Mapping the magnetic field vector in a fountain clock
Gertsvolf, Marina; Marmet, Louis [National Research Council of Canada, Ottawa, Ontario K1A 0R6 (Canada)
2011-12-15
We show how the mapping of the magnetic field vector components can be achieved in a fountain clock by measuring the Larmor transition frequency in atoms that are used as a spatial probe. We control two vector components of the magnetic field and apply audio frequency magnetic pulses to localize and measure the field vector through Zeeman spectroscopy.
Alexey A. Magazev; Vitaly V. Mikheyev; Igor V. Shirokov
2015-08-06
Methods of construction of the composition function, left- and right-invariant vector fields and differential 1-forms of a Lie group from the structure constants of the associated Lie algebra are proposed. It is shown that in the second canonical coordinates these problems are reduced to the matrix inversions and matrix exponentiations, and the composition function can be represented in quadratures. Moreover, it is proven that the transition function from the first canonical coordinates to the second canonical coordinates can be found by quadratures.
Full vector low-temperature magnetic measurements of geologic materials
Feinberg, Joshua M; Solheid, Peter A; Swanson-Hysell, Nicholas L; Jackson, Mike J; Bowles, Julie A
2015-01-01
511. FEINBERG ET AL. : THREE-AXIS LOW-TEMPERATURE REMANENCEof pyrrhotite as determined by low- and high-field experi-10.1029/, Full vector low-temperature magnetic measurements
Coexistence of Multiple Phases in Magnetized Quark Matter with Vector Repulsion
Denke, Robson Z
2015-01-01
We explore the phase structure of dense magnetized quark matter when a repulsive vector interaction, parametrized by $G_V$, is present. Our results show that for a given magnetic field intensity ($B$) one may find a value of $G_V$ for which quark matter may coexist at three different baryonic density values leading to the appearance of two triple points in the phase diagram which have not been observed before. Another novel result is that at high pressure and low temperature we observe a first order transition which presents a negative slope in the $P-T$ that is reminiscent of the solid-liquid transition line observed within the water phase diagram. These unusual patterns occur for $G_V$ and $B$ values which lie within the range presently considered in many investigations related to the study of magnetars.
Deriving Potential Coronal Magnetic Fields from Vector Magnetograms
Welsch, Brian T
2015-01-01
The minimum-energy configuration for the magnetic field above the solar photosphere is curl-free (hence, by Ampere's law, also current-free), so can be represented as the gradient of a scalar potential. Since magnetic fields are divergence free, this scalar potential obeys Laplace's equation, given an appropriate boundary condition (BC). With measurements of the full magnetic vector at the photosphere, it is possible to employ either Neumann or Dirichlet BCs there. Historically, the Neumann BC was used, since available line-of-sight magnetic field measurements approximated the radial field needed for the Neumann BC. Since each BC fully determines the 3D vector magnetic field, either choice will, in general, be inconsistent with some aspect of the observed field on the boundary, due to the presence of both currents and noise in the observed field. We present a method to combine solutions from both Dirichlet and Neumann BCs to determine a hybrid potential field that minimizes the integrated square of the residu...
Vector Magnetic Fields and Electric Currents from the Imaging Vector Magnetograph
Jing Li; A. A. van Ballegooijen; Don Mickey
2008-11-01
First, we describe a general procedure to produce high quality vector magnetograms using the Imaging Vector Magnetograph (IVM) at Mees Solar Observatory. At the spatial resolution 2"x2", the Stokes Q,U,V uncertainty reaches 0.001-0.0005 in time-averaged data over 1-hour in the quiet Sun. When vector magnetic fields are inferred from the time-averaged Stokes spectral images of FeI 6302.5A, the resulting uncertainties are on the order of 10 G for the longitudinal fields, 40 G for the transverse field strength and 9 degree for the magnetic azimuth. The magnetic field inversion used in this work is the "Triplet" code, which was developed and implemented in the IVM software package by the late Barry J. LaBonte. The inversion code is described in detail in the Appendix. Second, we solve for the absolute value of the vertical electric current density, |Jz|, accounting for the above IVM problems, for two different active regions. One is a single sunspot region (NOAA 10001 observed on 20 June 2002) while the other is a more complex, quadrupolar region (NOAA10030 observed on 15 July 2002). We use a calculation that does not require disambiguation of 180 degree in the transverse field directions. The |Jz| uncertainty is on the order of 7.0 mA m^-2. The vertical current density increases with increasing vertical magnetic field. The rate of increase is about 1 -2 times as large in the quadrupolar NOAA 10030 region as in the simple NOAA 10001, and it is more spatially variable over NOAA 10030 than over NOAA 10001.
Height variation of the vector magnetic field in solar spicules
Suarez, D Orozco; Bueno, J Trujillo
2015-01-01
Proving the magnetic configuration of solar spicules has hitherto been difficult due to the lack of spatial resolution and image stability during off-limb ground-based observations. We report spectropolarimetric observations of spicules taken in the He I 1083 nm spectral region with the Tenerife Infrared Polarimeter II at the German Vacuum Tower Telescope of the Observatorio del Teide (Tenerife; Canary Islands; Spain). The data provide the variation with geometrical height of the Stokes I, Q, U, and V profiles whose encoded information allows the determination of the magnetic field vector by means of the HAZEL inversion code. The inferred results show that the average magnetic field strength at the base of solar spicules is about 80 gauss and then it decreases rapidly with height to about 30 gauss at a height of 3000 km above the visible solar surface. Moreover, the magnetic field vector is close to vertical at the base of the chromosphere and has mid inclinations (about 50 degree) above 2 Mm height.
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
over scalar mode where one pair of operands are being operated on sequentially. Compilers can auto-vectorize loops for you that are considered safe for vectorization. In case...
Predicting the magnetic vectors within coronal mass ejections arriving at Earth
Savani, N P; Szabo, A; Mays, M L; Thompson, B J; Richardson, I G; Evans, R; Pulkkinen, A; Nieves-Chinchilla, T
2015-01-01
The process by which the Sun affects the terrestrial environment on short timescales is predominately driven by the amount of magnetic reconnection between the solar wind and Earth's magnetosphere. Reconnection occurs most efficiently when the solar wind magnetic field has a southward component. The most severe impacts are during the arrival of a coronal mass ejection (CME) when the magnetosphere is both compressed and magnetically connected to the heliospheric environment, leading to disruptions to, for example, power grids and satellite navigation. Unfortunately, forecasting magnetic vectors within coronal mass ejections remains elusive. Here we report how, by combining a statistically robust helicity rule for a CME's solar origin with a simplified flux rope topology the magnetic vectors within the Earth-directed segment of a CME can be predicted. In order to test the validity of this proof-of-concept architecture for estimating the magnetic vectors within CMEs, a total of eight CME events (between 2010 and...
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Intrinsic math functions such as 'cos()', 'sin()', etc. are allowed because such library functions are usually vectorized versions. A loop containing a function that is...
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.
A Holographic Study on Vector Condensate Induced by a Magnetic Field
Rong-Gen Cai; Song He; Li Li; Li-Fang Li
2013-12-02
We study a holographic model with vector condensate by coupling the anti-de Sitter gravity to an Abelian gauge field and a charged vector field in $(3+1)$ dimensional spacetime. In this model there exists a non-minimal coupling of the vector filed to the gauge field. We find that there is a critical temperature below which the charged vector condenses via a second order phase transition. The DC conductivity becomes infinite and the AC conductivity develops a gap in the condensed phase. We study the effect of a background magnetic field on the system. It is found that the background magnetic field can induce the condensate of the vector field even in the case without chemical potential/charge density. In the case with non-vanishing charge density, the transition temperature raises with the applied magnetic field, and the condensate of the charged vector operator forms a vortex lattice structure in the spatial directions perpendicular to the magnetic field.
Effective nucleon-nucleon interaction and low-lying nuclear magnetic states
C. Maieron; V. De Donno; G Co'; M. Anguiano; A. M. Lallena; M. Moreno Torres
2009-01-16
We present a calculation of low energy magnetic states of doubly-closed-shell nuclei. Our results have been obtained within the random phase approximation using different nucleon-nucleon interactions, having zero- or finite-range and including a possible contribution in the tensor channel.
VFISV: Very Fast Inversion of the Stokes Vector for the Helioseismic and Magnetic Imager
Borrero, J M; Kubo, M; Socas-Navarro, H; Schou, J; Couvidat, S; Bogart, R
2009-01-01
In this paper we describe in detail the implementation and main properties of a new inversion code for the polarized radiative transfer equation (VFISV: Very Fast inversion of the Stokes vector). VFISV will routinely analyze pipeline data from the Helioseismic and Magnetic Imager (HMI) on-board of the Solar Dynamics Observatory (SDO). It will provide full-disk maps (4096$\\times$4096 pixels) of the magnetic field vector on the Solar Photosphere every 10 minutes. For this reason VFISV is optimized to achieve an inversion speed that will allow it to invert 16 million pixels every 10 minutes with a modest number (approx. 50) of CPUs. Here we focus on describing a number of important details, simplifications and tweaks that have allowed us to significantly speed up the inversion process. We also give details on tests performed with data from the spectropolarimeter on-board of the Hinode spacecraft.
He I vector magnetic field maps of a sunspot and its superpenumbral fine-structure
Schad, T A; Lin, H; Tritschler, A
2015-01-01
Advanced inversions of high-resolution spectropolarimetric observations of the He I triplet at 1083 nm are used to generate unique maps of the chromospheric magnetic field vector across a sunspot and its superpenumbral canopy. The observations were acquired by the Facility Infrared Spectropolarimeter (FIRS) at the Dunn Solar Telescope (DST) on 29 January 2012. Multiple atmospheric models are employed in the inversions, as superpenumbral Stokes profiles are dominated by atomic-level polarization while sunspot profiles are Zeeman-dominated but also exhibit signatures perhaps induced by symmetry breaking effects of the radiation field incident on the chromospheric material. We derive the equilibrium magnetic structure of a sunspot in the chromosphere, and further show that the superpenumbral magnetic field does not appear finely structured, unlike the observed intensity structure. This suggests fibrils are not concentrations of magnetic flux but rather distinguished by individualized thermalization. We also dire...
Exchange coupling in hybrid anisotropy magnetic multilayers quantified by vector magnetometry
Morrison, C. Miles, J. J.; Thomson, T.; Anh Nguyen, T. N.; Fang, Y.; Dumas, R. K.; Åkerman, J.
2015-05-07
Hybrid anisotropy thin film heterostructures, where layers with perpendicular and in-plane anisotropy are separated by a thin spacer, are novel materials for zero/low field spin torque oscillators and bit patterned media. Here, we report on magnetization reversal and exchange coupling in a archetypal Co/Pd (perpendicular)-NiFe (in-plane) hybrid anisotropy system studied using vector vibrating sample magnetometry. This technique allows us to quantify the magnetization reversal in each individual magnetic layer, and measure of the interlayer exchange as a function of non-magnetic spacer thickness. At large (>1?nm) spacer thicknesses Ruderman-Kittel-Kasuya-Yosida-like exchange dominates, with orange-peel coupling providing a significant contribution only for sub-nm spacer thickness.
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.
Jiang, Chaowei; Wu, S. T.; Hu, Qiang; Feng, Xueshang E-mail: wus@uah.edu E-mail: fengx@spaceweather.ac.cn
2014-05-10
Solar filaments are commonly thought to be supported in magnetic dips, in particular, in those of magnetic flux ropes (FRs). In this Letter, based on the observed photospheric vector magnetogram, we implement a nonlinear force-free field (NLFFF) extrapolation of a coronal magnetic FR that supports a large-scale intermediate filament between an active region and a weak polarity region. This result is a first, in the sense that current NLFFF extrapolations including the presence of FRs are limited to relatively small-scale filaments that are close to sunspots and along main polarity inversion lines (PILs) with strong transverse field and magnetic shear, and the existence of an FR is usually predictable. In contrast, the present filament lies along the weak-field region (photospheric field strength ? 100 G), where the PIL is very fragmented due to small parasitic polarities on both sides of the PIL and the transverse field has a low signal-to-noise ratio. Thus, extrapolating a large-scale FR in such a case represents a far more difficult challenge. We demonstrate that our CESE-MHD-NLFFF code is sufficient for the challenge. The numerically reproduced magnetic dips of the extrapolated FR match observations of the filament and its barbs very well, which strongly supports the FR-dip model for filaments. The filament is stably sustained because the FR is weakly twisted and strongly confined by the overlying closed arcades.
Hinode Observations of Vector Magnetic Field Change Associated with a Flare on 2006 December 13
Masahito Kubo; Takaaki Yokoyama; Yukio Katsukawa; Bruce W Lites; Saku Tsuneta; Yoshinori Suematsu; Kiyoshi Ichimoto; Toshifumi Shimizu; Shin'ichi Nagata; Theodore D Tarbell; Richard A Shine; Alan M Title; David Elmore
2007-09-17
Continuous observations of a flare productive active region 10930 were successfully carried out with the Solar Optical Telescope onboard the Hinode spacecraft during 2007 December 6 to 19. We focus on the evolution of photospheric magnetic fields in this active region, and magnetic field properties at the site of the X3.4 class flare, using a time series of vector field maps with high spatial resolution. The X3.4 class flare occurred on 2006 December 13 at the apparent collision site between the large, opposite polarity umbrae. Elongated magnetic structures with alternatingly positive and negative polarities resulting from flux emergence appeared one day before the flare in the collision site penumbra. Subsequently, the polarity inversion line at the collision site became very complicated. The number of bright loops in Ca II H increased during the formation of these elongated magnetic structures. The flare ribbons and bright loops evolved along the polarity inversion line and one footpoint of the bright loop was located in a region having a large departure of field azimuth angle with respect to its surroundings. The SOT observations with high spatial resolution and high polarization precision reveal temporal change in fine structure of magnetic fields at the flare site: some parts of the complicated polarity inversion line then disappeared, and in those regions the azimuth angle of photospheric magnetic field changed by about 90 degrees, becoming more spatially uniform within the collision site.
SOLAR FLARE PREDICTION USING SDO/HMI VECTOR MAGNETIC FIELD DATA WITH A MACHINE-LEARNING ALGORITHM
Bobra, M. G.; Couvidat, S.
2015-01-10
We attempt to forecast M- and X-class solar flares using a machine-learning algorithm, called support vector machine (SVM), and four years of data from the Solar Dynamics Observatory's Helioseismic and Magnetic Imager, the first instrument to continuously map the full-disk photospheric vector magnetic field from space. Most flare forecasting efforts described in the literature use either line-of-sight magnetograms or a relatively small number of ground-based vector magnetograms. This is the first time a large data set of vector magnetograms has been used to forecast solar flares. We build a catalog of flaring and non-flaring active regions sampled from a database of 2071 active regions, comprised of 1.5 million active region patches of vector magnetic field data, and characterize each active region by 25 parameters. We then train and test the machine-learning algorithm and we estimate its performances using forecast verification metrics with an emphasis on the true skill statistic (TSS). We obtain relatively high TSS scores and overall predictive abilities. We surmise that this is partly due to fine-tuning the SVM for this purpose and also to an advantageous set of features that can only be calculated from vector magnetic field data. We also apply a feature selection algorithm to determine which of our 25 features are useful for discriminating between flaring and non-flaring active regions and conclude that only a handful are needed for good predictive abilities.
Jacobi-Lie systems: Fundamentals and low-dimensional classification
F. J. Herranz; J. de Lucas; C. Sardon
2015-04-03
A Lie system is a system of differential equations describing the integral curves of a $t$-dependent vector field taking values in a finite-dimensional real Lie algebra of vector fields, a Vessiot-Guldberg Lie algebra. We define and analyze Lie systems possessing a Vessiot-Guldberg Lie algebra of Hamiltonian vector fields relative to a Jacobi manifold, the hereafter called Jacobi-Lie systems. We classify Jacobi-Lie systems on $\\mathbb{R}$ and $\\mathbb{R}^2$. Our results shall be illustrated through examples of physical and mathematical interest.
Energy Levels and Wave Functions of Vector Bosons in Homogeneous Magnetic Field
K. Sogut; A. Havare; I. Acikgoz
2001-10-24
We aimed to obtain the energy levels of spin-1 particles moving in a constant magnetic field. The method used here is completely algebraic. In the process to obtain the energy levels the wave function is choosen in terms of Laguerre Polynomials.
Quantum observables, Lie algebra homology and TQFT
Albert Schwarz
1999-04-25
Let us consider a Lie (super)algebra $G$ spanned by $T_{\\alpha}$ where $T_{\\alpha}$ are quantum observables in BV-formalism. It is proved that for every tensor $c^{\\alpha_1...\\alpha_k}$ that determines a homology class of the Lie algebra $G$ the expression $c^{\\alpha_1...\\alpha_k}T_{\\alpha _1}...T_{\\alpha_k}$ is again a quantum observables. This theorem is used to construct quantum observables in BV sigma-model. We apply this construction to explain Kontsevich's results about the relation between homology of the Lie algebra of Hamiltonian vector fields and topological invariants of manifolds.
VB-algebroids and representation theory of Lie algebroids
Gracia-Saz, Alfonso
2008-01-01
A VB-algebroid is essentially defined as a Lie algebroid object in the category of vector bundles. There is a one-to-one correspondence between VB-algebroids and certain flat Lie algebroid superconnections, up to a natural notion of equivalence. In this setting, we are able to construct characteristic classes, which in special cases reproduce characteristic classes constructed by Crainic and Fernandes. We give a complete classification of regular VB-algebroids, and in the process we obtain another characteristic class of Lie algebroids that does not appear in the ordinary representation theory of Lie algebroids.
Tomislav Ivezic
2012-11-02
In the first part of this paper we review the fundamental difference between the usual transformations of the three-dimensional (3D) vectors of the electric field $\\mathbf{E}$, the magnetic field $\\mathbf{B}$, the polarization $\\mathbf{P}$, the magnetization $\\mathbf{M}$ and the Lorentz transformations of the 4D geometric quantities, vectors E, B, P, M, with many additional explanations and several new results. In the second part, we have discussed the existence of the electric field vector E outside a stationary superconducting wire with a steady current and also different experiments for the detection of such electric fields. Furthermore, a fundamental prediction of the existence of the external electric field vector E from a stationary permanent magnet is considered. These electric fields are used for the resolution of the "charge-magnet paradox" with 4D geometric quantities for a qualitative explanation of the Aharonov-Bohm effect in terms of fields and not, as usual, in terms of the vector potential and for a qualitative explanation that the particle interference is not a test of a Lorentz-violating model of electrodynamics according to which a magnetic solenoid generates not only a static magnetic field but also a static electric field.
The 3D Vector Potential, Magnetic Field and Stored Energy in a Thin cos2 theta Coil Array
Caspi, S.
2011-01-01
quadrupole magnets with thin Cos(20) current sheet placed at= canst. const. I:: JO. ,m cos WmZ m=l and the flow linesl I:: JOz,m m=l sin 2()0 JOz,m cos WmZ where ()o denotes the
Lie algebras associated to fiber-type arrangements
Daniel C. Cohen; Frederick R. Cohen; Miguel Xicotencatl
2000-05-10
Given a hyperplane arrangement in a complex vector space of dimension n, there is a natural associated arrangement of codimension k subspaces in a complex vector space of dimension k*n. Topological invariants of the complement of this subspace arrangement are related to those of the complement of the original hyperplane arrangement. In particular, if the hyperplane arrangement is fiber-type, then, apart from grading, the Lie algebra obtained from the descending central series for the fundamental group of the complement of the hyperplane arrangement is isomorphic to the Lie algebra of primitive elements in the homology of the loop space for the complement of the associated subspace arrangement. Furthermore, this last Lie algebra is given by the homotopy groups modulo torsion of the loop space of the complement of the subspace arrangement. Looping further yields an associated Poisson algebra, and generalizations of the "universal infinitesimal Poisson braid relations."
String Homology and Lie Algebra Structures
Tabing, Felicia
2015-01-01
Vilkovisky Lie algebra structure on the loop homol- ogy ofHOMOLOGY AND LIE ALGEBRA STRUCTURES A dissertation submittedLie Algebra Structure . . . . . . . . . . . . . . . . .
Guilfoyle, R.A.; Smith, L.M.
1994-12-27
A vector comprising a filamentous phage sequence containing a first copy of filamentous phage gene X and other sequences necessary for the phage to propagate is disclosed. The vector also contains a second copy of filamentous phage gene X downstream from a promoter capable of promoting transcription in a bacterial host. In a preferred form of the present invention, the filamentous phage is M13 and the vector additionally includes a restriction endonuclease site located in such a manner as to substantially inactivate the second gene X when a DNA sequence is inserted into the restriction site. 2 figures.
Reception of longitudinal vector potential radiation with a plasma antenna
Zimmerman, Robert K. Jr.
2013-07-28
To help resolve the long-running debate between physicists and engineers regarding the existence of the magnetic vector potential, herewith we describe an experiment demonstrating reception of time-harmonic vector potential radiation at 1.3 GHz.
Filiform Lie algebras of order 3
Navarro, R. M., E-mail: rnavarro@unex.es [Rosa María Navarro. Dpto. de Matemáticas, Universidad de Extremadura, Cáceres (Spain)
2014-04-15
The aim of this work is to generalize a very important type of Lie algebras and superalgebras, i.e., filiform Lie (super)algebras, into the theory of Lie algebras of order F. Thus, the concept of filiform Lie algebras of order F is obtained. In particular, for F = 3 it has been proved that by using infinitesimal deformations of the associated model elementary Lie algebra it can be obtained families of filiform elementary lie algebras of order 3, analogously as that occurs into the theory of Lie algebras [M. Vergne, “Cohomologie des algèbres de Lie nilpotentes. Application à l’étude de la variété des algèbres de Lie nilpotentes,” Bull. Soc. Math. France 98, 81–116 (1970)]. Also we give the dimension, using an adaptation of the sl(2,C)-module Method, and a basis of such infinitesimal deformations in some generic cases.
Truth and lies in cinema verite
Majoros, Michael A
1985-01-01
1985 in partial fulfillment of the requirements for the degree of Master of Science in Visual Studies. This thesis consists of two sections: Truth and Lies, and the making of Everything Must Change. Truth and lies traces ...
Cremmer-Gervais Quantum Lie Algebra
O. Ogievetsky; T. Popov
2009-05-06
We describe a quantum Lie algebra based on the Cremmer-Gervais R-matrix. The algebra arises upon a restriction of an infinite-dimensional quantum Lie algebra.
On Characters of F_4 Lie Algebra
M. Gungormez; H. R. Karadayi
2008-10-15
In a previous work, we have given an explicit method to obtain irreducible characters of finite Lie algebras without referring to Weyl character formula. Irreducible characters of $G_2$ Lie algebra has been given as an example. The work is now extended to somewhat more complicated case of $F_4$ Lie algebra, in the same manner.
Broader source: Energy.gov [DOE]
Geeks, pay attention! We've got a BioEnergy Atlas, aerosols and climate, sour stuff, and 3D magnetic interactions in this edition of the Geek Up!
Fisher, George H; Bercik, David J; Kazachenko, Maria D; Lynch, Benjamin J; Welsch, Brian T; Hoeksema, J Todd; Hayashi, Keiji; Liu, Yang; Norton, Aimee A; Dalda, Alberto Sainz; Sun, Xudong; DeRosa, Marc L; Cheung, Mark C M
2015-01-01
The most violent space weather events (eruptive solar flares and coronal mass ejections) are driven by the release of free magnetic energy stored in the solar corona. Energy can build up on timescales of hours to days, and then may be suddenly released in the form of a magnetic eruption, which then propagates through interplanetary space, possibly impacting the Earth's space environment. Can we use the observed evolution of the magnetic and velocity fields in the solar photosphere to model the evolution of the overlying solar coronal field, including the storage and release of magnetic energy in such eruptions? The objective of CGEM, the Coronal Global Evolutionary Model, funded by the NASA/NSF Space Weather Modeling program, is to develop and evaluate such a model for the evolution of the coronal magnetic field. The evolving coronal magnetic field can then be used as a starting point for magnetohydrodynamic (MHD) models of the corona, which can then be used to drive models of heliospheric evolution and predi...
Automorphic Lie Algebras with dihedral symmetry
Vincent Knibbeler; Sara Lombardo; Jan A Sanders
2014-10-10
The concept of Automorphic Lie Algebras arises in the context of reduction groups introduced in the early 1980s in the field of integrable systems. Automorphic Lie Algebras are obtained by imposing a discrete group symmetry on a current algebra of Krichever-Novikov type. Past work shows remarkable uniformity between algebras associated to different reduction groups. For example, if the base Lie algebra is $\\mathfrak{sl}_2(\\mathbb{C})$ and the poles of the Automorphic Lie Algebra are restricted to an exceptional orbit of the symmetry group, changing the reduction group does not affect the Lie algebra structure. In the present research we fix the reduction group to be the dihedral group and vary the orbit of poles as well as the group action on the base Lie algebra. We find a uniform description of Automorphic Lie Algebras with dihedral symmetry, valid for poles at exceptional and generic orbits.
Walker, Thad Gilbert; Lancor, Brian Robert; Wyllie, Robert
2014-04-15
Precise measurements of a precessional rate of noble gas in a magnetic field is obtained by constraining the time averaged direction of the spins of a stimulating alkali gas to lie in a plane transverse to the magnetic field. In this way, the magnetic field of the alkali gas does not provide a net contribution to the precessional rate of the noble gas.
Pablant, Novimir Antoniuk
2010-01-01
1.1 Magnetic confinement fusion . . . . . . . . . . 1.2Stokes vector magnetic confinement fusion, 1 magnetic fieldare discussed. Magnetic confinement fusion The goal of
Homology of Lie algebra of supersymmetries and of super Poincare Lie algebra
M. V. Movshev; A. Schwarz; Renjun Xu
2011-08-09
We study the homology and cohomology groups of super Lie algebra of supersymmetries and of super Poincare Lie algebra in various dimensions. We give complete answers for (non-extended) supersymmetry in all dimensions $\\leq 11$. For dimensions $D=10,11$ we describe also the cohomology of reduction of supersymmetry Lie algebra to lower dimensions. Our methods can be applied to extended supersymmetry algebra.
Symplectic, orthogonal and linear Lie groups in Clifford algebra
D. S. Shirokov
2014-09-08
In this paper we prove isomorphisms between 5 Lie groups (of arbitrary dimension and fixed signatures) in Clifford algebra and classical matrix Lie groups - symplectic, orthogonal and linear groups. Also we obtain isomorphisms of corresponding Lie algebras.
Construction of n-Lie algebras and n-ary Hom-Nambu-Lie algebras
Joakim Arnlind; Abdenacer Makhlouf; Sergei Silvestrov
2011-03-01
We present a procedure to construct (n+1)-Hom-Nambu-Lie algebras from n-Hom-Nambu-Lie algebras equipped with a generalized trace function. It turns out that the implications of the compatibility conditions, that are necessary for this construction, can be understood in terms of the kernel of the trace function and the range of the twisting maps. Furthermore, we investigate the possibility of defining (n+k)-Lie algebras from n-Lie algebras and a k-form satisfying certain conditions.
Representations up to homotopy of Lie algebroids
Abad, Camilo Arias
2009-01-01
This is the first in a series of papers devoted to the study of the cohomology of classifying spaces. The aim of this paper is to introduce and study the notion of representation up to homotopy and to make sense of the adjoint representation of a Lie algebroid. Our construction is inspired by Quillen's notion of superconnection and fits into the general theory of structures up to homotopy. The advantage of considering such representations is that they are flexible and general enough to contain interesting examples which are the correct generalization of the corresponding notions for Lie algebras. They also allow one to identify seemingly ad-hoc constructions and cohomology theories as instances of the cohomology with coefficients in representations (up to homotopy). In particular, we show that the adjoint representation of a Lie algebroid makes sense as a representation up to homotopy and that, similar to the case of Lie algebras, the resulting cohomology controls the deformations of the Lie algebroid (i.e. i...
Poloidal divertor experiment with applied E vector x B vector/B/sup 2/ drift
Strait, E J
1980-05-01
It has been proposed that the E vector x B vector/B/sup 2/ drift arising from an externally applied electric field could be used in a tokamak or other toroidal device to remove plasma and impurities from the region near the wall and to reduce the amount of plasma striking the wall, either assisting or replacing a conventional magnetic field divertor. A poloidal magnetic divertor (without pumping chamber) was added to the Wisconsin Levitated Toroidal Octupole, and the octupole was operated with a tokamak-like magnetic field configuration (q = 0.7). A radial electric field was applied in the scrape-off zone, causing an E vector x B vector/B/sup 2/ drift with a large poloidal component. This reduced plasma flux reaching the wall of the toroid by up to a factor of 5 beyond the effect of the magnetic divertor, for divertor configurations with both high and low magnetic mirror ratios, in good agreement with a simple theoretical model. Plasma density and density scale length were also reduced in the scrape-off zone, in qualitative agreement with the model. This was not accompanied by any new instabilities in the scrape-off zone, nor by any appreciable degradation of confinement of the central plasma.
Diego Becciolini; Diogo Buarque Franzosi; Roshan Foadi; Mads T. Frandsen; Tuomas Hapola; Francesco Sannino
2015-07-15
We analyze the Large Hadron Collider (LHC) phenomenology of heavy vector resonances with a $SU(2)_L\\times SU(2)_R$ spectral global symmetry. This symmetry partially protects the electroweak S-parameter from large contributions of the vector resonances. The resulting custodial vector model spectrum and interactions with the standard model fields lead to distinct signatures at the LHC in the diboson, dilepton and associated Higgs channels.
Lie Algebras Unit code: MATH32112
Sidorov, Nikita
MATH32112 Lie Algebras Unit code: MATH32112 Credit Rating: 10 Unit level: Level 3 Teaching period MATH20212 - Algebraic Structures 2 (Compulsory) Additional Requirements MATH32112 pre-requisites Students are not permitted to take more than one of MATH32112, MATH42112 or MATH62112 for credit, either
Lie Algebras Unit code: MATH42112
Sidorov, Nikita
MATH42112 Lie Algebras Unit code: MATH42112 Credit Rating: 15 Unit level: Level 4 Teaching period MATH20212 - Algebraic Structures 2 (Compulsory) Additional Requirements MATH42112 pre-requisites Students are not permitted to take more than one of MATH32112 MATH42112 or MATH62112 for credit, either
Control Theory on Lie Groups Yuri L. Sachkov
Wagner, Stephan
Control Theory on Lie Groups Yuri L. Sachkov Program Systems Institute Russian Academy of Sciences on control theory on Lie groups. Controllability and optimal control for left-invariant problems on Lie for graduate students, no preliminary knowledge of control theory or Lie groups is assumed. SISSA 15/2006/M
Penny, Will
Sparsity Will Penny Relevance Vector Regression Kernel Prior Inference Sinc Example Visual Coding Learning Self-Inhibition Receptive Fields References Sparsity Will Penny 24th March 2011 #12;Sparsity Will Penny Relevance Vector Regression Kernel Prior Inference Sinc Example Visual Coding Maximum Likelihood
Wikswo, John
. A Superconducting QUantum Interference Device (SQUID) magnetometer has the ability to detect the magnetic fields
Vector generator scan converter
Moore, James M. (Livermore, CA); Leighton, James F. (Livermore, CA)
1990-01-01
High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O (input/output) channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardward for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold.
Vector generator scan converter
Moore, J.M.; Leighton, J.F.
1988-02-05
High printing speeds for graphics data are achieved with a laser printer by transmitting compressed graphics data from a main processor over an I/O channel to a vector generator scan converter which reconstructs a full graphics image for input to the laser printer through a raster data input port. The vector generator scan converter includes a microprocessor with associated microcode memory containing a microcode instruction set, a working memory for storing compressed data, vector generator hardware for drawing a full graphic image from vector parameters calculated by the microprocessor, image buffer memory for storing the reconstructed graphics image and an output scanner for reading the graphics image data and inputting the data to the printer. The vector generator scan converter eliminates the bottleneck created by the I/O channel for transmitting graphics data from the main processor to the laser printer, and increases printer speed up to thirty fold. 7 figs.
Convergence of Galerkin Variational Integrators for Vector Spaces and Lie Groups
Hall, James Brian
attraction. Kepler’s law of gravitation states that theSystem under these laws of gravitation is an open question.
Abelianizations of derivation Lie algebras of free associative algebra and free Lie algebra
Morita, Shigeyuki; Suzuki, Masaaki
2011-01-01
We determine the abelianizations of the following three kinds of graded Lie algebras in a certain stable range: derivations of the free associative algebra, derivations of the free Lie algebra and symplectic derivations of the free associative algebra. As an application of the last case, and by making use of a theorem of Kontsevich, we obtain a new proof of the vanishing theorem of Harer concerning the top rational cohomology group of the mapping class group with respect to its virtual cohomological dimension.
W3 Constructions on Affine Lie Algebras
A. Deckmyn; S. Schrans
1991-09-16
We use an argument of Romans showing that every Virasoro construction leads to realizations of $W_3$, to construct $W_3$ realizations on arbitrary affine Lie algebras. Solutions are presented for generic values of the level as well as for specific values of the level but with arbitrary parameters. We give a detailed discussion of the $\\aff{su}(2)_\\ell$-case. Finally, we discuss possible applications of these realizations to the construction of $W$-strings.
Alexander Milov
2008-12-21
This article reviews the current status of experimental results obtained in the measurement of light vector mesons produced in proton-proton and heavy ion collisions at different energies. The review is focused on two phenomena related to the light vector mesons; the modification of the spectral shape in search of Chiral symmetry restoration and suppression of the meson production in heavy ion collisions. The experimental results show that the spectral shape of light vector mesons are modified compared to the parameters measured in vacuum. The nature and the magnitude of the modification depends on the energy density of the media in which they are produced. The suppression patterns of light vector mesons are different from the measurements of other mesons and baryons. The mechanisms responsible for the suppression of the mesons are not yet understood. Systematic comparison of existing experimental results points to the missing data which may help to resolve the problem.
The Rahman polynomials and the Lie algebra sl_3(C)
Iliev, Plamen
2010-01-01
We interpret the Rahman polynomials in terms of the Lie algebra $sl_3(C)$. Using the parameters of the polynomials we define two Cartan subalgebras for $sl_3(C)$, denoted $H$ and $\\tilde{H}$. We display an antiautomorphism $\\dagger$ of $sl_3(C)$ that fixes each element of $H$ and each element of $\\tilde{H}$. We consider a certain finite-dimensional irreducible $sl_3(C)$-module $V$ consisting of homogeneous polynomials in three variables. We display a nondegenerate symmetric bilinear form $$ on $V$ such that $ = $ for all $\\beta \\in sl_3(C)$ and $\\xi,\\zeta \\in V$. We display two bases for $V$; one diagonalizes $H$ and the other diagonalizes $\\tilde{H}$. Both bases are orthogonal with respect to $$. We show that when $$ is applied to a vector in each basis, the result is a trivial factor times a Rahman polynomial evaluated at an appropriate argument. Thus for both transition matrices between the bases each entry is described by a Rahman polynomial. From these results we recover the previously known orthogonalit...
Carrigan, Charles R. (Tracy, CA)
2011-08-02
A determination is made of frequency components associated with a particular bearing or location resulting from sources emitting electromagnetic-wave energy for which a Poynting-Vector can be defined. The broadband frequency components associated with a specific direction or location of interest are isolated from other components in the power spectrum that are not associated with the direction or location of interest. The collection of pointing vectors can be used to characterize the source.
Quantization of extended SchrÄodinger-Virasoro Lie algebra
Lamei Yuan; Liji Zhou
2010-04-21
In present paper, we quantize the extended Schr\\"Aodinger-Virasoro Lie algebra in char- acteristic zero with its Lie bialgebra structures classified by Yuan-Wu-Xu, and get a new Hopf algebra.
Scattering and Bound State Green's Functions on a Plane via so(2,1) Lie Algebra
P. F. Borges; H. Boschi-Filho; A. N. Vaidya
2006-10-17
We calculate the Green's functions for the particle-vortex system, for two anyons on a plane with and without a harmonic regulator and in a uniform magnetic field. These Green's functions which describe scattering or bound states (depending on the specific potential in each case) are obtained exactly using an algebraic method related to the SO(2,1) Lie group. From these Green's functions we obtain the corresponding wave functions and for the bound states we also find the energy spectra.
Dual spaces of differential Lie algebras
Kupershmidt, B.A.
1982-01-01
We present a mathematical scheme which serves as an infinite-dimensional generalization of Poisson structures on dual spaces of finite-dimensional Lie algebras, which are well known and widely used in classical mechanics. These structures have recently appeared in the theory of Lax equations, long waves in hydrodynamics, and various other physical models: compressible hydrodynamics, magnetohydrodynamics, multifluid plasmas, elasticity, superfluid /sup 4/He and /sup 3/He-A, Ginzburg-Landau theory of superconductors, and classical chromohydrodynamics (the generalization of plasma physics to Yang-Mills interactions).
High performance magnetic bearing systems using high temperature superconductors
Abboud, R.G.
1998-05-05
Disclosed are a magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly. 7 figs.
High performance magnetic bearing systems using high temperature superconductors
Abboud, Robert G. (Barrington Hills, IL)
1998-01-01
A magnetic bearing apparatus and a method for providing at least one stabilizing force in a magnetic bearing structure with a superconducting magnetic assembly and a magnetic assembly, by providing a superconducting magnetic member in the superconducting magnetic assembly with a plurality of domains and arranging said superconducting magnetic member such that at least one domain has a domain C-axis vector alignment angularly disposed relative to a reference axis of the magnetic member in the magnetic assembly.
Stephani, H.
