do not exist, as advocated by the Modified Newtonian Dynamics (MOND).
Electromagnetic triangle anomaly and neutral pion condensation in QCD vacuum
Cao, Gaoqing
2015-01-01
We study the QCD vacuum structure under the influence of an electromagnetic field with a nonzero second Lorentz invariant $I_2=\\vec{E}\\cdot{\\vec B}$. We show that the presence of $I_2$ can induce neutral pion ($\\pi^0$) condensation in the QCD vacuum through the electromagnetic triangle anomaly. Within the frameworks of chiral perturbation theory at leading small-momenta expansion as well as the Nambu--Jona-Lasinio model at leading $1/N_c$ expansion, we quantify the dependence of the $\\pi^0$ condensate on $I_2$. The stability of the $\\pi^0$-condensed vacuum against the Schwinger charged pair production due to electric field is also discussed.
Investigating the Spectral Anomaly with Different Reactor Antineutrino Experiments
Christian Buck; Antoine P. Collin; Julia Haser; Manfred Lindner
2015-12-21
The spectral shape of reactor antineutrinos measured in recent experiments shows anomalies in the neutrino flux predictions. New precision measurements of the reactor neutrino spectra as well as more complete input in nuclear data bases are needed to resolve the observed discrepancies between flux models and experimental results. We combine experiments at reactors which are highly enriched in ${}^{235}$U with commercial reactors with typically lower enrichment to gain new insights into the origin of the anomalous neutrino spectrum. As an example, we discuss the option of a direct comparison of the measured shape in the currently running Double Chooz near detector and the upcoming Stereo experiment.
Ward identities and chiral anomalies for coupled fermionic chains
Costa, L. C.; Ferraz, A.; Mastropietro, Vieri
2013-12-15
Coupled fermionic chains are usually described by an effective model written in terms of bonding and anti-bonding fermionic fields with linear dispersion in the vicinities of the respective Fermi points. We derive for the first time exact Ward Identities (WI) for this model, proving the existence of chiral anomalies which verify the Adler-Bardeen non-renormalization property. Such WI are expected to play a crucial role in the understanding of the thermodynamic properties of the system. Our results are non-perturbative and are obtained analyzing Grassmann functional integrals by means of constructive quantum field theory methods.
Muon g-2 Anomaly and Dark Leptonic Gauge Boson
Lee, Hye-Sung [W& M
2014-11-01
One of the major motivations to search for a dark gauge boson of MeV-GeV scale is the long-standing muon g-2 anomaly. Because of active searches such as fixed target experiments and rare meson decays, the muon g-2 favored parameter region has been rapidly reduced. With the most recent data, it is practically excluded now in the popular dark photon model. We overview the issue and investigate a potentially alternative model based on the gauged lepton number or U(1)_L, which is under different experimental constraints.
A search for anomalies in the palladium-deuterium system
Gillespie, D.J.; Kamm, G.N.; Ehrlich, A.C. ); Mart, P.L. )
1989-12-01
A polycrystalline palladium rod is electrolytically charged with deuterium up to a deuterium/palladium ratio of 0.81 while several sample parameters are simultaneously measured in situ, including electrical resistivity, sample dimensions, cell temperature, and neutron production. Various charging rates are used in an attempt to provoke any anomalous behavior, such as a previously unknown crystallographic or chemical phase change, that might account for reports of heat or neutron production. Neither the electrical resistivity nor sample dimensions manifest evidence of any anomaly.
Orbital magnetism of mesoscopic metals; Beyond the perturbation theory
Serota, R.A. (Cincinnati Univ., OH (United States). Dept. of Physics)
1992-10-10
In this paper, the authors extend the authors' investigation of orbital magnetic response of mesoscopic metallic systems to the limit of temperature and inelastic level broadening being comparable or less than the average interlevel spacing. The authors address the role of level repulsion and derive a level density correlation function which interpolates between the perturbation result and the Wigner-Dyson statistics. The authors plot out the magnetic field dependence of the sample magnetic moment for the entire range of experimentally relevant temperatures. The authors briefly discuss the relationship of our results to quantum chaos.
The magnetic structure of EuCu2Sb2
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Ryan, D. H.; Cadogan, J. M.; Anand, V. K.; Johnston, D. C.; Flacau, R.
2015-05-06
Antiferromagnetic ordering of EuCu2Sb2 which forms in the tetragonal CaBe2Ge2-type structure (space group P4/nmm #129) has been studied using neutron powder diffraction and 151Eu Mössbauer spectroscopy. The room temperature 151Eu isomer shift of –12.8(1) mm/s shows the Eu to be divalent, while the 151Eu hyperfine magnetic field (Bhf) reaches 28.7(2) T at 2.1 K, indicating a full Eu2+ magnetic moment. Bhf(T) follows a smooth $S=\\frac{7}{2}$ Brillouin function and yields an ordering temperature of 5.1(1) K. Refinement of the neutron diffraction data reveals a collinear A-type antiferromagnetic arrangement with the Eu moments perpendicular to the tetragonal c-axis. As a result, themore »refined Eu magnetic moment at 0.4 K is 7.08(15) ?B which is the full free-ion moment expected for the Eu2+ ion with $S=\\frac{7}{2}$ and a spectroscopic splitting factor of g = 2.« less
D. B. Papadopoulos
2003-12-23
The equations which determine the response of a spinning charged particle moving in a uniform magnetic field to an incident gravitational wave are derived in the linearized approximation to general relativity. We verify that 1) the components of the 4-momentum, 4-velocity and the components of the spinning tensor, both electric and magnetic moments, exhibit resonances and 2) the co-existence of the uniform magnetic field and the GW are responsible for the resonances appearing in our equations. In the absence of the GW, the magnetic field and the components of the spin tensor decouple and the magnetic resonances disappear.
Casimir interaction from magnetically coupled eddy currents
Francesco Intravaia; Carsten Henkel
2009-09-06
We study the quantum and thermal fluctuations of eddy (Foucault) currents in thick metallic plates. A Casimir interaction between two plates arises from the coupling via quasi-static magnetic fields. As a function of distance, the relevant eddy current modes cross over from a quantum to a thermal regime. These modes alone reproduce previously discussed thermal anomalies of the electromagnetic Casimir interaction between good conductors. In particular, they provide a physical picture for the Casimir entropy whose nonzero value at zero temperature arises from a correlated, glassy state.
Casimir Interaction from Magnetically Coupled Eddy Currents
Intravaia, Francesco; Henkel, Carsten [Institut fuer Physik und Astronomie, Universitaet Potsdam, 14476 Potsdam (Germany)
2009-09-25
We study the quantum and thermal fluctuations of eddy (Foucault) currents in thick metallic plates. A Casimir interaction between two plates arises from the coupling via quasistatic magnetic fields. As a function of distance, the relevant eddy current modes cross over from a quantum to a thermal regime. These modes alone reproduce previously discussed thermal anomalies of the electromagnetic Casimir interaction between good conductors. In particular, they provide a physical picture for the Casimir entropy whose nonzero value at zero temperature arises from a correlated, glassy state.
Diffraction anomalies in hybrid structures based on chalcogenide-coated opal photonic crystals
Voronov, M M; Yakovlev, S A; Kurdyukov, D A; Golubev, V G
2014-01-01
The results of spectroscopic studies of the diffraction anomalies (the so-called resonant Wood anomalies) in spatially-periodic hybrid structures based on halcogenide (GST225)-coated opal films of various thickness are presented. A theoretical analysis of spectral-angular dependencies of the Wood anomalies has been made by means of a phenomenological approach using the concept of the effective refractive index of waveguiding surface layer.
Moments of the neutron g? structure function at intermediate Q²
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Solvignon-Slifer, Patricia H.
2015-07-15
We present new experimental results of the ³He spin structure function g? in the resonance region at Q² values between 1.2 and 3.0 (GeV/c)². Spin dependent moments of the neutron were then extracted.Our main result, the inelastic contribution to the neutron d? matrix element, was found to be small (Q²) = 2.4 (GeV/c)² and in agreement with the Lattice QCD calculation. The Burkhardt-Cottingham sum rule for ³He neutron was tested with the measured data and using the Wandzura-Wilczek relation for the low x unmeasured region.
Search for electric dipole moments at storage rings
Gerco Onderwater
2012-04-11
Permanent electric dipole moments (EDMs) violate parity and time reversal symmetry. Within the Standard Model (SM) they are many orders of magnitude below present experimental sensitivity. Many extensions of the SM predict much larger EDMs, which are therefore an excellent probe for the existence of "new physics". Until recently it was believed that only electrically neutral systems could be used for sensitive searches of EDMs. With the introduction of a novel experimental method, high precision for charged systems will be within reach as well. The features of this method and its possibilities are discussed.
Neutron Electric Dipole Moment from Beyond the Standard Model (Conference)
Office of Scientific and Technical Information (OSTI)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech Connect Nanomechanical switch for| SciTech Connect Neutron Electric Dipole Moment
Effects of continental-scale snow albedo anomalies on the wintertime Arctic oscillation
Allen, R. J; Zender, C. S
2010-01-01
to early?season Eurasian snow cover anomalies, Mon. Weather1973), The influence of average snow depth on monthly meanof Northern Hemisphere snow cover, Int. J. Climatol. , 16,
Phase Diagram and Waterlike Anomalies in Core-Softened Shoulder-Dumbbell
Barbosa, Marcia C. B.
). Consequently, very complex thermodynamic, dynamic or macroscopic features in principle could be captured density anomaly. Liquid sulfur displays a sharp minimum in the density (Sauer & Borst, 1967), related
Innovative Sensors for Pipeline Crawlers: Rotating Permanent Magnet Inspection
J. Bruce Nestleroth; Richard J. Davis; Stephanie Flamberg
2006-09-30
Internal inspection of pipelines is an important tool for ensuring safe and reliable delivery of fossil energy products. Current inspection systems that are propelled through the pipeline by the product flow cannot be used to inspect all pipelines because of the various physical barriers they may encounter. To facilitate inspection of these ''unpiggable'' pipelines, recent inspection development efforts have focused on a new generation of powered inspection platforms that are able to crawl slowly inside a pipeline and can maneuver past the physical barriers that limit internal inspection applicability, such as bore restrictions, low product flow rate, and low pressure. The first step in this research was to review existing inspection technologies for applicability and compatibility with crawler systems. Most existing inspection technologies, including magnetic flux leakage and ultrasonic methods, had significant implementation limitations including mass, physical size, inspection energy coupling requirements and technology maturity. The remote field technique was the most promising but power consumption was high and anomaly signals were low requiring sensitive detectors and electronics. After reviewing each inspection technology, it was decided to investigate the potential for a new inspection method. The new inspection method takes advantage of advances in permanent magnet strength, along with their wide availability and low cost. Called rotating permanent magnet inspection (RPMI), this patent pending technology employs pairs of permanent magnets rotating around the central axis of a cylinder to induce high current densities in the material under inspection. Anomalies and wall thickness variations are detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. This inspection method is an alternative to the common concentric coil remote field technique that induces low-frequency eddy currents in ferromagnetic pipes and tubes. Since this is a new inspection method, both theory and experiment were used to determine fundamental capabilities and limitations. Fundamental finite element modeling analysis and experimental investigations performed during this development have led to the derivation of a first order analytical equation for designing rotating magnetizers to induce current and positioning sensors to record signals from anomalies. Experimental results confirm the analytical equation and the finite element calculations provide a firm basis for the design of RPMI systems. Experimental results have shown that metal loss anomalies and wall thickness variations can be detected with an array of sensors that measure local changes in the magnetic field produced by the induced current flowing in the material. The design exploits the phenomenon that circumferential currents are easily detectable at distances well away from the magnets. Current changes at anomalies were detectable with commercial low cost Hall Effect sensors. Commercial analog to digital converters can be used to measure the sensor output and data analysis can be performed in real time using PC computer systems. The technology was successfully demonstrated during two blind benchmark tests where numerous metal loss defects were detected. For this inspection technology, the detection threshold is a function of wall thickness and corrosion depth. For thinner materials, the detection threshold was experimentally shown to be comparable to magnetic flux leakage. For wall thicknesses greater than three tenths of an inch, the detection threshold increases with wall thickness. The potential for metal loss anomaly sizing was demonstrated in the second benchmarking study, again with accuracy comparable to existing magnetic flux leakage technologies. The rotating permanent magnet system has the potential for inspecting unpiggable pipelines since the magnetizer configurations can be sufficiently small with respect to the bore of the pipe to pass obstructions that limit the application of many i
Primordial quantum nonequilibrium and large-scale cosmic anomalies
Samuel Colin; Antony Valentini
2015-06-12
We study incomplete relaxation to quantum equilibrium at long wavelengths, during a pre-inflationary phase, as a possible explanation for the reported large-scale anomalies in the cosmic microwave background (CMB). Our scenario makes use of the de Broglie-Bohm pilot-wave formulation of quantum theory, in which the Born probability rule has a dynamical origin. The large-scale power deficit could arise from incomplete relaxation for the amplitudes of the primordial perturbations. We show, by numerical simulations for a spectator scalar field, that if the pre-inflationary era is radiation dominated then the deficit in the emerging power spectrum will have a characteristic shape (an inverse-tangent dependence on wavenumber k, with oscillations). It is found that our scenario is able to produce a power deficit in the observed region and of the observed (approximate) magnitude for an appropriate choice of cosmological parameters. We also discuss the large-scale anisotropy, which might arise from incomplete relaxation for the phases of the primordial perturbations. We present numerical simulations for phase relaxation, and we show how to define characteristic scales for amplitude and phase nonequilibrium. The extent to which the data might support our scenario is left as a question for future work. Our results suggest that we have a potentially viable model that might explain two apparently independent cosmic anomalies by means of a single mechanism.