1988-07-01
The framework of Lie--Baecklund (or generalized) symmetries is used to give a unifying view of some of the known symmetries of Einstein's field equations for the vacuum or perfect fluid case (with a ..mu.. = p or a ..mu..+3p = 0 equation of state). These symmetries occur if space-time admits one or two Killing vectors (orthogonal or parallel, respectively, to the four-velocity in the perfect fluid case).
Homotopy commutative algebra and 2-nilpotent Lie algebra
Paris-Sud XI, Université de
Homotopy commutative algebra and 2-nilpotent Lie algebra Michel Dubois-Violette and Todor Popov commutative algebra, or C-algebra, on the cohomology of the free 2-nilpotent Lie algebra. The latter C-algebra Universal Enveloping Algebra (UEA) Ug of a finite dimensional positively graded Lie algebra g belongs
M. K. Georgoulis; Barry J. LaBonte
2007-06-27
We self-consistently derive the magnetic energy and relative magnetic helicity budgets of a three-dimensional linear force-free magnetic structure rooted in a lower boundary plane. For the potential magnetic energy we derive a general expression that gives results practically equivalent to those of the magnetic Virial theorem. All magnetic energy and helicity budgets are formulated in terms of surface integrals applied to the lower boundary, thus avoiding computationally intensive three-dimensional magnetic field extrapolations. We analytically and numerically connect our derivations with classical expressions for the magnetic energy and helicity, thus presenting a so-far lacking unified treatment of the energy/helicity budgets in the constant-alpha approximation. Applying our derivations to photospheric vector magnetograms of an eruptive and a noneruptive solar active regions, we find that the most profound quantitative difference between these regions lies in the estimated free magnetic energy and relative magnetic helicity budgets. If this result is verified with a large number of active regions, it will advance our understanding of solar eruptive phenomena. We also find that the constant-alpha approximation gives rise to large uncertainties in the calculation of the free magnetic energy and the relative magnetic helicity. Therefore, care must be exercised when this approximation is applied to photospheric magnetic field observations. Despite its shortcomings, the constant-alpha approximation is adopted here because this study will form the basis of a comprehensive nonlinear force-free description of the energetics and helicity in the active-region solar corona, which is our ultimate objective.
Observable primordial vector modes
Antony Lewis
2004-06-04
Primordial vector modes describe vortical fluid perturbations in the early universe. A regular solution exists with constant non-zero radiation vorticities on super-horizon scales. Baryons are tightly coupled to the photons, and the baryon velocity only decays by an order unity factor by recombination, leading to an observable CMB anisotropy signature via the Doppler effect. There is also a large B-mode CMB polarization signal, with significant power on scales larger than l~2000. This B-mode signature is distinct from that expected from tensor modes or gravitational lensing, and makes a primordial vector to scalar mode power ratio ~10^(-6) detectable. Future observations aimed at detecting large scale B-modes from gravitational waves will also be sensitive to regular vector modes at around this level.
Huang, Wei
. Keywords Active magnetic bearing, flywheel, vector instructions, API, multi-threaded execution. 1 application for feedback control is real-time control of active magnetic bearings (AMBs) in a high
Anisotropy of magnetic emulsions induced by magnetic and electric fields
Yury I. Dikansky; Alexander N. Tyatyushkin; Arthur R. Zakinyan
2011-09-10
The anisotropy of magnetic emulsions induced by simultaneously acting electric and magnetic fields is theoretically and experimentally investigated. Due to the anisotropy, the electric conductivity and magnetic permeability of a magnetic emulsion are no longer scalar coefficients, but are tensors. The electric conductivity and magnetic permeability tensors of sufficiently diluted emulsions in sufficiently weak electric and magnetic fields are found as functions of the electric and magnetic intensity vectors. The theoretically predicted induced anisotropy was verified experimentally. The experimental data are analyzed and compared with theoretical predictions. The results of the analysis and comparison are discussed.
Classical and Quantum Mechanics via Lie algebras
Arnold Neumaier; Dennis Westra
2011-04-14
The goal of this book is to present classical mechanics, quantum mechanics, and statistical mechanics in an almost completely algebraic setting, thereby introducing mathematicians, physicists, and engineers to the ideas relating classical and quantum mechanics with Lie algebras and Lie groups. The book emphasizes the closeness of classical and quantum mechanics, and the material is selected in a way to make this closeness as apparent as possible. Much of the material covered here is not part of standard textbook treatments of classical or quantum mechanics (or is only superficially treated there). For physics students who want to get a broader view of the subject, this book may therefore serve as a useful complement to standard treatments of quantum mechanics. Almost without exception, this book is about precise concepts and exact results in classical mechanics, quantum mechanics, and statistical mechanics. The structural properties of mechanics are discussed independent of computational techniques for obtaining quantitatively correct numbers from the assumptions made. The standard approximation machinery for calculating from first principles explicit thermodynamic properties of materials, or explicit cross sections for high energy experiments can be found in many textbooks and is not repeated here.
A. Rezaei-Aghdam; M. Sephid
2015-03-15
We obtain the classical r-matrices of real two and three dimensional Jacobi-Lie bialgebras. In this way, we classify all non-isomorphic real two and three dimensional coboundary Jacobi-Lie bialgebras and their types (triangular and quasitriangular). Also, we obtain the generalized Sklyanin bracket formula and then using it, we calculate the Jacobi structures on the related Jacobi-Lie groups. Finally, we present a new method for constructing classical integrable systems using coboundary Jacobi-Lie bialgebras.
Nature of Electric and Magnetic Fields; How the Fields Transform
Ivezic, Tomislav
2015-01-01
In this paper the proofs are given that the electric and magnetic fields are properly defined vectors on the four-dimensional (4D) spacetime (the 4-vectors in the usual notation) and not the usual 3D fields. Furthermore, the proofs are presented that under the mathematically correct Lorentz transformations (LT), e.g., the electric field vector transforms as any other vector transforms, i.e., again to the electric field vector; there is no mixing with the magnetic field vector B, as in the usual transformations (UT) of the 3D fields. The derivations of the UT from some well-known textbooks are discussed and objected.
Nature of Electric and Magnetic Fields; How the Fields Transform
Tomislav Ivezic
2015-08-10
In this paper the proofs are given that the electric and magnetic fields are properly defined vectors on the four-dimensional (4D) spacetime (the 4-vectors in the usual notation) and not the usual 3D fields. Furthermore, the proofs are presented that under the mathematically correct Lorentz transformations (LT), e.g., the electric field vector transforms as any other vector transforms, i.e., again to the electric field vector; there is no mixing with the magnetic field vector B, as in the usual transformations (UT) of the 3D fields. The derivations of the UT from some well-known textbooks are discussed and objected.
Polytope expansion of Lie characters and applications
Walton, Mark A., E-mail: walton@uleth.ca [Department of Physics and Astronomy, University of Lethbridge, Lethbridge, Alberta T1K 3M4 (Canada)
2013-12-15
The weight systems of finite-dimensional representations of complex, simple Lie algebras exhibit patterns beyond Weyl-group symmetry. These patterns occur because weight systems can be decomposed into lattice polytopes in a natural way. Since lattice polytopes are relatively simple, this decomposition is useful, in addition to being more economical than the decomposition into single weights. An expansion of characters into polytope sums follows from the polytope decomposition of weight systems. We study this polytope expansion here. A new, general formula is given for the polytope sums involved. The combinatorics of the polytope expansion are analyzed; we point out that they are reduced from those of the Weyl character formula (described by the Kostant partition function) in an optimal way. We also show that the weight multiplicities can be found easily from the polytope multiplicities, indicating explicitly the equivalence of the two descriptions. Finally, we demonstrate the utility of the polytope expansion by showing how polytope multiplicities can be used in the calculation of tensor product decompositions, and subalgebra branching rules.
Constraining primordial vector mode from B-mode polarization
Saga, Shohei; Ichiki, Kiyotomo; Shiraishi, Maresuke E-mail: maresuke.shiraishi@pd.infn.it
2014-10-01
The B-mode polarization spectrum of the Cosmic Microwave Background (CMB) may be the smoking gun of not only the primordial tensor mode but also of the primordial vector mode. If there exist nonzero vector-mode metric perturbations in the early Universe, they are known to be supported by anisotropic stress fluctuations of free-streaming particles such as neutrinos, and to create characteristic signatures on both the CMB temperature, E-mode, and B-mode polarization anisotropies. We place constraints on the properties of the primordial vector mode characterized by the vector-to-scalar ratio r{sub v} and the spectral index n{sub v} of the vector-shear power spectrum, from the Planck and BICEP2 B-mode data. We find that, for scale-invariant initial spectra, the ?CDM model including the vector mode fits the data better than the model including the tensor mode. The difference in ?{sup 2} between the vector and tensor models is ??{sup 2} = 3.294, because, on large scales the vector mode generates smaller temperature fluctuations than the tensor mode, which is preferred for the data. In contrast, the tensor mode can fit the data set equally well if we allow a significantly blue-tilted spectrum. We find that the best-fitting tensor mode has a large blue tilt and leads to an indistinct reionization bump on larger angular scales. The slightly red-tilted vector mode supported by the current data set can also create O(10{sup -22})-Gauss magnetic fields at cosmological recombination. Our constraints should motivate research that considers models of the early Universe that involve the vector mode.
MOTION CONTROL FOR UNDERACTUATED MECHANICAL SYSTEMS ON LIE GROUPS
Leonard, Naomi
MOTION CONTROL FOR UNDERACTUATED MECHANICAL SYSTEMS ON LIE GROUPS Francesco Bullo Control controlla bility, underactuated systems Abstract Control design for underactuated mechanical systems is an active area of research. In this paper we focus on mechanical control systems defined on Lie groups
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.
ccsd-00001485,version1-26Apr2004 On the Lie envelopping algebra of a pre-Lie algebra
Boyer, Edmond
ccsd-00001485,version1-26Apr2004 On the Lie envelopping algebra of a pre-Lie algebra J.-M. Oudom combinatorics Hopf algebras were introduced in different settings. One can quote the Hopf algebras of C. Brouder that a lot of these Hopf algebras are related to general algebraic constructions. In the commutative (or
Krawtchouk polynomials, the Lie algebra $\\mathfrak{sl}_2$, and Leonard pairs
Nomura, Kazumasa
2012-01-01
A Leonard pair is a pair of diagonalizable linear transformations of a finite-dimensional vector space, each of which acts in an irreducible tridiagonal fashion on an eigenbasis for the other one. In the present paper we give an elementary but comprehensive account of how the following are related: (i) Krawtchouk polynomials; (ii) finite-dimensional irreducible modules for the Lie algebra ${\\mathfrak{sl}_2}$; (iii) a class of Leonard pairs said to have Krawtchouk type. Along the way we obtain elementary proofs of some well-known facts about Krawtchouk polynomials, such as the three-term recurrence, the orthogonality, the difference equation, and the generating function. The paper is a tutorial meant for a graduate student or a researcher unfamiliar with the above topics.
DIPLOMA THESIS VECTOR ANTENNA FOR
Considerations 17 3.8 Ultra HighEnergy Cosmic Neutrino (UHEC) Antanna 17 4 Mechanical Construction 19 4 for a 3D object 21 5 Vector Antenna performance 35 5.1 Electrical Properties of the Antenna Medium or Environment 35 5.1.1 Electromagnetic Wave in Ice 35 5.2 UHEC Antenna Amplification 35 5.3 Vector Measurements
On Lie algebra extensions in a symplectic framework Javier Fernandeza)
Fernandez, Javier
On Lie algebra extensions in a symplectic framework Javier Fernandeza) Departamento de MatemaÂ´tica de MatemaÂ´tica--Facultad de Ciencias Exactas, Universidad Nacional de La Plata, 1900--La Plata
The effects of lying on lexical entrainment in dialogue
Tosi, Alessia
2012-11-28
entrainment). In this study, I developed an experimental paradigm with pairs of naive participants with the aim to investigate how lying affects lexical entrainment and impacts interlocutors' linguistic performances in terms of duration of dialogue and liars...
Low-lying Gamow-Teller transitions in spherical nuclei
Cakmak, N.; Uenlue, S.; Selam, C.
2012-01-15
The Pyatov Method has been used to study the low-lying Gamow-Teller transitions in the mass region of 98 Less-Than-Or-Slanted-Equal-To A Less-Than-Or-Slanted-Equal-To 130. The eigenvalues and eigenfunctions of the total Hamiltonian have been solved within the framework of proton-neutron quasiparticle random-phase approximation. The low-lying {beta} decay log(ft) values have been calculated for the nuclei under consideration.
Breaking classical Lie groups to finite subgroups - an automated approach
Maximilian Fallbacher
2015-07-15
The decomposition of representations of compact classical Lie groups into representations of finite subgroups is discussed. A Mathematica package is presented that can be used to compute these branching rules using the Weyl character formula. For some low order finite groups including $A_4$ and $\\Delta(27)$ general analytical formulas are presented for the branching rules of arbitrary representations of their smallest Lie super-groups.
Breaking classical Lie groups to finite subgroups - an automated approach
Fallbacher, Maximilian
2015-01-01
The decomposition of representations of compact classical Lie groups into representations of finite subgroups is discussed. A Mathematica package is presented that can be used to compute these branching rules using the Weyl character formula. For some low order finite groups including $A_4$ and $\\Delta(27)$ general analytical formulas are presented for the branching rules of arbitrary representations of their smallest Lie super-groups.
Thomas Hambye
2010-03-16
We show that dark matter could be made of massive gauge bosons whose stability doesn't require to impose by hand any discrete or global symmetry. Stability of gauge bosons can be guaranteed by the custodial symmetry associated to the gauge symmetry and particle content of the model. The particle content we consider to this end is based on a hidden sector made of a vector multiplet associated to a non-abelian gauge group and of a scalar multiplet charged under this gauge group. The hidden sector interacts with the Standard Model particles through the Higgs portal quartic scalar interaction in such a way that the gauge bosons behave as thermal WIMPS. This can lead easily to the observed dark matter relic density in agreement with the other various constraints, and can be tested experimentally in a large fraction of the parameter space. In this model the dark matter direct detection rate and the annihilation cross section can decouple if the Higgs portal interaction is weak.
Magnetic-Surface Quality in Nonaxisymmetric Plasma Equilibria Carolin Nuhrenberg*
Hudson, Stuart
received 21 January 2009; published 9 June 2009) The confinement of plasmas by magnetic fields A central requirement in magnetic confinement fusion is to balance the pressure force with the Lorentz force gradient is nonzero, both the magnetic field B and the current density j must lie on the constant pressure
Introducing light vector and axial vector mesons in the union of chiral and heavy quark symmetries
Kamal, A.N.; Xu, Q.P. (Theoretical Physics Institute and Department of Physics, University of Alberta, Edmonton, Alberta, T6G 2J1 (Canada))
1994-02-01
We introduce light vector and axial vector mesons as gauge particles in a (broken) local SU[sub [ital L
247VECTORIZING THE COMMUNITY LAND MODEL VECTORIZING THE COMMUNITY
Hoffman, Forrest M.
systems models (including the CLM) on vector architectures. However, the prior development of the CLM in Japan and the Cray X1 at Oak Ridge National Laboratory (ORNL) spawned renewed interest in running Earth
PRETEX (Halifax NS) #1 1054 1999 Mar 05 10:59:16
2010-02-12
Feb 16, 2007 ... if V is the set of all 2 × 2 matrices, then the vectors in V are 2 × 2 ... complex elements and F denotes the set of all complex numbers, then the ...
Classification of generalized quantum statistics associated with the exceptional Lie (super)algebras
Stoilova, N. I.; Jeugt, J. van der
2007-04-15
Generalized quantum statistics (GQS) associated with a Lie algebra or Lie superalgebra extends the notion of para-Bose or para-Fermi statistics. Such GQS have been classified for all classical simple Lie algebras and basic classical Lie superalgebras. In the current paper we finalize this classification for all exceptional Lie algebras and superalgebras. Since the definition of GQS is closely related to a certain Z grading of the Lie (super)algebra G, our classification reproduces some known Z gradings of exceptional Lie algebras. For exceptional Lie superalgebras such a classification of Z gradings has not been given before.
Magnetic Wells in Dimension Three
Bernard Helffer; Yuri Kordyukov; Nicolas Raymond; San Vu Ngoc
2015-05-13
This paper deals with semiclassical asymptotics of the three-dimensional magnetic Laplacian in presence of magnetic confinement. Using generic assumptions on the geometry of the confinement, we exhibit three semiclassical scales and their corresponding effective quantum Hamiltonians, by means of three microlocal normal forms \\`a la Birkhoff. As a consequence, when the magnetic field admits a unique and non degenerate minimum, we are able to reduce the spectral analysis of the low-lying eigenvalues to a one-dimensional $\\hbar$-pseudo-differential operator whose Weyl's symbol admits an asymptotic expansion in powers of $\\hbar^{\\frac1 2}$.
Motion on Lie groups and its applications in Control Theory
José F. Cariñena; Jesús Clemente-Gallardo; Arturo Ramos
2003-07-01
The usefulness in control theory of the geometric theory of motion on Lie groups and homogeneous spaces will be shown. We quickly review some recent results concerning two methods to deal with these systems, namely, a generalization of the method proposed by Wei and Norman for linear systems, and a reduction procedure. This last method allows us to reduce the equation on a Lie group $G$ to that on a subgroup $H$, provided a particular solution of an associated problem in $G/H$ is known. These methods are shown to be very appropriate to deal with control systems on Lie groups and homogeneous spaces, through the specific examples of the planar rigid body with two oscillators and the front-wheel driven kinematic car.
Electric-magnetic duality implies (global) conformal invariance
Sung-Pil Moon; Sang-Jin Lee; Ji-Hye Lee; Jae-Hyuk Oh
2014-05-30
We have examined quantum theories of electric magnetic duality invariant vector fields enjoying classical conformal invariance in 4-dimensional flat spacetime. We extend Dirac's argument about "the conditions for a quantum field theory to be relativistic" to "those for a quantum theory to be conformal". We realize that electric magnetic duality invariant vector theories together with classical conformal invariance defined in 4-$d$ flat spacetime are still conformally invariant theories when they are quantized in a way that electric magnetic duality is manifest.
Tadesse, Tilaye; Alexei, Pevtsov A; Macneice, P; Gosain, S
2013-01-01
Solar eruptive phenomena, like flares and coronal mass ejections(CMEs) are governed by magnetic fields. To describe the structure of these phenomena one needs information on the magnetic flux density and the electric current density vector components in three dimensions throughout the atmosphere. However, current spectro-polarimetric measurements typically limit the determination of the vector magnetic field only to the photosphere. Therefore, there is considerable interest in accurate modeling of the solar coronal magnetic field using photospheric vector magnetograms as boundary data. In this work, we model the coronal magnetic field for global solar atmosphere using a nonlinear force-free field(NLFFF) extrapolation codes implemented to a synoptic maps of photospheric vector magnetic field synthesized from Vector Spectromagnetograph (VSM) on Synoptic Optical Long-term Investigations of the Sun (SOLIS) as boundary condition. Using the resulting three dimensional magnetic field, we calculate the three dimensio...
Lie Groupoids in Classical Field Theory I: Noether's Theorem
Costa, Bruno T; Pêgas, Luiz Henrique P
2015-01-01
In the two papers of this series, we initiate the development of a new approach to implementing the concept of symmetry in classical field theory, based on replacing Lie groups/algebras by Lie groupoids/algebroids, which are the appropriate mathematical tools to describe local symmetries when gauge transformations are combined with space-time transformations. Here, we outline the basis of the program and, as a first step, show how to (re)formulate Noether's theorem about the connection between symmetries and conservation laws in this approach.
Temnov, Vasily V.
The magnetic field is an interesting candidate for the development of active plasmonic devices as it is able to modify the surface plasmon polariton (SPP) wave vector. Both real and imaginary parts of the SPP wave vector ...
Low-Lying Eigenvalues of the Wilson-Dirac Operator
K. Jansen; C. Liu; H. Simma; D. Smith
1996-08-09
An exploratory study of the low-lying eigenvalues of the Wilson-Dirac operator and their corresonding eigenvectors is presented. Results for the eigenvalues from quenched and unquenched simulations are discussed. The eigenvectors are studied with respect to their localization properties in the quenched approximation for the cases of SU(2) and SU(3).
The pre-Lie operad as a deformation of NAP
Saidi, Abdellatif
2010-01-01
We define a family of multigraded operads $O_\\lambda$ depending on a scalar parameter, such that forgetting the multigraduation gives back the pre-Lie operad when the parameter $\\lambda$ is equal to one, and the NAP operad governing Non-Associative Permutative algebras when $\\lambda$ is equal to zero.
Exceptional Lie Groups, E-infinity Theory and Higgs Boson
Ayman A. El-Okaby
2007-12-30
In this paper, we study the correlation between the exceptional lie groups and El-Naschie's transfinite E-infinity spacetime theory. Subsequently this is used to calculate the number of elementary particles in the standard model, mass of the Higgs boson and some coupling constants.
General properties of the expansion methods of Lie algebras
Laura Andrianopoli; Nelson Merino; Felip Nadal; Mario Trigiante
2013-08-22
The study of the relation between Lie algebras and groups, and especially the derivation of new algebras from them, is a problem of great interest in mathematics and physics, because finding a new Lie group from an already known one also means that a new physical theory can be obtained from a known one. One of the procedures that allow to do so is called expansion of Lie algebras, and has been recently used in different physical applications - particularly in gauge theories of gravity. Here we report on further developments of this method, required to understand in a deeper way their consequences in physical theories. We have found theorems related to the preservation of some properties of the algebras under expansions that can be used as criteria and, more specifically, as necessary conditions to know if two arbitrary Lie algebras can be related by the some expansion mechanism. Formal aspects, such as the Cartan decomposition of the expanded algebras, are also discussed. Finally, an instructive example that allows to check explicitly all our theoretical results is also provided.
VERY BASIC LIE THEORY Department of Mathematics, Yale University, New Haven, CT 06520
Berenstein, Arkady
VERY BASIC LIE THEORY ROGER HOWE Department of Mathematics, Yale University, New Haven, CT 06520 Lie theory, the theory of Lie groups, Lie algebras and their applications, is a fundamental part variables), group and ring theory, number theory, and physics, from classical to quantum and relativistic
Jose Beltran Jimenez; Antonio L. Maroto
2008-07-16
We explore the possibility that the present stage of accelerated expansion of the universe is due to the presence of a cosmic vector field. We show that vector theories allow for the generation of an accelerated phase without the introduction of potential terms or unnatural scales in the Lagrangian. We propose a particular model with the same number of parameters as LCDM and excellent fits to SNIa data. The model is scaling during radiation era, with natural initial conditions, thus avoiding the cosmic coincidence problem. Upcoming observations will be able to clearly discriminate it from standard LCDM cosmology
A Universal Magnetic Helicity Integral
Gunnar Hornig
2006-06-28
A magnetic helicity integral is proposed which can be applied to domains which are not magnetically closed, i.e. have a non-vanishing normal component of the magnetic field on the boundary. In contrast to the relative helicity integral, which was previously suggested for magnetically open domains, it does not rely on a reference field and thus avoids all problems related to the choice of a particular reference field. Instead it uses a gauge condition on the vector potential, which corresponds to a particular topologically unique closure of the magnetic field in the external space. The integral has additional elegant properties and is easy to compute numerically in practice. For magnetically closed domains it reduces to the classical helicity integral.
2.6 ELECTRIC AND MAGNETIC FIELDS Introduction
California at Santa Cruz, University of
325 Â§2.6 ELECTRIC AND MAGNETIC FIELDS Introduction In electromagnetic theory the mks system MKS units Replacement symbol GAUSSIAN units # E (Electric field) volt/m # E statvolt/cm # B (Magnetic Magnetic field) ampere/m c # H 4# oersted # J (Current density) ampere/m 2 # J statampere/cm 2 # A (Vector
Lorentz and "apparent" transformations of the electric and magnetic fields
Tomislav Ivezic
2006-07-21
It is recently discovered that the usual transformations of the three-dimensional (3D) vectors of the electric and magnetic fields differ from the Lorentz transformations (LT) (boosts) of the corresponding 4D quantities that represent the electric and magnetic fields. In this paper, using geometric algebra formalism, this fundamental difference is examined representing the electric and magnetic fields by bivectors.
Distribution Amplitudes of Vector Mesons
V. M. Braun; D. Brömmel; M. Göckeler; R. Horsley; Y. Nakamura; H. Perlt; D. Pleiter; P. E. L. Rakow; A. Schäfer; G. Schierholz; A. Schiller; W. Schroers; T. Streuer; H. Stüben; J. M. Zanotti
2007-11-14
Results are presented for the lowest moment of the distribution amplitude for the K-star vector meson. Both longitudinal and transverse moments are investigated. We use two flavours of O(a) improved Wilson fermions, together with a non-perturbative renormalisation of the matrix element.
Kinematical versus Dynamical Contractions of the de Sitter Lie algebras
Joachim Nzotungicimpaye
2015-07-13
We explicit and clarify better the contraction method that Bacry and Levy-Leblond\\cite{jmll} used to link all the kinematical Lie groups. Firstly, we use the kinematical parameters: the speed $c$ of light, the radius $r$ of the universe and the period $\\tau$ of the universe constrained by $r=c\\tau$. Secondly, we use the dynamical parameters that are mass $m$, energy $E_0$ and compliance $C$. The kinematical and the dynamical parameters are related by the three relations $c^2=\\frac{E_0}{m}$, $\\tau^2=mC$ and $r^2=CE_0$. For each kinematical Lie algebra, we express the associated physical quantities in function of these dynamical parameters.
Measurement of the somatosensory magnetic evoked potential
Pashkoff, Benjamin Lewis
1983-01-01
and the element, and the direction of movement of j (see figure 1). The -7 constant, s0, the permeability of free space, is 4s*10 Tesla- meter/ampere. The total magnetic field is the vector sum of these separate elements. Any magnetic field with a source... of the surrounding magnetic noise is greater than the amplitude of the signal from the brain by many orders of magnitude. The steady -4 magnetic field of the Earth is on the order of 1~10 Tesla (T), while the average amplitude of the magnetic field of the brain...
Flavor twisted boundary conditions and the nucleon vector current
Jiang, F.-J.; Tiburzi, B. C.
2008-12-01
Using flavor twisted boundary conditions, we study nucleon matrix elements of the vector current. We twist only the active quarks that couple to the current. Finite volume corrections due to twisted boundary conditions are determined using partially twisted, partially quenched, heavy baryon chiral perturbation theory, which we develop for the graded group SU(7|5). Asymptotically these corrections are exponentially small in the volume, but can become pronounced for small twist angles. Utilizing the Breit frame does not mitigate volume corrections to nucleon vector current matrix elements. The derived expressions will allow for better controlled extractions of the isovector magnetic moment and the electromagnetic radii from simulations at zero lattice momentum. Our formalism, moreover, can be applied to any nucleon matrix elements.
Linear Regression and Support Vector Regression
Shi, Qinfeng "Javen"
Linear Regression and Support Vector Regression Paul Paisitkriangkrai paulp@cs.adelaide.edu.au The University of Adelaide 18 August 2014 #12;Outlines · Regression overview · Linear regression · Support vector regression · Machine learning tools available #12;Regression Overview CLUSTERING CLASSIFICATION REGRESSION
Vector-thread architecture and implementation
Krashinsky, Ronny (Ronny Meir), 1978-
2007-01-01
This thesis proposes vector-thread architectures as a performance-efficient solution for all-purpose computing. The VT architectural paradigm unifies the vector and multithreaded compute models. VT provides the programmer ...
Egedal, Jan
on a global scale.1,2 By way of example, reconnection controls the evolution of solar flares,3 allows vector potential, A . From the measured A , the magnetic field geometry, current density the solar wind to enter the Earth's magnetosphere,4 and is an integral part of magnetic substorms observed
Classification of prostate magnetic resonance spectra using support vector machine
Paris-Sud XI, Université de
to Biomedical Signal Processing and Control December 12, 2011 hal-00650862,version1-12Dec2011 Author manuscript, published in "Biomedical Signal Processing and Control (2011) 1-8" DOI : 10.1016/j.bspc.2011.09.003 #12;pre-processed- tomatic classification with and without quantification of metabolite signals. The dataset is composed
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -Using supercriticalWeatherize Â» Moisture
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservationBio-Inspired SolarAbout /Two0 -Using supercriticalWeatherize Â» MoistureRunning jobs
Utah, University of
Breslau ¶ Princeton Plasma Physics Laboratory Abstract-- In the development of magnetic confinement fusion patterns 1 INTRODUCTION The development of magnetic confinement fusion which will poten- tially be a future the magnetic field that confines the burning plasma. While the magnetic field can be described as a vector
Bret, A., E-mail: antoineclaude.bret@uclm.es [ETSI Industriales, Universidad de Castilla-La Mancha, 13071 Ciudad Real, Spain and Instituto de Investigaciones Energéticas y Aplicaciones Industriales, Campus Universitario de Ciudad Real, 13071 Ciudad Real (Spain)
2014-02-15
The filamentation (Weibel) instability plays a key role in the formation of collisionless shocks which are thought to produce Gamma-Ray-Bursts and High-Energy-Cosmic-Rays in astrophysical environments. While it has been known for long that a flow-aligned magnetic field can completely quench the instability, it was recently proved in 2D that in the cold regime, such cancelation is possible if and only if the field is perfectly aligned. Here, this result is finally extended to a 3D geometry. Calculations are conducted for symmetric and asymmetric counter-streaming relativistic plasma shells. 2D results are retrieved in 3D: the instability can never be completely canceled for an oblique magnetic field. In addition, the maximum growth-rate is always larger for wave vectors lying in the plan defined by the flow and the oblique field. On the one hand, this bears consequences on the orientation of the generated filaments. On the other hand, it certifies 2D simulations of the problem can be performed without missing the most unstable filamentation modes.
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.
The Hopf algebra of Fliess operators and its dual pre-Lie Loc Foissy
Paris-Sud XI, Université de
The Hopf algebra of Fliess operators and its dual pre-Lie algebra Loïc Foissy Laboratoire de.foissy@univ-reims.fr ABSTRACT. We study the Hopf algebra H of Fliess operators coming from Control Theory in the one space R x0, x1 is both a pre-Lie algebra for the pre-Lie product dual of the coproduct of H
Kinematics in Vector Boson Fusion
D. Green
2006-03-02
The vector boson fusion process leads to two forward/backward jets (tag jets) and the produced state, a Higgs boson in this case, moving slowly in the p-p C.M. frame at the LHC. For the case of Higgs decaying to W+W (W*) with Higgs mass below 180 GeV, the W bosons have low momentum in the Higgs C.M. For the case of W leptonic decays, this fact allows for an approximate reconstruction of the two final state neutrinos. In turn, those solutions then provide additional kinematic cuts against background.
Thermomagnetic burn control for magnetic fusion reactor
Rawls, John M. (Del Mar, CA); Peuron, Unto A. (Solana Beach, CA)
1982-01-01
Apparatus is provided for controlling the plasma energy production rate of a magnetic-confinement fusion reactor, by controlling the magnetic field ripple. The apparatus includes a group of shield sectors (30a, 30b, etc.) formed of ferromagnetic material which has a temperature-dependent saturation magnetization, with each shield lying between the plasma (12) and a toroidal field coil (18). A mechanism (60) for controlling the temperature of the magnetic shields, as by controlling the flow of cooling water therethrough, thereby controls the saturation magnetization of the shields and therefore the amount of ripple in the magnetic field that confines the plasma, to thereby control the amount of heat loss from the plasma. This heat loss in turn determines the plasma state and thus the rate of energy production.
Thermomagnetic burn control for magnetic fusion reactor
Rawls, J.M.; Peuron, A.U.
1980-07-01
Apparatus is provided for controlling the plasma energy production rate of a magnetic-confinement fusion reactor, by controlling the magnetic field ripple. The apparatus includes a group of shield sectors formed of ferromagnetic material which has a temperature-dependent saturation magnetization, with each shield lying between the plasma and a toroidal field coil. A mechanism for controlling the temperature of the magnetic shields, as by controlling the flow of cooling water therethrough, thereby controls the saturation magnetization of the shields and therefore the amount of ripple in the magnetic field that confines the plasma, to thereby control the amount of heat loss from the plasma. This heat loss in turn determines the plasma state and thus the rate of energy production.
Reconfigurable multipipelines for vector supercomputers
Gupta, R. . Dept. of Electrical Engineering); Zorat, A. ); Ramakrishnan, I.V. . Dept. of Computer Science)
1989-09-01
Supercomputers typically use pipelines in their processors for achieving high performance. These pipelines consist of several stages and many such identical pipelines are used in vector supercomputers for doing vector operations. This paper addresses the problem of recovering multipipelines in the presence of faulty stages. The stages are assumed to be organized in rows and columns. The authors alternate the pipeline stages with reconfiguring circuitry which is used for bypassing the faulty stages. The pipelines are configured by programming the switches in a distributed manner using fault information available locally. The reprogrammability of the switches enables them to tolerate dynamic faults. Their configuration algorithm is optimal in the sense that it recovers the maximum number of pipelines under any fault pattern. Probabilistic bounds on the delay (the number of bypassed faulty stages) and yield (the number of nonfaulty pipelines recovered) are derived. They show that the maximum signal delay in any of the pipelines is {theta}(logm), where m is the initial number of pipelines.
A Vector-Like Fourth Generation with A Discrete Symmetry From Split-UED
Kong, Kyoungchul; /SLAC; Park, Seong Chan; /Tokyo U., IPMU; Rizzo, Thomas G.; /SLAC
2011-08-19
Split-UED allows for the possibility that the lowest lying KK excitations of the Standard Model fermions can be much lighter than the corresponding gauge or Higgs KK states. This can happen provided the fermion bulk masses are chosen to be large, in units of the inverse compactification radius, 1/R, and negative. In this setup, all of the other KK states would be effectively decoupled from low energy physics. Such a scenario would then lead to an apparent vector-like fourth generation with an associated discrete symmetry that allows us to accommodate a dark matter candidate. In this paper the rather unique phenomenology presented by this picture will be examined.
He I VECTOR MAGNETOMETRY OF FIELD-ALIGNED SUPERPENUMBRAL FIBRILS
Schad, T. A. [Department of Planetary Sciences, University of Arizona, Tucson, AZ 85721 (United States); Penn, M. J. [National Solar Observatory, Tucson, AZ 85719 (United States); Lin, H. [Institute for Astronomy, University of Hawaii, Pukalani, HI 96768 (United States)
2013-05-10
Atomic-level polarization and Zeeman effect diagnostics in the neutral helium triplet at 10830 A in principle allow full vector magnetometry of fine-scaled chromospheric fibrils. We present high-resolution spectropolarimetric observations of superpenumbral fibrils in the He I triplet with sufficient polarimetric sensitivity to infer their full magnetic field geometry. He I observations from the Facility Infrared Spectropolarimeter are paired with high-resolution observations of the H{alpha} 6563 A and Ca II 8542 A spectral lines from the Interferometric Bidimensional Spectrometer from the Dunn Solar Telescope in New Mexico. Linear and circular polarization signatures in the He I triplet are measured and described, as well as analyzed with the advanced inversion capability of the ''Hanle and Zeeman Light'' modeling code. Our analysis provides direct evidence for the often assumed field alignment of fibril structures. The projected angle of the fibrils and the inferred magnetic field geometry align within an error of {+-}10 Degree-Sign . We describe changes in the inclination angle of these features that reflect their connectivity with the photospheric magnetic field. Evidence for an accelerated flow ({approx}40 m s{sup -2}) along an individual fibril anchored at its endpoints in the strong sunspot and weaker plage in part supports the magnetic siphon flow mechanism's role in the inverse Evershed effect. However, the connectivity of the outer endpoint of many of the fibrils cannot be established.
Invariants and labels for Lie-Poisson Systems
Thiffeault, J.L.; Morrison, P.J.
1998-04-01
Reduction is a process that uses symmetry to lower the order of a Hamiltonian system. The new variables in the reduced picture are often not canonical: there are no clear variables representing positions and momenta, and the Poisson bracket obtained is not of the canonical type. Specifically, we give two examples that give rise to brackets of the noncanonical Lie-Poisson form: the rigid body and the two-dimensional ideal fluid. From these simple cases, we then use the semidirect product extension of algebras to describe more complex physical systems. The Casimir invariants in these systems are examined, and some are shown to be linked to the recovery of information about the configuration of the system. We discuss a case in which the extension is not a semidirect product, namely compressible reduced MHD, and find for this case that the Casimir invariants lend partial information about the configuration of the system.
1.1 Vector and integral identities
2011-08-23
In this section we list some notation, vector and integral identities that are com- monly used in the finite element formulation of the boundary-value problems in.
On the health of a vector field with (R A^2)/6 coupling to gravity
Mindaugas Kar?iauskas; David Lyth
2010-07-08
The coupling (R A^2)/6 of a vector field to gravity was proposed as a mechanism for generating a primordial magnetic field, and more recently as a mechanism for generating a statistically anisotropic contribution to the primordial curvature perturbation. In either case, the vector field's perturbation has both a transverse and a longitudinal component, and the latter has some unusual features which call into question the health of the theory. We calculate for the first time the energy density generated by the longitudinal field perturbations, and go on to argue that the theory may well be healthy in at least some versions.
Introduction to vectors and tensors, Vol 2: vector and tensor analysis
Bowen, Ray M.; Wang, C.-C.
2006-06-20
This is the second volume of a two-volume work on vectors and tensors. Volume 1 is concerned with the algebra of vectors and tensors, while this volume is concerned with the geometrical aspects of vectors and tensors. This volume begins with a...