Rate of gravitational inflaton decay via gauge trace anomaly
Yuki Watanabe
2011-04-26
We analyze decay processes of the inflaton field, phi, during the coherent oscillation phase after inflation in f(phi)R gravity. It is inevitable that the inflaton decays gravitationally into gauge fields in the presence of f(phi)R coupling. We show a concrete calculation of the rate that the inflaton field decays into a pair of gauge fields via the trace anomaly. Comparing this new decay channel via the anomaly with the channels from the tree-level analysis, we find that the branching ratio crucially depends on masses and the internal multiplicities (flavor quantum number) of decay product particles. While the inflaton decays exclusively into light fields, heavy fields still play a role in quantum loops. We argue that this process in principle allows us to constrain the effects of arbitrary heavy particles in the reheating. We also apply our analysis to Higgs inflation, and find that the gravitational decay rate would never exceed gauge interaction decay rates if quantum gravity is unimportant.
Low-energy planar magnetic defects in BaFe2As2: Nanotwins, twins, antiphase, and domain boundaries
Khan, Suffian N. [Ames Laboratory; Alam, Aftab [Ames Laboratory; Johnson, Duane D. [Ames Laboratory
2013-11-27
In BaFe2As2, structural and magnetic planar defects begin to proliferate below the structural phase transition, affecting descriptions of magnetism and superconductivity. We study, using density-functional theory, the stability and magnetic properties of competing antiphase and domain boundaries, twins and isolated nanotwins (twin nuclei), and spin excitations proposed and/or observed. These nanoscale defects have a very low surface energy (22–210 m Jm?2), with twins favorable to the mesoscale. Defects exhibit smaller moments confined near their boundaries—making a uniform-moment picture inappropriate for long-range magnetic order in real samples. Nanotwins explain features in measured pair distribution functions so should be considered when analyzing scattering data. All these defects can be weakly mobile and/or can have fluctuations that lower assessed “ordered” moments from longer spatial and/or time averaging and should be considered directly.
Magnetic Fields in Quantum Degenerate Systems and in Vacuum
H. Perez Rojas; E. Rodriguez Querts
2006-12-28
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.
Fryberger, D.
1984-12-01
In this talk on magnetic monopoles, first the author briefly reviews some historical background; then, the author describes what several different types of monopoles might look like; and finally the author discusses the experimental situation. 81 references.
Position space CMB anomalies from multi-stream inflation
Wang, Yi, E-mail: yi.wang@ipmu.jp [Kavli Institute for the Physics and Mathematics of the Universe (WPI), Todai Institutes for Advanced Study, University of Tokyo, 5-1-5 Kashiwanoha, Kashiwa, Chiba 277-8583 (Japan)
2013-10-01
Temporary domain walls are produced during the bifurcation era of multi-stream inflation. The observational effects from such a domain wall to spectator field perturbations are calculated, and we expect the inflationary perturbations share similarities with the case of spectator field. A domain wall induces a preferred direction in the sky, affecting the angular distribution of perturbations. A correlated suppression of multipoles together with an alignment of multipole moments on the preferred direction are generated. Other observational aspects of multi-stream inflation, including hemispherical asymmetry and cold spot are also briefly reviewed.
Maxwell-Chern-Simons Hydrodynamics for the Chiral Magnetic Effect
Sener Ozonder
2011-07-20
The rate of vacuum changing topological solutions of the gluon field, sphalerons, is estimated to be large at the typical temperatures of heavy-ion collisions, particularly at the Relativistic Heavy Ion Collider. Such windings in the gluon field are expected to produce parity-odd bubbles, which cause separation of positively and negatively charged quarks along the axis of the external magnetic field. This chiral magnetic effect can be mimicked by Chern-Simons modified electromagnetism. Here we present a model of relativistic hydrodynamics including the effects of axial anomalies via the Chern-Simons term.
Alternating magnetic anisotropy of Li2(Li1–xTx)N(T=Mn,Fe,Co,andNi)
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jesche, A.; Ke, L.; Jacobs, J. L.; Harmon, B.; Houk, R. S.; Canfield, P. C.
2015-05-11
Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li2(Li1–xTx)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy plane?easy axis?easy plane?easy axis when progressing from T = Mn ? Fe ? Co ? Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model.more »As a result, the calculated magnetic anisotropies show surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.« less
Alternating magnetic anisotropy of Li 2 ( Li 1 - x T x ) N ( T = Mn , Fe , Co , and Ni )
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jesche, A.; Ke, L.; Jacobs, J. L.; Harmon, B.; Houk, R. S.; Canfield, P. C.
2015-05-01
Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li?(Li1-xTx)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy plane?easy axis?easy plane?easy axis when progressing from T = Mn ? Fe ? Co ? Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model.more »The calculated magnetic anisotropies show surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.« less
Alternating magnetic anisotropy of Li 2 ( Li 1 - x T x ) N ( T = Mn , Fe , Co , and Ni )
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Jesche, A.; Ke, L.; Jacobs, J. L.; Harmon, B.; Houk, R. S.; Canfield, P. C.
2015-05-01
Substantial amounts of the transition metals Mn, Fe, Co, and Ni can be substituted for Li in single crystalline Li?(Li1-xTx)N. Isothermal and temperature-dependent magnetization measurements reveal local magnetic moments with magnitudes significantly exceeding the spin-only value. The additional contributions stem from unquenched orbital moments that lead to rare-earth-like behavior of the magnetic properties. Accordingly, extremely large magnetic anisotropies have been found. Most notably, the magnetic anisotropy alternates as easy plane?easy axis?easy plane?easy axis when progressing from T = Mn ? Fe ? Co ? Ni. This behavior can be understood based on a perturbation approach in an analytical, single-ion model. The calculated magnetic anisotropies show surprisingly good agreement with the experiment and capture the basic features observed for the different transition metals.
Ito, Garrett
Gravity anomalies of the Northern Hawaiian Islands: Implications on the shield evolutions of Kauai reveal two positive residual gravity anomalies in the Northern Hawaiian Islands: one over Kaua'i, the other between the islands of Kaua'i and Ni'ihau. These gravitational highs are similar in size
Solar Flare Intermittency and the Earth's Temperature Anomalies Nicola Scafetta1,2
Scafetta, Nicola
Solar Flare Intermittency and the Earth's Temperature Anomalies Nicola Scafetta1,2 and Bruce J; published 17 June 2003) We argue that Earth's short-term temperature anomalies and the solar flare data sets that corresponds to the one that would be induced by the solar flare intermittency. The mean
Anomalies in 2008 Upwelled Water Properties on the Newport Hydrographic Line
Kurapov, Alexander
the Earth's rotation and southward winds drive warm and relatively fresh surface water offshore being of the start of sustained southward winds. A comparison of anomalies in ocean properties and cumulative along-shore wind stress anomalies during the upwelling season aims to quantify how the coastal ocean responds
Optical response of grating-coupler-induced intersubband resonances: The role of Wood's anomalies
Ludwig-Maximilians-Universität, München
Optical response of grating-coupler-induced intersubband resonances: The role of Wood's anomalies L of Wood's anomalies. S0163-1829 97 05403-9 I. INTRODUCTION The optical and electronic properties at, e.g., a modulation- doped semiconductor heterojunction have been widely stud- ied in the recent
Meridional movement of wind anomalies during ENSO events and their role in event termination
Santoso, Agus
Meridional movement of wind anomalies during ENSO events and their role in event termination Shayne), Meridional movement of wind anomalies during ENSO events and their role in event termination, Geophys. Res, setting up conditions favorable for the termination of ENSO warm events. The basic principles of the RDO
On the Persistence of Cold-Season SST Anomalies Associated with the Annular Modes
England, Matthew
On the Persistence of Cold-Season SST Anomalies Associated with the Annular Modes LAURA M. CIASTO fluxes, and Ekman currents on the persistence of cold-season extratropical sea surface temperature (SST. Observational analysis reveals that during the cold season, SST anomalies associated with the southern annular
Rossi, Fabrice
) and helping the engine owner to implement efficiently the adapted maintenance operations (fixing the source of the anomaly) are of crucial importance to reduce the costs attached to unscheduled maintenance. This paper a vast scientific literature [1]. Among the possible choices, statistical tech- niques for anomaly
Schellekens, Michel P.
reports have examined connections between these so-called El-Nino and La-Nina events and anomalies the anomalies and established indices of SST climate variations, such as the El-Nino Southern Oscillation in determining weather conditions(Chelton et. al.[4, 5]). The warm (El-Nino) and cold (La-Nina) deviations from
Geophys. J. Int. (1995) 122,982-990 Topography and geoid due to lithospheric mass anomalies
1995-01-01
the broad seismic velocity anomalies in the interior of the Earth. Geophysicists have related them). Nevertheless, the interpretation of the global geoid in terms of mantle mass anomalies was less successful topography undulations. However, geological records indicate that the relative sea-level variations recorded
Neutrino electromagnetic properties: new approach to oscillations in magnetic fields
Dmitriev, Alexander; Studenikin, Alexander
2015-01-01
Several new and interesting aspects of neutrino oscillations in a magnetic field are considered: 1) We develop a standard usually used approach to the neutrino spin oscillations in the neutrino mass basis and obtain the effective neutrino spin (and "spin-mass") oscillation Hamiltonian that can be used for description of the neutrino oscillations between different pairs of neutrino states with different masses and helicities; 2) We derive the exact solution of the Dirac equation for a massive neutrino with nonzero magnetic moment in the presence of a constant transversal magnetic field that is rotating along the direction of the neutrino propagation (the twisting magnetic field) and on the basis of the obtained energy spectrum the neutrino spin oscillation effective Hamiltonian is derive; 3) We develop a new approach to neutrino spin oscillations that is based on the description of the neutrino spin states with the corresponding spin operator that commutes with the neutrino dynamics Hamiltonian in the magnetic...