DAMAGE LOCALIZATION USING LOAD VECTORS Dionisio Bernal
Bernal, Dionisio
DAMAGE LOCALIZATION USING LOAD VECTORS Dionisio Bernal Associate Professor Department of Civil: A technique to localize damage in structures that can be treated as linear in the pre and post-damage state is presented. Central to the approach is the computation of a set of vectors, designated as Damage Locating
An Unbroken Axial Vector Current Conservation Law
Rasulkhozha S. Sharafiddinov
2015-05-28
The mass, energy and momentum of the neutrino of a true flavor have an axial-vector nature. As a consequence, the left-handed truly neutral neutrino in an axial-vector field of emission can be converted into a right-handed one and vice versa. This predicts the unidenticality of masses, energies and momenta of neutrinos of the different components. Recognizing such a difference in masses, energies, momenta and accepting that the left-handed axial-vector neutrino and the right-handed antineutrino of true neutrality refer to long-lived C-odd leptons, and the right-handed truly neutral neutrino and the left-handed axial-vector antineutrino are of short-lived fermions of C-oddity, we would write a new CP-even Dirac equation taking into account the flavor symmetrical axial-vector mass, energy and momentum matrices. Their presence explains the spontaneous mirror symmetry violation, confirming that an axial-vector current conservation law has never violated. They reflect the availability of a mirror Minkowski space in which a neutrino is characterized by left as well as by right space-time coordinates. Therefore, it is not surprising that whatever the main purposes experiments about a quasielastic axial-vector mass say in favor of an axial-vector mirror Minkowski space-time.
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
Solving Linearized Equations of the $N$-body Problem Using the Lie-integration Method
Andras Pal; Aron Suli
2007-07-23
Several integration schemes exits to solve the equations of motion of the $N$-body problem. The Lie-integration method is based on the idea to solve ordinary differential equations with Lie-series. In the 1980s this method was applied for the $N$-body problem by giving the recurrence formula for the calculation of the Lie-terms. The aim of this works is to present the recurrence formulae for the linearized equations of motion of $N$-body systems. We prove a lemma which greatly simplifies the derivation of the recurrence formulae for the linearized equations if the recurrence formulae for the equations of motions are known. The Lie-integrator is compared with other well-known methods. The optimal step size and order of the Lie-integrator are calculated. It is shown that a fine-tuned Lie-integrator can be 30%-40% faster than other integration methods.
Unique system of FE/PD for magneto-optical recording and magnetic switching devices
Liu, Chian Q. (Hinsdale, IL); Bader, Samuel D. (Oak Park, IL)
1992-01-01
A high density magneto-optical information storage medium utilizing the properties of an ultrathin iron film on a palladium substrate. The present invention comprises a magneto-optical medium capable of thermal and magnetic stability and capable of possessing a vertical orientation of the magnetization vector for the magnetic material. Data storage relies on the temperature dependence of the coercivity of the ultrathin film. Data retrieval derives from the Kerr effect which describes the direction of rotation of a plane of polarized light traversing the ultrathin magnetic material as a function of the orientation of the magnetization vector.
Confined Dirac Particles in Constant and Tilted Magnetic Field
Abdulaziz D. Alhaidari; Hocine Bahlouli; Ahmed Jellal
2012-02-23
We study the confinement of charged Dirac particles in 3+1 space-time due to the presence of a constant and tilted magnetic field. We focus on the nature of the solutions of the Dirac equation and on how they depend on the choice of vector potential that gives rise to the magnetic field. In particular, we select a "Landau gauge" such that the momentum is conserved along the direction of the vector potential yielding spinor wavefunctions, which are localized in the plane containing the magnetic field and normal to the vector potential. These wave functions are expressed in terms of the Hermite polynomials. We point out the relevance of these findings to the relativistic quantum Hall effect and compare with the results obtained for a constant magnetic field normal to the plane in 2+1 dimensions.
The Higgs mass derived from the U(3) Lie group
Ole L. Trinhammer; Henrik G. Bohr; Mogens Stibius Jensen
2015-07-07
The Higgs mass value is derived from a Hamiltonian on the Lie group U(3) where we relate strong and electroweak energy scales. The baryon states of nucleon and delta resonances originate in specific Bloch wave degrees of freedom coupled to a Higgs mechanism which also gives rise to the usual gauge boson masses. The derived Higgs mass is around 125 GeV. From the same Hamiltonian we derive the relative neutron to proton mass ratio and the N and Delta mass spectra. All compare rather well with the experimental values. We predict scarce neutral flavor baryon singlets that should be visible in scattering cross sections for negative pions on protons, in photoproduction on neutrons, in neutron diffraction dissociation experiments and in invariant mass spectra of protons and negative pions in B-decays. The fundamental predictions are based on just one length scale and the fine structure constant. More particular predictions rely also on the weak mixing angle and the up-down quark flavor mixing matrix element. With differential forms on the measure-scaled wavefunction, we could generate approximate parton distribution functions for the u and d valence quarks of the proton that compare well with established experimental analysis.
THE MAGNETIC ENERGY-HELICITY DIAGRAM OF SOLAR ACTIVE REGIONS
Tziotziou, Kostas; Georgoulis, Manolis K.; Raouafi, Nour-Eddine
2012-11-01
Using a recently proposed nonlinear force-free method designed for single-vector magnetograms of solar active regions, we calculate the instantaneous free magnetic energy and relative magnetic helicity budgets in 162 vector magnetograms corresponding to 42 different active regions. We find a statistically robust, monotonic correlation between the free magnetic energy and the relative magnetic helicity in the studied regions. This correlation implies that magnetic helicity, in addition to free magnetic energy, may be an essential ingredient for major solar eruptions. Eruptive active regions appear well segregated from non-eruptive ones in both free energy and relative helicity with major (at least M-class) flares occurring in active regions with free energy and relative helicity exceeding 4 Multiplication-Sign 10{sup 31} erg and 2 Multiplication-Sign 10{sup 42} Mx{sup 2}, respectively. The helicity threshold agrees well with estimates of the helicity contents of typical coronal mass ejections.
Hessian structures, Euler vector fields, and thermodynamics
M. Á. García-Ariza
2015-06-15
In this paper, it is shown that the underlying geometric structure of thermodynamics is formed by two elements. The first one is a degenerate Hessian structure distinguished by the fact that its potentials are extensive functions. A suitable coordinate-free definition of the latter is presented, relying on a particular vector field which is proposed to be the second ingredient of the geometric structure of thermodynamics. This vector has the form of an Euler vector in certain coordinate charts that somehow generalize those formed by internal energy or entropy and deformation coordinates in the spaces of equilibrium states of thermodynamic systems. Intensive functions and Legendre transforms are reviewed under this approach.
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.
2009-01-01
mosquitoes. A PL meeting at the Biology of Disease Vectors (as a tool in vector biology. Transformation of the vector ofelement. Insect Molecular Biology 10: 597–604. 11. Balter
Three dimensional stress vector sensor array and method therefor...
Office of Scientific and Technical Information (OSTI)
Three dimensional stress vector sensor array and method therefor Citation Details In-Document Search Title: Three dimensional stress vector sensor array and method therefor A...
TOPICS IN ALGEBRA -LIE ALGEBRAS AND THEIR REPRESENTATIONS AMAT 820 (7223)
Lenart, Cristian
. Important advances have been made since Lie's work, through a better understanding of the subtle interplay representations, which are the building blocks for the construction of all representations of a given group. The universal enveloping algebra. Induced modules. Irreducible modules for the semisimple Lie algebras
Nambu structures on four dimensional real Lie groups and related superintegrable systems
S. Farhang-Sardroodi; A. Rezaei-Aghdam; L. Sedghi-Ghadim
2015-06-07
We have determined all Nambu tensors (Nambu structures) of order four and three on four dimensional real Lie groups. Furthermore, we have obtained superintegrable systems by use of the Nambu structures of order four on some of these Lie groups as phase spaces with symmetry groups A4;8 and A4;10.
Sex, Lies and Cyber-crime Dinei Florncio and Cormac Herley
Herley, Cormac
Sex, Lies and Cyber-crime Surveys Dinei FlorÃªncio and Cormac Herley Microsoft Research, Redmond Â· Men claim between 3x and 9x more lifetime heterosexual partners than women. (Various sex surveys) #12 of estimate From 4998 respondents Billions FTC`06IDTheftSurvey #12;Sex and Lies Men Report 3-9x More Female
Abedi-Fardad, J.; Rezaei-Aghdam, A.; Haghighatdoost, Gh.
2014-05-15
We construct integrable and superintegrable Hamiltonian systems using the realizations of four dimensional real Lie algebras as a symmetry of the system with the phase space R{sup 4} and R{sup 6}. Furthermore, we construct some integrable and superintegrable Hamiltonian systems for which the symmetry Lie group is also the phase space of the system.
Acoustic vector-sensor array processing
Kitchens, Jonathan Paul
2010-01-01
Existing theory yields useful performance criteria and processing techniques for acoustic pressure-sensor arrays. Acoustic vector-sensor arrays, which measure particle velocity and pressure, offer significant potential but ...
Dark energy as a massive vector field
C. G. Boehmer; T. Harko
2007-01-11
We propose that the Universe is filled with a massive vector field, non-minimally coupled to gravitation. The field equations of the model are consistently derived and their application to cosmology is considered. The Friedmann equations acquire an extra dark-energy component, which is proportional to the mass of the vector particle. This leads to a late-time accelerated de Sitter type expansion. The free parameters of the model (gravitational coupling constants and initial value of the cosmological vector field) can be estimated by using the PPN solar system constraints. The mass of the cosmological massive vector particle, which may represent the main component of the Universe, is of the order of 10^-63 g.
Integrated optic vector-matrix multiplier
Watts, Michael R. (Albuquerque, NM)
2011-09-27
A vector-matrix multiplier is disclosed which uses N different wavelengths of light that are modulated with amplitudes representing elements of an N.times.1 vector and combined to form an input wavelength-division multiplexed (WDM) light stream. The input WDM light stream is split into N streamlets from which each wavelength of the light is individually coupled out and modulated for a second time using an input signal representing elements of an M.times.N matrix, and is then coupled into an output waveguide for each streamlet to form an output WDM light stream which is detected to generate a product of the vector and matrix. The vector-matrix multiplier can be formed as an integrated optical circuit using either waveguide amplitude modulators or ring resonator amplitude modulators.
Imaging vector fields using Line Integral Convolution
Cabral, B.; Leedom, L.C.
1993-03-01
Imaging vector fields has applications in science, art, image processing and special effects. An effective new approach is to use linear and curvilinear filtering techniques to locally blur textures along a vector field. This approach builds on several previous texture generation and filtering techniques. It is, however, unique because it is local, one-dimensional and independent of any predefined geometry or texture. The technique is general and capable of imaging arbitrary two- and three-dimensional vector fields. The local one-dimensional nature of the algorithm lends itself to highly parallel and efficient implementations. Furthermore, the curvilinear filter is capable of rendering detail on very intricate vector fields. Combining this technique with other rendering and image processing techniques -- like periodic motion filtering -- results in richly informative and striking images. The technique can also produce novel special effects.
Evolution of graphene mediated magnetic coupling between S. V. Ong, R. Robles, S. N. Khanna
Rodriguez, Roberto
nanostructures. Pure graphene is a zero band gap semiconductor where the Fermi energy lies at the intersectionEvolution of graphene mediated magnetic coupling between Fe-chains S. V. Ong, R. Robles, S. N, stability, and magnetic coupling of Fe-chains at the zigzag edges of graphene ribbons have been carried out
Poynting-vector based method for determining the bearing and location of electromagnetic sources
Simons, David J. (Modesto, CA); Carrigan, Charles R. (Tracy, CA); Harben, Philip E. (Livermore, CA); Kirkendall, Barry A. (Golden, CO); Schultz, Craig A. (Danville, CA)
2008-10-21
A method and apparatus is utilized to determine the bearing and/or location of sources, such as, alternating current (A.C.) generators and loads, power lines, transformers and/or radio-frequency (RF) transmitters, emitting electromagnetic-wave energy for which a Poynting-Vector can be defined. When both a source and field sensors (electric and magnetic) are static, a bearing to the electromagnetic source can be obtained. If a single set of electric (E) and magnetic (B) sensors are in motion, multiple measurements permit location of the source. The method can be extended to networks of sensors allowing determination of the location of both stationary and moving sources.
An Unbroken Axial Vector Current Conservation Law
Sharafiddinov, Rasulkhozha S
2015-01-01
The mass, energy and momentum of the neutrino of a true flavor have an axial-vector nature. As a consequence, the left-handed truly neutral neutrino in an axial-vector field of emission can be converted into a right-handed one and vice versa. This predicts the unidenticality of masses, energies and momenta of neutrinos of the different components. Recognizing such a difference in masses, energies, momenta and accepting that the left-handed axial-vector neutrino and the right-handed antineutrino of true neutrality refer to long-lived C-odd leptons, and the right-handed truly neutral neutrino and the left-handed axial-vector antineutrino are of short-lived fermions of C-oddity, we would write a new CP-even Dirac equation taking into account the flavor symmetrical axial-vector mass, energy and momentum matrices. Their presence explains the spontaneous mirror symmetry violation, confirming that an axial-vector current conservation law has never violated. They reflect the availability of a mirror Minkowski space i...
Huang, Su-Yun
Multiclass Support Vector Classification via Regression Multiclass Support Vector Classification via Regression Pei-Chun Chen peichun@stat.sinica.edu.tw Institute of Statistical Science Academia classification is considered and resolved through the mul- tiresponse linear regression approach. Scores are used
Maryland at College Park, University of
Bred vectors: theory andBred vectors: theory and applications in operationalapplications predictability (chaos) b) Stable systems are infinitely predictable TRUTH TRUTH FORECAST FORECAST a) Unstable of chaos (Lorenz, 1960s): a) Unstable systems have finite predictability (chaos) b) Stable systems
Low-lying dipole resonance in neutron-rich Ne isotopes
Kenichi Yoshida; Nguyen Van Giai
2008-02-12
Microscopic structure of the low-lying isovector dipole excitation mode in neutron-rich $^{26,28,30}$Ne is investigated by performing deformed quasiparticle-random-phase-approximation (QRPA) calculations. The particle-hole residual interaction is derived from a Skyrme force through a Landau-Migdal approximation. We have obtained the low-lying resonance in $^{26}$Ne at around 8.5 MeV. It is found that the isovector dipole strength at $E_{x}low-lying resonance is overlapping with the giant resonance.
Low-lying Dirac operator eigenvalues, lattice effects and random matrix theory
Urs M. Heller
2011-12-08
Recently, random matrix theory predictions for the distribution of low-lying Dirac operator eigenvalues have been extended to include lattice effects for both staggered and Wilson fermions. We computed low-lying eigenvalues for the Hermitian Wilson-Dirac operator and for improved staggered fermions on several quenched ensembles with size $\\approx 1.5$ fm. Comparisons to the expectations from RMT with lattice effects included are made. Wilson RMT describes our Wilson data nicely. For improved staggered fermions we find strong indications that taste breaking effects on the low-lying spectrum disappear in the continuum limit, as expected from staggered RMT.
Stability of Horndeski vector-tensor interactions
Jiménez, Jose Beltrán [Centre for Cosmology, Particle Physics and Phenomenology, Institute of Mathematics and Physics, Louvain University, 2 Chemin du Cyclotron, Louvain-la-Neuve, 1348 (Belgium); Durrer, Ruth; Heisenberg, Lavinia [Département de Physique Théorique and Center for Astroparticle Physics, Université de Genève, 24 quai Ansermet, Genève 4, CH-1211 (Switzerland); Thorsrud, Mikjel, E-mail: jose.beltran@uclouvain.be, E-mail: ruth.durrer@unige.ch, E-mail: lavinia.heisenberg@unige.ch, E-mail: mikjel.thorsrud@astro.uio.no [Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, Oslo, N-0315 (Norway)
2013-10-01
We study the Horndeski vector-tensor theory that leads to second order equations of motion and contains a non-minimally coupled abelian gauge vector field. This theory is remarkably simple and consists of only 2 terms for the vector field, namely: the standard Maxwell kinetic term and a coupling to the dual Riemann tensor. Furthermore, the vector sector respects the U(1) gauge symmetry and the theory contains only one free parameter, M{sup 2}, that controls the strength of the non-minimal coupling. We explore the theory in a de Sitter spacetime and study the presence of instabilities and show that it corresponds to an attractor solution in the presence of the vector field. We also investigate the cosmological evolution and stability of perturbations in a general FLRW spacetime. We find that a sufficient condition for the absence of ghosts is M{sup 2} > 0. Moreover, we study further constraints coming from imposing the absence of Laplacian instabilities. Finally, we study the stability of the theory in static and spherically symmetric backgrounds (in particular, Schwarzschild and Reissner-Nordström-de Sitter). We find that the theory, quite generally, do have ghosts or Laplacian instabilities in regions of spacetime where the non-minimal interaction dominates over the Maxwell term. We also calculate the propagation speed in these spacetimes and show that superluminality is a quite generic phenomenon in this theory.
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.
Role of the mean curvature in the geometry of magnetic confinement configurations
Skovoroda, A. A. [Russian Research Centre Kurchatov Institute (Russian Federation); Taimanov, I. A. [Russian Academy of Sciences, Sobolev Institute of Mathematics, Siberian Branch (Russian Federation)
2010-09-15
Examples are presented of how the geometric notion of the mean curvature is applied to the vector of a general magnetic field and to magnetic surfaces. It is shown that the mean curvature is related to the variation of the absolute value of the magnetic field along its lines. Magnetic surfaces of constant mean curvature are optimum for plasma confinement in multimirror open confinement systems and rippled tori.
Covariant Lyapunov vectors for rigid disk systems
Hadrien Bosetti; Harald A. Posch
2010-06-30
We carry out extensive computer simulations to study the Lyapunov instability of a two-dimensional hard disk system in a rectangular box with periodic boundary conditions. The system is large enough to allow the formation of Lyapunov modes parallel to the x axis of the box. The Oseledec splitting into covariant subspaces of the tangent space is considered by computing the full set of covariant perturbation vectors co-moving with the flow in tangent-space. These vectors are shown to be transversal, but generally not orthogonal to each other. Only the angle between covariant vectors associated with immediate adjacent Lyapunov exponents in the Lyapunov spectrum may become small, but the probability of this angle to vanish approaches zero. The stable and unstable manifolds are transverse to each other and the system is hyperbolic.
On the gauge features of gravity on a Lie algebroid structure
Fabi, S. Harms, B. Hou, S.
2014-03-15
We present the geometric formulation of gravity based on the mathematical structure of a Lie Algebroid. We show that this framework provides the geometrical setting to describe the gauge propriety of gravity.
Low-lying resonances of Be9Lambda : Faddeev calculation with Pade-approximants
I. Filikhin; V. M. Suslov; B. Vlahovic
2006-10-25
Configuration space Faddeev equations are applied to describe the Be9Lambda low-lying resonances of the ground band in the alpha+alpha+Lambda cluster model. The method of analytical continuation in coupling constant is used.
High-lying collective rotational states in Ba nuclei: Search for Jacobi Shapes.
Benzoni, Giovanna
High-lying collective rotational states in Ba nuclei: Search for Jacobi Shapes. G.Benzoni1 , A as a function of spin and compared with the liquid drop predictions including the Jacobi phase transition. 1
E. Paal; J. Virkepu
2010-02-14
Operadic Lax representations for the harmonic oscillator are used to construct the quantum counterparts of three-dimensional real Lie algebras. The Jacobi operators of these quantum algebras are explicitly calculated.
Quiz 5 solutions, Section ALL (10 pts.) If (0, 0, c) lies on the tangent ...
jony2_000
2014-10-07
Quiz 5 solutions, Section ALL. (10 pts.) If (0, 0, c) lies on the tangent plane to the surface z = x2. b y. 3 at (2, 1, 3), find c. Solution. We basically need to know ...
UNIVERSITY OF CALIFORNIA, SAN DIEGO Hypoelliptic heat kernel inequalities on Lie groups
Driver, Bruce
in Mathematics by Tai Alexis Melcher Committee in charge: Professor Bruce Driver, Chair Professor Peter Ebenfelt . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 4.2.1 Stratified nilpotent Lie groups . . . . . . . . . . . . . . . . . . . . 92 4.2.2 Nilpotent
Higgsed Stueckelberg Vector and Higgs Quadratic Divergence
Demir, Durmus Ali; Korutlu, Beste
2015-01-01
Here we show that, a hidden vector field whose gauge invariance is held by a Stueckelberg scalar and whose mass is spontaneously generated by the Standard Model Higgs field contributes to quadratic divergences in the Higgs boson mass squared, and even leads to its cancellation at one-loop when Higgs coupling to gauge field is fine-tuned. In contrast to mechanisms based on hidden scalars where a complete cancellation cannot be achieved, stabilization here is complete in that the hidden vector and its Stueckelberg scalar are both free from quadratic divergences at one-loop. The mechanism has observable signatures at the Large Hadron Collider.
(Eigen Phoneme Space (Phoneme Vector : PV)
Takiguchi, Tetsuya
) (Phoneme Vector : PV) Fig. 1 (EPS) /a/ /i/ · · · PCA (EPS) 2.2 PCA PCA i Si Si = 1 N N t=1 (xi t - ¯xi )(xi (6) #12;Fig. 2 Phoneme Vector (PV) extraction (6) yt (Q×M) yt PCA y t y t = V T (yt - ¯y) (7) V = [1 , 2 , · · · , R ] R Fig. 2 3 3.1 DCT PCA MFCC PCA PV 32 16 32 (Q) 5 21 2 ATR A-SET 2,620 54 HMM 1
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.
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.
Lie algebra solution of population models based on time-inhomogeneous Markov chains
House, Thomas
2011-01-01
Many natural populations are well modelled through time-inhomogeneous stochastic processes. Such processes have been analysed in the physical sciences using a method based on Lie algebras, but this methodology is not widely used for models with ecological, medical and social applications. This paper presents the Lie algebraic method, and applies it to three biologically well motivated examples. The result of this is a solution form that is often highly computationally advantageous.
DISCRETE MODELS FOR THE p-LOCAL HOMOTOPY THEORY OF COMPACT LIE GROUPS AND p-COMPACT GROUPS
Oliver, Bob
. Secondary 55R40, 57T1* *0. Key words and phrases. Classifying space, p-completion, fusion, compact Lie g DISCRETE MODELS FOR THE p-LOCAL HOMOTOPY THEORY OF COMPACT LIE GROUPS AND p-COMPACT a certain class of spaces which includes p-* *completed classifying spaces of compact Lie groups
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.
GAL4 Two-Hybrid Vectors Handbook
Erickson, F. Les
Libraries FOR RESEARCH USE ONLY (PR6X890) #12;MATCHMAKER GAL4 Two-Hybrid Vectors Handbook CLONTECH used in the yeast GAL4-based MATCHMAKER Two-Hybrid Systems and Libraries. For ease of use on synthetic defined medium lacking tryptophan or leucine, respectively. The nutritional markers also allow
A review of learning vector quantization classifiers
Nova, David
2015-01-01
In this work we present a review of the state of the art of Learning Vector Quantization (LVQ) classifiers. A taxonomy is proposed which integrates the most relevant LVQ approaches to date. The main concepts associated with modern LVQ approaches are defined. A comparison is made among eleven LVQ classifiers using one real-world and two artificial datasets.
MULTIPLE BUYING OR SELLING WITH VECTOR OFFERS
Ferguson, Thomas S.
MULTIPLE BUYING OR SELLING WITH VECTOR OFFERS F. THOMAS BRUSS , Universit´e Libre de Bruxelles of the house-selling problem to selling k houses. Let the offers, X1, X2, . . ., be independent, identically with recall of past offers and to problems with a discount. KEYWORDS: OPTIMAL STOPPING, HOUSE-SELLING, JOB
Averages in vector spaces over finite fields
Wright J.; Carbery A.; Stones B.
2008-01-01
We study the analogues of the problems of averages and maximal averages over a surface in R-n when the euclidean structure is replaced by that of a vector space over a finite field, and obtain optimal results in a number ...
Support Vector Machines with Example Dependent Costs
Brefeld, Ulf
Support Vector Machines with Example Dependent Costs Ulf Brefeld, Peter Geibel, and Fritz Wysotzki neu- ral networks and machine learning, typically, do not take any costs into account or allow only costs depending on the classes of the examples that are used for learning. As an extension of class
RESEARCH ARTICLE Axisymmetric Coanda-assisted vectoring
Smith, Barton L.
the primary jet to vector as well. D. Allen Á B. L. Smith (&) Mechanical and Aerospace Engineering, Utah State An experimental demonstration of a jet vec- toring technique used in our novel spray method called Coanda through the interaction of two jets: a primary jet and a control jet. The primary jet has larger volume
Electric Magnetic Duality in String Theory
Ashoke Sen
1992-10-06
The electric-magnetic duality transformation in four dimensional heterotic string theory discussed by Shapere, Trivedi and Wilczek is shown to be an exact symmetry of the equations of motion of low energy effective field theory even after including the scalar and the vector fields, arising due to compactification, in the effective field theory. Using this duality transformation we construct rotating black hole solutions in the effective field theory carrying both, electric and magnetic charges. The spectrum of extremal magnetically charged black holes turns out to be similar to that of electrically charged elementary string excitations. We also discuss the possibility that the duality symmetry is an exact symmetry of the full string theory under which electrically charged elementary string excitations get exchanged with magnetically charged soliton like solutions. This proposal might be made concrete following the suggestion of Dabholkar et. al. that fundamental strings may be regarded as soliton like classical solutions in the effective field theory.
Can (Electric-Magnetic) Duality Be Gauged?
Claudio Bunster; Marc Henneaux
2014-03-13
There exists a formulation of the Maxwell theory in terms of two vector potentials, one electric and one magnetic. The action is then manifestly invariant under electric-magnetic duality transformations, which are rotations in the two-dimensional internal space of the two potentials, and local. We ask the question: can duality be gauged? The only known and battled-tested method of accomplishing the gauging is the Noether procedure. In its decanted form, it amounts to turn on the coupling by deforming the abelian gauge group of the free theory, out of whose curvatures the action is built, into a non-abelian group which becomes the gauge group of the resulting theory. In this article, we show that the method cannot be successfully implemented for electric-magnetic duality. We thus conclude that, unless a radically new idea is introduced, electric-magnetic duality cannot be gauged. The implication of this result for supergravity is briefly discussed.
\\(?\\) vector and axial-vector spectral functions in the extended linear sigma model
A. Habersetzer; Francesco Giacosa
2015-04-16
The extended linear sigma model describes the vacuum phenomenology of scalar, pseudoscalar, vector and axial-vector mesons at energies \\(\\simeq 1\\text{ GeV}\\). We combine the chiral \\(U(2)_L\\times U(2)_R\\) symmetry of this model with a local \\(SU(2)_L\\times U(1)_Y\\) symmetry and obtain a gauge invariant effective description for electroweak interaction of hadrons in the vacuum. Vector and axial-vector spectral functions can be described well by two intermediate resonances \\(\\rho\\) and \\(a_1\\). They are implemented into this model as chiral partners and yield the predominant contributions to both spectral functions. However, the contributions that arise from the non-resonant decay channels of the weak charged \\(W\\) bosons are essential for reproducing the lineshapes of the spectral functions.
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.
Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar
Gandini, Paolo; /Milan U. /INFN, Milan
2012-04-06
We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different behavior: the measured value of f{sub L} {approx} 0.5 in B {yields} {phi}K* decays is in contrast with naive Standard Model (SM) calculations. Several solutions have been proposed such as the introduction of non-factorizable terms and penguin-annihilation amplitudes, while other explanations invoke new physics. New modes have been investigated to shed more light on the problem.
Bowman,John C.
Is Sometimes A One-way Road On A Tall Narrow Bridge Over A Shal- low Muddy River, On Whose South Bank Lies? Fuck you. #12;4 Normal Vector GOVER N MENT SMASHTHESTATE PO LICE BU R EAUCRA C Y TAXES LAWYERS
Carbon stable isotopes suggest that hippopotamus-vectored nutrients subsidize
Lewison, Rebecca
Carbon stable isotopes suggest that hippopotamus-vectored nutrients subsidize aquatic consumers that hippopotamus-vectored nutrients subsidize aquatic consumers in an East African river. Ecosphere 6(4):52. http
An evaluation of support vector machines in consumer credit analysis
Mattocks, Benjamin A
2013-01-01
This thesis examines a support vector machine approach for determining consumer credit. The support vector machine using a radial basis function (RBF) kernel is compared to a previous implementation of a decision tree ...
Orthogonal Sets of Vectors and the Gram-Schmidt Process
PRETEX (Halifax NS) #1 1054 1999 Mar 05 10:59:16
2010-02-12
2007/2/16 page 323 i i i i. 4.12. Orthogonal Sets of Vectors and the Gram-Schmidt Process 323. 16. Using Equation (4.11.11), determine all vectors sat- isfying ?v ...
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
Prediction of Solar Flare Size and Time-to-Flare Using Support Vector Machine Regression
Boucheron, Laura E; McAteer, R T James
2015-01-01
We study the prediction of solar flare size and time-to-flare using 38 features describing magnetic complexity of the photospheric magnetic field. This work uses support vector regression to formulate a mapping from the 38-dimensional feature space to a continuous-valued label vector representing flare size or time-to-flare. When we consider flaring regions only, we find an average error in estimating flare size of approximately half a \\emph{geostationary operational environmental satellite} (\\emph{GOES}) class. When we additionally consider non-flaring regions, we find an increased average error of approximately 3/4 a \\emph{GOES} class. We also consider thresholding the regressed flare size for the experiment containing both flaring and non-flaring regions and find a true positive rate of 0.69 and a true negative rate of 0.86 for flare prediction. The results for both of these size regression experiments are consistent across a wide range of predictive time windows, indicating that the magnetic complexity fe...
Light Vector Mesons in the Nuclear Medium
Wood, Michael; Nasseripour, Rakhsha; Weygand, Dennis; Djalali, Chaden; Tur, Clarisse; Mosel, Ulrich; Muehlich, Pascal; Adams, Gary; Amaryan, Moscov; Amaryan, Moskov; Ambrozewicz, Pawel; Anghinolfi, Marco; Asryan, Gegham; Avagyan, Harutyun; Baghdasaryan, Hovhannes; Baillie, Nathan; Ball, James; Baltzell, Nathan; Barrow, Steve; Battaglieri, Marco; Bedlinskiy, Ivan; Bektasoglu, Mehmet; Bellis, Matthew; Benmouna, Nawal; Berman, Barry; Biselli, Angela; Blaszczyk, Lukasz; Bouchigny, Sylvain; Boyarinov, Sergey; Bradford, Robert; Branford, Derek; Briscoe, William; Brooks, William; Burkert, Volker; Butuceanu, Cornel; Calarco, John; Careccia, Sharon; Carman, Daniel; Carnahan, Bryan; Casey, Liam; Chen, Shifeng; Cheng, Lu; Cole, Philip; Collins, Patrick; Coltharp, Philip; Crabb, Donald; Crannell, Hall; Crede, Volker; Cummings, John; Dashyan, Natalya; De Vita, Raffaella; De Sanctis, Enzo; Degtiarenko, Pavel; Denizli, Haluk; Dennis, Lawrence; Deur, Alexandre; Dharmawardane, Kahanawita; Dickson, Richard; Dodge, Gail; Doughty, David; Dugger, Michael; Dytman, Steven; Dzyubak, Oleksandr; Egiyan, Hovanes; Egiyan, Kim; Elfassi, Lamiaa; Elouadrhiri, Latifa; Eugenio, Paul; Fedotov, Gleb; Feldman, Gerald; Feuerbach, Robert; Fradi, Ahmed; Funsten, Herbert; Garcon, Michel; Gavalian, Gagik; Gilfoyle, Gerard; Giovanetti, Kevin; Girod, Francois-Xavier; Goetz, John; Gordon, Christopher; Gothe, Ralf; Griffioen, Keith; Guidal, Michel; Guler, Nevzat; Guo, Lei; Gyurjyan, Vardan; Hadjidakis, Cynthia; Hafidi, Kawtar; Hakobyan, Hayk; Hakobyan, Rafael; Hanretty, Charles; Hardie, John; Hassall, Neil; Hersman, F.; Hicks, Kenneth; Hleiqawi, Ishaq; Holtrop, Maurik; Hyde, Charles; Ilieva, Yordanka; Ireland, David; Ishkhanov, Boris; Isupov, Evgeny; Ito, Mark; Jenkins, David; Jo, Hyon-Suk; Johnstone, John; Joo, Kyungseon; Juengst, Henry; Kalantarians, Narbe; Kellie, James; Khandaker, Mahbubul; Khetarpal, Puneet; Kim, Wooyoung; Klein, Andreas; Klein, Franz; Klimenko, Alexei; Kossov, Mikhail; Krahn, Zebulun; Kramer, Laird; Kubarovsky, Valery; Kuhn, Joachim; Kuhn, Sebastian; Kuleshov, Sergey; Lachniet, Jeff; Laget, Jean; Langheinrich, Jorn; Lawrence, David; Li, Ji; Livingston, Kenneth; Lu, Haiyun; MacCormick, Marion; Markov, Nikolai; Mattione, Paul; McAleer, Simeon; McKinnon, Bryan; McNabb, John; Mecking, Bernhard; Mehrabyan, Surik; Melone, Joseph; Mestayer, Mac; Meyer, Curtis; Mibe, Tsutomu; Mikhaylov, Konstantin; Minehart, Ralph; Mirazita, Marco; Miskimen, Rory; Mokeev, Viktor; Moriya, Kei; Morrow, Steven; Moteabbed, Maryam; Mueller, James; Munevar Espitia, Edwin; Mutchler, Gordon; Nadel-Turonski, Pawel; Niccolai, Silvia; Niculescu, Gabriel; Niculescu, Maria-Ioana; Niczyporuk, Bogdan; Niroula, Megh; Niyazov, Rustam; Nozar, Mina; Osipenko, Mikhail; Ostrovidov, Alexander; Park, Kijun; Pasyuk, Evgueni; Paterson, Craig; Pereira, Sergio; Pierce, Joshua; Pivnyuk, Nikolay; Pocanic, Dinko; Pogorelko, Oleg; Pozdnyakov, Sergey; Preedom, Barry; Price, John; Prok, Yelena; Protopopescu, Dan; Raue, Brian; Riccardi, Gregory; Ricco, Giovanni; Ripani, Marco; Ritchie, Barry; Ronchetti, Federico; Rosner, Guenther; Rossi, Patrizia; Sabatie, Franck; Salamanca, Julian; Salgado, Carlos; Santoro, Joseph; Sapunenko, Vladimir; Schumacher, Reinhard; Serov, Vladimir; Sharabian, Youri; Sharov, Dmitri; Shvedunov, Nikolay; Smith, Elton; Smith, Lee; Sober, Daniel; Sokhan, Daria; Stavinsky, Aleksey; Stepanyan, Stepan; Stepanyan, Samuel; Stokes, Burnham; Stoler, Paul; Strakovski, Igor; Strauch, Steffen; Taiuti, Mauro; Tedeschi, David; Tkabladze, Avtandil; Tkachenko, Svyatoslav; Todor, Luminita; Ungaro, Maurizio; Vineyard, Michael; Vlassov, Alexander; Watts, Daniel; Weinstein, Lawrence; Williams, Michael; Wolin, Elliott; Yegneswaran, Amrit; Zana, Lorenzo; Zhang, Bin; Zhang, Jixie; Zhao, Bo; Zhao, Zhiwen
2008-07-01
The light vector mesons ($\\rho$, $\\omega$, and $\\phi$) were produced in deuterium, carbon, titanium, and iron targets in a search for possible in-medium modifications to the properties of the $\\rho$ meson at normal nuclear densities and zero temperature. The vector mesons were detected with the CEBAF Large Acceptance Spectrometer (CLAS) via their decays to $e^{+}e^{-}$. The rare leptonic decay was chosen to reduce final-state interactions. A combinatorial background was subtracted from the invariant mass spectra using a well-established event-mixing technique. The $\\rho$ meson mass spectrum was extracted after the $\\omega$ and $\\phi$ signals were removed in a nearly model-independent way. Comparisons were made between the $\\rho$ mass spectra from the heavy targets ($A > 2$) with the mass spectrum extracted from the deuterium target. With respect to the $\\rho$-meson mass, we obtain a small shift compatible with zero. Also, we measure widths consistent with standard nuclear many-body eff
Hessian structures, Euler vector fields, and thermodynamics
M. Á. García-Ariza
2015-11-19
This paper studies the underlying geometric structure of thermodynamics from a coordinate-free standpoint in the context of Hessian structures. The contribution of this work is the translation of the concept of "extensivity" to geometric terms by means of a vector field and an affine connection. It is shown that entropy's being extensive is equivalent to the vector's being a null direction of the Hessian structure. The latter induces a metric tensor-a generalized version of Ruppeiner's metrics-on the Riemannian Hessian submanifolds of a system's space of equilibrium states. These are embedded, and locally described as level sets of extensive functions. Under this approach, total Legendre transforms and intensive functions are given a straightforward geometrical meaning. The invariance of the metrics under total Legendre transforms is readily observed.
Higgs Portal Vector Dark Matter : Revisited
Seungwon Baek; P. Ko; Wan-Il Park; Eibun Senaha
2013-04-15
We revisit the Higgs portal vector dark matter model including a hidden sector Higgs field that generates the mass of the vector dark matter. The model becomes renormalizable and has two scalar bosons, the mixtures of the standard model (SM) Higgs and the hidden sector Higgs bosons. The strong bound from direct detection such as XENON100 is evaded due to the cancellation mechanism between the contributions from two scalar bosons. As a result, the model becomes still viable in large range of dark matter mass, contrary to some claims in the literature. The Higgs properties are also affected, the signal strengths for the Higgs boson search being universally suppressed relative to the SM value, which could be tested at the LHC in the future.
Higgsed Stueckelberg Vector and Higgs Quadratic Divergence
Durmus Ali Demir; Canan Nurhan Karahan; Beste Korutlu
2014-09-28
Here we show that, a hidden vector field whose gauge invariance is ensured by a Stueckelberg scalar and whose mass is spontaneously generated by the Standard Model Higgs field contributes to quadratic divergences in the Higgs boson mass squared, and even leads to its cancellation at one-loop when Higgs coupling to gauge field is fine-tuned. In contrast to mechanisms based on hidden scalars where a complete cancellation cannot be achieved, stabilization here is complete in that the hidden vector and the accompanying Stueckelberg scalar are both free from quadratic divergences at one-loop. This stability, deriving from hidden exact gauge invariance, can have important implications for modelling dark phenomena like dark matter, dark energy, dark photon and neutrino masses. The hidden fields can be produced at the LHC.
Probabilistic Wind Vector Forecasting Using Ensembles and Bayesian Model Averaging
Raftery, Adrian
Probabilistic Wind Vector Forecasting Using Ensembles and Bayesian Model Averaging J. MCLEAN 2011, in final form 26 May 2012) ABSTRACT Probabilistic forecasts of wind vectors are becoming critical with univariate quantities, statistical approaches to wind vector forecasting must be based on bivariate
Natural units and the vector space of physical values
Ansmann, Gerrit
2015-01-01
We explore the mathematical foundations of the vector space of physical dimensions introduced in A. Maksymowicz, Am. J. Phys. 44, 1976, and extend this formalism to the vector space of physical values. As different unit systems correspond to different bases of this vector space, our formalism may find use for introducing the concept of natural units and transforming physical values between unit systems.
Agilent E8267D PSG Vector Signal Generator
Anlage, Steven
Agilent E8267D PSG Vector Signal Generator Configuration Guide This guide is intended to assist you with the ordering process of the PSG vector signal generators. #12;2 Agilent PSG Vector Signal Generator Options generator. E8267D-532 Frequency range from 250 kHz to 31.8 GHz Selects the maximum frequency of the signal
SELECTION OF VARIABLES FOR REGULATORY CONTROL USING POLE VECTORS
Skogestad, Sigurd
SELECTION OF VARIABLES FOR REGULATORY CONTROL USING POLE VECTORS Kjetil Havre 1 Sigurd Skogestad 2: This paper consider control structure design using the information given in the pole vectors. It is shown how the input and output pole vectors are related to the minimum input energy needed to stabilize a given
SELECTION OF VARIABLES FOR REGULATORY CONTROL USING POLE VECTORS
Skogestad, Sigurd
SELECTION OF VARIABLES FOR REGULATORY CONTROL USING POLE VECTORS Kjetil Havre1 Sigurd Skogestad 2: This paper consider control structure design using the information given in the pole vectors. It is shown how the input and output pole vectors are related to the minimum input energy needed to stabilize a given
Low-lying 2$^+$ states generated by $pn$-quadrupole correlation and $N=28$ shell quenching
Shuichiro Ebata; Masaaki Kimura
2014-11-12
The quadrupole vibrational modes of neutron-rich $N$=28 isotones ($^{48}$Ca, $^{46}$Ar, $^{44}$S and $^{42}$Si) are investigated using the canonical-basis time-dependent Hartree-Fock-Bogoliubov theory with several choice of energy density functionals, including nuclear pairing correlation. It is found that the quenching of $N$=28 shell gap and the proton holes in the $sd$-shell trigger quadrupole correlation and increase the collectivity of the low-lying 2$^+$ state in $^{46}$Ar. It is also found that the pairing correlation plays an important role to increase the collectivity. We also demonstrate that the same mechanism to enhance the low-lying collectivity applies to other $N$=28 isotones $^{44}$S and $^{42}$Si, and it generates a couple of low-lying 2$^+$ states which can be associated with the observed $2^+$ states.
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.
Statistical study of free magnetic energy and flare productivity of solar active regions
Su, J. T.; Jing, J.; Wang, S.; Wang, H. M. [Space Weather Research Laboratory, New Jersey Institute of Technology, University Heights, Newark, NJ 07102-1982 (United States); Wiegelmann, T., E-mail: sjt@bao.ac.cn [Max-Planck-Institut fur Sonnensystemforschung, Max-Planck-Strasse 2, D-37191 Katlenburg-Lindau (Germany)
2014-06-20
Photospheric vector magnetograms from the Helioseismic and Magnetic Imager on board the Solar Dynamic Observatory are utilized as the boundary conditions to extrapolate both nonlinear force-free and potential magnetic fields in solar corona. Based on the extrapolations, we are able to determine the free magnetic energy (FME) stored in active regions (ARs). Over 3000 vector magnetograms in 61 ARs were analyzed. We compare FME with the ARs' flare index (FI) and find that there is a weak correlation (<60%) between FME and FI. FME shows slightly improved flare predictability relative to the total unsigned magnetic flux of ARs in the following two aspects: (1) the flare productivity predicted by FME is higher than that predicted by magnetic flux and (2) the correlation between FI and FME is higher than that between FI and magnetic flux. However, this improvement is not significant enough to make a substantial difference in time-accumulated FI, rather than individual flare, predictions.
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 &
Vector potential and Berry-phase-induced force in dissipative systems
Yi, X. X. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China); College of Advanced Science and Technology, Dalian University of Technology, Dalian 116024 (China); Wang, W. [School of Physics and Optoelectronic Technology, Dalian University of Technology, Dalian 116024 (China)
2007-10-15
The vector potential and Berry-phase-induced force in a dissipative hybrid system are studied in this paper. The hybrid system is a compound of a classical magnetic particle and a quantum single spin. Two cases are considered. In the first case, we investigate the effect of the dissipative quantum subsystem on the motion of its classical partner, whereas in the second case, we show how the dynamics of the quantum single spin are affected by the dissipation of the classical particle. Extension to general dissipative hybrid systems is discussed.
A General Method for Deriving Vector Potentials Produced by Knotted Solenoids
V. V. Sreedhar
2015-01-06
A general method for deriving exact expressions for vector potentials produced by arbitrarily knotted solenoids is presented. It consists of using simple physics ideas from magnetostatics to evaluate the magnetic field in a surrogate problem. The latter is obtained by modelling the knot with wire segments carrying steady currents on a cubical lattice. The expressions for a 31 (trefoil) and a 41 (figure-eight) knot are explicitly worked out. The results are of some importance in the study of the Aharonov-Bohm effect generalised to a situation in which charged particles moving through force-free regions are scattered by fluxes confined to the interior of knotted impenetrable tubes.
Bouchard, Louis-Serge; Pines, Alexander; Demas, Vasiliki
2014-01-21
A system and method for Fourier encoding a nuclear magnetic resonance (NMR) signal is disclosed. A static magnetic field B.sub.0 is provided along a first direction. An NMR signal from the sample is Fourier encoded by applying a rotating-frame gradient field B.sub.G superimposed on the B.sub.0, where the B.sub.G comprises a vector component rotating in a plane perpendicular to the first direction at an angular frequency .omega.in a laboratory frame. The Fourier-encoded NMR signal is detected.
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.
Low-lying Eigenvalues of the improved Wilson-Dirac Operator in QCD
Hubert Simma; Douglas Smith
1998-01-20
The spectral flow of the low-lying eigenvalues of the improved and unimproved Wilson-Dirac operator is studied on instanton-like configurations and on thermalized quenched configurations at various $\\beta$-values and lattice sizes. We also investigate the space-time localisation and chirality of the corresponding eigenvectors.
Friday, January 24 -1:00pm Goldfield Room, Lied Library
Hemmers, Oliver
of their industry's past and share current trends. Thursday, February 27 - 5:00pm Houssels House (HOU) Library WatchFriday, January 24 - 1:00pm Goldfield Room, Lied Library Be part of this historic moment and view the "Documenting the African American Experience in LasVegas" website (http://digital.library
In Vivo Optical Microendoscopy for Imaging Cells Lying Deep within Live Tissue
Schnitzer, Mark
1 50 In Vivo Optical Microendoscopy for Imaging Cells Lying Deep within Live Tissue ABSTRACT hippocampal area, but our general approach is broadly applicable to other deep brain regions and areas by standard water-immersion microscope objectives. Microendoscopes are also compatible with chronic animal
The Generic Graph Component Library LieQuan Lee Jeremy G. Siek Andrew Lumsdaine
Lumsdaine, Andrew
The Generic Graph Component Library LieQuan Lee Jeremy G. Siek Andrew Lumsdaine Laboratory In this paper we present the Generic Graph Component Library (GGCL), a generic programming framework for graph data struc tures and graph algorithms. Following the theme of the Standard Template Library (STL
Low-lying states in $^{30}$Mg: a beyond relativistic mean-field investigation
J. M. Yao; Z. X. Li; J. Xiang; H. Mei; J. Meng
2010-10-21
The recently developed model of three-dimensional angular momentum projection plus generator coordinate method on top of triaxial relativistic mean-field states has been applied to study the low-lying states of $^{30}$Mg. The effects of triaxiality on the low-energy spectra and E0 and E2 transitions are examined.
Projection of the low-lying eigenmodes of the overlap Dirac operator in lattice QCD
Ting-Wai Chiu; Tung-Han Hsieh
2014-12-08
We outline our implementation of the adaptive thick-restart Lanczos algorithm ($a$-TRLan) for the projection of the low-lying eigenmodes of the overlap Dirac operator in lattice QCD, and compare the performances of our code and the widely used package ARPACK.
The Z*-theorem for compact Lie groups Guido Mislin Jacques Thevenaz
ThÃ©venaz, Jacques
The Z*-theorem for compact Lie groups Guido Mislin Jacques ThÂ´evenaz Mathematik Institut de Math the assumption on x in terms of control of fusion. For an arbitrary group G and a prime p, we say that a subgroup H of G controls finite p-fusion in G if the following two conditions are satisfied: (a) every finite
Lie Group Integrators for Animation and Control of Vehicles Marin Kobilarov Keenan Crane
Grinspun, Eitan
dynamics such as helicopters, boats, and cars. Moti- vated by recent developments in discrete geometric environment, such as a car, helicopter, or boat. While vehicles constitute a highly visible component for all sorts of vehicles, including cars, boats, and helicopters. These Lie group-based integrators
Lee, Ruby B.
Specifying and Verifying Hardware for Tamper-Resistant Software David Lie John Mitchell Abstract We specify a hardware architecture that supports tamper-resistant software by identifying) to compare executions of the idealized and actual models. In this approach, software tampering occurs
How to Lie with Big Data (and/or big computations)
Stark, Philip B.
How to Lie with Big Data (and/or big computations) Philip B. Stark Department of Statistics experimental design doesn't matter #12;What's new in Big Data? · design still matters; experiments versus flu trends http://bits.blogs.nytimes.com/2014/03/28/ google-flu-trends-the-limits-of-big-data/ #12
Using VMM-Based Sensors to Monitor Honeypots Kurniadi Asrigo Lionel Litty David Lie
Lie, David
of Electrical and Computer Engineering University of Toronto {kuas,llitty,lie}@eecg.toronto.edu Abstract Virtual on honeypots. We document and evaluate three designs we have implemented on two open- source virtualization to lists, requires prior specific permission and/or a fee. VEE'06 June 1416, 2006, Ottawa, Ontario, Canada
Vector Norms and Matrix Norms 6.1 Normed Vector Spaces
Gallier, Jean
R, if , 0, then p p + q q . () (2) For any two vectors u, v 2 E, we have nX i=1 |uivi| kukp kvkq . () #12;6.1. NORMED VECTOR SPACES 377 For p > 1 and 1/p + 1/q = 1, the inequality nX i=1 |uivi| nX i=1 |ui|p 1/p nX i=1 |vi|q 1/q is known as HÂ¨older's inequality. For p = 2, it is the Cauchy
A cosmic vector for dark energy
Jose Beltran Jimenez; Antonio L. Maroto
2008-08-15
In this work we show that the presence of a vector field on cosmological scales could explain the present phase of accelerated expansion of the universe. The proposed theory contains no dimensional parameters nor potential terms and does not require unnatural initial conditions in the early universe, thus avoiding the so called cosmic coincidence problem. In addition, it fits the data from high-redshift supernovae with excellent precision, making definite predictions for cosmological parameters. Upcoming observations will be able to clearly discriminate this model from standard cosmology with cosmological constant.
Supersymmetry and Vector-like Extra Generation
Chun Liu
2009-07-17
Within the framework of supersymmetry, the particle content is extended in a way that each Higgs doublet is in a full generation. Namely in addition to ordinary three generations, there is an extra vector-like generation, and it is the extra slepton SU(2)_L doublets that are taken to be the two Higgs doublets. R-parity violating interactions contain ordinary Yukawa interactions. Breaking of supersymmetry and gauge symmetry are analyzed. Fermion and boson spectra are calculated. Phenomenological constraints and relevant new physics at Large Hadron Collider are discussed.
N. V. Antonov; N. M. Gulitskiy
2015-01-21
Inertial-range asymptotic behavior of a vector (e.g., magnetic) field, passively advected by a strongly anisotropic turbulent flow, is studied by means of the field theoretic renormalization group and the operator product expansion. The advecting velocity field is Gaussian, not correlated in time, with the pair correlation function of the form $\\propto \\delta(t-t') / k_{\\bot}^{d-1+\\xi}$, where $k_{\\bot}=|{\\bf k}_{\\bot}|$ and ${\\bf k}_{\\bot}$ is the component of the wave vector, perpendicular to the distinguished direction (`direction of the flow') -- the $d$-dimensional generalization of the ensemble introduced by Avellaneda and Majda [{\\it Commun. Math. Phys.} {\\bf 131}: 381 (1990)]. The stochastic advection-diffusion equation for the transverse (divergence-free) vector field includes, as special cases, the kinematic dynamo model for magnetohydrodynamic turbulence and the linearized Navier--Stokes equation. In contrast to the well known isotropic Kraichnan's model, where various correlation functions exhibit anomalous scaling behavior with infinite sets of anomalous exponents, here the dependence on the integral turbulence scale $L$ has a logarithmic behavior: instead of power-like corrections to ordinary scaling, determined by naive (canonical) dimensions, the anomalies manifest themselves as polynomials of logarithms of $L$. The key point is that the matrices of scaling dimensions of the relevant families of composite operators appear nilpotent and cannot be diagonalized. The detailed proof of this fact is given for correlation functions of arbitrary order.
Vectorizing the Community Land Model (CLM)
Hoffman, Forrest M [ORNL; Vertenstein, Mariana [National Center for Atmospheric Research (NCAR); Kitabata, Hideyuki [Central Research Institute of Electric Power Industry, Japan; White III, James B [ORNL
2005-01-01
In this paper we describe our extensive efforts to rewrite the Community Land Model (CLM) so that it provides good vector performance on the Earth Simulator in Japan and the Cray X1 at Oak Ridge National Laboratory. We present the technical details of the old and new internal data structures, the required code reorganization, and the resulting performance improvements. We describe and compare the performance and scaling of the final CLM Version 3.0 (CLM3.0) on the IBM Power4, the Earth Simulator, and the Cray X1. At 64 processors, the performance of the model is similar on the IBM Power4, the Earth Simulator, and the Cray X1. However, the Cray X1 offers the best performance of all three platforms tested from 4 to 64 processors when OpenMP is used. Moreover, at low processor counts (16 or fewer), the model performs significantly better on the Cray X1 than on the other platforms. The vectorized version of CLM was publicly released by the National Center for Atmospheric Research as the standalone CLM3.0, as a part of the new Community Atmosphere Model Version 3.0 (CAM3.0), and as a component of the Community Climate System Model Version 3.0 (CCSM3.0) on June 23, 2004.
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.
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.
He Lung Imaging in an Open Access, Very-Low-Field Human Magnetic Resonance Imaging System
Walsworth, Ronald L.
3 He Lung Imaging in an Open Access, Very-Low-Field Human Magnetic Resonance Imaging System R. W. Butler,6 F. W. Hersman,4 and R. L. Walsworth1 The human lung and its functions are extremely sensitive lung restrict sub- jects to lying horizontally. Imaging of human lungs using inhaled laser-polarized 3
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
Stanislav S. Zub; Sergiy I. Zub
2015-08-17
It was proposed the Lie group such that symplectic structure of orbits of co-adjoint representation of the group is revealed symplectic structure of a rigid body dynamics in quaternion variables. It is shown that Poisson brackets of corresponding Lie-Poisson structure coincide with canonical Poisson brackets on cotangent bundle of group unit quaternions.
Does the Poynting vector always represent electromagnetic power flow?
Changbiao Wang
2015-07-07
Poynting vector as electromagnetic power flow has prevailed over one hundred years in the community. However in this paper, it is shown from Maxwell equations that the Poynting vector may not represent the electromagnetic power flow for a plane wave in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; this important conclusion revises the conventional understanding of Poynting vector. It is also shown that this conclusion is clearly supported by Fermat's principle and special theory of relativity.
Vector Higgs bosons and possible suppression of flavorchanging neutral current
Xiao Yu Qian
2006-10-17
We replace the scalar Higgs doublet with a vector Higgs boson doublet to the unified electroweak W-S model and find most of important features of W-S model are kept unchanged only the Higgs boson now become vector bosons. Lorentz invariance has been carefully discussed. The most important challenge is there will be three massless vector Higgs bosons. The remarkable effect is the possible suppression of the flavorchanging neutral current compare to the multi-Higgs model.
Does the Poynting vector always represent electromagnetic power flow?
Wang, Changbiao
2015-01-01
Poynting vector as electromagnetic power flow has prevailed over one hundred years in the community. However in this paper, it is shown from Maxwell equations that the Poynting vector may not represent the electromagnetic power flow for a plane wave in a non-dispersive, lossless, non-conducting, anisotropic uniform medium; this important conclusion revises the conventional understanding of Poynting vector. It is also shown that this conclusion is clearly supported by Fermat's principle and special theory of relativity.
Magnetic field restructuring associated with two successive solar eruptions
Wang, Rui; Liu, Ying D.; Yang, Zhongwei; Hu, Huidong
2014-08-20
We examine two successive flare eruptions (X5.4 and X1.3) on 2012 March 7 in the NOAA active region 11429 and investigate the magnetic field reconfiguration associated with the two eruptions. Using an advanced non-linear force-free field extrapolation method based on the SDO/HMI vector magnetograms, we obtain a stepwise decrease in the magnetic free energy during the eruptions, which is roughly 20%-30% of the energy of the pre-flare phase. We also calculate the magnetic helicity and suggest that the changes of the sign of the helicity injection rate might be associated with the eruptions. Through the investigation of the magnetic field evolution, we find that the appearance of the 'implosion' phenomenon has a strong relationship with the occurrence of the first X-class flare. Meanwhile, the magnetic field changes of the successive eruptions with implosion and without implosion were well observed.
A Numerical Comparison of Rule Ensemble Methods and Support Vector...
Office of Scientific and Technical Information (OSTI)
Title: A Numerical Comparison of Rule Ensemble Methods and Support Vector Machines Machine or statistical learning is a growing field that encompasses many scientific problems...
Using support vector machines to improve elemental ion identification...
Office of Scientific and Technical Information (OSTI)
elemental ions in X-ray crystal structures has been extended to use support vector machine (SVM) classifiers trained on selected structures in the PDB, with significantly...
J.S. 24 POWER TRANSMISSION AND DISTRIBUTION; VECTORS; ELECTRIC...
Office of Scientific and Technical Information (OSTI)
power and power factor of instantaneous phasors Hsu, J.S. 24 POWER TRANSMISSION AND DISTRIBUTION; VECTORS; ELECTRIC CURRENTS; ELECTRIC POTENTIAL; MONITORING; POWER SYSTEMS;...
Statistical anisotropy of the curvature perturbation from vector field perturbations
Dimopoulos, Konstantinos; Karciauskas, Mindaugas; Lyth, David H.; Rodriguez, Yeinzon E-mail: m.karciauskas@lancaster.ac.uk E-mail: yeinzon.rodriguez@uan.edu.co
2009-05-15
The {delta}N formula for the primordial curvature perturbation {zeta} is extended to include vector as well as scalar fields. Formulas for the tree-level contributions to the spectrum and bispectrum of {zeta} are given, exhibiting statistical anisotropy. The one-loop contribution to the spectrum of {zeta} is also worked out. We then consider the generation of vector field perturbations from the vacuum, including the longitudinal component that will be present if there is no gauge invariance. Finally, the {delta}N formula is applied to the vector curvaton and vector inflation models with the tensor perturbation also evaluated in the latter case.
Cosmological evolution in vector-tensor theories of gravity
Jose Beltran Jimenez; Antonio L. Maroto
2009-09-06
We present a detailed study of the cosmological evolution in general vector-tensor theories of gravity without potential terms. We consider the evolution of the vector field throughout the expansion history of the universe and carry out a classification of models according to the behavior of the vector field in each cosmological epoch. We also analyze the case in which the universe is dominated by the vector field, performing a complete analysis of the system phase map and identifying those attracting solutions which give rise to accelerated expansion. Moreover, we consider the evolution in a universe filled with a pressureless fluid in addition to the vector field and study the existence of attractors in which we can have a transition from matter-domination to vector-domination with accelerated expansion so that the vector field may play the role of dark energy. We find that the existence of solutions with late-time accelerated expansion is a generic prediction of vector-tensor theories and that such solutions typically lead to the presence of future singularities. Finally, limits from local gravity tests are used to get constraints on the value of the vector field at small (Solar System) scales.
Syllabus for MATH 362 Spring 2015: Topics in Vector Calculus
2014-12-23
Dec 23, 2014 ... ... basics of vector calculus, from the definition of cartesian coordinates to Stokes ... The breakdown of the credit is displayed in the table below.
Hybrid MPI/OpenMP parallel support vector machine training
Kristian Woodsend
2009-01-12
Jan 12, 2009 ... A parallel implementation of Support Vector Machine training has been developed, using a combination of MPI and OpenMP. Using an interior ...
Multi-group Support Vector Machines with measurement costs
Emilio Carrizosa
2006-05-11
May 11, 2006 ... Multi-group Support Vector Machines with measurement costs: a biobjective approach. Emilio Carrizosa (ecarrizosa ***at*** us.es)
Diffractive Production of Jets and Vector Bosons at the Tevatron
Kenichi Hatakeyama; for the CDF Collaboration
2008-12-08
Recent results on diffractive dijet and vector boson production and exclusive dijet production from the Collider Detector at Fermilab (CDF) experiment are presented.
Development Of Active Seismic Vector-Wavefield Imaging Technology...
Development Of Active Seismic Vector-Wavefield Imaging Technology For Geothermal Applications Jump to: navigation, search OpenEI Reference LibraryAdd to library Report: Development...
Singular vectors by Fusions in affine su(2)
M. Bauer; N. Sochen
1991-09-11
Explicit expressions for the singular vectors in the highest weight representations of $A_1^{(1)}$ are obtained using the fusion formalism of conformal field theory.
Low-lying Dirac eigenmodes and monopoles in 4D compact QED
Toru T. Takahashi
2007-11-09
We study the properties of low-lying Dirac modes in quenched compact QED at $\\beta$=0.99, 1.01 and 1.03, employing $12^3\\times 12$ lattices and the overlap formalism for the fermion action. We pay special attention to the spatial distributions of the low-lying Dirac modes. Near-zero modes are found to have universal anti-correlations with monopole currents below/above the critical $\\beta$. We also study the nearest-neighbor level spacing distribution of Dirac eigenvalues and find a signal of a Wigner-Poisson transition. We make a possible speculation on the chiral phase transition in 4D compact QED.
Low-lying Dirac eigenmodes and monopoles in 3+1D compact QED
Toru T. Takahashi
2008-05-30
We study the properties of low-lying Dirac modes in quenched compact QED at $\\beta =1.01$, employing $12^3\\times N_t$ ($N_t =4,6,8,10,12$) lattices and the overlap formalism for the fermion action. We pay attention to the spatial distributions of low-lying Dirac modes below and above the ``phase transition temperature'' $T_c$. Near-zero modes are found to have universal anti-correlations with monopole currents, and are found to lose their temporal structures above $T_c$ exhibiting stronger spatial localization properties. We also study the nearest-neighbor level spacing distribution of Dirac eigenvalues and find a Wigner-Poisson transition.
Lie Symmetries and Exact Solutions of the Generalized Thin Film Equation
Roman Cherniha; Phil Broadbridge; Liliia Myroniuk
2010-03-12
A symmetry group classification for fourth-order reaction-diffusion equations, allowing for both second-order and fourth-order diffusion terms, is carried out. The fourth order equations are treated, firstly, as systems of second-order equations that bear some resemblance to systems of coupled reaction-diffusion equations with cross diffusion, secondly, as systems of a second-order equation and two first-order equations. The paper generalizes the results of Lie symmetry analysis derived earlier for particular cases of these equations. Various exact solutions are constructed using Lie symmetry reductions of the reaction-diffusion systems to ordinary differential equations. The solutions include some unusual structures as well as the familiar types that regularly occur in symmetry reductions, namely self-similar solutions, decelerating and decaying traveling waves, and steady states.
Local momentum space and the vector field
David J. Toms
2014-08-04
The local momentum space expansion for the real vector field is considered. Using Riemann normal coordinates we obtain an expansion of the Feynman Green function up and including terms that are quadratic in the curvature. The results are valid for a non-minimal operator such as that arising from a general Feynman type gauge fixing condition. The result is used to derive the first three terms in the asymptotic expansion for the coincidence limit of the heat kernel without taking the trace, thus obtaining the untraced heat kernel coefficients. The spacetime dimension is kept general before specializing to four dimensions for comparison with previously known results. As a further application we re-examine the anomalous trace of the stress-energy-momentum tensor for the Maxwell field and comment on the gauge dependence.
The su(n) Lie algebraic structures in the Pegg-Barnett quantization formulation
Jian-Qi Shen
2003-11-08
We investigate the oscillator algebra of the Pegg-Barnett oscillator with a finite-dimensional number-state space and show that it possesses the su($n$) Lie algebraic structure. In addition, a so-called supersymmetric Pegg-Barnett oscillator is suggested, and the related topics such as the algebraic structure and particle occupation number of the Pegg-Barnett oscillator are briefly discussed.
Chaotic wave functions and exponential convergence of low-lying energy eigenvalues
Mihai Horoi; Alexander Volya; Vladimir Zelevinsky
1998-06-04
We suggest that low-lying eigenvalues of realistic quantum many-body hamiltonians, given, as in the nuclear shell model, by large matrices, can be calculated, instead of the full diagonalization, by the diagonalization of small truncated matrices with the exponential extrapolation of the results. We show numerical data confirming this conjecture. We argue that the exponential convergence in an appropriate basis may be a generic feature of complicated ("chaotic") systems where the wave functions are localized in this basis.
The impact of a filament eruption on nearby high-lying cool loops
Harra, L. K.; Matthews, S. A.; Long, D. M.; Doschek, G. A.; De Pontieu, B.
2014-09-10
The first spectroscopic observations of cool Mg II loops above the solar limb observed by NASA's Interface Region Imaging Spectrograph (IRIS) are presented. During the observation period, IRIS is pointed off-limb, allowing the observation of high-lying loops, which reach over 70 Mm in height. Low-lying cool loops were observed by the IRIS slit-jaw camera for the entire four-hour observing window. There is no evidence of a central reversal in the line profiles, and the Mg II h/k ratio is approximately two. The Mg II spectral lines show evidence of complex dynamics in the loops with Doppler velocities reaching ±40 km s{sup –1}. The complex motions seen indicate the presence of multiple threads in the loops and separate blobs. Toward the end of the observing period, a filament eruption occurs that forms the core of a coronal mass ejection. As the filament erupts, it impacts these high-lying loops, temporarily impeding these complex flows, most likely due to compression. This causes the plasma motions in the loops to become blueshifted and then redshifted. The plasma motions are seen before the loops themselves start to oscillate as they reach equilibrium following the impact. The ratio of the Mg h/k lines also increases following the impact of the filament.
Fusion rules and complete reducibility of certain modules for affine Lie algebras
Drazen Adamovic; Ozren Perse
2013-03-26
We develop a new method for obtaining branching rules for affine Kac-Moody Lie algebras at negative integer levels. This method uses fusion rules for vertex operator algebras of affine type. We prove that an infinite family of ordinary modules for affine vertex algebra of type A investigated in Adamovi\\'c and O. Per\\v{s}e (2008) is closed under fusion. Then we apply these fusion rules on explicit bosonic realization of level -1 modules for the affine Lie algebra of type $A_{\\ell-1}^{(1)}$, obtain a new proof of complete reducibility for these representations, and the corresponding decomposition for $\\ell \\ge 3$. We also obtain the complete reducibility of the associated level -1 modules for affine Lie algebra of type $C_{\\ell}^{(1)}$. Next we notice that the category of $D_{2 \\ell -1}^{(1)}$ modules at level $- 2 \\ell +3 $ obtained in Per\\v{s}e (2012) has the isomorphic fusion algebra. This enables us to decompose certain $E_6 ^{(1)}$ and $F_4 ^{(1)}$--modules at negative levels.
CMB anisotropies from primordial inhomogeneous magnetic fields
Antony Lewis
2004-08-19
Primordial inhomogeneous magnetic fields of the right strength can leave a signature on the CMB temperature anisotropy and polarization. Potentially observable contributions to polarization B-modes are generated by vorticity and gravitational waves sourced by the magnetic anisotropic stress. We compute the corresponding CMB transfer functions in detail including the effect of neutrinos. The shear rapidly causes the neutrino anisotropic stress to cancel the stress from the magnetic field, suppressing the production of gravitational waves and vorticity on super-horizon scales after neutrino decoupling. A significant large scale signal from tensor modes can only be produced before neutrino decoupling, and the actual amplitude is somewhat uncertain. Plausible values suggest primordial nearly scale invariant fields of ~ 10^(-10)G today may be observable from their large scale tensor anisotropy. They can be distinguished from primordial gravitational waves by their non-Gaussianity. Vector mode vorticity sources B-mode power on much smaller scales with a power spectrum somewhat similar to that expected from weak lensing, suggesting amplitudes ~ 10^(-9)G may be observable on small scales for a spectral index of n ~ -2.9. In the appendix we review the covariant equations for computing the vector and tensor CMB power spectra that we implement numerically.
Sweeney, George Franklin; Sweeney, George Franklin
2012-01-01
75 CSP #1: A vector in R 2 is defined as a space. . 78 CSP #2: stretched. . 89 CSP # 3: Setting up
Overview of the LHC Magnets other than the Main Dipoles
Siegel, N
2000-01-01
The Large Hadron Collider, due for commissioning in 2005, features a large and complex magnet system that includes about 3000 double aperture magnets and 5000 single aperture ones. Most of these magnets are super-conducting, using conductors made of NbTi alloy, with a coil bore of 56 mm and operating in a static bath of su-perfluid helium at 1.9 K, fully exploiting the conductor limit at these low temperatures. Only a few particular magnets will operate at 4.5 K. For special applications in the long straight sections and for beam injection and ex-traction, highly specialised room temperature magnets are used. The paper discusses the underlying concepts, which lead to the design and layout of the interaction region magnets, required to obtain the very demanding beam parameters at the four main LHC experiments. The focus will then be on the magnetic elements of matching re-gions, dispersion suppressors and main arcs, with a dis-cussion of the functionality of the different magnet fami-lies. The report will be c...
Random vector and matrix and vector theories: a renormalization group approach
Jean Zinn-Justin
2014-10-07
Random matrices in the large N expansion and the so-called double scaling limit can be used as toy models for quantum gravity: 2D quantum gravity coupled to conformal matter. This has generated a tremendous expansion of random matrix theory, tackled with increasingly sophisticated mathematical methods and number of matrix models have been solved exactly. However, the somewhat paradoxical situation is that either models can be solved exactly or little can be said. Since the solved models display critical points and universal properties, it is tempting to use renormalization group ideas to determine universal properties, without solving models explicitly. Initiated by Br\\'ezin and Zinn-Justin, the approach has led to encouraging results, first for matrix integrals and then quantum mechanics with matrices, but has not yet become a universal tool as initially hoped. In particular, general quantum field theories with matrix fields require more detailed investigations. To better understand some of the encountered difficulties, we first apply analogous ideas to the simpler O(N) symmetric vector models, models that can be solved quite generally in the large N limit. Unlike other attempts, our method is a close extension of Br\\'ezin and Zinn-Justin. Discussing vector and matrix models with similar approximation scheme, we notice that in all cases (vector and matrix integrals, vector and matrix path integrals in the local approximation), at leading order, non-trivial fixed points satisfy the same universal algebraic equation, and this is the main result of this work. However, its precise meaning and role have still to be better understood.
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.
Wang, Zhiyuan; Sun, Z. Z.
2014-02-14
The stationary-state solutions of magnetization dynamics under a spin-polarized current that was polarized in an arbitrary direction were investigated by solving the Landau-Lifshitz-Gilbert-Slonczewski equation for a single-domain magnet. Taking into consideration the uniaxial magnetic anisotropy, the equilibrium directions of the magnetization vectors were analytically obtained by solving an algebraic cubic equation. It was found that one to three pairs of magnetization equilibrium states existed, depending on the current intensity and the direction of the spin polarization. By numerically analyzing the stabilities of these equilibrium states, the threshold switching current for the reversing the magnetic vector was obtained under different current polarization configurations, which may be useful for use in future spintronics devices.
Iterative Water-filling for Gaussian Vector Multiple Access Channels
Li, Tiffany Jing
Iterative Water-filling for Gaussian Vector Multiple Access Channels W. Yu, W. Rhee, S. Boyd, and J. Cioffi Zhenlei Shen Lehigh University March 29, 2005 Zhenlei Shen (Lehigh) Iterative Water-filling for Gaussian Vector Multiple Access ChannelsMarch 29, 2005 1 / 13 #12;1 Quick Review 2 Iterative Water
The role of vector fields in modified gravity scenarios
Tasinato, Gianmassimo; Koyama, Kazuya; Khosravi, Nima E-mail: kazuya.koyama@port.ac.uk
2013-11-01
Gravitational vector degrees of freedom typically arise in many examples of modified gravity models. We start to systematically explore their role in these scenarios, studying the effects of coupling gravitational vector and scalar degrees of freedom. We focus on set-ups that enjoy a Galilean symmetry in the scalar sector and an Abelian gauge symmetry in the vector sector. These symmetries, together with the requirement that the equations of motion contain at most two space-time derivatives, only allow for a small number of operators in the Lagrangian for the gravitational fields. We investigate the role of gravitational vector fields for two broad classes of phenomena that characterize modified gravity scenarios. The first is self-acceleration: we analyze in general terms the behavior of vector fluctuations around self-accelerating solutions, and show that vanishing kinetic terms of vector fluctuations lead to instabilities on cosmological backgrounds. The second phenomenon is the screening of long range fifth forces by means of Vainshtein mechanism. We show that if gravitational vector fields are appropriately coupled to a spherically symmetric source, they can play an important role for defining the features of the background solution and the scale of the Vainshtein radius. Our general results can be applied to any concrete model of modified gravity, whose low-energy vector and scalar degrees of freedom satisfy the symmetry requirements that we impose.
SUPPORT VECTOR MACHINE CLASSIFICATION 18th July, 2006
Wand, Matt
of research is computer- aided mail sorting. Figure 1 shows 3 sets of handwritten digits. Suppose that someSUPPORT VECTOR MACHINE CLASSIFICATION M.P. Wand1 18th July, 2006 Support vector machines emerged in the mid-1990s as a flexible and powerful means of classification. Classification is a very old problem
Multi-Target Vectorization With MTPS C++ Generic Library
Vialle, Stéphane
-based design for scientific applications. Such generic libraries allow to define Domain Specific EmbeddedMulti-Target Vectorization With MTPS C++ Generic Library Wilfried Kirschenmann1,3 , Laurent Plagne1 Abstract. This article introduces a C++ template library dedicated at vectorizing algorithms for different
A Clustering Approach for Protecting GIS Vector Data
Cocea, Mihaela
A Clustering Approach for Protecting GIS Vector Data Ahmed Abubahia and Mihaela Cocea School.abubahia,mihaela.cocea}@port.ac.uk Abstract. The availability of Geographic Information System (GIS) data has increased in recent years some vertices from GIS vector data) and interpolation (adding new vertices to GIS data) modifications
An Adaptive Multidimensional Integration Routine for a Vector of Integrals.
Genz, Alan
NDIM .....dx1 where FUNSUB is a vector of integrands of length NUMFUN and H is a NDIM dimensional hyper algorithm for the numerical integration of a vector of integrand functions over a hyper-rectangular region dimensional degree 13 rule. Â· D113RE is a three dimensional degree 11 rule. Â· D09HRE is a degree 9 rule
Sparse Online Greedy Support Vector Yaakov Engel1
Meir, Ron
problems. 1 Introduction Kernel machines have become by now a standard tool in the arsenal of MachineSparse Online Greedy Support Vector Regression Yaakov Engel1 , Shie Mannor2 and Ron Meir2 1 Center to kernel machines and in recent years focused on Support Vector Machines (SVMs) [13]. A basic idea behind
The toric h-vectors of partially ordered sets
Bayer, Margaret M.; Ehrenborg, R.
2000-01-01
An explicit formula for the toric h-vector of an Eulerian poset in terms of the cd-index is developed using coalgebra techniques. The same techniques produce a formula in terms of the ag h-vector. For this, another proof based on Fine's algorithm...