Superconnections, Anomalies and Non-BPS Brane Charges
Richard J. Szabo
2001-10-09
The properties of brane-antibrane systems and systems of unstable D-branes in Type II superstring theory are investigated using the formalism of superconnections. The low-energy open string dynamics is shown to be probed by generalized Dirac operators. The corresponding index theorems are used to compute the chiral gauge anomalies in these systems, and hence their gravitational and Ramond-Ramond couplings. A spectral action for the generalized Dirac operators is also computed and shown to exhibit precisely the expected processes of tachyon condensation on the brane worldvolumes. The Chern-Simons couplings are thereby shown to be naturally related to Fredholm modules and bivariant K-theory, confirming the expectations that D-brane charge is properly classified by K-homology.
Superconnections, Anomalies and Non-BPS Brane Charges
Szabó, R J
2001-01-01
The properties of brane-antibrane systems and systems of unstable D-branes in Type II superstring theory are investigated using the formalism of superconnections. The low-energy open string dynamics is shown to be probed by generalized Dirac operators. The corresponding index theorems are used to compute the chiral gauge anomalies in these systems, and hence their gravitational and Ramond-Ramond couplings. A spectral action for the generalized Dirac operators is also computed and shown to exhibit precisely the expected processes of tachyon condensation on the brane worldvolumes. The Chern-Simons couplings are thereby shown to be naturally related to Fredholm modules and bivariant K-theory, confirming the expectations that D-brane charge is properly classified by K-homology.
Theoretical calculations of magnetic order and anisotropy energies in molecular magnets
Pederson, M. R. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Porezag, D. V. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Kortus, J. [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States)] [Center for Computational Materials Science - 6392, Naval Research Laboratory, Washington, D.C. 20375-5000 (United States); Khanna, S. N. [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)] [Department of Physics, Virginia Commonwealth University, Richmond, Virginia 23284-2000 (United States)
2000-05-01
We present theoretical electronic structure calculations on the nature of electronic states and the magnetic coupling in the Mn{sub 12}O{sub 12} free cluster and the Mn{sub 12}O{sub 12}(RCOO){sub 16}(H{sub 2}O){sub 4} molecular magnetic crystal. The calculations have been performed with the all-electron full-potential NRLMOL code. We find that the free Mn{sub 12}O{sub 12} cluster relaxes to an antiferromagnetic cluster with no net moment. However, when coordinated by sixteen HCOO ligands and four H{sub 2}O groups, as it is in the molecular crystal, we find that the ferrimagnetic ordering and geometrical and magnetic structure observed in the experiments is restored. Local Mn moments for the free and ligandated molecular magnets are presented and compared to experiment. We identify the occupied and unoccupied electronic states that are most responsible for the formation of the large anisotropy barrier and use a recently developed full-space and full-potential method for calculating the spin-orbit coupling interaction and anisotropy energies. Our calculated second-order anisotropy energy is in excellent agreement with experiment. (c) 2000 American Institute of Physics.
Schiff Screening of Relativistic Nucleon Electric-Dipole Moments by Electrons
C. -P. Liu; J. Engel
2007-05-14
We show, at leading-order in the multipole expansion of the electron-nucleus interaction, that nucleon electric-dipole moments are completely shielded by electrons so that they contribute nothing to atomic electric-dipole moments, even when relativity in the nucleus is taken into account. It is well known that relativistic electron motion, by contrast, leads to dipole moments that are not screened; we discuss the reasons for the difference.
Bulk-Flow analysis for force and moment coefficients of a shrouded centrifugal compressor impeller
Gupta, Manoj Kumar
2005-08-29
and moments. The integral equations and the corresponding definitions for obtaining the reaction forces and moments are given in Childs? [8]. Rotordynamic coefficients are obtained by carrying out a least- square curve fit for the reaction forces and moments... ??????? 58 13 Damped eigenvalues with Wachel?s model????????????? 60 14 Damped eigenvalues with radially outward leakage on the back shroud for complete force and mo ment model????????????????. 63 15 Damped eigenvalues with radially inward...
Intrinsic Electric Dipole Moments of Paramagnetic Atoms: Rubidium and Cesium
H. S. Nataraj; B. K. Sahoo; B. P. Das; D. Mukherjee
2008-04-07
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.
Covariant spectator theory of np scattering: Deuteron quadrupole moment
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Gross, Franz
2015-01-26
The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently frommore »XEFT predictions to order N3LO.« less
Covariant Spectator Theory of np scattering: Deuteron Quadrupole Moment
Gross, Franz
2015-01-01
The deuteron quadrupole moment is calculated using two CST model wave functions obtained from the 2007 high precision fits to np scattering data. Included in the calculation are a new class of isoscalar np interaction currents automatically generated by the nuclear force model used in these fits. The prediction for model WJC-1, with larger relativistic P-state components, is 2.5% smaller that the experiential result, in common with the inability of models prior to 2014 to predict this important quantity. However, model WJC-2, with very small P-state components, gives agreement to better than 1%, similar to the results obtained recently from chiral effect field theory predictions to order next-to-next-to-next-to-leading order.
Frequency Domain Storage Ring Method for Electric Dipole Moment Measurement
Talman, Richard
2015-01-01
Precise measurement of the electric dipole moments (EDM) of fundamental charged particles would provide a significant probe of physics beyond the standard model. Any measurably large EDM would imply violation of both time reversal and parity conservation, with implications for the matter/anti-matter imbalance of the universe, not currently understood within the standard model. A frequency domain (i.e. difference of frequencies) method is proposed for measuring the EDM of electrons or protons or, with modifications, deuterons. Anticipated precision (i.e. reproducibility) is $10^{-30}\\,$e-cm for the proton EDM, with comparable accuracy (i.e. including systematic error). This would be almost six orders of magnitude smaller than the present upper limit, and will provide a stringent test of the standard model. Resonant polarimetry, made practical by the large polarized beam charge, is the key (most novel, least proven) element of the method. Along with the phase-locked, rolling polarization "Koop spin wheel," reso...
Comparison of moment-closure approximations for stochastic chemical kinetics
David Schnoerr; Guido Sanguinetti; Ramon Grima
2015-08-07
In recent years moment-closure approximations (MA) of the chemical master equation have become a popular method for the study of stochastic effects in chemical reaction systems. Several different MA methods have been proposed and applied in the literature, but it remains unclear how they perform with respect to each other. In this paper we study the normal, Poisson, log-normal and central-moment-neglect MAs by applying them to understand the stochastic properties of chemical systems whose deterministic rate equations show the properties of bistability, ultrasensitivity and oscillatory behaviour. Our results suggest that the normal MA is favourable over the other studied MAs. In particular we found that (i) the size of the region of parameter space where a closure gives physically meaningful results, e.g. positive mean and variance, is considerably larger for the normal closure than for the other three closures; (ii) the accuracy of the predictions of the four closures (relative to simulations using the stochastic simulation algorithm) is comparable in those regions of parameter space where all closures give physically meaningful results; (iii) the Poisson and log-normal MAs are not uniquely defined for systems involving conservation laws in molecule numbers. We also describe the new software package MOCA which enables the automated numerical analysis of various MA methods in a graphical user interface and which was used to perform the comparative analysis presented in this paper. MOCA allows the user to develop novel closure methods and can treat polynomial, non-polynomial, as well as time-dependent propensity functions, thus being applicable to virtually any chemical reaction system.
Network Sensitivity Solutions for Regional Moment Tensor Inversions
Ford, S R; Dreger, D S; Walter, W R
2009-06-05
Well-resolved moment tensor solutions reveal information about the sources of seismic waves. Here we introduce a new way of assessing confidence in the regional full moment tensor inversion via the introduction of the network sensitivity solution (NSS). The NSS takes into account the unique station distribution, frequency band, and signal-to-noise ratio of a given event scenario. The NSS compares both a hypothetical pure source (for example an explosion or an earthquake) and the actual data with several thousand sets of synthetic data from a uniform distribution of all possible sources. The comparison with a hypothetical pure source provides the theoretically best-constrained source-type region for a given set of stations, and with it one can determine whether further analysis with the data is warranted. The NSS that employs the actual data gives a direct comparison of all other source-types with the best-fit source. In this way, one can choose a threshold level of fit where the solution is comfortably constrained. The method is tested for the well-recorded nuclear test, JUNCTION, at the Nevada Test Site. Sources that fit comparably well to a hypothetical pure explosion recorded with no noise at the JUNCTION data stations have a large volumetric component and are not described well by a double-couple (DC) source. The NSS using the real data from JUNCTION is even more tightly constrained to an explosion since the data contains some energy that precludes fitting with any type of deviatoric source. We also calculate the NSS for the October 2006 North Korea test and a nearby earthquake, where the station coverage is poor and the event magnitude is small. The earthquake solution is very well fit by a DC source, and the best-fit solution to the nuclear test (M{sub W}4.1) is dominantly explosion.
Intrinsic chiral magnetic effect in Dirac semimetals due to dislocations
Chernodub, M N
2015-01-01
The dislocation in Dirac semimetal carries an emergent magnetic flux parallel to the dislocation axis. We show that due to the emergent magnetic field the dislocation accommodates a single fermion massless mode of the corresponding low-energy one-particle Hamiltonian. The mode is propagating along the dislocation with its spin directed parallel to the dislocation axis. In agreement with the chiral anomaly observed in Dirac semimetals, an external electric field results in the spectral flow of the one-particle Hamiltonian, in pumping of the fermionic quasiparticles out from vacuum, and in creating a nonzero axial (chiral) charge in the vicinity of the dislocation. In the presence of the chirality imbalance, the intrinsic magnetic field of the dislocation generates an electric current along the dislocation axis. We point out that this effect - which is an "intrinsic" analogue of the chiral magnetic effect - may experimentally reveal itself through transport phenomena in Dirac semimetals via the enhanced conduct...
Hanyk, Ladislav
Direct Volumetric Integration of the Time-Dependent Moment of Inertia for a Compressible of inertia tensor with volumetric integration. We present analytical formulae for evaluating the time
Royet, J.M.
2011-01-01
J. Royet, "Magnet Cable Manufacturing", oral presentation atDivision Magnet Cable Manufacturing J. Royet October 1990J I Magnet Cable Manufacturing* John Royet Accelerator &
CaMn2Al10: Itinerant Mn magnetism on the verge of magnetic order
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Steinke, L.; Simonson, J. W.; Yin, W. -G.; Smith, G. J.; Kistner-Morris, J. J.; Zellman, S.; Puri, A.; Aronson, M. C.