Semi--vector spaces and units of measurement
Josef Janyška; Marco Modugno; Raffaele Vitolo
2007-10-05
This paper is aimed at introducing an algebraic model for physical scales and units of measurement. This goal is achieved by means of the concept of ``positive space'' and its rational powers. Positive spaces are 1-dimensional ``semi-vector spaces'' without the zero vector. A direct approach to this subject might be sufficient. On the other hand, a broader mathematical understanding requires the notions of sesqui- and semi-tensor products between semi-vector spaces and vector spaces. So, the paper is devoted to an original contribution to the algebraic theory of semi-vector spaces, to the algebraic analysis of positive spaces and, eventually, to the algebraic model of physical scales and units of measurement in terms of positive spaces.
Video-rate terahertz electric-field vector imaging
Takai, Mayuko; Takeda, Masatoshi; Sasaki, Manabu; Tachizaki, Takehiro; Yasumatsu, Naoya; Watanabe, Shinichi, E-mail: watanabe@phys.keio.ac.jp [Department of Physics, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama, Kanagawa 223-8522 (Japan)
2014-10-13
We present an experimental setup to dramatically reduce a measurement time for obtaining spatial distributions of terahertz electric-field (E-field) vectors. The method utilizes the electro-optic sampling, and we use a charge-coupled device to detect a spatial distribution of the probe beam polarization rotation by the E-field-induced Pockels effect in a ?110?-oriented ZnTe crystal. A quick rotation of the ZnTe crystal allows analyzing the terahertz E-field direction at each image position, and the terahertz E-field vector mapping at a fixed position of an optical delay line is achieved within 21 ms. Video-rate mapping of terahertz E-field vectors is likely to be useful for achieving real-time sensing of terahertz vector beams, vector vortices, and surface topography. The method is also useful for a fast polarization analysis of terahertz beams.
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
Magnetic Probe to Study Plasma Jets for Magneto-Inertial Fusion
Martens, Daniel; Hsu, Scott C.
2012-08-16
A probe has been constructed to measure the magnetic field of a plasma jet generated by a pulsed plasma rail-gun. The probe consists of two sets of three orthogonally-oriented commercial chip inductors to measure the three-dimensional magnetic field vector at two separate positions in order to give information about the magnetic field evolution within the jet. The strength and evolution of the magnetic field is one of many factors important in evaluating the use of supersonic plasma jets for forming imploding spherical plasma liners as a standoff driver for magneto-inertial fusion.
Anisotropic magnetization and transport properties of RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm)
Myers, Kenneth D.
1999-11-08
This study of the RAgSb{sub 2} series of compounds arose as part of an investigation of rare earth intermetallic compounds containing antimony with the rare earth in a position with tetragonal point symmetry. Materials with the rare earth in a position with tetragonal point symmetry frequently manifest strong anisotropies and rich complexity in the magnetic properties, and yet are simple enough to analyze. Antimony containing intermetallic compounds commonly possess low carrier densities and have only recently been the subject of study. Large single grain crystals were grown of the RAgSb{sub 2} (R=Y, La-Nd, Sm, Gd-Tm) series of compounds out of a high temperature solution. This method of crystal growth, commonly known as flux growth is a versatile method which takes advantage of the decreasing solubility of the target compound with decreasing temperature. Overall, the results of the crystal growth were impressive with the synthesis of single crystals of LaAgSb{sub 2} approaching one gram. However, the sample yield diminishes as the rare earth elements become smaller and heavier. Consequently, no crystals could be grown with R=Yb or Lu. Furthermore, EuAgSb{sub 2} could not be synthesized, likely due to the divalency of the Eu ion. For most of the RAgSb{sub 2} compounds, strong magnetic anisotropies are created by the crystal electric field splitting of the Hund's rule ground state. This splitting confines the local moments to lie in the basal plane (easy plane) for the majority of the members of the series. Exceptions to this include ErAgSb{sub 2} and TmAgSb{sub 2}, which have moments along the c-axis (easy axis) and CeAgSb{sub 2}, which at intermediate temperatures has an easy plane, but exchange coupling at low temperatures is anisotropic with an easy axis. Additional anisotropy is also observed within the basal plane of DyAgSb{sub 2}, where the moments are restricted to align along one of the {l_angle}110{r_angle} axes. Most of the RAgSb{sub 2} compounds containing magnetic rare earths, antiferromagnetically ordered at low temperatures. The ordering temperatures of these compounds are approximately proportional to the de Gennes factor, which suggests that the RKKY interaction is the dominant exchange interaction between local moments. Although metamagnetic transitions were observed in many members of the series, the series of sharp step-like transitions in DyAgSb{sub 2} are impressive. In this compound, up to 11 different magnetic states are stable depending on the magnitude and direction of the applied field. The saturated magnetization of these states and the critical fields needed to induce a phase transition vary with the direction of the applied field. Through detailed study of the angular dependence of the magnetization and critical fields, the net distribution of magnetic moments was determined for most, of the metamagnetic states. In DyAgSb{sub 2}, the crystal electric field (CEF) splitting of the Hund's rule ground state creates a strong anisotropy where the local Dy{sup 3+} magnetic moments are constrained to one of the equivalent {l_angle}110{r_angle} directions within the basal plane. The four position clock model was introduced to account for this rich metamagnetic system. Within this model, the magnetic moments are constrained to one of four equivalent orientations within the basal plane and interactions are calculated for up third nearest neighbors. The theoretical phase diagram, generated from the coupling constants is in excellent agreement with the experimental phase diagram. Further investigation of this compound using magnetic X-ray or neutron diffraction would be extremely useful to verify the net distributions of moments and determine the wave vectors of each of the ordered states.
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Up: APS Storage Ring Parameters Previous: Longitudinal bunch profile and Magnets and Power Supplies Dipole Magnets and Power Supplies Value Dipole Number 80+1 No. of power...
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
Statistical performance of support vector machines
Blanchard, Gilles; Massart, Pascal
2008-01-01
The support vector machine (SVM) algorithm is well known to the computer learning community for its very good practical results. The goal of the present paper is to study this algorithm from a statistical perspective, using tools of concentration theory and empirical processes. Our main result builds on the observation made by other authors that the SVM can be viewed as a statistical regularization procedure. From this point of view, it can also be interpreted as a model selection principle using a penalized criterion. It is then possible to adapt general methods related to model selection in this framework to study two important points: (1) what is the minimum penalty and how does it compare to the penalty actually used in the SVM algorithm; (2) is it possible to obtain ``oracle inequalities'' in that setting, for the specific loss function used in the SVM algorithm? We show that the answer to the latter question is positive and provides relevant insight to the former. Our result shows that it is possible to...
T. Sumikama; K. Matsuta; T. Nagatomo; M. Ogura; T. Iwakoshi; Y. Nakashima; H. Fujiwara; M. Fukuda; M. Mihara; K. Minamisono; T. Yamaguchi; T. Minamisono
2011-05-09
The beta-ray angular correlations for the spin alignments of 8Li and 8B have been observed in order to test the conserved vector current (CVC) hypothesis. The alignment correlation terms were combined with the known beta-alpha-angular correlation terms to determine all the matrix elements contributing to the correlation terms. The weak magnetism term, 7.5\\pm0.2, deduced from the beta-ray correlation terms was consistent with the CVC prediction 7.3\\pm0.2, deduced from the analog-gamma-decay measurement based on the CVC hypothesis. However, there was no consistent CVC prediction for the second-forbidden term associated with the weak vector current. The experimental value for the second-forbidden term was 1.0 \\pm 0.3, while the CVC prediction was 0.1 \\pm 0.4 or 2.1 \\pm 0.5.
Low-lying neutron fp-shell intruder states in Ne-27
Wilson, Graham Wallace; Brown, S. M.; Catford, W. N.; Thomas, J. S.; Ferná ndez-Domí nguez, B.; Orr, N. A.; Labiche, M.; Rejmund, M.; Achouri, N. L.; Al Falou, H.; Ashwood, N. I.; Beaumel, D.; Blumenfeld, Y.; Brown, B. A.; Chapman, R.
2012-01-23
in TIARA and the recoil in VAMOS was compared to that of the incident beam. For 27Ne? ?26Ne + n, the momentum of the undetected neutron was sufficiently well defined to resolve these events from elastic scattering [23]. The energies of protons populating...RAPID COMMUNICATIONS PHYSICAL REVIEW C 85, 011302(R) (2012) Low-lying neutron f p-shell intruder states in 27Ne S. M. Brown,1 W. N. Catford,1 J. S. Thomas,1 B. Ferna´ndez-Dom?´nguez,2,3 N. A. Orr,2 M. Labiche,4 M. Rejmund,5 N. L. Achouri,2 H. Al...
A thermal coherent state defined with the Lie-Trotter product formula
Hiroo Azuma; Masashi Ban
2015-07-11
In this paper, we investigate a thermal coherent state defined with the Lie-Trotter product formula under the formalism of the thermo field dynamics. In the definition of our thermal coherent state, we treat the thermalizing operator and the displacement operator symmetrically. We examine its uncertainty relation and quasiprobability distributions. Although this thermal coherent state is equivalent to the conventional ones except for different parameterizations and a phase factor, it is convenient for describing an experimental setup of the optical parametric oscillator laser.
Origin of Low-Lying Enhanced E1 Strength in Rare-Earth Nuclei
M. Spieker; S. Pascu; A. Zilges; F. Iachello
2015-05-17
The experimental $E1$ strength distribution below 4 MeV in rare-earth nuclei suggests a local breaking of isospin symmetry. In addition to the octupole states, additional $1^-$ states with enhanced E1 strength have been observed in rare-earth nuclei by means of ($\\gamma,\\gamma'$) experiments. By reproducing the experimental results, the spdf interacting boson model calculations provide further evidence for the formation of an $\\alpha$ cluster in medium-mass nuclei and might provide a new understanding of the origin of low-lying E1 strength.
Matrix elements for type 1 unitary irreducible representations of the Lie superalgebra gl(m|n)
Gould, Mark D.; Isaac, Phillip S.; Werry, Jason L.
2014-01-15
Using our recent results on eigenvalues of invariants associated to the Lie superalgebra gl(m|n), we use characteristic identities to derive explicit matrix element formulae for all gl(m|n) generators, particularly non-elementary generators, on finite dimensional type 1 unitary irreducible representations. We compare our results with existing works that deal with only subsets of the class of type 1 unitary representations, all of which only present explicit matrix elements for elementary generators. Our work therefore provides an important extension to existing methods, and thus highlights the strength of our techniques which exploit the characteristic identities.
Couper, Sara-Louise
2011-06-29
This study investigated the claim of Neuro-Linguistic Programming (NLP) practitioners that eye movements to the upper right (UR) indicate a person is lying and eye movements to the upper left (UL) indicate a person is ...
Bifurcation values for a family of planar vector fields of degree five
García-Saldaña, J D; Giacomini, H
2012-01-01
We study the number of limit cycles and the bifurcation diagram in the Poincar\\'{e} sphere of a one-parameter family of planar differential equations of degree five $\\dot {\\bf x}=X_b({\\bf x})$ which has been already considered in previous papers. We prove that there is a value $b^*>0$ such that the limit cycle exists only when $b\\in(0,b^*)$ and that it is unique and hyperbolic by using a rational Dulac function. Moreover we provide an interval of length 27/1000 where $b^*$ lies. As far as we know the tools used to determine this interval are new and are based on the construction of algebraic curves without contact for the flow of the differential equation. These curves are obtained using analytic information about the separatrices of the infinite critical points of the vector field. To prove that the Bendixson-Dulac Theorem works we develop a method for studying whether one-parameter families of polynomials in two variables do not vanish based on the computation of the so called double discriminant.
An XMRV Derived Retroviral Vector as a Tool for Gene Transfer
Cervantes-Garcia, Daniel; Rojas-Martinez, Augusto; Camerini, David
2011-01-01
Garcia et al. : An XMRV Derived Retroviral Vector as a ToolREPORT Open Access An XMRV Derived Retroviral Vector as ain vivo. Many retroviral vectors are derived from the mouse
PROTOSTELLAR DISK FORMATION ENABLED BY WEAK, MISALIGNED MAGNETIC FIELDS
Krumholz, Mark R.; Crutcher, Richard M.; Hull, Charles L. H.
2013-04-10
The gas from which stars form is magnetized, and strong magnetic fields can efficiently transport angular momentum. Most theoretical models of this phenomenon find that it should prevent formation of large (>100 AU), rotationally supported disks around most protostars, even when non-ideal magnetohydrodynamic (MHD) effects that allow the field and gas to decouple are taken into account. Using recent observations of magnetic field strengths and orientations in protostellar cores, we show that this conclusion is incorrect. The distribution of magnetic field strengths is very broad, and alignments between fields and angular momentum vectors within protostellar cores are essentially random. By combining the field strength and misalignment data with MHD simulations showing that disk formation is expected for both weak and misaligned fields, we show that these observations imply that we should expect disk fractions of {approx}10%-50% even when protostars are still deeply embedded in their parent cores, and even if the gas is governed by ideal MHD.
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.
Energy momentum flows for the massive vector field
George Horton; Chris Dewdney
2006-09-26
We present a causal trajectory interpretation for the massive vector field, based on the flows of rest energy and a conserved density defined using the time-like eigenvectors and eigenvalues of the stress-energy-momentum tensor. This work extends our previous work which used a similar procedure for the scalar field. The massive, spin-one, complex vector field is discussed in detail and solutions are classified using the Pauli-Lubanski spin vector. The flows of energy-momentum are illustrated in a simple example of standing waves in a plane.
Characterizing cluster morphology using vector-valued Minkowski functionals
Claus Beisbart; Thomas Buchert
1997-11-04
The morphology of galaxy clusters is quantified using Minkowski functionals, especially the vector-valued ones, which contain directional information and are related to curvature centroids. The asymmetry of clusters and the amount of their substructure can be characterized in a unique way using these measures. -- We briefly introduce vector-valued Minkowski functionals (also known as Querma\\ss vectors) and suggest their application to cluster data in terms of a morphological characterization of excursion sets. Furthermore, we develop robust structure functions which describe the dynamical state of a cluster and study the evolution of clusters using numerical simulations.
On the stability and causality of scalar-vector theories
Fleury, Pierre; Pitrou, Cyril; Uzan, Jean-Philippe; Almeida, Juan P. Beltrán E-mail: juanpbeltran@uan.edu.co E-mail: uzan@iap.fr
2014-11-01
Various extensions of standard inflationary models have been proposed recently by adding vector fields. Because they are generally motivated by large-scale anomalies, and the possibility of statistical anisotropy of primordial fluctuations, such models require to introduce non-standard couplings between vector fields on the one hand, and either gravity or scalar fields on the other hand. In this article, we study models involving a vector field coupled to a scalar field. We derive restrictive necessary conditions for these models to be both stable (Hamiltonian bounded by below) and causal (hyperbolic equations of motion)
Optimization code with weighting function for the reconstruction of coronal magnetic fields
T. Wiegelmann
2008-02-01
We developed a code for the reconstruction of nonlinear force-free and non-force-free coronal magnetic fields. The 3D magnetic field is computed numerically with the help of an optimization principle. The force-free and non-force-free codes are compiled in one program. The force-free approach needs photospheric vector magnetograms as input. The non-force-free code additionally requires the line-of-sight integrated coronal density distribution in combination with a tomographic inversion code. Previously the optimization approach has been used to compute magnetic fields using all six boundaries of a computational box. Here we extend this method and show how the coronal magnetic field can be reconstructed only from the bottom boundary, where the boundary conditions are measured with vector magnetographs. The program is planed for use within the Stereo mission.
Combined Electric and Magnetic Aharonov-Bohm Effects
Samuel Marcovitch; Yakir Aharonov; Tirza Kaufferr; Benni Reznik
2007-09-11
It is well-known that the electric and magnetic Aharonov-Bohm effects may be formally described on equal footing using the four-vector potential in a relativistic framework. We propose an illustrative manifestation of both effects in a single configuration, in which the specific path of the charged particle determines the weight of the electric and magnetic acquired relative phases. The phases can be distinctively obtained in the Coulomb gauge. The scheme manifests the pedagogical lesson that though each of the relative phases is gauge-dependent their sum is gauge-invariant.
Massive photons and Dirac monopoles: electric condensate and magnetic confinement
M. S. Guimaraes; R. Rougemont; C. Wotzasek; C. A. D. Zarro
2013-05-13
We use the generalized Julia-Toulouse approach (GJTA) for condensation of topological currents (charges or defects) to argue that massive photons can coexist consistently with Dirac monopoles. The Proca theory is obtained here via GJTA as a low energy effective theory describing an electric condensate and the mass of the vector boson is responsible for generating a Meissner effect which confines the magnetic defects in monopole-antimonopole pairs connected by physical open magnetic vortices described by Dirac brane invariants, instead of Dirac strings.
3D reconstruction of tensors and vectors
Defrise, Michel; Gullberg, Grant T.
2005-02-17
Here we have developed formulations for the reconstruction of 3D tensor fields from planar (Radon) and line-integral (X-ray) projections of 3D vector and tensor fields. Much of the motivation for this work is the potential application of MRI to perform diffusion tensor tomography. The goal is to develop a theory for the reconstruction of both Radon planar and X-ray or line-integral projections because of the flexibility of MRI to obtain both of these type of projections in 3D. The development presented here for the linear tensor tomography problem provides insight into the structure of the nonlinear MRI diffusion tensor inverse problem. A particular application of tensor imaging in MRI is the potential application of cardiac diffusion tensor tomography for determining in vivo cardiac fiber structure. One difficulty in the cardiac application is the motion of the heart. This presents a need for developing future theory for tensor tomography in a motion field. This means developing a better understanding of the MRI signal for diffusion processes in a deforming media. The techniques developed may allow the application of MRI tensor tomography for the study of structure of fiber tracts in the brain, atherosclerotic plaque, and spine in addition to fiber structure in the heart. However, the relations presented are also applicable to other fields in medical imaging such as diffraction tomography using ultrasound. The mathematics presented can also be extended to exponential Radon transform of tensor fields and to other geometric acquisitions such as cone beam tomography of tensor fields.
Adiabatic expansion and magnetic fields in AGN jets
A. B. Pushkarev; Y. Y. Kovalev; A. P. Lobanov
2008-12-25
Results of high-resolution simultaneous multi-frequency 8.1-15.4 GHz VLBA polarimetric observations of relativistic jets in active galactic nuclei (the MOJAVE-2 project) are analyzed. We compare characteristics of VLBI features with jet model predictions and test if adiabatic expansion is a dominating mechanism for the evolution of relativistic shocks in parsec-scale AGN jets. We also discuss magnetic field configuration, both predicted by the model and deduced from electric vector position angle measurements.
Nonlinear force-free modeling of the solar coronal magnetic field
T. Wiegelmann
2008-01-18
The coronal magnetic field is an important quantity because the magnetic field dominates the structure of the solar corona. Unfortunately direct measurements of coronal magnetic fields are usually not available. The photospheric magnetic field is measured routinely with vector magnetographs. These photospheric measurements are extrapolated into the solar corona. The extrapolated coronal magnetic field depends on assumptions regarding the coronal plasma, e.g. force-freeness. Force-free means that all non-magnetic forces like pressure gradients and gravity are neglected. This approach is well justified in the solar corona due to the low plasma beta. One has to take care, however, about ambiguities, noise and non-magnetic forces in the photosphere, where the magnetic field vector is measured. Here we review different numerical methods for a nonlinear force-free coronal magnetic field extrapolation: Grad-Rubin codes, upward integration method, MHD-relaxation, optimization and the boundary element approach. We briefly discuss the main features of the different methods and concentrate mainly on recently developed new codes.
MAGNETIC FIELD IN THE ISOLATED MASSIVE DENSE CLUMP IRAS 20126+4104
Shinnaga, Hiroko; Phillips, Thomas G. [California Institute of Technology Submillimeter Observatory, 111 Nowelo Street, Hilo, HI 96720 (United States); Novak, Giles [Department of Physics and Astronomy, Northwestern University, 633 Clark Street Evanston, IL 60208 (United States); Vaillancourt, John E. [Stratospheric Observatory for Infrared Astronomy, Universities Space Research Association, NASA Ames Research Center, Moffet Field, CA 94035 (United States); Machida, Masahiro N. [Department of Earth and Planetary Sciences, Faculty of Sciences, Kyushu University, 6-10-1 Hakozaki, Higashi-ku, Fukuoka 812-8581 (Japan); Kataoka, Akimasa [Department of Astronomy, Kyoto University, Kitashirakawa-Oiwake-cho, Sakyo-ku, Kyoto 606-8502 (Japan); Tomisaka, Kohji [National Astronomical Observatory of Japan and Department of Astronomy, School of Physical Sciences, Graduate University for Advanced Studies (SOKENDAI), Osawa 2-21-1, Mitaka, Tokyo 181-8588 (Japan); Davidson, Jacqueline; Houde, Martin [School of Physics, University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Perth (Australia); Dowell, C. Darren [Jet Propulsion Laboratory, California Institute of Technology, MS 169-506, 4800 Oak Grove Drive, Pasadena, CA 91109 (United States); Leeuw, Lerothodi [SETI Institute, 515 North Whisman Avenue, Mountain View, CA 94043 (United States)
2012-05-10
We measured polarized dust emission at 350 {mu}m toward the high-mass star-forming massive dense clump IRAS 20126+4104 using the SHARC II Polarimeter, SHARP, at the Caltech Submillimeter Observatory. Most of the observed magnetic field vectors agree well with magnetic field vectors obtained from a numerical simulation for the case when the global magnetic field lines are inclined with respect to the rotation axis of the dense clump. The results of the numerical simulation show that rotation plays an important role on the evolution of the massive dense clump and its magnetic field. The direction of the cold CO 1-0 bipolar outflow is parallel to the observed magnetic field within the dense clump as well as the global magnetic field, as inferred from optical polarimetry data, indicating that the magnetic field also plays a critical role in an early stage of massive star formation. The large-scale Keplerian disk of the massive (proto)star rotates in an almost opposite sense to the clump's envelope. The observed magnetic field morphology and the counterrotating feature of the massive dense clump system provide hints to constrain the role of magnetic fields in the process of high-mass star formation.
Coherent states, quantum gravity and the Born-Oppenheimer approximation, II: Compact Lie Groups
Stottmeister, Alexander
2015-01-01
In this article, the second of three, we discuss and develop the basis of a Weyl quantisation for compact Lie groups aiming at loop quantum gravity-type models. This Weyl quantisation may serve as the main mathematical tool to implement the program of space adiabatic perturbation theory in such models. As we already argued in our first article, space adiabatic perturbation theory offers an ideal framework to overcome the obstacles that hinder the direct implementation of the conventional Born-Oppenheimer approach in the canonical formulation of loop quantum gravity. Additionally, we conjecture the existence of a new form of the Segal-Bargmann-Hall "coherent state" transform for compact Lie groups $G$, which we prove for $G=U(1)^{n}$ and support by numerical evidence for $G=SU(2)$. The reason for conjoining this conjecture with the main topic of this article originates in the observation, that the coherent state transform can be used as a basic building block of a coherent state quantisation (Berezin quantisat...
Low-lying $?$ Baryons with spin 1/2 in Two-flavor Lattice QCD
Toru T. Takahashi; Makoto Oka
2010-02-10
Low-lying $\\Lambda$ baryons with spin 1/2 are analyzed in full (unquenched) lattice QCD. We construct $2 \\times 2$ cross correlators from flavor SU(3) "octet" and "singlet" baryon operators, and diagonalize them so as to extract information of two low-lying states for each parity. The two-flavor CP-PACS gauge configurations are used, which are generated in the renormalization-group improved gauge action and the ${\\mathcal O}(a)$-improved quark action. Three different $\\beta$'s, $\\beta = 1.80$, 1.95 and 2.10, are employed, whose corresponding lattice spacings are $a = 0.2150$, 0.1555 and 0.1076 fm. For each cutoff, we use four hopping parameters, ($\\kappa_{\\rm val}, \\kappa_{\\rm sea}$), which correspond to the pion masses ranging about from 500 MeV to 1.1 GeV. Results indicate that there are two negative-parity $\\Lambda$ states nearly degenerate at around 1.6 GeV, while no state as low as $\\Lambda (1405)$ is observed. By decomposing the flavor components of each state, we find that the lowest (1st-excited) negative-parity state is dominated by flavor-singlet (flavor-octet) component. We also discuss meson-baryon components of each state, which has drawn considerable attention in the context of multi-quark pictures of $\\Lambda (1405)$.
Low-lying positive-parity excited states of the nucleon
M. S. Mahbub; Alan Ó Cais; Waseem Kamleh; B. G. Lasscock; Derek B. Leinweber; Anthony G. Williams
2009-10-15
We present an overview of the correlation-matrix methods developed recently by the CSSM Lattice Collaboration for the isolation of excited states of the nucleon. Of particular interest is the first positive-parity excited-state of the nucleon known as the Roper resonance. Using eigenvectors of the correlation matrix we construct parity and eigenstate projected correlation functions which are analysed using standardized methods. The robust nature of this approach for extracting the eigenstate energies is presented. We report the importance of using a variety of source and sink smearings in achieving this. Ultimately the independence of the eigenstate energies from the interpolator basis is demonstrated. In particular we consider $4\\times 4$ correlation matrices built from a variety of interpolators and smearing levels. Using FLIC fermions to access the light quark mass regime, we explore the curvature encountered in the energy of the states as the chiral limit is approached. We report a low-lying Roper state contrasting earlier results using correlation matrices. To the best of our knowledge, this is the first time a low-lying Roper resonance has been found using correlation matrix methods. Finally, we present our results in the context of the Roper results reported by other groups.
Quantization maps, algebra representation, and non-commutative Fourier transform for Lie groups
Guedes, Carlos; Oriti, Daniele; Raasakka, Matti; LIPN, Institut Galilée, Université Paris-Nord, 99, av. Clement, 93430 Villetaneuse
2013-08-15
The phase space given by the cotangent bundle of a Lie group appears in the context of several models for physical systems. A representation for the quantum system in terms of non-commutative functions on the (dual) Lie algebra, and a generalized notion of (non-commutative) Fourier transform, different from standard harmonic analysis, has been recently developed, and found several applications, especially in the quantum gravity literature. We show that this algebra representation can be defined on the sole basis of a quantization map of the classical Poisson algebra, and identify the conditions for its existence. In particular, the corresponding non-commutative star-product carried by this representation is obtained directly from the quantization map via deformation quantization. We then clarify under which conditions a unitary intertwiner between such algebra representation and the usual group representation can be constructed giving rise to the non-commutative plane waves and consequently, the non-commutative Fourier transform. The compact groups U(1) and SU(2) are considered for different choices of quantization maps, such as the symmetric and the Duflo map, and we exhibit the corresponding star-products, algebra representations, and non-commutative plane waves.
New techniques for the scientific visualization of three-dimensional multi-variate and vector fields
Crawfis, R.A.
1995-10-01
Volume rendering allows us to represent a density cloud with ideal properties (single scattering, no self-shadowing, etc.). Scientific visualization utilizes this technique by mapping an abstract variable or property in a computer simulation to a synthetic density cloud. This thesis extends volume rendering from its limitation of isotropic density clouds to anisotropic and/or noisy density clouds. Design aspects of these techniques are discussed that aid in the comprehension of scientific information. Anisotropic volume rendering is used to represent vector based quantities in scientific visualization. Velocity and vorticity in a fluid flow, electric and magnetic waves in an electromagnetic simulation, and blood flow within the body are examples of vector based information within a computer simulation or gathered from instrumentation. Understand these fields can be crucial to understanding the overall physics or physiology. Three techniques for representing three-dimensional vector fields are presented: Line Bundles, Textured Splats and Hair Splats. These techniques are aimed at providing a high-level (qualitative) overview of the flows, offering the user a substantial amount of information with a single image or animation. Non-homogenous volume rendering is used to represent multiple variables. Computer simulations can typically have over thirty variables, which describe properties whose understanding are useful to the scientist. Trying to understand each of these separately can be time consuming. Trying to understand any cause and effect relationships between different variables can be impossible. NoiseSplats is introduced to represent two or more properties in a single volume rendering of the data. This technique is also aimed at providing a qualitative overview of the flows.
QCD description of backward vector meson hard electroproduction
B. Pire; K. Semenov-Tian-Shansky; L. Szymanowski
2015-03-10
We consider backward vector meson exclusive electroproduction off nucleons in the framework of collinear QCD factorization. Nucleon to vector meson transition distribution amplitudes arise as building blocks for the corresponding factorized amplitudes. In the near-backward kinematics, the suggested factorization mechanism results in the dominance of the transverse cross section of vector meson production ($\\sigma_T \\gg \\sigma_L$) and in the characteristic $1/Q^8$-scaling behavior of the cross section. We evaluate nucleon to vector meson TDAs in the cross-channel nucleon exchange model and present estimates of the differential cross section for backward $\\rho^0$, $\\omega$ and $\\phi$ meson production off protons. The resulting cross sections are shown to be measurable in the forthcoming JLab@12 GeV experiments.
3.3 Construction of vector edge elements
2011-10-05
Figure 3.1: Linear tetrahedral element. 3.3 Construction of vector edge elements. Let us first consider the linear tetrahedral element, as seen in Figure 3.1. Within.
Evaluating Aeolian Sand Transport Vectors In Dune Blowouts
Randolph, Janelle
2013-02-13
Grain size distribution is the reflection of the feedback between sediment transport system and morphologic change of beach systems. In this respect, early models suggest that grain size can be used to determine the transport vectors. However...
On the Capacity of Vector Gaussian Interference Channels Sriram Vishwanath
Jafar, Syed A.
On the Capacity of Vector Gaussian Interference Channels Sriram Vishwanath Electrical and Computer Engineering Univ. of Texas at Austin, Austin, TX 78712 e-mail: sriram@ece.utexas.edu Syed Ali Jafar Electrical
Viability of vector-tensor theories of gravity
Jose Beltran Jimenez; Antonio L. Maroto
2009-02-20
We present a detailed study of the viability of general vector-tensor theories of gravity in the presence of an arbitrary temporal background vector field. We find that there are six different classes of theories which are indistinguishable from General Relativity by means of local gravity experiments. We study the propagation speeds of scalar, vector and tensor perturbations and obtain the conditions for classical stability of those models. We compute the energy density of the different modes and find the conditions for the absence of ghosts in the quantum theory. We conclude that the only theories which can pass all the viability conditions for arbitrary values of the background vector field are not only those of the pure Maxwell type, but also Maxwell theories supplemented with a (Lorentz type) gauge fixing term.
Quantum Support Vector Machine for Big Data Classification
Mohseni, Masoud
Supervised machine learning is the classification of new data based on already classified training examples. In this work, we show that the support vector machine, an optimized binary classifier, can be implemented on a ...
Interference in Exclusive Vector Meson Production in Heavy Ion Collisions
Spencer R. Klein; Joakim Nystrand
1999-09-03
Photons emitted from the electromagnetic fields of relativistic heavy ions can fluctuate into quark anti-quark pairs and scatter from a target nucleus, emerging as vector mesons. These coherent interactions are identifiable by final states consisting of the two nuclei and a vector meson with a small transverse momentum. The emitters and targets can switch roles, and the two possibilities are indistinguishable, so interference may occur. Vector mesons are negative parity so the amplitudes have opposite signs. When the meson transverse wavelength is larger than the impact parameter, the interference is large and destructive. The short-lived vector mesons decay before amplitudes from the two sources can overlap, and so cannot interfere directly. However, the decay products are emitted in an entangled state, and the interference depends on observing the complete final state. The non-local wave function is an example of the Einstein-Podolsky-Rosen paradox.
Agilent E8267D PSG Vector Signal Generator
Anlage, Steven
Agilent E8267D PSG Vector Signal Generator Data Sheet The Agilent E8267D is a fully synthesized signal generator with high output power, low phase noise, and I/Q modulation capability. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15 Internal pulse generator
The Variable Vector Countermeasure Suit for space habitation and exploration
Vasquez, Rebecca (Rebecca Ann)
2014-01-01
The Variable Vector Countermeasure Suit (V2Suit) is a countermeasure suit for sensorimotor adaptation and musculoskeletal deconditioning in microgravity. The V2suit will consist of modules containing arrays of control ...
Particle Size Classification of Glass Particles Using Aerodynamic Jet Vectoring
Smith, Barton L.
Particle Size Classification of Glass Particles Using Aerodynamic Jet Vectoring Zachary E. Humes blowing and suction control flowsflows that are a fraction of the jet flow rateto sharply change
Highly parallel vector visualization using line integral convolution
Cabral, B.; Leedom, C.
1995-12-01
Line Integral Convolution (LIC) is an effective imaging operator for visualizing large vector fields. It works by blurring an input image along local vector field streamlines yielding an output image. LIC is highly parallelizable because it uses only local read-sharing of input data and no write-sharing of output data. Both coarse- and fine-grained implementations have been developed. The coarse-grained implementation uses a straightforward row-tiling of the vector field to parcel out work to multiple CPUs. The fine-grained implementation uses a series of image warps and sums to compute the LIC algorithm across the entire vector field at once. This is accomplished by novel use of high-performance graphics hardware texture mapping and accumulation buffers.
Jiang, Chaowei
2015-01-01
In the solar corona, magnetic flux rope is believed to be a fundamental structure accounts for magnetic free energy storage and solar eruptions. Up to the present, the extrapolation of magnetic field from boundary data is the primary way to obtain fully three-dimensional magnetic information of the corona. As a result, the ability of reliable recovering coronal magnetic flux rope is important for coronal field extrapolation. In this paper, our coronal field extrapolation code (CESE-MHD-NLFFF, Jiang & Feng 2012) is examined with an analytical magnetic flux rope model proposed by Titov & Demoulin (1999), which consists of a bipolar magnetic configuration holding an semi-circular line-tied flux rope in force-free equilibrium. By using only the vector field in the bottom boundary as input, we test our code with the model in a representative range of parameter space and find that the model field is reconstructed with high accuracy. Especially, the magnetic topological interfaces formed between the flux rop...
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Zhu, S.; Cai, Y.; Rote, D.M.; Chen, S.S.
1998-01-01
Magnetic damping is one of the important parameters that control the response and stability of maglev systems. An experimental study to measure magnetic damping directly is presented. A plate attached to a permanent magnet levitated on a rotating drum was tested to investigate the effect of various parameters, such as conductivity, gap, excitation frequency, and oscillation amplitude, on magnetic damping. The experimental technique is capable of measuring all of the magnetic damping coefficients, some of which cannot be measured indirectly.
Study of Vector Boson Fusion Higgs in Atlas-LHC
Dimitris Varouchas
2008-05-26
Within the framework of Standard Model, the production mode of Higgs boson through the fusion of the vector bosons $W$ or $Z$ (Vector Boson Fusion) is one of the most important production mechanisms, providing a specific detection signature. A detailed study regarding this issue is being undergone for ATLAS detector in LHC and some general features of this analysis are being presented in this note emphasizing in the study of Central Jet Veto.
Flatau, Alison B.
-D material properties under varied applied magnetic field levels Marcelo J. Dapino, Frederick T. Calkins An experimental approach is used to identify Terfenol-D material properties under magnetic bias and mechanical, and on the theory of vector impedance and admittance analysis. The material properties being investigated, measured
MAGNETIC BLOCH FUNCTIONS AND VECTOR BUNDLES. TYPICAL DISPERSION LAWS AND THEIR QUANTUM
Novikov, Sergei Petrovich
. The Hamiltonian in this case is the Pauli operator (1) H0 = - 1 2 x - ieA1 2 - 1 2 y - ieA2 2 + e3B; here = m
Magnetic Landscape of Sun's Polar Region
S. Tsuneta; K. Ichimoto; Y. Katsukawa; B. W. Lites; K. Matsuzaki; S. Nagata; D. Orozco Suarez; T. Shimizu; M. Shimojo; R. A. Shine; Y. Suematsu; T. K. Suzuki; T. D. Tarbell; A. M. Title
2008-08-08
We present the magnetic landscape of the polar region of the Sun that is unprecedented in terms of high spatial resolution, large field of view, and polarimetric precision. These observations were carried out with the Solar Optical Telescope aboard \\emph{Hinode}. Using a Milne-Eddington inversion, we found many vertically-oriented magnetic flux tubes with field strength as strong as 1 kG that are scattered in latitude between 70-90 degree. They all have the same polarity, consistent with the global polarity of the polar region. The field vectors were observed to diverge from the center of the flux elements, consistent with a view of magnetic fields that expand and fan out with height. The polar region is also covered with ubiquitous horizontal fields. The polar regions are the source of the fast solar wind channelled along unipolar coronal magnetic fields whose photospheric source is evidently rooted in the strong field, vertical patches of flux. We conjecture that vertical flux tubes with large expansion around the photosphere-corona boundary serve as efficient chimneys for Alfven waves that accelerate the solar wind.
Predissociation of high-lying Rydberg states of molecular iodine via ion-pair states
Bogomolov, Alexandr S. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation)] [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Grüner, Barbara; Mudrich, Marcel [Physikalisches Institut, Universität Freiburg, D-79104 Freiburg (Germany)] [Physikalisches Institut, Universität Freiburg, D-79104 Freiburg (Germany); Kochubei, Sergei A. [Institute of Semiconductor Physics, ac. Lavrent'yev ave., 13, Novosibirsk 630090 (Russian Federation)] [Institute of Semiconductor Physics, ac. Lavrent'yev ave., 13, Novosibirsk 630090 (Russian Federation); Baklanov, Alexey V. [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation) [Institute of Chemical Kinetics and Combustion, Institutskaya Str. 3, Novosibirsk 630090 (Russian Federation); Novosibirsk State University, Pirogova Str. 2, Novosibirsk 630090 (Russian Federation)
2014-03-28
Velocity map imaging of the photofragments arising from two-photon photoexcitation of molecular iodine in the energy range 73?500–74?500 cm{sup ?1} covering the bands of high-lying gerade Rydberg states [{sup 2}?{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}?{sub 1/2}]{sub c}6d;2{sub g} has been applied. The ion signal was dominated by the atomic fragment ion I{sup +}. Up to 5 dissociation channels yielding I{sup +} ions with different kinetic energies were observed when the I{sub 2} molecule was excited within discrete peaks of Rydberg states and their satellites in this region. One of these channels gives rise to images of I{sup +} and I{sup ?} ions with equal kinetic energy indicating predissociation of I{sub 2} via ion-pair states. The contribution of this channel was up to about 50% of the total I{sup +} signal. The four other channels correspond to predissociation via lower lying Rydberg states giving rise to excited iodine atoms providing I{sup +} ions by subsequent one-photon ionization by the same laser pulse. The ratio of these channels varied from peak to peak in the spectrum but their total ionic signal was always much higher than the signal of (2 + 1) resonance enhanced multi-photon ionization of I{sub 2}, which was previously considered to be the origin of ionic signal in this spectral range. The first-tier E0{sub g}{sup +} and D{sup ?}2{sub g} ion-pair states are concluded to be responsible for predissociation of Rydberg states [{sup 2}?{sub 1/2}]{sub c}6d;0{sub g}{sup +} and [{sup 2}?{sub 1/2}]{sub c}6d;2{sub g}, respectively. Further predissociation of these ion-pair states via lower lying Rydberg states gives rise to excited I(5s{sup 2}5p{sup 4}6s{sup 1}) atoms responsible for major part of ion signal. The isotropic angular distribution of the photofragment recoil directions observed for all channels indicates that the studied Rydberg states are long-lived compared with the rotational period of the I{sub 2} molecule.
Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets
2010-10-01
Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.
Nesterenko, A V
2015-01-01
The dispersive approach to QCD, which properly embodies the intrinsically nonperturbative constraints originating in the kinematic restrictions on relevant physical processes and extends the applicability range of perturbation theory towards the infrared domain, is briefly overviewed. The study of OPAL (update 2012) and ALEPH (update 2014) experimental data on inclusive tau lepton hadronic decay in vector and axial-vector channels within dispersive approach is presented.
Szabados, Barna
Permanent Magnet Synchronous Machines Abstract: An experimental investigation is conducted to determine the behaviour of brushless PM synchronous machine parameters in the high speed flux weakening operating range synchronous machines. Special computer assisted measuring techniques are employed using an experimental vector
Dual attitude and parameter estimation of passively magnetically stabilized nano satellites$
panels. By using the existing solar panels, no additional components are being added to the spacecraft, and no additional mass, volume or power budget is being used. From differential solar panel currents, an estimate of the magnetic materials using only a measurement of the solar vector. The estimation technique is applied
Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)
2006-11-14
A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.
Magnetic switch coupling to synchronize magnetic modulators
Reed, Kim W. (Albuquerque, NM); Kiekel, Paul (Albuquerque, NM)
1999-01-01
Apparatus for synchronizing the output pulses from a pair of magnetic switches. An electrically conductive loop is provided between the pair of switches with the loop having windlings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself.
Magnetic switch coupling to synchronize magnetic modulators
Reed, K.W.; Kiekel, P.
1999-04-27
Apparatus for synchronizing the output pulses from a pair of magnetic switches is disclosed. An electrically conductive loop is provided between the pair of switches with the loop having windings about the core of each of the magnetic switches. The magnetic coupling created by the loop removes voltage and timing variations between the outputs of the two magnetic switches caused by any of a variety of factors. The only remaining variation is a very small fixed timing offset caused by the geometry and length of the loop itself. 13 figs.
Chaos in the low-lying collective states of even-even nuclei: Classical limit
Alhassid, Y.; Whelan, N. (Center for Theoretical Physics, Sloane Physics Laboratory, Yale University, New Haven, CT (USA) A. W. Wright Nuclear Structure Laboratory, Yale University, New Haven, CT (USA))
1991-06-01
We study the classical dynamical behavior of a family of Hamiltonians in the interacting boson model which describe the low-lying collective states of even-even nuclei. Two measures of classical chaos, the fractional volume of chaotic trajectories and the average largest Lyapunov exponent, are studied as a function of energy, angular momentum, and a parameter which interpolates between rotational and {gamma}-unstable nuclei. Near these two limits the dynamics is regular but in the transition region it becomes chaotic. The results agree with a previous study of quantum chaos in the corresponding quantal model, where spectral and {ital E}(2) intensity fluctuations were analyzed. Contrary to most previous numerical studies which were restricted to unrealistic models in two degrees of freedom, the present model is realistic and has five degrees of freedom. The latter correspond to the five quadrupole nuclear shape degrees of freedom.
Generalized splines for Radon transform on compact Lie groups with applications to crystallography
Swanhild Bernstein; Svend Ebert; Isaac Z. Pesenson
2012-04-27
The Radon transform Rf of functions f on SO(3) has recently been applied extensively in texture analysis, i.e. the analysis of preferred crystallographic orientation. In practice one has to determine the orientation probability density function f \\in L2(SO(3)) from Rf \\in L2(S2\\times S2) which is known only on a discrete set of points. Since one has only partial information about Rf the inversion of the Radon transform becomes an ill-posed inverse problem. Motivated by this problem we define a new notion of the Radon transform Rf of functions f on general compact Lie groups and introduce two approximate inversion algorithms which utilize our previously developed generalized variational splines on manifolds. Our new algorithms fit very well to the application of Radon transform on SO(3) to texture analysis.
Animalu, A.O.E.
1987-11-01
A new approach to the ''extended relativity'' principle proposed by Recami, Mignani, and others, in which the speed of light (c) is invariant with respect to both subluminal (v
Magnetic field distribution in the plasma flow generated by a plasma focus discharge
Mitrofanov, K. N.; Krauz, V. I. Myalton, V. V.; Velikhov, E. P.; Vinogradov, V. P.; Vinogradova, Yu. V.
2014-11-15
The magnetic field in the plasma jet propagating from the plasma pinch region along the axis of the chamber in a megajoule PF-3 plasma focus facility is studied. The dynamics of plasma with a trapped magnetic flow is analyzed. The spatial sizes of the plasma jet region in which the magnetic field concentrates are determined in the radial and axial directions. The magnetic field configuration in the plasma jet is investigated: the radial distribution of the azimuthal component of the magnetic field inside the jet is determined. It is shown that the magnetic induction vector at a given point in space can change its direction during the plasma flight. Conclusions regarding the symmetry of the plasma flow propagation relative to the chamber axis are drawn.
Controlling Magnetism at the Nanoscale
Wong, Jared
2012-01-01
157 A.2 Magnetism Unit Conversion148 A.1 Magnetism Unit ConversionA·m) Table A.1: Magnetism Unit Conversion Table Quantity A.1
Transient horizontal magnetic fields in solar plage regions
R. Ishikawa; S. Tsuneta; K. Ichimoto; H. Isobe; Y. Katsukawa; B. W. Lites; S. Nagata; T. Shimizu; R. A. Shine; Y. Suematsu; T. D. Tarbell; A. M. Title
2008-02-13
We report the discovery of isolated, small-scale emerging magnetic fields in a plage region with the Solar Optical Telescope aboard Hinode. Spectro-polarimetric observations were carried out with a cadence of 34 seconds for the plage region located near disc center. The vector magnetic fields are inferred by Milne-Eddington inversion. The observations reveal widespread occurrence of transient, spatially isolated horizontal magnetic fields. The lateral extent of the horizontal magnetic fields is comparable to the size of photospheric granules. These horizontal magnetic fields seem to be tossed about by upflows and downflows of the granular convection. We also report an event that appears to be driven by the magnetic buoyancy instability. We refer to buoyancy-driven emergence as type1 and convection-driven emergence as type2. Although both events have magnetic field strengths of about 600 G, the filling factor of type1 is a factor of two larger than that of type2. Our finding suggests that the granular convection in the plage regions is characterized by a high rate of occurrence of granular-sized transient horizontal fields.
Quark deconfinement and gluon condensate in a weak magnetic field
Alejandro Ayala; C. A. Dominguez; L. A. Hernandez; M. Loewe; Juan Cristobal Rojas; Cristian Villavicencio
2015-07-01
We study QCD finite energy sum rules (FESR) for the axial-vector current correlator in the presence of a magnetic field, in the weak field limit and at zero temperature. We find that the perturbative QCD as well as the hadronic contribution to the sum rules get explicit magnetic field-dependent corrections and that these in turn induce a magnetic field dependence on the deconfinement phenomenological parameter s_0 and on the gluon condensate. The leading corrections turn out to be quadratic in the field strength. We find from the dimension d=2 first FESR that the magnetic field dependence of s_0 is proportional to the absolute value of the light-quark condensate. Hence, it increases with increasing field strength. This implies that the parameters describing chiral symmetry restoration and deconfinement behave similarly as functions of the magnetic filed. Thus, at zero temperature the magnetic field is a catalysing agent of both chiral symmetry breaking and confinement. From the dimension d=4 second FESR we obtain the behavior of the gluon condensate in the presence of the external magnetic field. This condensate also increases with increasing field strength.
Automatic Parallelization of Classification Systems based on Support Vector Machines: Comparison and Application to JET Database
Formation of Moving Magnetic Features and Penumbral Magnetic Fields with Hinode/SOT
Masahito Kubo; Kiyoshi Ichimoto; Toshifumi Shimizu; Saku Tsuneta; Yoshinori Suematsu; Yukio Katsukawa; Shin'ichi Nagata; Theodore D Tarbell; Richard A Shine; Alan M Title; Zoe A Frank; Bruce W Lites; David Elmore
2007-09-12
Vector magnetic fields of moving magnetic features (MMFs) are well observed with the Solar Optical Telescope (SOT) aboard the Hinode satellite. We focus on the evolution of three MMFs with the SOT in this study. We found that an MMF having relatively vertical fields with polarity same as the sunspot is detached from the penumbra around the granules appeared in the outer penumbra. This suggests that granular motions in the outer penumbra are responsible for the disintegration of the sunspot. Two MMFs with polarity opposite to the sunspot are located around the outer edge of horizontal fields extending from the penumbra. This is an evidence that the MMFs with polarity opposite to the sunspot are prolongation of penumbral horizontal fields. Radshifts larger than sonic velocity in the photosphere are detected for some of the MMFs with polarity opposite to the sunspot.
Roles of High-lying Excited States on Neutrino Reactions and the Gamow Teller strength for $^{40}$Ar
Eunja Ha; Myung-Ki Cheoun
2011-08-22
Neutrino reactions on $^{40}$Ar via charged and neutral currents for detecting solar and core collapsing supernovae (SNe) neutrinos and the Gamow Teller strength are calculated by considering the high-lying excited states up to a few tens of MeV region. The nucleus was originally exploited to identify the solar neutrino emitted from $^{8}$B produced in the pp-chains on the Sun. With the higher energy neutrinos emitted from the core collapsing SNe, contributions from higher multi-pole transitions including the spin dipole resonances (SDR) as well as the Gamow Teller (GT) and Fermi transitions are shown to be important ingredients for understanding reactions induced by the SNe as well as solar neutrinos. In this work, we focused on the role of high-lying excited states which are located beyond a few low-lying states known in the experiment. Expected large difference between the cross sections of $\
Vector Higgs-portal dark matter and the invisible Higgs
Oleg Lebedev; Hyun Min Lee; Yann Mambrini
2012-01-10
The Higgs sector of the Standard Model offers a unique probe of the hidden sector. In this work, we explore the possibility of renormalizable Higgs couplings to the hidden sector vector fields which can constitute dark matter (DM). Abelian gauge sectors with minimal field content, necessary to render the gauge fields massive, have a natural Z_2 parity. This symmetry ensures stability of the vector fields making them viable dark matter candidates, while evading the usual electroweak constraints. We illustrate this idea with the Stueckelberg and Higgs mechanisms. Vector DM is consistent with the WMAP, XENON100, and LHC constraints, while it can affect significantly the invisible Higgs decay. Due to the enhanced branching ratio for the Higgs decay into the longitudinal components of the vector field, the vector Higgs portal provides an efficient way to hide the Higgs at the LHC. This could be the reason why the latest combined ATLAS/CMS data did not bring evidence for the existence of the Higgs boson.
Magnetic Graphene Nanohole Superlattices
Yu, Decai; Liu, Miao; Liu, Wei; Liu, Feng
2008-01-01
We investigate the magnetic properties of nano-holes (NHs) patterned in graphene using first principles calculations. We show that superlattices consisting of a periodic array of NHs form a new family of 2D crystalline "bulk" magnets whose collective magnetic behavior is governed by inter-NH spin-spin interaction. They exhibit long-range magnetic order well above room temperature. Furthermore, magnetic semiconductors can be made by doping magnetic NHs into semiconducting NH superlattices. Our findings offer a new material system for fundamental studies of spin-spin interaction and magnetic ordering in low dimensions, and open up the exciting opportunities of making engineered magnetic materials for storage media and spintronics applications.
Magnetic assisted statistical assembly
Cheng, Diana I
2008-01-01
The objective of this thesis is to develop a process using magnetic forces to assemble micro-components into recesses on silicon based integrated circuits. Patterned SmCo magnetic thin films at the bottom of recesses are ...
Yao, Jinping; Jia, Xinyan; Hao, Xiaolei; Zeng, Bin; Jing, Chenrui; Chu, Wei; Ni, Jielei; Zhang, Haisu; Xie, Hongqiang; Zhang, Chaojin; Zhao, Zengxiu; Chen, Jing; Liu, Xiaojun; Cheng, Ya; Xu, Zhizhan
2013-01-01
We show that fluorescence emission induced by strong field tunnel ionization of carbon dioxide from its lower-lying orbitals exhibits a peculiar molecular alignment dependence. The experimentally measured alignment-dependence of the fluorescence agrees with the alignment-dependence of the ionization probability calculated in the framework of the strong field approximation. Our results demonstrate the feasibility of an all-optical approach for shedding more light on the ionization mechanisms of molecules from their lower-lying orbitals in tunnel ionization regime.
A comparison of eddy current effects in a single sided magnetic thrust bearing
DeWeese, Randall Thomas
1996-01-01
of nodal vector potential Surface Area (m ) Magnetic flux density (tesla) Force based on virtual work (N) Vertical force yielded from the macro FOR2DS One dimensional calculated vertical force on rotor H I(A, ) L N Ni Ns Rs Magnetic field... if the flux density remains below one tesla for silicon iron materials (Magnetic, 1995). All the flux densities used remained below one tesla, so the reluctance of the back iron and rotor were neglected. From Eq. (3. 7) we arrive at Eq. (3. 8). 2@R, =NI...
Rotating superconductor magnet for producing rotating lobed magnetic field lines
Hilal, Sadek K. (Englewood Cliffs, NJ); Sampson, William B. (Bellport, NY); Leonard, Edward F. (Leonia, NJ)
1978-01-01
This invention provides a rotating superconductor magnet for producing a rotating lobed magnetic field, comprising a cryostat; a superconducting magnet in the cryostat having a collar for producing a lobed magnetic field having oppositely directed adjacent field lines; rotatable support means for selectively rotating the superconductor magnet; and means for energizing the superconductor magnet.
Magnetic Fields Analogous to electric field, a magnet
Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University
Magnetic Fields Analogous to electric field, a magnet produces a magnetic field, B Set up a B field two ways: Moving electrically charged particles Current in a wire Intrinsic magnetic field Basic) Opposite magnetic poles attract like magnetic poles repel #12;Like the electric field lines
Vecchio, Frank J.
Notes on Use of VecTor Programs: The VecTor analysis programs operate in a DOS-environment. Various input files are created or edited using standard text editors; output files are similarly viewed using Works, and output results can be viewed using the post-processor Augustus. Each VecTor program requires
NEAR-IR IMAGING POLARIMETRY TOWARD A BRIGHT-RIMMED CLOUD: MAGNETIC FIELD IN SFO 74
Kusune, Takayoshi; Sugitani, Koji [Graduate School of Natural Sciences, Nagoya City University, Mizuho-ku, Nagoya 467-8501 (Japan); Miao, Jingqi [Centre for Astrophysics and Planetary Science, School of Physical Sciences, University of Kent, Canterbury, Kent CT2 7NR (United Kingdom); Tamura, Motohide; Kwon, Jungmi [Department of Astronomy, University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033 (Japan); Sato, Yaeko [National Astronomical Observatory, 2-21-1 Osawa, Mikata, Tokyo 181-8588 (Japan); Watanabe, Makoto [Department of Cosmosciences, Hokkaido University, Kita 10, Nishi 8, Kita-ku, Sapporo, Hokkaido 060-0810 (Japan); Nishiyama, Shogo [Faculty of Education, Miyagi University of Education, Sendai 980-0845 (Japan); Nagayama, Takahiro [Department of Physics, Kagoshima University, 1-21-35 Korimoto, Kagoshima 890-0065 (Japan); Sato, Shuji [Department of Astrophysics, Nagoya University, Chikusa-ku, Nagoya 464-8602 (Japan)
2015-01-01
We have made near-infrared (JHK {sub s}) imaging polarimetry of a bright-rimmed cloud (SFO 74). The polarization vector maps clearly show that the magnetic field in the layer just behind the bright rim is running along the rim, quite different from its ambient magnetic field. The direction of the magnetic field just behind the tip rim is almost perpendicular to that of the incident UV radiation, and the magnetic field configuration appears to be symmetric as a whole with respect to the cloud symmetry axis. We estimated the column and number densities in the two regions (just inside and far inside the tip rim) and then derived the magnetic field strength, applying the Chandrasekhar-Fermi method. The estimated magnetic field strength just inside the tip rim, ?90 ?G, is stronger than that far inside, ?30 ?G. This suggests that the magnetic field strength just inside the tip rim is enhanced by the UV-radiation-induced shock. The shock increases the density within the top layer around the tip and thus increases the strength of the magnetic field. The magnetic pressure seems to be comparable to the turbulent one just inside the tip rim, implying a significant contribution of the magnetic field to the total internal pressure. The mass-to-flux ratio was estimated to be close to the critical value just inside the tip rim. We speculate that the flat-topped bright rim of SFO 74 could be formed by the magnetic field effect.
Magnetic nanohole superlattices
Liu, Feng
2013-05-14
A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.
Metallic Magnetic Hetrostructures
Leung, Chi Wah
.2.2 Domains and magnetization processes 1.2.2.1 Domains and domain walls 1.2.2.2 Magnetization reversal and hysteresis 1.2.2.3 Modelling of magnetization process 1.3 Sputter deposition of thin films in this project 1.3.1 Substrate preparation 1.3.2 ‘UFO...
Remote sensing, global warming, and vector-borne disease
Wood, B.; Beck, L.; Dister, S.; Lobitz, B.
1997-12-31
The relationship between climate change and the pattern of vector-borne disease can be viewed at a variety of spatial and temporal scales. At one extreme are changes such as global warming, which are continental in scale and occur over periods of years, decades, or longer. At the opposite extreme are changes associated with severe weather events, which can occur at local and regional scales over periods of days, weeks, or months. Key ecological factors affecting the distribution of vector-borne diseases include temperature, precipitation, and habitat availability, and their impact on vectors, pathogens, reservoirs, and hosts. Global warming can potentially alter these factors, thereby affecting the spatial and temporal patterns of disease.
Scalars, Vectors and Tensors from Metric-Affine Gravity
Karahan, Canan N; Demir, Durmus A
2011-01-01
The metric-affine gravity provides a useful framework for analyzing gravitational dynamics since it treats metric tensor and affine connection as fundamentally independent variables. In this work, we show that, a metric-affine gravity theory composed of the invariants formed from non-metricity, torsion and curvature tensors decomposes exhaustively into a theory of scalar, vector and tensor fields. These fields are natural candidates for the ones needed by various cosmological phenomena. Indeed, we show that the model accommodates TeVeS gravity (relativistic modified gravity theory), vector inflation, and aether-like models. Detailed analyses of these and other phenomena can lead to a standard metric-affine gravity model encoding scalars, vectors and tensors necessitated by cosmology.
Scalars, Vectors and Tensors from Metric-Affine Gravity
Canan N. Karahan; Asli Altas; Durmus A. Demir
2013-02-02
The metric-affine gravity provides a useful framework for analyzing gravitational dynamics since it treats metric tensor and affine connection as fundamentally independent variables. In this work, we show that, a metric-affine gravity theory composed of the invariants formed from non-metricity, torsion and curvature tensors can be decomposed into a theory of scalar, vector and tensor fields. These fields are natural candidates for the ones needed by various cosmological and other phenomena. Indeed, we show that the model accommodates TeVeS gravity (relativistic modified gravity theory), vector inflation, and aether-like models. Detailed analyses of these and other phenomena can lead to a standard metric-affine gravity model encoding scalars, vectors and tensors.
Computing nonlinear force free coronal magnetic fields
T. Wiegelmann; T. Neukirch
2008-01-21
Knowledge of the structure of the coronal magnetic field is important for our understanding of many solar activity phenomena, e.g. flares and CMEs. However, the direct measurement of coronal magnetic fields is not possible with present methods, and therefore the coronal field has to be extrapolated from photospheric measurements. Due to the low plasma beta the coronal magnetic field can usually be assumed to be approximately force free, with electric currents flowing along the magnetic field lines. There are both observational and theoretical reasons which suggest that at least prior to an eruption the coronal magnetic field is in a nonlinear force free state. Unfortunately the computation of nonlinear force free fields is way more difficult than potential or linear force free fields and analytic solutions are not generally available. We discuss several methods which have been proposed to compute nonlinear force free fields and focus particularly on an optimization method which has been suggested recently. We compare the numerical performance of a newly developed numerical code based on the optimization method with the performance of another code based on an MHD relaxation method if both codes are applied to the reconstruction of a semi-analytic nonlinear force-free solution. The optimization method has also been tested for cases where we add random noise to the perfect boundary conditions of the analytic solution, in this way mimicking the more realistic case where the boundary conditions are given by vector magnetogram data. We find that the convergence properties of the optimization method are affected by adding noise to the boundary data and we discuss possibilities to overcome this difficulty.
Implicit Methods for the Magnetohydrodynamic Description of Magnetically Confined Plasmas
S.C. Jardin
2010-09-28
Implicit algorithms are essential for predicting the slow growth and saturation of global instabilities in today’s magnetically confined fusion plasma experiments. Present day algorithms for obtaining implicit solutions to the magnetohydrodynamic (MHD) equations for highly magnetized plasma have their roots in algorithms used in the 1960s and 1970s. However, today’s computers and modern linear and non?linear solver techniques make practical much more comprehensive implicit algorithms than were previously possible. Combining these advanced implicit algorithms with highly accurate spatial representations of the vector fields describing the plasma flow and magnetic fields and with improved methods of calculating anisotropic thermal conduction now makes possible simulations of fusion experiments using realistic values of plasma parameters and actual configuration geometry.
Vector Dark Matter through a Radiative Higgs Portal
Anthony DiFranzo; Patrick J. Fox; Tim M. P. Tait
2015-12-21
We study a model of spin-1 dark matter which interacts with the Standard Model predominantly via exchange of Higgs bosons. We propose an alternative UV completion to the usual Vector Dark Matter Higgs Portal, in which vector-like fermions charged under SU(2)$_W \\times$ U(1)$_Y$ and under the dark gauge group, U(1)$^\\prime$, generate an effective interaction between the Higgs and the dark matter at one loop. We explore the resulting phenomenology and show that this dark matter candidate is a viable thermal relic and satisfies Higgs invisible width constraints as well as direct detection bounds.
Quantum dynamics of relativistic bosons through nonminimal vector square potentials
de Oliveira, Luiz P
2016-01-01
The dynamics of relativistic scalar bosons through nonminimal vector square (well and barrier) potentials is studied in the Duffin-Kemmer-Petiau (DKP) formalism. We show that the problem can be mapped in effective Schrodinger equations for a component of the DKP spinor. An oscillatory transmission coefficient is found and there is total reflection. Additionally, the energy spectrum of bound states is obtained and reveals the Schiff-Snyder-Weinberg effect, for specific conditions the potential lodges bound states of particles and antiparticles. Comments about the vector bosons problem subject to square potentials are present.
Quantum support vector machine for big data classification
Patrick Rebentrost; Masoud Mohseni; Seth Lloyd
2014-07-10
Supervised machine learning is the classification of new data based on already classified training examples. In this work, we show that the support vector machine, an optimized binary classifier, can be implemented on a quantum computer, with complexity logarithmic in the size of the vectors and the number of training examples. In cases when classical sampling algorithms require polynomial time, an exponential speed-up is obtained. At the core of this quantum big data algorithm is a non-sparse matrix exponentiation technique for efficiently performing a matrix inversion of the training data inner-product (kernel) matrix.
DEVELOPMENT AND TESTING OF HIGH POWER RF VECTOR MODULATORS*
Kang, Yoon W [ORNL; Wilson, Joshua L [ORNL; Champion, Mark [FNAL; Hardek, Thomas W [ORNL; Kim, Sang-Ho [ORNL; McCarthy, Mike [ORNL; Vassioutchenko, Alexandre V [ORNL
2007-01-01
A fan-out RF power distribution system can allow many accelerating cavities to be powered by a single high-power klystron amplifier. High-power vector modulators can perform independent control of amplitudes and phases of RF voltages at the cavities without changing the klystron signal. A prototype highpower RF vector modulator employing a quadrature hybrid and two ferrite phase shifters in coaxial TEM transmission lines has been built and tested for 402.5 MHz. RF properties of the design and results of high power testing are presented.
Magnetically attached sputter targets
Makowiecki, D.M.; McKernan, M.A.
1994-02-15
An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.
Explicit Baker-Campbell-Hausdorff formulae for some specific Lie algebras
Van-Brunt, Alexander
2015-01-01
In a previous article, [arXiv:1501.02506, JPhysA {\\bf48} (2015) 225207], we demonstrated that whenever $[X,Y] = u X + vY + cI$ the Baker-Campbell-Hausdorff formula reduces to the tractable closed-form expression \\[ Z(X,Y)=\\ln( e^X e^Y ) = X+Y+ f(u,v) \\; [X,Y], \\] where $f(u,v)=f(v,u)$ is explicitly given by \\[ f(u,v) = {(u-v)e^{u+v}-(ue^u-ve^v)\\over u v (e^u - e^v)} = {(u-v)-(ue^{-v}-ve^{-u})\\over u v (e^{-v} - e^{-u})}. \\] This is much more general than the results usually presented for either the Heisenberg commutator $[P,Q]=-i\\hbar I$, or the creation-destruction commutator $[a,a^\\dagger]=I$. In the current article we shall further generalize and extend this result, primarily by relaxing the input assumptions. We shall work with the structure constants $f_{ab}{}^c$ of the Lie algebra, (defined by $[T_a,T_b] = f_{ab}{}^c \\; T_c$), and identify suitable constraints one can place on the structure constants to make the Baker--Campbell--Hausdorff formula tractable. We shall also develop related results using th...
The chiral magnetic nanomotors
Morozov, Konstantin I
2013-01-01
Propulsion of the chiral magnetic nanomotors powered by a rotating magnetic field is in the focus of the modern biomedical applications. This technology relies on strong interaction of dynamic and magnetic degrees of freedom of the system. Here we study in detail various experimentally observed regimes of the helical nanomotor orientation and propulsion depending on the actuation frequency, and establish the relation of these two properties with remanent magnetization and geometry of the helical nanomotors. The theoretical predictions for the transition between the regimes and nanomotor orientation and propulsion speed are in excellent agreement with available experimental data. The proposed theory offers a few simple guidelines towards the optimal design of the magnetic nanomotors. In particular, efficient nanomotors should be fabricated of hard magnetics, e.g., cobalt, magnetized transversally and have the geometry of a normal helix with a helical angle of 35-45 degrees.
Scheibert, Julien
Analytical model of surface uplift above axisymmetric flat-lying magma intrusions: Implications model of surface uplift upon sills and laccoliths, based on the formulation of a thin bending plate formulation, our model accounts for (i) axi-symmetrical uplift, (ii) both upon and outside the intrusion
Harman, Neal.A.
1 Research Ethics, some general principles 1. The primary responsibility for the ethical conduct of research lies with the researcher. The researcher should consider their project design against standard ethical guidelines for the conduct of research (see below for links to relevant documents), in particular
A finite subgroup of the exceptional Lie group G 2 R C Kingyx F Toumazetz--and B. G. Wybourne#%
Toumazet, Frédéric
of the rotation group in seven dimensions, SO(7), and furthermore, that the physical rotation group SO(3A finite subgroup of the exceptional Lie group G 2 R C Kingyx F Toumazetz-- and B. G. Wybourne#% y Abstract. With a view to further refining the use of the exceptional group G 2 in atomic and nuclear
Chapman, Robin
's eight term exact sequence in integral group homology [BrLo] to an eight term exact sequence in group of nonabelian derived functors, an eight term exact sequence of Lie algebra homology with /q coefficients homology with Zq = Z/qZ coefficients, where q is a nonnegative integer. For any group G and its normal
Continetti, Robert E.
Study of the low-lying electronic states of CCO by photoelectron spectroscopy of CCO and ab initio , studies of the energetics and dynamics of these molecules are of continued interest. Pho- toelectron spectroscopy of negative ions provides a powerful method for studying the structure and energetics of both
May, J. Peter
1965-01-01
. Math. Soc. 71(1965), 372377. [2] The cohomology of the Steenrod algebra; stable homotopy groups of spheres. Bull. Amer. Math. Soc. 71(1965), 377380. [3] The cohomology of restricted Lie algebras Massey products for DGA-algebras. Trans. Amer. Math. Soc. 122(1966), 334340. [5] Simplicial objects
California at Santa Cruz, University of
are the traceless hermitian generators of the Lie algebra su(3), analogous to the Pauli matrices of su(2). The eight
California at Santa Cruz, University of
are the traceless hermitian generators of the Lie algebra su(3), analogous to the Pauli matrices of su(2). The eight
Near-Sun Speed of CMEs and the Magnetic Non-potentiality of their Source Active Regions
Tiwari, Sanjiv K; Moore, Ronald L; Venkatakrishnan, P; Winebarger, Amy R; Khazanov, Igor G
2015-01-01
We show that the speed of the fastest coronal mass ejections (CMEs) that an active region (AR) can produce can be predicted from a vector magnetogram of the AR. This is shown by logarithmic plots of CME speed (from the SOHO LASCO CME catalog) versus each of ten AR-integrated magnetic parameters (AR magnetic flux, three different AR magnetic-twist parameters, and six AR free-magnetic-energy proxies) measured from the vertical and horizontal field components of vector magnetograms (from the {\\it Solar Dynamics Observatory's Helioseismic and Magnetic Imager}) of the source ARs of 189 CMEs. These plots show: (1) the speed of the fastest CMEs that an AR can produce increases with each of these whole-AR magnetic parameters, and (2) that one of the AR magnetic-twist parameters and the corresponding free-magnetic-energy proxy each determine the CME-speed upper-limit line somewhat better than any of the other eight whole-AR magnetic parameters.
Rekveldt, M. Theo; Dijk, Niels H. van; Grigoriev, Serguei V.; Kraan, Wicher H.; Bouwman, Wim G. [Department of Radiation, Radionuclides and Reactors, Faculty of Applied Sciences, Delft University of Technology, 2629 JB Delft (Netherlands); Petersburg Nuclear Physics Institute, 188300 Gatchina, St-Petersburg District (Russian Federation); Department of Radiation, Radionuclides and Reactors, Faculty of Applied Sciences, Delft University of Technology, 2629 JB Delft (Netherlands)
2006-07-15
The recently developed magnetic spin-echo small-angle neutron scattering (SANS) technique provides unique information about the distance correlation of the local vector magnetization as a function of the spin-echo length within a magnetic material. The technique probes the magnetic correlations on a length scale from 10 nm up to 10 {mu}m within the bulk of a magnetic material by evaluating the Larmor precession of a polarized neutron beam in a spin-echo setup. The characteristics of the spin-echo SANS technique are discussed and compared to those of the more conventional neutron depolarization technique. Both of these techniques probe the average size of the magnetic inhomogeneities and the local magnetic texture. The magnetic spin-echo SANS technique gives information on the size distribution of these magnetic inhomogeneities perpendicular to the beam and, in principle, independent on the local magnetic induction. This information is not accessible by the neutron depolarization technique that gives the average size parallel to the beam multiplied with the square of the local magnetic induction. The basic possibilities of the magnetic spin-echo SANS technique are demonstrated by experiments on samples with a strong magnetic texture.
Carroll, S.; Fowler, T.; Peters, E.; Power, W.; Reed, M.
1994-01-05
The Gas Research Institute (GRI) has been sponsoring the development of a vehicle and sensors for an integrated nondestructive internal inspection system for natural gas distribution pipes. Arthur D. Little has developed two sensor technologies, Vector Magnetometry (VM) and Lightwave Defect Imaging (LDI) for the system. The Vector Magnetometry sensor utilizes multiple arrays of miniature detection coils (fluxgate magnetometer elements); a three-axis array measures both the amplitude and phase of the magnetic leakage field that occurs in the vicinity of pipe wall defects. This technology is applicable to both cast iron and steel pipe.
Magnetic helicity and energy spectra of a solar active region
Zhang, Hongqi; Sokoloff, D D
2013-01-01
We compute magnetic helicity and energy spectra of the solar active region NOAA 11158 during 11-15 February 2011 at 20 degr southern heliographic latitude using observational photospheric vector magnetograms. We adopt the isotropic representation of the Fourier-transformed two-point correlation tensor of the magnetic field. The sign of magnetic helicity turns out to be predominantly positive at all wavenumbers. This sign is consistent with what is theoretically expected for the southern hemisphere. The relative magnetic helicity is around 8% and strongest at intermediate wavenumbers of k ~ 0.4 Mm^{-1}, corresponding to a scale of 2 pi/k ~ 16 Mm. The same sign and a somewhat smaller value is also found for the relative current helicity evaluated in real space based on the vertical components of magnetic field and current density. The current helicity spectrum is estimated from the magnetic helicity spectrum and its modulus shows a k^{-5/3} spectrum at large wavenumbers. A similar power law is also obtained for...
Adventures in Vectorizing the Community Land Model Forrest M. Hoffman
Hoffman, Forrest M.
Institute of Electric Power Industry (CRIEPI) James B. White III, Patrick Worley, and John Drake Oak Ridge) on the IBM Power4, the Earth Simulator, and the Cray X1 are compared. #12;1 Introduction The Community Land-based scalar multi-processor computer platforms and re- sulted in code which would not vectorize. The avail
On the Context-Freeness Problem for Vector Addition Systems
, or equivalently vector addition systems (VAS), are widely recognized as a central model for concurrent systems one of the most studied formalisms for the modeling and analysis of concurrent systems. Despite their fairly large expressive power, many verification problems are decidable for VAS: boundedness
Vibration-based Terrain Classification Using Support Vector Machines
Zell, Andreas
Vibration-based Terrain Classification Using Support Vector Machines Christian Weiss, Holger Fr a method for terrain classification based on vibration induced in the vehicle's body. An accelerometer mounted on the vehicle measures the vibration perpendicular to the ground surface. We experimentally
Hybrid MPI/OpenMP parallel support vector machine training
2009-01-12
Jan 6, 2009 ... a mixture of multiple SVMs where single SVMs are trained on subsets of the training set and a neural network is used to assign samples to different ... port vector machines address this difficulty [Ferris and Munson, 2003, Fine ... though previous investigations have revealed mixed results [Smith and Bull,.
Environmental and Pollution Spatial Data Classification with Support Vector Machines
Gilardi, Nicolas
Environmental and Pollution Spatial Data Classification with Support Vector Machines and pollution spatial data analysis and modeling. The main attention is paid to classification of spatially be chosen by minimizing testing error. Real data on sediments pollution in the Geneva lake are used. 1
Soft Vector Processors with Streaming Pipelines A. Severance , J. Edwards
Lemieux, Guy
Soft Vector Processors with Streaming Pipelines A. Severance , J. Edwards aaronsev-multiplexed fashion, this does not exploit a key strength of FPGA performance: pipeline par- allelism. This paper shows how streaming pipelines can be integrated into the datapath of a SVP to achieve dramatic speedups
Evaluation of a Vector Hypercube for Seismic Modelling Seismic modelling
Renaut, Rosemary
Evaluation of a Vector Hypercube for Seismic Modelling Abstract Seismic modelling is a computationally to produce realistic seismic traces intensive problem. A 2D syn- Rosemary Renautt and Johnny equation is the first step in the generation of a synthetic seismogram as an aid in the interpretation
ORIGINAL ARTICLE Why is HIV not vector-borne?