2015-07-24
We report the discovery of CaMn2Al10, a metal with strong magnetic anisotropy and moderate electronic correlations. Magnetization measurements find a Curie-Weiss moment of 0.83?B/Mn, significantly reduced from the Hund's rule value, and the magnetic entropy obtained from specific heat measurements is correspondingly small, only ? 9% of Rln2. These results imply that the Mn magnetism is highly itinerant, a conclusion supported by density functional theory calculations that find strong Mn-Al hybridization. Consistent with the layered nature of the crystal structure, the magnetic susceptibility ? is anisotropic below 20 K, with a maximum ratio of ?[010]/?[001] ? 3.5. A strong power-lawmore »divergence ?(T) ~ T–1.2 below 20 K implies incipient ferromagnetic order, an Arrott plot analysis of the magnetization suggests a vanishing low Curie temperature TC ~ 0. Our experiments indicate that CaMn2Al10 is a rare example of a system where the weak and itinerant Mn-based magnetism is poised on the verge of order.« less
Modified Magnetic Ground State in Nimn (2) O (4) Thin Films
Nelson-Cheeseman, B.B.; Chopdekar, R.V.; Iwata, J.M.; Toney, M.F.; Arenholz, E.; Suzuki, Y.; /SLAC
2012-08-23
The authors demonstrate the stabilization of a magnetic ground state in epitaxial NiMn{sub 2}O{sub 4} (NMO) thin films not observed in their bulk counterpart. Bulk NMO exhibits a magnetic transition from a paramagnetic phase to a collinear ferrimagnetic moment configuration below 110 K and to a canted moment configuration below 70 K. By contrast, as-grown NMO films exhibit a single magnetic transition at 60 K and annealed films exhibit the magnetic behavior found in bulk. Cation inversion and epitaxial strain are ruled out as possible causes for the new magnetic ground state in the as-grown films. However, a decrease in the octahedral Mn{sup 4+}:Mn{sup 3+} concentration is observed and likely disrupts the double exchange that produces the magnetic state at intermediate temperatures. X-ray magnetic circular dichroism and bulk magnetometry indicate a canted ferrimagnetic state in all samples at low T. Together these results suggest that the collinear ferrimagnetic state observed in bulk NMO at intermediate temperatures is suppressed in the as grown NMO thin films due to a decrease in octahedral Mn{sup 4+}, while the canted moment ferrimagnetic ordering is preserved below 60 K.
Modified magnetic ground state in NiMn2O4 thin films
Nelson-Cheeseman, B. B.; Chopdekar, R. V.; Toney, M. F.; Arenholz, E.; Suzuki, Y.; Iwata, J.M.
2010-08-03
We demonstrate the stabilization of a magnetic ground state in epitaxial NiMn2O4 (NMO) thin films not observed in their bulk counterpart. Bulk NMO exhibits a magnetic transition from a paramagnetic phase to a collinear ferrimagnetic moment configuration below 110 K and to a canted moment configuration below 70 K. By contrast, as-grown NMO films exhibit a single magnetic transition at 60 K and annealed films exhibit the magnetic behavior found in bulk. Cation inversion and epitaxial strain are ruled out as possible causes for the new magnetic ground state in the as-grown films. However, a decrease in the octahedral Mn{sup 4+}:Mn{sup 3+} concentration is observed and likely disrupts the double exchange that produces the magnetic state at intermediate temperatures. X-ray magnetic circular dichroism and bulk magnetometry indicate a canted ferrimagnetic state in all samples at low temperature. Together these results suggest that the collinear ferrimagnetic state observed in bulk NMO at intermediate temperatures is suppressed in the as grown NMO thin films due to a decrease in octahedral Mn{sup 4+} while the canted moment ferrimagnetic ordering is preserved below 60 K.
Electric and magnetic response to the continuum for A=7 isobars in a dicluster model
A. Mason; R. Chatterjee; L. Fortunato; A. Vitturi
2008-11-11
Mirror isobars $^7$Li and $^7$Be are investigated in a dicluster model. The magnetic dipole moments and the magnetic dipole response to the continuum are calculated in this framework. The magnetic contribution is found to be small with respect to electric dipole and quadrupole excitations even at astrophysical energies, at a variance with the case of deuteron. Energy weighted molecular sum rules are evaluated and a formula for the molecular magnetic dipole sum rule is found which matches the numerical calculations. Cross-sections for photo-dissociation and radiative capture as well as the S-factor for reactions of astrophysical significance are calculated with good agreement with known experimental data.
Hansen, James E.
What Global Warming Looks Like The July 2010 global map of surface temperature anomalies (Figure 1 anomalies an example of what we can expect global warming to look like? Maps of temperature anomalies, such as Figure 1, are useful for helping people understand the role of global warming in extreme events
Thomas Wiegelmann; Bernd Inhester
2006-12-21
The space mission STEREO will provide images from two viewpoints. An important aim of the STEREO mission is to get a 3D view of the solar corona. We develop a program for the stereoscopic reconstruction of 3D coronal loops from images taken with the two STEREO spacecraft. A pure geometric triangulation of coronal features leads to ambiguities because the dilute plasma emissions complicates the association of features in image 1 with features in image 2. As a consequence of these problems the stereoscopic reconstruction is not unique and multiple solutions occur. We demonstrate how these ambiguities can be resolved with the help of different coronal magnetic field models (potential, linear and non-linear force-free fields). The idea is that, due to the high conductivity in the coronal plasma, the emitting plasma outlines the magnetic field lines. Consequently the 3D coronal magnetic field provides a proxy for the stereoscopy which allows to eliminate inconsistent configurations. The combination of stereoscopy and magnetic modelling is more powerful than one of these tools alone. We test our method with the help of a model active region and plan to apply it to the solar case as soon as STEREO data become available.
New Magnetic confirguration in paramagnetic phase of HoCo2
Bonilla, C.M.; Calvo, I.; Herrero-Albillos, J.; Figueroa, A.I.; Castan-Guerrero, C.; Bertolome, J.; Rodriguez-Velamazan, J.A.; Schmitz, D.; Weschke, E.; Paudyal, Durga; Pecharsky, Vitalij; Gschneidner Jr, Karl; Bartolome, F.; Garcia, D.
2012-02-23
X-ray magnetic circular dichroism (XMCD) measurements on HoCo2 reveal the inversion of Co moment at temperatures higher than the critical temperature, Tc, showing that the net magnetization under a field of the Ho and Co sublattices remain antiparallel even above Tc. The Ho moment also changes its orientation to align antiparallel to the applied field at high temperature giving rise to a new magnetic configuration in the paramagnetic regime. Transverse susceptibility (TS) and small angle neutron scattering (SANS) measurements performed above Tc indicate the existence of sizable magnetic short-range correlated regions in HoCo2. First principles calculations based on spin polarized local-density approximation, LSDA+U havebeen performed to obtain insights on the origin of the short-range correlated volume.
Relating the Newman-Penrose constants to the Geroch-Hansen multipole moments
Thomas Bäckdahl
2009-08-25
In this paper, we express the Newman--Penrose constants in terms of the Geroch--Hansen multipole moments for stationary spacetimes. These expressions are translation-invariant combinations of the multipole moments up to quadrupole order, which do not normally vanish.
MOMENTS OF THE TRANSMISSION EIGENVALUES, PROPER DELAY TIMES AND RANDOM MATRIX THEORY I
Mezzadri, Francesco
to the moments of the transmission eigenvalues of the electric current through a ballistic cavity; the negativeMOMENTS OF THE TRANSMISSION EIGENVALUES, PROPER DELAY TIMES AND RANDOM MATRIX THEORY I F. MEZZADRI of the transmission eigenvalues of an electron through a quantum dot with chaotic dynamics. For the Laguerre ensemble
Impact of Friction and Scale-Dependent Initial Stress on Radiated Energy-Moment Scaling
Shaw, Bruce E.
. Shaw LamontDoherty Earth Observatory, Columbia University, New York, USA The radiated energy coming271 Impact of Friction and Scale-Dependent Initial Stress on Radiated Energy-Moment Scaling Bruce E of elucidat- ing their radiated energy-moment scaling. We find, contrary to expectations, that apparent stress
Jefferson Lab's results on the Q^2-evolution of moments of spin structure functions
A. Deur
2005-07-15
We present the recent JLab measurements on moments of spin structure functions at intermediate and low Q^2. The Bjorken sum and Burkhardt-Cottingham sum on the neutron are presented. The later appears to hold. Higher moments (generalized spin polarizabilities and d_2^n) are shown and compared to chiral perturbation theory and lattice QCD respectively.
LOCKING-FREE FINITE ELEMENT METHOD FOR A BENDING MOMENT FORMULATION OF TIMOSHENKO BEAMS
RodrÃguez, Rodolfo
LOCKING-FREE FINITE ELEMENT METHOD FOR A BENDING MOMENT FORMULATION OF TIMOSHENKO BEAMS FELIPE LEPE, DAVID MORA, AND RODOLFO RODRÂ´IGUEZ Abstract. In this paper we study a finite element formulation of the transverse displacement, rota- tion, shear stress and bending moment. By using the classical Babuska
FINITE ELEMENT ANALYSIS OF A BENDING MOMENT FORMULATION FOR THE VIBRATION PROBLEM OF A
RodrÃguez, Rodolfo
FINITE ELEMENT ANALYSIS OF A BENDING MOMENT FORMULATION FOR THE VIBRATION PROBLEM OF A NON-HOMOGENEOUS TIMOSHENKO BEAM FELIPE LEPE, DAVID MORA, AND RODOLFO RODRÂ´IGUEZ Abstract. In this paper we analyze a low-homogeneous Timoshenko beam. We consider a formulation in which the bending moment is introduced as an additional unknown
SEISMIC PERFORMANCE EVALUATION FOR STEEL MOMENT FRAMES By Seung-Yul Yun1
Sweetman, Bert
SEISMIC PERFORMANCE EVALUATION FOR STEEL MOMENT FRAMES By Seung-Yul Yun1 , Ronald O. Hamburger2 , C than existing buildings designed and built with older technologies. Key words: seismic behavior; seismic performance evaluation; performance-based design; earthquake engineering; steel moment frame
Role of fourth-order phase-space moments in collective modes of trapped Fermi gases
Chiacchiera, Silvia; Lepers, Thomas; Davesne, Dany; Urban, Michael
2011-10-15
We study the transition from hydrodynamic to collisionless behavior in collective modes of ultracold trapped Fermi gases. To that end, we solve the Boltzmann equation for the trapped Fermi gas via the moments method. We showed previously that it is necessary to go beyond second-order moments if one wants to reproduce the results of a numerical solution of the Boltzmann equation. Here, we will give the detailed description of the method including fourth-order moments. We apply this method to the case of realistic parameters, and compare the results for the radial quadrupole and scissors modes at unitarity to experimental data obtained by the Innsbruck group. It turns out that the inclusion of fourth-order moments clearly improves the agreement with the experimental data. In particular, the fourth-order moments reduce the effect of collisions and therefore partially compensate the effect of the enhanced in-medium cross section at low temperatures.
Deconfinement to quark matter in neutron stars - The influence of strong magnetic fields
Dexheimer, V.; Negreiros, R.; Schramm, S.; Hempel, M.
2013-03-25
We use an extended version of the hadronic SU(3) non-linear realization of the sigma model that also includes quarks to study hybrid stars. Within this approach, the degrees of freedom change naturally as the temperature/density increases. Different prescriptions of charge neutrality, local and global, are tested and the influence of strong magnetic fields and the anomalous magnetic moment on the particle population is discussed.
Simulating net particle production and chiral magnetic current in a CP-odd domain
Fukushima, Kenji
2015-01-01
We elucidate the numerical formulation to simulate net production of particles and anomalous currents with CP-breaking background fields which cause an imbalance of particles over anti-particles. For a concrete demonstration we numerically impose pulsed electric and magnetic fields to observe that the dynamical chiral magnetic current follows together with the net particle production. The produced particle density is quantitatively consistent with the axial anomaly, while the chiral magnetic current is suppressed by a delay before the the onset of the current generation.
Detection of pico-Tesla magnetic fields using magneto-electric sensors at room temperature
Zhai Junyi; Xing Zengping; Dong Shuxiang; Li Jiefang; Viehland, D. [Department of Materials Science and Engineering, Virginia Tech, Blacksburg, Virginia 24061 (United States)
2006-02-06
The measurement of low-frequency (10{sup -2}-10{sup 3} Hz) minute magnetic field variations (10{sup -12} Tesla) at room temperature in a passive mode of operation would be critically enabling for deployable neurological signal interfacing and magnetic anomaly detection applications. However, there is presently no magnetic field sensor capable of meeting all of these requirements. Here, we present new bimorph and push-pull magneto-electric laminate composites, which incorporate a charge compensation mechanism (or bridge) that dramatically enhances noise rejection, enabling achievement of such requirements.
Nuclear Electric Dipole Moments in Chiral Effective Field Theory
J. Bsaisou; J. de Vries; C. Hanhart; S. Liebig; Ulf-G. Meißner; D. Minossi; A. Nogga; A. Wirzba
2015-04-30
We provide a consistent and complete calculation of the electric dipole moments of the deuteron, helion, and triton in the framework of chiral effective field theory. The CP-conserving and CP-violating interactions are treated on equal footing and we consider CP-violating one-, two-, and three-nucleon operators up to next-to-leading-order in the chiral power counting. In particular, we calculate for the first time EDM contributions induced by the CP-violating three-pion operator. We find that effects of CP-violating nucleon-nucleon contact interactions are larger than those found in previous studies based on phenomenological models for the CP-conserving nucleon-nucleon interactions. Our results which apply to any model of CP violation in the hadronic sector can be used to test various scenarios of CP violation. As examples, we study the implications of our results on the QCD $\\theta$-term and the minimal left-right symmetric model.
Neutron Electric Dipole Moment and Tensor Charges from Lattice QCD
Tanmoy Bhattacharya; Vincenzo Cirigliano; Rajan Gupta; Huey-Wen Lin; Boram Yoon
2015-07-06
We present Lattice QCD results on the neutron tensor charges including, for the first time, a simultaneous extrapolation in the lattice spacing, volume, and light quark masses to the physical point in the continuum limit. We find that the "disconnected" contribution is smaller than the statistical error in the "connected" contribution. Our estimates in the $\\overline{\\text{MS}}$ scheme at $2$ GeV, including all systematics, are $g_T^{d-u}=1.020(76)$, $g_T^d = 0.774(66)$, $g_T^u = - 0.233(28)$, and $g_T^s = 0.008(9)$. The flavor diagonal charges determine the size of the neutron electric dipole moment (EDM) induced by quark EDMs that are generated in many new scenarios of CP-violation beyond the Standard Model (BSM). We use our results to derive model-independent bounds on the EDMs of light quarks and update the EDM phenomenology in split Supersymmetry with gaugino mass unification, finding a stringent upper bound of $d_n neutron EDM in this scenario.
Tomislav Ivezic
2010-05-17
In a recent paper [A. O. Sushkov, S. Eckel and S. K. Lamoreaux, Phys. Rev. A 79, 022118 (2009), arXiv:0810.2756 ] the authors measured the EDM-induced magnetization M that is given by Eq. (1) in their paper. Such an expression for M is a consequence of the generally accepted opinion that both dipole moments, a MDM m and an EDM d, are proportional to the spin S. Recently [T. Ivezic, Phys. Scr. 81, 025001 (2010)] the Uhlenbeck-Goudsmit hypothesis is generalized in a Lorentz covariant manner using the four-dimensional (4D) geometric quantities. From the viewpoint of such formulation there is no EDM-induced magnetization M; in the 4D spacetime the EDM d^{a} is not proportional to S^{a}. It is argued that the induced M can come from the direct interaction between the applied electric field E^{a} and a MDM m^{a}.
SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) 2013
Gordon Rueff; Lyle Roybal; Denis Vollmer
2013-01-01
There is a significant need to protect the nation’s energy infrastructures from malicious actors using cyber methods. Supervisory, Control, and Data Acquisition (SCADA) systems may be vulnerable due to the insufficient security implemented during the design and deployment of these control systems. This is particularly true in older legacy SCADA systems that are still commonly in use. The purpose of INL’s research on the SCADA Protocol Anomaly Detection Utilizing Compression (SPADUC) project was to determine if and how data compression techniques could be used to identify and protect SCADA systems from cyber attacks. Initially, the concept was centered on how to train a compression algorithm to recognize normal control system traffic versus hostile network traffic. Because large portions of the TCP/IP message traffic (called packets) are repetitive, the concept of using compression techniques to differentiate “non-normal” traffic was proposed. In this manner, malicious SCADA traffic could be identified at the packet level prior to completing its payload. Previous research has shown that SCADA network traffic has traits desirable for compression analysis. This work investigated three different approaches to identify malicious SCADA network traffic using compression techniques. The preliminary analyses and results presented herein are clearly able to differentiate normal from malicious network traffic at the packet level at a very high confidence level for the conditions tested. Additionally, the master dictionary approach used in this research appears to initially provide a meaningful way to categorize and compare packets within a communication channel.
Large scale CMB anomalies from thawing cosmic strings
Christophe Ringeval; Daisuke Yamauchi; Jun'ichi Yokoyama; Francois R. Bouchet
2015-10-07
Cosmic strings formed during inflation are expected to be either diluted over super-Hubble distances, i.e., invisible today, or to have crossed our past light cone very recently. We discuss the latter situation in which a few strings imprint their signature in the Cosmic Microwave Background (CMB) Anisotropies after recombination. Being almost frozen in the Hubble flow, these strings are quasi static and evade almost all of the previously derived constraints on their tension while being able to source large scale anisotropies in the CMB sky. Using a local variance estimator on thousand of numerically simulated Nambu-Goto all sky maps, we compute the expected signal and show that it can mimic a dipole modulation at large angular scales while being negligible at small angles. Interestingly, such a scenario generically produces one cold spot from the thawing of a cosmic string loop. Mixed with anisotropies of inflationary origin, we find that a few strings of tension GU = O(1) x 10^(-6) match the amplitude of the dipole modulation reported in the Planck satellite measurements and could be at the origin of other large scale anomalies.
Klokkenburg, M.; Erne, B. H.; Petukhov, A. V.; Philipse, A. P. [Van 't Hoff Laboratory for Physical and Colloid Chemistry, Debye Institute, Utrecht University, Padualaan 8, 3584 CH Utrecht (Netherlands); Wiedenmann, A. [Hahn-Meitner-Institut Berlin, Department SF3, Glienickerstrasse 100, D-14109 Berlin (Germany)
2007-05-15
Field-induced structure formation in a ferrofluid with well-defined magnetite nanoparticles with a permanent magnetic dipole moment was studied with small-angle neutron scattering (SANS) as a function of the magnetic interactions. The interactions were tuned by adjusting the size of the well-defined, single-magnetic-domain magnetite (Fe{sub 3}O{sub 4}) particles and by applying an external magnetic field. For decreasing particle dipole moments, the data show a progressive distortion of the hexagonal symmetry, resulting from the formation of magnetic sheets. The SANS data show qualitative agreement with recent cryogenic transmission electron microscopy results obtained in 2D [Klokkenburg et al., Phys. Rev. Lett. 97, 185702 (2006)] on the same ferrofluids.
RECENT MAGNETIC STRUCTURE STUDIES BY NEUTRON DIFFRACTION(1) By C. G. SHULL,
Boyer, Edmond
classification by neutron scattering include the determination of the magnitude and quality of an atom of this moment as represented in the form factor for neutron scattering. Within the second classification169 RECENT MAGNETIC STRUCTURE STUDIES BY NEUTRON DIFFRACTION(1) By C. G. SHULL, Massachusetts
Observation of Half-Height Magnetization Steps in Sr2RuO4
Goldbart, Paul M.
of the magnetic moment of a conventional, full-quantum vortex (FQV), for which Dq ¼ Dq ¼ T2p. The Meissner with the entry of single vor- tices. To facilitate this aim, we have fabricated annular samples by drilling, but evades complications arising from the vortex core. For an annular conventional superconductor
Version 2.0 Finite nuclear mass corrections to electric and magnetic
Pachucki, Krzysztof
for the leading corrections to the relativistic contribution to energy, the transition electric dipole moment to rovibrational energies in diatomic molecules. 2 #12; Further examples are finite nuclear mass correctionsVersion 2.0 Finite nuclear mass corrections to electric and magnetic interactions in diatomic
Masaaki Yamada, Russell Kulsrud and Hantao Ji
2009-09-17
We review the fundamental physics of magnetic reconnection in laboratory and space plasmas, by discussing results from theory, numerical simulations, observations from space satellites, and the recent results from laboratory plasma experiments. After a brief review of the well-known early work, we discuss representative recent experimental and theoretical work and attempt to interpret the essence of significant modern findings. In the area of local reconnection physics, many significant findings have been made with regard to two- uid physics and are related to the cause of fast reconnection. Profiles of the neutral sheet, Hall currents, and the effects of guide field, collisions, and micro-turbulence are discussed to understand the fundamental processes in a local reconnection layer both in space and laboratory plasmas. While the understanding of the global reconnection dynamics is less developed, notable findings have been made on this issue through detailed documentation of magnetic self-organization phenomena in fusion plasmas. Application of magnetic reconnection physics to astrophysical plasmas is also brie y discussed.
Patterned Magnetic Nanostructures and Quantized Magnetic Disks
-increasing demands in data storage and to new applications of magnetic devices in the field of sensors. NewPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper, opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra
General classical and quantum-mechanical description of magnetic resonance
Alexander J. Silenko
2015-08-04
A general theoretical description of the magnetic resonance is given. General formulas describing a behavior of all components of the polarization vector at the magnetic resonance are derived in the case of an arbitrary initial polarization. The equations obtained are exact on condition that the nonresonance rotating field is neglected. The spin dynamics is also calculated at frequencies far from resonance without neglecting the above-mentioned field. A quantum-mechanical analysis of the spin evolution at the magnetic resonance is fulfilled and the full agreement between the classical and quantum-mechanical approaches is proven. Distinguishing features of magnetic and quasimagnetic resonances for nuclei and particles moving in accelerators and storage rings which include resonances caused by the electric dipole moment are considered.
General classical and quantum-mechanical description of magnetic resonance
Silenko, Alexander J
2015-01-01
A general theoretical description of the magnetic resonance is given. General formulas describing a behavior of all components of the polarization vector at the magnetic resonance are derived in the case of an arbitrary initial polarization. The equations obtained are exact on condition that the nonresonance rotating field is neglected. The spin dynamics is also calculated at frequencies far from resonance without neglecting the above-mentioned field. A quantum-mechanical analysis of the spin evolution at the magnetic resonance is fulfilled and the full agreement between the classical and quantum-mechanical approaches is proven. Distinguishing features of magnetic and quasimagnetic resonances for nuclei and particles moving in accelerators and storage rings which include resonances caused by the electric dipole moment are considered.
Basin Research (1999) 11, 285290 Gravity anomalies, subsidence history and the tectonic
Watts, A. B. "Tony"
1999-01-01
Basin Research (1999) 11, 285290 DISCUSSION Gravity anomalies, subsidence history and the tectonic' (Madon &and calculate the stretching factor (b), Madon & Watts (1998) conducted subsidence time were then matched to best-fit DEPOSITIONAL ENVIRONMENTS ANDtheoretical subsidence curves
Z' Bosons, the NuTeV Anomaly, and the Higgs Boson Mass
Chanowitz, Michael S
2009-01-01
NuTeV Anomaly, and the Higgs Boson Mass Michael S. Chanowitzpredicted value of the Higgs boson mass, from ? 60 to ? 120from an increase in the Higgs boson mass. There is a vast
Empirical vertical structure of density anomaly in the Gulf of Mexico
Current, Carole Louise
1993-01-01
Climatological vertical structure of density anomaly in the Gulf of Mexico is realistically characterized in a form useful for calibration and/or verification of numerical circulation models, employing a new method that ...