Day, Troy
virus, Dengue, and other viral hemorrhagic fevers. Although several of these pathogens are transmitted be vector-borne (e.g., transmit- ted via mosquitoes) but it has since become widely accepted, mosquito. Correspondence Troy Day, Department of Mathematics and Statistics, Jeffery Hall, Queen
December 2001 Trevor Hastie, Stanford Statistics 1 Support Vector Machines,
Hastie, Trevor
December 2001 Trevor Hastie, Stanford Statistics 1 Support Vector Machines, Kernel Logistic in Optimization and Computational Algorithms (NTOC2001) December 9-13, 2001, Kyodai-Kaikan, Kyoto, Japan http://www-stat.stanford.edu/hastie/Papers/ivmtalk.pdf #12;December 2001 Trevor Hastie, Stanford Statistics 2 Outline Â· Optimal separating hyperplanes
Probabilistic forecasting of solar flares from vector magnetogram data
Barnes, Graham
Probabilistic forecasting of solar flares from vector magnetogram data G. Barnes,1 K. D. Leka,1 E to solar flare forecasting, adapted to provide the probability that a measurement belongs to either group, the groups in this case being solar active regions which produced a flare within 24 hours and those
Support Vector Machine Classification of Microarray Gene Expression Data
Noble, William Stafford
using expression data. In addition, SVM performance is compared to four standard machine learningSupport Vector Machine Classification of Microarray Gene Expression Data UCSC-CRL-99-09 Michael P 95065 mpbrown,bgrundy,dave,haussler @cse.ucsc.edu ß Center for Molecular Biology of RNA Department
Role of the nuclear vector potential in deep inelastic scattering
W. Detmold; G. A. Miller; J. R. Smith
2005-09-15
We study the influence of the strong nuclear vector potential, treated using the mean-field approximation, in deep inelastic scattering. A consistent treatment of the electromagnetic current operator, combined with the use of the operator product expansion is presented and discussed.
Photoproduction of Heavy Vector Mesons at the LHC
Joakim Nystrand
2005-03-23
The strong electromagnetic fields associated with high energy protons and nuclei may lead to exclusive photoproduction of vector mesons in proton-proton and nucleus-nucleus collisions at the LHC. This paper will discuss the expected cross sections and rapidity and transverse momentum distributions.
World Malaria Day at UC Davis: Research in vector
Ishida, Yuko
World Malaria Day at UC Davis: Research in vector biology and genetics at UC Davis 25 April 2012 Davis, Davis, CA Purpose: In recognition of World Malaria Day and in support of the Roll Back Malaria:54-4:00pm Concluding Remarks Schedule World Malaria
Improving Word Sense Discrimination with Gloss Augmented Feature Vectors
Pedersen, Ted
Improving Word Sense Discrimination with Gloss Augmented Feature Vectors Amruta Purandare1 and Ted USA http://senseclusters.sourceforge.net Abstract. This paper presents a method of unsupervised word with information from the glosses found in a ma- chine readable dictionary. Each content word that occurs
ON LOCAL GEOMETRY OF VECTOR DISTRIBUTIONS WITH GIVEN JACOBI SYMBOLS
Zelenko, Igor
ON LOCAL GEOMETRY OF VECTOR DISTRIBUTIONS WITH GIVEN JACOBI SYMBOLS BORIS DOUBROV AND IGOR ZELENKO generating distribution, the Jacobi symbol. In contrast to the classical Tanaka symbol, the set of Jacobi Jacobi symbol. We describe all Jacobi symbols for which this procedure ends up in a finite number
Covariant Lyapunov Vectors for Rigid Disk Systems Hadrien Bosetti
Posch, Harald A.
Covariant Lyapunov Vectors for Rigid Disk Systems Hadrien Bosetti and Harald A. Posch Computational: October 17, 2010) We carry out extensive computer simulations to study the Lyapunov instability of a two enough to allow the formation of Lyapunov modes parallel to the x-axis of the box. The Oseledec splitting
Supersymmetric Higgs Production in Vector-Boson Fusion
Michael Rauch; Wolfgang Hollik; Tilman Plehn; Heidi Rzehak
2010-04-14
We present a full calculation of the supersymmetric NLO corrections to Higgs boson production via vector-boson fusion. The supersymmetric QCD corrections turn out to be significantly smaller than the electroweak ones. These higher-order corrections are an important ingredient to a precision analysis of the Higgs sector at the LHC.
A Hierarchical and Parallel Method for Training Support Vector Machines
Lu, Bao-Liang
handled by many modules. After training, all the trained modules are integrated into a modular system [4A Hierarchical and Parallel Method for Training Support Vector Machines Yimin Wen1,2 and Baoliang sequential methods need long training time, and some of parallel methods lead to generalization accuracy
Vector boson + multi jets at NLO Harald Ita, UCLA
California at Santa Cruz, University of
Vector boson + multi jets at NLO Harald Ita, UCLA In collaboration with C.F. Berger, Z. Bern, L · We · Z · W/Zqq, (missed jet) M L Mangano #12;Ws versus Zs ( leptons) W-boson · Larger cross section level hard scattering · parton model · perturbative QCD · jet algorithms Proton Proton PT(hard) Outgoing
Liu, Y.; Hoeksema, J. T.; Sun, X.
2014-03-01
Magnetic twist in solar active regions (ARs) has been found to have a hemispheric preference in sign (hemisphere rule): negative in the northern hemisphere and positive in the southern. The preference reported in previous studies ranges greatly, from ? 58% to 82%. In this study, we examine this hemispheric preference using vector magnetic field data taken by Helioseismic and Magnetic Imager and find that 75% ± 7% of 151 ARs studied obey the hemisphere rule, well within the preference range in previous studies. If the sample is divided into two groups—ARs having magnetic twist and writhe of the same sign and having opposite signs—the strength of the hemispheric preference differs substantially: 64% ± 11% for the former group and 87% ± 8% for the latter. This difference becomes even more significant in a sub-sample of 82 ARs having a simple bipole magnetic configuration: 56% ± 16% for the ARs having the same signs of twist and writhe, and 93% with lower and upper confidence bounds of 80% and 98% for the ARs having the opposite signs. The error reported here is a 95% confidence interval. This may suggest that, prior to emergence of magnetic tubes, either the sign of twist does not have a hemispheric preference or the twist is relatively weak.
Relation between photospheric flow fields and the magnetic field distribution on the solar surface
Simon, G.W.; Title, A.M.; Topka, K.P.; Tarbell, T.D.; Shine, R.A.
1988-04-01
Using the technique of local correlation tracking on a 28 minute time sequence of white-light images of solar granulation, the horizontal flow field on the solar surface is measured. The time series was obtained by the Solar Optical Universal Polarimeter (SOUP) on Spacelab 2 (Space Shuttle flight 51-F) and is free from atmospheric blurring and distortion. The SOUP flow fields have been compared with carefully aligned magnetograms taken over a nine hour period at the Big Bear Solar Observatory before, during, and after the SOUP images. The flow field and the magnetic field agree in considerable detail: vectors which define the flow of the white-light intensity pattern (granulation) point toward magnetic field regions, magnetic fields surround flow cells, and magnetic features move along the flow arrows. The projected locations of free particles (corks) in the measured flow field congregate at the same locations where the magnetic field is observed. 31 references.
Magnetic-Field-Induced Insulator-Conductor Transition in SU(2) Quenched Lattice Gauge Theory
Buividovich, P.V.; Kharzeev, D.; Chernodub, M.N., Kalaydzhyan, T., Luschevskaya, E.V., and M.I. Polikarpov
2010-09-24
We study the correlator of two vector currents in quenched SU(2) lattice gauge theory with a chirally invariant lattice Dirac operator with a constant external magnetic field. It is found that in the confinement phase the correlator of the components of the current parallel to the magnetic field decays much slower than in the absence of a magnetic field, while for other components the correlation length slightly decreases. We apply the maximal entropy method to extract the corresponding spectral function. In the limit of zero frequency this spectral function yields the electric conductivity of quenched theory. We find that in the confinement phase the external magnetic field induces nonzero electric conductivity along the direction of the field, transforming the system from an insulator into an anisotropic conductor. In the deconfinement phase the conductivity does not exhibit any sizable dependence on the magnetic field.
Ha, Taekjip
A-7 3An electron of charge | | and mass moves in the presence of a uniform magnetic field pointing in the z-direction . The motion of the electron is confined to the - plane. (a) As a warm up, write down by [ ] where is the canonical momentum, and is the magnetic vector potential. (c) The Hamiltonian
Nuclear magnetic relaxation of a three spin asymmetric molecule in a liquid
Kattawar, George Williford
1961-01-01
is the quaternion ~ ( o(/~) + g ~ Q &/2) &Z) The quantity C is a unit vector in the direction of the axis of the rotation, having components 19 C, =~a'C d', C, = ~s ~~ ~ &~=~+. A quaternion can be considered to be the sum of a scalar and a vector, (a + bC... for the degree of MASTER OF SCIENCE August 1961 Major Sub)ect: Physics NUCLEAR MAGNETIC RELAXATION OF A THREE SPIN ASYMMETRIC MOLECULE IN A LIQUID A Thesis By George W. Kattawar Approved as to style and content by: ), , i, ? a rman o Comm ttee g-C e...
Sheath formation criterion in magnetized electronegative plasmas with thermal ions
Hatami, M. M. [Physics Department of K N Toosi University of Technology, 15418-49611 Tehran (Iran, Islamic Republic of); Shokri, B. [Physics Department and Laser-Plasma Research Institute of Shahid Beheshti University, G. C., Evin, Tehran (Iran, Islamic Republic of)
2013-03-15
Taking into account the effect of collisions and positive ion temperatures, the sheath formation criterion is investigated in a weakly magnetized electronegative plasma consisting of electrons, negative and positive ions by using the hydrodynamics equations. It is assumed that the electron and negative ion density distributions are the Boltzmann distribution with two different temperatures. Also, it is assumed that the velocity of positive ions at the sheath edge is not normal to the wall (oblique entrance). Our results show that a sheath region will be formed when the initial velocity of positive ions or the ion Mach number M lies in a specific interval with particular upper and lower limits. Also, it is shown that the presence of the magnetic field affects both of these limits. Moreover, as an practical application, the density distribution of charged particles in the sheath region is studied for an allowable value of M, and it is seen that monotonically reduction of the positive ion density distribution leading to the sheath formation occurs only when M lies between two above mentioned limits.
Maximum Likelihood Estimation (MLE) of students' understanding of vector subtraction
Zollman, Dean
and Electricity and Magnetism have been collapsed together. In this short paper, we use an easily-understood exam (Mechanics) or second quarter (Electricity and Magnetism) introductory calculus-based physics course homework assignment con- sisted of participating in a one-hour session in a physics education research lab
Passive magnetic bearing system
Post, Richard F.
2014-09-02
An axial stabilizer for the rotor of a magnetic bearing provides external control of stiffness through switching in external inductances. External control also allows the stabilizer to become a part of a passive/active magnetic bearing system that requires no external source of power and no position sensor. Stabilizers for displacements transverse to the axis of rotation are provided that require only a single cylindrical Halbach array in its operation, and thus are especially suited for use in high rotation speed applications, such as flywheel energy storage systems. The elimination of the need of an inner cylindrical array solves the difficult mechanical problem of supplying support against centrifugal forces for the magnets of that array. Compensation is provided for the temperature variation of the strength of the magnetic fields of the permanent magnets in the levitating magnet arrays.
Christiansen, D.W.; Brown, W.F.
1984-01-01
A welder is described for automated closure of fuel pins by a pulsed magnetic process in which the open end of a length of cladding is positioned within a complementary tube surrounded by a pulsed magnetic welder. Seals are provided at each end of the tube, which can be evacuated or can receive tag gas for direct introduction to the cladding interior. Loading of magnetic rings and end caps is accomplished automatically in conjunction with the welding steps carried out within the tube.
Marts, D.J.; Richardson, J.G.; Albano, R.K.; Morrison, J.L. Jr.
1995-11-28
This invention discloses a D.C. magnetic latching solenoid that retains a moving armature in a first or second position by means of a pair of magnets, thereby having a zero-power requirement after actuation. The first or second position is selected by reversing the polarity of the D.C. voltage which is enough to overcome the holding power of either magnet and transfer the armature to an opposite position. The coil is then de-energized. 2 figs.
Magnetic Braids Anthony Yeates
Dundee, University of
function Main result Conclusion Examples 1. Magnetic loops in the solar corona. NASA Solar Dynamics of the potential a Hi,j a x = 2 a xi At each neutral p Hi,j a . The magnet function and it co field topology. Magnetic helicity H = V AÂ·BdV, B = Ã?A is a well-known global ideal invariant in a closed
HYPERFINE STRUCTURE CONSTANTS OF ENERGETICALLY HIGH-LYING LEVELS OF ODD PARITY OF ATOMIC VANADIUM
Güzelçimen, F.; Yap?c?, B.; Demir, G.; Er, A.; Öztürk, I. K.; Ba?ar, Gö.; Kröger, S.; Tamanis, M.; Ferber, R.; Docenko, D.; Ba?ar, Gü. E-mail: sophie.kroeger@htw-berlin.de
2014-09-01
High-resolution Fourier transform spectra of a vanadium-argon plasma have been recorded in the wavelength range of 365-670 nm (15,000-27,400 cm{sup –1}). Optical bandpass filters were used in the experimental setup to enhance the sensitivity of the Fourier transform spectrometer. In total, 138 atomic vanadium spectral lines showing resolved or partially resolved hyperfine structure have been analyzed to determine the magnetic dipole hyperfine structure constants A of the involved energy levels. One of the investigated lines has not been previously classified. As a result, the magnetic dipole hyperfine structure constants A for 90 energy levels are presented: 35 of them belong to the configuration 3d {sup 3}4s4p and 55 to the configuration 3d {sup 4}4p. Of these 90 constants, 67 have been determined for the first time, with 23 corresponding to the configuration 3d {sup 3}4s4p and 44 to 3d {sup 4}4p.
Magnetic Mirrors at the Nanoscale : Theory M. P. J. L. Chang, D. Jia1 and H. Nazari2
Chang, Mark J. L.
of heat from one wire coil to the defect will be higher than the rate due to uniform blackbody radiation. In the case of tungsten, for our typical spiral geometry, the heating rate is enhanced by a factor of 15 as 106 , which is evidently not appropriate. Keywords: Magnetic Mirrors, Vector Potential, Radiative Heat
Magnetically leviated superconducting bearing
Weinberger, Bernard R. (Avon, CT); Lynds, Jr., Lahmer (Glastonbury, CT)
1993-01-01
A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.
Royet, J.
2010-01-01
76SFOOO98. MAGNET CABLE MANUFACTURING John Royet Lawrenceused in this cable manufacturing are made of superconductingapplied during manufacturing. 2.2 Twist The composite
Vladimir A. Miransky; Igor A. Shovkovy
2015-04-10
A range of quantum field theoretical phenomena driven by external magnetic fields and their applications in relativistic systems and quasirelativistic condensed matter ones, such as graphene and Dirac/Weyl semimetals, are reviewed. We start by introducing the underlying physics of the magnetic catalysis. The dimensional reduction of the low-energy dynamics of relativistic fermions in an external magnetic field is explained and its role in catalyzing spontaneous symmetry breaking is emphasized. The general theoretical consideration is supplemented by the analysis of the magnetic catalysis in quantum electrodynamics, chromodynamics and quasirelativistic models relevant for condensed matter physics. By generalizing the ideas of the magnetic catalysis to the case of nonzero density and temperature, we argue that other interesting phenomena take place. The chiral magnetic and chiral separation effects are perhaps the most interesting among them. In addition to the general discussion of the physics underlying chiral magnetic and separation effects, we also review their possible phenomenological implications in heavy-ion collisions and compact stars. We also discuss the application of the magnetic catalysis ideas for the description of the quantum Hall effect in monolayer and bilayer graphene, and conclude that the generalized magnetic catalysis, including both the magnetic catalysis condensates and the quantum Hall ferromagnetic ones, lies at the basis of this phenomenon. We also consider how an external magnetic field affects the underlying physics in a class of three-dimensional quasirelativistic condensed matter systems, Dirac semimetals. While at sufficiently low temperatures and zero density of charge carriers, such semimetals are expected to reveal the regime of the magnetic catalysis, the regime of Weyl semimetals with chiral asymmetry is realized at nonzero density...
HIV-1 intracellular immunization via HIV-1 derived vector delivered genetic mechanisms
Swan, Christina Heidi
2006-01-01
long-term engraftment of NOD/SCID mice by HIV vectors.long-term engraftment of NOD/SCID mice by HIV vectors.HIV-1 infection in NOD/SCID-hu thy/liv thymocytes …………… 38
Everett, Anthany Laurence
2009-05-15
The coat protein of satellite panicum mosaic virus (SPMV) was used to stabilize viral vector gene inserts in planta. A Potato virus X (PVX) vector carrying the SPMV capsid protein (CP) gene was successfully stabilized through three serial passages...
Introduction to vectors and tensors, Vol 1: linear and multilinear algebra
Bowen, Ray M.; Wang, C. C.
1976-01-01
This work represents our effort to present the basic concepts of vector and tensor analysis. Volume I begins with a brief discussion of algebraic structures followed by a rather detailed discussion of the algebra of vectors ...
Asymmetric evolution of magnetic reconnection in collisionless accretion disk
Shirakawa, Keisuke Hoshino, Masahiro
2014-05-15
An evolution of a magnetic reconnection in a collisionless accretion disk is investigated using a 2.5 dimensional hybrid code simulation. In astrophysical disks, magnetorotational instability (MRI) is considered to play an important role by generating turbulence in the disk and contributes to an effective angular momentum transport through a turbulent viscosity. Magnetic reconnection, on the other hand, also plays an important role on the evolution of the disk through a dissipation of a magnetic field enhanced by a dynamo effect of MRI. In this study, we developed a hybrid code to calculate an evolution of a differentially rotating system. With this code, we first confirmed a linear growth of MRI. We also investigated a behavior of a particular structure of a current sheet, which would exist in the turbulence in the disk. From the calculation of the magnetic reconnection, we found an asymmetric structure in the out-of-plane magnetic field during the evolution of reconnection, which can be understood by a coupling of the Hall effect and the differential rotation. We also found a migration of X-point whose direction is determined only by an initial sign of J{sub 0}×?{sub 0}, where J{sub 0} is the initial current density in the neutral sheet and ?{sub 0} is the rotational vector of the background Keplerian rotation. Associated with the migration of X-point, we also found a significant enhancement of the perpendicular magnetic field compared to an ordinary MRI. MRI-Magnetic reconnection coupling and the resulting magnetic field enhancement can be an effective process to sustain a strong turbulence in the accretion disk and to a transport of angular momentum.
Jia Zhang [Department of Materials Processing Engineering, School of Materials Science and Engineering, Dalian University of Technology, Linggong Road 2, Ganjingzi District, Dalian 116085, Liaoning Province (China); Duan Yuping, E-mail: duanyp@dlut.edu.c [Department of Materials Processing Engineering, School of Materials Science and Engineering, Dalian University of Technology, Linggong Road 2, Ganjingzi District, Dalian 116085, Liaoning Province (China); Li Shuqing, E-mail: lsq6668@126.co [Beijing Aeronautical Manufacturing Technology Research Institute, 1 Jun Zhuang east Road, Chaoyang District, Beijing 100024 (China); Li Xiaogang, E-mail: lixiaogang99@263.ne [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Liu Shunhua [Department of Materials Processing Engineering, School of Materials Science and Engineering, Dalian University of Technology, Linggong Road 2, Ganjingzi District, Dalian 116085, Liaoning Province (China)
2010-07-15
MnO{sub 2} with a sea urchin-like ball chain shape was first synthesized in a high magnetic field via a simple chemical process, and a mechanism for the formation of this grain shape was discussed. The as-synthesized samples were characterized by XRD, SEM, TEM, and vector network analysis. The dielectric constant and the loss tangent clearly decreased under a magnetic field. The magnetic loss tangent and the imaginary part of the magnetic permeability increased substantially. Furthermore, the theoretically calculated values of reflection loss showed that the absorption peaks shifted to a higher frequency with increases in the magnetic field strength. - Graphical abstract: MnO{sub 2} with a sea urchin-like ball chain shape is first synthesized in a high magnetic field via a simple hydrothermal route.
Rosas-Ortiz, Jose Oscar
REVISTA MEXICANA DE FÂ´ISICA S 53 (2) 103Â109 FEBRERO 2007 Gamow vectors and Supersymmetric Quantum
Conformal symmetry breaking and degeneracy of high-lying unflavored mesons
Mariana Kirchbach; Adrian Pallares-Rivera; Cliffor Compean; Alfredo Raya
2012-07-13
We show that though conformal symmetry can be broken by the dilaton, such can happen without breaking the conformal degeneracy patterns in the spectra. We departure from R^1XS^3 slicing of AdS_5 noticing that the inverse radius, R, of S^3 relates to the temperature of the deconfinement phase transition and has to satisfy, \\hbar c/R >> \\Lambda_{QCD}. We then focus on the eigenvalue problem of the S^3 conformal Laplacian, given by 1/R^2 (K^2+1), with K^2 standing for the Casimir invariant of the so(4) algebra. Such a spectrum is characterized by a (K+1)^2 fold degeneracy of its levels, with K\\in [0,\\infty). We then break the conformal S^3 metric as, d\\tilde{s}^2=e^{-b\\chi} ((1+b^2/4) d\\chi^2 +\\sin^2\\chi (d\\theta ^2 +\\sin^2\\theta d\\varphi ^2)), and attribute the symmetry breaking scale, b\\hbar^2c^2/R^2, to the dilaton. We show that such a metric deformation is equivalent to a breaking of the conformal curvature of S^3 by a term proportional to b\\cot \\chi, and that the perturbed conformal Laplacian is equivalent to (\\tilde{K}^2 +c_K), with c_K a representation constant, and \\tilde{K}^2 being again an so(4) Casimir invariant, but this time in a representation unitarily inequivalent to the 4D rotational. In effect, the spectra before and after the symmetry breaking are determined each by eigenvalues of a Casimir invariant of an so(4) algebra, a reason for which the degeneracies remain unaltered though the conformal group symmetry breaks at the level of the representation of its algebra. We fit the S^3 radius and the \\hbar^2c^2b/R^2 scale to the high-lying excitations in the spectra of the unflavored mesons, and observe the correct tendency of the \\hbar c /R=373 MeV value to notably exceed \\Lambda_{QCD}. The size of the symmetry breaking scale is calculated as \\hbar c \\sqrt{b}/R=673.7 MeV.
Low-lying excited states and nonradiative processes of 9-methyl-2-aminopurine
Trachsel, Maria A.; Lobsiger, Simon; Schär, Tobias; Leutwyler, Samuel
2014-01-28
The UV spectrum of the adenine analogue 9-methyl-2-aminopurine (9M-2AP) is investigated with one- and two-color resonant two-photon ionization spectroscopy at 0.3 and 0.05 cm{sup ?1} resolution in a supersonic jet. The electronic origin at 32 252 cm{sup ?1} exhibits methyl torsional subbands that originate from the 0A{sub 1}{sup ??} (l = 0) and 1E{sup ?} (l = ±1) torsional levels. These and further torsional bands that appear up to 0{sub 0}{sup 0}+230 cm{sup ?1} allow to fit the threefold (V{sub 3}) barriers of the torsional potentials as |V{sub 3}{sup ??}|=50 cm{sup ?1} in the S{sub 0} and |V{sub 3}{sup ?}|=126 cm{sup ?1} in the S{sub 1} state. Using the B3LYP density functional and correlated approximate second-order coupled cluster CC2 methods, the methyl orientation is calculated to be symmetric relative to the 2AP plane in both states, with barriers of V{sub 3}{sup ??}=20 cm{sup ?1} and V{sub 3}{sup ?}=115 cm{sup ?1}. The 0{sub 0}{sup 0} rotational band contour is 75% in-plane (a/b) polarized, characteristic for a dominantly long-axis {sup 1}??{sup *} excitation. The residual 25% c-axis polarization may indicate coupling of the {sup 1}??{sup *} to the close-lying {sup 1}n?{sup *} state, calculated at 4.00 and 4.01 eV with the CC2 method. However, the CC2 calculated {sup 1}n? oscillator strength is only 6% of that of the {sup 1}??{sup *} transition. The {sup 1}??{sup *} vibronic spectrum is very complex, showing about 40 bands within the lowest 500 cm{sup ?1}. The methyl torsion and the low-frequency out-of-plane ?{sub 1}{sup ?} and ?{sub 2}{sup ?} vibrations are strongly coupled in the {sup 1}??{sup *} state. This gives rise to many torsion-vibration combination bands built on out-of-plane fundamentals, which are without precedence in the {sup 1}??{sup *} spectrum of 9H-2-aminopurine [S. Lobsiger, R. K. Sinha, M. Trachsel, and S. Leutwyler, J. Chem. Phys. 134, 114307 (2011)]. From the Lorentzian broadening needed to fit the 0{sub 0}{sup 0} contour of 9M-2AP, the {sup 1}??{sup *} lifetime is ? ? 120 ps, reflecting a rapid nonradiative transition.
Biosensor method and system based on feature vector extraction
Greenbaum, Elias; Rodriguez, Jr., Miguel; Qi, Hairong; Wang, Xiaoling
2013-07-02
A system for biosensor-based detection of toxins includes providing at least one time-dependent control signal generated by a biosensor in a gas or liquid medium, and obtaining a time-dependent biosensor signal from the biosensor in the gas or liquid medium to be monitored or analyzed for the presence of one or more toxins selected from chemical, biological or radiological agents. The time-dependent biosensor signal is processed to obtain a plurality of feature vectors using at least one of amplitude statistics and a time-frequency analysis. At least one parameter relating to toxicity of the gas or liquid medium is then determined from the feature vectors based on reference to the control signal.
Biosensor method and system based on feature vector extraction
Greenbaum, Elias (Knoxville, TN); Rodriguez, Jr., Miguel (Oak Ridge, TN); Qi, Hairong (Knoxville, TN); Wang, Xiaoling (San Jose, CA)
2012-04-17
A method of biosensor-based detection of toxins comprises the steps of providing at least one time-dependent control signal generated by a biosensor in a gas or liquid medium, and obtaining a time-dependent biosensor signal from the biosensor in the gas or liquid medium to be monitored or analyzed for the presence of one or more toxins selected from chemical, biological or radiological agents. The time-dependent biosensor signal is processed to obtain a plurality of feature vectors using at least one of amplitude statistics and a time-frequency analysis. At least one parameter relating to toxicity of the gas or liquid medium is then determined from the feature vectors based on reference to the control signal.
An efficient parallel algorithm for matrix-vector multiplication
Hendrickson, B.; Leland, R.; Plimpton, S.
1993-03-01
The multiplication of a vector by a matrix is the kernel computation of many algorithms in scientific computation. A fast parallel algorithm for this calculation is therefore necessary if one is to make full use of the new generation of parallel supercomputers. This paper presents a high performance, parallel matrix-vector multiplication algorithm that is particularly well suited to hypercube multiprocessors. For an n x n matrix on p processors, the communication cost of this algorithm is O(n/[radical]p + log(p)), independent of the matrix sparsity pattern. The performance of the algorithm is demonstrated by employing it as the kernel in the well-known NAS conjugate gradient benchmark, where a run time of 6.09 seconds was observed. This is the best published performance on this benchmark achieved to date using a massively parallel supercomputer.
New techniques in 3D scalar and vector field visualization
Max, N.; Crawfis, R.; Becker, B.
1993-05-05
At Lawrence Livermore National Laboratory (LLNL) we have recently developed several techniques for volume visualization of scalar and vector fields, all of which use back-to-front compositing. The first renders volume density clouds by compositing polyhedral volume cells or their faces. The second is a ``splatting`` scheme which composites textures used to reconstruct the scalar or vector fields. One version calculates the necessary texture values in software, and another takes advantage of hardware texture mapping. The next technique renders contour surface polygons using semi-transparent textures, which adjust appropriately when the surfaces deform in a flow, or change topology. The final one renders the ``flow volume`` of smoke or dye tracer swept out by a fluid flowing through a small generating polygon. All of these techniques are applied to a climate model data set, to visualize cloud density and wind velocity.
Probability-theoretical analog of the vector Lyapunov function method
Nakonechnyi, A.N.
1995-01-01
The main ideas of the vector Lyapunov function (VLF) method were advanced in 1962 by Bellman and Matrosov. In this method, a Lyapunov function and a comparison equation are constructed for each subsystem. Then the dependences between the subsystems and the effect of external noise are allowed for by constructing a vector Lyapunov function (as a collection of the scalar Lyapunov functions of the subsystems) and an aggregate comparison function for the entire complex system. A probability-theoretical analog of this method for convergence analysis of stochastic approximation processes has been developed. The abstract approach proposed elsewhere eliminates all restrictions on the system phase space, the system trajectories, the class of Lyapunov functions, etc. The analysis focuses only on the conditions that relate sequences of Lyapunov function values with the derivative and ensure a particular type (mode, character) of stability. In our article, we extend this approach to the VLF method for discrete stochastic dynamic systems.
Observation of ?c1 Decays into Vector Meson Pairs ??, ?? and, ??
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Ablikim, M.; Achasov, M. N.; An, L.; An, Q.; An, Z. H.; Bai, J. Z.; Baldini, R.; Ban, Y.; Becker, J.; Berger, N.; et al
2011-08-22
Using (106±4)×10? ?(3686) events accumulated with the BESIII detector at the BEPCII e?e? collider, we present the first measurement of decays of ?c1 to vector meson pairs ??, ??, and ??. The branching fractions are measured to be (4.4±0.3±0.5)×10??, (6.0±0.3±0.7)×10??, and (2.2±0.6±0.2)×10??, for ?c1 ???, ??, and ??, respectively, which indicates that the hadron helicity selection rule is significantly violated in ?cJ decays. In addition, the measurement of ?cJ??? provides the first indication of the rate of doubly OZI-suppressed ?cJ decay. Finally, we present improved measurements for the branching fractions of ?c0 and ?c2 to vector meson pairs.
Parameter-insensitive kernel in extreme learning for non-linear support vector regression
Verleysen, Michel
Parameter-insensitive kernel in extreme learning for non-linear support vector regression Beno Available online 12 May 2011 Keywords: Extreme learning machine Support vector regression ELM kernel Infinite number of neurons a b s t r a c t Support vector regression (SVR) is a state-of-the-art method
Vector and Matrix Operations Programmed with UDFs in a Relational DBMS
Ordonez, Carlos
Vector and Matrix Operations Programmed with UDFs in a Relational DBMS Carlos Ordonez University, a relational DBMS provides limited capabilities to perform multidimensional statistical analysis, which re- quires manipulating vectors and matrices. In this work, we study how to extend a DBMS with basic vector
Lyapunov Vector Fields for Autonomous UAV Flight Control1 Dale A. Lawrence2
Frew, Eric W.
Lyapunov Vector Fields for Autonomous UAV Flight Control1 Dale A. Lawrence2 , Eric. W. Frew3 that incorporate Lyapunov stability properties to produce simple, globally stable vector fields in 3D. Use of the vector field is considered, using Lyapunov techniques to show global stability of heading and path
Feature Selection for Support Vector Regression in the Application of Building Energy Prediction
Paris-Sud XI, Université de
Feature Selection for Support Vector Regression in the Application of Building Energy Prediction--When using support vector regression to predict building energy consumption, since the energy influence and reduces the computational time. Keywords-support vector regression; feature selection; build- ing; energy
Gumhold, Stefan
Interactive Visualization of Volumetric Vector Fields Using Texture Based Particles Stefan Guthe This paper introduces a new approach to the visualization of volumetric vector fields with an adaptive problem of volumetric vector field visualization, as the human eye can trace an animated particle even
Vector processing enhancements for real-time image analysis.
Shoaf, S.; APS Engineering Support Division
2008-01-01
A real-time image analysis system was developed for beam imaging diagnostics. An Apple Power Mac G5 with an Active Silicon LFG frame grabber was used to capture video images that were processed and analyzed. Software routines were created to utilize vector-processing hardware to reduce the time to process images as compared to conventional methods. These improvements allow for more advanced image processing diagnostics to be performed in real time.
Classifier based on support vector machine for JET plasma configurations
Dormido-Canto, S.; Farias, G.; Dormido, R.; Sanchez, J.; Duro, N.; Vargas, H.
2008-10-15
The last flux surface can be used to identify the plasma configuration of discharges. For automated recognition of JET configurations, a learning system based on support vector machines has been developed. Each configuration is described by 12 geometrical parameters. A multiclass system has been developed by means of the one-versus-the-rest approach. Results with eight simultaneous classes (plasma configurations) show a success rate close to 100%.
Controllable scattering of vector Bose-Einstein solitons
Babarro, Judit; Paz-Alonso, Maria J.; Michinel, Humberto; Salgueiro, Jose R.; Olivieri, David N.
2005-04-01
We show the possibility of producing matter-wave switching devices by using Manakov interactions between vector matter-wave solitons using two-species Bose-Einstein condensates (BECs). Our results establish the experimental parameters for three interaction regimes in two-species BECs: symmetric and asymmetric splitting, down-switching, and up-switching. We have studied the dependence upon the initial conditions and the kind of interaction between the two matter-wave solitons.
Texture splats for 3D vector and scalar field visualization
Crawfis, R.A.; Max, N.
1993-04-06
Volume Visualization is becoming an important tool for understanding large 3D datasets. A popular technique for volume rendering is known as splatting. With new hardware architectures offering substantial improvements in the performance of rendering texture mapped objects, we present textured splats. An ideal reconstruction function for 3D signals is developed which can be used as a texture map for a splat. Extensions to the basic splatting technique are then developed to additionally represent vector fields.
Methods of treating Parkinson's disease using viral vectors
Bankiewicz, Krys; Cunningham, Janet
2012-11-13
Methods of delivering viral vectors, particularly recombinant AAV virions, to the central nervous system (CNS) are provided for the treatment of CNS disorders, particularly those disorders which involve the neurotransmitter dopamine. The methods entail providing rAAV virions that comprise a transgene encoding aromatic amino acid decarboxylase (AADC) and administering the virions to the brain of a mammal using a non-manual pump.
Transposon-containing DNA cloning vector and uses thereof
Berg, Claire M. (W. Willington, CT); Berg, Douglas E. (St. Louis, MO); Wang, Gan (Storrs, CT)
1997-01-01
The present invention discloses a rapid method of restriction mapping, sequencing or localizing genetic features in a segment of deoxyribonucleic acid (DNA) that is up to 42 kb in size. The method in part comprises cloning of the DNA segment in a specialized cloning vector and then isolating nested deletions in either direction in vivo by intramolecular transposition into the cloned DNA. A plasmid has been prepared and disclosed.
Transposon-containing DNA cloning vector and uses thereof
Berg, C.M.; Berg, D.E.; Wang, G.
1997-07-08
The present invention discloses a rapid method of restriction mapping, sequencing or localizing genetic features in a segment of deoxyribonucleic acid (DNA) that is up to 42 kb in size. The method in part comprises cloning of the DNA segment in a specialized cloning vector and then isolating nested deletions in either direction in vivo by intramolecular transposition into the cloned DNA. A plasmid has been prepared and disclosed. 4 figs.
Passive magnetic bearing configurations
Post, Richard F. (Walnut Creek, CA)
2011-01-25
A journal bearing provides vertical and radial stability to a rotor of a passive magnetic bearing system when the rotor is not rotating and when it is rotating. In the passive magnetic bearing system, the rotor has a vertical axis of rotation. Without the journal bearing, the rotor is vertically and radially unstable when stationary, and is vertically stable and radially unstable when rotating.
Superconducting Magnet Division
Ohta, Shigemi
Superconducting Magnet Division MAGNETIC DESIGN OF E-LENS SOLENOID AND CORRECTOR SYSTEM FOR RHIC* R.6 A gun collectors gun Combined Horizontal and Vertical Corrector Design Both types of dipole correctors. Gupta, M. Anerella, W. Fischer, G. Ganetis, X. Gu, A. Ghosh, A. Jain, P. Kovach, A. Marone, S. Plate, A
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.
Experimental investigation of magnetic anisotropy in spin vortex discs
Garraud, N. Arnold, D. P.
2014-05-07
We present experimental 2D vector vibrating sample magnetometer measurements to demonstrate the shape anisotropy effects occurring in micrometer-diameter supermalloy spin vortex discs. Measurements made for different disc sizes and orientations confirm the out-of-plane susceptibility is several orders of magnitude smaller than the in-plane susceptibility. These results validate with a high certitude that spin vortices with high diameter to thickness ratio retain in-plane-only magnetization, even when subjected to fields in the out-of-plane direction. These results contribute to further computational simulations of the dynamics of spin vortex structures in colloidal suspensions where external fields may be applied in any arbitrary direction.
Higgs constraints from vector boson fusion and scattering
John M. Campbell; R. Keith Ellis
2015-02-10
We present results on 4-lepton + 2-jet production, the partonic processes most commonly described as vector boson pair production in the Vector Boson Fusion (VBF) mode. This final state contains diagrams that are mediated by Higgs boson exchange. We focus particularly on the high-mass behaviour of the Higgs boson mediated diagrams, which unlike on-shell production, gives information about the Higgs couplings without assumptions on the Higgs boson total width. We assess the sensitivity of the high-mass region to Higgs coupling strengths, considering all vector boson pair channels, $W^-W^+$, $W^\\pm W^\\pm$, $W^\\pm Z$ and $ZZ$. Because of the small background, the most promising mode is $W^+ W^+$ which has sensitivity to Higgs couplings because of Higgs boson exchange in the $t$-channel. Using the Caola-Melnikov (CM) method, the off-shell couplings can be interpreted as bounds on the Higgs boson total width. We estimate the bound that can be obtained with current data, as well as the bounds that could be obtained at $\\sqrt{s}=13$~TeV in the VBF channel for data samples of 100 and 300 fb$^{-1}$. The CM method has already been successfully applied in the gluon fusion (GGF) production channel. The VBF production channel gives important complementary information, because both production and decay of the Higgs boson occur already at tree graph level.