Anomalies in the theory of viscous energy losses due to shear...
Office of Scientific and Technical Information (OSTI)
resonators. Citation Details In-Document Search Title: Anomalies in the theory of viscous energy losses due to shear in rotational MEMS resonators. In this paper, the effect of...
Self-energy anomaly of an electric pointlike dipole in three-dimensional static spacetimes
Valeri P. Frolov; Andrey A. Shoom; Andrei Zelnikov
2013-03-07
We calculate the self-energy anomaly of a pointlike electric dipole located in a static $(2+1)$-dimensional curved spacetime. The energy functional for this problem is invariant under an infinite-dimensional (gauge) group of transformations parameterized by one scalar function of two variables. We demonstrate that the problem of the calculation of the self-energy anomaly for a pointlike dipole can be reduced to the calculation of quantum fluctuations of an effective two-dimensional Euclidean quantum field theory. We reduced the problem in question to the calculation of the conformal anomaly of an effective scalar field in two dimensions and obtained an explicit expression for the self-energy anomaly of an electric dipole in an asymptotically flat, regular $(2+1)$-dimensional spacetime which may have electrically neutral black-hole-like metrics with regular Killing horizon.
BEC-BCS crossover driven by the axial anomaly in the NJL model
Abuki, Hiroaki; Hatsuda, Tetsuo; Yamamoto, Naoki
2010-01-01
We study the QCD phase structure in the three-flavor Nambu--Jona-Lasinio model, incorporating the chiral-diquark interplay due to the axial anomaly. We demonstrate that for a certain range of model parameters, the low temperature critical point predicted by a Ginzburg-Landau analysis appears in the phase diagram. In addition, we show that the axial anomaly presents a new scenario for a possible BEC-BCS crossover in the color-flavor locked phase of QCD.
Hubrig, S; Ilyin, I; Korhonen, H; Schoeller, M; Savanov, I; Arlt, R; Castelli, F; Curto, G Lo; Briquet, M; Dall, T H
2012-01-01
The frequent presence of weak magnetic fields on the surface of spotted late-B stars with HgMn peculiarity in binary systems has been controversial during the two last decades. We re-analyse available spectropolarimetric material by applying the moment technique on spectral lines of inhomogeneously distributed elements separately. Furthermore, we present new determinations of the mean longitudinal magnetic field for the HgMn star HD65949 and the hotter analog of HgMn stars, the PGa star HD19400, using FORS2 installed at the VLT. We also give new measurements of the eclipsing system AR Aur with a primary star of HgMn peculiarity which were obtained with the SOFIN spectropolarimeter installed at the Nordic Optical Telescope. We downloaded from the ESO archive the publically available HARPS spectra for eight HgMn stars and one normal and one superficially normal B-type star obtained in 2010. The application of the moment technique to the HARPS and SOFIN spectra allowed us to study the presence of the longitudina...
Peskin, Victor; Boduszynski, Mieczyslaw P.
2003-01-01
visits atrocity sights in Croatia,” Deutsche Presse-Agentur,of California, Berkeley Croatia’s Moments of Truth: Thesocrates.berkeley.edu/~bsp/ Croatia’s Moments of Truth: The
Addressing the Challenges of Anomaly Detection for Cyber Physical Energy Grid Systems
Ferragut, Erik M; Laska, Jason A; Melin, Alexander M; Czejdo, Bogdan
2013-01-01
The consolidation of cyber communications networks and physical control systems within the energy smart grid introduces a number of new risks. Unfortunately, these risks are largely unknown and poorly understood, yet include very high impact losses from attack and component failures. One important aspect of risk management is the detection of anomalies and changes. However, anomaly detection within cyber security remains a difficult, open problem, with special challenges in dealing with false alert rates and heterogeneous data. Furthermore, the integration of cyber and physical dynamics is often intractable. And, because of their broad scope, energy grid cyber-physical systems must be analyzed at multiple scales, from individual components, up to network level dynamics. We describe an improved approach to anomaly detection that combines three important aspects. First, system dynamics are modeled using a reduced order model for greater computational tractability. Second, a probabilistic and principled approach to anomaly detection is adopted that allows for regulation of false alerts and comparison of anomalies across heterogeneous data sources. Third, a hierarchy of aggregations are constructed to support interactive and automated analyses of anomalies at multiple scales.
Fourth Moment Theorem and q-Brownian Chaos Aurelien Deya1, Salim Noreddine2 and Ivan Nourdin3
Paris-Sud XI, Université de
Fourth Moment Theorem and q-Brownian Chaos Aur´elien Deya1, Salim Noreddine2 and Ivan Nourdin3 Abstract: In 2005, Nualart and Peccati [12] showed the so-called Fourth Moment Theorem asserting that, it is necessary and sufficient that its fourth moment tends to 3. A few years later, Kemp et al. [8] extended
Ramp-rate sensitivity of SSC dipole magnet prototypes
Devred, A.; Ogitsu, T.
1994-07-01
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.
Effect of attractive interactions on the water-like anomalies of a core-softened model potential
Pant, Shashank; Gera, Tarun; Choudhury, Niharendu E-mail: niharc2002@yahoo.com
2013-12-28
It is now well established that water-like anomalies can be reproduced by a spherically symmetric potential with two length scales, popularly known as core-softened potential. In the present study we aim to investigate the effect of attractive interactions among the particles in a model fluid interacting with core-softened potential on the existence and location of various water-like anomalies in the temperature-pressure plane. We employ extensive molecular dynamic simulations to study anomalous nature of various order parameters and properties under isothermal compression. Order map analyses have also been done for all the potentials. We observe that all the systems with varying depth of attractive wells show structural, dynamic, and thermodynamic anomalies. As many of the previous studies involving model water and a class of core softened potentials have concluded that the structural anomaly region encloses the diffusion anomaly region, which in turn, encloses the density anomaly region, the same pattern has also been observed in the present study for the systems with less depth of attractive well. For the systems with deeper attractive well, we observe that the diffusion anomaly region shifts toward higher densities and is not always enclosed by the structural anomaly region. Also, density anomaly region is not completely enclosed by diffusion anomaly region in this case.
Superconducting Magnet Division
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
Satti, John A. (Naperville, IL)
1980-01-01
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.
Basics and prospective of magnetic Heusler compounds
Felser, Claudia Wollmann, Lukas; Chadov, Stanislav; Fecher, Gerhard H.; Parkin, Stuart S. P.
2015-04-01
Heusler compounds are a remarkable class of materials with more than 1000 members and a wide range of extraordinary multi-functionalities including halfmetallic high-temperature ferri- and ferromagnets, multi-ferroics, shape memory alloys, and tunable topological insulators with a high potential for spintronics, energy technologies, and magneto-caloric applications. The tunability of this class of materials is exceptional and nearly every functionality can be designed. Co{sub 2}-Heusler compounds show high spin polarization in tunnel junction devices and spin-resolved photoemission. Manganese-rich Heusler compounds attract much interest in the context of spin transfer torque, spin Hall effect, and rare earth free hard magnets. Most Mn{sub 2}-Heusler compounds crystallize in the inverse structure and are characterized by antiparallel coupling of magnetic moments on Mn atoms; the ferrimagnetic order and the lack of inversion symmetry lead to the emergence of new properties that are absent in ferromagnetic centrosymmetric Heusler structures, such as non-collinear magnetism, topological Hall effect, and skyrmions. Tetragonal Heusler compounds with large magneto crystalline anisotropy can be easily designed by positioning the Fermi energy at the van Hove singularity in one of the spin channels. Here, we give a comprehensive overview and a prospective on the magnetic properties of Heusler materials.
Comparative Visualization of Two-Dimensional Flow Data Using Moment Invariants
Hamann, Bernd
Comparative Visualization of Two-Dimensional Flow Data Using Moment Invariants author1, author2 affiliation1 affiliation2 Email: {author1,author2}@affiliation Abstract The analysis of time-dependent data
Search for the electric dipole moment of the electron with thorium monoxide
2010-01-01
moment of the electron with thorium monoxide A C Vutha, W Cmoment of the electron with thorium monoxide A C Vutha 1 , WeEDM, using a cold beam of thorium monoxide (ThO) molecules.
Curvature of a cantilever beam subjected to an equi-biaxial bending moment
Krulevitch, P.; Johnson, G.C.
1998-04-28
Results from a finite element analysis of a cantilever beam subjected to an equi-biaxial bending moment demonstrate that the biaxial modulus E/(I-v) must be used even for narrow beams.
Use of a moments method for the analysis of flux distributions in subcritical assemblies
Cheng, Hsiang-Shou
1968-01-01
A moments method has been developed for the analysis of flux distributions in subcritical neutron-multiplying assemblies. The method determines values of the asymptotic axial and radial buckling, and of the extrapolated ...
Structures and magnetic properties of Co-Zr-B magnets studied by first-principles calculations
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhao, Xin; Ke, Liqin; Nguyen, Manh Cuong; Wang, Cai-Zhuang; Ho, Kai-Ming
2015-06-23
The structures and magnetic properties of Co-Zr-B alloys near the composition of Co5Zr with B at. % ?6% were studied using adaptive genetic algorithm and first-principles calculations. The energy and magnetic moment contour maps as a function of chemical composition were constructed for the Co-Zr-B magnet alloys through extensive structure searches and calculations. We found that Co-Zr-B system exhibits the same structure motif as the “Co11Zr2”polymorphs, and such motif plays a key role in achieving strong magnetic anisotropy. Boronatoms were found to be able to substitute cobalt atoms or occupy the “interruption” sites. First-principles calculations showed that the magnetocrystalline anisotropymore »energies of the boron-doped alloys are close to that of the high-temperature rhombohedral Co5Zr phase and larger than that of the low-temperature Co5.25Zr phase. Our calculations provide useful guidelines for further experimental optimization of the magnetic performances of these alloys.« less
Characterization and Simulation of Transient Vibrations Using Band Limited Temporal Moments
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Smallwood, David O.
1994-01-01
A method is described to characterize shocks (transient time histories) in terms of the Fourier energy spectrum and the temporal moments of the shock passed through a contiguous set of band pass filters. The product model is then used to generate of a random process as simulations that in the mean will have the same energy and moments as the characterization of the transient event.
Quark-hadron duality and truncated moments of nucleon structure functions
Psaker, A. [Jefferson Laboratory, Newport News, Virginia 23606 (United States); Hampton University, Hampton, Virginia 23668 (United States); American University of Nigeria, Yola (Nigeria); Melnitchouk, W. [Jefferson Laboratory, Newport News, Virginia 23606 (United States); Christy, M. E. [Hampton University, Hampton, Virginia 23668 (United States); Keppel, C. [Jefferson Laboratory, Newport News, Virginia 23606 (United States); Hampton University, Hampton, Virginia 23668 (United States)
2008-08-15
We employ a novel new approach to study local quark-hadron duality using 'truncated' moments, or integrals of structure functions over restricted regions of x, to determine the degree to which individual resonance regions are dominated by leading twist. Because truncated moments obey the same Q{sup 2} evolution equations as the leading twist parton distributions, this approach makes possible for the first time a description of resonance region data and the phenomenon of quark-hadron duality directly from QCD.
Nanostructured magnetic materials
Chan, Keith T.
2011-01-01
Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface
Enhanced Magnetism of Fe3O4 Nanoparticles with Ga Doping
Pool, V. L.; Klem, M. T.; Chorney, C. L.; Arenholz, E.; Idzerda, Y.U.
2010-10-22
Magnetic (Ga{sub x}Fe{sub 1-x}){sub 3}O{sub 4} nanoparticles with 5%-33% gallium doping (x = 0.05-0.33) were measured using x-ray absorption spectroscopy and x-ray magnetic circular dichroism to determine that the Ga dopant is substituting for Fe{sub 3+} as Ga{sub 3+} in the tetrahedral A-site of the spinel structure, resulting in an overall increase in the total moment of the material. Frequency-dependent alternating-current magnetic susceptibility measurements showed these particles to be weakly interacting with a reduction of the cubic anisotropy energy term with Ga concentration. The element-specific dichroism spectra show that the average Fe moment is observed to increase with Ga concentration, a result consistent with the replacement of A-site Fe by Ga.
Electronic structural and magnetic properties of Mn{sub 5}Ge{sub 3} clusters
Yuan, H. K.; Chen, H. Kuang, A. L.; Tian, C. L.; Wang, J. Z.
2013-11-28
Theoretical understanding of the stability, ferromagnetism, and spin polarization of Mn{sub 5}Ge{sub 3} clusters has been performed by using the density functional theory with generalized gradient approximation for exchange and correlation. The magnetic moments and magnetic anisotropy energy (MAE) have been calculated for both bulk and clusters, and the enhanced magnetic moment as well as the enlarged MAE have been identified in clusters. The most attractive achievement is that Mn{sub 5}Ge{sub 3} clusters show a fine half-metallic character with large energy scales. The present results may have important implications for potential applications of small Mn{sub 5}Ge{sub 3} clusters as both emerging spintronics and next-generation data-storage technologies.
A High-Order Finite-Volume Algorithm for Fokker-Planck Collisions in Magnetized Plasmas
Xiong, Z; Cohen, R H; Rognlien, T D; Xu, X Q
2007-04-18
A high-order finite volume algorithm is developed for the Fokker-Planck Operator (FPO) describing Coulomb collisions in strongly magnetized plasmas. The algorithm is based on a general fourth-order reconstruction scheme for an unstructured grid in the velocity space spanned by parallel velocity and magnetic moment. The method provides density conservation and high-order-accurate evaluation of the FPO independent of the choice of the velocity coordinates. As an example, a linearized FPO in constant-of-motion coordinates, i.e. the total energy and the magnetic moment, is developed using the present algorithm combined with a cut-cell merging procedure. Numerical tests include the Spitzer thermalization problem and the return to isotropy for distributions initialized with velocity space loss cones. Utilization of the method for a nonlinear FPO is straightforward but requires evaluation of the Rosenbluth potentials.
Experimental estimation of dynamic plastic bending moments by plastic hinge models
Sogo, T.; Ujihashi, S.; Matsumoto, H.; Adachi, T.
1995-12-31
In the present paper, the experimental estimation of dynamic plastic bending moments for metallic materials is investigated. The three-point bending, test under impact and static loads is applied to aluminum alloy (JIS A6063S) and mild steel (JIS SS400). It is confirmed that tile dynamic bending deformations in three-point bending test can be modeled as a plastic hinge, tile experimental results show that the consumed energies of the specimens are proportional to the bending angles. The ratio of the consumed energy to the bending angle is approximately equal to the plastic bending moment. In the case of aluminum alloy, the dynamic plastic bending moments for the different average bending angular velocities coincide with the static plastic bending moments. On the other hand, in the case of mild steel, the dynamic plastic bending moments are proportional to the average bending angular velocities. As a result, we confirm that the present method based on the plastic hinge model and the consumed energy is efficient for determining tile dynamic plastic bending moment.
Multipole moments of water molecules in clusters and ice Ih from first principles calculations
Batista, E.R. [Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195-1560 (United States)] [Department of Physics, Box 351560, University of Washington, Seattle, Washington 98195-1560 (United States); [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States); Xantheas, S.S. [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 906 Battelle Boulevard, PO Box 999, MS K8-91, Richland, Washington 99352 (United States)] [Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, 906 Battelle Boulevard, PO Box 999, MS K8-91, Richland, Washington 99352 (United States); Jonsson, H. [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States)] [Department of Chemistry, Box 351700, University of Washington, Seattle, Washington 98195-1700 (United States)
1999-10-01
We have calculated {ital molecular} multipole moments for water molecules in clusters and in ice Ih by partitioning the charge density obtained from first principles calculations. Various schemes for dividing the electronic charge density among the water molecules were used. They include Bader{close_quote}s zero flux surfaces and Voronoi partitioning schemes. A comparison was also made with an induction model including dipole, dipole-quadrupole, quadrupole-quadrupole polarizability and first hyperpolarizability as well as fixed octopole and hexadecapole moments. We have found that the different density partitioning schemes lead to widely different values for the molecular multipoles, illustrating how poorly defined molecular multipoles are in clusters and condensed environments. For instance, the magnitude of the molecular dipole moment in ice Ih ranges between 2.3 D and 3.1 D depending on the partitioning scheme used. Within each scheme, though, the value for the molecular dipole moment in ice is larger than in the hexamer. The magnitude of the molecular dipole moment in the clusters shows a monotonic increase from the gas phase value to the one in ice Ih, with the molecular dipole moment in the water ring hexamer being smaller than the one in ice Ih for all the partitioning schemes used. {copyright} {ital 1999 American Institute of Physics.}
Casadei, Cecilia
2012-05-09
The aim of the present thesis is to investigate the local magnetic properties of homometallic Cr{sub 8} antiferromagnetic (AFM) ring and the changes occurring by replacing one Cr{sup 3+} ion with diamagnetic Cd{sup 2+} (Cr{sub 7}Cd) and with Ni{sup 2+} (Cr{sub 7}Ni). In the heterometallic ring a redistribution of the local magnetic moment is expected in the low temperature ground state. We have investigated those changes by both {sup 53}Cr-NMR and {sup 19}F-NMR. We have determined the order of magnitude of the transferred hyperfine coupling constant {sup 19}F - M{sup +} where M{sup +} = Cr{sup 3+}, Ni{sup 2+} in the different rings. This latter result gives useful information about the overlapping of the electronic wavefunctions involved in the coordinative bond.
Magnetism in Non-Traditional Materials
Menon, Madhu
2013-09-17
We performed a systematic microscopic investigation of two completely dissimilar materials (namely, ZnO and rhombohedral-C{sub 60} polymers) exhibiting ferromagnetism in the presence of defects, and showed that this new phenomena has a common origin and the mechanism responsible can be used as a powerful tool for inducing and tailoring magnetic features in systems which are not magnetic otherwise. Based on our findings we proposed a general recipe for developing ferromagnetism in new materials of great technological interest. Our results support the role of complimentary pairs of defects in inducing magnetism in otherwise non-magnetic materials belonging to two widely differing classes with no apparent correlation between them. In both classes, ferromagnetism is found to be enhanced when the two kinds of defects form structures (pathways) of alternating effective donor and acceptor crystal sites leading to the development of electron charge and spin density like waves. Using ab initio density functional theory calculations we predicted the existence of a new class of carbon cages formed via hybrid connection between planar graphene sheets and carbon nanotubes. The resulting novel structure has the appearance of ?nano-drum? and offers the exciting prospect of integrating useful device properties of both graphene as well as the nanotube into a single unit with tunable electronic properties. Creation of a hexagonal hole in the graphene portion of this structure results in significant magnetic moments for the edge atoms. The structure appears to be capable of sustaining ferrimagnetic state with the assistance of topological defects. The charge and spin distributions obtained in our calculations for the nano-drums are in striking contrast to those in planar graphene nanoribbons with a central hole. In this case, the central hole appears as the complimentary defect to those of the ribbon edges. Similar situation is found in case of the nano-drum in which the complimentary to the hole defects appear to be the pentagons along the curved surface of the drum. Charge oscillations found in the nano-drum are minimized in the nanoribbons. But more importantly, the hole edge atoms in the nano-drums retain significant magnetic moments; almost twice those of the corresponding ones in hydrogenated graphene nanoribbons (H-GNRs). These results suggest that the topological defects in the nano-drums may act like blocks to keep magnetic moments from ?leaking? out from the hole defects. This may have significant implications for the the use of nano-drums in magnetic storage technology where the ratio, magnetic-moment/weight, is of paramount importance in any futuristic device applications. One of the basic problems of the DFT/LSDA+U theory is the efficient evaluation of the U-term. With this in mind we proposed an alternative approach for its calculation which is based on the knowledge of the Hartree-Fock wave functions of the system under consideration. As a result, the proposed approach is closer to the basic definition of the DFT/LSDA+U scheme and its hybrid-DFT nature. According to our approach, the U value is obtained in a consistent and ab-initio way using the self-consistently calculated wave functions of the given system at the level of the HF approximation. Our method is applicable for systems which include more than one type of elements with localized d-orbitals. The method has been applied the case of the doped Zn(Co)O systems successfully. Currently, theories based on conventional superexchange or double-exchange interactions cannot explain long range magnetic order at concentrations below percolation threshold in dilute magnetic semiconductors. On the other hand, the codoping induced magnetism, which can justify magnetic interactions below percolation threshold, has eluded explanation. With this in mind, we proposed that defect-induced magnetism in codoped non-magnetic materials can be viewed within a molecular generalization of the atomic double-exchange and superexchange interactions applied to an arbitrary bipartite lattice host
Pinning induced by inter-domain wall interactions in planar magnetic nanowires
Hayward, T.J.; Bryan, M.T.; Fry, P.W.; Fundi, P.M.; Gibbs, M.R.J.; Allwood, D.A.; Im, M.-Y.; Fischer, P.
2009-10-30
We have investigated pinning potentials created by inter-domain wall magnetostatic interactions in planar magnetic nanowires. We show that these potentials can take the form of an energy barrier or an energy well depending on the walls' relative monopole moments, and that the applied magnetic fields required to overcome these potentials are significant. Both transverse and vortex wall pairs are investigated and it is found that transverse walls interact more strongly due to dipolar coupling between their magnetization structures. Simple analytical models which allow the effects of inter-domain wall interactions to be estimated are also presented.
Y. V. Stadnik; V. V. Flambaum
2015-02-24
We show that the interaction of an axion field, or in general a pseudoscalar field, with the axial-vector current generated by an electron through a derivative-type coupling can give rise to a time-dependent mixing of opposite-parity states in atomic and molecular systems. Likewise, the analogous interaction of an axion field with the axial-vector current generated by a nucleon can give rise to time-dependent mixing of opposite-parity states in nuclear systems. This mixing can induce oscillating electric dipole moments, oscillating parity non-conservation effects and oscillating anapole moments in such systems. By adjusting the energy separation between the opposite-parity states of interest to match the axion mass energy, axion-induced experimental observables can be enhanced by many orders of magnitude. Oscillating atomic electric dipole moments can also be generated by axions through hadronic mechanisms, namely the P,T-violating nucleon-nucleon interaction and through the axion-induced electric dipole moments of valence nucleons, which comprise the nuclei. The axion field is modified by the Earth's gravitational field. The interaction of the spin of either an electron or nucleon with this modified axion field leads to axion-induced observable effects. These effects, which are of the form $\\mathbf{g} \\cdot \\mathbf{\\sigma}$, differ from the axion-wind effect, which has the form $\\mathbf{p}_{\\textrm{a}} \\cdot \\mathbf{\\sigma}$.