Vector potentials in gauge theories in flat spacetime
C. W. Wong
2015-09-09
A recent suggestion that vector potentials in electrodynamics (ED) are nontensorial objects under 4D frame rotations is found to be both unnecessary and confusing. As traditionally used in ED, a vector potential $A$ always transforms homogeneously under 4D rotations in spacetime, but if the gauge is changed by the rotation, one can restore the gauge back to the original gauge by adding an inhomogeneous term. It is then "not a 4-vector", but two: one for rotation and one for translation. For such a gauge, it is much more important to preserve {\\it explicit} homogeneous Lorentz covariance by simply skipping the troublesome gauge-restoration step. A gauge-independent separation of $A$ into a dynamical term and a non-dynamical term in Abelian gauge theories is re-defined more generally as the terms caused by the presence and absence respectively of the 4-current term in the inhomogeneous Maxwell equations for $A$. Such a separation {\\it cannot} in general be extended to non-Abelian theories where $A$ satisfies nonlinear differential equations. However, in the linearized iterative solution that is perturbation theory, the usual Abelian quantizations in the usual gauges can be used. Some nonlinear complications are briefly reviewed.
Higgs constraints from vector boson fusion and scattering
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Campbell, John M.; Ellis, R. Keith
2015-04-07
We present results on 4-lepton + 2-jet production, the partonic processes most commonly described as vector boson pair production in the Vector Boson Fusion (VBF) mode. This final state contains diagrams that are mediated by Higgs boson exchange. We focus particularly on the high-mass behaviour of the Higgs boson mediated diagrams, which unlike on-shell production, gives information about the Higgs couplings without assumptions on the Higgs boson total width. We assess the sensitivity of the high-mass region to Higgs coupling strengths, considering all vector boson pair channels, W?W?, W±W±, W±Z and ZZ. Because of the small background, the most promisingmore »mode is W?W? which has sensitivity to Higgs couplings because of Higgs boson exchange in the t-channel. Using the Caola-Melnikov (CM) method, the off-shell couplings can be interpreted as bounds on the Higgs boson total width. We estimate the bound that can be obtained with current data, as well as the bounds that could be obtained at ?s = 13TeV in the VBF channel for data samples of 100 and 300 fb?¹. The CM method has already been successfully applied in the gluon fusion (GGF) production channel. The VBF production channel gives important complementary information, because both production and decay of the Higgs boson occur already at tree graph level.« less
Thorn, Craig E. (Wading River, NY); Chasman, Chellis (Setauket, NY); Baltz, Anthony J. (Coram, NY)
1984-04-24
An improved magnet which more easily provides a radially increasing magnetic field, as well as reduced fringe field and requires less power for a given field intensity. The subject invention comprises a pair of spaced, opposed magnetic poles which further comprise a pair of pole roots, each having a pole tip attached to its center. The pole tips define the gap between the magnetic poles and at least a portion of each pole tip is separated from its associated pole root. The separation begins at a predetermined distance from the center of the pole root and increases with increasing radial distance while being constant with azimuth within that portion. Magnets in accordance with the subject invention have been found to be particularly advantageous for use in large isochronous cyclotrons.
Thorn, C.E.; Chasman, C.; Baltz, A.J.
1981-11-19
An improved magnet more easily provides a radially increasing magnetic field, as well as reduced fringe field and requires less power for a given field intensity. The subject invention comprises a pair of spaced, opposed magnetic poles which further comprise a pair of pole roots, each having a pole tip attached to its center. The pole tips define the gap between the magnetic poles and at least a portion of each pole tip is separated from its associated pole root. The separation begins at a predetermined distance from the center of the pole root and increases with increasing radial distance while being constant with azimuth within that portion. Magnets in accordance with the subject invention have been found to be particularly advantageous for use in large isochronous cyclotrons.
Bioinspired Design : : Magnetic Freeze Casting
Porter, Michael Martin
2014-01-01
30 CHAPTER 3: FREEZE CASTING: A94 CHAPTER 5: MAGNETIC FREEZE CASTING INSPIRED BY98 5.2.1. Magnetic freeze casting
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.
Lensless Imaging of Magnetic Nanostructures
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Print Magnetism is useful for many devices and techniques, from electric motors and computer hard drives to magnetic resonance imaging used in medicine. By studying...
QUENCHES IN LARGE SUPERCONDUCTING MAGNETS
Eberhard, P.H.
2010-01-01
QUENCHES IN LARGE SUPERCONDUCTING MAGNETS. P. H. Eberhard,Study of an Unprotected Superconducting Coil Going Normal,"Method for Testing Superconducting Magnets," LBL Physics
Large Magnetization at Carbon Surfaces
Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)
Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...
An Electron Fixed Target Experiment to Search for a New Vector Boson A' Decaying to e+e-
Rouven Essig; Philip Schuster; Natalia Toro; Bogdan Wojtsekhowski
2010-01-15
We describe an experiment to search for a new vector boson A' with weak coupling alpha' > 6 x 10^{-8} alpha to electrons (alpha=e^2/4pi) in the mass range 65 MeV Spectrometer and the septum magnet in Hall A. With a ~1 month run, APEX will achieve very good sensitivity because the statistics of e+e- pairs will be ~10,000 times larger in the explored mass range than any previous search for the A' boson. These statistics and the excellent mass resolution of the spectrometers allow sensitivity to alpha'/alpha one to three orders of magnitude below current limits, in a region of parameter space of great theoretical and phenomenological interest. Similar experiments could also be performed at other facilities, such as the Mainz Microtron.
Jeremy S. Heyl; Lars Hernquist
1996-08-25
We calculate the reaction cross-sections for the fusion of hydrogen and deuterium in strong magnetic fields as are believed to exist in the atmospheres of neutron stars. We find that in the presence of a strong magnetic field ($B \\gsim 10^{12}$G), the reaction rates are many orders of magnitude higher than in the unmagnetized case. The fusion of both protons and deuterons are important over a neutron star's lifetime for ultrastrong magnetic fields ($B \\sim 10^{16}$G). The enhancement may have dramatic effects on thermonuclear runaways and bursts on the surfaces of neutron stars.
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.
Modelling solar low-lying cool loops with optically thick radiative losses
Sasso, C; Spadaro, D
2015-01-01
We investigate the increase of the DEM (differential emission measure) towards the chromosphere due to small and cool magnetic loops (height $\\lesssim8$~Mm, $T\\lesssim10^5$~K). In a previous paper we analysed the conditions of existence and stability of these loops through hydrodynamic simulations, focusing on their dependence on the details of the optically thin radiative loss function used. In this paper, we extend those hydrodynamic simulations to verify if this class of loops exists and it is stable when using an optically thick radiative loss function. We study two cases: constant background heating and a heating depending on the density. The contribution to the transition region EUV output of these loops is also calculated and presented. We find that stable, quasi-static cool loops can be obtained by using an optically thick radiative loss function and a background heating depending on the density. The DEMs of these loops, however, fail to reproduce the observed DEM for temperatures between $4.6<\\log...
Emergence of Small-Scale Magnetic Loops in the Quiet Sun Internetwork
R. Centeno; H. Socas-Navarro; B. Lites; M. Kubo; Z. Frank; R. Shine; T. Tarbell; A. Title; K. Ichimoto; S. Tsuneta; Y. Katsukawa; Y. Suematsu; T. Shimizu; S. Nagata
2007-08-06
We study the emergence of magnetic flux at very small spatial scales (less than 2 arcsec) in the quiet Sun internetwork. To this aim, a time series of spectropolarimetric maps was taken at disk center using the instrument SP/SOT on board Hinode. The LTE inversion of the full Stokes vector measured in the Fe I 6301 and 6302 A lines allows us to retrieve the magnetic flux and topology in the region of study. In the example presented here, the magnetic flux emerges within a granular structure. The horizontal magnetic field appears prior to any significant amount of vertical field. As time goes on, the traces of the horizontal field disappear while the the vertical dipoles drift -carried by the plasma motions- towards the surrounding intergranular lanes. These events take place within typical granulation timescales.
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.
Lagrangians with electric and magnetic charges of N=2 supersymmetric gauge theories
Mathijs de Vroome; Bernard de Wit
2007-07-18
General Lagrangians are constructed for N=2 supersymmetric gauge theories in four space-time dimensions involving gauge groups with (non-abelian) electric and magnetic charges. The charges induce a scalar potential, which, when the charges are regarded as spurionic quantities, is invariant under electric/magnetic duality. The resulting theories are especially relevant for supergravity, but details of the extension to local supersymmetry will be discussed elsewhere. The results include the coupling to hypermultiplets. Without the latter, it is demonstrated how an off-shell representation can be constructed based on vector and tensor supermultiplets.
Knopf, Dan
MATRIX OPERATIONS, TRANSFORMATIONS Given a vector in and an matrix we've learned then be expressed very compactly the terms of a matrix equation , for instance. Now we want to start with an matrix and develop the very important idea of thinking of as 'mapping' or 'transforming' any vector
Quark matter subject to strong magnetic fields: phase diagram and applications
Débora P. Menezes; Marcus B. Pinto; Constança Providência; Pedro Costa; Márcio Ferreira; Luis B. Castro
2014-09-22
In the present work we are interested in understanding various properties of quark matter subject to strong magnetic fields described by the Nambu-Jona-Lasinio model with Polyakov loop. We start by analysing the differences arising from two different vector interactions in the Lagrangian densities, at zero temperature, and apply the results to stellar matter. We then investigate the position of the critical end point for different chemical potential and density scenarios.
Modular tokamak magnetic system
Yang, Tien-Fang (Wayland, MA)
1988-01-01
A modular tokamak system comprised of a plurality of interlocking moldules. Each module is comprised of a vacuum vessel section, a toroidal field coil, moldular saddle coils which generate a poloidal magnetic field and ohmic heating coils.
Geometrically frustrated quantum magnets
NikoliÄ‡ , Predrag, 1974-
2004-01-01
(cont.) more general lessons on frustrated quantum magnetism. At the end, we demonstrate some new mathematical tools on two other frustrated two-dimensional systems, and summarize our conclusions, with an outlook to remaining ...
Meyer, R.E.
1993-03-09
A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.
Magnetic Catalysis in Graphene
Christopher Winterowd; Carleton DeTar; Savvas Zafeiropoulos
2015-09-22
One of the most important developments in condensed matter physics in recent years has been the discovery and characterization of graphene. A two-dimensional layer of Carbon arranged in a hexagonal lattice, graphene exhibits many interesting electronic properties, most notably that the low energy excitations behave as massless Dirac fermions. These excitations interact strongly via the Coulomb interaction and thus non-perturbative methods are necessary. Using methods borrowed from lattice QCD, we study the graphene effective theory in the presence of an external magnetic field. Graphene, along with other $(2+1)$-dimensional field theories, has been predicted to undergo spontaneous breaking of flavor symmetry including the formation of a gap as a result of the external magnetic field. This phenomenon is known as magnetic catalysis. Our study investigates magnetic catalysis using a fully non-perturbative approach.
Magnetic Catalysis in Graphene
Winterowd, Christopher; Zafeiropoulos, Savvas
2015-01-01
One of the most important developments in condensed matter physics in recent years has been the discovery and characterization of graphene. A two-dimensional layer of Carbon arranged in a hexagonal lattice, graphene exhibits many interesting electronic properties, most notably that the low energy excitations behave as massless Dirac fermions. These excitations interact strongly via the Coulomb interaction and thus non-perturbative methods are necessary. Using methods borrowed from lattice QCD, we study the graphene effective theory in the presence of an external magnetic field. Graphene, along with other $(2+1)$-dimensional field theories, has been predicted to undergo spontaneous breaking of flavor symmetry including the formation of a gap as a result of the external magnetic field. This phenomenon is known as magnetic catalysis. Our study investigates magnetic catalysis using a fully non-perturbative approach.
Meyer, Ross E. (Los Alamos, NM)
1993-01-01
A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.
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
Betti Numbers of Graded Modules and Cohomology of Vector Bundles
Eisenbud, David
2007-01-01
Mats Boij and Jonas Soederberg (math.AC/0611081) have conjectured that the Betti table of a Cohen-Macaulay module over a polynomial ring can be decomposed in a certain way as a positive linear combination of Betti tables of modules with pure resolutions. We prove, in characteristic zero, a strengthened form of their conjecture. Applications include a proof (in characteristic zero) of the Multiplicity Conjecture of Huneke and Srinivasan, a proof of the convexity of a fan naturally associated to the Young lattice, and bounds on the possible cohomology modules of vector bundles on projective spaces.
A stable Higgs portal with vector dark matter
Mateusz Duch; Bohdan Grzadkowski; Moritz McGarrie
2015-09-23
We explore an extension of the Standard Model by an additional U (1) gauge group and a complex scalar Higgs portal. As the scalar is charged under this gauge factor this simple model supplies a vector dark matter candidate satisfying the observed relic abundance and limits from direct dark matter searches. An additional Higgs-like state, that may be heavier or lighter than the observed Higgs, is present and satisfies LEP and LHC bounds whilst allowing for absolute stability of the electroweak vacuum in a range of parameter space.
Double vector meson production in the International Linear Collider
F. Carvalho; V. P. Goncalves; B. D. Moreira; F. S. Navarra
2015-04-17
In this paper we study double vector meson production in $\\gamma \\gamma$ interactions at high energies and, using the color dipole picture, estimate the main observables which can be probed at the International Linear Collider (ILC). The total $\\gamma (Q_1^2) + \\gamma (Q_2^2) \\rightarrow V_1 + V_2$ cross-sections for $V_i = \\rho$, $\\phi$, $J/\\psi$ and $\\Upsilon$ are computed and the energy and virtuality dependencies are studied in detail. Our results demonstrate that the experimental analysis of this process is feasible at the ILC and it can be useful to constrain the QCD dynamics at high energies.
Characteristic Lyapunov vectors in chaotic time-delayed systems
Diego Pazó; Juan M. López
2011-01-14
We compute Lyapunov vectors (LVs) corresponding to the largest Lyapunov exponents in delay-differential equations with large time delay. We find that characteristic LVs, and backward (Gram-Schmidt) LVs, exhibit long-range correlations, identical to those already observed in dissipative extended systems. In addition we give numerical and theoretical support to the hypothesis that the main LV belongs, under a suitable transformation, to the universality class of the Kardar-Parisi-Zhang equation. These facts indicate that in the large delay limit (an important class of) delayed equations behave exactly as dissipative systems with spatiotemporal chaos.
Double vector meson production in the International Linear Collider
Carvalho, F; Moreira, B D; Navarra, F S
2015-01-01
In this paper we study double vector meson production in $\\gamma \\gamma$ interactions at high energies and, using the color dipole picture, estimate the main observables which can be probed at the International Linear Collider (ILC). The total $\\gamma (Q_1^2) + \\gamma (Q_2^2) \\rightarrow V_1 + V_2$ cross-sections for $V_i = \\rho$, $\\phi$, $J/\\psi$ and $\\Upsilon$ are computed and the energy and virtuality dependencies are studied in detail. Our results demonstrate that the experimental analysis of this process is feasible at the ILC and it can be useful to constrain the QCD dynamics at high energies.
Savici, Andrei T [ORNL; Granroth, Garrett E [ORNL; Broholm, Collin L [ORNL; Bird, Mark D [ORNL; Lee, Young S [ORNL
2010-01-01
ZEEMANS, a new instrument proposed for the Spallation Neutron Source (SNS) at Oak Ridge, will provide highest available magnetic elds for neutron scattering experiments. The unique capabilities of the magnet, large size and required connection to utilities demand a versatile instrument, able of performing diraction (powder and single crystal), SANS, re ectometry, and inelastic spectrometry, with minimal modications between congurations. In this paper we present preliminary design features for ZEEMANS. Monte Carlo simulations and analytical calculations were used to study its expected performance.
Nance, Thomas A. (Aiken, SC)
2009-08-18
A quick connect/disconnect coupling apparatus is provided in which a base member is engaged by a locking housing through a series of interengagement pins. The pins maintain the shaft in a locked position. Upon exposure to an appropriately positioned magnetic field, pins are removed a sufficient distance such that the shaft may be withdrawn from the locking housing. The ability to lock and unlock the connector assembly requires no additional tools or parts apart from a magnetic key.
Berman, S.M.; Richardson R.W.
1983-12-29
The radiant emission of a mercury-argon discharge in a fluorescent lamp assembly is enhanced by providing means for establishing a magnetic field with lines of force along the path of electron flow through the bulb of the lamp assembly, to provide Zeeman splitting of the ultraviolet spectral line. Optimum results are obtained when the magnetic field strength causes a Zeeman splitting of approximately 1.7 times the thermal line width.
Theoretical spectroscopy study of the low-lying electronic states of UX and UX+, X = F and Cl
DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)
Bross, David H.; Peterson, Kirk A.
2015-11-13
Spectroscopic constants (Te, re, B0, ?e, ?exe) have been calculated for the low-lying electronic states of UF, UF+, UCl, and UCl+ using complete active space 2nd-order perturbation theory (CASPT2), with a series of correlation consistent basis sets. The latter included those based on both pseudopotential (PP) and all-electron Douglas-Kroll-Hess (DK) Hamiltonians for the U atom. Spin orbit effects were included a posteri using the state interacting method using both PP and Breit Pauli (BP) operators, as well as from exact two-component (X2C) methods for U+ and UF+. Complete basis set (CBS) limits were obtained by extrapolation where possible and themore »PP and BP calculations were compared at their respective CBS limits. The PP-based method was shown to be reliable in calculating spectroscopic constants, in particular when using the state interacting method with CASPT2 energies (SO-CASPT2). The two component calculations were limited by computational resources and could not include electron correlation from the nominally closed shell 6s and 6p orbitals of U. UF and UCl were both calculated to have ?=9/2 ground states. The first excited state of UCl was calculated to be an ?=7/2 state at 78 cm-1 as opposed to the same state at 435 cm-1 in UF, and the other low-lying states of UCl showed a similar compression relative to UF. Likewise UF+ and UCl+ both have ?=4 ground states and the manifold of low-lying excited ? = 3, 2, 1, 0 states were energetically closer together in UCl+ than in UF+, ranging up to 776 cm-1 in UF+ and only 438 cm-1 in UCl+. As in previous research, the final PP-based SO-CASPT2 results for UF+ and UF agree well with experiment, and are expected to be predictive for UCl and UCl+, which are reported here for the first time.« less
Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization
Doughty, Frank C. (Plano, TX); Spencer, John E. (Plano, TX)
2000-12-19
In a plasma-producing device, an optimized magnet field for electron cyclotron resonance plasma generation is provided by a shaped pole piece. The shaped pole piece adjusts spacing between the magnet and the resonance zone, creates a convex or concave resonance zone, and decreases stray fields between the resonance zone and the workpiece. For a cylindrical permanent magnet, the pole piece includes a disk adjacent the magnet together with an annular cylindrical sidewall structure axially aligned with the magnet and extending from the base around the permanent magnet. The pole piece directs magnetic field lines into the resonance zone, moving the resonance zone further from the face of the magnet. Additional permanent magnets or magnet arrays may be utilized to control field contours on a local scale. Rather than a permeable material, the sidewall structure may be composed of an annular cylindrical magnetic material having a polarity opposite that of the permanent magnet, creating convex regions in the resonance zone. An annular disk-shaped recurve section at the end of the sidewall structure forms magnetic mirrors keeping the plasma off the pole piece. A recurve section composed of magnetic material having a radial polarity forms convex regions and/or magnetic mirrors within the resonance zone.
Low-lying isomeric state in {sup 80}Ga from the {beta}{sup -} decay of {sup 80}Zn
LicA, R.; Marginean, N.; Ghita, D.G.; and others
2012-10-20
A new level scheme was constructed for {sup 80}Ga which is significantly different from the one previously reported. The excitation energy of a new low-lying state recently reported in [2] was identified at 22.4 keV. Properties of the level scheme suggest that the ground state has spin J = 6 and the first excited state has spin J = 3. The spin assignments are in agreement with laser spectroscopy values previously measured. Our work provides the first evidence for the J = 6 being the ground state.
Freely oriented portable superconducting magnet
Schmierer, Eric N. (Los Alamos, NM); Prenger, F. Coyne (Los Alamos, NM); Hill, Dallas D. (Los Alamos, NM)
2010-01-12
A freely oriented portable superconducting magnet is disclosed. Coolant is supplied to the superconducting magnet from a repository separate from the magnet, enabling portability of the magnet. A plurality of support assemblies structurally anchor and thermally isolate the magnet within a thermal shield. A plurality of support assemblies structurally anchor and thermally isolate the thermal shield within a vacuum vessel. The support assemblies restrain movement of the magnet resulting from energizing and cooldown, as well as from changes in orientation, enabling the magnet to be freely orientable.
MAGNETIC NONPOTENTIALITY IN PHOTOSPHERIC ACTIVE REGIONS AS A PREDICTOR OF SOLAR FLARES
Yang Xiao; Lin Ganghua; Zhang Hongqi; Mao Xinjie
2013-09-10
Based on several magnetic nonpotentiality parameters obtained from the vector photospheric active region magnetograms obtained with the Solar Magnetic Field Telescope at the Huairou Solar Observing Station over two solar cycles, a machine learning model has been constructed to predict the occurrence of flares in the corresponding active region within a certain time window. The Support Vector Classifier, a widely used general classifier, is applied to build and test the prediction models. Several classical verification measures are adopted to assess the quality of the predictions. We investigate different flare levels within various time windows, and thus it is possible to estimate the rough classes and erupting times of flares for particular active regions. Several combinations of predictors have been tested in the experiments. The True Skill Statistics are higher than 0.36 in 97% of cases and the Heidke Skill Scores range from 0.23 to 0.48. The predictors derived from longitudinal magnetic fields do perform well, however, they are less sensitive in predicting large flares. Employing the nonpotentiality predictors from vector fields improves the performance of predicting large flares of magnitude {>=}M5.0 and {>=}X1.0.
Neumark, Daniel M.
Study of the low-lying states of Ge2 and Ge2 using negative ion zero electron kinetic energy The low-lying states of Ge2 and Ge2 are probed using negative ion zero electron kinetic energy ZEKE spectroscopy. The ZEKE spectrum of Ge2 yields an electron affinity of 2.035 0.001 eV for Ge2, as well as term
The (magnetized) effective QCD phase diagram
Alejandro Ayala
2015-09-02
I present the highlights of a recent study of the effective QCD phase diagram on the temperature T and quark chemical potential mu plane, where the strong interactions are modeled using the linear sigma model coupled to quarks. The phase transition line is found from the effective potential at finite T and mu taking into account the plasma screening effects. We find the location of the critical end point (CEP) to be (mu^CEP/T_c,T^CEP/T_c) \\sim (1.2,0.8), where T_c is the (pseudo)critical temperature for the crossover phase transition at vanishing mu. This location lies within the region found by lattice inspired calculations. Since the linear sigma model does not exhibit confinement, I argue that the location is due to the proper treatment of the plasma screening effects and not to the size of the confining scale. I also comment on the extension of this study to determine the dependence of the CEP's location on the strength of an external magnetic field.
Combined dispersive/interference spectroscopy for producing a vector spectrum
Erskine, David J. (Oakland, CA)
2002-01-01
A method of measuring the spectral properties of broadband waves that combines interferometry with a wavelength disperser having many spectral channels to produce a fringing spectrum. Spectral mapping, Doppler shifts, metrology of angles, distances and secondary effects such as temperature, pressure, and acceleration which change an interferometer cavity length can be measured accurately by a compact instrument using broadband illumination. Broadband illumination avoids the fringe skip ambiguities of monochromatic waves. The interferometer provides arbitrarily high spectral resolution, simple instrument response, compactness, low cost, high field of view and high efficiency. The inclusion of a disperser increases fringe visibility and signal to noise ratio over an interferometer used alone for broadband waves. The fringing spectrum is represented as a wavelength dependent 2-d vector, which describes the fringe amplitude and phase. Vector mathematics such as generalized dot products rapidly computes average broadband phase shifts to high accuracy. A Moire effect between the interferometer's sinusoidal transmission and the illumination heterodynes high resolution spectral detail to low spectral detail, allowing the use of a low resolution disperser. Multiple parallel interferometer cavities of fixed delay allow the instantaneous mapping of a spectrum, with an instrument more compact for the same spectral resolution than a conventional dispersive spectrometer, and not requiring a scanning delay.
Vector spectral functions and transport properties in quenched QCD
Heng-Tong Ding; Olaf Kaczmarek; Florian Meyer
2014-12-18
We present new results on the reconstruction of mesonic spectral functions for three temperatures $1.1T_c$, $1.2T_c$ and $1.4T_c$ in quenched QCD. Making use of non-perturbatively improved clover Wilson valence quarks allows for a clean extrapolation of correlator data to the continuum limit. For the case of vanishing momentum the spectral function is obtained by fitting the data to a well motivated ansatz, using the full covariance matrix of the continuum extrapolated data in the fit. We found that vector correlation function is almost temperature independent in the current temperature window. The electrical conductivity of the hot medium, related to the origin of the vector spectral function at zero momentum, is computed from the resulting parameters at all three temperatures, leading to an estimate of $0.2C_{em}\\lesssim \\sigma/T\\lesssim0.4C_{em}$. The dilepton rates resulting from the obtained spectral functions show no significant temperature dependence.
Exclusive Vector Meson Production in Relativistic Heavy Ion Collisions
Spencer Klein; Joakim Nystrand
1999-02-06
Exclusive vector meson production reactions such as $Au + Au \\to Au + Au + V$, where $V=\\rho, \\omega, \\phi$ or $J/\\psi$ can proceed through photon-Pomeron and photon-meson interactions. Photons from the electromagnetic field of one nucleus interact coherently with the other nucleus. Photonuclear cross sections are scaled from $\\gamma p$ data, and convoluted with the photon spectrum to find the exclusive rates. The cross sections at the RHIC and LHC heavy ion colliders are huge, 10% of the total hadronic cross section at RHIC, and 50% at LHC. These accelerators may be useful as vector meson factories. With iodine beams at RHIC, 640 $\\rho$ are produced each second (10^{10}/year); with calcium at the LHC the rate is 240 kHz. The $\\phi$ rates are 39 Hz at RHIC and 15 kHz at LHC, while the $J/\\psi$ rate is 0.3 Hz at RHIC and 780 Hz at the LHC. Because of the coherent couplings, the reactions kinematics are similar to coherent two-photon interactions; we discuss the interplay between the two reactions.
Real-time individualized training vectors for experiential learning.
Willis, Matt; Tucker, Eilish Marie; Raybourn, Elaine Marie; Glickman, Matthew R.; Fabian, Nathan
2011-01-01
Military training utilizing serious games or virtual worlds potentially generate data that can be mined to better understand how trainees learn in experiential exercises. Few data mining approaches for deployed military training games exist. Opportunities exist to collect and analyze these data, as well as to construct a full-history learner model. Outcomes discussed in the present document include results from a quasi-experimental research study on military game-based experiential learning, the deployment of an online game for training evidence collection, and results from a proof-of-concept pilot study on the development of individualized training vectors. This Lab Directed Research & Development (LDRD) project leveraged products within projects, such as Titan (Network Grand Challenge), Real-Time Feedback and Evaluation System, (America's Army Adaptive Thinking and Leadership, DARWARS Ambush! NK), and Dynamic Bayesian Networks to investigate whether machine learning capabilities could perform real-time, in-game similarity vectors of learner performance, toward adaptation of content delivery, and quantitative measurement of experiential learning.
Vector theory of gravity: solution of dark energy problem
Svidzinsky, Anatoly A
2015-01-01
We propose an alternative classical theory of gravity which assumes that background geometry of the Universe is fixed four dimensional Euclidean space and gravity is a vector field $A_{k}$ in this space which breaks the Euclidean symmetry. Direction of $A_{k}$ gives the time coordinate, while perpendicular directions are spatial coordinates. Vector gravitational field is coupled to matter universally and minimally through the equivalent metric $f_{ik}$ which is a functional of $A_{k}$. We show that such assumptions yield a unique theory of gravity, it is free of black holes and to the best of our knowledge it passes all available tests. For cosmology our theory predicts the same evolution of the Universe as general relativity with cosmological constant and zero spatial curvature. However, the present theory provides explanation of the dark energy as energy of gravitational field induced by the Universe expansion and yields, with no free parameters, the value of $\\Omega _{\\Lambda }=2/3\\approx 0.67$ which agree...
An investigation into low-lying electronic states of HCS{sub 2} via threshold photoelectron imaging
Qin, Zhengbo; Cong, Ran; Liu, Zhiling; Xie, Hua; Tang, Zichao, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn; Fan, Hongjun, E-mail: zctang@dicp.ac.cn, E-mail: fanhj@dicp.ac.cn [State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023 (China)
2014-06-07
Low-energy photoelectron imaging spectra of HCS{sub 2}{sup ?} are reported for the first time. Vibrationally resolved photodetachment transitions from the ground state of HCS{sub 2}{sup ?} to the ground state and low-lying excited states of HCS{sub 2} are observed. Combined with the ab intio calculations and Franck-Condon simulations, well-resolved vibrational spectra demonstrate definitive evidence for the resolution of the ground-state and excited states of HCS{sub 2} radical in the gaseous phase. The ground state and two low-lying excited states of HCS{sub 2} radical are assigned as {sup 2}B{sub 2}, {sup 2}A{sub 2}, and {sup 2}A{sub 1} states, respectively. The adiabatic electron affinity is determined to be 2.910 ± 0.007 eV. And the term energies of the excited states, T{sub 0} = 0.451 ± 0.009 eV and 0.553 ± 0.009 eV, are directly measured from the experimental data, respectively. Angular filtering photoelectron spectra are carried out to assist in the spectral band assignment.
Mathematics 227 -Vector Analysis. Introduction Instructor: Daniel Offin
Offin, Dan
the magnetic poles of the earth higher than at equator. Measurement? Â· heat flux density (rate of heat flow per://WWW. mast.queensu.ca /~offind/ math227 Examples of flow rates and flux Â· Calgary, June 2013, Bow and Elbow rivers catastrophic flooding in and around Calgary Alberta. On CBC it is announced that flow rate
A unit vector for characterizing the spin polarization of free electron
Chun-Fang Li; Yan Wang
2010-08-05
New degrees of freedom having the form of a unit vector are identified for characterizing the spin polarization of free electron. It is shown that when only the spin is considered, the non-commutativity of the Cartesian components of the Pauli vector allows us to use the azimuthal angle of a second direction, denoted by unit vector $\\mathbf I$, with respect to the quantization direction to characterize the spin polarization. The rotation of $\\mathbf I$ through an angle about the quantization axis leads to a rotation of the spin polarization vector through twice the angle about the same axis. Discussions are also made in Heisenberg picture as well. Upon utilizing this approach to a free electron and letting the quantization direction for each plane wave be the wave vector, we arrive at a representation in which the unit vector $\\mathbf I$ functions as an independent index to characterize the spin polarization.
Ellis, Sebastian A R; Gopalakrishna, Shrihari; Wells, James D
2014-01-01
With the renewed interest in vector-like fermion extensions of the Standard Model, we present here a study of multiple vector-like theories and their phenomenological implications. Our focus is mostly on minimal flavor conserving theories that couple the vector-like fermions to the SM gauge fields and mix only weakly with SM fermions so as to avoid flavor problems. We present calculations for precision electroweak and vector-like state decays, which are needed to investigate compatibility with currently known data. We investigate the impact of vector-like fermions on Higgs boson production and decay, including loop contributions, in a wide variety of vector-like extensions and their parameter spaces.
Barclay, J.A.; Steyert, W.A.
1981-01-27
An apparatus and method for refrigeration are disclosed which provides efficient refrigeration over temperature ranges in excess of 20/sup 0/C and which requires no maintenance and is, therefore, usable on an unmanned satellite. The apparatus comprises a superconducting magnet which may be solenoidal. A piston comprising a substance such as a rare earth substance which is maintained near its Curie temperature reciprocates through the bore of the solenoidal magnet. A magnetic drive rod is connected to the piston and appropriate heat sinks are connected thereto. The piston is driven by a suitable mechanical drive such as an electric motor and cam. In practicing the invention, the body of the piston is magnetized and demagnetized as it moves through the magnetic field of the solenoid to approximate any of the following cycles or a condition thereof as well as, potentially, other cycles: Brayton, Carnot, Ericsson, and Stirling. Advantages of the present invention include: that refrigeration can be accomplished over at least a 20/sup 0/C scale at superconducting temperatures as well as at more conventional temperatures; very high efficiency, high reliability, and small size. (LCL)
Exact Rotating Magnetic Traversable Wormholes satisfying the Energy Conditions
Tonatiuh Matos; Galaxia Miranda
2015-07-09
In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field) with an arbitrary coupling constant, as source of gravitation. We obtain an exact solution of the Einstein equations using this source that represents a magnetized rotating WH. This space-time has a naked ring singularity, probably untouchable as in \\cite{Matos:2012gj}, but otherwise regular. The WH throat lies on the disc bounded by the ring singularity, which keeps the throat open without requiring exotic matter, that means, satisfying all the energy conditions. After analyzing the geodesic motion and the tidal forces we find that a test particle can go through the WH without troubles.
Exact Rotating Magnetic Traversable Wormholes satisfying the Energy Conditions
Matos, Tonatiuh
2015-01-01
In this work we wonder if there is a way to generate a wormhole (WH) in nature using "normal" matter. In order to give a first answer to this question, we study a massless scalar field coupled to an electromagnetic one (dilatonic field) with an arbitrary coupling constant, as source of gravitation. We obtain an exact solution of the Einstein equations using this source that represents a magnetized rotating WH. This space-time has a naked ring singularity, probably untouchable as in \\cite{Matos:2012gj}, but otherwise regular. The WH throat lies on the disc bounded by the ring singularity, which keeps the throat open without requiring exotic matter, that means, satisfying all the energy conditions. After analyzing the geodesic motion and the tidal forces we find that a test particle can go through the WH without troubles.
Thomas Wiegelmann; Bernd Inhester; Bernhard Kliem; Gherardo Valori; Thomas Neukirch
2006-12-21
CONTEXT: As the coronal magnetic field can usually not be measured directly, it has to be extrapolated from photospheric measurements into the corona. AIMS: We test the quality of a non-linear force-free coronal magnetic field extrapolation code with the help of a known analytical solution. METHODS: The non-linear force-free equations are numerically solved with the help of an optimization principle. The method minimizes an integral over the force-free and solenoidal condition. As boundary condition we use either the magnetic field components on all six sides of the computational box in Case I or only on the bottom boundary in Case II. We check the quality of the reconstruction by computing how well force-freeness and divergence-freeness are fulfilled and by comparing the numerical solution with the analytical solution. The comparison is done with magnetic field line plots and several quantitative measures, like the vector correlation, Cauchy Schwarz, normalized vector error, mean vector error and magnetic energy. RESULTS: For Case I the reconstructed magnetic field shows good agreement with the original magnetic field topology, whereas in Case II there are considerable deviations from the exact solution. This is corroborated by the quantitative measures, which are significantly better for Case I. CONCLUSIONS: Despite the strong nonlinearity of the considered force-free equilibrium, the optimization method of extrapolation is able to reconstruct it; however, the quality of reconstruction depends significantly on the consistency of the input data, which is given only if the known solution is provided also at the lateral and top boundaries, and on the presence or absence of flux concentrations near the boundaries of the magnetogram.
The Poincare-Lyapounov-Nekhoroshev theorem for involutory systems of vector fields
Gaeta, Giuseppe [Dipartimento di Matematica, Universita di Milano, via Saldini 50, I-20133 Milan (Italy)]. E-mail: gaeta@mat.unimi.it
2006-06-15
We extend the Poincare-Lyapounov-Nekhoroshev theorem from torus actions and invariant tori to general (non-abelian) involutory systems of vector fields and general invariant manifolds.
Inbar, Moshe
June, 2003 Journal of Vector Ecology 31 Nuisance chironomids in waste water stabilization ponds from waste water stabilization ponds in central Israel created severe nuisance to nearby residents
Magnetic nanoparticle temperature estimation
Weaver, John B.; Rauwerdink, Adam M.; Hansen, Eric W.
2009-05-15
The authors present a method of measuring the temperature of magnetic nanoparticles that can be adapted to provide in vivo temperature maps. Many of the minimally invasive therapies that promise to reduce health care costs and improve patient outcomes heat tissue to very specific temperatures to be effective. Measurements are required because physiological cooling, primarily blood flow, makes the temperature difficult to predict a priori. The ratio of the fifth and third harmonics of the magnetization generated by magnetic nanoparticles in a sinusoidal field is used to generate a calibration curve and to subsequently estimate the temperature. The calibration curve is obtained by varying the amplitude of the sinusoidal field. The temperature can then be estimated from any subsequent measurement of the ratio. The accuracy was 0.3 deg. K between 20 and 50 deg. C using the current apparatus and half-second measurements. The method is independent of nanoparticle concentration and nanoparticle size distribution.
Aized, D.; Schwall, R.E.
1999-06-22
A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.
Wireless Magnetic Sensor Applications in Transportation Infrastructure
Sanchez, Rene Omar
2012-01-01
2.2 Wireless Magnetic Sensors Vehicle Detection2.3 Vehicle Re-Identification Using Wireless MagneticPerformance iv 6 Wireless Magnetic Sensor Applications for
Magnetized static black Saturn
Stoytcho S. Yazadjiev
2008-02-06
We construct a new static solution to the 5D Einstein-Maxwell equations describing a static black hole surrounded by a non-rotating dipole black ring. The configuration is kept in equilibrium by an external magnetic field interacting with the dipole charge of the black ring. The properties of the black Saturn-like configuration are studied and the basic physical quantities are calculated. The solution demonstrates 2-fold continuous non-uniqueness of the 5D magnetized static neutral black objects for fixed total mass and Melvin background.