Chakrabarti, Sudipto; Pal, Amlan J.
2014-01-06
We form a monolayer of magnetic organic molecules and immobilize their moments pointing either upwards or downwards with respect to the substrate through an electrostatic-binding process. Such a monolayer is probed with a scanning tunneling microscope tip, which is also magnetized with the magnetization vector pointing towards (or away from) apex of the tip. From spin-polarized tunneling current, we show that the current was higher when magnetization vectors of the tip and molecules were parallel as compared to that when they were anti-parallel. We show that for tunneling of spin-polarized electrons, aligned organic molecular magnets can act as a valve.
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SUPERCONDUCTING MAGNETIC ENERGY STORAGE
Hassenzahl, W.
2011-01-01
Superconducting 30-MJ Energy Storage Coil", Proc. 19 80 ASC,Superconducting Magnetic Energy Storage Plant", IEEE Trans.SlIperconducting Magnetic Energy Storage Unit", in Advances
Low-energy planar magnetic defects in BaFe2As2: Nanotwins, twins, antiphase, and domain boundaries
Khan, S. N. [Ames Laboratory] [Ames Laboratory; Alam, A. [Ames Laboratory] [Ames Laboratory; Johnson, Duane D. [University of Illinois, Urbana-Champaign] [University of Illinois, Urbana-Champaign
2013-01-01
In BaFe2As2, structural and magnetic planar defects begin to proliferate below the structural phase transition, affecting descriptions of magnetism and superconductivity.We study, using density-functional theory, the stability and magnetic properties of competing antiphase and domain boundaries, twins and isolated nanotwins (twin nuclei), and spin excitations proposed and/or observed. These nanoscale defects have a very low surface energy (22 210 m Jm 2), with twins favorable to the mesoscale. Defects exhibit smaller moments confined near their boundaries making a uniform-moment picture inappropriate for long-range magnetic order in real samples. Nanotwins explain features in measured pair distribution functions so should be considered when analyzing scattering data. All these defects can be weakly mobile and/or can have fluctuations that lower
Magnetic order and electronic structure of 5d3 double perovskite Sr2ScOsO6
Calder, Stuart A; Morrow, Ryan; Taylor, Alice E; Lumsden, Mark D; Woodward, Patrick; Christianson, Andrew D; Singh, David J
2015-01-01
The magnetic susceptibility, crystal and magnetic structures, and electronic structure of double perovskite Sr2ScOsO6 are reported. Using both neutron and x-ray powder diffraction we find that the crystal structure is monoclinic P21/n from 3.5 to 300 K. Magnetization measurements indicate an antiferromagnetic transition at TN=92 K, one of the highest transition temperatures of any double perovskite hosting only one magnetic ion. Type I antiferromagnetic order is determined by neutron powder diffraction, with an Os moment of only 1.6(1) muB, close to half the spin-only value for a crystal field split 5d electron state with t2g^3 ground state. Density functional calculations show that this reduction is largely the result of strong Os-O hybridization, with spin-orbit coupling responsible for only a ~0.1 muB reduction in the moment.
Magnetism in undoped ZnS studied from density functional theory
Xiao, Wen-Zhi E-mail: llwang@hun.edu.cn; Rong, Qing-Yan; Xiao, Gang; Wang, Ling-ling E-mail: llwang@hun.edu.cn; Meng, Bo
2014-06-07
The magnetic property induced by the native defects in ZnS bulk, thin film, and quantum dots are investigated comprehensively based on density functional theory within the generalized gradient approximation + Hubbard U (GGA?+?U) approach. We find the origin of magnetism is closely related to the introduction of hole into ZnS systems. The relative localization of S-3p orbitals is another key to resulting in unpaired p-electron, due to Hund's rule. For almost all the ZnS systems under study, the magnetic moment arises from the S-dangling bonds generated by Zn vacancies. The charge-neutral Zn vacancy, Zn vacancy in 1? charge sate, and S vacancy in the 1+ charge sate produce a local magnetic moment of 2.0, 1.0, and 1.0??{sub B}, respectively. The Zn vacancy in the neutral and 1? charge sates are the important cause for the ferromagnetism in ZnS bulk, with a Curie temperature (T{sub C}) above room temperature. For ZnS thin film with clean (111) surfaces, the spins on each surface are ferromagnetically coupled but antiferromagnetically coupled between two surfaces, which is attributable to the internal electric field between the two polar (111) surfaces of the thin film. Only surface Zn vacancies can yield local magnetic moment for ZnS thin film and quantum dot, which is ascribed to the surface effect. Interactions between magnetic moments on S-3p states induced by hole-doping are responsible for the ferromagnetism observed experimentally in various ZnS samples.
Improving Cyber-Security of Smart Grid Systems via Anomaly Detection and Linguistic Domain Knowledge
Ondrej Linda; Todd Vollmer; Milos Manic
2012-08-01
The planned large scale deployment of smart grid network devices will generate a large amount of information exchanged over various types of communication networks. The implementation of these critical systems will require appropriate cyber-security measures. A network anomaly detection solution is considered in this work. In common network architectures multiple communications streams are simultaneously present, making it difficult to build an anomaly detection solution for the entire system. In addition, common anomaly detection algorithms require specification of a sensitivity threshold, which inevitably leads to a tradeoff between false positives and false negatives rates. In order to alleviate these issues, this paper proposes a novel anomaly detection architecture. The designed system applies the previously developed network security cyber-sensor method to individual selected communication streams allowing for learning accurate normal network behavior models. Furthermore, the developed system dynamically adjusts the sensitivity threshold of each anomaly detection algorithm based on domain knowledge about the specific network system. It is proposed to model this domain knowledge using Interval Type-2 Fuzzy Logic rules, which linguistically describe the relationship between various features of the network communication and the possibility of a cyber attack. The proposed method was tested on experimental smart grid system demonstrating enhanced cyber-security.
Large-Scale Magnetic Fields, Dark Energy and QCD
Federico R. Urban; Ariel R. Zhitnitsky
2010-08-20
Cosmological magnetic fields are being observed with ever increasing correlation lengths, possibly reaching the size of superclusters, therefore disfavouring the conventional picture of generation through primordial seeds later amplified by galaxy-bound dynamo mechanisms. In this paper we put forward a fundamentally different approach that links such large-scale magnetic fields to the cosmological vacuum energy. In our scenario the dark energy is due to the Veneziano ghost (which solves the $U(1)_A$ problem in QCD). The Veneziano ghost couples through the triangle anomaly to the electromagnetic field with a constant which is unambiguously fixed in the standard model. While this interaction does not produce any physical effects in Minkowski space, it triggers the generation of a magnetic field in an expanding universe at every epoch. The induced energy of the magnetic field is thus proportional to cosmological vacuum energy: $\\rho_{EM}\\simeq B^2 \\simeq (\\frac{\\alpha}{4\\pi})^2 \\rho_{DE}$, $\\rho_{DE}$ hence acting as a source for the magnetic energy $\\rho_{EM}$. The corresponding numerical estimate leads to a magnitude in the nG range. There are two unique and distinctive predictions of our proposal: an uninterrupted active generation of Hubble size correlated magnetic fields throughout the evolution of the universe; the presence of parity violation on the enormous scales $1/H$, which apparently has been already observed in CMB. These predictions are entirely rooted into the standard model of particle physics.
Cryogenic techniques for large superconducting magnets in space
Green, M.A.
1988-12-01
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.
Neutron in a Strong Magnetic Field: Finite Volume Effects
Brian C. Tiburzi
2014-03-04
We investigate the neutron's response to magnetic fields on a torus with the aid of chiral perturbation theory, and expose effects from non-vanishing holonomies. The determination of such effects necessitates non-perturbative treatment of the magnetic field; and, to this end, a strong-field power counting is employed. Using a novel coordinate-space method, we find the neutron propagates in a coordinate-dependent effective potential that we obtain by integrating out charged pions winding around the torus. Knowledge of these finite volume effects will aid in the extraction of neutron properties from lattice QCD computations in external magnetic fields. In particular, we obtain finite volume corrections to the neutron magnetic moment and magnetic polarizability. These quantities have not been computed correctly in the literature. In addition to effects from non-vanishing holonomies, finite volume corrections depend on the magnetic flux quantum through an Aharonov-Bohm effect. We make a number of observations that demonstrate the importance of non-perturbative effects from strong magnetic fields currently employed in lattice QCD calculations. These observations concern neutron physics in both finite and infinite volume.
Nematic order of model goethite nanorods in a magnetic field
H. H. Wensink; G. J. Vroege
2005-01-18
We explore the nematic order of model goethite nanorods in an external magnetic field within Onsager-Parsons density functional theory. The goethite rods are represented by monodisperse, charged spherocylinders with a permanent magnetic moment along the rod main axis, forcing the particles to align parallel to the magnetic field at low field strength. The intrinsic diamagnetic susceptibility anisometry of the rods is negative which leads to a preferred perpendicular orientation at higher field strength. It is shown that these counteracting effects may give rise to intricate phase behavior, including a pronounced stability of biaxial nematic order and the presence of reentrant phase transitions and demixing phenomena. The effect of the applied field on the nematic-to-smectic transition will also be addressed.
Entangled states, Lorentz transformations, Spin-precession in magnetic fields
A. Chakrabarti
2009-03-07
Two positive mass, spin $\\frac 12$ particles created in an entangled state are studied in the presence of a constant magnetic field inducing distinct precessions, depending on the respective momenta, of the two spins. The charge and anomalous magnetic moment of each particle is taken into account. Consequences for entanglement and, more generally, on correlations, are derived. We start, however, with a compact derivation of the effects of Lorentz transformations on such entangled states, though that has been studied by several authors. Our formalism displays conveniently the analogies and the differences between the two cases. Moreover, combining the two, one obtains the case of constant, orthogonal electric and magnetic fields. More general perspectives are evoked in the concluding remarks.
Quality Control of Temperature and Salinity from CTD based on Anomaly Detection
Castelão, Guilherme P
2015-01-01
The CTD is a set of sensors used by oceanographers to measure fundamental hydrographic properties of the oceans. It is characterized by a high precision product, only achieved if a quality control procedure identifies and removes the bad samples. Such procedure has been traditionally done by a sequence of independent tests that minimize false negatives. It is here proposed a novel approach to identify the bad samples as anomalies in respect to the typical behavior of good data. Several tests are combined into a single multidimensional evaluation to provide a more flexible classification criterion. The traditional approach is reproduced with an error of 0.04%, otherwise, the Anomaly Detection technique surpasses the reference if calibrated by visual inspection. CoTeDe is a Python package developed to apply the traditional and the Anomaly Detection quality control of temperature and salinity data from CTD, and can be extended to XBT, ARGO and other sensors.
New Horizons in Gravity: The Trace Anomaly, Dark Energy and Condensate Stars
Mottola, Emil
2010-01-01
General Relativity receives quantum corrections relevant at macroscopic distance scales and near event horizons. These arise from the conformal scalar degrees of freedom in the extended effective field theory of gravity generated by the trace anomaly of massless quantum fields in curved space. The origin of these conformal scalar degrees of freedom as massless poles in two-particle intermediate states of anomalous amplitudes in flat space is exposed. At event horizons the conformal anomaly scalar degrees of freedom can have macroscopically large effects on the geometry, potentially removing the classical event horizon of black hole and cosmological spacetimes, replacing them with a quantum boundary layer where the effective value of the gravitational vacuum energy density can change. In the effective theory, the cosmological term becomes a dynamical condensate, whose value depends upon boundary conditions near the horizon. In the conformal phase where the anomaly induced fluctutations dominate, and the conden...